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Sample records for high-yield d-t neutron

  1. High yield neutron generators using the DD reaction

    Energy Technology Data Exchange (ETDEWEB)

    Vainionpaa, J. H.; Harris, J. L.; Piestrup, M. A.; Gary, C. K.; Williams, D. L.; Apodaca, M. D.; Cremer, J. T. [Adelphi technology, 2003 E. Bayshore Rd. 94061, Redwood City, CA (United States); Ji, Qing; Ludewigt, B. A. [Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Jones, G. [G and J Enterprise, 1258 Quary Ln, Suite F, Pleasanton California 94566 (United States)

    2013-04-19

    A product line of high yield neutron generators has been developed at Adelphi technology inc. The generators use the D-D fusion reaction and are driven by an ion beam supplied by a microwave ion source. Yields of up to 5 Multiplication-Sign 10{sup 9} n/s have been achieved, which are comparable to those obtained using the more efficient D-T reaction. The microwave-driven plasma uses the electron cyclotron resonance (ECR) to produce a high plasma density for high current and high atomic ion species. These generators have an actively pumped vacuum system that allows operation at reduced pressure in the target chamber, increasing the overall system reliability. Since no radioactive tritium is used, the generators can be easily serviced, and components can be easily replaced, providing essentially an unlimited lifetime. Fast neutron source size can be adjusted by selecting the aperture and target geometries according to customer specifications. Pulsed and continuous operation has been demonstrated. Minimum pulse lengths of 50 {mu}s have been achieved. Since the generators are easily serviceable, they offer a long lifetime neutron generator for laboratories and commercial systems requiring continuous operation. Several of the generators have been enclosed in radiation shielding/moderator structures designed for customer specifications. These generators have been proven to be useful for prompt gamma neutron activation analysis (PGNAA), neutron activation analysis (NAA) and fast neutron radiography. Thus these generators make excellent fast, epithermal and thermal neutron sources for laboratories and industrial applications that require neutrons with safe operation, small footprint, low cost and small regulatory burden.

  2. High yield neutron generators using the DD reaction

    Science.gov (United States)

    Vainionpaa, J. H.; Harris, J. L.; Piestrup, M. A.; Gary, C. K.; Williams, D. L.; Apodaca, M. D.; Cremer, J. T.; Ji, Qing; Ludewigt, B. A.; Jones, G.

    2013-04-01

    A product line of high yield neutron generators has been developed at Adelphi technology inc. The generators use the D-D fusion reaction and are driven by an ion beam supplied by a microwave ion source. Yields of up to 5 × 109 n/s have been achieved, which are comparable to those obtained using the more efficient D-T reaction. The microwave-driven plasma uses the electron cyclotron resonance (ECR) to produce a high plasma density for high current and high atomic ion species. These generators have an actively pumped vacuum system that allows operation at reduced pressure in the target chamber, increasing the overall system reliability. Since no radioactive tritium is used, the generators can be easily serviced, and components can be easily replaced, providing essentially an unlimited lifetime. Fast neutron source size can be adjusted by selecting the aperture and target geometries according to customer specifications. Pulsed and continuous operation has been demonstrated. Minimum pulse lengths of 50 μs have been achieved. Since the generators are easily serviceable, they offer a long lifetime neutron generator for laboratories and commercial systems requiring continuous operation. Several of the generators have been enclosed in radiation shielding/moderator structures designed for customer specifications. These generators have been proven to be useful for prompt gamma neutron activation analysis (PGNAA), neutron activation analysis (NAA) and fast neutron radiography. Thus these generators make excellent fast, epithermal and thermal neutron sources for laboratories and industrial applications that require neutrons with safe operation, small footprint, low cost and small regulatory burden.

  3. Utilization of low voltage D-T neutron generators in neutron physics studies

    Energy Technology Data Exchange (ETDEWEB)

    Singkarat, S.

    1995-08-01

    In a small nuclear laboratory of a developing country a low voltage D-T neutron generator can be a very useful scientific apparatus. Such machines have been used successfully for more than 40 years in teaching and scientific research. The original continuous mode 150-kV D-T neutron generator has been modified to have also a capability of producing 2-ns pulsed neutrons. Together with a carefully designed 10 m long flight path collimator and shielding of a 25 cm diameter {center_dot} 10 cm thick BC-501 neutron detector, the pulsing system was successfully used for measuring the double differential cross-section (DDX) of natural iron for 14.1-MeV neutron from the angle of 30 deg to 150 deg in 10 deg steps. In order to extend the utility of the generator, two methods for converting the almost monoenergetic 14-MeV neutrons to monoenergetic neutrons of lower energy were proposed and tested. The first method uses a pulsed neutron generator and the second method uses an ordinary continuous mode generator. The latter method was successfully used to measure the scintillation light output of a 1.4 cm diameter spherical NE-213 scintillation detector. The neutron generator has also been used in the continuous search for improved neutron detection techniques. There is a proposal, based on Monte Carlo calculations, of using a scintillation fiber for a fast neutron spectrometer. Due to the slender shape of the fiber, the pattern of produced light gives a peak in the pulse height spectrum instead of the well-known rectangular-like distribution, when the fiber is bombarded end-on by a beam of 14-MeV neutrons. Experimental investigations were undertaken. Detailed investigations on the light transportation property of a short fiber were performed. The predicted peak has not yet been found but the fiber detector may be developed as a directional discrimination fast neutron detector. 18 refs.

  4. Monte Carlo Simulation for Moderator of Compact D-T Neutron Generator

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In order to study the neutron moderation of D-T neutron generator, moderators with diffident materials and structures are predicted by Monte Carlo simulations. Neutron generator is simplified as the diameter 20 cm, length 25 cm cylinder. The target is very

  5. Feasibility of sealed D-T neutron generator as neutron source for liver BNCT and its beam shaping assembly.

    Science.gov (United States)

    Liu, Zheng; Li, Gang; Liu, Linmao

    2014-04-01

    This paper involves the feasibility of boron neutron capture therapy (BNCT) for liver tumor with four sealed neutron generators as neutron source. Two generators are placed on each side of the liver. The high energy of these emitted neutrons should be reduced by designing a beam shaping assembly (BSA) to make them useable for BNCT. However, the neutron flux decreases as neutrons pass through different materials of BSA. Therefore, it is essential to find ways to increase the neutron flux. In this paper, the feasibility of using low enrichment uranium as a neutron multiplier is investigated to increase the number of neutrons emitted from D-T neutron generators. The neutron spectrum related to our system has a proper epithermal flux, and the fast and thermal neutron fluxes comply with the IAEA recommended values.

  6. High yield neutron generator based on a high-current gasdynamic electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Skalyga, V.; Sidorov, A. [Institute of Applied Physics of Russian Academy of Sciences, 46 Ulyanova St., Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina St., Nizhny Novgorod (Russian Federation); Izotov, I.; Golubev, S.; Razin, S. [Institute of Applied Physics of Russian Academy of Sciences, 46 Ulyanova St., Nizhny Novgorod (Russian Federation); Strelkov, A. [Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Tarvainen, O.; Koivisto, H.; Kalvas, T. [Department of Physics, University of Jyväskylä, Jyväskylä (Finland)

    2015-09-07

    In present paper, an approach for high yield compact D-D neutron generator based on a high current gasdynamic electron cyclotron resonance ion source is suggested. Results on dense pulsed deuteron beam production with current up to 500 mA and current density up to 750 mA/cm{sup 2} are demonstrated. Neutron yield from D{sub 2}O and TiD{sub 2} targets was measured in case of its bombardment by pulsed 300 mA D{sup +} beam with 45 keV energy. Neutron yield density at target surface of 10{sup 9} s{sup −1} cm{sup −2} was detected with a system of two {sup 3}He proportional counters. Estimations based on obtained experimental results show that neutron yield from a high quality TiD{sub 2} target bombarded by D{sup +} beam demonstrated in present work accelerated to 100 keV could reach 6 × 10{sup 10} s{sup −1} cm{sup −2}. It is discussed that compact neutron generator with such characteristics could be perspective for a number of applications like boron neutron capture therapy, security systems based on neutron scanning, and neutronography.

  7. Compact D-D/D-T neutron generators and their applications

    Energy Technology Data Exchange (ETDEWEB)

    Lou, Tak Pui [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    Neutron generators based on the 2H(d,n)3He and 3H(d,n)4He fusion reactions are the most commonly available neutron sources. The applications of current commercial neutron generators are often limited by their low neutron yield and their short operational lifetime. A new generation of D-D/D-T fusion-based neutron generators has been designed at Lawrence Berkeley National Laboratory (LBNL) by using high current ion beams hitting on a self-loading target that has a large surface area to dissipate the heat load. This thesis describes the rationale behind the new designs and their potential applications. A survey of other neutron sources is presented to show their advantages and disadvantages compared to the fusion-based neutron generator. A prototype neutron facility was built at LBNL to test these neutron generators. High current ion beams were extracted from an RF-driven ion source to produce neutrons. With an average deuteron beam current of 24 mA and an energy of 100 keV, a neutron yield of >109 n/s has been obtained with a D-D coaxial neutron source. Several potential applications were investigated by using computer simulations. The computer code used for simulations and the variance reduction techniques employed were discussed. A study was carried out to determine the neutron flux and resolution of a D-T neutron source in thermal neutron scattering applications for condensed matter experiments. An error analysis was performed to validate the scheme used to predict the resolution. With a D-T neutron yield of 1014 n/s, the thermal neutron flux at the sample was predicted to be 7.3 x 105 n/cm2s. It was found that the resolution of cold neutrons was better than that of thermal neutrons when the duty factor is high. This neutron generator could be efficiently used for research and educational purposes at universities. Additional applications studied were positron production and

  8. Compact D-D/D-T neutron generators and their applications

    Energy Technology Data Exchange (ETDEWEB)

    Lou, Tak Pui

    2003-05-01

    Neutron generators based on the {sup 2}H(d,n){sup 3}He and {sup 3}H(d,n){sup 4}He fusion reactions are the most commonly available neutron sources. The applications of current commercial neutron generators are often limited by their low neutron yield and their short operational lifetime. A new generation of D-D/D-T fusion-based neutron generators has been designed at Lawrence Berkeley National Laboratory (LBNL) by using high current ion beams hitting on a self-loading target that has a large surface area to dissipate the heat load. This thesis describes the rationale behind the new designs and their potential applications. A survey of other neutron sources is presented to show their advantages and disadvantages compared to the fusion-based neutron generator. A prototype neutron facility was built at LBNL to test these neutron generators. High current ion beams were extracted from an RF-driven ion source to produce neutrons. With an average deuteron beam current of 24 mA and an energy of 100 keV, a neutron yield of >10{sup 9} n/s has been obtained with a D-D coaxial neutron source. Several potential applications were investigated by using computer simulations. The computer code used for simulations and the variance reduction techniques employed were discussed. A study was carried out to determine the neutron flux and resolution of a D-T neutron source in thermal neutron scattering applications for condensed matter experiments. An error analysis was performed to validate the scheme used to predict the resolution. With a D-T neutron yield of 10{sup 14} n/s, the thermal neutron flux at the sample was predicted to be 7.3 x 10{sup 5} n/cm{sup 2}s. It was found that the resolution of cold neutrons was better than that of thermal neutrons when the duty factor is high. This neutron generator could be efficiently used for research and educational purposes at universities. Additional applications studied were positron production and Boron Neutron Capture Therapy (BNCT). The

  9. Radioactivity measurements of ITER materials using the TFTR D-T neutron field

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A.; Abdou, M.A. [California Univ., Los Angeles, CA (United States). School of Engineering and Applied Science; Barnes, C.W. [Los Alamos National Lab., NM (United States); Kugel, H.W. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Loughlin, M.J. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-08-01

    The availability of high D-T fusion neutron yields at TFTR has provided a useful opportunity to directly measure D-T neutron-induced radioactivity in a realistic tokamak fusion reactor environment for materials of vital interest to ITER. These measurements are valuable for characterizing radioactivity in various ITER candidate materials. for validating complex neutron transport calculations, and for meeting fusion reactor licensing requirements. The radioactivity measurements at TFTR involve potential ITER materials including stainless steel 316, vanadium, titanium, chromium, silicon, iron, cobalt, nickel, molybdenum, aluminum, copper, zinc. zirconium, niobium, and tungsten. Small samples of these materials were irradiated close to the plasma and just outside the vacuum vessel wall of TFTR, locations of different neutron energy spectra. Saturation activities for both threshold and capture reactions were measured. Data from dosimetric reactions have been used to obtain preliminary neutron energy spectra. Spectra from the first wall were compared to calculations from ITER and to measurements from accelerator-based tests.

  10. Monte Carlo simulations of a D-T neutron generator shielding for landmine detection

    Energy Technology Data Exchange (ETDEWEB)

    Reda, A.M., E-mail: amreda2005@yahoo.com [College of Science, Shaqra University, Al-Dawadme, P.O. Box 1040 (Saudi Arabia)

    2011-10-15

    Shielding for a D-T sealed neutron generator has been designed using the MCNP5 Monte Carlo radiation transport code. The neutron generator will be used in field for the detection of explosives, landmines, drugs and other 'threat' materials. The optimization of the detection of buried objects was started by studying the signal-to-noise ratio for different geometric conditions. - Highlights: > A landmine detection system based on neutron fast/slow analysis has been designed. > Shielding for a D-T sealed neutron generator tube has been designed using Monte Carlo radiation transport code. > Detection of buried objects was started by studying the signal-to-noise ratio for different geometric conditions. > The signal-to-background ratio optimized at one position for all depths.

  11. Neutron temporal diagnostic for high-yield deuterium-tritium cryogenic implosions on OMEGA

    Science.gov (United States)

    Stoeckl, C.; Boni, R.; Ehrne, F.; Forrest, C. J.; Glebov, V. Yu.; Katz, J.; Lonobile, D. J.; Magoon, J.; Regan, S. P.; Shoup, M. J.; Sorce, A.; Sorce, C.; Sangster, T. C.; Weiner, D.

    2016-05-01

    A next-generation neutron temporal diagnostic (NTD) capable of recording high-quality data for the highest anticipated yield cryogenic deuterium-tritium (DT) implosion experiments was recently installed at the Omega Laser Facility. A high-quality measurement of the neutron production width is required to determine the hot-spot pressure achieved in inertial confinement fusion experiments—a key metric in assessing the quality of these implosions. The design of this NTD is based on a fast-rise-time plastic scintillator, which converts the neutron kinetic energy to 350- to 450-nm-wavelength light. The light from the scintillator inside the nose-cone assembly is relayed ˜16 m to a streak camera in a well-shielded location. An ˜200× reduction in neutron background was observed during the first high-yield DT cryogenic implosions compared to the current NTD installation on OMEGA. An impulse response of ˜40 ± 10 ps was measured in a dedicated experiment using hard x-rays from a planar target irradiated with a 10-ps short pulse from the OMEGA EP laser. The measured instrument response includes contributions from the scintillator rise time, optical relay, and streak camera.

  12. A novel design of beam shaping assembly to use D-T neutron generator for BNCT.

    Science.gov (United States)

    Kasesaz, Yaser; Karimi, Marjan

    2016-12-01

    In order to use 14.1MeV neutrons produced by d-T neutron generators, two special and novel Beam Shaping Assemblies (BSA), including multi-layer and hexagonal lattice have been suggested and the effect of them has been investigated by MCNP4C Monte Carlo code. The results show that the proposed BSA can provide the qualified epithermal neutron beam for BNCT. The final epithermal neutron flux is about 6e9 n/cm2.s. The final proposed BSA has some different advantages: 1) it consists of usual and well-known materials (Pb, Al, Fluental and Cd); 2) it has a simple geometry; 3) it does not need any additional gamma filter; 4) it can provide high flux of epithermal neutrons. As this type of neutron source is under development in the world, it seems that they can be used clinically in a hospital considering the proposed BSA.

  13. A D-D/D-T fusion reaction based neutron generator system for liver tumor BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Koivunoro, H.; Lou, T.P.; Leung, K. N.; Reijonen, J.

    2003-04-02

    Boron-neutron capture therapy (BNCT) is an experimental radiation treatment modality used for highly malignant tumor treatments. Prior to irradiation with low energetic neutrons, a 10B compound is located selectively in the tumor cells. The effect of the treatment is based on the high LET radiation released in the {sup 10}B(n,{alpha}){sup 7}Li reaction with thermal neutrons. BNCT has been used experimentally for brain tumor and melanoma treatments. Lately applications of other severe tumor type treatments have been introduced. Results have shown that liver tumors can also be treated by BNCT. At Lawrence Berkeley National Laboratory, various compact neutron generators based on D-D or D-T fusion reactions are being developed. The earlier theoretical studies of the D-D or D-T fusion reaction based neutron generators have shown that the optimal moderator and reflector configuration for brain tumor BNCT can be created. In this work, the applicability of 2.5 MeV neutrons for liver tumor BNCT application was studied. The optimal neutron energy for external liver treatments is not known. Neutron beams of different energies (1eV < E < 100 keV) were simulated and the dose distribution in the liver was calculated with the MCNP simulation code. In order to obtain the optimal neutron energy spectrum with the D-D neutrons, various moderator designs were performed using MCNP simulations. In this article the neutron spectrum and the optimized beam shaping assembly for liver tumor treatments is presented.

  14. Development of thin foil Faraday collector as a lost alpha particle diagnostic for high yield D-T tokamak fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Van Belle, P.; Jarvis, O.N.; Sadler, G.J. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Cecil, F.E. [Colorado School of Mines, Golden, CO (United States)

    1994-07-01

    Alpha particle confinement is necessary for ignition of a D-T tokamak fusion plasma and for first wall protection. Due to high radiation backgrounds and temperatures, scintillators and semiconductor detectors may not be used to study alpha particles which are lost to the first wall during the D-T programs on JET and ITER. An alternative method of charged particle spectrometry capable of operation in these harsh environments, is proposed: it consists of thin foils of electrically isolated conductors with the flux of alpha particles determined by the positive current flowing from the foils. 2 refs., 3 figs.

  15. Absolute calibration of TFTR neutron detectors for D-T plasma operation

    Energy Technology Data Exchange (ETDEWEB)

    Jassby, D.L.; Johnson, L.C.; Roquemore, A.L.; Strachan, J.D.; Johnson, D.W.; Medley, S.S.; Young, K.M. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Barnes, C.W. [Los Alamos National Lab., NM (United States)

    1995-03-01

    The two most sensitive TFTR fission-chamber detectors were absolutely calibrated in situ by a D-T neutron generator ({approximately}5 {times} 10{sup 7} n/s) rotated once around the torus in each direction, with data taken at about 45 positions. The combined uncertainty for determining fusion neutron rates, including the uncertainty in the total neutron generator output ({plus_minus}9%), counting statistics, the effect of coil coolant, detector stability, cross-calibration to the current mode or log Campbell mode and to other fission chambers, and plasma position variation, is about {plus_minus}13%. The NE-451 (ZnS) scintillators and {sup 4}He proportional counters that view the plasma in up to 10 collimated sightlines were calibrated by scanning. the neutron generator radially and toroidally in the horizontal midplane across the flight tubes of 7 cm diameter. Spatial integration of the detector responses using the calibrated signal per unit chord-integrated neutron emission gives the global neutron source strength with an overall uncertainty of {plus_minus}14% for the scintillators and {plus_minus}15% for the {sup 4}He counters.

  16. Calorimetric and ionimetric dosimetry intercomparisons II: d + T neutron source at the Antoni Van Leeuwenhoek hospital.

    Science.gov (United States)

    McDonald, J C; Ma, I C; Mijhnheer, B J; Zoetelief, H

    1981-01-01

    A series of dosimetric measurements was carried out at the Antoni van Leeuwenhoek Hospital, Amsterdam, using a Philips d + T generator, which produced neutrons with energies of approximately 14 MeV. A-150 plastic ionization chambers, an A-150 plastic calorimeter, and a GM dosimeter were used to determine total absorbed dose and the photon absorbed dose fraction. The ion chambers were calibrated in a 60Co gamma-ray field in air and compared in a phantom placed in the 60Co gamma-ray beam. Comparison of the total absorbed dose derived from the ionization chamber measurements to that determined using the calorimeter indicated agreement for the neutron measurements between the techniques to within +/- 2%.

  17. Study on the impact of pair production interaction on D-T controllable neutron density logging.

    Science.gov (United States)

    Yu, Huawei; Zhang, Li; Hou, Boran

    2016-05-01

    This paper considers the effect of pair production on the precision of D-T controllable neutron source density logging. Firstly, the principle of the traditional density logging and pulsed neutron density logging are analyzed and then gamma ray cross sections as a function of energy for various minerals are compared. In addition, the advantageous areas of Compton scattering and pair production interactions on high-energy gamma ray pulse height spectrum and the errors of a controllable source density measurement are studied using a Monte Carlo simulation method. The results indicate that density logging mainly utilizes the Compton scattering of gamma rays, while the attenuation of neutron induced gamma rays and the precision of neutron gamma density measurements are affected by pair production interactions, particularly in the gamma rays with energy higher than 2MeV. By selecting 0.2-2MeV energy range and performing proper lithology correction, the effect of pair production can be eliminated effectively and the density measurement error can be rendered close to the precision of chemical source density logging.

  18. Benchmark experiment on vanadium assembly with D-T neutrons. Leakage neutron spectrum measurement

    Energy Technology Data Exchange (ETDEWEB)

    Kokooo; Murata, I.; Nakano, D.; Takahashi, A. [Osaka Univ., Suita (Japan); Maekawa, F.; Ikeda, Y.

    1998-03-01

    The fusion neutronics benchmark experiments have been done for vanadium and vanadium alloy by using the slab assembly and time-of-flight (TOF) method. The leakage neutron spectra were measured from 50 keV to 15 MeV and comparison were done with MCNP-4A calculations which was made by using evaluated nuclear data of JENDL-3.2, JENDL-Fusion File and FENDL/E-1.0. (author)

  19. Measurement of helium production cross sections of iron for d-T neutrons by helium accumulation method

    Energy Technology Data Exchange (ETDEWEB)

    Takao, Yoshiyuki; Kanda, Yukinori; Nagae, Koji; Fujimoto, Toshihiro [Kyushu Univ., Fukuoka (Japan); Ikeda, Yujiro

    1997-03-01

    Helium production cross sections of Iron were measured by helium accumulation method for neutron energies from 13.5 to 14.9 MeV. Iron samples were irradiated with FNS, an intense d-T neutron source of JAERI. As the neutron energy varies according to the emission angle at the neutron source, the samples were set around the neutron source and were irradiated by neutrons of different energy depending on each sample position. The amount of helium produced in a sample was measured by Helium Atoms Measurement System at Kyushu University. The results of this work are in good agreement with other experimental data in the literature and also compared with the evaluated values in JENDL-3. (author)

  20. Monte Carlo simulation of moderator and reflector in coal analyzer based on a D-T neutron generator.

    Science.gov (United States)

    Shan, Qing; Chu, Shengnan; Jia, Wenbao

    2015-11-01

    Coal is one of the most popular fuels in the world. The use of coal not only produces carbon dioxide, but also contributes to the environmental pollution by heavy metals. In prompt gamma-ray neutron activation analysis (PGNAA)-based coal analyzer, the characteristic gamma rays of C and O are mainly induced by fast neutrons, whereas thermal neutrons can be used to induce the characteristic gamma rays of H, Si, and heavy metals. Therefore, appropriate thermal and fast neutrons are beneficial in improving the measurement accuracy of heavy metals, and ensure that the measurement accuracy of main elements meets the requirements of the industry. Once the required yield of the deuterium-tritium (d-T) neutron generator is determined, appropriate thermal and fast neutrons can be obtained by optimizing the neutron source term. In this article, the Monte Carlo N-Particle (MCNP) Transport Code and Evaluated Nuclear Data File (ENDF) database are used to optimize the neutron source term in PGNAA-based coal analyzer, including the material and shape of the moderator and neutron reflector. The optimized targets include two points: (1) the ratio of the thermal to fast neutron is 1:1 and (2) the total neutron flux from the optimized neutron source in the sample increases at least 100% when compared with the initial one. The simulation results show that, the total neutron flux in the sample increases 102%, 102%, 85%, 72%, and 62% with Pb, Bi, Nb, W, and Be reflectors, respectively. Maximum optimization of the targets is achieved when the moderator is a 3-cm-thick lead layer coupled with a 3-cm-thick high-density polyethylene (HDPE) layer, and the neutron reflector is a 27-cm-thick hemispherical lead layer.

  1. Investigation of Workplace-like Calibration Fields via a Deuterium-Tritium (D-T) Neutron Generator.

    Science.gov (United States)

    Mozhayev, Andrey V; Piper, Roman K; Rathbone, Bruce A; McDonald, Joseph C

    2017-04-01

    Radiation survey meters and personal dosimeters are typically calibrated in reference neutron fields based on conventional radionuclide sources, such as americium-beryllium (Am-Be) or californium-252 (Cf), either unmodified or heavy-water moderated. However, these calibration neutron fields differ significantly from the workplace fields in which most of these survey meters and dosimeters are being used. Although some detectors are designed to yield an approximately dose-equivalent response over a particular neutron energy range, the response of other detectors is highly dependent upon neutron energy. This, in turn, can result in significant over- or underestimation of the intensity of neutron radiation and/or personal dose equivalent determined in the work environment. The use of simulated workplace neutron calibration fields that more closely match those present at the workplace could improve the accuracy of worker, and workplace, neutron dose assessment. This work provides an overview of the neutron fields found around nuclear power reactors and interim spent fuel storage installations based on available data. The feasibility of producing workplace-like calibration fields in an existing calibration facility has been investigated via Monte Carlo simulations. Several moderating assembly configurations, paired with a neutron generator using the deuterium tritium (D-T) fusion reaction, were explored.

  2. High-fidelity MCNP modeling of a D-T neutron generator for active interrogation of special nuclear material

    Science.gov (United States)

    Katalenich, Jeff; Flaska, Marek; Pozzi, Sara A.; Hartman, Michael R.

    2011-10-01

    Fast and robust methods for interrogation of special nuclear material (SNM) are of interest to many agencies and institutions in the United States. It is well known that passive interrogation methods are typically sufficient for plutonium identification because of a relatively high neutron production rate from 240Pu [1]. On the other hand, identification of shielded uranium requires active methods using neutron or photon sources [2]. Deuterium-deuterium (2.45 MeV) and deuterium-tritium (14.1 MeV) neutron-generator sources have been previously tested and proven to be relatively reliable instruments for active interrogation of nuclear materials [3,4]. In addition, the newest generators of this type are small enough for applications requiring portable interrogation systems. Active interrogation techniques using high-energy neutrons are being investigated as a method to detect hidden SNM in shielded containers [4,5]. Due to the thickness of some containers, penetrating radiation such as high-energy neutrons can provide a potential means of probing shielded SNM. In an effort to develop the capability to assess the signal seen from various forms of shielded nuclear materials, the University of Michigan Neutron Science Laboratory's D-T neutron generator and its shielding were accurately modeled in MCNP. The generator, while operating at nominal power, produces approximately 1×10 10 neutrons/s, a source intensity which requires a large amount of shielding to minimize the dose rates around the generator. For this reason, the existing shielding completely encompasses the generator and does not include beam ports. Therefore, several MCNP simulations were performed to estimate the yield of uncollided 14.1-MeV neutrons from the generator for active interrogation experiments. Beam port diameters of 5, 10, 15, 20, and 25 cm were modeled to assess the resulting neutron fluxes. The neutron flux outside the beam ports was estimated to be approximately 2×10 4 n/cm 2 s.

  3. Development of high-intensity D-D and D-T neutron sources and neutron filters for medical and industrial applications

    Energy Technology Data Exchange (ETDEWEB)

    Verbeke, Jerome Maurice [Univ. of California, Berkeley, CA (United States)

    2000-05-10

    This thesis consists of three main parts. The first one relates to boron neutron capture therapy. It summarizes the guidelines obtained by numerical simulations for the treatment of shallow and deep-seated brain tumors, as well as the results on the design of beam-shaping assemblies to moderate D-D and D-T neutrons to epithermal energies. The second part is about boron neutron capture synovectomy for the treatment of rheumatoid arthritis. Optimal neutron energy for treatment and beam-shaping assembly designs are summarized in this section. The last part is on the development of the sealed neutron generator, including experimental results on the prototype ion source and the prototype accelerator column.

  4. Benchmark experiment on vanadium assembly with D-T neutrons. In-situ measurement

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Fujio; Kasugai, Yoshimi; Konno, Chikara; Wada, Masayuki; Oyama, Yukio; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Murata, Isao; Kokooo; Takahashi, Akito

    1998-03-01

    Fusion neutronics benchmark experimental data on vanadium were obtained for neutrons in almost entire energies as well as secondary gamma-rays. Benchmark calculations for the experiment were performed to investigate validity of recent nuclear data files, i.e., JENDL Fusion File, FENDL/E-1.0 and EFF-3. (author)

  5. Pyroelectric crystal D-D and D-T neutron generators

    Science.gov (United States)

    Danon, Y.

    2012-04-01

    Pyroelectric neutron generators are a recent development utilizing the pyroelectric effect to produce an accelerating electric field and thus enabling creation of small electron and ion accelerators without external high voltage power supply. The principle of operation includes a pyroelectric crystal (LiTaO3 for example) placed in vacuum and simple heating (or cooling) of the crystal to cause a change in polarization. The change in polarization creates free charges on the faces of the clyndrical z-cut crystal and due to its small capacitance this creates a high potential between one crystal face to the other which is placed at ground potential. To produce neutrons the crystal is placed in low pressure deuterium gas and when the crystal is heated or cooled it ionizes the gas and accelerates deuterium ions towards a deuterated or tritated target. A configuration with two crystals can double the acceleration potential and thus increase neutron production. When operating such a device x-rays with energy over 200 keV about 105 neutrons per heating cycle can be produced. Research is focused on improving the neutron yield, the emission reproducibility, and shortening the heating cycle. Neutron generators based on this technology can be made small portable and relatively cheap compared to sealed tube technology. Further development is needed in order to increase the neutron yield closer to the theoretical limit for a specific crystals size.

  6. MCNPX simulations of the silicon carbide semiconductor detector response to fast neutrons from D-T nuclear reaction

    Science.gov (United States)

    Sedlačková, Katarína; Šagátová, Andrea; Zat'ko, Bohumír; Nečas, Vladimír; Solar, Michael; Granja, Carlos

    2016-09-01

    Silicon Carbide (SiC) has been long recognized as a suitable semiconductor material for use in nuclear radiation detectors of high-energy charged particles, gamma rays, X-rays and neutrons. The nuclear interactions occurring in the semiconductor are complex and can be quantified using a Monte Carlo-based computer code. In this work, the MCNPX (Monte Carlo N-Particle eXtended) code was employed to support detector design and analysis. MCNPX is widely used to simulate interaction of radiation with matter and supports the transport of 34 particle types including heavy ions in broad energy ranges. The code also supports complex 3D geometries and both nuclear data tables and physics models. In our model, monoenergetic neutrons from D-T nuclear reaction were assumed as a source of fast neutrons. Their energy varied between 16 and 18.2 MeV, according to the accelerating voltage of the deuterons participating in D-T reaction. First, the simulations were used to calculate the optimum thickness of the reactive film composed of High Density PolyEthylene (HDPE), which converts neutral particles to charged particles and thusly enhancing detection efficiency. The dependency of the optimal thickness of the HDPE layer on the energy of the incident neutrons has been shown for the inspected energy range. Further, from the energy deposited by secondary charged particles and recoiled ions, the detector response was modeled and the effect of the conversion layer on detector response was demonstrated. The results from the simulations were compared with experimental data obtained for a detector covered by a 600 and 1300 μm thick conversion layer. Some limitations of the simulations using MCNPX code are also discussed.

  7. Study of d-t neutron energy spectra at JET using natural diamond detectors

    CERN Document Server

    Krasilnikov, A V; Belle, P V; Jarvis, O N; Sadler, G J

    2002-01-01

    Four natural diamond detectors (NDDs) have been used for deuterium-tritium neutron spectrometry and flux monitoring during the 1997 tritium experiments (DTE1) carried out in the Joint European Torus (JET). Neutron energy spectra have been measured with three NDDs for discharge scenarios that included (a) hot ion H-mode studies using combined neutral-beam (NB) and ion cyclotron resonance frequency (ICRF) heating, (b) optimized shear experiments using combined NB and ICRF heating, (c) alpha-particles heating experiments with NB heating only and (d) ICRF heating studies without NB heating. Within the statistical accuracy of the data, the spectra can be adequately represented by Gaussian distributions, whose fwhm values provide effective ion temperatures that characterize the energy distributions of the ions taking part in fusion reactions.

  8. Tokamak D T fusion neutron source requirements for closing the nuclear fuel cycle

    Science.gov (United States)

    Stacey, W. M.

    2007-03-01

    This paper summarizes a series of conceptual design studies conducted with the purpose of determining if tokamak fusion neutron sources based on ITER physics and technology could meet the neutron source requirements for sub-critical fast-spectrum nuclear reactors that would help to close the nuclear fuel cycle by transmuting the transuranics in spent nuclear fuel. The studies were constrained to nuclear reactor and materials technologies under consideration in the US nuclear programme. Fuel cycle studies indicate that fusion neutron sources in the range ~200-500 MW would meet the needs of transmutation reactors, depending on other constraints such as materials damage to the nuclear fuel. A tokamak with R = 3.75 m, a = 1.1 m, B = 5.7-5.9 T, q95 = 3.00-4.0, I = 8.3-10 MA, βN = 2.0-2.85, HIPB98 = 1.0-1.06, γcd = 0.6 A Wm-2 would meet these requirements.

  9. Method for measuring prompt gamma-rays generated by D-T neutrons bombarding a depleted uranium spherical shell

    CERN Document Server

    Qin, Jianguo; Jiang, Li; Liu, Rong; Zhang, Xinwei; Ye, Bangjiao; Zhu, Tonghua

    2015-01-01

    The prompt gamma-ray spectrum from depleted uranium (DU) spherical shells induced by 14 MeV D-T neutrons is measured. Monte Carlo (MC) simulation gives the largest prompt gamma flux with the optimal thickness of the DU spherical shells 3-5 cm and the optimal frequency of neutron pulse 1 MHz. The method of time of flight and pulse shape coincidence with energy (DC-TOF) is proposed, and the subtraction of the background gamma-rays discussed in detail. The electron recoil spectrum and time spectrum of the prompt gamma-rays are obtained based on a 2"*2" BC501A liquid scintillator detector. The energy spectrum and time spectrum of prompt gamma-rays are obtained based on an iterative unfolding method that can remove the influence of {\\gamma}-rays response matrix and pulsed neutron shape. The measured time spectrum and the calculated results are roughly consistent with each other. Experimental prompt gamma-ray spectrum in the 0.4-3 MeV energy region agree well with MC simulation based on the ENDF/BVI.5 library, and ...

  10. Detection of fast neutrons from D-T nuclear reaction using a 4H-SiC radiation detector

    Science.gov (United States)

    Zatko, Bohumir; Sagatova, Andrea; Sedlackova, Katarina; Necas, Vladimir; Dubecky, Frantisek; Solar, Michael; Granja, Carlos

    2016-09-01

    The particle detector based on a high purity epitaxial layer of 4H-SiC exhibits promising properties in detection of various types of ionizing radiation. Due to the wide band gap of 4H-SiC semiconductor material, the detector can reliably operate at room and also elevated temperatures. In this work we focused on detection of fast neutrons generated the by D-T (deuterium-tritium) nuclear reaction. The epitaxial layer with a thickness of 105 μm was used as a detection part. A circular Schottky contact of a Au/Ni double layer was evaporated on both sides of the detector material. The detector structure was characterized by current-voltage and capacitance-voltage measurements, at first. The results show very low current density (SiC detector is caused by the elastic and inelastic scattering on the silicon or carbide component of the detector material. Another possibility that increases the detection efficiency is the use of a conversion layer. In our measurements, we glued a HDPE (high density polyethylene) conversion layer on the detector Schottky contact to transform fast neutrons to protons. Hydrogen atoms contained in the conversion layer have a high probability of interaction with neutrons through elastic scattering. Secondary generated protons flying to the detector can be easily detected. The detection properties of detectors with and without the HDPE conversion layer were compared.

  11. Method for measuring prompt γ-rays generated by D-T neutrons bombarding a depleted uranium spherical shell

    Science.gov (United States)

    Qin, Jian-Guo; Lai, Cai-Feng; Jiang, Li; Liu, Rong Zhang, Xin-Wei; Ye, Bang-Jiao; Zhu, Tong-Hua

    2016-01-01

    The prompt γ-ray spectrum from depleted uranium (DU) spherical shells induced by 14 MeV D-T neutrons is measured. Monte Carlo (MC) simulation gives the largest prompt γ flux with the optimal thickness of the DU spherical shells 3-5 cm and the optimal frequency of neutron pulse 1 MHz. The method of time of flight and pulse shape coincidence with energy (DC-TOF) is proposed, and the subtraction of the background γ-rays discussed in detail. The electron recoil spectrum and time spectrum of the prompt γ-rays are obtained based on a 2″×2″ BC501A liquid scintillator detector. The energy spectrum and time spectrum of prompt γ-rays are obtained based on an iterative unfolding method that can remove the influence of γ-rays response matrix and pulsed neutron shape. The measured time spectrum and the calculated results are roughly consistent with each other. Experimental prompt γ-ray spectrum in the 0.4-3 MeV energy region agrees well with MC simulation based on the ENDF/BVI.5 library, and the discrepancies for the integral quantities of γ-rays of energy 0.4-1 MeV and 1-3 MeV are 9.2% and 1.1%, respectively. Supported by National Special Magnetic Confinement Fusion Energy Research, China (2015GB108001) and National Natural Science Foundation of China (91226104)

  12. Development and characterization of a high yield transportable pulsed neutron source with efficient and compact pulsed power system

    Science.gov (United States)

    Verma, Rishi; Mishra, Ekansh; Dhang, Prosenjit; Sagar, Karuna; Meena, Manraj; Shyam, Anurag

    2016-09-01

    The results of characterization experiments carried out on a newly developed dense plasma focus device based intense pulsed neutron source with efficient and compact pulsed power system are reported. Its high current sealed pseudospark switch based low inductance capacitor bank with maximum stored energy of ˜10 kJ is segregated into four modules of ˜2.5 kJ each and it cumulatively delivers peak current in the range of 400 kA-600 kA (corresponding to charging voltage range of 14 kV-18 kV) in a quarter time period of ˜2 μs. The neutron yield performance of this device has been optimized by discretely varying deuterium filling gas pressure in the range of 6 mbar-11 mbar at ˜17 kV/550 kA discharge. At ˜7 kJ/8.5 mbar operation, the average neutron yield has been measured to be in the order of ˜4 × 109 neutrons/pulse which is the highest ever reported neutron yield from a plasma focus device with the same stored energy. The average forward to radial anisotropy in neutron yield is found to be ˜2. The entire system is contained on a moveable trolley having dimensions 1.5 m × 1 m × 0.7 m and its operation and control (up to the distance of 25 m) are facilitated through optically isolated handheld remote console. The overall compactness of this system provides minimum proximity to small as well as large samples for irradiation. The major intended application objective of this high neutron yield dense plasma focus device development is to explore the feasibility of active neutron interrogation experiments by utilization of intense pulsed neutron sources.

  13. Design and optimization of a beam shaping assembly for BNCT based on D-T neutron generator and dose evaluation using a simulated head phantom.

    Science.gov (United States)

    Rasouli, Fatemeh S; Masoudi, S Farhad

    2012-12-01

    A feasibility study was conducted to design a beam shaping assembly for BNCT based on D-T neutron generator. The optimization of this configuration has been realized in different steps. This proposed system consists of metallic uranium as neutron multiplier, TiF(3) and Al(2)O(3) as moderators, Pb as reflector, Ni as shield and Li-Poly as collimator to guide neutrons toward the patient position. The in-air parameters recommended by IAEA were assessed for this proposed configuration without using any filters which enables us to have a high epithermal neutron flux at the beam port. Also a simulated Snyder head phantom was used to evaluate dose profiles due to the irradiation of designed beam. The dose evaluation results and depth-dose curves show that the neutron beam designed in this work is effective for deep-seated brain tumor treatments even with D-T neutron generator with a neutron yield of 2.4×10(12) n/s. The Monte Carlo Code MCNP-4C is used in order to perform these calculations.

  14. Georgia Tech Studies of Sub-Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel

    Science.gov (United States)

    Stacey, W. M.

    2009-09-01

    The possibility that a tokamak D-T fusion neutron source, based on ITER physics and technology, could be used to drive sub-critical, fast-spectrum nuclear reactors fueled with the transuranics (TRU) in spent nuclear fuel discharged from conventional nuclear reactors has been investigated at Georgia Tech in a series of studies which are summarized in this paper. It is found that sub-critical operation of such fast transmutation reactors is advantageous in allowing longer fuel residence time, hence greater TRU burnup between fuel reprocessing stages, and in allowing higher TRU loading without compromising safety, relative to what could be achieved in a similar critical transmutation reactor. The required plasma and fusion technology operating parameter range of the fusion neutron source is generally within the anticipated operational range of ITER. The implications of these results for fusion development policy, if they hold up under more extensive and detailed analysis, is that a D-T fusion tokamak neutron source for a sub-critical transmutation reactor, built on the basis of the ITER operating experience, could possibly be a logical next step after ITER on the path to fusion electrical power reactors. At the same time, such an application would allow fusion to contribute to meeting the nation's energy needs at an earlier stage by helping to close the fission reactor nuclear fuel cycle.

  15. Design of a high-current low-energy beam transport line for an intense D-T/D-D neutron generator

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xiaolong, E-mail: luxl@lzu.edu.cn [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Wang, Junrun [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Zhang, Yu; Li, Jianyi; Xia, Li; Zhang, Jie; Ding, Yanyan; Jiang, Bing; Huang, Zhiwu; Ma, Zhanwen; Wei, Zheng [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Qian, Xiangping; Xu, Dapeng; Lan, Changlin [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Yao, Zeen, E-mail: zeyao@lzu.edu.cn [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

    2016-03-01

    An intense D-T/D-D neutron generator is currently being developed at the Lanzhou University. The Cockcroft–Walton accelerator, as a part of the neutron generator, will be used to accelerate and transport the high-current low-energy beam from the duoplasmatron ion source to the rotating target. The design of a high-current low-energy beam transport (LEBT) line and the dynamics simulations of the mixed beam were carried out using the TRACK code. The results illustrate that the designed beam line facilitates smooth transportation of a deuteron beam of 40 mA, and the number of undesired ions can be reduced effectively using two apertures.

  16. Irradiation facility for boron neutron capture therapy application based on a rf-driven D-T neutron source and a new beam shaping assembly (abstract)

    Science.gov (United States)

    Cerullo, N.; Esposito, J.; Leung, K. N.

    2002-02-01

    Selecting the best neutron source for boron neutron capture therapy (BNCT) requires optimizing neutron beam parameters. This involves solving many complex problems. Safety issues related to the use of nuclear reactor in hospital environments, as well as lower costs have led to interest in the development of accelerator-driven neutron sources. The BNCT research programs at the Nuclear Departments of Pisa and Genova Universities (DIMNP and DITEC) focus on studies of new concepts for accelerator-based DT neutron sources. Simple and compact accelerator designs using relatively low deuteron beam energy, ˜100 keV, have been developed which, in turn, can generate high neutron yields. New studies have been started for optimization of moderator materials for the 14.1 MeV DT neutrons. Our aim is to obtain an epithermal neutron beam for therapeutic application at the exit end, with minimal beam intensity losses, the specific goal is to achieve an epithermal neutron flux of at least of 1×109 n/cm2 s at the beam port, with low gamma and fast neutron dose contamination. According to the most recent neutron BNCT beam parameters some moderating and spectrum shifter materials and geometrical configurations have thus far been tested, and neutron and gamma beam data at beam port have been computed. A possible beam shaping assembly model has been designed. This research demonstrates that a DT neutron source could be successfully implemented for BNCT application, with performance surpassing the minimum requirements stated above, using DT neutron sources with yields in the range 1013-1014 n/s. The latest Monte Carlo simulation results of an accelerator based facility which relies on a rf-driven DT fusion neutron generator will be presented.

  17. Analysis of Induced Gamma Activation by D-T Neutrons in Selected Fusion Reactor Relevant Materials with EAF-2010

    Science.gov (United States)

    Klix, Axel; Fischer, Ulrich; Gehre, Daniel

    2016-02-01

    Samples of lanthanum, erbium and titanium which are constituents of structural materials, insulating coatings and tritium breeder for blankets of fusion reactor designs have been irradiated in a fusion peak neutron field. The induced gamma activities were measured and the results were used to check calculations with the European activation system EASY-2010. Good agreement for the prediction of major contributors to the contact dose rate of the materials was found, but for minor contributors the calculation deviated up to 50%.

  18. Use of D-T-produced fast neutrons for in vivo body composition analysis: a reference method for nutritional assessment in the elderly

    Energy Technology Data Exchange (ETDEWEB)

    Kehayias, J.J. [USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington St., Boston, 02111-1524 MA (United States)

    2004-05-01

    Body composition has become the main outcome of many nutritional intervention studies including osteoporosis, malnutrition, obesity, AIDS, and aging. Traditional indirect body composition methods developed with healthy young adults do not apply to the elderly or diseased. Fast neutron activation (for N and P) and neutron inelastic scattering (for C and O) are used to assess in vivo elements characteristic of specific body compartments. Non-bone phosphorus for muscle is measured by the {sup 31}P(n,{alpha}){sup 28}Al reaction, and nitrogen for protein via the {sup 14}N(n,2n){sup 13}N fast neutron reaction. Inelastic neutron scattering is used to measure total body carbon and oxygen. Body fat is derived from carbon after correcting for contributions from protein, bone, and glycogen. Carbon-to-oxygen ratio (C/O) is used to measure the distribution of fat and lean tissue in the body and to monitor small changes of lean mass. A sealed, D-T neutron generator is used for the production of fast neutrons. Carbon and oxygen mass and their ratio are measured in vivo at a radiation exposure of less than 0.06 mSv. Gamma-ray spectra are collected using large BGO detectors and analyzed for the 4.43 MeV state of carbon and 6.13 MeV state of oxygen, simultaneously with the irradiation. P and N analysis by delayed fast neutron activation is performed by transferring the patient to a shielded room equipped with an array of NaI(Tl) detectors. A combination of measurements makes possible the assessment of the ''quality'' of fat-free mass. The neutron generator system is used to evaluate the efficacy of new treatments, to study mechanisms of lean tissue depletion with aging, and to investigate methods for preserving function and quality of life in the elderly. It is also used as a reference method for the validation of portable instruments of nutritional assessment. (orig.)

  19. Analysis of Induced Gamma Activation by D-T Neutrons in Selected Fusion Reactor Relevant Materials with EAF-2010

    Directory of Open Access Journals (Sweden)

    Klix Axel

    2016-01-01

    Full Text Available Samples of lanthanum, erbium and titanium which are constituents of structural materials, insulating coatings and tritium breeder for blankets of fusion reactor designs have been irradiated in a fusion peak neutron field. The induced gamma activities were measured and the results were used to check calculations with the European activation system EASY-2010. Good agreement for the prediction of major contributors to the contact dose rate of the materials was found, but for minor contributors the calculation deviated up to 50%.

  20. Monte Carlo simulation of prompt gamma-ray spectra from depleted uranium under D-T neutron irradiation and electron recoil spectra in a liquid scintillator detector

    CERN Document Server

    Qin, Jianguo; Liu, Rong; Zhu, Tonghua; Zhang, Xinwei; Ye, Bangjiao

    2015-01-01

    To overcome the problem of inefficient computing time and unreliable results in MCNP5 calculation, a two-step method is adopted to calculate the energy deposition of prompt gamma-rays in detectors for depleted uranium spherical shells under D-T neutrons irradiation. In the first step, the gamma-ray spectrum for energy below 7 MeV is calculated by MCNP5 code; secondly, the electron recoil spectrum in a BC501A liquid scintillator detector is simulated based on EGSnrc Monte Carlo Code with the gamma-ray spectrum from the first step as input. The comparison of calculated results with experimental ones shows that the simulations agree well with experiment in the energy region 0.4-3 MeV for the prompt gamma-ray spectrum and below 4 MeVee for the electron recoil spectrum. The reliability of the two-step method in this work is validated.

  1. A derivation of bulk-motion insensitive implosion metrics inferred from neutron and high-energy x-ray emission in a series of high yield implosions on the NIF

    Science.gov (United States)

    Springer, P. T.; Macphee, A. G.; Hurricane, O. A.; Callahan, D. A.; Casey, D. T.; Cerjan, C. J.; Dewald, E. L.; Dittrich, T. R.; Doeppner, T.; Edgell, D. H.; Edwards, M. J.; Gaffney, J.; Grim, G. P.; Haan, S.; Hammer, J. H.; Hinkel, D. E.; Berzak Hopkins, L. F.; Jones, O.; Kritcher, A. L.; Le Pape, S.; Ma, T.; Milovich, J.; Munro, D. H.; Pak, A.; Park, H. S.

    2015-11-01

    A suite of nuclear and x-ray data is used to deduce key implosion performance metrics at stagnation including the hotspot pressure, energy, and the role of alpha heating on producing the observed yield. Key to this analysis is a determination of the burn-averaged temperature of the hot plasma so that the nuclear reactivity and yield can then be used to deduce the plasma density and pressure. In this presentation we examine the systematics of both neutron and high-energy x-ray emission (22 keV x-ray monochromator) from a series of high yield implosions on the NIF. The advantage of incorporating high energy x-rays into the analysis is their insignificant attenuation and insensitivity to bulk flows, thus providing insight as to whether these effects complicate the interpretation of the nuclear data, and that a precipitous drop in their production is expected as the thermal temperature is reduced. A dynamic model for hotspot assembly is developed that incorporates thermal conduction, radiative losses, and alpha heating, which simultaneously matches both neutron and x-ray data with nearly identical nuclear and x-ray derived thermal temperatures. Work performed under the auspices of the USDoE by Lawrence Livermore National Laboratory under contract DE-AC52-07NA273.

  2. High-dynamic-range neutron time-of-flight detector used to infer the D(t,n){sup 4}He and D(d,n){sup 3}He reaction yield and ion temperature on OMEGA

    Energy Technology Data Exchange (ETDEWEB)

    Forrest, C. J., E-mail: cforrest@lle.rochester.edu; Glebov, V. Yu.; Goncharov, V. N.; Knauer, J. P.; Radha, P. B.; Regan, S. P.; Romanofsky, M. H.; Sangster, T. C.; Shoup, M. J.; Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299 (United States)

    2016-11-15

    Upgraded microchannel-plate–based photomultiplier tubes (MCP-PMT’s) with increased stability to signal-shape linearity have been implemented on the 13.4-m neutron time-of-flight (nTOF) detector at the Omega Laser Facility. This diagnostic uses oxygenated xylene doped with diphenyloxazole C{sub 15}H{sub 11}NO + p-bis-(o-methylstyryl)-benzene (PPO + bis-MSB) wavelength shifting dyes and is coupled through four viewing ports to fast-gating MCP-PMT’s, each with a different gain to allow one to measure the light output over a dynamic range of 1 × 10{sup 6}. With these enhancements, the 13.4-m nTOF can measure the D(t,n){sup 4}He and D(d,n){sup 3}He reaction yields and average ion temperatures in a single line of sight. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the neutron yield from 1 × 10{sup 9} to 1 × 10{sup 14} and the ion temperature with an accuracy approaching 5% for both the D(t,n){sup 4}He and D(d,n){sup 3}He reactions.

  3. High-dynamic-range neutron time-of-flight detector used to infer the D(t,n)(4)He and D(d,n)(3)He reaction yield and ion temperature on OMEGA.

    Science.gov (United States)

    Forrest, C J; Glebov, V Yu; Goncharov, V N; Knauer, J P; Radha, P B; Regan, S P; Romanofsky, M H; Sangster, T C; Shoup, M J; Stoeckl, C

    2016-11-01

    Upgraded microchannel-plate-based photomultiplier tubes (MCP-PMT's) with increased stability to signal-shape linearity have been implemented on the 13.4-m neutron time-of-flight (nTOF) detector at the Omega Laser Facility. This diagnostic uses oxygenated xylene doped with diphenyloxazole C15H11NO + p-bis-(o-methylstyryl)-benzene (PPO + bis-MSB) wavelength shifting dyes and is coupled through four viewing ports to fast-gating MCP-PMT's, each with a different gain to allow one to measure the light output over a dynamic range of 1 × 10(6). With these enhancements, the 13.4-m nTOF can measure the D(t,n)(4)He and D(d,n)(3)He reaction yields and average ion temperatures in a single line of sight. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the neutron yield from 1 × 10(9) to 1 × 10(14) and the ion temperature with an accuracy approaching 5% for both the D(t,n)(4)He and D(d,n)(3)He reactions.

  4. High-dynamic-range neutron time-of-flight detector used to infer the D(t,n)4He and D(d,n)3He reaction yield and ion temperature on OMEGA

    Science.gov (United States)

    Forrest, C. J.; Glebov, V. Yu.; Goncharov, V. N.; Knauer, J. P.; Radha, P. B.; Regan, S. P.; Romanofsky, M. H.; Sangster, T. C.; Shoup, M. J.; Stoeckl, C.

    2016-11-01

    Upgraded microchannel-plate-based photomultiplier tubes (MCP-PMT's) with increased stability to signal-shape linearity have been implemented on the 13.4-m neutron time-of-flight (nTOF) detector at the Omega Laser Facility. This diagnostic uses oxygenated xylene doped with diphenyloxazole C15H11NO + p-bis-(o-methylstyryl)-benzene (PPO + bis-MSB) wavelength shifting dyes and is coupled through four viewing ports to fast-gating MCP-PMT's, each with a different gain to allow one to measure the light output over a dynamic range of 1 × 106. With these enhancements, the 13.4-m nTOF can measure the D(t,n)4He and D(d,n)3He reaction yields and average ion temperatures in a single line of sight. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the neutron yield from 1 × 109 to 1 × 1014 and the ion temperature with an accuracy approaching 5% for both the D(t,n)4He and D(d,n)3He reactions.

  5. Measurement of tritium production rate distribution in natural LiAlO{sub 2}/HDPE assembly irradiated by D-T neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Jakhar, Shrichand, E-mail: shrichand.s@gmail.com [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Abhangi, Mitul; Rao, C.V.S.; Basu, T.K. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Bhade, Sonali P.D.; Reddy, Priyanka J. [Radiation Safety Systems Division, Bhabha Atomic Research Center, Trombay, Mumbai (India)

    2012-02-15

    A neutronics experiment was performed to measure the tritium production rate (TPR) profile in the breeder assembly with LiAlO{sub 2} as breeder and high density polyethylene (HDPE) as neutron reflector. The breeder assembly was irradiated with 14 MeV neutrons from DT neutron generator at IPR Neutronics Laboratory. The objective of the experiment was to validate the tritium production prediction capability of the Monte-Carlo code MCNP and FENDL 2.1 data library. The tritium production rate profile in the breeding assembly was measured by irradiating Li{sub 2}CO{sub 3} pellets kept at various locations and then tritium counting liquid scintillation technique. Experiment was analyzed with 3D Monte-Carlo code MCNP with FENDL 2.1 cross-section data library. The calculation results were found to agree with the measured tritium production rates except one point near to the source. This experiment is a starting experiment in the series of benchmark experiments for the Indian Demo breeding blanket.

  6. Monte Carlo simulation on n-γ density logging using D-T neutron generator%D-T中子源n-γ密度测井规律的蒙特卡罗模拟

    Institute of Scientific and Technical Information of China (English)

    何雄英; 郑世平; 卢小龙; 姚泽恩

    2013-01-01

    根据D-T反应中子的能谱和角分布数据,建立了中子源模型;根据石灰岩地层标准刻度井群数据,建立了井模型.采用MCNP程序模拟了井中中子和γ射线的输运,得到了不同地层密度、不同源距处NaI探测器中的混合γ能谱和非弹γ能谱.在混合γ能谱2.5~4.5 MeV能区开窗,混合γ射线相对计数随源距的变化曲线显示,源距应选择在20~80 cm,密度与混合γ射线计数之间呈现非线性关系.在非弹γ能谱1.0~8.0 MeV能区开窗,非弹γ射线相对计数随源距的变化数据显示,源距应选择在20~40 cm或80 cm附近,密度与非弹γ射线计数之间成近似线性关系.%D-T neutron source model is developed according to the neutron spectrum and the neutron angular distribution of D-T reaction. A standard calibration well model is built. The transports of D-T neutron and γ-ray in the well are simulated using MCNP code. Mixed γ-spectrum and inelastic γ-spectrum in the Nal detector are obtained for different distance and different density. The data of the mixed gamma count in the energy range of 2. 5 to 4. 5 MeV as a function of distance show that the detector should be located in the space of 20-80 cm. The nonlinear relationships between the density and the mixed gamma count are presented. The data of the inelastic gamma count in the energy range of 1. 0 to 8. 0 MeV as a function of distance show that the detector should be located in the space of 20-40 cm or in the neighborhood of 80 cm. The relationships between the density and the inelastic gamma count can be approximatively expressed as a linear function.

  7. Experimental study of the secondary neutron angular spectra emitted from polyethylene slabs with D-T neutron source%D-T中子与平板型聚乙烯材料作用的次级中子角度谱实验研究

    Institute of Scientific and Technical Information of China (English)

    言杰; 刘荣; 蒋励; 鹿心鑫; 朱通华; 林菊芳; 王玫; 温中伟; 汪一夫

    2011-01-01

    基于反冲质子法建立了一种测量D-T中子与平板型宏观样品作用的次级中子角度谱的实验方法.为保证探测器的能量线性并在较低的中子有效测量下阈(0.5MeV)情况下获得好的中子-伽马射线甄别性能,采用高、低能段分别测量的方法.采用事件记录法,同时记录了次级中子和伴随伽马射线的脉冲形状甄别和脉冲幅度二维信息,利用基于ROOT数据分析平台编写的离线数据分析程序,完成了伴随伽马射线的挑选和扣除,以及高、低两能段反冲质子谱的拼接,并成功的将神经网络技术应用于中子能谱的解谱,获得了D-T中子与9和18cm厚平板型聚乙烯材料作用的0.5—15MeV的次级中子角度谱实验结果.实验模型的MC模拟由MCNP5完成,数据库采用ENDF-VI,实验结果和MC计算结果在实验不确定度范围内一致.%An experimental method of measuring the secondary neutron angular spectrum from polyethylene slab assembly with D-T neutron source based on the proton-recoil method is developed.In order to ensure the energy linearity of the detector and obtain a good neutron-gamma discrimination capability in the case of a low effective neutron threshold(0.5MeV),neutron energy spectrum is measured in two parts:one is in a high energy region and the other in a lower energy region.The pulse shape discrimination(PSD) and the pulse height distribution(PH) two-dimensional information of the secondary neutron and the associated gamma rays are recorded event-by-event simultaneously.The selection and the deduction of the gamma ray events and the joining of the two-segment energy spectra are carried out by using the off-line data analysis programs written in the ROOT data analysis framework.Furthermore,an artificial neural network technique is used to accomplish the unfolding of the neutron spectra successfully.The experimental results of the second neutron angular spectra from 9cm and 18cm thick

  8. TFTR D-T results

    Energy Technology Data Exchange (ETDEWEB)

    Meade, D.M.

    1995-03-01

    Temperatures, densities and confinement of deuterium plasmas confined in tokamaks have been achieved within the last decade that are approaching those required for a D-T reactor. As a result, the unique phenomena present in a D-T reactor plasma can now be studied in the laboratory. Recent experiments on the Tokamak Fusion Test Reactor (TFTR) have been the first magnetic fusion experiments to study plasmas with reactor fuel concentrations of tritium. The injection of {approximately} 20 MW of tritium and 14 MW of deuterium neutral beams into the TFTR produced a plasma with a T/D density ratio of {approximately} 1 and yielded a maximum fusion power of {approximately} 9.2 MW. The fusion power density in the core of the plasma was {approximately} 1.8 MW m{sup {minus}3} approximating that expected in a D-T fusion reactor. A TFTR plasma with T/D density ratio of {approximately} 1 was found to have {approximately} 20% higher energy confinement time than a comparable D plasma, indicating a confinement scaling with average ion mass, A, of {tau}{sub E} {approximately} A{sup 0.6}. The core ion temperature increased from 30 keV to 37 keV due to a 35% improvement of ion thermal conductivity. Using the electron thermal conductivity from a comparable deuterium plasma, about 50% of the electron temperature increase from 9 keV to 10.6 keV can be attributed to electron heating by the alpha particles. The {approx} 5% loss of alpha particles was consistent with classical first orbit loss without anomalous effects. Initial measurements have been made of the confined energetic alphas and the resultant alpha ash density.

  9. PREOVULATORY FOLLICLE DEVELOPMENT IN HIGH YIELDING COWS

    Directory of Open Access Journals (Sweden)

    Radovan Tomášek

    2013-06-01

    Full Text Available The aim of the study was to examine the development of preovulatory follicles in pregnant and non-pregnant high yielding cows. The treatment by supergestran and oestrophan was used to synchronize the estrous cycle. Ovaries were monitored by transrectal ultrasonography. The linear increase of preovulatory follicles was observed in pregnant (P < 0,001 and non-pregnant (P < 0,001 cows during 8 days before ovulation. In conclusion, preovulatory follicles in pregnant and non-pregnant high yielding cows developed similarly.

  10. Methods for high yield production of terpenes

    Science.gov (United States)

    Kutchan, Toni; Higashi, Yasuhiro; Feng, Xiaohong

    2017-01-03

    Provided are enhanced high yield production systems for producing terpenes in plants via the expression of fusion proteins comprising various combinations of geranyl diphosphate synthase large and small subunits and limonene synthases. Also provided are engineered oilseed plants that accumulate monoterpene and sesquiterpene hydrocarbons in their seeds, as well as methods for producing such plants, providing a system for rapidly engineering oilseed crop production platforms for terpene-based biofuels.

  11. Methods for high yield production of terpenes

    Energy Technology Data Exchange (ETDEWEB)

    Kutchan, Toni; Higashi, Yasuhiro; Feng, Xiaohong

    2017-01-03

    Provided are enhanced high yield production systems for producing terpenes in plants via the expression of fusion proteins comprising various combinations of geranyl diphosphate synthase large and small subunits and limonene synthases. Also provided are engineered oilseed plants that accumulate monoterpene and sesquiterpene hydrocarbons in their seeds, as well as methods for producing such plants, providing a system for rapidly engineering oilseed crop production platforms for terpene-based biofuels.

  12. 一维贫铀/聚乙烯交替系统中D-T中子诱发的232Th(n,γ)反应率的测定与分析%Determination of 232Th(n, γ) reaction rate induced by D-T neutrons in one-dimensional alternate depleted uranium/p olyethylene shells

    Institute of Scientific and Technical Information of China (English)

    羊奕伟; 刘荣; 蒋励; 鹿心鑫; 王玫; 严小松

    2014-01-01

    A series of neutron integral fundamental researches of thorium nuclear data in set-ups containing thorium samples is carried out. One-dimensional alternate depleted uranium/polyethylene shells containing thorium samples are constructed by referring to the conceptual design of fusion-fission hybrid reactor, where a D-T neutron source driven by accelerator is used to simulate the fusion core of the reactor. 232Th (n,γ) reaction rates in samples located at different positions in the shells are measured in 5% uncertainty by using activated thorium sample decay γ-ray off-line measurement technique. The results show that the moderation of polyethylene to 14.1 MeV neutron will efficiently increase the capture rate of thorium, and the depleted uranium is also conducible to this increase obviously. The comparison between our measured data and the results available from mainstream nuclear data bank shows that the calculation results from ENDF/B-VI.6 and JENDL-3.3 are around 6% higher than the experimental results, while the newer ENDF/B-VII.0 will achieve better results, around 4% higher than the experimental results. We recommend the ENDF/B-VII.0 to be used in one-dimensional alternate depleted uranium/polyethylene shells related conceptual design when calculating the 232Th (n,γ) reaction rate.%开展了钍样品装置内钍核参数的积分中子学基础研究.参考混合堆概念设计搭建了内部放置了钍样品的一维贫铀/聚乙烯交替系统装置,采用加速器D-T中子源模拟聚变堆芯,利用前期开发的离线伽马测量方法测定了不同位置、不同中子谱情况下的232Th (n,γ)反应率,不确定度约为5%.结果显示,聚乙烯对14.1 MeV中子的慢化作用可有效提升钍俘获率,且贫铀对钍俘获率也有显著提升作用.实验结果与主流核数据库计算结果的对比显示, ENDF/B-VI.6和JENDL-3.3数据库的计算值比实验值平均约大6%,而较新的ENDF/B-VII.0数据库的计

  13. RGB-D-T based Face Recognition

    DEFF Research Database (Denmark)

    Nikisins, Olegs; Nasrollahi, Kamal; Greitans, Modris

    2014-01-01

    Facial images are of critical importance in many real-world applications from gaming to surveillance. The current literature on facial image analysis, from face detection to face and facial expression recognition, are mainly performed in either RGB, Depth (D), or both of these modalities. But......, such analyzes have rarely included Thermal (T) modality. This paper paves the way for performing such facial analyzes using synchronized RGB-D-T facial images by introducing a database of 51 persons including facial images of different rotations, illuminations, and expressions. Furthermore, a face recognition...

  14. Nutritive Equilibrium in Rice Plant Populations for High Yield

    Institute of Scientific and Technical Information of China (English)

    WANGBOLUN; LIUXINAN; 等

    1999-01-01

    The effects of nitrogen,phosphorus and potassium application level,seed rate and transplanting density on the growth and development of rice plants were studied to find out nutrient status in high-yielding rice plants and to increase grain yield by adequate fertilization.There was an equilibrium relationship among nutrient elements for high-yielding rice plant populations.The equilibrium index of nutrient amount ,content and distribution in high-yielding rice plants should be generally greater than-2 but less than 2.The optimum nutritive proportion of nitrogen:phosphorus:potassium assimilated by the plants was about 10:2:9 at the ripening stage.But the content and the proportion varied with the growth stages,Therefore,the nutrient in rice plant populations should be in a dynamic equilibrium.So as to achieve high yield.

  15. High yield, single droplet electrode arrays for nanoscale printed electronics.

    Science.gov (United States)

    Caironi, Mario; Gili, Enrico; Sakanoue, Tomo; Cheng, Xiaoyang; Sirringhaus, Henning

    2010-03-23

    In this work we demonstrate two building blocks of a scalable manufacturing technology for nanoscale electronic devices based on direct-write printing: an architecture for high-yield printing of electrode gaps with 100 nm dimension and a low-temperature silver complex ink for integration of organic materials with high conductivity metal interconnects. We use single printed droplets that are made to dewet slowly from each other to allow reliable, high yield patterning even in the presence of certain surface defects.

  16. Design of a high DC voltage generator and D-T fuser based on particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Wagner L.; Campos, Tarcisio P.R., E-mail: wagnerleite@ufmg.b, E-mail: campos@nuclear.ufmg.b [Universidade Federal de Minas Gerais (DEN/ UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear

    2011-07-01

    This paper approaches a design and simulation of a high voltage Cockcroft Walton multiplier and a compact size deuteron accelerator addressed in neutron generation by d-t fusion. We proposed a circuit arrangement, which was led to simulations. The particle accelerator was computer-generated providing particle transport and electric potential analysis. As results, the simulated voltage multiplier achieved 119 kV, and the accelerator presented a deuteron beam current up to 15 mA, achieving energies in order to 100 keV. In conclusion, the simulation motivates experimental essays in order to investigate the viability of a deuteron accelerator powered by a Cockcroft-Walton source. Such d-t fusor shall produce an interesting ion beam profile, reaching energy values near the d-t fusion cross section peak. (author)

  17. High-Yield Lithium-Injection Fusion-Energy (HYLIFE) reactor

    Energy Technology Data Exchange (ETDEWEB)

    Blink, J.A.; Hogam, W.J.; Hovingh, J.; Meier, E.R.; Pitts, J.H. (comps.)

    1985-12-23

    The High-Yield Lithium-Injection Fusion Energy (HYLIFE) concept to convent inertial confinement fusion energy into electric power has undergone intensive research and refinement at LLNL since 1978. This paper reports on the final HYLIFE design, focusing on five major areas: the HYLIFE reaction chamber (which includes neutronics, liquid-metal jet-array hydrocynamics, and structural design), supporting systems, primary steam system and balance of plant, safety and environmental protection, and costs. An annotated bibliography of reports applicable to HYLIFE is also provided. We conclude that HYLIFE is a particularly viable concept for the safe, clean production of electrical energy. The liquid-metal jet array, HYLIFE's key design feature, protects the surrounding structural components from x-rays, fusion fuel-pellet debris, neutron damage and activation, and high temperatures and stresses, allowing the structure to last for the plant's entire 30-year lifetime without being replaced. 127 refs., 18 figs.

  18. BRS Pampeira: new irrigated rice cultivar with high yield potential

    Directory of Open Access Journals (Sweden)

    Ariano Martins de Magalhães Júnior

    2016-12-01

    Full Text Available BRS Pampeira is a rice cultivar developed by Embrapa, recommended for irrigated cultivation in Brazil. It shows modern architecture, with high tillering and tolerance to lodging. It stands out for its high yield potential, medium cycle and good grain quality.

  19. Neutron scatter camera

    Science.gov (United States)

    Mascarenhas, Nicholas; Marleau, Peter; Brennan, James S.; Krenz, Kevin D.

    2010-06-22

    An instrument that will directly image the fast fission neutrons from a special nuclear material source has been described. This instrument can improve the signal to background compared to non imaging neutron detection techniques by a factor given by ratio of the angular resolution window to 4.pi.. In addition to being a neutron imager, this instrument will also be an excellent neutron spectrometer, and will be able to differentiate between different types of neutron sources (e.g. fission, alpha-n, cosmic ray, and D-D or D-T fusion). Moreover, the instrument is able to pinpoint the source location.

  20. An evaluation on the design of beam shaping assembly based on the D-T reaction for BNCT

    Science.gov (United States)

    Asnal, M.; Liamsuwan, T.; Onjun, T.

    2015-05-01

    Boron Neutron Capture Therapy (BNCT) can be achieved by using a compact neutron generator such as a compact D-T neutron source, in which neutron energy must be in the epithermal energy range with sufficient flux. For these requirements, a Beam Shaping Assembly (BSA) is needed. In this paper, three BSA designs based on the D-T reaction for BNCT are discussed. It is found that the BSA configuration designed by Rasouli et al. satisfies all of the International Atomic Energy Agency (IAEA) criteria. It consists of 14 cm uranium as multiplier, 23 cm TiF3 and 36 cm Fluental as moderator, 4 cm Fe as fast neutron filter, 1 mm Li as thermal neutron filter, 2.6 cm Bi as gamma ray filter, and Pb as collimator and reflector. It is also found that use of specific filters is important for removing the fast and thermal neutrons and gamma contamination. Moreover, an appropriate neutron source plays a key role in providing a proper epithermal flux.

  1. Stereotypical behaviour at high yielding dairy cows farms - "tongue rolling"

    OpenAIRE

    Prodanović Radiša; Kirovski Danijela; Vujanac Ivan; Nešić Ksenija; Janevski Aleksandar; Marić Jovan; Kukrić Vladimir

    2013-01-01

    The objective of this work was to determine if there was a connection between stereotypical behaviour of high yielding dairy cows breeds and values of biochemical blood parameters. The investigation was carried out in august at loose-housing type of farms, in 30 heads of cattle from four groups: drying (15 to 7 days before calving), puerperium (up to 40 days after calving, early lactation (up to 120 days after calving) and late lactation (200 to 300 days af...

  2. Implementation of the {alpha}-CHERS diagnostic for D-T operation of TFTR

    Energy Technology Data Exchange (ETDEWEB)

    McKee, G.R.; Fonck, R.J. [Wisconsin Univ., Madison, WI (United States). Dept. of Energy; Stratton, F.K. [Princeton Univ., NJ (United States). Plasma Physics Lab.

    1995-03-01

    The {alpha}-CHERS diagnostic is a high throughput charge exchange recombination spectroscopy diagnostic designed to measure the density profile and time evolution of 0-500 keV alpha particles during D-T operation of TFTR. Following successful tests with a prototype ({alpha}-CHERS system, an improved, multi-channel system has been installed for D-T Operation. Three spatial channels may be observed simultaneously, and the spectral resolution of 0.5 nm permits increased alpha energy resolution and improved impurity line identification. More efficient coupling optics between the spectrometer and CCD detectors have increased the light throughput, and radiation shielding has been installed around the detectors and spectrometers to eliminate the neutron/gamma ray noise observed in high power D-D plasmas.

  3. Executive Summary High-Yield Scenario Workshop Series Report

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Park Ovard; Thomas H. Ulrich; David J. Muth Jr.; J. Richard Hess; Steven Thomas; Bryce Stokes

    2009-12-01

    To get a collective sense of the impact of research and development (R&D) on biomass resource availability, and to determine the feasibility that yields higher than baseline assumptions used for past assessments could be achieved to support U.S. energy independence, an alternate “High-Yield Scenario” (HYS) concept was presented to industry experts at a series of workshops held in December 2009. The workshops explored future production of corn/agricultural crop residues, herbaceous energy crops (HECs), and woody energy crops (WECs). This executive summary reports the findings of that workshop.

  4. A high-yield saponification of galactosylceramide I(3)-sulfate.

    Science.gov (United States)

    Koshy, K M; Boggs, J M

    1982-12-01

    A method for the deacylation of galactosylceramide I(3)-sulphate using aqueous methanolic KOH is described. The combination of a relatively low concentration of the alkali (0.3 M) and a moderate reaction temperature (reflux point of 90% methanol) results in the formation of galactosylsphingosine I(3)-sulphate in consistently high yields (61%) with a minimum of side reactions. The product was purified by column chromatography and its identity established by thin layer chromatography, infrared spectroscopy, determination of galactose content and organic sulphate assay using established methods or their modifications.

  5. Development of high-yield influenza A virus vaccine viruses

    Science.gov (United States)

    Ping, Jihui; Lopes, Tiago J.S.; Nidom, Chairul A.; Ghedin, Elodie; Macken, Catherine A.; Fitch, Adam; Imai, Masaki; Maher, Eileen A.; Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Vaccination is one of the most cost-effective ways to prevent infection. Influenza vaccines propagated in cultured cells are approved for use in humans, but their yields are often suboptimal. Here, we screened A/Puerto Rico/8/34 (PR8) virus mutant libraries to develop vaccine backbones (defined here as the six viral RNA segments not encoding haemagglutinin and neuraminidase) that support high yield in cell culture. We also tested mutations in the coding and regulatory regions of the virus, and chimeric haemagglutinin and neuraminidase genes. A combination of high-yield mutations from these screens led to a PR8 backbone that improved the titres of H1N1, H3N2, H5N1 and H7N9 vaccine viruses in African green monkey kidney and Madin–Darby canine kidney cells. This PR8 backbone also improves titres in embryonated chicken eggs, a common propagation system for influenza viruses. This PR8 vaccine backbone thus represents an advance in seasonal and pandemic influenza vaccine development. PMID:26334134

  6. [Study on High-yield Cultivation Measures for Arctii Fructus].

    Science.gov (United States)

    Liu, Shi-yong; Jiang, Xiao-bo; Wang, Tao; Sun, Ji-ye; Hu, Shang-qin; Zhang, Li

    2015-02-01

    To find out the high yield cultivation measures for Arctii Fructus. Completely randomized block experiment design method was used in the field planting, to analyze the effect of different cultivation way on agronomic characters, phenological phase,quality and quantity of Arctii Fructus. Arctium lappa planted on August 28 had the best results of plant height, thousand seeds weight and yield. The highest yield of Arctii Fructus was got at the density of 1,482 plants/667 m2. Arctiin content was in an increase trend with the planting time delay and planting density increasing. The plant height, thousand seeds weight, yield and arctiin content by split application of fertilizer were significantly higher than that by one-time fertilization. Compared with open field Arctium lappa, plant height, yield, arctiin content and relative water content of plastic film mulching Arctium lappa was higher by 7.74%, 10.87%, 6.38% and 24.20%, respectively. In the topping Arctium lappa, the yield was increased by 11.09%, with 39. 89% less branching number. Early planting time and topping shortened the growth cycle of Arctium lappa plant. The high-yield cultivation measures of Arctii Fructus are: around August 28 to sowing, planting density of 1 482 plants/667 m2, split application of fertilizer for four times, covering film on surface of the soil and topping in bolting.

  7. Development of high-yield influenza B virus vaccine viruses.

    Science.gov (United States)

    Ping, Jihui; Lopes, Tiago J S; Neumann, Gabriele; Kawaoka, Yoshihiro

    2016-12-20

    The burden of human infections with influenza A and B viruses is substantial, and the impact of influenza B virus infections can exceed that of influenza A virus infections in some seasons. Over the past few decades, viruses of two influenza B virus lineages (Victoria and Yamagata) have circulated in humans, and both lineages are now represented in influenza vaccines, as recommended by the World Health Organization. Influenza B virus vaccines for humans have been available for more than half a century, yet no systematic efforts have been undertaken to develop high-yield candidates. Therefore, we screened virus libraries possessing random mutations in the six "internal" influenza B viral RNA segments [i.e., those not encoding the major viral antigens, hemagglutinin (HA) and neuraminidase NA)] for mutants that confer efficient replication. Candidate viruses that supported high yield in cell culture were tested with the HA and NA genes of eight different viruses of the Victoria and Yamagata lineages. We identified combinations of mutations that increased the titers of candidate vaccine viruses in mammalian cells used for human influenza vaccine virus propagation and in embryonated chicken eggs, the most common propagation system for influenza viruses. These influenza B virus vaccine backbones can be used for improved vaccine virus production.

  8. Registration of 3D+t coronary CTA and monoplane 2D+t X-ray angiography.

    Science.gov (United States)

    Metz, Coert T; Schaap, Michiel; Klein, Stefan; Baka, Nora; Neefjes, Lisan A; Schultz, Carl J; Niessen, Wiro J; van Walsum, Theo

    2013-05-01

    A method for registering preoperative 3D+t coronary CTA with intraoperative monoplane 2D+t X-ray angiography images is proposed to improve image guidance during minimally invasive coronary interventions. The method uses a patient-specific dynamic coronary model, which is derived from the CTA scan by centerline extraction and motion estimation. The dynamic coronary model is registered with the 2D+t X-ray sequence, considering multiple X-ray time points concurrently, while taking breathing induced motion into account. Evaluation was performed on 26 datasets of 17 patients by comparing projected model centerlines with manually annotated centerlines in the X-ray images. The proposed 3D+t/2D+t registration method performed better than a 3D/2D registration method with respect to the accuracy and especially the robustness of the registration. Registration with a median error of 1.47 mm was achieved.

  9. Combining high biodiversity with high yields in tropical agroforests

    Science.gov (United States)

    Clough, Yann; Barkmann, Jan; Juhrbandt, Jana; Kessler, Michael; Wanger, Thomas Cherico; Anshary, Alam; Buchori, Damayanti; Cicuzza, Daniele; Darras, Kevin; Putra, Dadang Dwi; Erasmi, Stefan; Pitopang, Ramadhanil; Schmidt, Carsten; Schulze, Christian H.; Seidel, Dominik; Steffan-Dewenter, Ingolf; Stenchly, Kathrin; Vidal, Stefan; Weist, Maria; Wielgoss, Arno Christian; Tscharntke, Teja

    2011-01-01

    Local and landscape-scale agricultural intensification is a major driver of global biodiversity loss. Controversially discussed solutions include wildlife-friendly farming or combining high-intensity farming with land-sparing for nature. Here, we integrate biodiversity and crop productivity data for smallholder cacao in Indonesia to exemplify for tropical agroforests that there is little relationship between yield and biodiversity under current management, opening substantial opportunities for wildlife-friendly management. Species richness of trees, fungi, invertebrates, and vertebrates did not decrease with yield. Moderate shade, adequate labor, and input level can be combined with a complex habitat structure to provide high biodiversity as well as high yields. Although livelihood impacts are held up as a major obstacle for wildlife-friendly farming in the tropics, our results suggest that in some situations, agroforests can be designed to optimize both biodiversity and crop production benefits without adding pressure to convert natural habitat to farmland. PMID:21536873

  10. High Yield Preparation Method of Thermally Stable Cellulose Nanofibers

    Directory of Open Access Journals (Sweden)

    Hongli Zhu

    2014-02-01

    Full Text Available The preparation of nanocellulose fibers (NFs is achieved through pretreating cellulose in a NaOH/urea/thiourea solution, and then defibrillating the fibers through ultrasonication, resulting in a high yield of 85.4%. Extensive work has been done to optimize the preparation parameters. The obtained NFs are about 30 nm in diameter with cellulose II crystal structure. They possess high thermal stability with an onset of thermal degradation at 270 °C and a maximum degradation temperature of 370 °C. Such NFs have potential applications in transistors and batteries with high thermal stability. NFs-H were obtained by homogenizing undefibrillated fibers separated from the preparation of NFs. NFs-H were also in cellulose II crystal form but with lower thermal stability due to low crystallinity. They can be applied to make highly transparent paper.

  11. Integrated process for high conversion and high yield protein PEGylation.

    Science.gov (United States)

    Pfister, David; Morbidelli, Massimo

    2016-08-01

    Over the past decades, PEGylation has become a powerful technique to increase the in vivo circulation half-life of therapeutic proteins while maintaining their activity. The development of new therapeutic proteins is likely to require further improvement of the PEGylation methods to reach even better selectivity and yield for reduced costs. The intensification of the PEGylation process was investigated through the integration of a chromatographic step in order to increase yield and conversion for the production of mono-PEGylated protein. Lysozyme was used as a model protein to demonstrate the feasibility of such approach. In the integrated reaction/separation process, chromatography was used as fractionation technique in order to isolate and recycle the unreacted protein from the PEGylated products. This allows operating the reactor with short reaction times so as to minimize the production of multi-PEGylated proteins (i.e., conjugated to more than one polymer). That is, the reaction is stopped before the desired product (i.e., the mono-PEGylated protein) can further react, thus leading to limited conversion but high yield. The recycling of the unreacted protein was then considered to drive the protein overall conversion to completion. This approach has great potential to improve processes whose yield is limited by the further reaction of the product leading to undesirable by-products. Biotechnol. Bioeng. 2016;113: 1711-1718. © 2016 Wiley Periodicals, Inc.

  12. Fast neutron activation analysis by means of low voltage neutron generator

    Science.gov (United States)

    Medhat, M. E.

    A description of D-T neutron generator (NG) is presented. This machine can be used for fast neutron activation analysis applied to determine some selected elements, especially light elements, in different materials. Procedure of neutron flux determination and efficiency calculation is described. Examples of testing some Egyptian natural cosmetics are given.

  13. Nutritional status of high yielding crossbred cow around parturition

    Directory of Open Access Journals (Sweden)

    Mohammad Yousuf

    2016-03-01

    Materials and methods: Nutritional status of cows around the peri-parturient period was investigated for six months in dairy farm. Seven to eight months' pregnant cows were selected for this study. Blood samples from 24 randomly selected cows were collected at stage-1, -2 and -3. The serum was stored at -20C until analyzing glucose, total protein (TP, albumin (Alb, triglycerides (Tg, cholesterol, high density lipoprotein (HDL, low density lipoprotein (LDL, calcium (Ca, magnesium (Mg and phosphorus (P. Results: An increasing trend of glucose level was evidenced (P=0.07 during stage-1. Instead, higher levels of TP were found during stage-3 as compared to the stage-1 and -2. The Alb levels differed significantly (P<0.01 among different stages. A significantly increased (P<0.01 cholesterol, Tg, and HDL were found after parturition (stage-2 and -3 than before parturition (stage-1. LDL was significantly (P=0.02 increased during stage-2 and -3. A significantly higher level of Ca (P<0.01, Mg (P<0.01 and P (P=0.03 were present during stage-1. Glucose, TP, cholesterol and Tg were significantly higher (P<0.01 in cows two months after parturition, while Alb was found to be the highest (P<0.01 in cows immediately after parturition. An increasing trend of LDL (P=0.07 and HDL (P=0.07 were found in the cows two months after parturition. However, Ca levels were significantly (P=0.04 higher in cows two months after parturition. Conclusion: The results indicate that there is alteration of biochemical levels among the study population at three different stages, and these data may be helpful in using the necessary nutrients to the the high yielding cows around their parturition. [J Adv Vet Anim Res 2016; 3(1.000: 68-74

  14. Coherent fluctuations in the initial TFTR D-T experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, E.; Chang, Z.Y.; Budny, R.V.

    1995-03-01

    The initial operation of TFTR with approximately equal power in the tritium and deuterium neutral beam injectors has resulted in the production of fusion power in excess of 9MW and central {beta}{sub {alpha}} > 0.25%. This {beta}{sub {alpha}} is within a factor of 2--3 of the {beta}{sub {alpha}} in projections of ITER performance. Effects of this {alpha} population on TAE modes, sawteeth and fishbone activity are being searched for. The D-T plasmas are also being studied for evidence of changes in MHD activity which might be attributed to the fast {alpha} population. This paper reports on the activity in the Alfven range of frequencies in the D-T plasmas and on detailed measurements of the MHD activity preceding major disruptions in D-D and D-T.

  15. Stereotypical behaviour at high yielding dairy cows farms - "tongue rolling"

    Directory of Open Access Journals (Sweden)

    Prodanović Radiša

    2013-01-01

    Full Text Available The objective of this work was to determine if there was a connection between stereotypical behaviour of high yielding dairy cows breeds and values of biochemical blood parameters. The investigation was carried out in august at loose-housing type of farms, in 30 heads of cattle from four groups: drying (15 to 7 days before calving, puerperium (up to 40 days after calving, early lactation (up to 120 days after calving and late lactation (200 to 300 days after calving. Assessment of stereotypical behaviour (tongue rolling was carried out by the method of careful observation of all the tested animals 2 to 4 hours after morning feeding. Blood samples were taken by puncture of jugular vein from 8 cows out of each animal group. In these blood samples there was determined the concentration of glucose, beta hydroxy-butyric acid (BHBA, total protein (TP, albumin, urea, total bilirubin (TBI, Ca, P, and Mg as well as AST and ALT activities. During the period up to 40 days after calving (puerperium, behavioral disorder in the form of „tongue rolling“ was found out in 4 out of 30 observed animals (13.33%. Average concentrations of all the tested blood parameters during the drying period as well as in early and late lactation were within physiological values for cattle. During puerperium there were found significantly lower values of glycaemia, proteinemia, albuminemia, uremia and magnesiemia in regard to antepartal values (p<0.05, where the values of glycaemia and magnesiemia were below the physiological limit. A the same time, in this group of cows the values of TBI and AST activities were higher than physiological values. Frequent appearance of „tongue rolling“ phenomenon only among cows in the group with deviation of biochemical parameters values, points out to a possible connection between the stereotypical behaviour and biochemical composition of blood. It seems that hypomagnesiemia could be a significant etiopathogenetic factor causing the

  16. THERMAL NEUTRON BACKSCATTER IMAGING.

    Energy Technology Data Exchange (ETDEWEB)

    VANIER,P.; FORMAN,L.; HUNTER,S.; HARRIS,E.; SMITH,G.

    2004-10-16

    Objects of various shapes, with some appreciable hydrogen content, were exposed to fast neutrons from a pulsed D-T generator, resulting in a partially-moderated spectrum of backscattered neutrons. The thermal component of the backscatter was used to form images of the objects by means of a coded aperture thermal neutron imaging system. Timing signals from the neutron generator were used to gate the detection system so as to record only events consistent with thermal neutrons traveling the distance between the target and the detector. It was shown that this time-of-flight method provided a significant improvement in image contrast compared to counting all events detected by the position-sensitive {sup 3}He proportional chamber used in the imager. The technique may have application in the detection and shape-determination of land mines, particularly non-metallic types.

  17. Improved RGB-D-T based Face Recognition

    DEFF Research Database (Denmark)

    Oliu Simon, Marc; Corneanu, Ciprian; Nasrollahi, Kamal

    2016-01-01

    Reliable facial recognition systems are of crucial importance in various applications from entertainment to security. Thanks to the deep-learning concepts introduced in the field, a significant improvement in the performance of the unimodal facial recognition systems has been observed in the recent...... years. At the same time a multimodal facial recognition is a promising approach. This paper combines the latest successes in both directions by applying deep learning Convolutional Neural Networks (CNN) to the multimodal RGB-D-T based facial recognition problem outperforming previously published results....... Furthermore, a late fusion of the CNN-based recognition block with various hand-crafted features (LBP, HOG, HAAR, HOGOM) is introduced, demonstrating even better recognition performance on a benchmark RGB-D-T database. The obtained results in this paper show that the classical engineered features and CNN...

  18. Development of pulsed neutron uranium logging instrument

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin-guang, E-mail: wangxg@upc.edu.cn [School of Geosciences, China University of Petroleum, Qingdao 266580 (China); Engineering Research Center of Nuclear Technology Application (East China Institute of Technology), Ministry of Education, Nanchang 330013 (China); Liu, Dan [China Institute of Atomic Energy, Beijing 102413 (China); Zhang, Feng [School of Geosciences, China University of Petroleum, Qingdao 266580 (China)

    2015-03-15

    This article introduces a development of pulsed neutron uranium logging instrument. By analyzing the temporal distribution of epithermal neutrons generated from the thermal fission of {sup 235}U, we propose a new method with a uranium-bearing index to calculate the uranium content in the formation. An instrument employing a D-T neutron generator and two epithermal neutron detectors has been developed. The logging response is studied using Monte Carlo simulation and experiments in calibration wells. The simulation and experimental results show that the uranium-bearing index is linearly correlated with the uranium content, and the porosity and thermal neutron lifetime of the formation can be acquired simultaneously.

  19. The Prospects for High-Yield ICF with a Z-Pinch Driven Dynamic Hohlraum

    Energy Technology Data Exchange (ETDEWEB)

    CHANDLER, GORDON A.; CHRIEN, R.; COOPER, GARY WAYNE; DERZON, MARK S.; DOUGLAS, MELISSA R.; HEBRON, DAVID E.; LASH, JOEL S.; LEEPER, RAMON J.; MATZEN, M. KEITH; MEHLHORN, THOMAS A.; NASH, THOMAS J.; OLSON, RICHARD E.; PETERSON, D.L.; RUIZ, CARLOS L.; SANFORD, THOMAS W. L.; SLUTZ, STEPHEN A.

    1999-09-07

    Recent success with the Sandia Z machine has renewed interest in utilizing fast z-pinenes for ICF. One promising concept places the ICF capsule internal to the imploding z-pinch. At machine parameters relevant to achieving high yield, the imploding z-pinch mass has sufficient opacity to trap radiation giving rise to a dynamic hohlraum. The concept utilizes a 12 MJ, 54 MA z-pinch driver producing a capsule drive temperature exceeding 300 eV to realize a 550 MJ thermonuclear yield. They present the current high-yield design and its development that supports high-yield ICF with a z-pinch driven dynamic hohlraum.

  20. Study on the Theory and Technology of High Yield Culture of Compact Corn

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhi; ZHANG Rong-da; WU Sheng-li; SONG Bi; ZHANG Bang-kun; JIANG Long; WANG Song; HU Jian-feng

    2002-01-01

    Using the split plot and multi-quadric regressive orthogonal cross-course rotary combination design, corn variety Denghai 6's yield and yield components, important colony quality and physiological index, microclimate index in field and technical planting for high yield were studied. Cultivation for high yield showed that Denghai 6 had the great potential of increase yield. The average yield of two years was 12510kg/ha for 13.85ha, the highest grain yield (754.7m2) was 15477kg/ha. The climatic conditions can meet the needs for high yield during the whole growth stage of corn in the mountain area of Northwest Guizhou.

  1. Nuclear structure of sup 1 sup 2 sup 9 Te studied with (n, gamma), (d, p) and (d->, t) reactions

    CERN Document Server

    Wirth, H F; Tomandl, I; Honzatko, J; Bucurescu, D; Marginean, N; Ponomarev, V Yu; Hertenberger, R; Eisermann, Y; Graw, G

    2003-01-01

    The nuclear structure of sup 1 sup 2 sup 9 Te has been investigated with the sup 1 sup 2 sup 8 Te(n, gamma gamma) sup 1 sup 2 sup 9 Te reaction using thermal neutrons, with the sup 1 sup 2 sup 8 Te(d, p) sup 1 sup 2 sup 9 Te reaction at E sub d =24 MeV and E sub d =18 MeV, and with the sup 1 sup 3 sup 0 Te(d->, t) sup 1 sup 2 sup 9 Te reaction at E sub d =24 MeV. More than 110 levels were identified already below 3 MeV excitation energy, in most cases including spin, parity, and gamma decay. The neutron binding energy was determined to be 6082.42(11) keV. The thermal neutron capture cross sections to the ground state and to the 11/2 sup - isomer were found to be 0.165(20) b and 0.021(3) b, respectively. The mechanism of direct neutron capture was verified to play an important role in the sup 1 sup 2 sup 8 Te(n, gamma) sup 1 sup 2 sup 9 Te reaction. The experimental level scheme is compared with predictions of the Interacting Boson-Fermion Model (IBFM) and of the Quasiparticle Phonon Model (QPM).

  2. Electronic neutron sources for compensated porosity well logging

    Energy Technology Data Exchange (ETDEWEB)

    Chen, A.X., E-mail: axchen@sandia.gov [Sandia National Laboratories, Livermore, CA 94550 (United States); Antolak, A.J.; Leung, K.-N. [Sandia National Laboratories, Livermore, CA 94550 (United States)

    2012-08-21

    The viability of replacing Americium-Beryllium (Am-Be) radiological neutron sources in compensated porosity nuclear well logging tools with D-T or D-D accelerator-driven neutron sources is explored. The analysis consisted of developing a model for a typical well-logging borehole configuration and computing the helium-3 detector response to varying formation porosities using three different neutron sources (Am-Be, D-D, and D-T). The results indicate that, when normalized to the same source intensity, the use of a D-D neutron source has greater sensitivity for measuring the formation porosity than either an Am-Be or D-T source. The results of the study provide operational requirements that enable compensated porosity well logging with a compact, low power D-D neutron generator, which the current state-of-the-art indicates is technically achievable.

  3. 板栗丰产栽培技术%High-yield Cultivation Technology of Chestnuts

    Institute of Scientific and Technical Information of China (English)

    李明杰; 于海洋; 孙少娟; 吴岩

    2011-01-01

    In view of the biological characteristics of chestnuts, several key technical points of high-yield cultivation of chestnuts are presented.%针对板栗的生物学特性,对栗树的丰产栽培提出几项技术要点。

  4. 31 CFR 356.21 - How are awards at the high yield or discount rate calculated?

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false How are awards at the high yield or discount rate calculated? 356.21 Section 356.21 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY BUREAU OF THE PUBLIC DEBT SALE...

  5. Lab-on-Chip platform for high-yield electrofusion in droplets

    NARCIS (Netherlands)

    Schoeman, R.M.; Braak, ter P.M.; Bomer, J.G.; Berg, van den A.

    2014-01-01

    In this article, we present a microfluidic device, consisting of a microchannel structure in PDMS bonded to a glass substrate with recessed platinum electrodes. Our device is capable of successive high-yield single cell encapsulation in droplets, with additional droplet pairing, fusion, shrinkage an

  6. Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic Matter

    NARCIS (Netherlands)

    Logan, B.E.; Call, D.; Cheng, S.; Hamelers, H.V.M.; Sleutels, T.H.J.A.; Jeremiasse, A.W.; Rozendal, R.A.

    2008-01-01

    The use of electrochemically active bacteria to break down organic matter, combined with the addition of a small voltage (>0.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield of hydrogen gas. While microbial electrolysis was invented only a few

  7. Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic Matter

    NARCIS (Netherlands)

    Logan, B.E.; Call, D.; Cheng, S.; Hamelers, H.V.M.; Sleutels, T.H.J.A.; Jeremiasse, A.W.; Rozendal, R.A.

    2008-01-01

    The use of electrochemically active bacteria to break down organic matter, combined with the addition of a small voltage (>0.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield of hydrogen gas. While microbial electrolysis was invented only a few

  8. Improved forage strategies for high-yielding dairy cows in Vietnam : report of a workshop

    NARCIS (Netherlands)

    Wouters, A.P.; Lee, van der J.

    2013-01-01

    This report presents results of the workshop "Improved forage strategies for high-yielding dairy cows in Vietnam" which was held with Vietnamese stakeholders on January 17-18, 2013 in Ho Chi Minh City as part of the project "Forage and Grass Production for Dairy Development in Vietnam" funded by the

  9. Growth and development characteristics of super-high-yielding mid-season japonica rice

    Institute of Scientific and Technical Information of China (English)

    YANG Jianchang; DU Yong; WU Changfu; LIU Lijun; WANG Zhiqin; ZHU Qingsen

    2007-01-01

    Rice is one of the most important food crops in China.The realization of the super-high-yielding (SHY)type has great significance in ensuring food security in this country.This study investigated the growth and development characteristics of the super-high-yielding rice (grain yield>11 t/hm2).Four mid-season japonica rice cultivars (including lines):Lianjiajing 2,Huajing 5,0026 and 9823,were grown in the paddy field.Growth analysis was performed during the growth period,and yield components were determined at maturity.Results showed that SHY rice had more sipkelets per panicle and higher filled-grain percentage than the high-yielding rice (CK,grain yield 8.98-9.16 t/hm2).There was no significant difference in the 1 000-grain weight between the super-high-yielding and the CK.Super-high-yield rice exhib ited fewer tillers at the early growth stage (from transplanting to jointing),with a higher ratio of productive tillers to total tillers,when compared with the CK.The leaf area index (LAI),photosynthetic potential and dry matter accumulation were lower for the SHY rice than those for the CK at the early growth stage,and the differences were not significant between the two rice types at heading,but were greater in the former than the latter after heading.The root-shoot ratio at each growth stage,root bleedings from heading to maturity,grain-leaf ratio,translocation percentage of the matter from stems and sheaths and harvest index of super-high-yielding rice were greater than those of CK.The indexes for the growth and development of SHY mid-season rice population were suggested,i.e.total spikelets>4.5×104/m2,filled-grain percentage>90%,1 000-grain weight>26 g;ratio of productive tillers>80%,leaf area index at heading 7.5-8.0,photosynthetic potential during the whole growth period >22 t/hm2,harvest index>0.51;grain-leaf ratio (number of spikelets per cm2 leaf area)>0.58;root-shoot ratio at heading tion approaches and key cultivation techniques for raising the

  10. Calculations to support JET neutron yield calibration: Modelling of neutron emission from a compact DT neutron generator

    Science.gov (United States)

    Čufar, Aljaž; Batistoni, Paola; Conroy, Sean; Ghani, Zamir; Lengar, Igor; Milocco, Alberto; Packer, Lee; Pillon, Mario; Popovichev, Sergey; Snoj, Luka

    2017-03-01

    At the Joint European Torus (JET) the ex-vessel fission chambers and in-vessel activation detectors are used as the neutron production rate and neutron yield monitors respectively. In order to ensure that these detectors produce accurate measurements they need to be experimentally calibrated. A new calibration of neutron detectors to 14 MeV neutrons, resulting from deuterium-tritium (DT) plasmas, is planned at JET using a compact accelerator based neutron generator (NG) in which a D/T beam impinges on a solid target containing T/D, producing neutrons by DT fusion reactions. This paper presents the analysis that was performed to model the neutron source characteristics in terms of energy spectrum, angle-energy distribution and the effect of the neutron generator geometry. Different codes capable of simulating the accelerator based DT neutron sources are compared and sensitivities to uncertainties in the generator's internal structure analysed. The analysis was performed to support preparation to the experimental measurements performed to characterize the NG as a calibration source. Further extensive neutronics analyses, performed with this model of the NG, will be needed to support the neutron calibration experiments and take into account various differences between the calibration experiment and experiments using the plasma as a source of neutrons.

  11. Special nuclear material detection using pulsed neutron interrogation

    Science.gov (United States)

    Ruddy, Frank H.; Seidel, John G.; Flammang, Robert W.

    2007-04-01

    Pulsed neutron interrogation methods for detection of Special Nuclear Materials are being developed. Fast prompt neutrons from thermal neutron-induced fissions are detected in the time intervals following 100-μs neutron bursts from a pulsed D-T neutron generator operating at 1000 pulses per second. Silicon Carbide semiconductor neutron detectors are used to detect fission neutrons in the 30-840 μs time intervals following each 14-MeV D-T neutron pulse. Optimization of the neutron detectors has led to dramatic reduction of detector background and improvement of the signal-to-noise ratio for Special Nuclear Material detection. Detection of Special Nuclear Materials in the presence of lead, cadmium and plywood shielding has been demonstrated. Generally, the introduction of shielding leads to short thermal neutron die-away times of 100-200 μs or less. The pulsed neutron interrogation method developed allows detection of the neutron signal even when the die-away time is less than 100 μs.

  12. High-Yield Solvothermal Formation of Magnetic CoPt Alloy Nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zongtao [ORNL; Blom, Douglas Allen [ORNL; Gai, Zheng [ORNL; Thompson, James R [ORNL; Shen, Jian [ORNL; Dai, Sheng [ORNL

    2003-01-01

    One-dimensional (1D) magnetic nanomaterials have attracted much attention recently because of their applications in magnetic recording and spintronics. Nevertheless, it remains a challenge to prepare free-standing magnetic nanowires in high yield. This Communication reports the successful high-yield synthesis of an interesting 1D ferromagnetic CoPt alloy by direct decomposition of platinum acetylacetonate and cobalt carbonyl compound in ethylenediamine solvent through a solvothermal reaction. The CoPt alloy nanowires obtained have a tunable diameter of 10-50 nm and a length along the longitudinal axis of up to several microns, depending on crystallization temperature and reaction time. A unique formation mechanism involving coarsening and ripening under solvothermal conditions was discovered. This research opens new opportunities in synthesizing nanomaterials through low-temperature solvothermal processes.

  13. Controlled Fabrication of High-Yield CdS Nanostructures by Compartment Arrangement

    Directory of Open Access Journals (Sweden)

    Joshua M. Green

    2008-01-01

    Full Text Available High-yield, high-purity CdS nanostructures were synthesized in a turf-like configuration using an improved vapor-liquid-solid method. To increase the yield, a compartment arrangement was employed. The specific kind of nanostructure fabricated was found to be directly dependent on the temperature in the compartment. Along with the high-yield growth of CdS nanorods, nanowires, and nanobelts, intertwined structures were also observed, and the electron field emission property of the intertwined structures was investigated and compared with that of other type of nanostructures. Photoluminescence measurements at 10 K showed a peak emission from the CdS nanostructures at 485 nm.

  14. [Molecular ecological basis of high-yielding formation of rice and its application].

    Science.gov (United States)

    Lin, Wenxiong; Liang, Kangjing; Guo, Yuchun; He, Huaqin; Wang, Jingyuan; Liang, Yiyuan; Chen, Fangyu

    2003-12-01

    This paper introduced the developmental genetics and its molecular ecological basis of high yielding formation of rice in the past decade, and analyzed the advantage and the shortage of comparative physiological approach traditionally used in the research work on crop cultivation. It was emphasized to actively introduce the research contents and its methodology from relative disciplines to deeply understand the scientific issue, and suggested that the key to realize stable and high yielding of rice was to develop a rational cultivation system based on the properties of genetic effects on the traits in different developmental stages by controlling and regulating the traits governed by dominant effect genes and additive effect genes x environment in same direction, which was considered as the main characteristics and the technological innovation of modern crop genetic ecological cultivation science. Finally, the development trend of crop cultivation science shifting to molecular crop cultivation science was predicted and discussed.

  15. High yield fabrication of chemically reduced graphene oxide field effect transistors by dielectrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Joung, Daeha; Chunder, A; Zhai, Lei; Khondaker, Saiful I, E-mail: saiful@mail.ucf.edu [Nanoscience Technology Center, University of Central Florida, Orlando, FL 32826 (United States)

    2010-04-23

    We demonstrate high yield fabrication of field effect transistors (FET) using chemically reduced graphene oxide (RGO) sheets. The RGO sheets suspended in water were assembled between prefabricated gold source and drain electrodes using ac dielectrophoresis. With the application of a backgate voltage, 60% of the devices showed p-type FET behavior, while the remaining 40% showed ambipolar behavior. After mild thermal annealing at 200 deg. C, all ambipolar RGO FET remained ambipolar with increased hole and electron mobility, while 60% of the p-type RGO devices were transformed to ambipolar. The maximum hole and electron mobilities of the devices were 4.0 and 1.5 cm{sup 2} V{sup -1} s{sup -1} respectively. High yield assembly of chemically derived RGO FET will have significant impact in scaled up fabrication of graphene based nanoelectronic devices.

  16. Flow “Fine” Synthesis: High Yielding and Selective Organic Synthesis by Flow Methods

    Science.gov (United States)

    2015-01-01

    Abstract The concept of flow “fine” synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow “fine” synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be applicable for the production of simple gasses but that it is difficult to apply to the synthesis of complex molecules such as natural products and APIs. Therefore, organic synthesis of such complex molecules has been conducted by batch methods. On the other hand, syntheses and reactions that attain high yields and high selectivities by flow methods are increasingly reported. Flow methods are leading candidates for the next generation of manufacturing methods that can mitigate environmental concerns toward sustainable society. PMID:26337828

  17. Prediction of failure strain and burst pressure in high yield-to-tensile strength ratio linepipe

    Energy Technology Data Exchange (ETDEWEB)

    Law, M. [Institute of Materials and Engineering Science, Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia)]. E-mail: mlx@ansto.gov.au; Bowie, G. [BlueScope Steel Ltd., Level 11, 120 Collins St, Melbourne, Victoria 3000 (Australia)

    2007-08-15

    Failure pressures and strains were predicted for a number of burst tests as part of a project to explore failure strain in high yield-to-tensile strength ratio linepipe. Twenty-three methods for predicting the burst pressure and six methods of predicting the failure strain are compared with test results. Several methods were identified which gave accurate and reliable estimates of burst pressure. No method of accurately predicting the failure strain was found, though the best was noted.

  18. Fast and green synthesis of biologically important quinoxalines with high yields in water

    Directory of Open Access Journals (Sweden)

    Hossein Ghafuri

    2014-06-01

    Full Text Available Optimal method were developed for the green synthesis of quinoxaline derivatives based on the highly efficient and simple condensation reaction of various aromatic 1,2-diketones and 1,2-diamines in nearly quantitative yields in water. In this method we did not use any catalyst. The very mild reaction conditions, the high yields of the products, and the absence of any catalyst make this methodology an efficient and green route for synthesis of quinoxalines.

  19. Extracting DNA from 'jaws': High yield and quality from archived tiger shark (Galeocerdo cuvier) skeletal material

    DEFF Research Database (Denmark)

    Eg Nielsen, Einar; Morgan, J. A T; Maher, S. L.

    2017-01-01

    of tiger sharks (Galeocerdo cuvier). Protocols were compared for DNA yield and quality using a qPCR approach. For jaw swarf, all methods provided relatively high DNA yield and quality, while large differences in yield between protocols were observed for vertebrae. Similar results were obtained from samples...... and vertebrae are potential high-yield sources of DNA for genomic-scale analysis. It also highlights that even for similar tissue types, a careful evaluation of extraction protocols can vastly improve DNA yield....

  20. Mutagenesis and Screening of High Yield Xylanase Production Strain of Aspergillus usamii by Microwave Irradiation

    Institute of Scientific and Technical Information of China (English)

    李永泉; 陈时飞; 岑沛霖

    2003-01-01

    A high yield xylanase producing strain, A. usamii L336-23, was screened out from its parent strain A.usamii L336 after microwave irradiation. Its productivity of xylanase activity increased by 35.7% from 21000μ·m1-1 to 28500μ·m1-1 and was stable after frequent subcultures and storage for more than two months.The mechanism of microwave mutation was also discussed.

  1. What's D&T For? Gathering and Comparing the Values of Design and Technology Academics and Trainee Teachers

    Science.gov (United States)

    Hardy, Alison

    2015-01-01

    Some who read and research about Design & Technology (D&T) would say that the concept of value is key to understanding and defining D&T. Closer inspection reveals though that there are two ways in which values are defined in D&T: how values are taught and learnt about in D&T to use them to make judgments in D&T lessons, and…

  2. Surrogate models for identifying robust, high yield regions of parameter space for ICF implosion simulations

    Science.gov (United States)

    Humbird, Kelli; Peterson, J. Luc; Brandon, Scott; Field, John; Nora, Ryan; Spears, Brian

    2016-10-01

    Next-generation supercomputer architecture and in-transit data analysis have been used to create a large collection of 2-D ICF capsule implosion simulations. The database includes metrics for approximately 60,000 implosions, with x-ray images and detailed physics parameters available for over 20,000 simulations. To map and explore this large database, surrogate models for numerous quantities of interest are built using supervised machine learning algorithms. Response surfaces constructed using the predictive capabilities of the surrogates allow for continuous exploration of parameter space without requiring additional simulations. High performing regions of the input space are identified to guide the design of future experiments. In particular, a model for the yield built using a random forest regression algorithm has a cross validation score of 94.3% and is consistently conservative for high yield predictions. The model is used to search for robust volumes of parameter space where high yields are expected, even given variations in other input parameters. Surrogates for additional quantities of interest relevant to ignition are used to further characterize the high yield regions. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, Lawrence Livermore National Security, LLC. LLNL-ABS-697277.

  3. A high throughput DNA extraction method with high yield and quality

    Directory of Open Access Journals (Sweden)

    Xin Zhanguo

    2012-07-01

    Full Text Available Abstract Background Preparation of large quantity and high quality genomic DNA from a large number of plant samples is a major bottleneck for most genetic and genomic analyses, such as, genetic mapping, TILLING (Targeting Induced Local Lesion IN Genome, and next-generation sequencing directly from sheared genomic DNA. A variety of DNA preparation methods and commercial kits are available. However, they are either low throughput, low yield, or costly. Here, we describe a method for high throughput genomic DNA isolation from sorghum [Sorghum bicolor (L. Moench] leaves and dry seeds with high yield, high quality, and affordable cost. Results We developed a high throughput DNA isolation method by combining a high yield CTAB extraction method with an improved cleanup procedure based on MagAttract kit. The method yielded large quantity and high quality DNA from both lyophilized sorghum leaves and dry seeds. The DNA yield was improved by nearly 30 fold with 4 times less consumption of MagAttract beads. The method can also be used in other plant species, including cotton leaves and pine needles. Conclusion A high throughput system for DNA extraction from sorghum leaves and seeds was developed and validated. The main advantages of the method are low cost, high yield, high quality, and high throughput. One person can process two 96-well plates in a working day at a cost of $0.10 per sample of magnetic beads plus other consumables that other methods will also need.

  4. Some critical considerations on rice high-yielding breeding in China

    Institute of Scientific and Technical Information of China (English)

    ZHU Lihong

    2007-01-01

    Views and comments concerning rice highyielding breeding in China had been touched upon:(1) historical development of rice breeding in China and its prominent contributions recounted;current challenges evolved from rapid population increase,erosion of key natural resources and socioeconomic changes envisaged;(2) concept of extra or super high-yielding rice breeding and related ideas embraced nowadays in the main rice-producing countries assessed;the conception of so-called superrice in China could have been misled and misunderstood,and no substantial genetical differences could be affirmed yet between superrice and modern high-yielding rice;(3) two strategical approaches of rice production and breeding in China would have been persistent in the construction of most favorable-to-growth rice fields to plant rice varieties with high-yielding potentiality as well as renovation and rejuvenation of less favorable rice fields to plant most adaptableto-ecoenvironment varieties with promising productivity;in addition,breeding for rice varieties compatible with the specific rice regions ridden by adverse ecoenvironments;(4) overview of the relationship between the development of genetical researches and the perspective of rice breeding;integration of the classical genetical principles and breeding methods and techniques wherefrom with molecular biotechniques underscored.Finally,appeal to the breeders to adhere to due attentions to the development of genetics and promote pragmatism and traditional ethic solemnly so as to live up to implementing the national rice breeding mandates.

  5. Ultra-broadband nonlinear saturable absorption of high-yield MoS2 nanosheets.

    Science.gov (United States)

    Wei, Rongfei; Zhang, Hang; Hu, Zhongliang; Qiao, Tian; He, Xin; Guo, Qiangbing; Tian, Xiangling; Chen, Zhi; Qiu, Jianrong

    2016-07-29

    High-yield MoS2 nanosheets with strong nonlinear optical (NLO) responses in a broad near-infrared range were synthesized by a facile hydrothermal method. The observation of saturable absorption, which was excited by the light with photon energy smaller than the gap energy of MoS2, can be attributed to the enhancement of the hybridization between the Mo d-orbital and S p-orbital by the oxygen incorporation into MoS2. High-yield MoS2 nanosheets with high modulation depth and large saturable intensity generated a stable, passively Q-switched fiber laser pulse at 1.56 μm. The high output power of 1.08 mW can be attained under a very low pump power of 30.87 mW. Compared to recently reported passively Q-switched fiber lasers utilizing exfoliated MoS2 nanosheets, the efficiency of the laser for our passive Q-switching operation is larger and reaches 3.50%. This research may extend the understanding on the NLO properties of MoS2 and indicate the feasibility of the high-yield MoS2 nanosheets to passively Q-switched fiber laser effectively at low pump strengths.

  6. Characterization of high-yield performance as affected by genotype and environment in rice

    Institute of Scientific and Technical Information of China (English)

    Song CHEN; Fang-rong ZENG; Zong-zhi PAO; Guo-ping ZHANG

    2008-01-01

    We characterized yield-relevant characters and their variations over genotypes and environments (locations and years) by examining two rice varieties (9746 and Jinfeng) with high yield potential.9746 and Jinfeng were planted in two locations of Shanghai,China,during 2005 and 2006.The results show that there was a large variation in grain yield between locations and years.The realization of high yield potential for the two types of rice was closely related to the improved sink size,such as more panicles per square meter or grains per panicle.Stem and leaf biomasses were mainly accumulated from tillering stage to heading stage,and showed slow decline during grain filling.Meanwhile,some photosynthetic characters including net photosynthesis rate (Pn),leaf area index (LAI),specific leaf area (SLA),fluorescence parameter (maximum quantum yield of PSII,Fv/Fm),chlorophyll content (expressed as SPAD value),as well as nutrient (N,P,K) uptake were also measured to determine their variations over genotypes and environments and their relationships with grain yield.Although there were significant differences between years or locations for most measurements,SLA at tillering and heading stages,Fv/Fm and LAI at heading stage,stem biomass at heading and maturity stages,and leaf nitrogen concentration at tillering and heading stages remained little changed,indicating their pos-sible applications as selectable characters in breeding programs.It was also found that stem nitrogen accumulation at tillering stage is one of the most important and stable traits for high yield formation.

  7. A New High-Yielding Two-line Hybrid Rice Variety - Peiliang You 981

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ Peiliang You 981 (also called 98 Guangzhi 1 or Peiliang You Guangzhi 1) is a late-season two-line indica hybrid rice variety with high yield and late maturity. Pei'ai 64S is the female parent and R981 (Guang 1) is the male parent of Peiliang You 981. The hybrid showed its characters of high and stable yield and wide adaptability in the variety trials and demonstration production in the recent years, and it was released in March 2002 by Hunan Crop Varieties Release Committee.

  8. High confinement, high yield Si3N4 waveguides for nonlinear optical application

    CERN Document Server

    Epping, Jörn P; Mateman, Richard; Leinse, Arne; Heideman, René G; van Rees, Albert; van der Slot, Peter J M; Lee, Chris J; Boller, Klaus-J

    2014-01-01

    In this paper we present a novel fabrication technique for silicon nitride (Si3N4) waveguides with a thickness of up to 900 nm, which are suitable for nonlinear optical applications. The fabrication method is based on etching trenches in thermally oxidized silicon and filling the trenches with Si3N4. Using this technique no stress-induced cracks in the Si3N4 layer were observed resulting in a high yield of devices on the wafer. The propagation losses of the obtained waveguides were measured to be as low as 0.4 dB/cm at a wavelength of around 1550 nm.

  9. Property Evaluation Method Using Spherical Indentation for High-Yield Strength Materials

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Youngsick; Marimuthu, Karuppasamy Pandian; Lee, Hyungyil [Sogang Univ., Seoul (Korea, Republic of); Lee, Jin Haeng [KAERI, Daejeon (Korea, Republic of)

    2015-11-15

    In this paper, we propose a method to evaluate the material properties of high-yield strength materials exceeding 10GPa from spherical indentation. Using a regression equation considering four indentation variables, we map the load displacement relation into a stress-strain relation. To calculate the properties of high-strength materials, we then write a program that produces material properties using the loading / unloading data from the indentation test. The errors in material properties computed by the program are within 0.3, 0.8, and 6.4 for the elastic modulus, yield strength, and hardening coefficient, respectively.

  10. Property evaluation method using spherical indentation for high-yield strength materials

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Sick; Marimuthu, Karuppasamy Pandian; Lee, Hyung Yil [Dept. of Mechanical Engineering, Sogang University, Seoul (Korea, Republic of); Lee, Jin Haeng [Reactor Mechanical Engineering Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-11-15

    In this paper, we propose a method to evaluate the material properties of high-yield strength materials exceeding 10 GPa from spherical indentation. Using a regression equation considering four indentation variables, we map the load displacement relation into a stress-strain relation. To calculate the properties of high-strength materials, we then write a program that produces material properties using the loading / unloading data from the indentation test. The errors in material properties computed by the program are within 0.3, 0.8, and 6.4 for the elastic modulus, yield strength, and hardening coefficient, respectively.

  11. Root-determined hypernodulation mutant of Lotus japonicus shows high-yielding characteristics.

    Science.gov (United States)

    Yokota, Keisuke; Li, Yong Yi; Hisatomi, Masahiro; Wang, Yanxu; Ishikawa, Kaori; Liu, Chi-Te; Suzuki, Shino; Aonuma, Kho; Aono, Toshihiro; Nakamoto, Tomomi; Oyaizu, Hiroshi

    2009-07-01

    Here we report the phenotypic characteristics of a novel hypernodulation mutant, Ljrdh1 (root-determined hypernodulation 1) of Lotus japonicus. At 12 weeks after rhizobial inoculation, there were no differences between the growth of Ljrdh1 and, wild-type. However, Ljrdh1 showed 2 to 3 times higher nitrogen-fixing activity, and seed and pod yields, were approximately 50% higher than the wild-type. This is the first report of a legume hypernodulation mutant showing normal growth and a high-yielding characteristic under optimal cultivation conditions.

  12. Study on Plant Morphological Traits and Production Characteristics of Super High-Yielding Soybean

    Institute of Scientific and Technical Information of China (English)

    AO Xue; XIE Fu-ti; HAN Xiao-ri; ZHAO Ming-hui; ZHU Qian; LI Jie; ZHANG Hui-jun; WANG Hai-ying; YU Cui-mei; LI Chun-hong; YAO Xing-dong

    2013-01-01

    Super high-yielding soybean cultivar Liaodou 14, soybean cultivars from Ohio in the United States, and the common soybean cultivars from Liaoning Province, China, with similar geographic latitudes and identical pod-bearing habits were used as the study materials for a comparison of morphological traits and production characteristics to provide a theoretical basis for the breeding of improved super high-yielding soybean cultivars. Using a randomized block design, different soybean cultivars from the same latitude were compared under conventional and unconventional treatments for their production characteristics, including morphological traits, leaf area index (LAI), net photosynthesis rate, and dry matter accumulation. The specific characteristics of the super high-yielding soybean cultivar Liaodou 14 were analyzed. The results showed that the plant height of Liaodou 14 was significantly lower than that of the common cultivars from Liaoning, whereas the number of its main-stem nodes was higher than that of the cultivars from Ohio or Liaoning. A high pod density was observed in Liaodou 14 under conventional treatments. Under both conventional and unconventional treatments, the branch number of Liaodou 14 was markedly higher than that of the common cultivars from Liaoning, and its branch length and leaf inclination angle were significantly higher than those of common cultivars from Liaoning or Ohio. Only small changes in the leaf inclination angle were observed in Liaodou 14 treated with conventional or unconventional methods. Under each treatment, Liaodou 14 exhibited the lowest amplitude of reduction in SPAD values and net photosynthesis rates from the grain-filling to ripening stages;the cultivars from Ohio and the common cultivars from Liaoning exhibited more significant reductions. Liaodou 14 reached its peak LAI later than the other cultivars but maintained its LAI at a higher level for a longer duration. Under both conventional and unconventional treatments

  13. Problems in Fast-growing and High-yield Plantation Ecosystem Management and Their Countermeasures in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The paper analyzed the basic characteristics of fast-growing and high-yield plantation, classified and identified the ecological problems in its development, and finally proposed the basic principles and corresponding technical measures for fast-growing and high-yield plantation ecosystem management based on these problems.

  14. Compact Neutron Generators for Medical, Home Land Security, and Planetary Exploration

    CERN Document Server

    Reijonen, Jani

    2005-01-01

    The Plasma and Ion Source Technology Group at Lawrence Berkeley National Laboratory has developed various types of advanced D-D (neutron energy 2.5 MeV), D-T (14 MeV) and T-T (0 - 9 MeV) neutron generators for wide range of applications. These applications include medical (Boron Neutron Capture Therapy), homeland security (Prompt Gamma Activation Analysis, Fast Neutron Activation Analysis and Pulsed Fast Neutron Transmission Spectroscopy) and planetary exploration in form of neutron based, sub-surface hydrogen detection systems. These neutron generators utilize RF induction discharge to ionize the deuterium/tritium gas. This discharge method provides high plasma density for high output current, high atomic species from molecular gases, long life operation and versatility for various discharge chamber geometries. Three main neutron generator developments are discussed here: high neutron output co-axial neutron generator for BNCT applications, point neutron generator for security applications, compact and sub-c...

  15. Extractive Fermentation of Sugarcane Juice to Produce High Yield and Productivity of Bioethanol

    Science.gov (United States)

    Rofiqah, U.; Widjaja, T.; Altway, A.; Bramantyo, A.

    2017-04-01

    Ethanol production by batch fermentation requires a simple process and it is widely used. Batch fermentation produces ethanol with low yield and productivity due to the accumulation of ethanol in which poisons microorganisms in the fermenter. Extractive fermentation technique is applied to solve the microorganism inhibition problem by ethanol. Extractive fermentation technique can produce ethanol with high yield and productivity. In this process raffinate still, contains much sugar because conversion in the fermentation process is not perfect. Thus, to enhance ethanol yield and productivity, recycle system is applied by returning the raffinate from the extraction process to the fermentation process. This raffinate also contains ethanol which would inhibit the performance of microorganisms in producing ethanol during the fermentation process. Therefore, this study aims to find the optimum condition for the amount of solvent to broth ratio (S: B) and recycle to fresh feed ratio (R: F) which enter the fermenter to produce high yield and productivity. This research was carried out by experiment. In the experiment, sugarcane juice was fermented using Zymomonasmobilis mutant. The fermentation broth was extracted using amyl alcohol. The process was integrated with the recycle system by varying the recycle ratio. The highest yield and productivity is 22.3901% and 103.115 g / L.h respectively, obtained in a process that uses recycle to fresh feed ratio (R: F) of 50:50 and solvents to both ratio of 1.

  16. Surface studies and implanted helium measurements following NOVA high-yield DT experiments

    Energy Technology Data Exchange (ETDEWEB)

    Stoyer, M.A.; Hudson, G.B.

    1997-02-18

    This paper presents the results of three March 6, 1996 direct-drive high-yield DT NOVA experiments and provides `proof-of-principal` results for the quantitative measurement of energetic He ions. Semiconductor quality Si wafers and an amorphous carbon wafer were exposed to NOVA high-yield implosions. Surface damage was sub-micron in general, although the surface ablation was slightly greater for the carbon wafer than for the Si wafers. Melting of a thin ({approx} 0.1{mu}) layer of Si was evident from microscopic investigation. Electron microscopy indicated melted blobs of many different metals (e.g. Al, Au, Ta, Fe alloys, Cu and even Cd) on the surfaces. The yield measured by determining the numbers of atoms of implanted {sup 4}He and {sup 3}He indicate the number of DT fusions to be 9.1({plus_minus}2.3) X 10{sup 12} and DD fusions to be 4.8({plus_minus}1.0) x 10{sup 10}, respectively. The helium DT fusion yield is slightly lower than that of the Cu activation measurement, which was 1.3({plus_minus}0.l) x 10{sup 13} DT fusions.

  17. Genome shuffling and ribosome engineering of Streptomyces actuosus for high-yield nosiheptide production.

    Science.gov (United States)

    Wang, Qingling; Zhang, Dong; Li, Yudong; Zhang, Fuming; Wang, Cao; Liang, Xinle

    2014-07-01

    Nosiheptide is one of the EU-approved sulfur-containing peptides in feed industry to inhibit the growth of the majority of Gram-positive bacteria. The main purpose of this study is directed to breed the high nosiheptide-producers by genome shuffling and ribosome engineering in Streptomyces actuosus AW7. The starting population for shuffling was generated by combining (60)Coγ-irradiation with LiCl mutagenesis treatments on the spores. After four rounds of protoplast fusion exposed to streptomycin as adaptive pressure, a high-yield recombinant strain D92 was obtained. In a 10-L fermenter, nosiheptide production reached 1.54 g/L which was 9.20-fold compared to that of the parental strain. Hyphae development, metabolic process, and ribosomal protein S12 sequence were investigated to characterize the differentiation among the recombinants. Several mutations in S12 were believed to be responsible to streptomycin resistance in the tested strain. The results demonstrated that the combination of genome shuffling and ribosome engineering is an efficient approach to breed high-yield industrial strains.

  18. High-yielding Cultivation and Fertilization Technology of Lvhan No.1 in Angola

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] The aim was to research high-yielding cultivation and fertilization technology for Lvhan No.l, a new Chinese rice cultivar, in Angola. [Method] In rainy season of 2012, high-yielding cultivation and fertilization technology of Lvhan No.l, a new cultivar of earlier ripe and drought resistant rice, was researched in CATETE farm of Luanda suburb with pot experiment method. [Result] In CATETE farm, Lvhan No.1 rice were directly sown in black clay and the rice can be significantly improved in plant height, grain weight of single plant, biological yield of single plant, ear length, total grain number per ear, number of filled grain per ear and thousand seed weight, as well as economic coefficient and ratio of grain to straw, if applied with base fertilizer made up of DAP (N:P2Os=14:43), or compound fertilizer of N, P and K (N:P2Os:K~O=15:15:15) and with Duannai fertilizer and ear-grain fertilizer made up of urea. If DAP is taken as base fertilizer, the optimal quantity is 300 kg/hm2. If compound fertilizer of N, P and K is taken as base fertilizer, the optimal quantity is 450 kg/hm2, but urea at 75 kg/hm2 should be applied as Duannai fertilizer and ear- grain fertilizer, respectively, on time. [Conclusion] The research provides technical ref- erences for planting of Chinese rice cultivars in Angola.

  19. Use of Iron Powder to Obtain High Yields of Leptothrix Sheaths in Culture

    Directory of Open Access Journals (Sweden)

    Tomoko Suzuki

    2015-06-01

    Full Text Available The Leptothrix species, Fe-oxidizing bacteria, produce an extracellular, microtubular sheath with a complicated organic–inorganic hybrid nature. We have discovered diverse industrial functions for this material, e.g., electrode material for Li-ion batteries, catalyst enhancers, pigments, plant growth promoters, and plant protectants. To consistently obtain material with the qualitative and quantitative stability needed for industrial applications, we focused on developing an optimum culture system for sheath synthesis by the Leptothrix sp. strain OUMS1. Although we have used Fe plates as an Fe source in the liquid silicon-glucose-peptone medium (SGP, the plates do not yield a consistent quality or precise mass, and formation of Fe-encrusted sheath is restricted to a surface of the plates, which limits harvest yield. In this study, to obtain a high yield of sheaths, we cultured OUMS1 in SGP supplemented with Fe powders. The addition of Fe powders to the medium (up to 14.0 g/L did not adversely influence growth of OUMS1. The final yield of sheaths was about 10-fold greater than in the Fe plate culture. The sheaths also maintained a microtubular form and crystalline texture similar to those produced on Fe plates in SGP. The results proved the usefulness of Fe powder for consistently high yields of Fe-encrusted sheaths of stable quality.

  20. Flow "Fine" Synthesis: High Yielding and Selective Organic Synthesis by Flow Methods.

    Science.gov (United States)

    Kobayashi, Shū

    2016-02-18

    The concept of flow "fine" synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow "fine" synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be applicable for the production of simple gasses but that it is difficult to apply to the synthesis of complex molecules such as natural products and APIs. Therefore, organic synthesis of such complex molecules has been conducted by batch methods. On the other hand, syntheses and reactions that attain high yields and high selectivities by flow methods are increasingly reported. Flow methods are leading candidates for the next generation of manufacturing methods that can mitigate environmental concerns toward sustainable society. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  1. Estimation of the {alpha} particles and neutron distribution generated during a fusion reaction; Evaluation de la distribution des particules {alpha} et des neutrons issus de la reaction de fusion

    Energy Technology Data Exchange (ETDEWEB)

    Dellacherie, S.

    1997-12-01

    The respective distributions (or density probabilities) of {alpha} particles and neutrons have been modeled using a Monte-Carlo method for the thermonuclear fusion reaction D + T {yields} {alpha} + n + 17.6 MeV. (N.T.).

  2. Spectrum shaping of accelerator-based neutron beams for BNCT

    CERN Document Server

    Montagnini, B; Esposito, J; Giusti, V; Mattioda, F; Varone, R

    2002-01-01

    We describe Monte Carlo simulations of three facilities for the production of epithermal neutrons for Boron Neutron Capture Therapy (BNCT) and examine general aspects and problems of designing the spectrum-shaping assemblies to be used with these neutron sources. The first facility is based on an accelerator-driven low-power subcritical reactor, operating as a neutron amplifier. The other two facilities have no amplifier and rely entirely on their primary sources, a D-T fusion reaction device and a conventional 2.5 MeV proton accelerator with a Li target, respectively.

  3. High-yield synthesis of bioactive ethyl cinnamate by enzymatic esterification of cinnamic acid.

    Science.gov (United States)

    Wang, Yun; Zhang, Dong-Hao; Zhang, Jiang-Yan; Chen, Na; Zhi, Gao-Ying

    2016-01-01

    In this paper, Lipozyme TLIM-catalyzed synthesis of ethyl cinnamate through esterification of cinnamic acid with ethanol was studied. In order to increase the yield of ethyl cinnamate, several media, including acetone, isooctane, DMSO and solvent-free medium, were investigated in this reaction. The reaction showed a high yield by using isooctane as reaction medium, which was found to be much higher than the yields reported previously. Furthermore, several parameters such as shaking rate, water activity, reaction temperature, substrate molar ratio and enzyme loading had important influences on this reaction. For instance, when temperature increased from 10 to 50 °C, the initial reaction rate increased by 18 times and the yield of ethyl cinnamate increased by 6.2 times. Under the optimum conditions, lipase-catalyzed synthesis of ethyl cinnamate gave a maximum yield of 99%, which was of general interest for developing industrial processes for the preparation of ethyl cinnamate.

  4. High Yield Synthesis of Aspect Ratio Controlled Graphenic Materials from Anthracite Coal in Supercritical Fluids.

    Science.gov (United States)

    Sasikala, Suchithra Padmajan; Henry, Lucile; Yesilbag Tonga, Gulen; Huang, Kai; Das, Riddha; Giroire, Baptiste; Marre, Samuel; Rotello, Vincent M; Penicaud, Alain; Poulin, Philippe; Aymonier, Cyril

    2016-05-24

    This paper rationalizes the green and scalable synthesis of graphenic materials of different aspect ratios using anthracite coal as a single source material under different supercritical environments. Single layer, monodisperse graphene oxide quantum dots (GQDs) are obtained at high yield (55 wt %) from anthracite coal in supercritical water. The obtained GQDs are ∼3 nm in lateral size and display a high fluorescence quantum yield of 28%. They show high cell viability and are readily used for imaging cancer cells. In an analogous experiment, high aspect ratio graphenic materials with ribbon-like morphology (GRs) are synthesized from the same source material in supercritical ethanol at a yield of 6.4 wt %. A thin film of GRs with 68% transparency shows a surface resistance of 9.3 kΩ/sq. This is apparently the demonstration of anthracite coal as a source for electrically conductive graphenic materials.

  5. Improvement of bleached wheat straw pulp properties by using aspen high-yield pulp.

    Science.gov (United States)

    Zhang, Hongjie; Li, Jianguo; Hu, Huiren; He, Zhibin; Ni, Yonghao

    2012-09-01

    The bleached wheat straw pulp (BWSP) accounts for about 25% of the virgin fiber supply in the Chinese Pulp and Paper Industry. As a non-wood chemical pulp, BWSP is known to have low bulk, low light scattering coefficient and poor drainage due to its high content of parenchyma cells. In this study, a high-quality aspen high-yield pulp (HYP) was used to improve the BWSP properties at the laboratory scale. The results indicate that adding 5-20% aspen HYP into unrefined or refined BWSP can minimize many of the drawbacks associated with the BWSP: improving its drainage, bulk, light scattering coefficient and opacity. The addition of a small amount (up to 20%) of aspen HYP can also significantly increase the tear index of BWSP with only a slight decrease of the tensile index.

  6. High yield recombinant production of a self-assembling polycationic peptide for silica biomineralization.

    Science.gov (United States)

    Zerfaß, Christian; Braukmann, Sandra; Nietzsche, Sandor; Hobe, Stephan; Paulsen, Harald

    2015-04-01

    We report the recombinant bacterial expression and purification at high yields of a polycationic oligopeptide, P5S3. The sequence of P5S3 was inspired by a diatom silaffin, a silica precipitating peptide. Like its native model, P5S3 exhibits silica biomineralizing activity, but furthermore has unusual self-assembling properties. P5S3 is efficiently expressed in Escherichia coli as fusion with ketosteroid isomerase (KSI), which causes deposition in inclusion bodies. After breaking the fusion by cyanogen bromide reaction, P5S3 was purified by cation exchange chromatography, taking advantage of the exceptionally high content of basic amino acids. The numerous cationic charges do not prevent, but may even promote counterion-independent self-assembly which in turn leads to silica precipitation. Enzymatic phosphorylation, a common modification in native silica biomineralizing peptides, can be used to modify the precipitation activity.

  7. Improvement of production of high-yield poplar varieties seedlings by mycorrhiza application

    Directory of Open Access Journals (Sweden)

    Galić Zoran A.

    2007-01-01

    Full Text Available Research related to the effects of treatment by mycorrhiza preparations Ectovit, Rhodovit (preparations Symbio-m Ltd., Czech Rep. and their combination on growth of four high-yield poplar clones of Populus deltoides and one variety of Populus x euramericana are presented in this paper. In order to make more accurate assessment of mycorrhiza effect, soil characteristics such as morphology, texture and chemical composition were determined. The study results indicate that mycorrhized cuttings had the same or the better survival in all the study clones compared to the control. The application of the preparation Ectovit and Rhodovit resulted averagely in the first class planting stock of all the study clones. The combination of the preparations Ectovit and Rhodovit produced averagely the first class planting stock only of the clone Populus x euramericana.

  8. Extracting DNA from 'jaws': High yield and quality from archived tiger shark (Galeocerdo cuvier) skeletal material

    DEFF Research Database (Denmark)

    Eg Nielsen, Einar; Morgan, J. A T; Maher, S. L.

    2016-01-01

    Archived specimens are highly valuable sources of DNA for retrospective genetic/genomic analysis. However, often limited effort has been made to evaluate and optimize extraction methods, which may be crucial for downstream applications. Here, we assessed and optimized the usefulness of abundant...... archived skeletal material from sharks as a source of DNA for temporal genomic studies. Six different methods for DNA extraction, encompassing two different commercial kits and three different protocols, were applied to material, so-called bio-swarf, from contemporary and archived jaws and vertebrae...... and vertebrae are potential high-yield sources of DNA for genomic-scale analysis. It also highlights that even for similar tissue types, a careful evaluation of extraction protocols can vastly improve DNA yield....

  9. High-yield synthesis of silicon carbide nanowires by solar and lamp ablation

    Science.gov (United States)

    Lu, Hai-bo; Chan, Benjamin C. Y.; Wang, Xiaolin; Tong Chua, Hui; Raston, Colin L.; Albu-Yaron, Ana; Levy, Moshe; Popowitz-Biro, Ronit; Tenne, Reshef; Feuermann, Daniel; Gordon, Jeffrey M.

    2013-08-01

    We report a reasonably high yield (∼50%) synthesis of silicon carbide (SiC) nanowires from silicon oxides and carbon in vacuum, by novel solar and lamp photothermal ablation methods that obviate the need for catalysis, and allow relatively short reaction times (∼10 min) in a nominally one-step process that does not involve toxic reagents. The one-dimensional core/shell β-SiC/SiOx nanostructures—characterized by SEM, TEM, HRTEM, SAED, XRD and EDS—are typically several microns long, with core and outer diameters of about 10 and 30 nm, respectively. HRTEM revealed additional distinctive nanoscale structures that also shed light on the formation pathways.

  10. Catalytic oxidative conversion of cellulosic biomass to formic acid and acetic acid with exceptionally high yields

    KAUST Repository

    Zhang, Jizhe

    2014-09-01

    Direct conversion of raw biomass materials to fine chemicals is of great significance from both economic and ecological perspectives. In this paper, we report that a Keggin-type vanadium-substituted phosphomolybdic acid catalyst, namely H4PVMo11O40, is capable of converting various biomass-derived substrates to formic acid and acetic acid with high selectivity in a water medium and oxygen atmosphere. Under optimized reaction conditions, H4PVMo11O40 gave an exceptionally high yield of formic acid (67.8%) from cellulose, far exceeding the values achieved in previous catalytic systems. Our study demonstrates that heteropoly acids are generally effective catalysts for biomass conversion due to their strong acidities, whereas the composition of metal addenda atoms in the catalysts has crucial influence on the reaction pathway and the product selectivity. © 2013 Elsevier B.V.

  11. Introgression of High Yield Genes from Lycopersicon hirsutum acc. LA1777 Using CAPS Marker

    Institute of Scientific and Technical Information of China (English)

    LI Hong; WANG Xiao-xuan; SONG Ming; GAO Jian-chang; GUO Yan-mei; ZHU De-wei; DAI Shan-shu; DU Yong-chen

    2007-01-01

    The idea behind this study is to show that using high yield genes from a wild tomato can enrich tomato breeding resources and accelerate tomato breeding programs. In this study, the near-isogenic line TA1229 containing a 24-cM introgression at the bottom of chromosome 1 from Lycopersicon acc. LA1777, affects several higher yield traits. The TA1229 × 9706 BC1population was analyzed by marker-assisted selection and the traits of the population were evaluated. Twenty-three recombinant individuals that carried a shorter segment than TA1229 were obtained. Among them, 16 lines with the chromosome 1 recombinant segment can increase tomato yield and a QTL affecting yield was found between TG53 and TG158. Sixteen recombinant lines are useful to improve the tomato variety.

  12. Modeling Integrated High-Yield IFE Target Explosions in Xenon Filled Chambers

    Science.gov (United States)

    Fatenejad, Milad; Moses, Gregory

    2010-11-01

    We will present the results of several radiation-hydrodynamics simulations which model the aftermath of an exploding high yield (200 MJ) indirect drive target in a xenon filled reactor chamber. The goal is to determine the radial extent to which debris from the target and hohlraum expands into the target chamber. The 1D radiation-hydrodynamics code BUCKY is used to perform integrated simulations of the target explosion beginning from ignition and includes interactions between the chamber gas and tungsten first wall. The 3D radiation-hydrodynamics code Cooper will be used to model the growth of fluid instabilities as the target material expands into the xenon gas. Cooper will also be used to investigate the early-time interaction between the burning target and hohlraum shortly after ignition.

  13. Microbial electrolysis cells for high yield hydrogen gas production from organic matter.

    Science.gov (United States)

    Logan, Bruce E; Call, Douglas; Cheng, Shaoan; Hamelers, Hubertus V M; Sleutels, Tom H J A; Jeremiasse, Adriaan W; Rozendal, René A

    2008-12-01

    The use of electrochemically active bacteria to break down organic matter, combined with the addition of a small voltage (> 0.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield of hydrogen gas. While microbial electrolysis was invented only a few years ago, rapid developments have led to hydrogen yields approaching 100%, energy yields based on electrical energy input many times greater than that possible by water electrolysis, and increased gas production rates. MECs used to make hydrogen gas are similar in design to microbial fuel cells (MFCs) that produce electricity, but there are important differences in architecture and analytical methods used to evaluate performance. We review here the materials, architectures, performance, and energy efficiencies of these MEC systems that show promise as a method for renewable and sustainable energy production, and wastewater treatment.

  14. Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic Matter

    KAUST Repository

    Logan, Bruce E.

    2008-12-01

    The use of electrochemically active bacteria to break down organic matter, combined with the addition of a small voltage (>0.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield of hydrogen gas. While microbial electrolysis was invented only a few years ago, rapid developments have led to hydrogen yields approaching 100%, energy yields based on electrical energy input many times greater than that possible by water electrolysis, and increased gas production rates. MECs used to make hydrogen gas are similar in design to microbial fuel cells (MFCs) that produce electricity, but there are important differences in architecture and analytical methods used to evaluate performance. We review here the materials, architectures, performance, and energy efficiencies of these MEC systems that show promise as a method for renewable and sustainable energy production, and wastewater treatment. © 2008 American Chemical Society.

  15. Economics of fertility in high-yielding dairy cows on confined TMR systems.

    Science.gov (United States)

    Cabrera, V E

    2014-05-01

    The objective of this review paper was to summarise the latest findings in dairy cattle reproductive economics with an emphasis on high yielding, confined total mixed ration systems. The economic gain increases as the reproductive efficiency improves. These increments follow the law of diminishing returns, but are still positive even at high reproductive performance. Reproductive improvement results in higher milk productivity and, therefore, higher milk income over feed cost, more calf sales and lower culling and breeding expenses. Most high-yielding herds in the United States use a combination of timed artificial insemination (TAI) and oestrous detection (OD) reproductive programme. The ratio of achievable pregnancies between OD and TAI determines the economic value difference between both and their combinations. Nonetheless, complex interactions between reproductive programme, herd relative milk yield, and type of reproductive programme are reported. For example, higher herd relative milk yield would favour programme relying more on TAI. In addition, improved reproductive efficiency produces extra replacements. The availability of additional replacements could allow more aggressive culling policies (e.g. less services for non-pregnant cows) to balance on-farm supply and demand of replacements. Balancing heifer replacement availability in an efficient reproductive programme brings additional economic benefits. New technologies such as the use of earlier chemical tests for pregnancy diagnosis could be economically effective depending on the goals and characteristics of the farm. Opportunities for individual cow reproductive management within defined reproductive programme exist. These decisions would be based on economic metrics derived from the value of a cow such as the value of a new pregnancy, the cost of a pregnancy loss, or the cost of an extra day open.

  16. High yield polyol synthesis of round- and sharp-end silver nanowires with high aspect ratio

    Energy Technology Data Exchange (ETDEWEB)

    Nekahi, A.; Marashi, S.P.H., E-mail: pmarashi@aut.ac.ir; Fatmesari, D. Haghshenas

    2016-12-01

    Long silver nanowires (average length of 28 μm, average aspect ratio of 130) with uniform diameter along their length were produced by polyol synthesis of AgNO{sub 3} in ethylene glycol in the presence of PVP as preferential growth agent. Nanowires were produced with no addition of chloride salts such as NaCl or CuCl{sub 2} (or other additives such as Na{sub 2}S) which are usually used for lowering reduction rate of Ag ions by additional etchant of O{sub 2}/Cl{sup −}. Lower reduction rate was obtained by increasing the injection time of PVP and AgNO{sub 3} solutions, which was the significant factor in the formation of nanowires. Therefore, there was enough time for reduced Ag atoms to be deposited preferentially in the direction of PVP chains, resulting in high yield (the fraction of nanowires in the products) of nanowires (more than 95%) with high aspect ratio. The produced nanowires had both round- and sharp-ends with pentagonal cross section. Higher energy level of Ag atoms in borders of MTPs, which increases the dissolution rate of precipitated atoms, in addition to partial melting of MTPs at high synthesis temperatures, leads to the curving of the surfaces of exposed (111) crystalline planes in some MTPs and the formation of round-end silver nanowires. - Highlights: • Long silver nanowires with high aspect ratio of 130 were produced. • More than 95% nanowires were produced in products. • The produced nanowires had round- and sharp-ends with pentagonal cross section. • Additives were needed neither for high yield synthesis nor for round-end nanowires. • Melting and etching of MTPs in high energy borders resulted to round-end nanowires.

  17. CR Dhan 407, a high-yielding rice cultivar released for the rainfed shallow lowland ecosystem of eastern India

    National Research Council Canada - National Science Library

    Roy, P S; Patnaik, S S C; Patnaik, A; Rao, G J N; Singh, O N

    2015-01-01

    .... Development and release of CR Dhan 407, a high-yielding cultivar, with a potential yield of more than 5 tons per hectare and non-lodging plant type, can address the problem of yield stagnation...

  18. Neutron Repulsion

    OpenAIRE

    Manuel, Oliver K.

    2011-01-01

    Earth is connected gravitationally, magnetically and electrically to its heat source - a neutron star that is obscured from view by waste products in the photosphere. Neutron repulsion is like the hot filament in an incandescent light bulb. Excited neutrons are emitted from the solar core and decay into hydrogen that glows in the photosphere like a frosted light bulb. Neutron repulsion was recognized in nuclear rest mass data in 2000 as the overlooked source of energy, the keystone of an arch...

  19. Poly(dA:dT) tracts: major determinants of nucleosome organization.

    Science.gov (United States)

    Segal, Eran; Widom, Jonathan

    2009-02-01

    Homopolymeric stretches of deoxyadenosine nucleotides (A's) on one strand of double-stranded DNA, referred to as poly(dA:dT) tracts or A-tracts, are overabundant in eukaryotic genomes. They have unusual structural, dynamic, and mechanical properties, and may resist sharp bending. Such unusual material properties, together with their overabundance in eukaryotes, raised the possibility that poly(dA:dT) tracts might function in eukaryotes to influence the organization of nucleosomes at many genomic regions. Recent genome-wide studies strongly confirm these ideas and suggest that these tracts play major roles in chromatin organization and genome function. Here we review what is known about poly(dA:dT) tracts and how they work.

  20. Association between udder morphology and in vitro activity of milk leukocytes in high yielding crossbred cows

    Directory of Open Access Journals (Sweden)

    Tripti Sharma (Buragohain

    2017-03-01

    Full Text Available Aim: The present investigation was conducted to study the association between udder morphology and in vitro activity of milk leukocytes in high yielding crossbred cows. Materials and Methods: A total of 48 healthy high yielding crossbred cows were selected for the study. The udder configuration and teat/udder morphology were recorded before milking. Milk samples (100 ml/cow were collected aseptically. Milk somatic cell counts (SCC and milk differential leukocyte counts were performed microscopically. Milk leukocytes (viz., neutrophils, lymphocytes, and macrophages were isolated from milk samples by density gradient centrifugation. Phagocytic index (PI of milk neutrophils and macrophages were evaluated by colorimetric nitro blue tetrazolium assay. Lymphocytes proliferation response was estimated by MTT assay and expressed as stimulation index. Results: There was a significant (p<0.01 positive correlation between milk SCC with mid teat diameter, teat base diameter and significant (p<0.05 negative correlation between milk SCC and the height of the teat from the ground. Milk SCC was found to be significantly (p<0.01 lower in bowl-shaped udder and higher (p<0.01 in pendulous type. Milk macrophage percentage was positively (p<0.01 correlated with udder circumference. PI of milk neutrophil was negatively (p<0.01 correlation between teat base diameter, and PI of milk macrophages was found to be positively (p<0.01 correlated with teat apex diameter. Both PI of milk neutrophils and macrophages was found to be significantly (p<0.01 lower in the animals having flat and round teat and pendulous type of udder. In vitro PI of milk neutrophils was found to be significantly (p<0.01 lower in flat teat. In vitro PI of milk macrophages was found to be significantly (p<0.01 lower in the round and flat teats compared to pointed and cylindrical teats. Conclusion: Udder risk factors such as teat shape and size, teat to floor distance, udder shape, and size may decrease

  1. Development of High Yield Feedstocks and Biomass Conversion Technology for Renewable Energy

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Andrew G. [Univ. of Hawaii, Honolulu, HI (United States); Crow, Susan [Univ. of Hawaii, Honolulu, HI (United States); DeBeryshe, Barbara [Univ. of Hawaii, Honolulu, HI (United States); Ha, Richard [Hamakua Springs County Farms, Hilo, HI (United States); Jakeway, Lee [Hawaiian Commercial and Sugar Company, Puunene, HI (United States); Khanal, Samir [Univ. of Hawaii, Honolulu, HI (United States); Nakahata, Mae [Hawaiian Commercial and Sugar Company, Puunene, HI (United States); Ogoshi, Richard [Univ. of Hawaii, Honolulu, HI (United States); Shimizu, Erik [Univ. of Hawaii, Honolulu, HI (United States); Stern, Ivette [Univ. of Hawaii, Honolulu, HI (United States); Turano, Brian [Univ. of Hawaii, Honolulu, HI (United States); Turn, Scott [Univ. of Hawaii, Honolulu, HI (United States); Yanagida, John [Univ. of Hawaii, Honolulu, HI (United States)

    2015-04-09

    This project had two main goals. The first goal was to evaluate several high yielding tropical perennial grasses as feedstock for biofuel production, and to characterize the feedstock for compatible biofuel production systems. The second goal was to assess the integration of renewable energy systems for Hawaii. The project focused on high-yield grasses (napiergrass, energycane, sweet sorghum, and sugarcane). Field plots were established to evaluate the effects of elevation (30, 300 and 900 meters above sea level) and irrigation (50%, 75% and 100% of sugarcane plantation practice) on energy crop yields and input. The test plots were extensive monitored including: hydrologic studies to measure crop water use and losses through seepage and evapotranspiration; changes in soil carbon stock; greenhouse gas flux (CO2, CH4, and N2O) from the soil surface; and root morphology, biomass, and turnover. Results showed significant effects of environment on crop yields. In general, crop yields decrease as the elevation increased, being more pronounced for sweet sorghum and energycane than napiergrass. Also energy crop yields were higher with increased irrigation levels, being most pronounced with energycane and less so with sweet sorghum. Daylight length greatly affected sweet sorghum growth and yields. One of the energy crops (napiergrass) was harvested at different ages (2, 4, 6, and 8 months) to assess the changes in feedstock characteristics with age and potential to generate co-products. Although there was greater potential for co-products from younger feedstock, the increased production was not sufficient to offset the additional cost of harvesting multiple times per year. The feedstocks were also characterized to assess their compatibility with biochemical and thermochemical conversion processes. The project objectives are being continued through additional support from the Office of Naval Research, and the Biomass Research and Development

  2. Molecular signature of high yield (growth influenza a virus reassortants prepared as candidate vaccine seeds.

    Directory of Open Access Journals (Sweden)

    Manojkumar Ramanunninair

    Full Text Available BACKGROUND: Human influenza virus isolates generally grow poorly in embryonated chicken eggs. Hence, gene reassortment of influenza A wild type (wt viruses is performed with a highly egg adapted donor virus, A/Puerto Rico/8/1934 (PR8, to provide the high yield reassortant (HYR viral 'seeds' for vaccine production. HYR must contain the hemagglutinin (HA and neuraminidase (NA genes of wt virus and one to six 'internal' genes from PR8. Most studies of influenza wt and HYRs have focused on the HA gene. The main objective of this study is the identification of the molecular signature in all eight gene segments of influenza A HYR candidate vaccine seeds associated with high growth in ovo. METHODOLOGY: The genomes of 14 wt parental viruses, 23 HYRs (5 H1N1; 2, 1976 H1N1-SOIV; 2, 2009 H1N1pdm; 2 H2N2 and 12 H3N2 and PR8 were sequenced using the high-throughput sequencing pipeline with big dye terminator chemistry. RESULTS: Silent and coding mutations were found in all internal genes derived from PR8 with the exception of the M gene. The M gene derived from PR8 was invariant in all 23 HYRs underlining the critical role of PR8 M in high yield phenotype. None of the wt virus derived internal genes had any silent change(s except the PB1 gene in X-157. The highest number of recurrent silent and coding mutations was found in NS. With respect to the surface antigens, the majority of HYRs had coding mutations in HA; only 2 HYRs had coding mutations in NA. SIGNIFICANCE: In the era of application of reverse genetics to alter influenza A virus genomes, the mutations identified in the HYR gene segments associated with high growth in ovo may be of great practical benefit to modify PR8 and/or wt virus gene sequences for improved growth of vaccine 'seed' viruses.

  3. Single PA mutation as a high yield determinant of avian influenza vaccines

    Science.gov (United States)

    Lee, Ilseob; Il Kim, Jin; Park, Sehee; Bae, Joon-Yong; Yoo, Kirim; Yun, Soo-Hyeon; Lee, Joo-Yeon; Kim, Kisoon; Kang, Chun; Park, Man-Seong

    2017-01-01

    Human infection with an avian influenza virus persists. To prepare for a potential outbreak of avian influenza, we constructed a candidate vaccine virus (CVV) containing hemagglutinin (HA) and neuraminidase (NA) genes of a H5N1 virus and evaluated its antigenic stability after serial passaging in embryonated chicken eggs. The passaged CVV harbored the four amino acid mutations (R136K in PB2; E31K in PA; A172T in HA; and R80Q in M2) without changing its antigenicity, compared with the parental CVV. Notably, the passaged CVV exhibited much greater replication property both in eggs and in Madin-Darby canine kidney and Vero cells. Of the four mutations, the PA E31K showed the greatest effect on the replication property of reverse genetically-rescued viruses. In a further luciferase reporter, mini-replicon assay, the PA mutation appeared to affect the replication property by increasing viral polymerase activity. When applied to different avian influenza CVVs (H7N9 and H9N2 subtypes), the PA E31K mutation resulted in the increases of viral replication in the Vero cell again. Taken all together, our results suggest the PA E31K mutation as a single, substantial growth determinant of avian influenza CVVs and for the establishment of a high-yield avian influenza vaccine backbone. PMID:28084423

  4. Creation of High-Yield Polyhydroxyalkanoates Engineered Strains by Low Energy Ion Implantation

    Science.gov (United States)

    Qian, Shiquan; Cheng, Ying; Zhu, Suwen; Cheng, Beijiu

    2008-12-01

    Polyhydroxyalkanoates (PHAs), as a candidate for biodegradable plastic materials, can be synthesized by numerous microorganisms. However, as its production cost is high in comparison with those of chemically synthesized plastics, a lot of research has been focused on the efficient production of PHAs using different methods. In the present study, the mutation effects of PHAs production in strain pCB4 were investigated with implantation of low energy ions. It was found that under the implantation conditions of 7.8 × 1014 N+/cm2 at 10 keV, a high-yield PHAs strain with high genetic stability was generated from many mutants. After optimizing its fermentation conditions, the biomass, PHAs concentration and PHAs content of pCBH4 reached 2.26 g/L, 1.81 g/L, and 80.08% respectively, whereas its wild type controls were about 1.24 g/L, 0.61 g/L, and 49.20%. Moreover, the main constituent of PHAs was identified as poly-3-hydroxybutyrates (PHB) in the mutant stain and the yield of this compound was increased up to 41.33% in contrast to that of 27.78% in the wild type strain.

  5. Simple and high yield access to octafunctional azido, amine and urea group bearing cubic spherosilicates.

    Science.gov (United States)

    Schäfer, Sandra; Kickelbick, Guido

    2016-12-20

    Spherosilicates and polyhedral oligomeric silsesquioxanes represent unique well-defined rigid building blocks for molecular and hybrid materials. Drawbacks in their synthesis are often low yields and the restricted presence of functional groups either based on incomplete transformation of all corners or the reactivity of the functional groups. Particularly amine-functionalization reveals some synthetic challenges. In this study we report the synthesis of a new class of octafunctionalized hydrogen bond forming spherosilicates via a facile route based on octabromo alkyl functionalized cubic spherosilicates. Four different alkyl chain lengths, namely C4, C5, C6 and C11, were realized starting from ω-alkenylbromides via hydrosilylation of Q8M8(H). Using sodium azide in a mixture of acetonitrile : DMF = 10 : 1, the octaazide was obtained quantitatively and could be rapidly transformed in an octaamine cube via catalytic hydrogenation over Pd/C in absolute ethanol. The following reaction to hydrogen bond forming spherosilicates was performed in situ by adding propyl isocyanate. All transformations proceed quantitatively at the eight corners of the cube, which was evidenced by NMR spectroscopy and ESI-MS measurements. The Q8-target compound can be separated after each reaction step over simple chemical workup while no cage rearrangement was observed. The structures were confirmed using (1)H, (13)C, (29)Si-NMR, FT-IR, elemental analysis and ESI-MS. The method opens a high yield route (overall isolated yield 83-88%) for structural building blocks in hybrid materials.

  6. Epidemiology and impact of Fasciola hepatica exposure in high-yielding dairy herds.

    Science.gov (United States)

    Howell, Alison; Baylis, Matthew; Smith, Rob; Pinchbeck, Gina; Williams, Diana

    2015-09-01

    The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (phepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables.

  7. Nitrogen-doped carbon nanotubes with tunable structure and high yield produced by ultrasonic spray pyrolysis

    Science.gov (United States)

    Liu, Jian; Zhang, Yong; Ionescu, Mihnea Ioan; Li, Ruying; Sun, Xueliang

    2011-06-01

    Nitrogen-doped carbon nanotubes (CN x) were prepared by ultrasonic spray pyrolysis from mixtures of imidazole and acetonitrile. Imidazole, as an additive, was used to control the structure and nitrogen doping in CN x by adjusting its concentration in the mixtures. Scanning electron microscopy observation showed that the addition of imidazole increased the nanotube growth rate and yield, while decreased the nanotube diameter. Transmission electron microscopy study indicated that the addition of imidazole promoted the formation of a dense bamboo-like structure in CN x. X-ray photoelectron spectroscopy analysis demonstrated that the nitrogen content varied from 3.2 to 5.2 at.% in CN x obtained with different imidazole concentrations. Raman spectra study showed that the intensity ratio of D to G bands gradually increased, while that of 2D to G bands decreased, due to increasing imidazole concentration. The yield of CN x made from mixtures of imidazole and acetonitrile can reach 192 mg in 24 min, which is 15 times that of CN x prepared from only acetonitrile. The aligned CN x, with controlled nitrogen doping, tunable structure and high yield, may find applications in developing non-noble catalysts and novel catalyst supports for fuel cells.

  8. Nitrogen-doped carbon nanotubes with tunable structure and high yield produced by ultrasonic spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Liu Jian; Zhang Yong; Ionescu, Mihnea Ioan; Li Ruying [Department of Mechanical and Materials Engineering, University of Western Ontario, London, ON, N6A 5B9 (Canada); Sun Xueliang, E-mail: xsun@eng.uwo.ca [Department of Mechanical and Materials Engineering, University of Western Ontario, London, ON, N6A 5B9 (Canada)

    2011-06-15

    Nitrogen-doped carbon nanotubes (CN{sub x}) were prepared by ultrasonic spray pyrolysis from mixtures of imidazole and acetonitrile. Imidazole, as an additive, was used to control the structure and nitrogen doping in CN{sub x} by adjusting its concentration in the mixtures. Scanning electron microscopy observation showed that the addition of imidazole increased the nanotube growth rate and yield, while decreased the nanotube diameter. Transmission electron microscopy study indicated that the addition of imidazole promoted the formation of a dense bamboo-like structure in CN{sub x}. X-ray photoelectron spectroscopy analysis demonstrated that the nitrogen content varied from 3.2 to 5.2 at.% in CN{sub x} obtained with different imidazole concentrations. Raman spectra study showed that the intensity ratio of D to G bands gradually increased, while that of 2D to G bands decreased, due to increasing imidazole concentration. The yield of CN{sub x} made from mixtures of imidazole and acetonitrile can reach 192 mg in 24 min, which is 15 times that of CN{sub x} prepared from only acetonitrile. The aligned CN{sub x}, with controlled nitrogen doping, tunable structure and high yield, may find applications in developing non-noble catalysts and novel catalyst supports for fuel cells.

  9. Advances and Prospects in Breeding Japonica Rice for Super High Yield in the Northern China

    Institute of Scientific and Technical Information of China (English)

    CHEN Wen-fu; XU Zheng-jin; ZHANG Wen-zhong

    2007-01-01

    In this paper, advances and prospects in breeding japonica rice for super high yield in the northern China were analyzed comprehensively in terms of breeding theories, techniques and practices. The author holds that developing and spreading super rice is an important way to enhance the overall yielding ability of japonica rice and attaining immense expansion of rice production. After theories and technical guidelines for super rice breeding were formulated, which involved the creation of new plant morphology and strong hybrid vigor through crossing indica with japonica subspecies, the optimization of combination of desirable traits via multiple crossing or backcrossing, the assemblage of favorable genes and the integration of ideal plant morphology with the utilization of vigor-major breakthroughs have been made in conventional breeding of japonica super rice. A batch of new super rice varieties marked by superior rice quality and high disease resistance, such as Shennong 265, Shennong 606, and Jijing 88, etc., have been developed and released. In comparison with the advancement in conventional breeding of super rice, progress in hybrid japonica super rice breeding is slower because of climatic and ecological constraint in northern China. Therefore, solving the contradictions between vigor and growth duration, between yield and rice quality, and boosting vastly seed production are still serious challenges for breeders of hybrid japonica rice. Physiological and genetic problems in japonica super rice breeding are also discussed in this paper.

  10. A novel high yield method for dry functionalization of carbon nanotubes.

    Science.gov (United States)

    Ansari, S G

    2011-04-01

    A novel and high yield (> 80%) dry method to functionalize (dry functionalization) carbon nanotubes (CNTs) using hydrothermal method, is reported here. The hydrothermal solution was prepared with HNO3, H2SO4 and H2O2 (1:3:2 vol. ratios) and reaction was carried out from 120 to 200 degrees C for 24 h. CNTs (multi wall) were kept in a way to avoid the direct contact with the solution. Treatment above 180 degrees C resulted in better functionalization of nanotubes as observed from Fourier transform infrared absorption spectroscopic (FTIR) measurements. Field emission scanning electron microscopic (FESEM) images showed that after functionalization, the nanotubes are seen with open ends, granular surface, twisted and are joined together. These clearly indicate the destruction of the graphite structure on the surface. This indicates that after treatment, CNTs reactivity has increased at the ends as well as at the side walls. X-ray Photoelectron Spectroscopic (XPS) studies show a shift in the C 1s peak position, increase in O 1s peak intensity and appearance of an N 1s peak.

  11. Engineering a high-yield glutathione strain of Hansenula polymorpha using ion beam implantation.

    Science.gov (United States)

    Qian, Weidong; Fu, Yunfang; Cai, Changlong

    2013-01-01

    To generate an industrial strain of Hansenula polymorpha capable of yielding greater levels of glutathione (GSH), wild strain H. polymorpha DL-1 cells were mutated using a nitrogen ion beam, a novel mutagen. At an energy level of 20 keV and dose of 2.13 × 10(16) ions/cm(2), H. polymorpha strain 28 (HP28) with a high-yield of GSH was screened. HP28 intracellular GSH levels reached 337.16 mg/L by ion beam implantation, 1.56 times greater than that of the wild type strain when the fermentation time was shortened from 48 hr to 42 hr, greatly improving efficiency and reducing the cost of industrial-scale production. The enhanced efficiency of HP28 is promising for GSH production from lignocellulosic materials. Therefore, the ion beam implantation would be a cost-effective alternative to the conventional mutation method for engineering yeast and improving its utility.

  12. High yield expression of catalytically active USP18 (UBP43 using a Trigger Factor fusion system

    Directory of Open Access Journals (Sweden)

    Basters Anja

    2012-08-01

    Full Text Available Abstract Background Covalent linkage of the ubiquitin-like protein ISG15 interferes with viral infection and USP18 is the major protease which specifically removes ISG15 from target proteins. Thus, boosting ISG15 modification by protease inhibition of USP18 might represent a new strategy to interfere with viral replication. However, so far no heterologous expression system was available to yield sufficient amounts of catalytically active protein for high-throughput based inhibitor screens. Results High-level heterologous expression of USP18 was achieved by applying a chaperone-based fusion system in E. coli. Pure protein was obtained in a single-step on IMAC via a His6-tag. The USP18 fusion protein exhibited enzymatic activity towards cell derived ISG15 conjugated substrates and efficiently hydrolyzed ISG15-AMC. Specificity towards ISG15 was shown by covalent adduct formation with ISG15 vinyl sulfone but not with ubiquitin vinyl sulfone. Conclusion The results presented here show that a chaperone fusion system can provide high yields of proteins that are difficult to express. The USP18 protein obtained here is suited to setup high-throughput small molecule inhibitor screens and forms the basis for detailed biochemical and structural characterization.

  13. Research Advances in High-Yielding Cultivation and Physiology of Super Rice

    Institute of Scientific and Technical Information of China (English)

    FU Jing; YANG Jian-chang

    2012-01-01

    In 1996,China launched a program to breed super rice or super hybrid rice by combining intersubspecific heterosis with ideal plant types.Today,approximately 80 super rice varieties have been released and some of them show high grain yields of 12-21 t/hm2 in field experiments.The main reasons for the high yields of super rice varieties,compared with those of conventional varieties,can be summarized as follows:more spikelets per panicle and larger sink size (number of spikelets per square meter); larger leaf area index,longer duration of green leaf,greater photosynthetic rate,higher lodging resistance,greater dry matter accumulation before the heading stage,greater remobilization of pre-stored carbohydrates from stems and leaves to grains during the grain-filling period; and larger root system and greater root activity.However,there are two main problems in super rice production:poor grain-filling of the later-flowering inferior spikelets (in contrast to earlier-flowering superior spikelets),and low and unstable seed-setting rate.Here,we review recent research advances in the crop physiology of super rice,focusing on biological features,formation of yield components,and population quality.Finally,we suggest further research on crop physiology of super rice.

  14. Creation of High-Yield Polyhydroxyalkanoates Engineered Strains by Low Energy Ion Implantation

    Institute of Scientific and Technical Information of China (English)

    QIAN Shiquan; CHENG Ying; ZHU Suwen; CHENG Beijiu

    2008-01-01

    Polyhydroxyalkanoates (PHAs), as a candidate for biodegradable plastic materials, can be synthesized by numerous microorganisms. However, as its production cost is high in comparison with those of chemically synthesized plastics, a lot of research has been focused on the efficient production of PHAs using different methods. In the present study, the mutation effects of PHAs production in strain pCB4 were investigated with implantation of low energy ions. It was found that under the implantation conditions of 7.8×1014 N+/cm2 at 10 keV, a high-yield PHAs strain with high genetic stability was generated from many mutants. After optimizing its fermentation conditions, the biomass, PHAs concentration and PHAs content of pCBH4reached 2.26 g/L, 1.81 g/L, and 80.08% respectively, whereas its wild type controls were about 1.24 g/L, 0.61 g/L, and 49.20%. Moreover, the main constituent of PHAs was identified as poly-3-hydroxybutyrates (PHB) in the mutant stain and the yield of this compound was increased up to 41.33% in contrast to that of 27.78% in the wild type strain.

  15. Analysis of Some Egyptian Cosmetic Samples by Fast Neutron Activation Analysis

    CERN Document Server

    Medhat, M E; Fayez-Hassan, M

    2001-01-01

    A description of D-T neutron generator (NG) is presented. This generator can be used for fast neutron activation analysis applied to determine some selected elements, especially light elements, in different materials. In our work, the concentration of the elements Na, Mg, Al, Si, K, Cl, Ca and Fe, were determined in two domestic brands of face powder by using 14 MeV neutron activation analysis.

  16. Fusion performances and alpha heating in future JET D-T plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Balet, B.; Cordey, J.G.; Gibson, A.; Lomas, P.; Stubberfield, P.M.; Thomas, P. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-07-01

    The new pump divertor installed at JET should allow high performance pulses of a few seconds duration by both preventing the impurity influx and controlling the density evolution. The TRANSP code has been used in a predictive mode to assess the possible fusion performance of such plasmas fuelled with a 50:50 mixture of D and T, and the effect of alpha particles heating on Te and Ti. Several cases are considered: 50:50 D-T mix; 50:50 D-T mix, no C bloom; 50:50 D-T mix, VH phase, density control; 50:50 D-T mix, VH phase, density control, 6 Ma. The predictions show that if the the bloom and MHD instabilities can be controlled at higher plasma currents using a higher toroidal field to keep a reasonable beta value, then a higher fusion performance steady state plasma with Q{sub DT} superior to 2.5 should be possible. The alpha heating power of 4.9 MW would lead to a 74% increase in Te. 4 refs., 4 figs., 1 tab.

  17. Investigating D-T Reaction Spectra with the Gas Cherenkov Detector

    Science.gov (United States)

    Huff, Michael A.; Kim, Yong Ho; McEvoy, Aaron; Young, Carlton S.; Mack, Joe M.; Herrmann, Hans W.; Horsfield, Colin J.

    2010-11-01

    In this study, a new analysis of the gamma ray spectra of the D-T fusion reaction using a Gas Cherenkov Detector (GCD) is presented. The D-T reaction is an essential process to understand for the future of fusion science. The reaction produces a He^5* nucleus that usually decays into a He^4 + n. It has been seen that this reaction produces a 16.75 MeV gamma ray .0025% of the time. The Gamma Ray History (GRH) group at Los Alamos proposes that there is an even less often occurrence where a gamma ray of around 12 MeV is produced. As the truth of this statement would affect the future potential yield of fusion reactors using D-T fuel, it is worth investigating. D-T spectra were obtained by detecting the produced gamma ray with the GCD at the University of Rochester OMEGA laser facility. A GCD response curve, calculated by the Monte Carlo modeling software ACCEPT, was used to forward convolve theoretical spectra into what the theoretical curves would have looked like in the GCD data. Results are presented.

  18. DCE-PWI 3D T1-measurement as function of time or flip angle

    DEFF Research Database (Denmark)

    Mikkelsen, Irene Klærke; Peters, David Alberg; Tietze, Anna

    Dynamic Contrast Enhanced Perfusion Weighted Imaging (DCE-PWI) and the preceding T1 measurement is usually performed with a FLASH sequence. For the sake of speed, the 3D T1 measurement is often performed by measuring the signal for a range of flip angles instead of as a function the inversion (or...

  19. [Characteristics of canopy structure of super high yielding japonica hybrid rice community].

    Science.gov (United States)

    Chen, Jinhong; Zhang, Guoping; Guo, Hengde; Mao, Guojuan

    2003-06-01

    In this paper, the characteristics of canopy structure, such as the numbers of seedling, panicle and grain, the distribution of dry matters in different canopy layers and different organs, and the distributions of LAI and of solar radiation in different canopy layers of super high yielding community of japonica hybrid rice were studied, in comparison with normal japonica rice. The results showed that the total the dry matter weight and the dry matter weight of layers below 40 cm, 40-60 cm, 60-80 cm and above 80 cm of japonica hybrid rice canopy were 32.29%, 29.12%, 13.95%, 16.45% and 100.17% higher those that of normal japonica rice, respectively. The ratios of dry leaf (photosynthetic organ) and of dry panicle (sink organ) weight to total dry weight were 24.8% and 12.8%, respectively, which were greater than those of normal japonica rice, while the ratios of dry sheath and stem (storage organs) weight were 33.6% and 28.9%, respectively, which were lower than those of normal japonica rice. The allotment of LAI in different layers of japonica hybrid rice canopy was reasonable, and the LAI of above 40 cm layer at full heading stage reached 5.44. The solar radiation was well-distributed inside japonica hybrid rice canopy, for example, the solar radiation in layers below 60 cm were 13.1%-37.0% higher, but 5.9%-12.2% lower above 60 cm than that of normal japonica rice. The extinction coefficients of solar radiation in layers below 20 cm, 20-40 cm, 40-60 cm and 60-80 cm of japonica hybrid rice canopy were 35.1%, 13.5%, 29.1% and 17.2% lower than that of normal japonica rice, respectively.

  20. Photoyellowing inhibition of bleached high yield pulps using novel water-soluble UV screens.

    Science.gov (United States)

    Argyropoulos, D S; Halevy, P; Peng, P

    2000-02-01

    To address the deficiencies of benzophenone UV screens for preventing brightness reversion in high yield mechanical papers, we synthesized a new series of such materials with enhanced water solubility and compatibility with the lignocellulosic substrate. A series of 2,4-dihydroxybenzophenones (DHB) were synthesized containing various Mannich bases at the C3 position of one of its rings. They possess the UV-screening ability of o-hydroxylbenzophenones, and they also contain tertiary nitrogen atoms that may function as radical scavengers. Aqueous solutions of the hydrochloride salt of 3-(dimethylaminomethylene)-2,4-dihydroxylbenzophenone (1), when applied on bleached chemithermomechanical pulp (CTMP) sheets, were significantly more efficient in preventing photoyellowing than the original DHB applied on the sheets from ethanol-water solutions. This confirmed our original hypothesis that increasing the compatibility of the UV screen with the lignocellulosic matrix would increase its efficiency in preventing photoyellowing. Compound 1, however, was found to be somewhat more effective than its hydrochloride salt toward preventing photoyellowing. This was attributed to the synergistic action of the free tertiary aminic center attached on the molecule with its UV-screening ability. To comprehend further the various parameters that influence the photoyellowing inhibition performance of these compounds and DHB with bleached CTMP pulp fibers, a series of handsheets were prepared at different pH. The interactions of the protonated compound 1 with pulp fibers were then evaluated by studying their kinetics of absorption and desorption to and from the fiber matrix. This part of our study found that the adsorption of protonated Mannich derivatives of DHB onto pulp is most likely governed by a cation-exchange mechanism involving the cationic amine group with the sulfonic and carboxylic acid groups located on the surface of the fibers. The pH the paper sheet was made from was also

  1. A high-yield double-purification proteomics strategy for the identification of SUMO sites.

    Science.gov (United States)

    Hendriks, Ivo A; Vertegaal, Alfred C O

    2016-09-01

    The small ubiquitin-like modifier (SUMO) is a protein modifier that is post-translationally coupled to thousands of lysines in more than a thousand proteins. An understanding of which lysines are modified by SUMO is critical in unraveling its function as a master regulator of all nuclear processes, as well as its involvement in diseases such as cancer. Here we describe a protocol for the lysine-deficient (K0) method for efficient identification of SUMOylated lysines by mass spectrometry (MS). To our knowledge, the K0 method is the only currently available method that can routinely identify >1,000 SUMO sites in mammalian cells under standard growth conditions. The K0 strategy relies on introducing a His10-tagged SUMO wherein all lysines have been substituted to arginines. Lysine deficiency renders the SUMO immune to digestion by the endoproteinase Lys-C, which in turn allows for stringent and high-yield tandem purification through the His10 tag. In addition, the His10-tagged SUMO also contains a C-terminal Q87R mutation, which accommodates generation of SUMO-site peptides with a QQTGG mass remnant after digestion with trypsin. This remnant possesses a unique mass signature and readily generates diagnostic ions in the fragment ion scans, which increases SUMO-site identification confidence. The K0 method can be applied in any mammalian cell line or in any model system that allows for integration of the K0-SUMO construct. From the moment of cell lysis, the K0 method takes ∼7 d to perform.

  2. Optimization of Escherichia coli cultivation methods for high yield neuropeptide Y receptor type 2 production.

    Science.gov (United States)

    Berger, Christian; Montag, Cindy; Berndt, Sandra; Huster, Daniel

    2011-03-01

    The recombinant expression of human G protein-coupled receptors usually yields low production levels using commonly available cultivation protocols. Here, we describe the development of a high yield production protocol for the human neuropeptide Y receptor type 2 (Y2R), which provides the determination of expression levels in a time, media composition, and process parameter dependent manner. Protein was produced by Escherichia coli in a defined medium composition suitable for isotopic labeling required for investigations by nuclear magnetic resonance spectroscopy. The Y2 receptor was fused to a C-terminal 8x histidine tag by means of the pET vector system for easy one-step purification via affinity chromatography, yielding a purity of 95-99% for every condition tested, which was determined by SDS-PAGE and Western blot analysis. The Y2 receptor was expressed as inclusion body aggregates in complex media and minimal media, using different carbon sources. We investigated the influences of media composition, temperature, pH, and set specific growth rate on cell behavior, biomass wet weight specific and culture volume specific amounts of the target protein, which had been identified by inclusion body preparation, solubilization, followed by purification and spectrometric determination of the protein concentration. The developed process control strategy led to very high reproducibility of cell growth and protein concentrations with a maximum yield of 800 μg purified Y2 receptor per gram wet biomass when glycerol was used as carbon source in the mineral salt medium composition (at 38 °C, pH 7.0, and a set specific growth rate of 0.14 g/(gh)). The maximum biomass specific amount of purified Y2 receptor enabled the production of 35 mg Y2R per liter culture medium at an optical density (600 nm) of 25.

  3. High-yield synthesis of conductive carbon nanotube tips for multiprobe scanning tunneling microscope.

    Science.gov (United States)

    Konishi, H; Murata, Y; Wongwiriyapan, W; Kishida, M; Tomita, K; Motoyoshi, K; Honda, S; Katayama, M; Yoshimoto, S; Kubo, K; Hobara, R; Matsuda, I; Hasegawa, S; Yoshimura, M; Lee, J-G; Mori, H

    2007-01-01

    We have established a fabrication process for conductive carbon nanotube (CNT) tips for multiprobe scanning tunneling microscope (STM) with high yield. This was achieved, first, by attaching a CNT at the apex of a supporting W tip by a dielectrophoresis method, second, by reinforcing the adhesion between the CNT and the W tip by electron beam deposition of hydrocarbon and subsequent heating, and finally by wholly coating it with a thin metal layer by pulsed laser deposition. More than 90% of the CNT tips survived after long-distance transportation in air, indicating the practical durability of the CNT tips. The shape of the CNT tip did not change even after making contact with another metal tip more than 100 times repeatedly, which evidenced its mechanical robustness. We exploited the CNT tips for the electronic transport measurement by a four-terminal method in a multiprobe STM, in which the PtIr-coated CNT portion of the tip exhibited diffusive transport with a low resistivity of 1.8 kOmega/microm. The contact resistance at the junction between the CNT and the supporting W tip was estimated to be less than 0.7 kOmega. We confirmed that the PtIr thin layer remained at the CNT-W junction portion after excess current passed through, although the PtIr layer was peeled off on the CNT to aggregate into particles, which was likely due to electromigration or a thermally activated diffusion process. These results indicate that the CNT tips fabricated by our recipe possess high reliability and reproducibility sufficient for multiprobe STM measurements.

  4. Metabolic engineering of a thermophilic bacterium to produce ethanol at high yield.

    Science.gov (United States)

    Shaw, A Joe; Podkaminer, Kara K; Desai, Sunil G; Bardsley, John S; Rogers, Stephen R; Thorne, Philip G; Hogsett, David A; Lynd, Lee R

    2008-09-16

    We report engineering Thermoanaerobacterium saccharolyticum, a thermophilic anaerobic bacterium that ferments xylan and biomass-derived sugars, to produce ethanol at high yield. Knockout of genes involved in organic acid formation (acetate kinase, phosphate acetyltransferase, and L-lactate dehydrogenase) resulted in a strain able to produce ethanol as the only detectable organic product and substantial changes in electron flow relative to the wild type. Ethanol formation in the engineered strain (ALK2) utilizes pyruvate:ferredoxin oxidoreductase with electrons transferred from ferredoxin to NAD(P), a pathway different from that in previously described microbes with a homoethanol fermentation. The homoethanologenic phenotype was stable for >150 generations in continuous culture. The growth rate of strain ALK2 was similar to the wild-type strain, with a reduction in cell yield proportional to the decreased ATP availability resulting from acetate kinase inactivation. Glucose and xylose are co-utilized and utilization of mannose and arabinose commences before glucose and xylose are exhausted. Using strain ALK2 in simultaneous hydrolysis and fermentation experiments at 50 degrees C allows a 2.5-fold reduction in cellulase loading compared with using Saccharomyces cerevisiae at 37 degrees C. The maximum ethanol titer produced by strain ALK2, 37 g/liter, is the highest reported thus far for a thermophilic anaerobe, although further improvements are desired and likely possible. Our results extend the frontier of metabolic engineering in thermophilic hosts, have the potential to significantly lower the cost of cellulosic ethanol production, and support the feasibility of further cost reductions through engineering a diversity of host organisms.

  5. High yield simultaneous hydrogen and ethanol production under extreme-thermophilic (70 C) mixed culture environment

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chenxi [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); Department of Environmental Engineering, Technical University of Denmark, DK-2800, Kgs Lyngby (Denmark); O-Thong, Sompong [Department of Biology, Faculty of Science, Thaksin University, Patthalung 93110 (Thailand); Karakashev, Dimitar; Angelidaki, Irini [Department of Environmental Engineering, Technical University of Denmark, DK-2800, Kgs Lyngby (Denmark); Lu, Wenjing; Wang, Hongtao [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2009-07-15

    The effect of pH and medium composition on extreme-thermophilic (70 C) dark fermentative simultaneous hydrogen and ethanol production (process performance and microbial ecology) was investigated. Hydrogen and ethanol yields were optimized with respect to glucose, peptone, FeSO{sub 4}, NaHCO{sub 3}, yeast extract, trace mineral salts, vitamins, and phosphate buffer concentrations as well as initial pH as independent variables. A combination of low levels of both glucose ({<=}2 g/L) and vitamin solutions ({<=}1 mL/L) and high levels of initial pH ({>=}7), mineral salts solution ({>=}5 mL/L) and FeSO{sub 4} ({>=}100 mg/L) stimulated the hydrogen production, while high level of glucose ({>=}5 g/L) and low levels of both initial pH ({<=}5.5) and mineral salts solution ({<=}1 mL/L) enhanced the ethanol production. High yield of simultaneous hydrogen and ethanol production (1.58 mol H{sub 2}/mol glucose combined with an ethanol yield of 0.90 mol ethanol/mol glucose) was achieved under extreme-thermophilic mixed culture environment. Results obtained showed that the shift of the metabolic pathways favouring either hydrogen or ethanol production was affected by the change in cultivation conditions (pH and medium composition). The mixed culture in this study demonstrated flexible ability for simultaneous hydrogen and ethanol production, depending on pH and nutrients formulation. The microorganisms involved could be regarded as simultaneous hydrogen/ethanol producers, as hydrogen and ethanol fermentation under all conditions was carried out by a group of extreme-thermophilic bacterial species related to Thermoanaerobacter, Thermoanaerobacterium and Caldanaerobacter. (author)

  6. Neutron Radiography

    Science.gov (United States)

    Heller, A. K.; Brenizer, J. S.

    Neutron radiography and its related two-dimensional (2D) neutron imaging techniques have been established as invaluable nondestructive inspection methods and quantitative measurement tools. They have been used in a wide variety of applications ranging from inspection of aircraft engine turbine blades to study of two-phase fluid flow in operating proton exchange membrane fuel cells. Neutron radiography is similar to X-ray radiography in that the method produces a 2D attenuation map of neutron radiation that has penetrated the object being examined. However, the images produced differ and are often complementary due to the differences between X-ray and neutron interaction mechanisms. The uses and types of 2D neutron imaging have expanded over the past 15 years as a result of advances in imaging technology and improvements in neutron generators/sources and computers. Still, high-intensity sources such as those from reactors and spallation neutron sources, together with conventional film radiography, remain the mainstay of high-resolution, large field-of-view neutron imaging. This chapter presents a summary of the history, methods, and related variations of neutron radiography techniques.

  7. High-yield synthesis of few-layer graphene flakes through electrochemical expansion of graphite in propylene carbonate electrolyte.

    Science.gov (United States)

    Wang, Junzhong; Manga, Kiran Kumar; Bao, Qiaoliang; Loh, Kian Ping

    2011-06-15

    High-yield production of few-layer graphene flakes from graphite is important for the scalable synthesis and industrial application of graphene. However, high-yield exfoliation of graphite to form graphene sheets without using any oxidation process or super-strong acid is challenging. Here we demonstrate a solution route inspired by the lithium rechargeable battery for the high-yield (>70%) exfoliation of graphite into highly conductive few-layer graphene flakes (average thickness electrolyte of Li salts and organic solvents under high current density and exfoliated efficiently into few-layer graphene sheets with the aid of sonication. The dispersible graphene can be ink-brushed to form highly conformal coatings of conductive films (15 ohm/square at a graphene loading of <1 mg/cm(2)) on commercial paper.

  8. Fusion neutronics

    CERN Document Server

    Wu, Yican

    2017-01-01

    This book provides a systematic and comprehensive introduction to fusion neutronics, covering all key topics from the fundamental theories and methodologies, as well as a wide range of fusion system designs and experiments. It is the first-ever book focusing on the subject of fusion neutronics research. Compared with other nuclear devices such as fission reactors and accelerators, fusion systems are normally characterized by their complex geometry and nuclear physics, which entail new challenges for neutronics such as complicated modeling, deep penetration, low simulation efficiency, multi-physics coupling, etc. The book focuses on the neutronics characteristics of fusion systems and introduces a series of theories and methodologies that were developed to address the challenges of fusion neutronics, and which have since been widely applied all over the world. Further, it introduces readers to neutronics design’s unique principles and procedures, experimental methodologies and technologies for fusion systems...

  9. Induction of embryogenic callus and plantlet regeneration from young leaves of high yielding mature oil palm

    Directory of Open Access Journals (Sweden)

    Yeedum, I.

    2004-09-01

    Full Text Available Callus induction and plantlet regeneration from young leaves of high-yielding mature oil palm were carried out using 10-year and 20-year-old trees from Thepa Research Station, Faculty of Natural Resources,Prince of Songkla University, Hat Yai, and Trang Agricultural College, respectively. Culture media used in this experiment were Murashige and Skoog (1962 and Oil Palm supplemented with various concentrations of α-naphthaleneacetic acid (NAA or 2,4- dichlorophenoxy acetic acid (2,4-D or dicamba (Di and antioxidants.Young leaves from 6th to 11st frond were excised, sterilized, cut into 5x5 mm pieces and cultured in the dark at 26±4ºC or 28±0.5ºC for 3 months. The results revealed that MS medium with 200 mg/l ascorbic acid (As and 1 mg/l Di (MS-AsDi gave the highest callus induction percentage (7.93 after culture for 3 months at 28±0.5ºC. Leaf segments from 6th - 8th frond yielded callus forming percentage at 10% (averaged from 1, 2.5 and 5 mg/l Di containing MS medium. Ascorbic acid as an antioxidant at concentration of 200 mg/l supplemented in MS medium in the presence of 2.5 mg/l Di produced the highest callus induction percentage (11.2 and number of nodules (7.06. A high percentage of embryogenic callus formation (66.67 was obtained when the calli were transferred to the same medium component supplemented with 0.5 mg/l Di and 1,000 mg/l casein hydrolysate (CH (MS-AsDiCH. Haustorial-staged embryos were observed to be isolated as an individual embryo and germinated on MS medium without plant growth regulator (MS-free. Development of root could be classified into two distinct types, fibrous and tap root.

  10. Innovations in papermaking: an LCA of printing and writing paper from conventional and high yield pulp.

    Science.gov (United States)

    Manda, B M Krishna; Blok, Kornelis; Patel, Martin K

    2012-11-15

    Pulp and paper industry is facing challenges such as resource scarcity and greenhouse gas (GHG) emissions. The objective of this research is to investigate whether the use of new coatings (micro or nano TiO(2)) and different pulp types could bring savings in wood, energy, GHG emissions and other environmental impacts in comparison with conventional printing and writing paper. We studied three types of pulp, namely i) unbleached virgin kraft pulp, ii) recovered fiber, and iii) high yield virgin chemithermo-mechanical pulp (CTMP). A life cycle assessment (LCA) was conducted from cradle to grave. Applying attributional modeling, we found that wood savings amount to 60% for the nanoparticle coated recovered fiber paper and 35% for the micro TiO(2) coated CTMP paper. According to the ReCiPe single score impact assessment method, the new product configurations allow the reduction of the environmental impacts by 10-35% compared to conventional kraft paper. Applying consequential modeling, we found larger energy and GHG emission savings compared to attributional modeling because the saved wood is used for producing energy, thereby replacing fossil fuels. The nanoparticle coated recovered fiber paper offered savings of non-renewable energy use (NREU) by 100% (13GJ/ton paper) and GHG emission reduction by 75% (0.6 tonCO(2)eq./ton paper). Micro TiO(2) coated CTMP paper offered NREU savings by 25% (3GJ/ton paper) and savings of GHG emissions by 10% (0.1 tonCO(2)eq./ton paper). The taking into account of all environmental impacts with the ReCiPe single score method leads to comparable results as that of attributional modeling. We conclude that the nanoparticle coated recovered fiber paper offered the highest savings and lowest environmental impacts. However, human toxicity and ecotoxicity impacts of the nanoparticles were not included in this analysis and need further research. If this leads to the conclusion that the toxicity impacts of the nanoparticles are serious, then the

  11. EXTREME METEOROLOGICAL CONDITIONS AND METABOLIC PROFILE IN HIGH YIELDING HOLSTEINFRIESIAN DAIRY COWS

    Directory of Open Access Journals (Sweden)

    Z. GERGÁCZ

    2013-12-01

    Full Text Available The impact of two years (2002 and 2003 with different summer temperature extremes on variation in metabolic profile was analyzed in blood and urine samples taken from healthy, primiparous (n = 371 and multiparous (n = 795 high yielding Holstein-Friesian dairy cows. In this study main focus was lead on three most critical physiological phases, thus cows were assigned into three groups as follows: (1 dry cows for 10 days prior to calving; (2 cows 1-30 days after delivery, and (3 cows with more than 31 days post partum. Findings reveal clear response of the cows to heat in selected blood (hemoglobin, plasma aceto-acetic-acid, FFA, AST, glucose, urea and urine (pH, NABE and urea parameters. In the majority of cows, glucose and hemoglobin level, one of the most significant blood parameters, indicated symptoms of insufficient energy supply. Further metabolic indicators differed more or less from reference values depending on actual condition. Due to heat load dry matter intake has been decreased even by 10-15 per cent in primiparous cows. They were expected to increase body weight and size and simultaneously produce attain at large milk yields. In doing so that cows would have require large amount of nutrients. Out of parameters such as hemoglobin, glucose, FFA, AST and blood-urea differed from the reference values in most cases; however, this phenomenon seemed to be present in almost every case for hemoglobin and glucose. The lack of energy caused by heat stress can be contributed to the decrease of dry matter intake which has been indicated by the urea levels and pH both in blood and urine prevailing unfavorable and insufficient feeding practice. The results reconfirm the need to reconsider both the actual feeding practice (e.g. to increase of nutrient content in rations, reduce the intake of soluble proteins in rumen, pay attention of crude fiber in Total Mixed Rations (TMR, NDF and ADF, avoid overfeeding of inorganic buffers, to control moisture

  12. Innovations in papermaking: An LCA of printing and writing paper from conventional and high yield pulp

    Energy Technology Data Exchange (ETDEWEB)

    Manda, B.M. Krishna, E-mail: b.m.k.manda@uu.nl; Blok, Kornelis, E-mail: K.Blok@uu.nl; Patel, Martin K., E-mail: m.k.patel@uu.nl

    2012-11-15

    Pulp and paper industry is facing challenges such as resource scarcity and greenhouse gas (GHG) emissions. The objective of this research is to investigate whether the use of new coatings (micro or nano TiO{sub 2}) and different pulp types could bring savings in wood, energy, GHG emissions and other environmental impacts in comparison with conventional printing and writing paper. We studied three types of pulp, namely i) unbleached virgin kraft pulp, ii) recovered fiber, and iii) high yield virgin chemithermo-mechanical pulp (CTMP). A life cycle assessment (LCA) was conducted from cradle to grave. Applying attributional modeling, we found that wood savings amount to 60% for the nanoparticle coated recovered fiber paper and 35% for the micro TiO{sub 2} coated CTMP paper. According to the ReCiPe single score impact assessment method, the new product configurations allow the reduction of the environmental impacts by 10-35% compared to conventional kraft paper. Applying consequential modeling, we found larger energy and GHG emission savings compared to attributional modeling because the saved wood is used for producing energy, thereby replacing fossil fuels. The nanoparticle coated recovered fiber paper offered savings of non-renewable energy use (NREU) by 100% (13 GJ/ton paper) and GHG emission reduction by 75% (0.6 ton CO{sub 2} eq./ton paper). Micro TiO{sub 2} coated CTMP paper offered NREU savings by 25% (3 GJ/ton paper) and savings of GHG emissions by 10% (0.1 ton CO{sub 2} eq./ton paper). The taking into account of all environmental impacts with the ReCiPe single score method leads to comparable results as that of attributional modeling. We conclude that the nanoparticle coated recovered fiber paper offered the highest savings and lowest environmental impacts. However, human toxicity and ecotoxicity impacts of the nanoparticles were not included in this analysis and need further research. If this leads to the conclusion that the toxicity impacts of the

  13. Neutron Albedo

    CERN Document Server

    Ignatovich, V K

    2005-01-01

    A new, algebraic, method is applied to calculation of neutron albedo from substance to check the claim that use of ultradispersive fuel and moderator of an active core can help to gain in size and mass of the reactor. In a model of isotropic distribution of incident and reflected neutrons it is shown that coherent scattering on separate grains in the case of thermal neutrons increases transport cross section negligibly, however it decreases albedo from a wall of finite thickness because of decrease of substance density. A visible increase of albedo takes place only for neutrons with wave length of the order of the size of a single grain.

  14. Understanding scaling of ignition metrics for high-yield implosions on the NIF

    Science.gov (United States)

    Springer, Paul; Hurricane, Omar; Hammer, J. H.; Callahan, D. A.; Casey, D. T.; Cerjan, C. J.; Edwards, M. J.; Field, J. E.; Gaffney, J.; Grim, G. P.; Kritcher, A. L.; Ma, T.; Macphee, A. G.; Munro, D. H.; Nora, R. C.; Patel, P. K.; Peterson, L.; Spears, B.

    2016-10-01

    The self-heating condition for an imploding hotspot requires understanding the balance between mechanical work, heating via fusion reactions, and the radiative and conduction losses. A 3D cognizant Lawson ignition threshold metric is derived based on net fusion hotspot heating achieved when hotspot rho-r and ion temperature exceed critical values that depend on the temperature-dependent loss mechanisms. Key to understanding and scaling such analysis is an accurate determination of hotspot density and pressure, which are generally inferred using the yield, the thermal temperature, and other experimental data. 3D flow and its effect on neutron spectra can lead to overestimation of the temperature, and underestimation of hotspot rho-r, energy, and ignition margin. In this work, we analyze these effects in NIF data, and propose new methods to avoid them. These simple, analytical methods are tested using the largest 2D ICF simulation dataset ever produced. Work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA273.

  15. Triton burnup measurements in KSTAR using a neutron activation system

    Science.gov (United States)

    Jo, Jungmin; Cheon, MunSeong; Kim, Jun Young; Rhee, T.; Kim, Junghee; Shi, Yue-Jiang; Isobe, M.; Ogawa, K.; Chung, Kyoung-Jae; Hwang, Y. S.

    2016-11-01

    Measurements of the time-integrated triton burnup for deuterium plasma in Korea Superconducting Tokamak Advanced Research (KSTAR) have been performed following the simultaneous detection of the d-d and d-t neutrons. The d-d neutrons were measured using a 3He proportional counter, fission chamber, and activated indium sample, whereas the d-t neutrons were detected using activated silicon and copper samples. The triton burnup ratio from KSTAR discharges is found to be in the range 0.01%-0.50% depending on the plasma conditions. The measured burnup ratio is compared with the prompt loss fraction of tritons calculated with the Lorentz orbit code and the classical slowing-down time. The burnup ratio is found to increase as plasma current and classical slowing-down time increase.

  16. A novel explicit 2D+t cyclic shape model applied to echocardiography.

    Science.gov (United States)

    Casero, Ramón; Noble, J Alison

    2008-01-01

    In this paper, we propose a novel explicit 2D+t cyclic shape model that extends the Point Distribution Model (PDM) to shapes like myocardial contours with cyclic dynamics. We also propose an extension to Procrustes alignment that removes pose and subject size variability while maintaining dynamic effects. Our model draws on ideas from Principal Component Analysis (PCA), Multidimensional Scaling (MDS) and Kernel PCA (KPCA) and solves 3 shortcomings of previous implicit models: (1) cardiac cycles in the data set do not each need to have the same number of frames, (2) the required number of subjects for statistically significant results is substantially reduced and (3) the displacement of contour points incorporates time as an explicit variable. We illustrate our method by computing models of the myocardium in the 4 principal planes of 2D+t echocardiography data.

  17. Muon cycling rate in D/T mixture including doubly muonic molecule formation

    Directory of Open Access Journals (Sweden)

    M. R. Eskandari

    2002-06-01

    Full Text Available   In the present work, the fundamental behavior of four body molecule formations of pt μμ , pd μμ , dt μμ , tt μμ , and pp μμ in a D/T fusion are considered. Their higher fusion rate, specially the available data for dt μμ , encouraged us to study the muon cycling rate in D/T fusion in the temperature range of (100-1400 K, density and deuterium-tritium concentration ratio. For this purpose, various values for the doubly muonic molecule formation are chosen and with the comparison to the experimental results, the doubly muonic formation rate of 109 s-1 is predicted theoretically. Our calculated cycling rate has shown that having not considered the doubly muonic formation in previous calculations had made no serious changes in the previously calculated values.

  18. Cross Sections Calculations of ( d, t) Nuclear Reactions up to 50 MeV

    Science.gov (United States)

    Tel, E.; Yiğit, M.; Tanır, G.

    2013-04-01

    In nuclear fusion reactions two light atomic nuclei fuse together to form a heavier nucleus. Fusion power is the power generated by nuclear fusion processes. In contrast with fission power, the fusion reaction processes does not produce radioactive nuclides. The fusion will not produce CO2 or SO2. So the fusion energy will not contribute to environmental problems such as particulate pollution and excessive CO2 in the atmosphere. Fusion powered electricity generation was initially believed to be readily achievable, as fission power had been. However, the extreme requirements for continuous reactions and plasma containment led to projections being extended by several decades. In 2010, more than 60 years after the first attempts, commercial power production is still believed to be unlikely before 2050. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. In the fusion reactor, tritium self-sufficiency must be maintained for a commercial power plant. Therefore, for self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of ( d, t) nuclear reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. Since the experimental data of charged particle induced reactions are scarce, self-consistent calculation and analyses using nuclear theoretical models are very important. In this study, ( d, t) cross sections for target nuclei 19F, 50Cr, 54Fe, 58Ni, 75As, 89Y, 90Zr, 107Ag, 127I, 197Au and 238U have been investigated up to 50 MeV deuteron energy. The excitation functions for ( d, t) reactions have been calculated by pre-equilibrium reaction mechanism. Calculation results have been also compared with the available measurements in

  19. Temperature derivatives for fusion reactivity of D-D and D-T

    Energy Technology Data Exchange (ETDEWEB)

    Langenbrunner, James R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Makaruk, Hanna Ewa [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-29

    Deuterium-tritium (D-T) and deuterium-deuterium (D-D) fusion reaction rates are observable using leakage gamma flux. A direct measurement of γ-rays with equipment that exhibits fast temporal response could be used to infer temperature, if the detector signal is amenable for taking the logarithmic time-derivative, alpha. We consider the temperature dependence for fusion cross section reactivity.

  20. Neutron dosimetry; Dosimetria de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Fratin, Luciano

    1993-12-31

    A neutron irradiation facility was designed and built in order to establish a procedure for calibrating neutron monitors and dosemeters. A 185 GBq {sup 241} Am Be source of known is used as a reference source. The irradiation facility using this source in the air provides neutron dose rates between 9 nSv s{sup -1} and 0,5 {sup {mu}}Sv s{sup -1}. A calibrated 50 nSv s{sup -1} thermal neutron field is obtained by using a specially designed paraffin block in conjunction with the {sup 241} Am Be source. A Bonner multisphere spectrometer was calibrated, using a procedure based on three methods proposed by international standards. The unfold {sup 241} Am Be neutron spectrum was determined from the Bonner spheres data and resulted in a good agreement with expected values for fluence rate, dose rate and mean energy. A dosimetric system based on the electrochemical etching of CR-39 was developed for personal dosimetry. The dosemeter badge using a (n,{alpha}) converter, the etching chamber and high frequency power supply were designed and built specially for this project. The electrochemical etching (ECE) parameters used were: a 6N KOH solution, 59 deg C, 20 kV{sub pp} cm{sup -1}, 2,0 kHz, 3 hours of ECE for thermal and intermediate neutrons and 6 hours for fast neutrons. The calibration factors for thermal, intermediate and fast neutrons were determined for this personal dosemeter. The sensitivities determined for the developed dosimetric system were (1,46{+-} 0,09) 10{sup 4} tracks cm{sup -2} mSv{sup -1} for thermal neutrons, (9{+-}3) 10{sup 2} tracks cm{sup -2} mSV{sup -1} for intermediate neutrons and (26{+-}4) tracks cm{sup -2} mSv{sup -1} for fast neutrons. The lower and upper limits of detection were respectively 0,002 mSv and 0,6 mSv for thermal neutrons, 0,04 mSv and 8 mSv for intermediate neutrons and 1 mSv and 12 mSv for fast neutrons. In view of the 1990`s ICRP recommendations, it is possible to conclude that the personal dosemeter described in this work is

  1. Neutron kinetics in moderators and SNM detection through epithermal-neutron-induced fissions

    Science.gov (United States)

    Gozani, Tsahi; King, Michael J.

    2016-01-01

    Extension of the well-established Differential Die Away Analysis (DDAA) into a faster time domain, where more penetrating epithermal neutrons induce fissions, is proposed and demonstrated via simulations and experiments. In the proposed method the fissions stimulated by thermal, epithermal and even higher-energy neutrons are measured after injection of a narrow pulse of high-energy 14 MeV (d,T) or 2.5 MeV (d,D) source neutrons, appropriately moderated. The ability to measure these fissions stems from the inherent correlation of neutron energy and time ("E-T" correlation) during the process of slowing down of high-energy source neutrons in common moderating materials such as hydrogenous compounds (e.g., polyethylene), heavy water, beryllium and graphite. The kinetic behavior following injection of a delta-function-shaped pulse (in time) of 14 MeV neutrons into such moderators is studied employing MCNPX simulations and, when applicable, some simple "one-group" models. These calculations served as a guide for the design of a source moderator which was used in experiments. Qualitative relationships between slowing-down time after the pulse and the prevailing neutron energy are discussed. A laboratory system consisting of a 14 MeV neutron generator, a polyethylene-reflected Be moderator, a liquid scintillator with pulse-shape discrimination (PSD) and a two-parameter E-T data acquisition system was set up to measure prompt neutron and delayed gamma-ray fission signatures in a 19.5% enriched LEU sample. The measured time behavior of thermal and epithermal neutron fission signals agreed well with the detailed simulations. The laboratory system can readily be redesigned and deployed as a mobile inspection system for SNM in, e.g., cars and vans. A strong pulsed neutron generator with narrow pulse (<75 ns) at a reasonably high pulse frequency could make the high-energy neutron induced fission modality a realizable SNM detection technique.

  2. Neutron kinetics in moderators and SNM detection through epithermal-neutron-induced fissions

    Energy Technology Data Exchange (ETDEWEB)

    Gozani, Tsahi, E-mail: tgmaven@gmail.com [1050 Harriet St., Palo Alto, CA 94301 (United States); King, Michael J. [Rapiscan Laboratories Inc., 520 Almanor Ave., Sunnyvale, CA 94085 (United States)

    2016-01-01

    Extension of the well-established Differential Die Away Analysis (DDAA) into a faster time domain, where more penetrating epithermal neutrons induce fissions, is proposed and demonstrated via simulations and experiments. In the proposed method the fissions stimulated by thermal, epithermal and even higher-energy neutrons are measured after injection of a narrow pulse of high-energy 14 MeV (d,T) or 2.5 MeV (d,D) source neutrons, appropriately moderated. The ability to measure these fissions stems from the inherent correlation of neutron energy and time (“E–T” correlation) during the process of slowing down of high-energy source neutrons in common moderating materials such as hydrogenous compounds (e.g., polyethylene), heavy water, beryllium and graphite. The kinetic behavior following injection of a delta-function-shaped pulse (in time) of 14 MeV neutrons into such moderators is studied employing MCNPX simulations and, when applicable, some simple “one-group” models. These calculations served as a guide for the design of a source moderator which was used in experiments. Qualitative relationships between slowing-down time after the pulse and the prevailing neutron energy are discussed. A laboratory system consisting of a 14 MeV neutron generator, a polyethylene-reflected Be moderator, a liquid scintillator with pulse-shape discrimination (PSD) and a two-parameter E–T data acquisition system was set up to measure prompt neutron and delayed gamma-ray fission signatures in a 19.5% enriched LEU sample. The measured time behavior of thermal and epithermal neutron fission signals agreed well with the detailed simulations. The laboratory system can readily be redesigned and deployed as a mobile inspection system for SNM in, e.g., cars and vans. A strong pulsed neutron generator with narrow pulse (<75 ns) at a reasonably high pulse frequency could make the high-energy neutron induced fission modality a realizable SNM detection technique.

  3. Foil deposition alpha collector probe for TFTR`s D-T phase

    Energy Technology Data Exchange (ETDEWEB)

    Hermann, H.W.; Darrow, D.S.; Timberlake, J.; Zweben, S.J. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Chong, G.P.; Pitcher, C.S. [Toronto Univ., ON (Canada). Inst. for Aerospace Studies; Macaulay-Newcombe, R.G. [McMaster Univ., Hamilton, ON (Canada). Dept. of Engineering Physics

    1995-03-01

    A new foil deposition alpha collector sample probe has been developed for TFTR`s D-T phase. D-T fusion produced alpha particles escaping from the plasma are implanted in nickel foils located in a series of collimating ports on the detector. The nickel foils are removed from the tokamak after exposure to one or more plasma discharges and analyzed for helium content. This detector is intended to provide improved alpha particle energy resolution and pitch angle coverage over existing lost alpha detectors, and to provide an absolutely calibrated cross-check with these detectors. The ability to resolve between separate energy components of alpha particle loss is estimated to be {approx} 20%. A full 360{degree} of pitch angle coverage is provided for by 8 channels having an acceptance range of {approx} 53{degree} per channel. These detectors will be useful in characterizing classical and anomalous alpha losses and any collective alpha instabilities that may be excited during the D-T campaign of TFTR.

  4. High yield purification of full-length functional hERG K+ channels produced in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Molbaek, Karen; Scharff-Poulsen, Peter; Hélix-Nielsen, Claus;

    2015-01-01

    knowledge this is the first reported high-yield production and purification of full length, tetrameric and functional hERG. This significant breakthrough will be paramount in obtaining hERG crystal structures, and in establishment of new high-throughput hERG drug safety screening assays....

  5. BRS 369RF and BRS 370RF: Glyphosate tolerant, high-yielding upland cotton cultivars for central Brazilian savanna

    Directory of Open Access Journals (Sweden)

    Camilo de Lelis Morello

    2015-12-01

    Full Text Available BRS 369RF and BRS 370RF were developed by the EMBRAPA as a part of efforts to create high-yielding germplasm with combinations of transgenic traits. BRS 369RF and BRS 370RF are midseason cultivars and have yield stability, adaptation to the central Brazilian savanna, good fiber quality and tolerance to glyphosate herbicide.

  6. BRS FC402: high-yielding common bean cultivar with carioca grain, resistance to anthracnose and fusarium wilt

    Directory of Open Access Journals (Sweden)

    Leonardo Cunha Melo

    2016-12-01

    Full Text Available BRS FC402 is a common bean cultivar of the carioca-grain group with commercial grain quality, suitable for cultivation in 21 Brazilian states. Cultivar has a normal cycle (85-94 days, high yield potential (4479 kg ha-1, 10.1% higher mean yield than the controls (2462 kg ha-1 and resistance to fusarium wilt and anthracnose.

  7. A possible approach to 14MeV neutron moderation: A preliminary study case.

    Science.gov (United States)

    Flammini, D; Pilotti, R; Pietropaolo, A

    2017-07-01

    Deuterium-Tritium (D-T) interactions produce almost monochromatic neutrons with about 14MeV energy. These neutrons are used in benchmark experiments as well as for neutron cross sections assessment in fusion reactors technology. The possibility to moderate 14MeV neutrons for purposes beyond fusion is worth to be studied in relation to projects of intense D-T sources. In this preliminary study, carried out using the MCNP Monte Carlo code, the moderation of 14MeV neutrons is approached foreseeing the use of combination of metallic materials as pre-moderator and reflectors coupled to standard water moderators. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Neutron reflectometry

    DEFF Research Database (Denmark)

    Klösgen-Buchkremer, Beate Maria

    2014-01-01

    films or films with magnetic properties. The reason is the peculiar property of neutron light since the mass of a neutron is close to the one of a proton, and since it bears a magnetic moment. The optical properties of matter, when interacting with neutrons, are described by a refractive index......Neutron (and X-ray) reflectometry constitute complementary interfacially sensitive techniques that open access to studying the structure within thin films of both soft and hard condensed matter. Film thickness starts oxide surfaces on bulk substrates, proceeding to (pauci-)molecular layers and up...... to hundreds of nanometers. Thickness resolution for flat surfaces is in the range of few Ǻngstrøm, and as a peculiar benefit, the presence and properties of buried interfaces are accessible. Focus here will be on neutron reflectometry, a technique that is unique in applications involving composite organic...

  9. Designing of the 14 MeV neutron moderator for BNCT

    Institute of Scientific and Technical Information of China (English)

    CHENG Dao-Wen; LU Jing-Bin; YANG Dong; LIU Yu-Min; WANG Hui-Dong; MA Ke-Yan

    2012-01-01

    In boron neutron capture therapy (BNCT),the ratio of the fast neutron flux to the neutron flux in the tumor (RFNT) must be less than 3%.If a D-T neutron generator is used in BNCT,the 14 MeV neutron moderator must be optimized to reduce the RFNT.Based on the neutron moderation theory and the simulation results,tungsten,lead and diamond were used to moderate the 14 MeV neutrons.Satisfying RFNT of less than 3%,the maximum neutron flux in the tumor was achieved with a three-layer moderator comprised of a 3 cm thick tungsten layer,a 14 cm thick lead layer and a 21 cm thick diamond layer.

  10. Fast neutron spectrometry with organic scintillators applied to magnetic fusion experiments

    CERN Document Server

    Kaschuck, Y A; Trykov, L A; Semenov, V P

    2002-01-01

    Neutron spectrometry with NE213 liquid scintillators is commonly used in thermonuclear fusion experiments to measure the 2.45 and 14.1 MeV neutron flux. We present the unfolded neutron spectrum, which was accumulated during several ohmic deuterium plasma discharges in the Frascati Tokamak Upgrade using a 2''x2'' NE213 scintillator. In this paper, we review the application of organic scintillator neutron spectrometers to tokamaks, focusing in particular on the comparison between NE213 and stilbene scintillators. Various aspects of the calibration technique and neutron spectra unfolding procedure are considered in the context of their application for fusion neutron spectrometry. Testing and calibration measurements have been carried out using D-D and D-T neutron generator facilities with both NE213 and stilbene scintillators. The main result from these measurements is that stilbene scintillator has better neutron energy resolution than NE213. Our stilbene detector could be used for the determination of the ion ...

  11. Detection of buried explosives using portable neutron sources with nanosecond timing.

    Science.gov (United States)

    Kuznetsov, A V; Evsenin, A V; Gorshkov, I Yu; Osetrov, O I; Vakhtin, D N

    2004-07-01

    Significant reduction of time needed to identify hidden explosives and other hazardous materials by the "neutron in, gamma out" method has been achieved by introducing timed (nanosecond) neutron sources-the so-called nanosecond neutron analysis technique. Prototype mobile device for explosives' detection based on a timed (nanosecond) isotopic (252)Cf neutron source has been created. The prototype is capable of identifying 400 g of hidden explosives in 10 min. Tests have been also made with a prototype device using timed (nanosecond) neutron source based on a portable D-T neutron generator with built-in segmented detector of accompanying alpha-particles. The presently achieved intensity of the neutron generator is 5x10(7)n/s into 4pi, with over 10(6) of these neutrons being correlated with alpha-particles detected by the built-in alpha-particle detector. Results of measurements with an anti-personnel landmine imitator are presented.

  12. Neutron spectrometry at JET (1983-1999)

    CERN Document Server

    Jarvis, O N

    2002-01-01

    An account is given of the neutron spectrometric measurements on tokamak plasmas that have been performed at the Joint European Torus (JET) Joint Undertaking. The original restrictions for physical access to the tokamak and the performance projections are described. The actual characteristics of JET plasmas as intense but highly transient sources of neutrons are then presented. Next, the various neutron spectrometers that have been deployed at JET are listed and their success in meeting the demands of the JET experiment is appraised. Finally, there is a discussion of the plasma physics considerations that determine the detailed shapes of the d-d and d-t spectral lines under the various plasma conditions and spectrometer viewing directions and of the results obtained.

  13. Helix-coil transition of the self-complementary dG-dG-dA-dA-dT-dT-dC-dC duplex.

    Science.gov (United States)

    Patel, D J; Canuel, L L

    1979-05-15

    The helix-coil transition of the octanucleotide self-complementary duplex dG-dG-dA-dA-dT-dT-dC-dC has been monitored at the Watson-Crick protons, the base and sugar nonexchangeable protons and the backbone phosphates by high-resolution nuclear magnetic resonance (NMR) spectroscopy. The melting transition of the octanucleotide monitored by ultraviolet absorbance spectroscopy is characterized by the thermodynamic parameters delta H degree = -216.7 kJ/mol and delta S degree (25 degrees C) = -0.632 KJ mol-1 K-1 in 0.1 M NaCl, 10 mM phosphate solution. Correlation of the transition midpoint values monitored by the ultraviolet absorbance studies at strand concentrations below 0.2 mM and by NMR studies at 5.3 mM suggest that both methods are monitoring the octanucleotide duplex-to-strand transition. The NMR spectra of the Watson-Crick ring NH protons of the octanucleotide duplex have been followed as a function of temperature. The resonance from the terminal dG.dC base pairs broadens out at room temperature while the resonances from the other base pairs broaden simultaneously with the onset of the melting transition. The nonexchangeable base and sugar H-1' protons are resolved in the duplex and strand states and shift as average peaks through the melting transition. The experimental shifts on duplex formation have been compared with calculated values based on ring-current and atomic diamagnetic anisotropy contributions for a B-DNA base-pair-overlap geometry in solution. Several nonexchangeable proton resonances broaden in the fast-exchange region during the duplex-to-strand transition and the excess widths yield a duplex dissociation rate constant for the octanucleotide of 1.9 x 10(3) s-1 at 32 degrees C (fraction of duplex = 0.86) in 0.1 M NaCl, 10 mM phosphate buffer. The 31P resonances of the seven internucleotide phosphates are distributed over 0.6 ppm in the duplex state, shift downfield during the duplex-to-strand transition and undergo additional downfield shifts

  14. DIANE: Advanced system for mobile neutron radiology

    Science.gov (United States)

    Dance, W. E.; Huriet, J. R.; Cluzeau, S.; Mast, H.-U.; Albisu, F.

    1989-04-01

    Development of a new neutron radiology system, DIANE, is underway which will provide a ten-fold improvement in image-acquisition speed over presently operating mobile systems, insuring greater inspection throughput for production applications. Based on a 10 12 n/s sealed-tube (D-T) neutron generator under development by Sodern, on LTV's neutron moderator/collimator and electronic imaging systems and on robotic and safety systems being developed by IABG and Sener, the DIANE concept is that of a complete facility for on-site neutron radiography or radioscopy. The LTV components, which provide film or electronic imaging, including digital processing of 12-bit images, have been demonstrated in three basic systems now operating with Kaman A-711 neutron generators, including one operating in IABG's facilities. Sodern has fabricated a prototype neutron generator tube, the TN 46, for emission of 10 11 n/s over 1000 to 1500 hours, at 250 kV and 2 mA in the ion beam.

  15. Transcriptome Analysis Suggests That Starch Synthesis May Proceed via Multiple Metabolic Routes in High Yielding Potato Cultivars

    DEFF Research Database (Denmark)

    Kaminski, Kacper Piotr; Høgh Petersen, Annabeth; Sønderkær, Mads

    2012-01-01

    Background: Glucose-6-phosphate is imported into the amyloplast of potato tubers and thought to constitute the precursor for starch synthesis in potato tubers. However, recently it was shown that glucose-1-phosphate can also be imported into the amyloplast and incorporated into starch via an ATP...... independent mechanism under special conditions. Nonetheless, glucose 6-phosphate is believed to be the quantitatively important precursor for starch synthesis in potato. Principal Finding: Potato tubers of the high yielding cv Kuras had low gene expression of plastidial phophoglucomutase (PGM) and normal...... to expectations, this combination lead to a higher level of intracellular glucose-1-phosphate (G1P) in Kuras suggesting that G1P is directly imported into plastids and can be quantitatively important for starch synthesis under normal conditions in high yielding cultivars. Significance: This could open entirely...

  16. Assessment on Carbon Sequestration Benefit of Fast-growing and High-yielding Forest Base Construction Program

    Institute of Scientific and Technical Information of China (English)

    Ru Taoqin; Li Jiyue; Zhuo Weihua; Li Xiangdong; Zhang Wenjie

    2004-01-01

    Fast-growing and High-yielding Forests Base Construction Program is the only industrialization program of six key forestry programs. The main construction content is to plant 13.33 million hm fast-growing and high-yielding plantation in 18 provinces in China. According to the program planning and growth of different tree species, the biomass of this program is evaluated and the C sequestration is assessed in this paper. In the program period, the biomass of the program will reach 3.703 6×109 t, and the C storage will get 1.851 8×109 t. The program will have a great effect on raising the C pool function of forest vegetation.

  17. Structure of 26Al studied by one - nucleon transfer reaction 27Al(d,t

    Directory of Open Access Journals (Sweden)

    Srivastava Vishal

    2015-01-01

    Full Text Available The excited states of 26Al have been produced and studied using 27Al(d,t reaction with 25 MeV deuteron as projectile. Optical model potential parameters were extracted from the measured elastic scattering angular distribution. Zero range distorted wave Born approximation analysis for the ground and 0.223 MeV states of 26Al have been done. The spectroscopic factors calculated for these states are found to be in good agreement with the previously reported values.

  18. Excited states of 26Al studied via the reaction 27Al(d,t

    Directory of Open Access Journals (Sweden)

    Srivastava Vishal

    2016-01-01

    Full Text Available The reaction 27Al(d,t at 25 MeV was utilized to study the excited states of 26Al. The angular distributions of the observed excited states of 26Al were analyzed with zero range distorted wave Born approximation as well as by incorporating finite range correction parameters to extract spectroscopic factors. The two sets of extracted spectroscopic factors were compared with each other to see the effect of using finite range correction in the transfer form factor.

  19. High Precision and High Yield Fabrication of Dense Nanoparticle Arrays onto DNA Origami at Statistically Independent Binding Sites †

    OpenAIRE

    Takabayashi, Sadao; Klein, William P.; Onodera, Craig; Rapp, Blake; Flores-Estrada, Juan; Lindau, Elias; Snowball, Lejmarc; Sam, Joseph Tyler; Padilla, Jennifer E.; Lee, Jeunghoon; Knowlton, William B.; Graugnard, Elton; Yurke, Bernard; Kuang, Wan; Hughes, William L.

    2014-01-01

    High precision, high yield, and high density self-assembly of nanoparticles into arrays is essential for nanophotonics. Spatial deviations as small as a few nanometers can alter the properties of near-field coupled optical nanostructures. Several studies have reported assemblies of few nanoparticle structures with controlled spacing using DNA nanostructures with variable yield. Here, we report multi-tether design strategies and attachment yields for homo- and hetero-nanoparticle arrays templa...

  20. Productivity, Profitability and Resource Use Efficiency: A Comparative Analysis between Conventional and High Yielding Rice in Rajbari District, Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Yahia Bapari

    2016-10-01

    Full Text Available The study was analyzed the determinants, costs and benefits and resources allocation of both conventional and high yielding rice cultivation over the Rajbari district of Bangladesh. Data were accumulated from 300 regular rice growers of conventional and high yielding varieties and random sampling technique was applied for selecting the respondents from the study area from which information was collected through pre-tested questionnaire. Cobb – Douglas production function and gross margin were mainly used to determine the productivities and profits of both rice and the marginal value of the product was highly recommended to derive the optimal use of the resources. Results obtained by applying ordinary least square method showed that the most important factors of production in the study area were irrigation, labor, fertilizer and insecticide costs whose elasticities were 0.904, 0.048, 0.045 and 0.044 respectively and insignificant factors were seed and ploughing costs whose elasticities were – 0.009 and 0.030 respectively for high yielding rice. On the other hand, irrigation, insecticide, seed and ploughing costs of elasticities 0.880, 0.589, 0.116 and – 0.127 respectively were the important factors and minor role playing factors were labor and fertilizer costs whose elasticities were 0.098 and 0.077 respectively for conventional yielding rice. The core message from productivity analysis was that the irrigation was key variable which played a positive and vital role in producing rice of both varieties. All variables (resources were economically misallocated in the production activities of both varieties along the study area but high yielding rice was more profitable than conventional one. Results also showed that the farmers of the study area produced rice of both varieties in the inefficient range of production. Continuous supply of electricity, flexible credit and improving the existing resources were the prime policy recommendations of

  1. Rapid high-yield expression of full-size IgG antibodies in plants coinfected with noncompeting viral vectors

    OpenAIRE

    Giritch, Anatoli; Marillonnet, Sylvestre; Engler, Carola; van Eldik, Gerben; Botterman, Johan; Klimyuk, Victor; Gleba, Yuri

    2006-01-01

    Plant viral vectors allow expression of heterologous proteins at high yields, but so far, they have been unable to express heterooligomeric proteins efficiently. We describe here a rapid and indefinitely scalable process for high-level expression of functional full-size mAbs of the IgG class in plants. The process relies on synchronous coinfection and coreplication of two viral vectors, each expressing a separate antibody chain. The two vectors are derived from two different plant viruses tha...

  2. A high-yielding, generic fed-batch process for recombinant antibody production of GS-engineered cell lines

    DEFF Research Database (Denmark)

    Fan, Li; Zhao, Liang; Sun, Yating;

    2009-01-01

    An animal component-free and chemically defined fed-batch process for GS-engineered cell lines producing recombinant antibodies has been developed. The fed-batch process relied on supplying sufficient nutrients to match their consumption, simultaneously minimizing the accumulation of byproducts....... This generic and high-yielding fed-batch process would shorten development time, and ensure process stability, thereby facilitating the manufacture of therapeutic antibodies by GS-engineered cell lines....

  3. High-yielding aquifers in crystalline basement: insights about the role of fault zones, exemplified by Armorican Massif, France

    Science.gov (United States)

    Roques, Clément; Bour, Olivier; Aquilina, Luc; Dewandel, Benoît

    2016-12-01

    While groundwater constitutes a crucial resource in many crystalline-rock regions worldwide, well-yield conditions are highly variable and barely understood. Nevertheless, it is well known that fault zones may have the capacity to ensure sustainable yield in crystalline media, but there are only a few and disparate examples in the literature that describe high-yield conditions related to fault zones in crystalline rock basements. By investigating structural and hydraulic properties of remarkable yielding sites identified in the Armorican Massif, western France, this study discusses the main factors that may explain such exceptional hydrogeological properties. Twenty-three sites, identified through analysis of databases available for the region, are investigated. Results show that: (1) the highly transmissive fractures are related to fault zones which ensure the main water inflow in the pumped wells; (2) the probability of intersecting such transmissive fault zones does not vary significantly with depth, at least within the range investigated in this study (0-200 m); and (3) high yield is mainly controlled by the structural features of the fault zones, in particular the fault dip and the presence of a connected storage reservoir. Conceptual models that summarize the hydrological properties of high-yield groundwater resources related to fault zones in crystalline basement are shown and discussed.

  4. Calibration of NIF neutron detectors in the energy region E<14 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, G J; Moran, M J; Koch, J A; Phillips, T W; Glebov, V Y; Sangster, T C; Stoeckl, C; Wender, S A; Morse, E C

    2004-04-09

    We examine various options for calibration of NIF neutron detectors in the energy region E<14 MeV. These options include: downscatter of D-T fusion neutrons using plastic targets; nuclear reactions at a Tandem Van de Graaf accelerator; and ''white'' neutrons from a pulsed spallation source. As an example of the spallation option, we present some calibration data that was recently obtained with a single crystal CVD diamond detector at the Weapons Neutron Research facility (WNR) at LANL.

  5. Dual-fission chamber and neutron beam characterization for fission product yield measurements using monoenergetic neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Bhatia, C.; Fallin, B. [Department of Physics, Duke University, Durham, NC 27708 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Gooden, M.E., E-mail: megooden@tunl.duke.edu [Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Department of Physics, North Carolina State University, Raleigh, NC 27605 (United States); Howell, C.R. [Department of Physics, Duke University, Durham, NC 27708 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Kelley, J.H. [Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Department of Physics, North Carolina State University, Raleigh, NC 27605 (United States); Tornow, W. [Department of Physics, Duke University, Durham, NC 27708 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Arnold, C.W.; Bond, E.M.; Bredeweg, T.A.; Fowler, M.M.; Moody, W.A.; Rundberg, R.S.; Rusev, G.; Vieira, D.J.; Wilhelmy, J.B. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Becker, J.A.; Macri, R.; Ryan, C.; Sheets, S.A.; Stoyer, M.A. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); and others

    2014-09-01

    A program has been initiated to measure the energy dependence of selected high-yield fission products used in the analysis of nuclear test data. We present out initial work of neutron activation using a dual-fission chamber with quasi-monoenergetic neutrons and gamma-counting method. Quasi-monoenergetic neutrons of energies from 0.5 to 15 MeV using the TUNL 10 MV FM tandem to provide high-precision and self-consistent measurements of fission product yields (FPY). The final FPY results will be coupled with theoretical analysis to provide a more fundamental understanding of the fission process. To accomplish this goal, we have developed and tested a set of dual-fission ionization chambers to provide an accurate determination of the number of fissions occurring in a thick target located in the middle plane of the chamber assembly. Details of the fission chamber and its performance are presented along with neutron beam production and characterization. Also presented are studies on the background issues associated with room-return and off-energy neutron production. We show that the off-energy neutron contribution can be significant, but correctable, while room-return neutron background levels contribute less than <1% to the fission signal.

  6. Neutron Repulsion

    CERN Document Server

    Manuel, Oliver K

    2011-01-01

    Earth is connected gravitationally, magnetically and electrically to its heat source - a neutron star that is obscured from view by waste products in the photosphere. Neutron repulsion is like the hot filament in an incandescent light bulb. Excited neutrons are emitted from the solar core and decay into hydrogen that glows in the photosphere like a frosted light bulb. Neutron repulsion was recognized in nuclear rest mass data in 2000 as the overlooked source of energy, the keystone of an arch that locked together these puzzling space-age observations: 1.) Excess 136Xe accompanied primordial helium in the stellar debris that formed the solar system (Fig. 1); 2.) The Sun formed on the supernova core (Fig. 2); 3.) Waste products from the core pass through an iron-rich mantle, selectively carrying lighter elements and lighter isotopes of each element into the photosphere (Figs. 3-4); and 4.) Neutron repulsion powers the Sun and sustains life (Figs. 5-7). Together these findings offer a framework for understanding...

  7. High yield cultivation technology of summer corn%夏玉米优质高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    郭雪莲

    2011-01-01

    依据夏玉米各生育阶段的主攻目标,通过对夏玉米各生育阶段生长发育的调查、分析,总结出适合夏玉米高产稳产的管理及栽培技术。%On the basis of summer corn in different growth stages of the main attack target, through to summer maize at different growth stages of growth and development survey, analysis, summed up for summer maize high yield management and cultivation techniques.

  8. Unravelling the mechanisms behind mixed catalysts for the high yield production of single-walled carbon nanotubes.

    Science.gov (United States)

    Tetali, Sailaja; Zaka, Mujtaba; Schönfelder, Ronny; Bachmatiuk, Alicja; Börrnert, Felix; Ibrahim, Imad; Lin, Jarrn H; Cuniberti, Gianaurelio; Warner, Jamie H; Büchner, Bernd; Rümmeli, Mark H

    2009-12-22

    The use of mixed catalysts for the high-yield production of single-walled carbon nanotubes is well-known. The mechanisms behind the improved yield are poorly understood. In this study, we systematically explore different catalyst combinations from Ni, Co, and Mo for the synthesis of carbon nanotubes via laser evaporation. Our findings reveal that the mixing of catalysts alters the catalyst cluster size distribution, maximizing the clusters' potential to form a hemispherical cap at nucleation and, hence, form a single-walled carbon nanotube. This process significantly improves the single-walled carbon nanotube yields.

  9. Neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Heger, G. [Rheinisch-Westfaelische Technische Hochschule Aachen, Inst. fuer Kristallographie, Aachen (Germany)

    1996-12-31

    X-ray diffraction using conventional laboratory equipment and/or synchrotron installations is the most important method for structure analyses. The purpose of this paper is to discuss special cases, for which, in addition to this indispensable part, neutrons are required to solve structural problems. Even though the huge intensity of modern synchrotron sources allows in principle the study of magnetic X-ray scattering the investigation of magnetic structures is still one of the most important applications of neutron diffraction. (author) 15 figs., 1 tab., 10 refs.

  10. Application of the X-ray laser to muon-catalyzed d-t fusion

    CERN Document Server

    Kimura, Sachie; 10.1080/10420150701777991

    2008-01-01

    We discuss the alpha-muon sticking coefficient in the muon-catalysed d-t fusion in the framework of the Constrained Molecular Dynamics model. Especially the influence of muonic chaotic dynamics on the sticking coefficient is brought into focus. The chaotic motion of the muon affects not only the fusion cross section but also the muon-alpha sticking coefficient. Chaotic systems lead to lar ger enhancements with respect to regular systems because of the reduction of the tunneling region. Moreover they give smaller sticking probabilities than those of regular events. By utilizing a characteristic of the chaotic dynamics one can avoid losing the muon in the muCF cycle. W e propose that the application of the so-called microwave ionization of a Rydberg atom to the present case could lead to the enhancement of the reactivation process by using X-rays.

  11. Alpha-muon sticking and chaos in muon-catalysed d-t fusion

    CERN Document Server

    Kimura, S; Kimura, Sachie; Bonasera, Aldo

    2006-01-01

    We discuss the alpha-muon sticking coefficient in the muon-catalysed d-t fusion in the framework of the Constrained Molecular Dynamics model. Especially the influence of muonic chaotic dynamics on the sticking coefficient is brought into focus. The chaotic motion of the muon affects not only the fusion cross section but also the $\\mu-\\alpha$ sticking coefficient. Chaotic systems lead to larger enhancements with respect to regular systems because of the reduction of the tunneling region. Moreover they give smaller sticking probabilities than those of regular events. By utilizing a characteristic of the chaotic dynamics one can avoid losing the muon in the $\\mu$CF cycle. We propose that the application of the so-called "microwave ionization of a Rydberg atom" to the present case could lead to the enhancement of the reactivation process by using X-rays.

  12. Study of sup 1 sup 1 sup 9 Te with the (d,t) reaction

    CERN Document Server

    Bucurescu, D; Wirth, H F; Marginean, N; Köster, U; Graw, G; Metz, A; Hertenberger, R; Eisermann, Y

    2000-01-01

    The structure of the nucleus sup 1 sup 1 sup 9 Te has been studied with the sup 1 sup 2 sup 0 Te( d,t) reaction at E sub d =24.0 MeV. Almost 90 excited states have been observed up to an excitation energy of 2.5 MeV, and spin and parity values have been assigned to many of them. The existing experimental data are compared with calculations made on the basis of the Interacting Boson-Fermion Model-1. The large number of low-spin states observed up to about 1.2 MeV is well accounted for, whereas at higher energies the correspondence of calculated states with experimental ones becomes unreliable. The possibility of the occurrence of 'intruder' states is also discussed.

  13. Neutronics of pulsed spallation neutron sources

    CERN Document Server

    Watanabe, N

    2003-01-01

    Various topics and issues on the neutronics of pulsed spallation neutron sources, mainly for neutron scattering experiments, are reviewed to give a wide circle of readers a better understanding of these sources in order to achieve a high neutronic performance. Starting from what neutrons are needed, what the spallation reaction is and how to produce slow-neutrons more efficiently, the outline of the target and moderator neutronics are explained. Various efforts with some new concepts or ideas have already been devoted to obtaining the highest possible slow-neutron intensity with desired pulse characteristics. This paper also reviews the recent progress of such efforts, mainly focused on moderator neutronics, since moderators are the final devices of a neutron source, which determine the source performance. Various governing parameters for neutron-pulse characteristics such as material issues, geometrical parameters (shape and dimensions), the target-moderator coupling scheme, the ortho-para-hydrogen ratio, po...

  14. Are Design and Technology Teachers Able to Meet the Challenges Inherent in the Theme for This Conference "D&T--A Platform for Success"?

    Science.gov (United States)

    Atkinson, E. Stephanie

    2009-01-01

    This paper has emerged out of the author's life-long passion for Design and Technology (D&T), which she will refer to as D&T from now on, her on-going research which has informed her practice as a teacher of D&T in England over the past 45 years, and in particular her practice as a trainer of D&T teachers for the past 20 years. In…

  15. Study on the Practice and High-yielding Mechanism of Super-sparse-cultivation Associated with Maximum-tiller Seedling of Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    MA Jun; TAO Shi-shun

    2002-01-01

    In this paper, a new cultivation practice-super-sparse-cultivation associated with maximumtiller seedling (SSCMTS) of hybrid rice was proposed and its high-yielding mechanism was studied. The results showed that the practice of SSCMTS in hybrid rice could not only increase grain yield but also save seeds and labor. It was a new high-yielding way for the late transplanting seedlings and heavy panicle type hybrid rice cultivars to further utilize the high-yielding potential of hybrid rice cultivars. The increasing number of spikelets and ideal grain -filling were the direct factors for the high yield of SSCMTS in hybrid rice, and those high-yielding factors relied on high quality seedlings, sturdy individuals, high quality population and vigorous later growth.

  16. 水稻高产创建栽培技术%High Yield and Create Cultivation Techniques of Rice

    Institute of Scientific and Technical Information of China (English)

    姜田英; 彭昌家

    2015-01-01

    This paper introduces the high yield and creates cultivation techniques of rice, such as the selection of seed, timely sowing, soil preparation,fertilization, specification transplanting, reasonable density planting, strengthen the man-agement of the field and timely harvest. To guide farmers to do scientific and reasonable rice super-high-yield strengthen-ing cultivation, improve the yield of rice and increase farmers' income, to ensure the rice production could continue to in-crease and ensure the safety of food production.%介绍了选用良种、适时播种、整好本田、配方施肥、规范移栽,合理密植、加强田间管理和适时收获等水稻高产创建栽培技术,旨在指导农民科学合理做好水稻超高产强化栽培,从而提高水稻单产,增加农民收益,确保水稻总产量持续增加,保障粮食生产安全。

  17. Transcriptome analysis suggests that starch synthesis may proceed via multiple metabolic routes in high yielding potato cultivars.

    Directory of Open Access Journals (Sweden)

    Kacper Piotr Kaminski

    Full Text Available BACKGROUND: Glucose-6-phosphate is imported into the amyloplast of potato tubers and thought to constitute the precursor for starch synthesis in potato tubers. However, recently it was shown that glucose-1-phosphate can also be imported into the amyloplast and incorporated into starch via an ATP independent mechanism under special conditions. Nonetheless, glucose-6-phosphate is believed to be the quantitatively important precursor for starch synthesis in potato. PRINCIPAL FINDING: Potato tubers of the high yielding cv Kuras had low gene expression of plastidial phophoglucomutase (PGM and normal levels of transcripts for other enzymes involved in starch metabolism in comparison with medium and low yielding cultivars as determined by DeepSAGE transcriptome profiling. The decrease in PGM activity in Kuras was confirmed by measuring the enzyme activity from potato tuber extracts. Contrary to expectations, this combination lead to a higher level of intracellular glucose-1-phosphate (G1P in Kuras suggesting that G1P is directly imported into plastids and can be quantitatively important for starch synthesis under normal conditions in high yielding cultivars. SIGNIFICANCE: This could open entirely new possibilities for metabolic engineering of the starch metabolism in potato via the so far uncharacterized G1P transporter. The perspectives are to increase yield and space efficiency of this important crop. In the light of the increasing demands imposed on agriculture to support a growing global population this presents an exciting new possibility.

  18. Effect of combined acetylmethionine, cyanocobalamin and α-lipoic acid on hepatic metabolism in high-yielding dairy cow.

    Science.gov (United States)

    Fiore, Enrico; Perillo, Laura; Piccione, Giuseppe; Gianesella, Matteo; Bedin, Silvia; Armato, Leonardo; Giudice, Elisabetta; Morgante, Massimo

    2016-11-01

    The aim of the study reported in this Research Communication was to investigate the effect of a combined acetylmethionine, cyanocobalamin and α-lipoic acid treatment, on some metabolic parameters of early lactating high-yielding dairy cows. Thirty cows were randomly divided into two groups: experimental group (EG, n = 20) and control group (CG, n = 10). EG received 20 ml of treatment and CG received 20 ml of placebo. The treatments were administered for seven times every 2 d. Blood samples were collected from all cows at 3 time points: 10 ± 2, 30 ± 2 and 50 ± 2 d postpartum. Glucose, β-hydroxybutyrate (BHB), nonesterified fatty acids (NEFA), triglycerides, total cholesterol (TC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamiltransferase (GGT), total bilirubin (TB), conjugated bilirubin (CB), total proteins (TP), globulins, albumin and urea concentrations were determined. Two-way repeated measure analysis of variance was applied. Significant differences in the values of glucose, BHB, NEFA, triglycerides, TC, AST and urea were found between EG and CG. Moreover, the increased glucose, TC, ALT, GGT, TP and globulins, and the reduced BHB, NEFA, AST, triglycerides, TB, CB and urea concentrations were evident in both groups, but the changes were more pronounced in EG. Our findings indicate that our treatment positively influenced liver metabolism in high-yielding dairy cows.

  19. High Yield of GaAs Nanowire Arrays on Si Mediated by the Pinning and Contact Angle of Ga.

    Science.gov (United States)

    Russo-Averchi, Eleonora; Vukajlovic Plestina, Jelena; Tütüncüoglu, Gözde; Matteini, Federico; Dalmau-Mallorquí, Anna; de la Mata, Maria; Rüffer, Daniel; Potts, Heidi A; Arbiol, Jordi; Conesa-Boj, Sonia; Fontcuberta i Morral, Anna

    2015-05-13

    GaAs nanowire arrays on silicon offer great perspectives in the optoelectronics and solar cell industry. To fulfill this potential, gold-free growth in predetermined positions should be achieved. Ga-assisted growth of GaAs nanowires in the form of array has been shown to be challenging and difficult to reproduce. In this work, we provide some of the key elements for obtaining a high yield of GaAs nanowires on patterned Si in a reproducible way: contact angle and pinning of the Ga droplet inside the apertures achieved by the modification of the surface properties of the nanoscale areas exposed to growth. As an example, an amorphous silicon layer between the crystalline substrate and the oxide mask results in a contact angle around 90°, leading to a high yield of vertical nanowires. Another example for tuning the contact angle is anticipated, native oxide with controlled thickness. This work opens new perspectives for the rational and reproducible growth of GaAs nanowire arrays on silicon.

  20. A natural variant of NAL1, selected in high-yield rice breeding programs, pleiotropically increases photosynthesis rate

    Science.gov (United States)

    Takai, Toshiyuki; Adachi, Shunsuke; Taguchi-Shiobara, Fumio; Sanoh-Arai, Yumiko; Iwasawa, Norio; Yoshinaga, Satoshi; Hirose, Sakiko; Taniguchi, Yojiro; Yamanouchi, Utako; Wu, Jianzhong; Matsumoto, Takashi; Sugimoto, Kazuhiko; Kondo, Katsuhiko; Ikka, Takashi; Ando, Tsuyu; Kono, Izumi; Ito, Sachie; Shomura, Ayahiko; Ookawa, Taiichiro; Hirasawa, Tadashi; Yano, Masahiro; Kondo, Motohiko; Yamamoto, Toshio

    2013-01-01

    Improvement of leaf photosynthesis is an important strategy for greater crop productivity. Here we show that the quantitative trait locus GPS (GREEN FOR PHOTOSYNTHESIS) in rice (Oryza sativa L.) controls photosynthesis rate by regulating carboxylation efficiency. Map-based cloning revealed that GPS is identical to NAL1 (NARROW LEAF1), a gene previously reported to control lateral leaf growth. The high-photosynthesis allele of GPS was found to be a partial loss-of-function allele of NAL1. This allele increased mesophyll cell number between vascular bundles, which led to thickened leaves, and it pleiotropically enhanced photosynthesis rate without the detrimental side effects observed in previously identified nal1 mutants, such as dwarf plant stature. Furthermore, pedigree analysis suggested that rice breeders have repeatedly selected the high-photosynthesis allele in high-yield breeding programs. The identification and utilization of NAL1 (GPS) can enhance future high-yield breeding and provides a new strategy for increasing rice productivity. PMID:23985993

  1. Selection and Study of High-yield Aerobic Strains of Treating the Closed Circulation Wastewater for Regenerated Fiber

    Institute of Scientific and Technical Information of China (English)

    MA Yong-wen; FU Yan-fang; WAN Jin-quan

    2007-01-01

    Efficient and reliable removal of cellulose,hemicellulose and lignin,that are the major organic pollutants in the wastewater from regenerated fiber,is critically important to prevent toxicity discharge.Low-and high-pH stresses sometimes occur in the effluent treatment systems due to the use of a large amount of acid and alkaline in the pulping process.Using flat separation method to select high-yield strains from bio-contact oxidation basin,seeing configuration of the strains and doing some physiological experiments,we found that the strains contain two kinds of main bacteria,Zoogloea sp.and Pseudomona sp.We also discovered the best growing time by spectrophotometer.The best growing time is at 0~32h,the logarithmic phase is about at 12~32 h,and the stable growth phase is about 32~60 h.Furthermore,we concluded that the disposal ability of high-yield strain is better than the ordinary one by doing parallel experiment.Through onhogonal test we also confirmed that the best growing temperature and pH value are 29℃ and 7.3 respectively,The COD removal rate is about 93% when the biomembrane is in good condition.

  2. 贵州高产油菜的群体结构特征及高产栽培技术%The Group Structure Characteristics and High-yield Culture Technique of High-yield Rape in Guizhou

    Institute of Scientific and Technical Information of China (English)

    冯文豪; 冯泽蔚; 苏跃

    2012-01-01

    In order to promote the integration and application of high yield cultivation technology of rape,the rape yield and component features in high-yield fields were analyzed in 2010-2011. The results showed that; 1) the group structure characteristics with the yield of over 200 kg/667m2 were as follows; average cultivation density 6 099. 2 plants/667m2 , mean pod number 3. 509 106 per 667 m2, grains per pod 18. 5, 1 000-seed weight 3. 7 g, plant height 191. 4 cm, branch number 10. 9, main inflorescence length 72. 8 cm, average yield 216. 2 kg/667m2. 2) The high-yield cultivation techniques included sowing in September 5-10, cultivating strong seedlings, transplanting on moderate-fertility soil in October 10 ?20, fine preparation of soil, soil testing and formulated fertilization, in time irrigation, disease, pest and grass control.%为了促进贵州油菜高产栽培技术的集成和运用,对2010-2011年参加贵州省油菜高产创建活动的高产田块油菜产量及其群体构成特征进行分析.结果表明:1)产量为200 kg/667m2以上油菜群体的结构特征为平均栽培密度达6 099.2株/667m2,平均角果数3.509×106个/667m2,每果粒数18.5粒,千粒重3.7g,株高191.4 cm,分枝数10.9个,主花序长72.8 cm,平均产量达216.2 kg/667m2.2)高产田块的栽培措施为9月5-10日播种,培育壮苗,10月10-20日移栽,土壤肥力中等,精细整地,测土配方施肥,及时灌排水和防治病虫草害等.

  3. Neutron tomography

    Science.gov (United States)

    Crump, James C., III; Richards, Wade J.; Shields, Kevin C.

    1995-07-01

    The McClellan Nuclear Radiation Center's (MNRC) staff in conjunction with a Cooperative Research and Development Agreement (CRDA) with the U.C. Santa Barbara facility has developed a system that can be used for aircraft inspection of jet engine blades. The problem was to develop an inspection system that can detect very low concentrations of hydrogen (i.e., greater than 100 ppm) in metal matricies. Specifically in Titanium alloy jet engine blades. Entrapment and precipitation of hydrogen in metals is an undesirable phenomenon which occurs in many alloys of steel and titanium. In general, metals suffer a loss of mechanical properties after long exposures to hydrogen, especially at high temperatures and pressures, thereby becoming embrittled. Neutron radiography has been used as a nondestructive testing technique for many years. Neutrons, because of their unique interactions with materials, are especially useful in the detection of hydrogen. They have an extremely high interaction cross section for low atomic number nuclei (i.e., hydrogen). Thus hydrogen in a metal matrix can be visualized using neutrons. Traditional radiography is sensitive to the total attenuation integrated over the path of radiation through the material. Increased sensitivity and quantitative cross section resolution can be obtained using three-dimensional volumetric imaging techniques such as tomography. The solution used to solve the problem was to develop a neutron tomography system. The neutron source is the McClellan Nuclear Radiation Center's 1 MW TRIGA reactor. This paper describes the hardware used in the system as well as some of the preliminary results.

  4. Neutron flux from a 14-MeV neutron generator with tungsten filter for research in NDA methods for nuclear safeguards and security

    Science.gov (United States)

    Rennhofer, H.; Pedersen, B.; Crochemore, J.-M.

    2009-12-01

    The Joint Research Centre has taken into operation a new experimental device designed for research in the fields of nuclear safeguards and security applications. The research projects currently undertaken include detection of shielded contraband materials, detection of fissile materials, and mass determination of small fissile materials in shielded containers. The device, called the Pulsed Neutron Interrogation Test Assembly (PUNITA), incorporates a pulsed 14-MeV (D-T) neutron generator and a large graphite mantle surrounding the sample cavity. By pulsing the neutron generator with a frequency in the range of 10 to 150 Hz, a sample may be interrogated first by fast neutrons and a few hundred micro-seconds later by a pure thermal neutron flux. The permanent detection systems incorporated in PUNITA include 3He neutrons detectors, HPGe gamma detectors, and lanthanum bromide scintillation detectors. We have studied the effects of placing a tungsten liner around the neutron generator target. The 14-MeV neutrons induce (n, 2n) and (n, 3n) reactions. In addition the mean neutron energy emitted from generator/tungsten assembly is reduced to about 1 MeV. Both of these effects increase the thermal neutron flux in the sample cavity. The paper describes the observed advantages of the tungsten liner with respect to increase in thermal flux, and better shielding capabilities of the nearby gamma and neutron detectors.

  5. Overview of Ignitor Neutronics and Activation

    Science.gov (United States)

    Rollet, S.; Batistoni, P.; Forrest, R.

    1999-11-01

    The Ignitor experiment is designed to produce D-T plasmas where ignition can take place and the physics of α-particles can be studied. After a first period of operation without significant neutron production, a second phase in deuterium with 2.5 MeV neutron production rate up to 10^17 n/s is planned. This will be followed by operations at increasing percentages of tritium, leading to short, but intense 14 MeV neutron production, up to ≈ 3 × 10^19 n/s. To calculate the neutron fluxes in all the machine components, including the streaming through the ports, a detailed description of the actual Ignitor machine is implemented in the MCNP-4B Monte Carlo code. These fluxes are then used as input for the FISPACT-97 code for the analysis of the activation at the end of life (EOL) and at intermediate times for safety assessment purposes. The estimated neutron emission pulse results in rather modest neutron fluences (≈ 10^18 n/cm^2 on the first wall at EOL). Therefore, radiation damage in the device components is not a concern, with the possible exception of the toroidal magnet insulator. On the other hand, the neutron flux on the first wall can be as high as that of a demonstration reactor (≈ 10^14 n/s/cm^2), inducing, in the absence of a blanket, considerable activation. The shielding strategy and possible solutions to prevent/reduce the activation of the cryostat are presented.

  6. Unfolding the fast neutron spectra of a BC501A liquid scintillation detector using GRAVEL method

    CERN Document Server

    Chen, Yonghao; Lei, Jiarong; An, Li; Zhang, Xiaodong; Shao, Jianxiong; Zheng, Pu; Wang, Xinhua

    2013-01-01

    Accurate knowledge of the neutron energy spectra is useful in basic research and applications. The overall procedure of measuring and unfolding the fast neutron energy spectra with BC501A liquid scintillation detector is described. The recoil proton spectrum of Am-Be neutrons was obtained experimentally. With the NRESP7 code, the response matrix of detector was simulated. Combining the recoil proton spectrum and response matrix, the unfolding of neutron spectra was performed by GRAVEL iterative algorithm. A MatLab program based on the GRAVEL method was developed. The continuous neutron spectrum of Am-Be source and monoenergetic neutron spectrum of D-T source have been unfolded successfully and are in good agreement with their standard reference spectra. The unfolded Am-Be spectrum are more accurate than the spectra unfolded by artificial neural networks in recent years.

  7. Unfolding the fast neutron spectra of a BC501A liquid scintillation detector using GRAVEL method

    Science.gov (United States)

    Chen, YongHao; Chen, XiMeng; Lei, JiaRong; An, Li; Zhang, XiaoDong; Shao, JianXiong; Zheng, Pu; Wang, XinHua

    2014-10-01

    Accurate knowledge of the neutron energy spectra is useful in basic research and applications. The overall procedure of measuring and unfolding the fast neutron energy spectra with BC501A liquid scintillation detector is described. The recoil proton spectrum of 241Am-Be neutrons was obtained experimentally. With the NRESP7 code, the response matrix of detector was simulated. Combining the recoil proton spectrum and response matrix, the unfolding of neutron spectra was performed by GRAVEL iterative algorithm. A MatLab program based on the GRAVEL method was developed. The continuous neutron spectrum of 241Am-Be source and monoenergetic neutron spectrum of D-T source have been unfolded successfully and are in good agreement with their standard reference spectra. The unfolded 241Am-Be spectrum are more accurate than the spectra unfolded by artificial neural networks in recent years.

  8. Development of high-intensity deuterium-deuterium and deuterium-trittium neutron sources and neutron filters for medical and industrial applications

    Science.gov (United States)

    Verbeke, Jerome Maurice

    This thesis consists of three main parts. The first part is related to boron neutron capture therapy (BNCT), the second part to boron neutron capture synovectomy (BNCS), and the third part to the neutron generator development. A monoenergetic neutron beam simulation study is carried out to determine the most suitable neutron energy for treatment of shallow and deep-seated brain tumors in the context of BNCT. Two figures-of-merit---the absorbed skin dose and the absorbed tumor dose at a given depth in the brain---are used to measure the neutron beam quality. Based on the results of this study, moderators, reflectors and delimiters are designed and optimized to moderate the high-energy neutrons from the fusion reactions D-D and D-T down to a suitable energy spectrum. Two different computational models have been used to study the dose distribution in the brain. A monoenergetic neutron beam simulation study is carried out to determine the optimal neutron energy for treatment of rheumatoid arthritis. Two figures-of-merit are used to measure the neutron beam quality, the ratio of the synovium absorbed dose to the skin absorbed dose, and the ratio of the synovium absorbed dose to the bone absorbed dose. It was found that thermal neutron beams are optimal for treatment. Computation of the dose distribution in the knee requires the simulation of particle transport from the neutron source to the knee phantom through the moderator. The third part describes the development of high-intensity D-D and D-T neutron generators. Thick target neutron yield computations have been performed to estimate the neutron yield of titanium and scandium targets. With an average deuteron beam current of 1 A and an energy of 120 keV, a neutron production of about 1014 n/s can be estimated for a tritiated target. In mixed deuteron/triton beam operation, a beam current of 2 A at 150 keV is required for the same neutron output. Despite this lower neutron production, this mode of operation is

  9. Homogeneity analysis of high yield manufacturing process of mems-based pzt thick film vibrational energy harvesters

    DEFF Research Database (Denmark)

    Lei, Anders; Xu, Ruichao; Pedersen, C.M.

    2011-01-01

    This work presents a high yield wafer scale fabrication of MEMS-based unimorph silicon/PZT thick film vibrational energy harvesters aimed towards vibration sources with peak frequencies in the range of a few hundred Hz. By combining KOH etching with mechanical front side protection, SOI wafer...... to accurately define the thickness of the silicon part of the harvester and a silicon compatible PZT thick film screen-printing technique, we are able to fabricate energy harvesters on wafer scale with a yield higher than 90%. The characterization of the fabricated harvesters is focused towards the full wafer....../mass-production aspect; hence the analysis of uniformity in harvested power and resonant frequency....

  10. Proteomic Analysis of the Response of Liangyoupeijiu (Super High-Yield Hybrid Rice) Seedlings to Cold Stress

    Institute of Scientific and Technical Information of China (English)

    Ping-Fang Yang; Xiao-Juan Li; Yu Liang; Yu-Xiang Jing; Shi-Hua Shen; Ting-Yun Kuang

    2006-01-01

    Liangyoupeijiu is a super high-yield hybrid rice. Despite its advantages with respect to yield and grain quality, it is sensitive to cold, which keeps it from being widely cultivated. We subjected Liangyoupeijiu seedlings to 4 ℃ cold treatment, then extracted the leaf proteins. After 2-D gel electrophoresis separation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, a series of differentially displayed proteins were identified. Some metabolism-associated proteins were found among the downregulated proteins, such as carbamoyl phosphate synthetase, transketolase 1, dihydrolipoamide dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase. The upregulated proteins included both stress-resistance proteins such as nucleoside diphosphate kinase Ⅰ and proteins that are negative for rice growth, such as FtsH-like protein, plastid fusion and/or translocation factor (Pftf) and actin. Our results indicate that cold may inhibit Liangyoupeijiu growth through decreasing metabolic activity and damaging cell structure.

  11. Powder, paper and foam of few-layer graphene prepared in high yield by electrochemical intercalation exfoliation of expanded graphite.

    Science.gov (United States)

    Wu, Liqiong; Li, Weiwei; Li, Peng; Liao, Shutian; Qiu, Shengqiang; Chen, Mingliang; Guo, Yufen; Li, Qi; Zhu, Chao; Liu, Liwei

    2014-04-09

    A facile and high-yield approach to the preparation of few-layer graphene (FLG) by electrochemical intercalation exfoliation (EIE) of expanded graphite in sulfuric acid electrolyte is reported. Stage-1 H2SO4-graphite intercalation compound is used as a key intermediate in EIE to realize the efficient exfoliation. The yield of the FLG sheets (graphene structures. Flexible and freestanding graphene papers made of the FLG flakes retain excellent conductivity (≈24,500 S m(-1)). Three-dimensional (3D) graphene foams with light weight are fabricated from the FLG flakes by the use of Ni foams as self-sacrifice templates. Furthermore, 3D graphene/Ni foams without any binders, which are used as supercapacitor electrodes in aqueous electrolyte, provide the specific capacitance of 113.2 F g(-1) at a current density of 0.5 A g(-1), retaining 90% capacitance after 1000 cycles.

  12. Continuous high-yield production of vertically aligned carbon nanotubes on 2D and 3D substrates.

    Science.gov (United States)

    Guzmán de Villoria, Roberto; Hart, A John; Wardle, Brian L

    2011-06-28

    Vertically aligned carbon nanotubes (VACNTs) have certain advantages over bulk CNT powders and randomly oriented CNT mats for applications in flexible electronic devices, filtration membranes, biosensors and multifunctional aerospace materials. Here, a machine and a process to synthesize VACNTs in a continuous manner are presented showing uniform growth on 2D and 3D substrates, including alumina fibers, silicon wafer pieces, and stainless steel foils. Aligned multiwalled carbon nanotubes (MWNT) are synthesized at substrate feed rates of up to 6.8 cm/min, and the CNTs reach up to 60 μm in length depending on residence time in the reactor. In addition to the aligned morphology indicative of high yield growth, transmission electron microscopy and Raman spectroscopy reveal that the CNTs are of comparable quality to CNTs grown via a similar batch process. A significant reduction in time, reaction products, gases, and energy is demonstrated relative to batch processing, paving the way for industrial production of VACNTs.

  13. High-Yield Excited Triplet States in Pentacene Self-Assembled Monolayers on Gold Nanoparticles through Singlet Exciton Fission.

    Science.gov (United States)

    Kato, Daiki; Sakai, Hayato; Tkachenko, Nikolai V; Hasobe, Taku

    2016-04-18

    One of the major drawbacks of organic-dye-modified self-assembled monolayers on metal nanoparticles when employed for efficient use of light energy is the fact that singlet excited states on dye molecules can be easily deactivated by means of energy transfer to the metal surface. In this study, a series of 6,13-bis(triisopropylsilylethynyl)pentacene-alkanethiolate monolayer protected gold nanoparticles with different particle sizes and alkane chain lengths were successfully synthesized and were employed for the efficient generation of excited triplet states of the pentacene derivatives by singlet fission. Time-resolved transient absorption measurements revealed the formation of excited triplet states in high yield (172±26 %) by suppressing energy transfer to the gold surface.

  14. High-yield production of extracellular type-I cellulose by the cyanobacterium Synechococcus sp. PCC 7002.

    Science.gov (United States)

    Zhao, Chi; Li, Zhongkui; Li, Tao; Zhang, Yingjiao; Bryant, Donald A; Zhao, Jindong

    2015-01-01

    Cellulose synthase, encoded by the cesA gene, is responsible for the synthesis of cellulose in nature. We show that the cell wall of the cyanobacterium Synechococcus sp. PCC 7002 naturally contains cellulose. Cellulose occurs as a possibly laminated layer between the inner and outer membrane, as well as being an important component of the extracellular glycocalyx in this cyanobacterium. Overexpression of six genes, cmc-ccp-cesAB-cesC-cesD-bgl, from Gluconacetobacter xylinus in Synechococcus sp. PCC 7002 resulted in very high-yield production of extracellular type-I cellulose. High-level cellulose production only occurred when the native cesA gene was inactivated and when cells were grown at low salinity. This system provides a method for the production of lignin-free cellulose from sunlight and CO2 for biofuel production and other biotechnological applications.

  15. Studies on Mutation Breeding of High-Yielding Xylanase Strains by Low-Energy Ion Beam Implantation

    Institute of Scientific and Technical Information of China (English)

    LI Shichang; YAO Jianming; YU Zhengling

    2007-01-01

    As a new mutagenetic method,low-energy ion implantation has been used widely in many research areas in recent years.In order to obtain some industrial strains with high xylanase yield,the wild type strain Aspergillus niger A3 was mutated by means of nitrogen ions implantation (10 keV,2.6 × 1014~1.56 × 1015 ions/cm2) and a mutant N212 was isolated subsequently.However,it was found that the initial screening means of the high-yielding xylanase strains such as transparent halos was unfit for first screening.Compared with that of the wild type strain,xylanase production of the mutant N212 was increased from 320 IU/ml to 610 IU/ml,and the optimum fermentation temperature was increased from 28 ℃ to 30 ℃.

  16. High yield synthesis of Ni-BTC metal-organic framework with ultrasonic irradiation: Role of polar aprotic DMF solvent.

    Science.gov (United States)

    Israr, Farrukh; Chun, Daye; Kim, Yeongmin; Kim, Duk Kyung

    2016-07-01

    Nickel based porous solid was synthesized with 20 kHz ultrasonic irradiation. The reaction of Ni(II) nitrate hexahydrate with 1,3,5-benzene tricarboxylic acid in N,N-Dimethylformamide (DMF) as the sole solvent under ultrasonic radiation produced porous Ni-BTC MOF. Choice of correct solvent for the ultrasonic treatment was proven important. The effect of varying ultrasonic powers (40%, 60% and 80% of 750 W) along with different temperature conditions (50 °C, 60 °C, 70 °C and 80 °C) influenced the respective yield. A very high yield of 88% Ni-BTC MOF was obtained from 80% ultrasonic power at 60 °C. BET surface areas of the MOF crystals measured by N2 gas adsorption isotherms were in the range of 960-1000 m(2)/g.

  17. Cloning and selection of carotenoid ketolase genes for the engineering of high-yield astaxanthin in plants.

    Science.gov (United States)

    Huang, Junchao; Zhong, Yujuan; Sandmann, Gerhard; Liu, Jin; Chen, Feng

    2012-08-01

    β-Carotene ketolase (BKT) catalyzes the rate-limiting steps for the biosynthesis of astaxanthin. Several bkt genes have been isolated and explored to modify plant carotenoids to astaxanthin with limited success. In this study, five algal BKT cDNAs were isolated and characterized for the engineering of high-yield astaxanthin in plants. The products of the cDNAs showed high similarity in sequence and enzymatic activity of converting β-carotene into canthaxanthin. However, the enzymes exhibited extremely different activities in converting zeaxanthin into astaxanthin. Chlamydomonas reinhardtii BKT showed the highest conversion rate (ca 85%), whereas, Neochloris wimmeri BKT exhibited very poor activity of ketolating zeaxanthin. Expression of C. reinhardtii BKT in tobacco led to a twofold increase of total carotenoids in the leaves with astaxanthin being the predominant. The bkt genes described here provide a valuable resource for metabolic engineering of plants as cell factories for astaxanthin production.

  18. The Relationship Among Photoinhibition, Photooxidation and Early Aging at a Late Development Stage in Different Varieties with High Yield

    Institute of Scientific and Technical Information of China (English)

    JIAO De-mao; LI Xia; HUANG Xue-qing; JI Ben-hua

    2002-01-01

    Using six high yield varieties from different ecological districts in China the parameters of Chl fluorescence, the performance of membrane lipid peroxidation and the reduction of Chl content in flag leaf under natural condition at the later developmental stages (from heading stage to mature stage). The results showed that Fv/Fm, decreased gradually, the excessive light energy led to the accumulation of active oxygen O2-, H2O2 and the product of membrane-lipid peroxidation, MDA, which resulted in the reduction of Chl content and early aging due to photooxidation during the course of senescence of flag leaf. This phenomenon varied obviously in rice varieties. When comparina japonica tolerant to photooxidation, Fv/Fm in indica shanyou 63 susceptible to photoxidation decreased significantly. An increase of active oxygen and a sharp drop of Chl content, resulted in "yellowish" early aging and influenced filling and setting of rice grain. The mechanism on early aging in indica was related to light and temperature conditions in filling stages. On a fine day (above 25℃ ), PS Ⅱ reaction center exhibited a dynamic change on revisable inactivation. Under strong midday light, PS Ⅱ function in indica exhibited obvious down-regulation and photoinhibition; Under strong light with low temperature, PS Ⅱ resulted in photodamage, showing early aging, which were related to the degradation of PS Ⅱ - D1 Protein and the inhibition of the endogenous protecting system such as Xanthophyll cycle and the enzymes of scavenging active oxygen. The results suggested that for a view of high-yield breeding, on the basis of a good type-plant, giving consideration to the utilization of heterosis and resistance to early aging, selecting japonica or a sterile line with japonice genotype as maternal was a breeding strategy worthy of being paid more attention.

  19. Neutron reflectometry

    DEFF Research Database (Denmark)

    Klösgen-Buchkremer, Beate Maria

    2014-01-01

    to hundreds of nanometers. Thickness resolution for flat surfaces is in the range of few Ǻngstrøm, and as a peculiar benefit, the presence and properties of buried interfaces are accessible. Focus here will be on neutron reflectometry, a technique that is unique in applications involving composite organic...... of desired information. In the course, an introduction into the method and an overview on selected instruments at large scale facilities will be presented. Examples will be given that illustrate the potential of the method, mostly based on organic films. Results from the investigation of layered films...... and the detection on nanoscopic roughnesses will be shown. The potential of neutron reflectometry is not only of academic origin. It may turn out to be useful in the design and development of new functional materials even though it will never develop into a standard method to be applied in the product control...

  20. Study of sup 1 sup 2 sup 1 Te with the (d,t) reaction

    CERN Document Server

    Bucurescu, D; Wirth, H F; Marginean, N; Köster, U; Schauer, W; Tomandl, I; Graw, G; Metz, A; Hertenberger, R; Eisermann, Y

    2000-01-01

    The structure of the sup 1 sup 2 sup 1 Te nucleus has been studied with the sup 1 sup 2 sup 2 Te(d,t) reaction at E sub d =24.0 MeV. About 100 excited states have been observed up to an excitation energy of 2.65 MeV, and for most of them spin and parity values are proposed. A theoretical analysis based on the Interacting Boson-Fermion Model-1 is presented for the whole isotopic chain from sup 1 sup 1 sup 9 Te to sup 1 sup 2 sup 9 Te. The evolution of both positive and negative parity low-lying levels in these nuclei is reasonably well described with an essentially constant boson-fermion interaction. A detailed comparison of the calculations with experimental data is presented for sup 1 sup 2 sup 1 Te. The level scheme up to about 1.5 MeV excitation is reasonably well accounted for. Possible indications of states with 'intruder' character are discussed.

  1. D-T burning plasma characteristics in an A=2 tokamak reactor

    Institute of Scientific and Technical Information of China (English)

    石秉仁

    2005-01-01

    The deuterium-tritium (D-T) burning plasma characteristic in an aspect ratio A=2 tokamak reactor is studied based on a simple equilibrium configuration, the Soloviev-type configuration. Operation limits for the Troyon beta value and for the Greenwald density value as well as for the ITER H-mode confinement scaling are used as the benchmark.It is found that in addition to suitable elongation, large triangularity has advantage for arriving at high beta value and obtaining high fusion power output. Compared to the present ITER design, the A=2 system can have very good merit for the avoidance of disruptions by setting rather high edge q value while keeping relatively large total toroidal current.The main disadvantage of decreasing the aspect ratio is due to the loss of more useful space in the inward region that leads to the decrease of toroidal magnetic field in the plasma region, then worsening the fusion merit. Our analysis and calculation also present a trade-off in this respect. Due to simple equilibrium configuration assumed, some other important issues such as the bootstrap current alignment cannot be optimized. However, the present analysis can offer an insight into the advantages of the medium aspect ratio reactor system that is a blank in present-day tokamak study.

  2. Aortic valve and ascending aortic root modeling from 3D and 3D+t CT

    Science.gov (United States)

    Grbic, Saša; Ionasec, Razvan I.; Zäuner, Dominik; Zheng, Yefeng; Georgescu, Bogdan; Comaniciu, Dorin

    2010-02-01

    Aortic valve disorders are the most frequent form of valvular heart disorders (VHD) affecting nearly 3% of the global population. A large fraction among them are aortic root diseases, such as aortic root aneurysm, often requiring surgical procedures (valve-sparing) as a treatment. Visual non-invasive assessment techniques could assist during pre-selection of adequate patients, planning procedures and afterward evaluation of the same. However state of the art approaches try to model a rather short part of the aortic root, insufficient to assist the physician during intervention planning. In this paper we propose a novel approach for morphological and functional quantification of both the aortic valve and the ascending aortic root. A novel physiological shape model is introduced, consisting of the aortic valve root, leaflets and the ascending aortic root. The model parameters are hierarchically estimated using robust and fast learning-based methods. Experiments performed on 63 CT sequences (630 Volumes) and 20 single phase CT volumes demonstrated an accuracy of 1.45mm and an performance of 30 seconds (3D+t) for this approach. To the best of our knowledge this is the first time a complete model of the aortic valve (including leaflets) and the ascending aortic root, estimated from CT, has been proposed.

  3. Ligation of double-stranded and single-stranded [Oligo(dT)] DNA by vaccinia virus DNA ligase

    OpenAIRE

    1996-01-01

    Vaccinia virus DNA ligase has been expressed in Escherichia coli, purified, and biochemically characterized. The enzyme ligates double-stranded (ds) DNA substrates with either cohesive or blunt-end termini and the latter reaction is stimulated by PEG. Vaccinia virus DNA ligase can also ligate oligo(dT) when annealed to either a poly(dA) or a poly(rA) backbone and, remarkably, free oligo(dT). This ligation of a single-stranded (ss) substrate is unique among eukaryotic DNA ligases. The enzyme r...

  4. Spallation Neutron Source (SNS)

    Data.gov (United States)

    Federal Laboratory Consortium — The SNS at Oak Ridge National Laboratory is a next-generation spallation neutron source for neutron scattering that is currently the most powerful neutron source in...

  5. Evaluation of two-stage system for neutron measurement aiming at increase in count rate at Japan Atomic Energy Agency-Fusion Neutronics Source

    Energy Technology Data Exchange (ETDEWEB)

    Shinohara, K., E-mail: shinohara.koji@jaea.go.jp; Ochiai, K.; Sukegawa, A. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Ishii, K.; Kitajima, S. [Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, Miyagi 980-8579 (Japan); Baba, M. [Cyclotron and Radioisotope Center, Tohoku University, Sendai, Miyagi 980-8578 (Japan); Sasao, M. [Organization for Research Initiatives and Development, Doshisha University, Kyoto 602-8580 (Japan)

    2014-11-15

    In order to increase the count rate capability of a neutron detection system as a whole, we propose a multi-stage neutron detection system. Experiments to test the effectiveness of this concept were carried out on Fusion Neutronics Source. Comparing four configurations of alignment, it was found that the influence of an anterior stage on a posterior stage was negligible for the pulse height distribution. The two-stage system using 25 mm thickness scintillator was about 1.65 times the count rate capability of a single detector system for d-D neutrons and was about 1.8 times the count rate capability for d-T neutrons. The results suggested that the concept of a multi-stage detection system will work in practice.

  6. Neutron scattering. Lectures

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2010-07-01

    The following topics are dealt with: Neutron sources, neutron properties and elastic scattering, correlation functions measured by scattering experiments, symmetry of crystals, applications of neutron scattering, polarized-neutron scattering and polarization analysis, structural analysis, magnetic and lattice excitation studied by inelastic neutron scattering, macromolecules and self-assembly, dynamics of macromolecules, correlated electrons in complex transition-metal oxides, surfaces, interfaces, and thin films investigated by neutron reflectometry, nanomagnetism. (HSI)

  7. Netropsin . dG-dG-dA-dA-dT-dT-dC-dC complex. Antibiotic binding at adenine . thymine base pairs in the minor groove of the self-complementary octanucleotide duplex.

    Science.gov (United States)

    Patel, D J

    1979-09-01

    The structure of the netropsin . dG-dG-dA-dA-dT-dT-dC-dC complex (one antibiotic molecule/self-complementary octanucleodide duplex) and its dynamics as a function of temperature have been monitored by the nuclear magnetic resonances of the Watson-Crick protons, the nonexchangeable base and sugar protons and the backbone phosphates. The antibiotic forms a complex with the nucleic acid duplex at the dA . dT-containing tetranucleotide segment dA-dA-dT-dT, with slow migration amongst potential binding sites at low temperature. The downfield shifts in the exchangeable protons of netropsin on complex formation demonstrate the contributions of hydrogen-bonding interactions between the antibiotic and the nucleic acid to the stability of the complex. Complex formation results in changes in the glycosidic torsion angles of both thymidine residues and one deoxyadenosine residue as monitored by chemical shift changes in the thymine C-6 and adenine C-8 protons. The close proximity of the pyrrole rings of the antibiotic and the base-pair edges in the minor groove is manifested in the downfield shifts (0.3--0.5 ppm) of the pyrrole C-3 protons of netropsin and one adenine C-2 proton and one thymine N-3 base-pair proton on complex formation. The internucleotide phosphates of the octanucleotide undergo 31P chemical shift changes on addition of netropsin and these may reflect, in part, contributions from electrostatic interactions between the charged ends of the antibiotic and the backbone phosphates of the nucleic acid.

  8. Portable Neutron Generator with 9-Section Silicon $\\alpha $-Detector

    CERN Document Server

    Bystritsky, V M; Kadyshevskij, V G; Khasaev, T O; Kobzev, A P; Presnyakov, Yu K; Rogov,Yu N; Ryzhkov, V I; Sapozhnikov, M G; Sissakian, A N; Slepnev, V M; Zamyatin, N I

    2006-01-01

    The characteristics of the portable neutron generator with a built-in $\\alpha $-detector are presented. Based on the "tagged" neutron method (TNM) the generator ~is being used for identification of ~the hidden chemical compounds. One of the special features of such generators compared to generators traditionally used and produced in industry is that the generator is a source of monoenergetic "tagged" 14.1 MeV neutrons produced in the binary nuclear reaction $d+t \\to \\alpha $ (3.5 MeV) $+n$ (14.1~MeV). Unambiguous information about the time and direction of the neutron emitted from the target can be obtained by recording an $\\alpha $ particle by the multi-pixel $\\alpha $-detector placed inside the neutron tube. The study of the "tagged" neutron method (TNM) shows that the use of the ($\\alpha $--$\\gamma $) coincidence reduces the gamma background induced by scattered neutrons by a factor of more than 200, which allows the detection and identification of small quantities of explosives, drugs, and toxic agents. T...

  9. Compact, energy EFFICIENT neutron source: enabling technology for various applications

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, A.; Roser, T.

    2009-12-01

    A novel neutron source comprising of a deuterium beam (energy of about 100 KeV) injected into a tube filled with tritium gas and/or tritium plasma that generates D-T fusion reactions, whose products are 14.06 MeV neutrons and 3.52 MeV alpha particles, is described. At the opposite end of the tube, the energy of deuterium ions that did not interact is recovered. Beryllium walls of proper thickness can be utilized to absorb 14 MeV neutrons and release 2-3 low energy neutrons. Each ion source and tube forms a module. Larger systems can be formed from multiple units. Unlike currently proposed methods, where accelerator-based neutron sources are very expensive, large, and require large amounts of power for operation, this neutron source is compact, inexpensive, easy to test and to scale up. Among possible applications for this neutron source concept are sub-critical nuclear breeder reactors and transmutation of radioactive waste.

  10. Analysis for Radiation and Shielding Dose in Plasma Focus Neutron Source Using FLUKA

    Science.gov (United States)

    Nemati, M. J.; Amrollahi, R.; Habibi, M.

    2012-06-01

    Monte Carlo simulations have been performed for the attenuation of neutron radiation produced at Plasma focus (PF) devices through various shielding design. At the test site it will be fired with deuterium and tritium (D-T) fusion resulting in a yield of about 1013 fusion neutrons of 14 MeV. This poses a radiological hazard to scientists and personnel operating the device. The goal of this paper was to evaluate various shielding options under consideration for the PF operating with D-T fusion. Shields of varying neutrons-shielding effectiveness were investigated using concrete, polyethylene, paraffin and borated materials. The most effective shield, a labyrinth structure, allowed almost 1,176 shots per year while keeping personnel under 20 mSV of dose. The most expensive shield that used, square shield with 100 cm concrete thickness on the walls and Borated paraffin along with borated polyethylene added outside the concrete allowed almost 15,000 shot per year.

  11. Neutron Therapy Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Neutron Therapy Facility provides a moderate intensity, broad energy spectrum neutron beam that can be used for short term irradiations for radiobiology (cells)...

  12. Evaluation of Residues of D.D.T and D.D.A in Fish Collected from Caspian Sea, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Shokrzadeh lamuki

    2012-11-01

    Full Text Available Background: Pesticides are essential in modern agricultural practices but due to their biocide activity and potential risk to the consumer, the control of pesticide residues in foods is a growing source of concern for the general population. Extensive application of such agents as organochlorine pesticides in farmlands and contemporary agricultural industries has led to undesired environmental contamination and human health hazards. Thus, this study attempted to evaluate and analyze the residual values of the organochlorine insecticide D.D.T and its metabolite D.D.A in the four species of most consumed fish collected from the Caspian Sea. Methods: In this investigation, concentrations of residual values of D.D.T and D.D.A were quantitatively determined in the 4 species of fish sampled from 4 major fishing centers (Chalous and Babolsar cities and Khazar Abad and Miankaleh regions in Mazandaran province, Iran, using gas chromatography electron-capture detection (GC–ECD in 2008. Results: The results showed that the highest values of D.D.T were in Mugil auratns (0.033±0.008 mg/kg and Rutilus frisikutum (0.031±0.007 mg/kg fishes collected from Babolsar sampling center. Conclusion: Concentrations of D.D.T and D.D.A in the fish were found to be less than the standard permissible intake.

  13. Nonrigid registration of dynamic medical imaging data using nD + t B-splines and a groupwise optimization approach.

    Science.gov (United States)

    Metz, C T; Klein, S; Schaap, M; van Walsum, T; Niessen, W J

    2011-04-01

    A registration method for motion estimation in dynamic medical imaging data is proposed. Registration is performed directly on the dynamic image, thus avoiding a bias towards a specifically chosen reference time point. Both spatial and temporal smoothness of the transformations are taken into account. Optionally, cyclic motion can be imposed, which can be useful for visualization (viewing the segmentation sequentially) or model building purposes. The method is based on a 3D (2D+time) or 4D (3D+time) free-form B-spline deformation model, a similarity metric that minimizes the intensity variances over time and constrained optimization using a stochastic gradient descent method with adaptive step size estimation. The method was quantitatively compared with existing registration techniques on synthetic data and 3D+t computed tomography data of the lungs. This showed subvoxel accuracy while delivering smooth transformations, and high consistency of the registration results. Furthermore, the accuracy of semi-automatic derivation of left ventricular volume curves from 3D+t computed tomography angiography data of the heart was evaluated. On average, the deviation from the curves derived from the manual annotations was approximately 3%. The potential of the method for other imaging modalities was shown on 2D+t ultrasound and 2D+t magnetic resonance images. The software is publicly available as an extension to the registration package elastix. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. High dno/dT liquid crystals and their applications in a thermally tunable liquid crystal photonic crystal fiber

    DEFF Research Database (Denmark)

    Li, J.; Gauza, S.; Wu, S.-T.

    2006-01-01

    crystal mixtures, designated as UCF-1 and UCF-2. The dn(o)/dT of UCF-1 is similar to 4x higher than that of 5CB at room temperature. By infiltrating UCF-1 into the air holes of a three-rod core photonic crystal fiber, we demonstrate a thermally tunable photonic bandgap fiber with tuning sensitivity of 27...

  15. A Low-cost, High-yield Process for the Direct Productin of High Energy Density Liquid Fuel from Biomass

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Rakesh

    2014-02-21

    The primary objective and outcome of this project was the development and validation of a novel, low-cost, high-pressure fast-hydropyrolysis/hydrodeoxygenation (HDO) process (H{sub 2}Bioil) using supplementary hydrogen (H{sub 2}) to produce liquid hydrocarbons from biomass. The research efforts under the various tasks of the project have culminated in the first experimental demonstration of the H2Bioil process, producing 100% deoxygenated >C4+ hydrocarbons containing 36-40% of the carbon in the feed of pyrolysis products from biomass. The demonstrated H{sub 2}Bioil process technology (i.e. reactor, catalyst, and downstream product recovery) is scalable to a commercial level and is estimated to be economically competitive for the cases when supplementary H{sub 2} is sourced from coal, natural gas, or nuclear. Additionally, energy systems modeling has revealed several process integration options based on the H{sub 2}Bioil process for energy and carbon efficient liquid fuel production. All project tasks and milestones were completed or exceeded. Novel, commercially-scalable, high-pressure reactors for both fast-hydropyrolysis and hydrodeoxygenation were constructed, completing Task A. These reactors were capable of operation under a wide-range of conditions; enabling process studies that lead to identification of optimum process conditions. Model compounds representing biomass pyrolysis products were studied, completing Task B. These studies were critical in identifying and developing HDO catalysts to target specific oxygen functional groups. These process and model compound catalyst studies enabled identification of catalysts that achieved 100% deoxygenation of the real biomass feedstock, sorghum, to form hydrocarbons in high yields as part of Task C. The work completed during this grant has identified and validated the novel and commercially scalable H2Bioil process for production of hydrocarbon fuels from biomass. Studies on model compounds as well as real biomass

  16. Determination of NABE in urine of high-yield dairy cows in early lactation in conditions of moderate heat stress

    Directory of Open Access Journals (Sweden)

    Fratrić Natalija

    2010-01-01

    Full Text Available The work presents the results of investigations of the effect of moderate heat stress on the acidobasal status in high-yield dairy cows in early lactation. Improving performance in high-yield dairy cows increases their inclination toward metabolic disorders. The most likely to be affected is the acid-base balance, in particular when cows are exposed to heat stress. Investigations so far have shown that the taking of urine samples and their analysis is the best and fastest way to diagnose disorders in the acid-base balance. Investigations were carried out on 7 clinically healthy cows of the Holstein- Friesian breed in the phase of early lactation, 30 to 40 days (on days 30, 33 and 40 following calving during the summer period, during the month of July, when there were significant variations in daily and nightly temperatures. The cows were in the second and fourth lactation, the annual milk yield was 8000 L milk per cow. The average daily milk production in the early phase of lactation ranged from 35 to 40 L. The cows were fed mixed rations (TMR twice daily. Lucerne hay in limited quantities was given to the cows prior to the mixed feed ration. The ration for this animal category was optimized on the grounds of the daily milk production. The balance of cations and anions in the feed ration stood at 95 mEq/kg DM. The results clearly demonstrate the cows' response to moderate heat stress through the defense parameters in urine (urine pH, NABE (net-acid-base-excretion, acids, bases, ammonium ion (NH4. The determination of the kidney NABE yields more correct data than the urine pH on acidotic conditions. The results of examinations of the urine pH do not show any digressions from physiological values and are approximately the same in all cows during the investigated periods. Normal NABE values are from 100-200 mmol/L. Burdening with acid products results in a NABE range from 0-100mmol/L, and metabolic acidosis results in NAB<0 mmol/L. NABE in the cows

  17. Comparison of ESWAN, SWI-SPGR, and 2D T2*-weighted GRE sequence for depicting cerebral microbleeds.

    Science.gov (United States)

    Guo, L F; Wang, G; Zhu, X Y; Liu, C; Cui, L

    2013-06-01

    We aimed to compare images obtained with an Enhanced 3D multi-echo GRE T2*-weighted angiography (ESWAN) sequence with those obtained with a susceptibility-weighted imaging-spoiled gradient-recalled echo (SWI-SPGR) sequence and a two-dimensional (2D) T2*-weighted gradient-recalled echo (GRE) sequence for the description of cerebral microbleeds (CMBs) in hypertensive patients (elderly people). A total of 273 elderly hypertensive patients were imaged in a 3.0-T MR scanner using ESWAN, SWI-SPGR, and 2D T2*-weighted GRE sequence, respectively. The presence, number, and location of CMBs and scanning and postprocessing time were recorded for both sequences, and the differences were tested using nonparametric McNemar and Friedman tests. CMBs were detected by 2D T2*-weighted GRE images in 54 participants, SWI-SPGR images in 83 participants, and ESWAN images in 88 participants. The participants with CMBs detected by 2D T2*-weighted GRE sequence were fewer than those with CMBs detected by SWI-SPGR or ESWAN sequences (P CMBs in number (P > 0.05). Among the participants with CMBs visualized in both sequences, most patients had CMBs in the subcortical white matter and at deep locations. The participants who had CMBs in the infratentorial region were fewer. The acquisition time of ESWAN images was slightly longer than that of SWI-SPGR images. ESWAN sequence was not superior to SWI-SPGR sequence in depicting CMBs at 3.0-T MR, but both of these sequences were superior to 2D T2*-weighted GRE sequence.

  18. In-situ soil composition and moisture measurement by surface neutron activation analysis

    Science.gov (United States)

    Waring, C.; Smith, C.; Marks, A.

    2009-04-01

    Neutron activation analysis is widely known as a laboratory technique dependent upon a nuclear reactor to provide the neutron flux and capable of precise elemental analysis. Less well known in-situ geochemical analysis is possible with isotopic (252Cf & 241Am) or compact accelerator (D-T, D-D fusion reaction) neutron sources. Prompt gamma neutron activation analysis (PGNAA) geophysical borehole logging has been applied to mining issues for >15 years (CSIRO) using isotopic neutron sources and more recently to environmental and hydro-geological applications by ANSTO. Similarly, sophisticated geophysical borehole logging equipment based on inelastic neutron scattering (INS) has been applied in the oil and gas industry by large oilfield services companies to measure oil saturation indices (carbon/oxygen) using accelerator neutron sources. Recent advances in scintillation detector spectral performance has enabled improved precision and detection limits for elements likely to be present in soil profiles (H, Si, Al, Fe, Cl) and possible detection of many minor to trace elements if sufficiently abundant (Na, K, Mg, Ca, S, N, + ). To measure carbon an accelerator neutron source is required to provide fast neutrons above 4.8 MeV. CSIRO and ANSTO propose building a soil geochemical analysis system based on experience gained from building and applying PGNA borehole logging equipment. A soil geochemical analysis system could effectively map the 2D geochemical composition of the top 50cm of soil by dragging the 1D logging equipment across the ground surface. Substituting an isotopic neutron source for a D-T accelerator neutron source would enable the additional measurement of elemental carbon. Many potential ambiguities with other geophysical proxies for soil moisture may be resolved by direct geochemical measurement of H. Many other applications may be possible including time series in-situ measurements of soil moisture for differential drainage, hydrology, land surface

  19. A cDNA Clone-Launched Platform for High-Yield Production of Inactivated Zika Vaccine

    Directory of Open Access Journals (Sweden)

    Yujiao Yang

    2017-03-01

    Full Text Available A purified inactivated vaccine (PIV using the Zika virus (ZIKV Puerto Rico strain PRVABC59 showed efficacy in monkeys, and is currently in a phase I clinical trial. High-yield manufacture of this PIV is essential for its development and vaccine access. Here we report an infectious cDNA clone-launched platform to maximize its yield. A single NS1 protein substitution (K265E was identified to increase ZIKV replication on Vero cells (a cell line approved for vaccine production for both Cambodian FSS13025 and Puerto Rico PRVABC59 strains. The NS1 mutation did not affect viral RNA synthesis, but significantly increased virion assembly through an increased interaction between NS1 and NS2A (a known regulator of flavivirus assembly. The NS1 mutant virus retained wild-type virulence in the A129 mouse model, but decreased its competence to infect Aedes aegypti mosquitoes. To further increase virus yield, we constructed an infectious cDNA clone of the clinical trial PIV strain PRVABC59 containing three viral replication-enhancing mutations (NS1 K265E, prM H83R, and NS3 S356F. The mutant cDNA clone produced >25-fold more ZIKV than the wild-type parent on Vero cells. This cDNA clone-launched manufacture platform has the advantages of higher virus yield, shortened manufacture time, and minimized chance of contamination.

  20. A Modular Method for the High-Yield Synthesis of Site-Specific Protein-Polymer Therapeutics.

    Science.gov (United States)

    Pang, Yan; Liu, Jinyao; Qi, Yizhi; Li, Xinghai; Chilkoti, Ashutosh

    2016-08-22

    A versatile method is described to engineer precisely defined protein/peptide-polymer therapeutics by a modular approach that consists of three steps: 1) fusion of a protein/peptide of interest with an elastin-like polypeptide that enables facile purification and high yields; 2) installation of a clickable group at the C terminus of the recombinant protein/peptide with almost complete conversion by enzyme-mediated ligation; and 3) attachment of a polymer by a click reaction with near-quantitative conversion. We demonstrate that this modular approach is applicable to various protein/peptide drugs and used it to conjugate them to structurally diverse water-soluble polymers that prolong the plasma circulation duration of these proteins. The protein/peptide-polymer conjugates exhibited significantly improved pharmacokinetics and therapeutic effects over the native protein/peptide upon administration to mice. The studies reported here provide a facile method for the synthesis of protein/peptide-polymer conjugates for therapeutic use and other applications.

  1. Biosynthesis of high yield fatty acids from Chlorella vulgaris NIES-227 under nitrogen starvation stress during heterotrophic cultivation.

    Science.gov (United States)

    Shen, Xiao-Fei; Chu, Fei-Fei; Lam, Paul K S; Zeng, Raymond J

    2015-09-15

    In this study the heterotrophic cultivation of Chlorella vulgaris NIES-227 fed with glucose was investigated systematically using six media types; combinations of nitrogen repletion/depletion and phosphorus repletion/limitation/depletion. It was found that a high yield of fatty acids (0.88 of fed glucose-COD) and a high content of fatty acid methyl esters (FAMEs) (89% of dry weight) were obtained under nitrogen starved conditions. To our knowledge it is the first report on such high COD conversion yield and FAME content in microalgae. The dominant fatty acid (>50%) was methyl oleate (C18:1), a desirable component for biodiesel synthesis. FAME content under nitrogen starved conditions was significantly higher than under nitrogen sufficient conditions, while phosphorus had no significant influence, indicating that nitrogen starvation was the real "fatty acids trigger" in heterotrophic cultivation. These findings could simplify the downstream extraction process, such as the extrusion of oil from soybeans, and could reduce operating costs by improving the fatty acid yield from waste COD.

  2. High-throughput and high-yield fabrication of uniaxially-aligned chitosan-based nanofibers by centrifugal electrospinning.

    Science.gov (United States)

    Erickson, Ariane E; Edmondson, Dennis; Chang, Fei-Chien; Wood, Dave; Gong, Alex; Levengood, Sheeny Lan; Zhang, Miqin

    2015-12-10

    The inability to produce large quantities of nanofibers has been a primary obstacle in advancement and commercialization of electrospinning technologies, especially when aligned nanofibers are desired. Here, we present a high-throughput centrifugal electrospinning (HTP-CES) system capable of producing a large number of highly-aligned nanofiber samples with high-yield and tunable diameters. The versatility of the design was revealed when bead-less nanofibers were produced from copolymer chitosan/polycaprolactone (C-PCL) solutions despite variations in polymer blend composition or spinneret needle gauge. Compared to conventional electrospinning techniques, fibers spun with the HTP-CES not only exhibited superior alignment, but also better diameter uniformity. Nanofiber alignment was quantified using Fast Fourier Transform (FFT) analysis. In addition, a concave correlation between the needle diameter and resultant fiber diameter was identified. This system can be easily scaled up for industrial production of highly-aligned nanofibers with tunable diameters that can potentially meet the requirements for various engineering and biomedical applications.

  3. High-yield expression of human vascular endothelial growth factor VEGF(165) in Escherichia coli and purification for therapeutic applications.

    Science.gov (United States)

    Pizarro, Shelly A; Gunson, Jane; Field, Matthew J; Dinges, Rachel; Khoo, Stefanie; Dalal, Milind; Lee, Michael; Kaleas, Kimberly A; Moiseff, Kathryn; Garnick, Susan; Reilly, Dorothea E; Laird, Michael W; Schmelzer, Charles H

    2010-08-01

    Vascular endothelial growth factor (VEGF(165)) is a potent mitogen that induces angiogenesis and vascular permeability in vivo and has demonstrated potential in therapeutic applications for accelerating wound healing. An industrial production method that provides high yield as well as high purity, quality, and potency is needed. The process described in this report involves a bacterial expression system capable of producing approximately 9g of rhVEGF per liter of broth and a downstream purification process consisting of protein refolding and three chromatography steps prior to formulation of the drug substance. A high cell density (HCD) fed-batch fermentation process was used to produce rhVEGF in periplasmic inclusion bodies. The inclusion bodies are harvested from the cell lysate and subjected to a single-step protein solubilization and refolding operation to extract the rhVEGF for purification. Overall recovery yields observed during development, including refolding and chromatography, were 30+/-6%. Host cell impurities are consistently cleared below target levels at both laboratory and large-scale demonstrating process robustness. The structure of the refolded and purified rhVEGF was confirmed by mass spectrometry, N-terminal sequencing, and tryptic peptide mapping while product variants were analyzed by multiple HPLC assays. Biological activity was verified by the proliferation of human umbilical vein derived endothelial cells. Copyright 2010 Elsevier Inc. All rights reserved.

  4. Development of crossbreeding high-yield-potential strains for commercial cultivation in the medicinal mushroom Wolfiporia cocos (Higher Basidiomycetes).

    Science.gov (United States)

    Xiang, Xiaozhao; Wang, Xiaoxia; Bian, Yinbing; Xu, Zhangyi

    2016-07-01

    Wolfiporia cocos is a well-known medicinal mushroom, and its dried sclerotia has been widely used as a traditional medicine in China, Japan, and other Asian countries for centuries. However, long-term asexual reproduction of the breeding system in W. cocos results in a current universal degeneration of cultivated strains. To develop a W. cocos breeding program that will benefit commercial cultivation, we previously developed an optimum method for indoor induction of W. cocos fruiting bodies and clarified the nature of preponderant binuclear sexual basidiospores. In this paper, we first show that the majority of W. cocos single-spore isolates cannot form sclerotium in field cultivation. We then investigated the possibility of breeding new strains by crossbreeding. Three types of mating reactions were observed in both intra-strain pairings and inter-strain pairings, and a total of fifty-five hybrids were selected by antagonistic testing and allele-specific polymerase chain reaction (PCR). Field cultivation of hybrids demonstrated that some hybrids can form sclerotium via two cultivated methods. Two new high-yield strains were identified. This report will stimulate new thinking on W. cocos and promote further extensive studies on crossbreeding in W. cocos, a new topic related to the development of more efficient protocols for the discrimination of hybrids in W. cocos.

  5. Microstructure and Mechanical Properties in Hot-Rolled Extra High-Yield-Strength Steel Plates for Offshore Structure and Shipbuilding

    Science.gov (United States)

    Liu, Dongsheng; Li, Qingliang; Emi, Toshihiko

    2011-05-01

    Key parameters for a thermomechanically controlled processing and accelerated cooling process (TMCP-AcC) were determined for integrated mass production to produce extra high-yield-strength microalloyed low carbon SiMnCrNiCu steel plates for offshore structure and bulk shipbuilding. Confocal scanning microscopy was used to make in-situ observations on the austenite grain growth during reheating. A Gleeble 3800 thermomechanical simulator was employed to investigate the flow stress behavior, static recrystallization (SRX) of austenite, and decomposition behavior of the TMCP conditioned austenite during continuous cooling. The Kocks-Mecking model was employed to describe the constitutive behavior, while the Johnson-Mehl-Avrami-Kolmogorov (JMAK) approach was used to predict the SRX kinetics. The effects of hot rolling schedule and AcC on microstructure and properties were investigated by test-scale rolling trials. The bridging between the laboratory observations and the process parameter determination to optimize the mass production was made by integrated industrial production trials on a set of a 5-m heavy plate mill equipped with an accelerated cooling system. Successful production of 60- and 50-mm-thick plates with yield strength in excess of 460 MPa and excellent toughness at low temperature (213 K (-60 °C)) in the parent metal and the simulated coarse-grained heat affected zone (CGHAZ) provides a useful integrated database for developing advanced high-strength steel plates via TMCP-AcC.

  6. Rapid Seedless Synthesis of Gold Nanoplates with Microscaled Edge Length in a High Yield and Their Application in SERS

    Institute of Scientific and Technical Information of China (English)

    Sheng Chen; Pengyu Xu; Yue Li; Junfei Xue; Song Han; Weihui Ou; Li Li; Weihai Ni

    2016-01-01

    We report a facile and reproducible approach toward rapid seedless synthesis of single crystalline gold nano-plates with edge length on the order of microns. The reaction is carried out by reducing gold ions with ascorbic acid in the presence of cetyltrimethylammonium bromide (CTAB). Reaction temperature and molar ratio of CTAB/Au are critical for the formation of gold nanoplates in a high yield, which are, respectively, optimized to be 85 °C and 6. The highest yield that can be achieved is 60%at the optimized condition. The synthesis to achieve the microscaled gold nanoplates can be finished in less than 1 h under proper reaction conditions. Therefore, the reported synthesis approach is a time-and cost-effective one. The gold nanoplates were further employed as the surface-enhanced Raman scattering substrates and investigated individually. Interestingly, only those adsorbed with gold nanoparticles exhibit pronounced Raman signals of probe molecules, where a maximum enhancement factor of 1.7 × 107 was obtained. The obtained Raman enhancement can be ascribed to the plasmon coupling between the gold nanoplate and the nanoparticle adsorbed onto it.

  7. A Study of Mutation Breeding of High-Yielding Tryptophanase Escherichia coli by Low-Energy N+ Ion Beam Implantation

    Science.gov (United States)

    Pang, Min; Yao, Jianming; Wang, Dongmei

    2009-12-01

    Low energy ion beam has been widely applied in microbe breeding, plant breeding, gene transfer and cell modification. In this study, the Escherichia coli (E.coli) strain producing tryptophanase was irradiated by a low energy nitrogen ion beam with an energy of 10 keV at a fluence of 13 × 1014 N+/cm2 when glycerin at a 15% concentration was used as a protector. The effect on the biomass of E. coli after N+ implantation was analyzed in detail by statistic methods. The screening methods used in this study were proven to be effective. After continuous mutagenicity, a high-yield tryptophanase strain was selected and both its biomass and enzymatic activity were higher than those of the parent strain. The results of scale-up production showed that the biomass could reach wet weight 8.2 g/L and 110 g L-tryptophan could be formed in the volume of the 1l enzymatic reaction system.

  8. Gram-scale, high-yield synthesis of a robust metal-organic framework for storing methane and other gases

    Energy Technology Data Exchange (ETDEWEB)

    Wilmer, CE; Farha, OK; Yildirim, T; Eryazici, I; Krungleviciute, V; Sarjeant, AA; Snurr, RQ; Hupp, JT

    2013-04-01

    We have synthesized and characterized a new metal-organic framework (MOF) material, NU-125, that, in the single-crystal limit, achieves a methane storage density at 58 bar (840 psi) and 298 K corresponding to 86% of that obtained with compressed natural gas tanks (CNG) used in vehicles today, when the latter are pressurized to 248 bar (3600 psi). More importantly, the deliverable capacity (58 bar to 5.8 bar) for NU-125 is 67% of the deliverable capacity of a CNG tank that starts at 248 bar. (For crystalline granules or powders, particle packing inefficiencies will yield densities and deliverable capacities lower than 86% and 67% of high-pressure CNG.) This material was synthesized in high yield on a gram-scale in a single-batch synthesis. Methane adsorption isotherms were measured over a wide pressure range (0.1-58 bar) and repeated over twelve cycles on the same sample, which showed no detectable degradation. Adsorption of CO2 and H-2 over a broad range of pressures and temperatures are also reported and agree with our computational findings.

  9. Changes in Some Physiological Characteristics After Full Heading Stage in Flag Leaves of Super High-Yielding Inbred Rice

    Institute of Scientific and Technical Information of China (English)

    HUANG Min; ZOU Yingbin

    2009-01-01

    In a field experiment, rice cultivar Shanyou 63 was used as a check cuitivar to investigate the changes in activity of peroxidase and contents of malondialdehyde and soluble protein after full heading stage in flag leaves of two super high-yielding inbred rice, including Shengtai 1 and Yuxiangyouzhan. The results showed that the peroxidase activities and soluble protein contents in the leaves of the three cultivars tended to increase gradually to peak values and thereafter descended during stage after full heading. Moreover, both the peroxidase activities and soluble protein contents of Shengtai 1 and Yuxiangyouzhan peaked at 8 days after full heading, which was compared with that of Shanyou 63 at 4 days later. Meanwhile, the malondialdehyde contents in the leaves of the three cultivars increased gradually after full heading stage. In addition, activities of peroxidase and contents of malondialdehyde and soluble protein in different cultivars were various at the same time. In general, for Shengtai 1 and Yuxiangyouzhan, the peroxidase activities and soluble protein contents were higher than those of Shanyou 63, whereas the malondialdehyde contents were lower compared with that of Shanyou 63. And these features could make the senescence of leaf become later and slower and photosynthetic product was more in Shengtai 1 and Yuxiangyouzhan than that in Shanyou 63.

  10. Practice and Thought on Developing Hybrid Rice for Super High Yield by Exploiting Inter-subspecific Heterosis

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Since the breakthrough of grain yield owing to the development of dwarf rice and three-line system hybrid rice, rice breeding for high yield hardly had showed significant progress in the next successive two decades. It was considered that utilizing heterosis between subspecific varieties (Oryza sativa L.) would be an effective approach to increase yield further. During 1987-1993,an indica-japonica hybrid Yayou 2 yielded as high as 10.5 t/ha; however, it failed to be commercialized because of seed purity problem due to non-uniform emasculation by chemical agent in seed production, and sensitivity of seed setting in F1 plants to environmental conditions. In the past decade, two inter-subspeific hybrids, Liangyoupeijiu (Peiai 64S/9311, javanica/indica) and Liangyou E32 (Peiai 64S/E32, javanica/japonica); both of them exhibited grain yield higher than 10.5 t/ha, and were widely judged as the pioneers of super hybrid rice. Liangyoupeijiu has been successfully popularized over 4 million hectare in wide climatic areas, while Liangyou E32 made a yield record and offered a model of plant ideotype for super hybrid rice. It was considered that in combination with plant ideotype, active physiological functions, and wide-range adaptability to ecological conditions, exploitation of indica-japonica heterosis would be the key approach for super hybrid rice breeding.

  11. High yield stress associated with capillary attraction between alumina surfaces in the presence of low molecular weight dicarboxylic acids.

    Science.gov (United States)

    Teh, E-Jen; Leong, Yee-Kwong; Liu, Yinong; Craig, Vincent S J; Walsh, Rick B; Howard, Shaun C

    2010-03-02

    Adsorbed low molecular weight charged molecules are known to give rise to a range of surface forces that affect the rheological behavior of oxide dispersions. The behavior of dicarboxylic acid bolaform compounds in alumina slurry was investigated to determine the influence of the molecular structure on the nanoscale interactions between alumina surfaces and on the macroscopic properties of the slurry. The surface forces in dispersions and between a single particle and a flat surface were characterized by yield stress and atomic force microscopy (AFM) respectively. Absorbed muconic acid increased the yield stress of the alumina system, which indicates an additional attractive interaction between the particles. Adsorbed trans,trans (TT) muconic acid resulted in a much higher yield stress than cis,cis (CC) muconic acid. Force-distance data obtained via AFM displayed features indicating the presence of a capillary force attraction at low pH between the alumina surfaces when TT and CC muconic acids were adsorbed at high surface coverage. This force appeared to explain the high yield stress at low pH (pH 3.6), but the absence of a net attractive force at higher pH (pH 5) did not correlate with the yield stress results. At low pH, the muconic acids become less soluble in the confined space between the interacting surfaces resulting in the formation of an "oily" muconic acid phase located between the interacting surfaces. The nanosized "oil" phase is the source of the capillary force.

  12. Zhongdanyaozhi No. 1 and Zhongdanyaozhi No. 2 Are Hybrid Cultivars of Salvia miltiorrhiza with High Yield and Active Compounds Content

    Science.gov (United States)

    Sui, Chun; Jin, Yue; Wei, Jianhe

    2016-01-01

    Salvia miltiorrhiza Bunge is an important medicinal plant used for the treatment of cardiovascular disease. Intraspecific hybridization between a male sterile line and inbred lines was followed by 39 F1 crossings. Cultivars “Zhongdanyaozhi No. 1” (ZD1) and “Zhongdanyaozhi No. 2” (ZD2) were obtained. In 2012 and 2013 tests in Beijing, the two cultivars were compared with three widely accepted types, SDCK, SXCK and HNCK from Shandong, Shanxi and Henan provinces. The yield of ZD1 and ZD2 exceeded the three CKs by more than 48.2% and 39.2%, respectively; the composition of the two hybrid cultivars was similar to the control, although the content of some compounds varied to some extent. The content of salvianolic acid B and tanshinone II A of both ZD1 and ZD2 could measure up the requirement of Chinese Pharmacopoeia. The former showed no obvious advantage than the three CKs, while the later’s tanshinone II A was 29.6% higher than the three CKs. Taken together, ZD1 is a high yielding and thick-root-type cultivar which is suitable for decoction pieces; while ZD2 is suitable for component especially lipophilic component extraction. ZD1 and ZD2 reported here are the first cultivars obtained by the hybridization of S. miltiorrhiza. PMID:27658029

  13. Toward Self-Assembled Plasmonic Devices: High-Yield Arrangement of Gold Nanoparticles on DNA Origami Templates.

    Science.gov (United States)

    Gür, Fatih N; Schwarz, Friedrich W; Ye, Jingjing; Diez, Stefan; Schmidt, Thorsten L

    2016-05-24

    Plasmonic structures allow the manipulation of light with materials that are smaller than the optical wavelength. Such structures can consist of plasmonically active metal nanoparticles and can be fabricated through scalable bottom-up self-assembly on DNA origami templates. To produce functional devices, the precise and high-yield arrangement of each of the nanoparticles on a structure is of vital importance as the absence of a single particle can destroy the functionality of the entire device. Nevertheless, the parameters influencing the yield of the multistep assembly process are still poorly understood. To overcome this deficiency, we employed a test system consisting of a tubular six-helix bundle DNA origami with binding sites for eight oligonucleotide-functionalized gold nanoparticles. We systematically studied the assembly yield as a function of a wide range of parameters such as ionic strength, stoichiometric ratio, oligonucleotide linker chemistry, and assembly kinetics by an automated high-throughput analysis of electron micrographs of the formed heterocomplexes. Our optimized protocols enable particle placement yields up to 98.7% and promise the reliable production of sophisticated DNA-based multiparticle plasmonic devices for applications in photonics, optoelectronics, and nanomedicine.

  14. Biocontrol potential of Halotolerant bacterial chitinase from high yielding novel Bacillus Pumilus MCB-7 autochthonous to mangrove ecosystem.

    Science.gov (United States)

    Rishad, K S; Rebello, Sharrel; Shabanamol, P S; Jisha, M S

    2017-04-01

    The multifaceted role of chitinase in medicine, agriculture, environmental remediation and various other industries greatly demands the isolation of high yielding chitinase producing microorganisms with improved properties. The current study aimed to investigate the isolation, characterization and biocontrol prospective of chitinase producing bacterial strains autochthonous to the extreme conditions of mangrove ecosystems. Among the 51 bacterial isolates screened, Bacillus pumilus MCB-7 with highest chitinase production potential was identified and confirmed by 16S rDNA typing. Chitinase enzyme of MCB-7 was purified; the chitin degradation was evaluated by SEM and LC-MS. Unlike previously reported B.pumilus isolates, MCB-7 exhibited highest chitinase activity of 3.36U/mL, active even at high salt concentrations and temperature up to 60°C. The crude as well as purified enzyme showed significant antimycotic activity against agricultural pathogens such as Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, Ceratorhiza hydrophila and Fusarium oxysporum. The enzyme also exhibited biopesticidal role against larvae of Scirpophaga incertulas (Walker). [Lep.: Pyralidae], a serious agricultural pest of rice. The high chitinolytic and antimycotic potential of MCB-7 increases the prospects of the isolate as an excellent biocontrol agent. To the best of our knowledge, this is the first report of high chitinase yielding Bacillus pumilus strain from mangrove ecosystem with a biocontrol role against phytopathogenic fungi and insect larval pests. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. High yields of fatty acid and neutral lipid production from cassava bagasse hydrolysate (CBH) by heterotrophic Chlorella protothecoides.

    Science.gov (United States)

    Chen, Junhui; Liu, Xiaoguang; Wei, Dong; Chen, Gu

    2015-09-01

    The fermentation process for high yields of fatty acid and neutral lipid production from cassava bagasse hydrolysate (CBH) was developed by heterotrophic Chlorella protothecoides. An efficient single-step enzymatic hydrolysis of cassava bagasse (CB) by cellulase was firstly developed to produce >30 g/L of reducing sugars. The concentrated CBH was subsequently applied in a batch culture, producing 7.9 g/L of dry biomass with yield of 0.44 g/g reducing sugar and 34.3 wt% of fatty acids and 48.6 wt% of neutral lipids. Furthermore, fed-batch fermentation using CBH achieved higher yields of fatty acids (41.0 wt% and a titer of 5.83 g/L) and neutral lipids (58.4 wt% and yield of 0.22 g/g reducing sugar). Additionally, the fatty acid profile analysis showed that the intercellular lipid was suitable to prepare high-quality biodiesel. This study demonstrated the feasibility of using CBH as low-cost feedstock to produce crude algal oil for sustainable biodiesel production.

  16. Facile Growth of High-Yield Gold Nanobipyramids Induced by Chloroplatinic Acid for High Refractive Index Sensing Properties

    Science.gov (United States)

    Fang, Caihong; Zhao, Guili; Xiao, Yanling; Zhao, Jun; Zhang, Zijun; Geng, Baoyou

    2016-11-01

    Au nanobipyramids (NBPs) have attracted great attention because of their unique localized surface plasmon resonance properties. However, the current growth methods always have low yield or suffer tedious process. Developing new ways to direct synthesis of high-yield Au NBPs using common agents is therefore desirable. Here, we employed chloroplatinic acid as the key shape-directing agent for the first time to grow Au NBPs using a modified seed-mediated method at room temperature. H2PtCl6 was added both during the seed preparation and in growth solution. Metallic Pt, reduced from chloroplatinic acid, will deposit on the surface of the seed nanoparticles and the Au nanocrystals and thus plays a critical role for the formation of Au NBPs. Additionally, the reductant, precursor, and surfactant are all cheap and commonly used. Furthermore, the Au NBPs offer narrow size distribution, two sharp tips, and a shared basis. Au NBPs therefore show much higher refractive index sensitivities than that of the Au nanorods. The refractive index sensitivities and lager figure of merit values of Au NBPs exhibit an increase of 63% and 321% respectively compared to the corresponding values of Au nanorod sample.

  17. Screening of High Yield Strain for Tylosin%泰乐菌素高产菌株的筛选

    Institute of Scientific and Technical Information of China (English)

    张明明; 万丹; 徐玉崇; 刘迎宾; 张小红

    2015-01-01

    以弗氏链霉菌( Streptomyces fradiae ) TP-116菌株作为出发菌株,采用紫外线、氯化锂和微波三重复合诱变,通过泰乐菌素抗性定向筛选,获得一株高产菌株YBT-06,并对其进行了遗传稳定性试验,结果表明突变株YBT-06生产代谢旺盛,遗传稳定性好,发酵效价比出发菌株提高了25%,达到11066μg/mL。%Taking TP-116 strain of Streptomyces fradiae as a starting strain , using UV, lithium chloride and microwave triple compound mutagenesis , a high yield strainYBT-06 was got through the resistance of tylosin directional selection .The results on the genetic stability test showed that the mutant strain YBT -06 production metabolism exuberant , genetic stability was good , fermentation effect price had improved 25%than starting strains , reached 11066 μg/mL.

  18. Rapid high-yield expression of full-size IgG antibodies in plants coinfected with noncompeting viral vectors.

    Science.gov (United States)

    Giritch, Anatoli; Marillonnet, Sylvestre; Engler, Carola; van Eldik, Gerben; Botterman, Johan; Klimyuk, Victor; Gleba, Yuri

    2006-10-03

    Plant viral vectors allow expression of heterologous proteins at high yields, but so far, they have been unable to express heterooligomeric proteins efficiently. We describe here a rapid and indefinitely scalable process for high-level expression of functional full-size mAbs of the IgG class in plants. The process relies on synchronous coinfection and coreplication of two viral vectors, each expressing a separate antibody chain. The two vectors are derived from two different plant viruses that were found to be noncompeting. Unlike vectors derived from the same virus, noncompeting vectors effectively coexpress the heavy and light chains in the same cell throughout the plant body, resulting in yields of up to 0.5 g of assembled mAbs per kg of fresh-leaf biomass. This technology allows production of gram quantities of mAbs for research purposes in just several days, and the same protocol can be used on an industrial scale in situations requiring rapid response, such as pandemic or terrorism events.

  19. High-yield secretion of recombinant proteins expressed in tobacco cell culture with a designer glycopeptide tag: Process development.

    Science.gov (United States)

    Zhang, Ningning; Gonzalez, Maria; Savary, Brett; Xu, Jianfeng

    2016-03-01

    Low-yield protein production remains the most significant economic hurdle with plant cell culture technology. Fusions of recombinant proteins with hydroxyproline-O-glycosylated designer glycopeptide tags have consistently boosted secreted protein yields. This prompted us to study the process development of this technology aiming to achieve productivity levels necessary for commercial viability. We used a tobacco BY-2 cell culture expressing EGFP as fusion with a glycopeptide tag comprised of 32 repeat of "Ser-Pro" dipeptide, or (SP)32 , to study cell growth and protein secretion, culture scale-up, and establishment of perfusion cultures for continuous production. The BY-2 cells accumulated low levels of cell biomass (~7.5 g DW/L) in Schenk & Hildebrandt medium, but secreted high yields of (SP)32 -tagged EGFP (125 mg/L). Protein productivity of the cell culture has been stable for 6.0 years. The BY-2 cells cultured in a 5-L bioreactor similarly produced high secreted protein yield at 131 mg/L. Successful operation of a cell perfusion culture for 30 days was achieved under the perfusion rate of 0.25 and 0.5 day(-1) , generating a protein volumetric productivity of 17.6 and 28.9 mg/day/L, respectively. This research demonstrates the great potential of the designer glycopeptide technology for use in commercial production of valuable proteins with plant cell cultures. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Neutron scattering. Lectures

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2010-07-01

    The following topics are dealt with: Neutron sources, symmetry of crystals, diffraction, nanostructures investigated by small-angle neutron scattering, the structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic scattering, strongly correlated electrons, dynamics of macromolecules, applications of neutron scattering. (HSI)

  1. Neutron Capture Nucleosynthesis

    CERN Document Server

    Kiss, Miklos

    2016-01-01

    Heavy elements (beyond iron) are formed in neutron capture nucleosynthesis processes. We have proposed a simple unified model to investigate the neutron capture nucleosynthesis in arbitrary neutron density environment. We have also investigated what neutron density is required to reproduce the measured abundance of nuclei assuming equilibrium processes. We found both of these that the medium neutron density has a particularly important role at neutron capture nucleosynthesis. About these results most of the nuclei can formed at medium neutron capture density environment e.g. in some kind of AGB stars. Besides these observations our model is capable to use educational purpose.

  2. Glucose concentration and blood acid-basis status in high-yielding dairy cows during heat stress

    Directory of Open Access Journals (Sweden)

    Vujanac Ivan

    2011-01-01

    Full Text Available The objective of this work was to examine the effect of heat stress on glucose and pH values in blood of high-yielding dairy cows in the early stage of lactation, as well as to determine whether the changes in these parameters are interdependent under such conditions. An experiment was performed on high-yielding dairy cows during the summer and the spring periods. Forty cows were selected, twenty each for the two periods under investigation. In the course of the experiment, the temperature humidity index (THI was determined for the entire period of investigations, and then also the average daily THI, nightmorning THI (average value of hourly THI measured from 22h on the previous day until 10h of the current day, as well as the day-night THI (average value of hourly THI measured during the period from 10h to 22h of the current day. The pH and glucose concentration were determined in blood samples taken in the morning and afternoon of days 30, 60, and 90 of lactation during the spring and summer periods of the investigations. Based on the results for the THI, it was established that the animals were not exposed to the effect of extreme heat stress during the spring period of investigations, while they were periodically exposed to moderate but also extreme heat stress during the summer, in particular in the afternoon hours. It can be concluded from the results obtained for the blood pH that the cows were in respiratory alkalosis during the summer in the morning and afternoon hours on day 30, in the afternoon hours of days 60 and 90 of lactation, as well as in the afternoon on day 90 of lactation during the spring period of investigations. During the summer period, there were no statistically significant differences between the pH value determined in the morning and afternoon hours on day 30 of lactation, while the pH value was significantly higher in the afternoon hours than in the morning hours on days 60 and 90 of lactation. There were no

  3. Optimized Design of Spacing in Pulsed Neutron Gamma Density Logging While Drilling

    Directory of Open Access Journals (Sweden)

    ZHANG Feng;HAN Zhong-yue;WU He;HAN Fei

    2016-10-01

    Full Text Available Radioactive source, used in traditional density logging, has great impact on the environment, while the pulsed neutron source applied in the logging tool is more safety and greener. In our country, the pulsed neutron-gamma density logging technology is still in the stage of development. Optimizing the parameters of neutron-gamma density instrument is essential to improve the measuring accuracy. This paper mainly studied the effects of spacing to typical neutron-gamma density logging tool which included one D-T neutron generator and two gamma scintillation detectors. The optimization of spacing were based on measuring sensitivity and counting statistic. The short spacing from 25 to 35 cm and long spacing from 60 to 65 cm were selected as the optimal position for near and far detector respectively. The result can provide theoretical support for design and manufacture of the instrument.

  4. Calibration of LiBaF sub 3 Ce scintillator for fission spectrum neutrons

    CERN Document Server

    Reeder, P L

    2002-01-01

    The scintillator LiBaF sub 3 doped with small amounts of Ce sup + sup 3 has the ability to distinguish heavy charged particles (p, d, t, or alpha) from beta and/or gamma radiation based on the presence or absence of nanosecond components in the scintillation light output. Since the neutron capture reaction on sup 6 Li produces recoil alphas and tritons, this scintillator also discriminates between neutron induced events and beta or gamma interactions. An experimental technique using a time-tagged sup 2 sup 5 sup 2 Cf source has been used to measure the efficiency of this scintillator for neutron capture, the calibration of neutron capture pulse height, and the pulse height resolution--all as a function of incident neutron energy.

  5. Nuclear reactor neutron shielding

    Energy Technology Data Exchange (ETDEWEB)

    Speaker, Daniel P; Neeley, Gary W; Inman, James B

    2017-09-12

    A nuclear reactor includes a reactor pressure vessel and a nuclear reactor core comprising fissile material disposed in a lower portion of the reactor pressure vessel. The lower portion of the reactor pressure vessel is disposed in a reactor cavity. An annular neutron stop is located at an elevation above the uppermost elevation of the nuclear reactor core. The annular neutron stop comprises neutron absorbing material filling an annular gap between the reactor pressure vessel and the wall of the reactor cavity. The annular neutron stop may comprise an outer neutron stop ring attached to the wall of the reactor cavity, and an inner neutron stop ring attached to the reactor pressure vessel. An excore instrument guide tube penetrates through the annular neutron stop, and a neutron plug comprising neutron absorbing material is disposed in the tube at the penetration through the neutron stop.

  6. Laue crystal structure of Shewanella oneidensis cytochrome c nitrite reductase from a high-yield expression system

    Energy Technology Data Exchange (ETDEWEB)

    Youngblut, Matthew; Judd, Evan T.; Srajer, Vukica; Sayyed, Bilal; Goelzer, Tyler; Elliott, Sean J.; Schmidt, Marius; Pacheco, A. Andrew (UW); (UC); (BU)

    2012-09-11

    The high-yield expression and purification of Shewanella oneidensis cytochrome c nitrite reductase (ccNiR) and its characterization by a variety of methods, notably Laue crystallography, are reported. A key component of the expression system is an artificial ccNiR gene in which the N-terminal signal peptide from the highly expressed S. oneidensis protein 'small tetraheme c' replaces the wild-type signal peptide. This gene, inserted into the plasmid pHSG298 and expressed in S. oneidensis TSP-1 strain, generated approximately 20 mg crude ccNiR per liter of culture, compared with 0.5-1 mg/L for untransformed cells. Purified ccNiR has nitrite and hydroxylamine reductase activities comparable to those previously reported for Escherichia coli ccNiR, and is stable for over 2 weeks in pH 7 solution at 4 C. UV/vis spectropotentiometric titrations and protein film voltammetry identified five independent one-electron reduction processes. Global analysis of the spectropotentiometric data also allowed determination of the extinction coefficient spectra for the five reduced ccNiR species. The characteristics of the individual extinction coefficient spectra suggest that, within each reduced species, the electrons are distributed among the various hemes, rather than being localized on specific heme centers. The purified ccNiR yielded good-quality crystals, with which the 2.59-{angstrom}-resolution structure was solved at room temperature using the Laue diffraction method. The structure is similar to that of E. coli ccNiR, except in the region where the enzyme interacts with its physiological electron donor (CymA in the case of S. oneidensis ccNiR, NrfB in the case of the E. coli protein).

  7. [A hydroponic cultivation system for rapid high-yield transient protein expression in Nicotiana plants under laboratory conditions].

    Science.gov (United States)

    Mo, Qianzhen; Mai, Rongjia; Yang, Zhixiao; Chen, Minfang; Yang, Tiezhao; Lai, Huafang; Yang, Peiliang; Chen, Qiang; Zhou, Xiaohong

    2012-06-01

    To develop a hydroponic Nicotiana cultivation system for rapid and high-yield transient expression of recombinant proteins under laboratory conditions. To establish the hydroponic cultivation system, several parameters were examined to define the optimal conditions for the expression of recombinant proteins in plants. We used the green fluorescent protein (GFP) and the geminiviral plant transient expression vector as the model protein/expression vector. We examined the impact of Nicotiana species, the density and time of Agrobacterium infiltration, and the post-infiltration growth period on the accumulation of GFP. The expression levels of GFP in Nicotiana leaves were then examined by Western blotting and ELISA. Our data indicated that a hydroponic Nicotiana cultivation system with a light intensity of 9000 LX/layer, a light cycle of 16 h day/8 h night, a temperature regime of 28 degrees celsius; day/21 degrees celsius; night, and a relative humidity of 80% could support the optimal plant growth and protein expression. After agroinfiltration with pBYGFPDsRed.R/LBA4404, high levels of GFP expression were observed in both N. benthamiana and N. tobaccum (cv. Yuyan No.5) plants cultured with this hydroponic cultivation system. An optimal GFP expression was achieved in both Nicotiana species leaves 4 days after infiltration by Agrobacterium with an OD(600) of 0.8. At a given time point, the average biomass of N. tobaccum (cv. Yuyan No.5) was significantly higher than that of N. benthamiana. The leaves from 6-week-old N. benthamiana plants and 5-week-old N. tobaccum (cv. Yuyan No.5) plants could be the optimal material for agroinfiltration. We have established a hydroponic cultivation system that allows robust growth of N. benthamiana and N. tobaccum (cv. Yuyan No.5) plants and the optimal GFP expression in the artificial climate box.

  8. Global warming potential and greenhouse gas intensity in rice agriculture driven by high yields and nitrogen use efficiency

    Science.gov (United States)

    Zhang, Xiaoxu; Xu, Xin; Liu, Yinglie; Wang, Jinyang; Xiong, Zhengqin

    2016-05-01

    Our understanding of how global warming potential (GWP) and greenhouse gas intensity (GHGI) is affected by management practices aimed at food security with respect to rice agriculture remains limited. In the present study, a field experiment was conducted in China to evaluate the effects of integrated soil-crop system management (ISSM) on GWP and GHGI after accounting for carbon dioxide (CO2) equivalent emissions from all sources, including methane (CH4) and nitrous oxide (N2O) emissions, agrochemical inputs and farm operations and sinks (i.e., soil organic carbon sequestration). The ISSM mainly consisted of different nitrogen (N) fertilization rates and split, manure, Zn and Na2SiO3 fertilization and planting density for the improvement of rice yield and agronomic nitrogen use efficiency (NUE). Four ISSM scenarios consisting of different chemical N rates relative to the local farmers' practice (FP) rate were carried out, namely, ISSM-N1 (25 % reduction), ISSM-N2 (10 % reduction), ISSM-N3 (FP rate) and ISSM-N4 (25 % increase). The results showed that compared with the FP, the four ISSM scenarios significantly increased the rice yields by 10, 16, 28 and 41 % and the agronomic NUE by 75, 67, 35 and 40 %, respectively. In addition, compared with the FP, the ISSM-N1 and ISSM-N2 scenarios significantly reduced the GHGI by 14 and 18 %, respectively, despite similar GWPs. The ISSM-N3 and ISSM-N4 scenarios remarkably increased the GWP and GHGI by an average of 69 and 39 %, respectively. In conclusion, the ISSM strategies are promising for both food security and environmental protection, and the ISSM scenario of ISSM-N2 is the optimal strategy to realize high yields and high NUE together with low environmental impacts for this agricultural rice field.

  9. High-Yield Superovulation in Adult Mice by Anti-Inhibin Serum Treatment Combined with Estrous Cycle Synchronization.

    Science.gov (United States)

    Hasegawa, Ayumi; Mochida, Keiji; Inoue, Hiroki; Noda, Yoshihiro; Endo, Tamao; Watanabe, Gen; Ogura, Atsuo

    2016-01-01

    Producing many mature oocytes is of great importance for assisted reproductive technologies. In mice, superovulation by consecutive injections of equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG) has been the gold standard for oocyte collection. However, the yield of mature oocytes by this regimen can fluctuate according to the stage of the estrous cycle, strain, and age. Therefore, our objective was to develop a high-yield superovulation protocol to collect higher numbers of oocytes from adult female mice of different strains and ages. First, we aimed to synchronize the estrous cycle using C57BL/6 (B6) female mice. Most (93%) were synchronized to metestrus after two daily injections of progesterone. Second, we found that with the injection of anti-inhibin serum (AIS) instead of eCG, the mean number of ovulated oocytes almost doubled (21 vs. 41 per mouse). Third, by combining estrous cycle synchronization with two AIS injections, we obtained 62 oocytes per mouse, about three times that with the eCG-hCG protocol. Importantly, this approach increased the proportion of mice that ovulated >25 oocytes from about 40% (eCG-hCG) to 90%. The same protocol was also effective in other inbred (BALB/cA), outbred (ICR), and hybrid (B6D2F1) strains. In addition, B6 female mice aged over 1 yr ovulated 1.8-fold more oocytes by this protocol. Thus, estrous cycle synchronization followed by AIS-hCG yielded a broadly applicable, highly efficient superovulation. This protocol should promote the effective use of invaluable female mouse strains and decrease the numbers of animals euthanized. © 2016 by the Society for the Study of Reproduction, Inc.

  10. Multistage Solvent Extraction for High Yield Oil and Phorbol Esters Removal from Thai Toxic Jatropha curcas Meal

    Directory of Open Access Journals (Sweden)

    Rayakorn NOKKAEW

    2015-04-01

    Full Text Available In this study, we investigate the possibility for the production of high yield oil and phorbol esters removed from Thai toxic Jatropha curcas meal. Optimum oil recovery by hexane extraction to obtain high oil yield was accomplished in 3 stages of batch extraction, following which the de-oiled meal was further determined for the optimum conditions for removal of phorbol esters (PEs by aqueous ethanol extraction from the first to the third stage of batch extraction with the aim of yielding detoxified de-oiled meal product for use as a raw material in animal feed. The optimum conditions for oil extraction was 3-stage extraction with each stage operated at 1:3 (w/v of toxic meal to hexane at 40 °C for 30 min. This condition gave 100 % de-oiling efficiency compared with the Soxhlet extraction method. The optimum condition for PEs removal from the de-oiled meal involved 2-stage extraction with each stage operated at 1:3 (w/v of de-oiled meal to aqueous ethanol at 50 °C for 30 min. Liquid chromatography-tandem mass spectrometry (LC-MS/MS in the multiple reaction monitoring mode, was used to confirm the PEs residue in the detoxified de-oiled meal. The confirmation showed that the 2 stages of PEs extraction could remove 100 % of the PEs from the de-oiled meal. The results from our study can provide the basis for the efficient commercial production of both J. curcas oil and detoxified de-oiled meal.

  11. Metabolic engineering for the high-yield production of isoprenoid-based C₅ alcohols in E. coli.

    Science.gov (United States)

    George, Kevin W; Thompson, Mitchell G; Kang, Aram; Baidoo, Edward; Wang, George; Chan, Leanne Jade G; Adams, Paul D; Petzold, Christopher J; Keasling, Jay D; Lee, Taek Soon

    2015-06-08

    Branched five carbon (C5) alcohols are attractive targets for microbial production due to their desirable fuel properties and importance as platform chemicals. In this study, we engineered a heterologous isoprenoid pathway in E. coli for the high-yield production of 3-methyl-3-buten-1-ol, 3-methyl-2-buten-1-ol, and 3-methyl-1-butanol, three C5 alcohols that serve as potential biofuels. We first constructed a pathway for 3-methyl-3-buten-1-ol, where metabolite profiling identified NudB, a promiscuous phosphatase, as a likely pathway bottleneck. We achieved a 60% increase in the yield of 3-methyl-3-buten-1-ol by engineering the Shine-Dalgarno sequence of nudB, which increased protein levels by 9-fold and reduced isopentenyl diphosphate (IPP) accumulation by 4-fold. To further optimize the pathway, we adjusted mevalonate kinase (MK) expression and investigated MK enzymes from alternative microbes such as Methanosarcina mazei. Next, we expressed a fusion protein of IPP isomerase and the phosphatase (Idi1~NudB) along with a reductase (NemA) to diversify production to 3-methyl-2-buten-1-ol and 3-methyl-1-butanol. Finally, we used an oleyl alcohol overlay to improve alcohol recovery, achieving final titers of 2.23 g/L of 3-methyl-3-buten-1-ol (~70% of pathway-dependent theoretical yield), 150 mg/L of 3-methyl-2-buten-1-ol, and 300 mg/L of 3-methyl-1-butanol.

  12. Weapons Neutron Research Facility (WNR)

    Data.gov (United States)

    Federal Laboratory Consortium — The Weapons Neutron Research Facility (WNR) provides neutron and proton beams for basic, applied, and defense-related research. Neutron beams with energies ranging...

  13. Neutron irradiation effects on superconducting wires and insulating materials

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Arata [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan)], E-mail: nishi-a@nifs.ac.jp; Takeuchi, Takao [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Nishijima, Shigehiro [Graduate School of Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Nishijima, Gen; Shikama, Tatsuo [Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan); Ochiai, Kentaro [Japan Atomic Energy Agency, 2-4 Shirakata Shirane, Tokai, Naka, Ibaraki 319-1195 (Japan); Koizumi, Norikiyo [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

    2009-06-15

    On the progress of the Deuterium-Deuterium (D-D) or Deuterium-Tritium (D-T) burning plasma devices, the importance of neutron irradiation on superconducting magnet materials increases and the data base is desired to design the next generation devices. To carry out the investigations on the effect of neutron irradiation, neutron irradiation fields are required together with post-irradiation test facilities. In these several years, a collaboration network of neutron irradiation effect on superconducting magnet materials has been constructed. 14 MeV neutron irradiation was carried out at Fusion Neutronics Sources (FNS) in Japan Atomic Energy Agency (JAEA) and fission neutron irradiation was performed at JRR-3 in JAEA. After the irradiation, the Nb{sub 3}Sn, NbTi and Nb{sub 3}Al samples were sent to High Field Laboratory for Superconducting Materials (HFLSM) in Tohoku University and the superconducting properties were evaluated with 28 T hybrid magnet. Also, the organic insulation materials are considered to be weaker than superconducting materials against neutron irradiation and cyanate ester resin composite was fabricated and tested at the fission reactor. One clear result on Nb{sub 3}Sn was the property change of Nb{sub 3}Sn by 14 MeV neutron irradiation over 13 T. The critical current was increased by 1.4 times around 13 T but the increment of the critical current became almost zero at higher magnetic fields and the critical magnetic field of the irradiated sample showed almost the same as non-irradiated one.

  14. China’s High-yield Pulp Sector and Its Carbon Dioxide Emission: Considering the Saved Standing Wood as an Increase of Carbon Storage

    Directory of Open Access Journals (Sweden)

    Yanhong Gao

    2014-11-01

    Full Text Available The production of high-yield pulp in China has increased significantly in recent years. The well-known advantages of this type of pulp include low production cost, high opacity, and good paper formation. In the context of state-of-the-art technologies, China’s high-yield pulping, which is dominated by the PRC-APMP (preconditioning refiner chemical treatment-alkaline peroxide mechanical pulping process, has a much higher energy input but a significantly lower wood consumption in comparison with the kraft pulping process. If the saved wood in the forest or plantation is considered as an increment of carbon storage, then the carbon dioxide emission from the production of high-yield pulp can be regarded as much lower than that of kraft pulp.

  15. Preparation of carbon-encapsulated iron nanoparticles in high yield by DC arc discharge and their characterization

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China); Cui, Lan; Lin, Kui [Center of Analysis, Tianjin University, Tianjin 300072 (China); Jin, Feng-min; Wang, Bin [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Shi, Shu-xiu [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China); Yang, De-an [School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Wang, Hui [Center of Analysis, Tianjin University, Tianjin 300072 (China); He, Fei [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Chen, Xiao-ping [Center of Analysis, Tianjin University, Tianjin 300072 (China); Cui, Shen, E-mail: cuishen@tju.edu.cn [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China)

    2013-03-15

    Highlights: ► CEINPs with core–shell structure and high Fe content were prepared in high yield by DC arc discharge. ► The anode II with a mass ratio of total iron to carbon 8:1 was used in DC arc discharge. ► The possible process of formation of CEINPs is briefly discussed. ► The uniformity of composition of anode is very important for the formation of CEINPs. ► The MEF and MMF of iron element may also play an important role in the formation of CEINPs. -- Abstract: Carbon-encapsulated iron nanoparticles (CEINPs) were prepared by DC arc discharge under nitrogen atmosphere of high temperature. The products were characterized by transmission electron microscope (TEM), high-resolution transmission electron microscope (HRTEM), X-ray diffractometer (XRD), energy dispersive X-ray (EDX) spectroscope, and X-ray photoelectron spectroscope (XPS), and their magnetic properties were measured by physical property measurement system (PPMS). The product B{sub I}, obtained from the anode I, contains the nanoparticles of iron and iron carbide, and carbon coating with imperfect and disordered layer structure. The product B{sub II}, obtained from the anode II, mainly consists of CEINPs, whose cores mainly consist of iron and iron carbide and shells contain about 3–7 graphitic layers. The iron contents in the products B{sub I} and B{sub II} are 44.8 and 82.6 wt.%, respectively. The products B{sub I} and B{sub II} have similar phase composition which includes carbon, iron, iron carbide, ferrous and ferric oxide, iron nitride, and carbon nitride. The saturation magnetization (Ms) of the products B{sub I} and B{sub II} are 29.35 and 88.66 emu/g and their coercivity (Hc) are 220 and 240 Oe, respectively. The total yields of all the products formed in the arc discharge chamber from anodes I and II, except for the cylinder-shaped deposits formed on the top of the cathode, are 25.8 and 22.3 wt.%, respectively. The possible process of formation of CEINPs is briefly discussed on

  16. 油菜高产栽培理论及综合配套栽培技术%High Yield Cultivation Technology and Application Effect of Rape

    Institute of Scientific and Technical Information of China (English)

    李双印

    2012-01-01

    基于油菜高产栽培理论.总结了油菜高产综合配套栽培技术,分析了其在生产应用上的效果,以期为油菜栽培提供理论参考。%Based on the high yield theory high yield cultivation comprehensive reform technique and application effect in production of rape were summarized, in order to provide theoretical reference for rape cultivation.

  17. Superheated drop neutron spectrometer

    CERN Document Server

    Das, M; Roy, B; Roy, S C; Das, Mala

    2000-01-01

    Superheated drops are known to detect neutrons through the nucleation caused by the recoil nuclei produced by the interactions of neutrons with the atoms constituting the superheated liquid molecule. A novel method of finding the neutron energy from the temperature dependence response of SDD has been developed. From the equivalence between the dependence of threshold energy for nucleation on temperature of SDD and the dependence of dE/dx of the recoil ions with the energy of the neutron, a new method of finding the neutron energy spectrum of a polychromatic as well as monochromatic neutron source has been developed.

  18. Neutron streak camera

    Science.gov (United States)

    Wang, Ching L.

    1983-09-13

    Apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon.

  19. Shielding evaluation of neutron generator hall by Monte Carlo simulations

    Energy Technology Data Exchange (ETDEWEB)

    Pujala, U.; Selvakumaran, T.S.; Baskaran, R.; Venkatraman, B. [Radiological Safety Division, Indira Gandhi Center for Atomic Research, Kalpakkam (India); Thilagam, L.; Mohapatra, D.K., E-mail: swathythila2@yahoo.com [Safety Research Institute, Atomic Energy Regulatory Board, Kalpakkam (India)

    2017-04-01

    A shielded hall was constructed for accommodating a D-D, D-T or D-Be based pulsed neutron generator (NG) with 4π yield of 10{sup 9} n/s. The neutron shield design of the facility was optimized using NCRP-51 methodology such that the total dose rates outside the hall areas are well below the regulatory limit for full occupancy criterion (1 μSv/h). However, the total dose rates at roof top, cooling room trench exit and labyrinth exit were found to be above this limit for the optimized design. Hence, additional neutron shielding arrangements were proposed for cooling room trench and labyrinth exits. The roof top was made inaccessible. The present study is an attempt to evaluate the neutron and associated capture gamma transport through the bulk shields for the complete geometry and materials of the NG-Hall using Monte Carlo (MC) codes MCNP and FLUKA. The neutron source terms of D-D, D-T and D-Be reactions are considered in the simulations. The effect of additional shielding proposed has been demonstrated through the simulations carried out with the consideration of the additional shielding for D-Be neutron source term. The results MC simulations using two different codes are found to be consistent with each other for neutron dose rate estimates. However, deviation up to 28% is noted between these two codes at few locations for capture gamma dose rate estimates. Overall, the dose rates estimated by MC simulations including additional shields shows that all the locations surrounding the hall satisfy the full occupancy criteria for all three types of sources. Additionally, the dose rates due to direct transmission of primary neutrons estimated by FLUKA are compared with the values calculated using the formula given in NCRP-51 which shows deviations up to 50% with each other. The details of MC simulations and NCRP-51 methodology for the estimation of primary neutron dose rate along with the results are presented in this paper. (author)

  20. A single-shot nanosecond neutron pulsed technique for the detection of fissile materials

    Science.gov (United States)

    Gribkov, V.; Miklaszewski, R. A.; Chernyshova, M.; Scholz, M.; Prokopovicz, R.; Tomaszewski, K.; Drozdowicz, K.; Wiacek, U.; Gabanska, B.; Dworak, D.; Pytel, K.; Zawadka, A.

    2012-07-01

    A novel technique with the potential of detecting hidden fissile materials is presented utilizing the interaction of a single powerful and nanosecond wide neutron pulse with matter. The experimental system is based on a Dense Plasma Focus (DPF) device as a neutron source generating pulses of almost mono-energetic 2.45 MeV and/or 14.0 MeV neutrons, a few nanoseconds in width. Fissile materials, consisting of heavy nuclei, are detected utilizing two signatures: firstly by measuring those secondary fission neutrons which are faster than the elastically scattered 2.45 MeV neutrons of the D-D reaction in the DPF; secondly by measuring the pulses of the slower secondary fission neutrons following the pulse of the fast 14 MeV neutrons from the D-T reaction. In both cases it is important to compare the measured spectrum of the fission neutrons induced by the 2.45 MeV or 14 MeV neutron pulse of the DPF with theoretical spectra obtained by mathematical simulation. Therefore, results of numerical modelling of the proposed system, using the MCNP5 and the FLUKA codes are presented and compared with experimental data.

  1. The pilot experimental study of 14 MeV fast neutron digital radiography

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    14 MeV Fast neutrons has good penetrability and the 14 MeV fast neutron radiography can meet the need of Non-Destructive Test of the structure and lacuna of heavy-massive sample, whose shell is made of heavy metal and in which there are some hydrogen materials, and the study of fast neutron digital radiography just begins in China. By the use of a D-T accelerator, a digital imaging system made up of a fast neutron scintillation screen made of ZnS(Ag) and polypropylene, lens and a scientific grade CCD, the experimental study of fast neutron radiography has been done between 4.3×1010-6.8×1010 n/s of neutron yield. Some 14 MeV fast neutron digital radiographs have been gotten. According to experimental radiographs and their data, the performance of the fast neutron scintillation screen and the basic characters of 14 MeV fast neutron radiography are analyzed, and it is helpful for the further research.

  2. The pilot experimental study of 14 MeV fast neutron digital radiography

    Institute of Scientific and Technical Information of China (English)

    TANG Bin; ZHOU ChangGen; HUO HeYong; WU Yang; LIU Bin; LOU BenChao; SUN Yong

    2009-01-01

    14 MeV Fast neutrons has good penetrability and the 14 MeV fast neutron radiography can meet the need of Non-Destructive Test of the structure and lacuna of heavy-massive sample,whose shell is made of heavy metal and in which there are some hydrogen materials,and the study of fast neutron digital radiography just begins in China.By the use of a D-T accelerator,a digital imaging system made up of a fast neutron scintillation screen made of ZnS(Ag) and polypropylene,lens and a scientific grade CCD,the experimental study of fast neutron radiography has been done between 4.3×1010-6.8×1010 n/s of neutron yield.Some 14 MeV fast neutron digital radiographs have been gotten.According to ex-perimental radiographs and their data,the performance of the fast neutron scintillation screen and the basic characters of 14 MeV fast neutron radiography are analyzed,and it is helpful for the further re-search.

  3. Ecosystem-management-based Management Models of Fast-growing and High-yield Plantation and Its Eco-economic Benefits Analysis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The paper expounded the basic concept and principles of ecosystem management,and analyzed the state and trend of industrial plantation ecosystem management in other countries.Based on the analysis of typical case studies,the eco-economic benefits were evaluated for the management models of fast-growing and high-yield plantations.

  4. Neutron anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Bacon, G.E. [Univ. of Sheffield (United Kingdom)

    1994-12-31

    The familiar extremes of crystalline material are single-crystals and random powders. In between these two extremes are polycrystalline aggregates, not randomly arranged but possessing some preferred orientation and this is the form taken by constructional materials, be they steel girders or the bones of a human or animal skeleton. The details of the preferred orientation determine the ability of the material to withstand stress in any direction. In the case of bone the crucial factor is the orientation of the c-axes of the mineral content - the crystals of the hexagonal hydroxyapatite - and this can readily be determined by neutron diffraction. In particular it can be measured over the volume of a piece of bone, utilizing distances ranging from 1mm to 10mm. The major practical problem is to avoid the intense incoherent scattering from the hydrogen in the accompanying collagen; this can best be achieved by heat-treatment and it is demonstrated that this does not affect the underlying apatite. These studies of bone give leading anatomical information on the life and activities of humans and animals - including, for example, the life history of the human femur, the locomotion of sheep, the fracture of the legs of racehorses and the life-styles of Neolithic tribes. We conclude that the material is placed economically in the bone to withstand the expected stresses of life and the environment. The experimental results are presented in terms of the magnitude of the 0002 apatite reflection. It so happens that for a random powder the 0002, 1121 reflections, which are neighboring lines in the powder pattern, are approximately equal in intensity. The latter reflection, being of manifold multiplicity, is scarcely affected by preferred orientation so that the numerical value of the 0002/1121 ratio serves quite accurately as a quantitative measure of the degree of orientation of the c-axes in any chosen direction for a sample of bone.

  5. Design of Shielding and Filtering System for D-T Neutron Tube%D-T中子管屏蔽过滤系统设计

    Institute of Scientific and Technical Information of China (English)

    赵括; 过惠平; 王洪超; 魏志浩; 吕宁; 鲍卫红

    2014-01-01

    中子监测是辐射场所监测的常规项目之一,提高辐射监测仪的标校技术在确保监测质量方面显得尤为重要,针对辐射监测仪受现场和工作条件限制不能上溯至较高的国家计量标准进行校准的问题,提出了贮存场所辐射监测仪现场标校技术研究.为获得单能中子源,实现涉核场所的现场标校,分析了DT中子管的结构特点和中子源特点,采用蒙特卡罗方法模拟了典型材料与不同能量中子的作用效果,将多层屏蔽材料进行组合优化,得到了屏蔽中子管中子源的最佳方案.在此基础上,设计了锥形准直过滤结构,利用蒙特卡罗方法模拟了准直结构作用效果.结果表明,锥形准直过滤结构可获得单色性能较好的14.1 MeV、0.18 MeV和热中子等单能中子,为现场标校提供了多个单能源.

  6. Fast neutron spectroscopy with tensioned metastable fluid detectors

    Science.gov (United States)

    Grimes, T. F.; Taleyarkhan, R. P.

    2016-09-01

    This paper describes research into development of a rapid-turnaround, neutron-spectroscopy capable (gamma-beta blind), high intrinsic efficiency sensor system utilizing the tensioned metastable fluid detector (TMFD) architecture. The inability of prevailing theoretical models (developed successfully for the classical bubble chamber) to adequately predict detection thresholds for tensioned metastable fluid conditions is described. Techniques are presented to overcome these inherent shortcomings, leading thereafter, to allow successful neutron spectroscopy using TMFDs - via the newly developed Single Atom Spectroscopy (SAS) approach. SAS also allows for a unique means for rapidly determining neutron energy thresholds with TMFDs. This is accomplished by simplifying the problem of determining Cavitation Detection Events (CDEs) arising from neutron interactions with one in which several recoiling atom species contribute to CDEs, to one in which only one dominant recoil atom need be considered. The chosen fluid is Heptane (C7H16) for which only recoiling C atoms contribute to CDEs. Using the SAS approach, the threshold curve for Heptane was derived using isotope neutron source data, and then validated against experiments with mono-energetic (2.45/14 MeV) neutrons from D-D and D-T accelerators. Thereafter the threshold curves were used to produce the response matrix for various geometries. The response matrices were in turn combined with experimental data to recover the continuous spectra of fission (Cf-252) and (α,n) Pu-Be isotopic neutron sources via an unfolding algorithm. A generalized algorithm is also presented for performing neutron spectroscopy using any other TMFD fluid that meets the SAS approach assumptions.

  7. Fast neutron spectroscopy with tensioned metastable fluid detectors

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, T.F.; Taleyarkhan, R.P., E-mail: rusi@purdue.edu

    2016-09-11

    This paper describes research into development of a rapid-turnaround, neutron-spectroscopy capable (gamma-beta blind), high intrinsic efficiency sensor system utilizing the tensioned metastable fluid detector (TMFD) architecture. The inability of prevailing theoretical models (developed successfully for the classical bubble chamber) to adequately predict detection thresholds for tensioned metastable fluid conditions is described. Techniques are presented to overcome these inherent shortcomings, leading thereafter, to allow successful neutron spectroscopy using TMFDs – via the newly developed Single Atom Spectroscopy (SAS) approach. SAS also allows for a unique means for rapidly determining neutron energy thresholds with TMFDs. This is accomplished by simplifying the problem of determining Cavitation Detection Events (CDEs) arising from neutron interactions with one in which several recoiling atom species contribute to CDEs, to one in which only one dominant recoil atom need be considered. The chosen fluid is Heptane (C{sub 7}H{sub 16}) for which only recoiling C atoms contribute to CDEs. Using the SAS approach, the threshold curve for Heptane was derived using isotope neutron source data, and then validated against experiments with mono-energetic (2.45/14 MeV) neutrons from D-D and D-T accelerators. Thereafter the threshold curves were used to produce the response matrix for various geometries. The response matrices were in turn combined with experimental data to recover the continuous spectra of fission (Cf-252) and (α,n) Pu–Be isotopic neutron sources via an unfolding algorithm. A generalized algorithm is also presented for performing neutron spectroscopy using any other TMFD fluid that meets the SAS approach assumptions.

  8. Imaging with Scattered Neutrons

    OpenAIRE

    Ballhausen, H.; Abele, H.; Gaehler, R.; Trapp, M.; Van Overberghe, A.

    2006-01-01

    We describe a novel experimental technique for neutron imaging with scattered neutrons. These scattered neutrons are of interest for condensed matter physics, because they permit to reveal the local distribution of incoherent and coherent scattering within a sample. In contrast to standard attenuation based imaging, scattered neutron imaging distinguishes between the scattering cross section and the total attenuation cross section including absorption. First successful low-noise millimeter-re...

  9. Intense fusion neutron sources

    Science.gov (United States)

    Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

    2010-04-01

    The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 1015-1021 neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 1020 neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the neutron itself.

  10. International Neutron Radiography Newsletter

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1986-01-01

    At the First World Conference on Neutron Radiography i t was decided to continue the "Neutron Radiography Newsletter", published previously by J.P. Barton, as the "International Neutron Radiography Newsletter" (INRNL), with J.C. Doraanus as editor. The British Journal of Non-Destructive Testing...

  11. Advanced neutron absorber materials

    Science.gov (United States)

    Branagan, Daniel J.; Smolik, Galen R.

    2000-01-01

    A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

  12. Prototype Neutron Energy Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Mitchell, Sanjoy Mukhopadhyay, Richard Maurer, Ronald Wolff

    2010-06-16

    The project goals are: (1) Use three to five pressurized helium tubes with varying polyethylene moderators to build a neutron energy spectrometer that is most sensitive to the incident neutron energy of interest. Neutron energies that are of particular interest are those from the fission neutrons (typically around 1-2 MeV); (2) Neutron Source Identification - Use the neutron energy 'selectivity' property as a tool to discriminate against other competing processes by which neutrons are generated (viz. Cosmic ray induced neutron production [ship effect], [a, n] reactions); (3) Determine the efficiency as a function of neutron energy (response function) of each of the detectors, and thereby obtain the composite neutron energy spectrum from the detector count rates; and (4) Far-field data characterization and effectively discerning shielded fission source. Summary of the presentation is: (1) A light weight simple form factor compact neutron energy spectrometer ready to be used in maritime missions has been built; (2) Under laboratory conditions, individual Single Neutron Source Identification is possible within 30 minutes. (3) Sources belonging to the same type of origin viz., (a, n), fission, cosmic cluster in the same place in the 2-D plot shown; and (4) Isotopes belonging to the same source origin like Cm-Be, Am-Be (a, n) or Pu-239, U-235 (fission) do have some overlap in the 2-D plot.

  13. Limitations of 14 MeV neutron simulation techniques

    Science.gov (United States)

    Kley, W.; Bishop, G. R.; Sinha, A.

    1988-07-01

    A D-T fusion cycle produces five times more neutrons per unit of energy released than a fission cycle, with about twice the damage energy and the capability to produce ten times more hydrogen, helium and transmutation products than fission neutrons. They determine, together with other parameters, the lifetime of the construction materials for the low plasma-density fusion reactors (tokamak, tandem-mirror, etc.), which require a first wall. For the economie feasibility of fusion power reactors the first wall and blanket materials must withstand a dose approaching 300 to 400 dpa. Arguments are presented that demonstrate that today's simulation techniques using existing fission reactors and charged particle beams are excellent tools to study the underlying basic physical phenomena of the evolving damage structures but are not sufficient to provide a valid technological data base for the design of economie fusion power reactors. It is shown than an optimized spallation neutron source based on a continuous beam of 600 MeV, 6 mA protons is suitable to simulate first wall conditions. Comparing it with FMIT the 35 MeV, 100 mA D + -Li neutron source, we arrive at the following figure of merit: FM = {(dpa·volume) EURAC}/{(dpa·volume) FMIT} = {} = 111 reflecting the fact that the proton beam generates about 100 times more neutrons than the deuteron beam in FMIT for the same beam power.

  14. Concept of DT fuel cycle for a fusion neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Anan' ev, S.; Spitsyn, A.V.; Kuteev, B.V.; Cherkez, D.I. [NRC Kurchatov Institute, Moscow (Russian Federation); Shirnin, P.N.; Kazakovsky, N.T. [FSUE RFNC - VNIIEF, Sarov (Russian Federation)

    2015-03-15

    A concept of DT-fusion neutron source (FNS) with the neutron yield higher than 10{sup 18} neutrons per second is under design in Russia. Such a FNS is of interest for many applications: 1) basic and applied research (neutron scattering, etc); 2) testing the structural materials for fusion reactors; 3) control of sub-critical nuclear systems and 4) nuclear waste processing (including transmutation of minor actinides). This paper describes the fuel cycle concept of a compact fusion neutron source based on a small spherical tokamak (FNS-ST) with a MW range of DT fusion power and considers the key physics issues of this device. The major and minor radii are ∼0.5 and ∼0.3 m, magnetic field ∼1.5 T, heating power less than 15 MW and plasma current 1-2 MA. The system provides the fuel mixture with equal fractions of D and T (D:T = 1:1) for all FNS technology systems. (authors)

  15. Microstructured boron foil scintillating G-GEM detector for neutron imaging

    Science.gov (United States)

    Fujiwara, Takeshi; Bautista, Unico; Mitsuya, Yuki; Takahashi, Hiroyuki; Yamada, Norifumi L.; Otake, Yoshie; Taketani, Atsushi; Uesaka, Mitsuru; Toyokawa, Hiroyuki

    2016-12-01

    In this study, a new simple neutron imaging gaseous detector was successfully developed by combining a micro-structured 10B foil, a glass gas electron multiplier (G-GEM), and a mirror-lens-charge-coupled device (CCD)-camera system. The neutron imaging system consists of a chamber filled with Ar/CF4 scintillating gas mixture. Inside this system, the G-GEM is mounted for gas multiplication. The neutron detection in this system is based on the reaction between 10B and neutrons. A micro-structured 10B is developed to overcome the issue of low detection efficiency. Secondary electrons excite Ar/CF4 gas molecules, and high-yield visible photons are emitted from those excited gas molecules during the gas electron multiplication process in the G-GEM holes. These photons are easily detected by a mirror-lens-CCD-camera system. A neutron radiograph is then simply formed. We obtain the neutron images of different materials with a compact accelerator-driven neutron source. We confirm that the new scintillating G-GEM-based neutron imager works properly with low gamma ray sensitivity and exhibits a good performance as a new simple digital neutron imaging device.

  16. An alpha particle detector for a portable neutron generator for the Nuclear Materials Identification System (NMIS)

    Science.gov (United States)

    Hausladen, P. A.; Neal, J. S.; Mihalczo, J. T.

    2005-12-01

    A recoil alpha particle detector has been developed for use in a portable neutron generator. The associated particle sealed tube neutron generator (APSTNG) will be used as an interrogation source for the Nuclear Materials Identification System (NMIS). With the coincident emission of 14.1 MeV neutrons and 3.5 MeV alpha particles produced by the D-T reaction, alpha detection determines the time and direction of the neutrons of interest for subsequent use as an active nuclear materials interrogation source. The alpha particle detector uses a ZnO(Ga) scintillator coating applied to a fiber optic face plate. Gallium-doped zinc oxide is a fast (inorganic scintillator with a high melting point (1975 °C). One detector has been installed in an APSTNG and is currently being tested. Initial results include a measured efficiency for 3.5 MeV alphas of 90%.

  17. Proton recoil telescope based on diamond detectors for measurement of fusion neutrons

    CERN Document Server

    Caiffi, B; Ripani, M; Pillon, M; Taiuti, M

    2015-01-01

    Diamonds are very promising candidates for the neutron diagnostics in harsh environments such as fusion reactor. In the first place this is because of their radiation hardness, exceeding that of Silicon by an order of magnitude. Also, in comparison to the standard on-line neutron diagnostics (fission chambers, silicon based detectors, scintillators), diamonds are less sensitive to $\\gamma$ rays, which represent a huge background in fusion devices. Finally, their low leakage current at high temperature suppresses the detector intrinsic noise. In this talk a CVD diamond based detector has been proposed for the measurement of the 14 MeV neutrons from D-T fusion reaction. The detector was arranged in a proton recoil telescope configuration, featuring a plastic converter in front of the sensitive volume in order to induce the (n,p) reaction. The segmentation of the sensitive volume, achieved by using two crystals, allowed to perform measurements in coincidence, which suppressed the neutron elastic scattering backg...

  18. Integration of an advanced sealed-tube neutron generator into a mobile neutron radiology system and resulting performance

    Science.gov (United States)

    Dance, William E.; Cluzeau, Serge; Mast, Hans-Ulrich

    1991-05-01

    The first DIANE ∗ neutron radiology system is being prepared for operation in the IABG laboratories in Ottobrunn (Germany). It utilizes a new D-T generator, designated GENIE 46, developed by SODERN (France) for this application. The generator is being integrated into an upgraded LTV-produced mobile neutron radiology system suitable for practical nonreactor inspection of components and structures. The maximum output of the present version of the GENIE 46 is 5 × 10 11 n s -1 (14 MeV) with less than 10 mA ion beam current at 225 kV. Tube lifetime at maximum output is approximately 500 h, while at 10 11 n s -1 the tube is designed for a lifetime of 1500 h. The geometry of the neutron tube, VHV connectors, ion source power supply, and cooling tubes comprises a cannister designed to be compatible with the 10-in. diameter opening in the LTV moderator/collimator assembly. 3-D Monte Carlo neutron/photon transport simulations of the new integrated radiology system operation have been performed by IABG. The calculations predict a thermal neutron flux at the collimator exit ( {L}/{D} = 13) of φth(0 ≤ En ≤ 0.3 eV) = 1.2 × 10 5 n cm -2 s -1. Comparisons of this value and other Monte Carlo results with actual performance will be made in the near future with the accrual of operational data.

  19. Testing a new NIF neutron time-of-flight detector with a bibenzyl scintillator on OMEGA.

    Science.gov (United States)

    Glebov, V Yu; Forrest, C; Knauer, J P; Pruyne, A; Romanofsky, M; Sangster, T C; Shoup, M J; Stoeckl, C; Caggiano, J A; Carman, M L; Clancy, T J; Hatarik, R; McNaney, J; Zaitseva, N P

    2012-10-01

    A new neutron time-of-flight (nTOF) detector with a bibenzyl crystal as a scintillator has been designed and manufactured for the National Ignition Facility (NIF). This detector will replace a nTOF20-Spec detector with an oxygenated xylene scintillator currently operational on the NIF to improve the areal-density measurements. In addition to areal density, the bibenzyl detector will measure the D-D and D-T neutron yield and the ion temperature of indirect- and direct-drive-implosion experiments. The design of the bibenzyl detector and results of tests on the OMEGA Laser System are presented.

  20. Testing a new NIF neutron time-of-flight detector with a bibenzyl scintillator on OMEGA

    Energy Technology Data Exchange (ETDEWEB)

    Glebov, V. Yu.; Forrest, C.; Knauer, J. P.; Pruyne, A.; Romanofsky, M.; Sangster, T. C.; Shoup, M. J. III; Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299 (United States); Caggiano, J. A.; Carman, M. L.; Clancy, T. J.; Hatarik, R.; McNaney, J.; Zaitseva, N. P. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2012-10-15

    A new neutron time-of-flight (nTOF) detector with a bibenzyl crystal as a scintillator has been designed and manufactured for the National Ignition Facility (NIF). This detector will replace a nTOF20-Spec detector with an oxygenated xylene scintillator currently operational on the NIF to improve the areal-density measurements. In addition to areal density, the bibenzyl detector will measure the D-D and D-T neutron yield and the ion temperature of indirect- and direct-drive-implosion experiments. The design of the bibenzyl detector and results of tests on the OMEGA Laser System are presented.

  1. Neutron scattering. Experiment manuals

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2010-07-01

    The following topics are dealt with: The thermal triple axis spectrometer PUMA, the high-resolution powder diffractometer SPODI, the hot single-crystal diffractometer HEiDi for structure analysis with neutrons, the backscattering spectrometer SPHERES, neutron polarization analysis with tht time-of-flight spectrometer DNS, the neutron spin-echo spectrometer J-NSE, small-angle neutron scattering with the KWS-1 and KWS-2 diffractometers, the very-small-angle neutron scattering diffractrometer with focusing mirror KWS-3, the resonance spin-echo spectrometer RESEDA, the reflectometer TREFF, the time-of-flight spectrometer TOFTOF. (HSI)

  2. Grazing Incidence Neutron Optics

    Science.gov (United States)

    Gubarev, Mikhail V. (Inventor); Ramsey, Brian D. (Inventor); Engelhaupt, Darell E. (Inventor)

    2013-01-01

    Neutron optics based on the two-reflection geometries are capable of controlling beams of long wavelength neutrons with low angular divergence. The preferred mirror fabrication technique is a replication process with electroform nickel replication process being preferable. In the preliminary demonstration test an electroform nickel optics gave the neutron current density gain at the focal spot of the mirror at least 8 for neutron wavelengths in the range from 6 to 20.ANG.. The replication techniques can be also be used to fabricate neutron beam controlling guides.

  3. Neutron/gamma dose separation by the multiple-ion-chamber technique

    Energy Technology Data Exchange (ETDEWEB)

    Goetsch, S.J.

    1983-01-01

    Many mixed n/..gamma.. dosimetry systems rely on two dosimeters, one composed of a tissue-equivalent material and the other made from a non-hydrogenous material. The paired chamber technique works well in fields of neutron radiation nearly identical in spectral composition to that in which the dosimeters were calibrated. However, this technique is drastically compromised in phantom due to the degradation of the neutron spectrum. The three-dosimeter technique allows for the fall-off in neutron sensitivity of the two non-hydrogenous dosimeters. Precise and physically meaningful results were obtained with this technique with a D-T source in air and in phantom and with simultaneous D-T neutron and /sup 60/Co gamma ray irradiation in air. The MORSE-CG coupled n/..gamma.. three-dimensional Monte Carlo code was employed to calculate neutron and gamma doses in a water phantom. Gamma doses calculated in phantom with this code were generally lower than corresponding ion chamber measurements. This can be explained by the departure of irradiation conditions from ideal narrow-beam geometry. 97 references.

  4. Advances in neutron tomography

    Indian Academy of Sciences (India)

    W Treimer

    2008-11-01

    In the last decade neutron radiography (NR) and tomography (NCT) have experienced a number of improvements, due to the well-known properties of neutrons interacting with matter, i.e. the low attenuation by many materials, the strong attenuation by hydrogenous constituent in samples, the wavelength-dependent attenuation in the neighbourhood of Bragg edges and due to better 2D neutron detectors. So NR and NCT were improved by sophisticated techniques that are based on the attenuation of neutrons or on phase changes of the associated neutron waves if they pass through structured materials. Up to now the interaction of the neutron spin with magnetic fields in samples has not been applied to imaging techniques despite the fact that it was proposed many years ago. About ten years ago neutron depolarization as imaging signal for neutron radiography or tomography was demonstrated and in principle it works. Now one can present much improved test experiments using polarized neutrons for radiographic imaging. For this purpose the CONRAD instrument of the HMI was equipped with polarizing and analysing benders very similar to conventional scattering experiments using polarized neutrons. Magnetic fields in different coils and in samples (superconductors) at low temperatures could be visualized. In this lecture a summary about standard signals (attenuation) and the more `sophisticated' imaging signals as refraction, small angle scattering and polarized neutrons will be given.

  5. Neutronic Reactor Shield

    Science.gov (United States)

    Fermi, Enrico; Zinn, Walter H.

    The argument of the present Patent is a radiation shield suitable for protection of personnel from both gamma rays and neutrons. Such a shield from dangerous radiations is achieved to the best by the combined action of a neutron slowing material (a moderator) and a neutron absorbing material. Hydrogen is particularly effective for this shield since it is a good absorber of slow neutrons and a good moderator of fast neutrons. The neutrons slowed down by hydrogen may, then, be absorbed by other materials such as boron, cadmium, gadolinium, samarium or steel. Steel is particularly convenient for the purpose, given its effectiveness in absorbing also the gamma rays from the reactor (both primary gamma rays and secondary ones produced by the moderation of neutrons). In particular, in the present Patent a shield is described, made of alternate layers of steel and Masonite (an hydrolized ligno-cellulose material). The object of the present Patent is not discussed in any other published paper.

  6. Detection of buried explosives using portable neutron sources with nanosecond timing

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, A.V. E-mail: apl@atom.nw.ru; Evsenin, A.V.; Gorshkov, I.Yu.; Osetrov, O.I.; Vakhtin, D.N

    2004-07-01

    Significant reduction of time needed to identify hidden explosives and other hazardous materials by the 'neutron in, gamma out' method has been achieved by introducing timed (nanosecond) neutron sources--the so-called nanosecond neutron analysis technique. Prototype mobile device for explosives' detection based on a timed (nanosecond) isotopic {sup 252}Cf neutron source has been created. The prototype is capable of identifying 400 g of hidden explosives in 10 min. Tests have been also made with a prototype device using timed (nanosecond) neutron source based on a portable D-T neutron generator with built-in segmented detector of accompanying {alpha}-particles. The presently achieved intensity of the neutron generator is 5x10{sup 7} n/s into 4{pi}, with over 10{sup 6} of these neutrons being correlated with {alpha}-particles detected by the built-in {alpha}-particle detector. Results of measurements with an anti-personnel landmine imitator are presented.

  7. Producing Technique of High Yield and Quality Pigment Marigold%高产优质色素万寿菊生产技术

    Institute of Scientific and Technical Information of China (English)

    张红

    2015-01-01

    For meeting the requirement of scale and industrialization production, it selected pigment marigold variety with high yield, high quality, and strong adverse resistance, summarized a set of scientific and complete producing techniques for marigold, and applied in practice, in order to realize stable and high yield for marigold in Faku area.%为适应规模化、工厂化生产的需要,优选出适合法库地区的高产、优质、抗逆性强的色素万寿菊品种,总结一整套科学、完善的万寿菊生产技术措施,并进行推广应用,以实现法库地区万寿菊的高产稳产.

  8. Molecular characterization of Salmonella Paratyphi B dT+ and Salmonella Heidelberg from poultry and retail chicken meat in Colombia by pulsed-field gel electrophoresis

    Science.gov (United States)

    Salmonella Paratyphi B dT+ variant (also termed Salmonella Java) and Salmonella Heidelberg are human pathogens frequently isolated from poultry. As a step towards implementing the Colombian Integrated Program for Antimicrobial Resistant Surveillance (COIPARS), this study characterized molecular patt...

  9. High-yield cultivation techniques of large-leaved water spinach(Ipomoea aquatica Forsk)%大叶空心菜高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    叶敏

    2015-01-01

    总结大叶空心菜高产栽培技术,主要包括播种育苗、定植、田间管理、病虫害防治、采收等方面内容。%High-yield cultivation techniques of large-leaved water spinach was summarized,mainly including culture of see-ding,field planting,field management,control of diseases and pests,harvesting and other aspects.

  10. Progress Towards Genetics and Breeding for Minor Genes Based Resistance to Ug99 and Other Rusts in CIMMYT High-Yielding Spring Wheat

    Institute of Scientific and Technical Information of China (English)

    Ravi Prakash Singh; Sybil Herrera-Foessel; Julio Huerta-Espino; Sukhwinder Singh; Sridhar Bhavani; Caixia Lan; and Bhoja Raj Basnet

    2014-01-01

    Wheat rusts continue to cause signiifcant losses worldwide despite major efforts given to their genetic control. This is due to frequent evolution and selection of virulence in pathogen overcoming the deployed race-speciifc resistance genes. Although the life of effective race-speciifc resistance genes can be prolonged by using gene combinations, an alternative approach being implemented at CIMMYT is to deploy varieties that posses adult plant resistance (APR) based on combinations of minor, slow rusting genes. When present alone, the APR genes do not confer adequate resistance especially under high disease pressure; however, combinations of 4 or 5 minor genes usually result in “near-immunity” or a high level of resistance. Although only a few APR genes are catalogued, various APR QTLs are now known and could lead to further characterization of additional genes. Four characterized genes have pleiotropic effects in conferring partial APR to all 3 rusts and powdery mildew, thus simplifying the task of breeding wheat varieties that are resistant to multiple diseases. Signiifcant progress was made recently in developing high-yielding wheat germplasm that possesses high levels of APR to all three rusts by implementing a Mexico-Kenya shuttle breeding scheme. Parents with APR to Ug99 were hybridized with high-yielding parents that had adequate to high levels of APR to leaf rust and yellow rust. Segregating populations and advanced lines from these crosses were selected under high rust pressures in Mexico (leaf rust and yellow rust) and Kenya (Ug99 stem rust and yellow rust) to identify high-yielding progenies that possess high to adequate APR to all three rusts. International distribution of these high-yielding wheats is underway through CIMMYT international yield trials and screening nurseries. It is expected that several wheat varieties with APR to three rusts will be released and grown in various countries in the near-future that will allow determining the

  11. Evaluation on the High Yielding, Stability and Comprehensive Performances of Check Cultivars in National Cotton Regional Trials in the Yangtze River Valley

    Institute of Scientific and Technical Information of China (English)

    Shiqiao JIN; Naiyin XU

    2014-01-01

    Objective] This study was to analyze the high yielding, stability, adaptabil-ity and main characteristics of check cultivars in national cotton regional trials in the Yangtze River Val ey in 2000-2013, with the aim to provide theoretical basis for the reasonable selection of check cultivars for cotton regional trials. [Method] GGE biplot analysis method was used to carry out the intensive analysis and comprehensive comparisons on the performances and differences of the 9 major characters of check cultivars, namely, lint cotton yield , stability, and other main traits including bol weight, bol number, lint percentage, fiber length, fiber strength, micronaire val-ue, plant height and seed index. [Result] Ezamian 10 was suitable in the majority of cotton planting regions in the Yangtze River Val ey, with the best high yielding abili-ty and perfect yield stability. The yielding ability of Xiangzamian 8 ranked the sec-ond, but its stability was the poorest. Xiangzamian 8 was of the specific adaptive cultivar with relatively good performance in high yielding but the poorest stability. The suitable planting areas of Xiangzamian 8 were limited to the cotton planting re-gion around Dongting Lake in Hunan province, Poyang Lake in Jiangxi Province, the Coastal region in Jiangsu Province and Wuhan district in Hubei Province. Xi-angzamian 2 performanced poorer in both yielding and stability, while Simian 3 ranked first in stability but the last in yielding ability. The dominant character of Xi-angzamian 8 and Xiangzamian 2 were high cotton plants and big bol s. Simian 3 performanced super in lint percentage and fiber length. Ezamian 10 was strong in cotton bol formation ability, lint cotton yielding, fiber strength and seed size, as wel as high micronaire value. [Conclusion] The outstanding performance of Ezamian 10 in high and stable yield in the Yangtze River Val ey in recent years has effectively promoted the high yielding ability of candidate varieties in cotton regional

  12. High-yield production of a stable Vero cell-based vaccine candidate against the highly pathogenic avian influenza virus H5N1

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Fangye; Zhou, Jian; Ma, Lei; Song, Shaohui; Zhang, Xinwen; Li, Weidong; Jiang, Shude [No. 5, Department of Bioproducts, Institute of Medical Biology, Chinese Academy of Medical Science and Pecking Union Medical College, Jiaoling Avenue 935, Kunming, Yunnan Province 650102, People' s Republic of China (China); Wang, Yue, E-mail: euy-tokyo@umin.ac.jp [National Institute for Viral Disease Control and Prevention, China Center for Disease Control and Prevention, Yingxin Lane 100, Xicheng District, Beijing 100052, People' s Republic of China (China); Liao, Guoyang, E-mail: liaogy@21cn.com [No. 5, Department of Bioproducts, Institute of Medical Biology, Chinese Academy of Medical Science and Pecking Union Medical College, Jiaoling Avenue 935, Kunming, Yunnan Province 650102, People' s Republic of China (China)

    2012-05-18

    Highlights: Black-Right-Pointing-Pointer Vero cell-based HPAI H5N1 vaccine with stable high yield. Black-Right-Pointing-Pointer Stable high yield derived from the YNVa H3N2 backbone. Black-Right-Pointing-Pointer H5N1/YNVa has a similar safety and immunogenicity to H5N1delta. -- Abstract: Highly pathogenic avian influenza (HPAI) viruses pose a global pandemic threat, for which rapid large-scale vaccine production technology is critical for prevention and control. Because chickens are highly susceptible to HPAI viruses, the supply of chicken embryos for vaccine production might be depleted during a virus outbreak. Therefore, developing HPAI virus vaccines using other technologies is critical. Meeting vaccine demand using the Vero cell-based fermentation process has been hindered by low stability and yield. In this study, a Vero cell-based HPAI H5N1 vaccine candidate (H5N1/YNVa) with stable high yield was achieved by reassortment of the Vero-adapted (Va) high growth A/Yunnan/1/2005(H3N2) (YNVa) virus with the A/Anhui/1/2005(H5N1) attenuated influenza vaccine strain (H5N1delta) using the 6/2 method. The reassorted H5N1/YNVa vaccine maintained a high hemagglutination (HA) titer of 1024. Furthermore, H5N1/YNVa displayed low pathogenicity and uniform immunogenicity compared to that of the parent virus.

  13. Status of spallation neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    Existing and planned facilities using proton accelerator driven spallation neutron source are reviewed. These include new project of neutron science proposed from Japan Atomic Energy Research Institute. The present status of facility requirement and accelerator technology leads us to new era of neutron science such as neutron scattering research and nuclear transmutation study using very intense neutron source. (author)

  14. Reaction-in-Flight Neutrons as a Signature for Shell Mixing in NIF capsules

    CERN Document Server

    Hayes, A C; Grim, G P; Jungman, Gerard; Wilhelmy, J B

    2009-01-01

    We present analytic calculations and results from computational simulations showing that reaction-in-flight (RIF) neutrons act as a robust indicator for mixing of the ablator shell material into the fuel in DT capsules designed for the National Ignition Facility. The sensitivity of RIF neutrons to hydrodynamical mixing arises through the dependence of RIF production on charged-particle stopping lengths in the mixture of DT fuel and ablator material. Since the stopping power in the plasma is a sensitive function of the electron temperature and density, it is also sensitive to mix. RIF production scales approximately inversely with the degree of mixing taking place, and the ratio of RIF to downscattered neutrons provides a measure of the mix fraction and/or the mixing length. For sufficiently high-yield capsules, where spatially resolved RIF images may be possible, neutron imaging could be used to map RIF images into detailed mix images.

  15. Manifold learning for shape guided segmentation of cardiac boundaries: application to 3D+t cardiac MRI.

    Science.gov (United States)

    Eslami, Abouzar; Yigitsoy, Mehmet; Navab, Nassir

    2011-01-01

    In this paper we propose a new method for shape guided segmentation of cardiac boundaries based on manifold learning of the shapes represented by the phase field approximation of the Mumford-Shah functional. A novel distance is defined to measure the similarity of shapes without requiring deformable registration. Cardiac motion is compensated and phases are mapped into one reference phase, that is the end of diastole, to avoid time warping and synchronization at all cardiac phases. Non-linear embedding of these 3D shapes extracts the manifold of the inter-subject variation of the heart shape to be used for guiding the segmentation for a new subject. For validation the method is applied to a comprehensive dataset of 3D+t cardiac Cine MRI from normal subjects and patients.

  16. An AC phase measuring interferometer for measuring dn/dT of fused silica and calcium fluoride at 193 nm

    Energy Technology Data Exchange (ETDEWEB)

    Shagam, R.N.

    1998-09-01

    A novel method for the measurement of the change in index of refraction vs. temperature (dn/dT) of fused silica and calcium fluoride at the 193 nm wavelength has been developed in support of thermal modeling efforts for the development of 193 nm-based photolithographic exposure tools. The method, based upon grating lateral shear interferometry, uses a transmissive linear grating to divide a 193 nm laser beam into several beam paths by diffraction which propagate through separate identical material samples. One diffracted order passing through one sample overlaps the undiffracted beam from a second sample and forms interference fringes dependent upon the optical path difference between the two samples. Optical phase delay due to an index change from heating one of the samples causes the interference fringes to change sinusoidally with phase. The interferometer also makes use of AC phase measurement techniques through lateral translation of the grating. Results for several samples of fused silica and calcium fluoride are demonstrated.

  17. Poly(dA:dT-rich DNAs are highly flexible in the context of DNA looping.

    Directory of Open Access Journals (Sweden)

    Stephanie Johnson

    Full Text Available Large-scale DNA deformation is ubiquitous in transcriptional regulation in prokaryotes and eukaryotes alike. Though much is known about how transcription factors and constellations of binding sites dictate where and how gene regulation will occur, less is known about the role played by the intervening DNA. In this work we explore the effect of sequence flexibility on transcription factor-mediated DNA looping, by drawing on sequences identified in nucleosome formation and ligase-mediated cyclization assays as being especially favorable for or resistant to large deformations. We examine a poly(dA:dT-rich, nucleosome-repelling sequence that is often thought to belong to a class of highly inflexible DNAs; two strong nucleosome positioning sequences that share a set of particular sequence features common to nucleosome-preferring DNAs; and a CG-rich sequence representative of high G+C-content genomic regions that correlate with high nucleosome occupancy in vivo. To measure the flexibility of these sequences in the context of DNA looping, we combine the in vitro single-molecule tethered particle motion assay, a canonical looping protein, and a statistical mechanical model that allows us to quantitatively relate the looping probability to the looping free energy. We show that, in contrast to the case of nucleosome occupancy, G+C content does not positively correlate with looping probability, and that despite sharing sequence features that are thought to determine nucleosome affinity, the two strong nucleosome positioning sequences behave markedly dissimilarly in the context of looping. Most surprisingly, the poly(dA:dT-rich DNA that is often characterized as highly inflexible in fact exhibits one of the highest propensities for looping that we have measured. These results argue for a need to revisit our understanding of the mechanical properties of DNA in a way that will provide a basis for understanding DNA deformation over the entire range of

  18. Neutron sources and applications

    Energy Technology Data Exchange (ETDEWEB)

    Price, D.L. [ed.] [Argonne National Lab., IL (United States); Rush, J.J. [ed.] [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1994-01-01

    Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.

  19. Prototype Stilbene Neutron Collar

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, M. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shumaker, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Snyderman, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Verbeke, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wong, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-26

    A neutron collar using stilbene organic scintillator cells for fast neutron counting is described for the assay of fresh low enriched uranium (LEU) fuel assemblies. The prototype stilbene collar has a form factor similar to standard He-3 based collars and uses an AmLi interrogation neutron source. This report describes the simulation of list mode neutron correlation data on various fuel assemblies including some with neutron absorbers (burnable Gd poisons). Calibration curves (doubles vs 235U linear mass density) are presented for both thermal and fast (with Cd lining) modes of operation. It is shown that the stilbene collar meets or exceeds the current capabilities of He-3 based neutron collars. A self-consistent assay methodology, uniquely suited to the stilbene collar, using triples is described which complements traditional assay based on doubles calibration curves.

  20. The DIORAMA Neutron Emitter

    Energy Technology Data Exchange (ETDEWEB)

    Terry, James Russell [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-05

    Emission of neutrons in a given event is modeled by the DioramaEmitterNeutron object, a subclass of the abstract DioramaEmitterModule object. The GenerateEmission method of this object is the entry point for generation of a neutron population for a given event. Shown in table 1, this method requires a number of parameters to be defined in the event definition.

  1. A conceptual design of a beam-shaping assembly for boron neutron capture therapy based on deuterium-tritium neutron generators.

    Science.gov (United States)

    Martín, Guido; Abrahantes, Arian

    2004-05-01

    A conceptual design of a beam-shaping assembly for boron neutron capture therapy using deuterium-tritium accelerator based neutrons source is developed. Calculations based on a simple geometry model for the radiation transport are initially performed to estimate the assembly materials and their linear dimensions. Afterward, the assembly geometry is produced, optimized and verified. In order to perform these calculations the general-purpose MCNP code is used. Irradiation time and therapeutic gain are utilized as beam assessment parameters. Metallic uranium and manganese are successfully tested for fast-to-epithermal neutron moderation. In the present beam-shaping assembly proposal, the therapeutic gain is improved by 23% and the accelerator current required for a fixed irradiation period is reduced by six times compared to previous proposals based on the same D-T reaction.

  2. Neutron scattering. Experiment manuals

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2014-07-01

    The following topics are dealt with: The thermal triple-axis spectrometer PUMA, the high-resolution powder diffractometer SPODI, the hot-single-crystal diffractometer HEiDi, the three-axis spectrometer PANDA, the backscattering spectrometer SPHERES, the DNS neutron-polarization analysis, the neutron spin-echo spectrometer J-NSE, small-angle neutron scattering at KWS-1 and KWS-2, a very-small-angle neutron scattering diffractometer with focusing mirror, the reflectometer TREFF, the time-of-flight spectrometer TOFTOF. (HSI)

  3. Neutron-emission measurements at a white neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Haight, Robert C [Los Alamos National Laboratory

    2010-01-01

    Data on the spectrum of neutrons emittcd from neutron-induced reactions are important in basic nuclear physics and in applications. Our program studies neutron emission from inelastic scattering as well as fission neutron spectra. A ''white'' neutron source (continuous in energy) allows measurements over a wide range of neutron energies all in one experiment. We use the tast neutron source at the Los Alamos Neutron Science Center for incident neutron energies from 0.5 MeV to 200 MeV These experiments are based on double time-of-flight techniques to determine the energies of the incident and emitted neutrons. For the fission neutron measurements, parallel-plate ionization or avalanche detectors identify fission in actinide samples and give the required fast timing pulse. For inelastic scattering, gamma-ray detectors provide the timing and energy spectroscopy. A large neutron-detector array detects the emitted neutrons. Time-of-flight techniques are used to measure the energies of both the incident and emitted neutrons. Design considerations for the array include neutron-gamma discrimination, neutron energy resolution, angular coverage, segmentation, detector efficiency calibration and data acquisition. We have made preliminary measurements of the fission neutron spectra from {sup 235}U, {sup 238}U, {sup 237}Np and {sup 239}Pu. Neutron emission spectra from inelastic scattering on iron and nickel have also been investigated. The results obtained will be compared with evaluated data.

  4. Beyond Californium-A Neutron Generator Alternative for Dosimetry and Instrument Calibration in the U.S.

    Science.gov (United States)

    Piper, Roman K; Mozhayev, Andrey V; Murphy, Mark K; Thompson, Alan K

    2017-09-01

    Evaluations of neutron survey instruments, area monitors, and personal dosimeters rely on reference neutron radiations, which have evolved from the heavy reliance on (α,n) sources to a shared reliance on (α,n) and the spontaneous fission neutrons of californium-252 (Cf). Capable of producing high dose equivalent rates from an almost point source geometry, the characteristics of Cf are generally more favorable when compared to the use of (α,n) and (γ,n) sources or reactor-produced reference neutron radiations. Californium-252 is typically used in two standardized configurations: unmoderated, to yield a fission energy spectrum; or with the capsule placed within a heavy-water moderating sphere to produce a softened spectrum that is generally considered more appropriate for evaluating devices used in nuclear power plant work environments. The U.S. Department of Energy Cf Loan/Lease Program, a longtime origin of affordable Cf sources for research, testing and calibration, was terminated in 2009. Since then, high-activity sources have become increasingly cost-prohibitive for laboratories that formerly benefited from that program. Neutron generators, based on the D-T and D-D fusion reactions, have become economically competitive with Cf and are recognized internationally as important calibration and test standards. Researchers from the National Institute of Standards and Technology and the Pacific Northwest National Laboratory are jointly considering the practicality and technical challenges of implementing neutron generators as calibration standards in the U.S. This article reviews the characteristics of isotope-based neutron sources, possible isotope alternatives to Cf, and the rationale behind the increasing favor of electronically generated neutron options. The evaluation of a D-T system at PNNL has revealed characteristics that must be considered in adapting generators to the task of calibration and testing where accurate determination of a dosimetric quantity is

  5. High yield cultivation techniques of cherry tomato in greenhouse%樱桃西红柿大棚高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    王道锋

    2015-01-01

    总结大棚樱桃西红柿高产栽培技术,主要包括品种选择、育苗、田块整理、大棚规格设置、定植、田间管理、病虫害防治、采收等方面内容。%This paper summarized high yield cultivation techniques of cherry tomato in greenhouse,including variety selec-tion,raising seedlings,field preparation,design of greenhouse size,field planting,field management,diseases and pests control,as well as harvest.

  6. The High Yield Cultivation Techniques of Blueberry in Suitable Habitat of Anhui%安徽蓝莓适生地蓝莓丰产栽培技术

    Institute of Scientific and Technical Information of China (English)

    樊基胜; 蒋光月; 陶龙

    2012-01-01

    在安徽蓝莓适生地多年蓝莓栽培和管理基础上总结了蓝莓丰产栽培技术,从建园、管理到采收方面作了详细的描述,并阐述了病虫鸟害的防治.%The high yield cultivation techniques of blueberry in suitable habitat of Anhui based on years of cultivation and management were summarized. Moreover, the construction of orchard, field management and harvesting were described in detail, the prevention and cure of pest and disease damage were expounded.

  7. High-yielding cultivation techniques of ginger in the mountainous area of southern Fujian%闽南山区生姜高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    叶涌清

    2011-01-01

    闽南山区具有发展生姜生产的环境条件和发展空间,该文介绍了生姜生产对环境条件的要求,生姜各生长时期的管理要点及其高产栽培技术。%The mountainous area of southern Fujian possesses the environmental conditions and potential developing space for ginger production.This paper described the environmental requirement,key management points in different growth period and high-yielding cultivation techniques of ginger.

  8. High Yield Culture Technique of Summer Ipomoea batatas in Binhai County%滨海县夏山芋高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    李庆体; 金叶红; 迟金和; 李晴; 刘永

    2011-01-01

    从品质选择、育苗、地块选择、施肥、移栽、除草、病虫害防治、收获与贮藏等方面总结夏山芋高产栽培技术,以提高滨海县的山芋生产水平。%The high yield culture techniques of summer Ipomoea batatas were summarized from several aspects,such as variety selection,seeding,field selection,fertilization,transplantation,weeding,disease and insect control,harvesting and storage,so as to improve the production level of Ipomoea batatas in Binhai County.

  9. Monte Carlo simulation of the neutron porosity logging using D-D neutron generator%D-D中子源孔隙度测井的蒙特卡洛模拟

    Institute of Scientific and Technical Information of China (English)

    严岩; 李炳营; 郑世平; 闫永宏; 杨尧; 姚泽恩; 刘炯

    2012-01-01

    The D-D neutron source model was developed according to the neutron energy spectrum and angular distribution of D-D reaction and the standard calibration well model was developed too. The D-D neutron transports in the well model were simulated using the MCNP code. The distributions of relative thermal neutron flux in axis and the relative porosity sensitivity for different source spacing were presented. The results show that the location of zero porosity sensitivity was about 17 cm, and the detector should be located at 25~60 cm space. According to the neutron energy spectrum and angular distribution data, the models of D-T and Am-Be neutron source were also developed. The near-to-far count ratio R and the porosity sensitivities S of the compensated neutron porosity logging were investigated respectively for D-T, D-D and Am-Be neutron sources using the MCNP code, and the results show that the D-D neutron source exhibited a higher sensitivity and higher neutron efficiency in contrast with D-T and Am-Be neutron sources.%根据D-D反应中子的能谱和角分布数据,建立了D-D中子源模型.根据标准刻度井数据,建立了井模型.采用MCNP程序模拟了D-D中子在井中的输运,给出了热中子相对通量沿轴线的分布和孔隙度探测灵敏度随源距的变化,结果显示对D-D中子源,孔隙度测量零灵敏约在17 cm附近,探测器的适宜布置区间为25~60 cm.根据D-T反应中子和Am-Be中子源的能谱及角分布数据,建立了其中子源模型,通过MCNP模拟,研究了补偿法孔隙度测井时近远探测器中的热中子计数比值R及测量灵敏度S随孔隙度的变化,并与D-D中子源的模拟结果进行了比较,结果显示D-D源有更高的测量灵敏度和更高的中子利用率.

  10. 2D and 3D T2-weighted MR sequences for the assessment of neurovascular bundle changes after nerve-sparing radical retropubic prostatectomy with erectile function correlation

    Energy Technology Data Exchange (ETDEWEB)

    Panebianco, Valeria; Osimani, Marcello; Lisi, Danilo; Passariello, Roberto [University of Rome ' ' Sapienza' ' -Policlinico Umberto I, Department of Radiological Sciences, Rome (Italy); Sciarra, Alessandro; Ciccariello, Mauro; Salciccia, Stefano; Gentile, Vincenzo; Di Silverio, Franco [University of Rome ' ' Sapienza' ' -Policlinico Umberto I, Department of Urology, Rome (Italy)

    2009-01-15

    The aim of this study was to assess the capability of a 3D isotropic MRI T2-weighted sequence (3D T2 ISO) in the depiction of changes of neurovascular bundles (NVBs) after bilateral nerve-sparing radical retropubic prostatectomy (RRP). Furthermore, our aim was also to introduce a new MRI classification score of the NVB alteration patterns using the International Index Erectile Function Five-Item (IIEF-5) score as standard of reference. Fifty-three consecutive patients were postoperatively submitted to two MR examinations, including both 2D TSE T2-weighted (2D T2) and 3D T2 ISO sequences. Image findings were scored using a relative five-point classification and correlated with the postoperative IIEF-5 score. Radiologists attributed 13.2% of patients to class 0, 11.3% to class I, 34% to class II, 24.5% to class III, and 16.9% to class IV. With 3D T2 ISO images, the same radiologists determined 43.3% class 0, 32% class I, 11.4% class II, 7.5% class III, and 5.7% class IV. In all cases, the correlation and regression analysis between the 3D T2 ISO and IIEF-5 score resulted in higher coefficients values. The 3D sequence correlated most closely with patients' grading of erectile function. (orig.)

  11. 2D and 3D T2-weighted MR sequences for the assessment of neurovascular bundle changes after nerve-sparing radical retropubic prostatectomy with erectile function correlation.

    Science.gov (United States)

    Panebianco, Valeria; Sciarra, Alessandro; Osimani, Marcello; Lisi, Danilo; Ciccariello, Mauro; Salciccia, Stefano; Gentile, Vincenzo; Di Silverio, Franco; Passariello, Roberto

    2009-01-01

    The aim of this study was to assess the capability of a 3D isotropic MRI T2-weighted sequence (3D T2 ISO) in the depiction of changes of neurovascular bundles (NVBs) after bilateral nerve-sparing radical retropubic prostatectomy (RRP). Furthermore, our aim was also to introduce a new MRI classification score of the NVB alteration patterns using the International Index Erectile Function Five-Item (IIEF-5) score as standard of reference. Fifty-three consecutive patients were postoperatively submitted to two MR examinations, including both 2D TSE T2-weighted (2D T2) and 3D T2 ISO sequences. Image findings were scored using a relative five-point classification and correlated with the postoperative IIEF-5 score. Radiologists attributed 13.2% of patients to class 0, 11.3% to class I, 34% to class II, 24.5% to class III, and 16.9% to class IV. With 3D T2 ISO images, the same radiologists determined 43.3% class 0, 32% class I, 11.4% class II, 7.5% class III, and 5.7% class IV. In all cases, the correlation and regression analysis between the 3D T2 ISO and IIEF-5 score resulted in higher coefficients values. The 3D sequence correlated most closely with patients' grading of erectile function.

  12. Neutron resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gunsing, F

    2005-06-15

    The present document has been written in order to obtain the diploma 'Habilitation a Diriger des Recherches'. Since this diploma is indispensable to supervise thesis students, I had the intention to write a document that can be useful for someone starting in the field of neutron resonance spectroscopy. Although the here described topics are already described elsewhere, and often in more detail, it seemed useful to have most of the relevant information in a single document. A general introduction places the topic of neutron-nucleus interaction in a nuclear physics context. The large variations of several orders of magnitude in neutron-induced reaction cross sections are explained in terms of nuclear level excitations. The random character of the resonances make nuclear model calculation predictions impossible. Then several fields in physics where neutron-induced reactions are important and to which I have contributed in some way or another, are mentioned in a first synthetic chapter. They concern topics like parity nonconservation in certain neutron resonances, stellar nucleosynthesis by neutron capture, and data for nuclear energy applications. The latter item is especially important for the transmutation of nuclear waste and for alternative fuel cycles. Nuclear data libraries are also briefly mentioned. A second chapter details the R-matrix theory. This formalism is the foundation of the description of the neutron-nucleus interaction and is present in all fields of neutron resonance spectroscopy. (author)

  13. Development of Neutron Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Hee; Lee, J. S.; Seong, B. S. (and others)

    2007-06-15

    Neutron spectrometers which are used in the basic researches such as physics, chemistry and materials science and applied in the industry were developed at the horizontal beam port of HANARO reactor. In addition, the development of core components for neutron scattering and the upgrade of existing facilities are also performed. The vertical neutron reflectometer was fabricated and installed at ST3 beam port. The performance test of the reflectometer was completed and the reflectometer was opened to users. The several core parts and options were added in the polarized neutron spectrometer. The horizontal neutron reflectometer from Brookhaven National Laboratory was moved to HANARO and installed, and the performance of the reflectometer was examined. The HIPD was developed and the performance test was completed. The base shielding for TAS was fabricated. The soller collimator, Cu mosaic monochromator, Si BPC monochromator and position sensitive detector were developed and applied in the neutron spectrometer as part of core component development activities. In addition, the sputtering machine for mirror device are fabricated and the neutron mirror is made using the sputtering machine. The FCD was upgraded and the performance of the FCD are improved over the factor of 10. The integration and upgrade of the neutron detection system were also performed.

  14. Neutron Star Matter

    CERN Document Server

    Wambach, Jochen

    2013-01-01

    In this presentation I discuss two aspects of the neutron-matter equation of state. One relates to the symmetry energy of nuclear matter and empirical constraints on its slope parameter at saturation density. The second deals with spatially inhomogeneous chiral phases of deconfined quark matter in the inner core of a neutron star.

  15. Neutron Multiplicity Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Frame, Katherine Chiyoko [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-28

    Neutron multiplicity measurements are widely used for nondestructive assay (NDA) of special nuclear material (SNM). When combined with isotopic composition information, neutron multiplicity analysis can be used to estimate the spontaneous fission rate and leakage multiplication of SNM. When combined with isotopic information, the total mass of fissile material can also be determined. This presentation provides an overview of this technique.

  16. Neutron capture therapies

    Energy Technology Data Exchange (ETDEWEB)

    Yanch, Jacquelyn C. (Cambridge, MA); Shefer, Ruth E. (Newton, MA); Klinkowstein, Robert E. (Winchester, MA)

    1999-01-01

    In one embodiment there is provided an application of the .sup.10 B(n,.alpha.).sup.7 Li nuclear reaction or other neutron capture reactions for the treatment of rheumatoid arthritis. This application, called Boron Neutron Capture Synovectomy (BNCS), requires substantially altered demands on neutron beam design than for instance treatment of deep seated tumors. Considerations for neutron beam design for the treatment of arthritic joints via BNCS are provided for, and comparisons with the design requirements for Boron Neutron Capture Therapy (BNCT) of tumors are made. In addition, exemplary moderator/reflector assemblies are provided which produce intense, high-quality neutron beams based on (p,n) accelerator-based reactions. In another embodiment there is provided the use of deuteron-based charged particle reactions to be used as sources for epithermal or thermal neutron beams for neutron capture therapies. Many d,n reactions (e.g. using deuterium, tritium or beryllium targets) are very prolific at relatively low deuteron energies.

  17. Neutron capture therapies

    Energy Technology Data Exchange (ETDEWEB)

    Yanch, J.C.; Shefer, R.E.; Klinkowstein, R.E.

    1999-11-02

    In one embodiment there is provided an application of the {sup 10}B(n,{alpha}){sup 7}Li nuclear reaction or other neutron capture reactions for the treatment of rheumatoid arthritis. This application, called Boron Neutron Capture Synovectomy (BNCS), requires substantially altered demands on neutron beam design than for instance treatment of deep seated tumors. Considerations for neutron beam design for the treatment of arthritic joints via BNCS are provided for, and comparisons with the design requirements for Boron Neutron Capture Therapy (BNCT) of tumors are made. In addition, exemplary moderator/reflector assemblies are provided which produce intense, high-quality neutron beams based on (p,n) accelerator-based reactions. In another embodiment there is provided the use of deuteron-based charged particle reactions to be used as sources for epithermal or thermal neutron beams for neutron capture therapies. Many d,n reactions (e.g. using deuterium, tritium or beryllium targets) are very prolific at relatively low deuteron energies.

  18. Neutron Stars and Pulsars

    CERN Document Server

    Becker, Werner

    2009-01-01

    Neutron stars are the most compact astronomical objects in the universe which are accessible by direct observation. Studying neutron stars means studying physics in regimes unattainable in any terrestrial laboratory. Understanding their observed complex phenomena requires a wide range of scientific disciplines, including the nuclear and condensed matter physics of very dense matter in neutron star interiors, plasma physics and quantum electrodynamics of magnetospheres, and the relativistic magneto-hydrodynamics of electron-positron pulsar winds interacting with some ambient medium. Not to mention the test bed neutron stars provide for general relativity theories, and their importance as potential sources of gravitational waves. It is this variety of disciplines which, among others, makes neutron star research so fascinating, not only for those who have been working in the field for many years but also for students and young scientists. The aim of this book is to serve as a reference work which not only review...

  19. Pocked surface neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas (Whitmore Lake, MI); Klann, Raymond (Bolingbrook, IL)

    2003-04-08

    The detection efficiency, or sensitivity, of a neutron detector material such as of Si, SiC, amorphous Si, GaAs, or diamond is substantially increased by forming one or more cavities, or holes, in its surface. A neutron reactive material such as of elemental, or any compound of, .sup.10 B, .sup.6 Li, .sup.6 LiF, U, or Gd is deposited on the surface of the detector material so as to be disposed within the cavities therein. The portions of the neutron reactive material extending into the detector material substantially increase the probability of an energetic neutron reaction product in the form of a charged particle being directed into and detected by the neutron detector material.

  20. Neutron stars - General review

    Science.gov (United States)

    Cameron, A. G. W.; Canuto, V.

    1974-01-01

    A review is presented of those properties of neutron stars upon which there is general agreement and of those areas which currently remain in doubt. Developments in theoretical physics of neutron star interiors are summarized with particular attention devoted to hyperon interactions and the structure of interior layers. Determination of energy states and the composition of matter is described for successive layers, beginning with the surface and proceeding through the central region into the core. Problems encountered in determining the behavior of matter in the ultra-high density regime are discussed, and the effects of the magnetic field of a neutron star are evaluated along with the behavior of atomic structures in the field. The evolution of a neutron star is outlined with discussion centering on carbon detonation, cooling, vibrational damping, rotation, and pulsar glitches. The role of neutron stars in cosmic-ray propagation is considered.

  1. Demonstration and Radiation Extension mode of Agricultural Technology——A Case of the Science and Technology Project of High Yield in Hebei Province

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Firstly,relying on the science and technology project of high yield in Hebei Province,connotation of agricultural technology demonstration and extension mode and the high yield grain project in Hebei Province is introduced.Extension mode of agricultural technology demonstration and radiation is constructed.Agricultural technology demonstration and radiation mode includes the radiation center,primary irradiation and secondary irradiation.Secondly,management system and operational mechanism of agricultural technology demonstration and radiation mode are discussed,mainly expressed in establishing leading group in each demonstration county(city),carrying out leader contract responsibility system,establishing expert advisor steering group and setting up core experts group for subject,establishing technical experts group for subject,setting up leading group in the radiation area,carrying out chief expert responsibility system and technician matrix responsibility system,establishing the operating mechanism of "open,flow,competition and collaboration" with "test area-expert two-way selection" as the core content.Finally,countermeasures to improve the agricultural technology demonstration and radiation mode is put forward,such as establishing the rural technology demonstration base,strengthening cooperation with enterprises,and adopting flexible technical training,so as to promote the spread of agricultural high-tech,to increase the contribution rate of agricultural technology,and to offer ideas for agricultural technology extension model at the new era.

  2. Photochemical properties in flag leaves of a super-high-yielding hybrid rice and a traditional hybrid rice (Oryza sativa L.) probed by chlorophyll a fluorescence transient.

    Science.gov (United States)

    Zhang, Meiping; Shan, YongJie; Kochian, Leon; Strasser, Reto J; Chen, GuoXiang

    2015-12-01

    Chlorophyll a fluorescence of flag leaves in a super-high-yielding hybrid rice (Oryza sativa L.) LYPJ, and a traditional hybrid rice SY63 cultivar with lower grain yield, which were grown in the field, were investigated from emergence through senescence of flag leaves. As the flag leaf matured, there was an increasing trend in photosynthetic parameters such as quantum efficiency of primary photochemistry ([Formula: see text] Po) and efficiency of electron transport from PS II to PS I (Ψ Eo). The overall photosynthetic performance index (PIABS) was significantly higher in the high-yielding LYPJ compared to SY63 during the entire reproductive stage of the plant, the same to MDA content. However, [Formula: see text] Po(=F V/F M), an indicator of the primary photochemistry of the flag leaf, did not display significant changes with leaf age and was not significantly different between the two cultivars, suggesting that PIABS is a more sensitive parameter than [Formula: see text] Po (=F V/F M) during leaf age for distinguishing between cultivars differing in yield.

  3. High Yield Cultivation Experimental Study of Olive in Lijiang%丽江市油橄榄丰产栽培试验研究

    Institute of Scientific and Technical Information of China (English)

    子桂才

    2013-01-01

    在丽江市玉龙县大具乡进行油橄榄丰产栽培试验研究.文中阐述油橄榄的栽植、土壤管理、水肥管理、整形修剪、病虫害防治等技术方法.试验结果表明,佛奥、豆果、皮瓜尔3个参试品种的扦插苗(2 a生)第三年开始结果,参试品种的单株产量、公顷产量与对照组相比均有较大提高,达到了丰产的效果.%High yield experimental study of olive was carried out in Daju Town,Yulong County of Lijiang.Cultivation,soil management,water and fertilizer management,pruning,pest control and other technical methods were elaborated.The experimental results showed that cutting seedling (2 year old) of the three varieties of Olive (Frantoio,Arbeqina,Picual) started to fruit in the 3rd year.Yield per plant and yield per hectare of testing varieties have been greatly improved compared with the control group and achieve high yield effect.

  4. SINGLE CRYSTAL NEUTRON DIFFRACTION.

    Energy Technology Data Exchange (ETDEWEB)

    KOETZLE,T.F.

    2001-03-13

    Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for information on magnetic scattering of neutrons see Unit 14.3. Instruments for single-crystal diffraction (single-crystal diffractometers or SCDs) are generally available at the major neutron scattering center facilities. Beam time on many of these instruments is available through a proposal mechanism. A listing of neutron SCD instruments and their corresponding facility contacts is included in an appendix accompanying this unit.

  5. Optical polarizing neutron devices designed for pulsed neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, M.; Kurahashi, K.; Endoh, Y. [Tohoku Univ, Sendai (Japan); Itoh, S. [National Lab. for High Energy Physics, Tsukuba (Japan)

    1997-09-01

    We have designed two polarizing neutron devices for pulsed cold neutrons. The devices have been tested at the pulsed neutron source at the Booster Synchrotron Utilization Facility of the National Laboratory for High Energy Physics. These two devices proved to have a practical use for experiments to investigate condensed matter physics using pulsed cold polarized neutrons.

  6. Reactor applications of the compact fusion advanced Rankine (CFAR) cycle for a D-T tokamak fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, H.A.; Logan, B.G.; Campbell, R.B.

    1988-03-01

    We have made a preliminary design of a D-T fusion reactor blanket and MHD power conversion system based on the CFAR concept, and found that the performance and costs for the reference cycle are very attractive. While much remains to be done, the potential advantage of liquid metal Rankine cycles for fusion applications are much clearer now. These include low pressures and mass flow rates, a nearly isothermal module shell which minimizes problems of thermal distortion and stresses, and an insensitivity to pressure losses in the blanket so that the two-phase MHD pressure drops in the boilling part of the blanket and the ordinary vapor pressure drops in the pebble-bed superheating zones are acceptable (the direct result of pumping a liquid rather than having to compress a gas). There are no moving parts in the high-temperature MHD power generators, no steam bottoming plant is required, only small vapor precoolers and condensers are needed because of the high heat rejection trmperatures, and only a relatively small natural-draft heat exhanger is required to reject the heat to the atmosphere. The net result is a very compact fusion reactor and power conversion system which fit entirely inside an 18 meter radius reactor vault. Although we have not yet performed a detailed cost analysis, preliminary cost estimates indicate low capital costs and a very attractive cost of electricity. 11 refs., 5 figs., 2 tabs.

  7. Analysis of poly(A + RNA distribution during maize somatic embryogenesis using digoxigenated oligo-dT probes

    Directory of Open Access Journals (Sweden)

    R. Bimal

    2014-01-01

    Full Text Available The pattern of total transcription activity in terms of steady state levels of poly(A+ containing mRNA during callus initiation and somatic embryogenesis in a high (A188 and a low (A632 embryogenic line of maize was analyzed using digoxigenin labelled oligo-dT probes. A gradual increase and a preferential accumulation of label was observed in both lines, differing temporally up to 4 days in culture. In the A188 line of maize the callus gave rise to somatic embryos. The globular embryos showed less label than the callus; this labelling was mostly present in the basal part of the embryos. At a later stage upper embryogenic and lower non-embryogenic layers were observed in the A188 callus, showing conspicuous differences in the amount of label. In the late globular stage the poly(A+ RNA signals were seen all over the embryo but at the junction of the suspensor and the callus tissue no label was observed.

  8. Fail-safe neutron shutter used for thermal neutron radiography

    Energy Technology Data Exchange (ETDEWEB)

    Sachs, R.D.; Morris, R.A.

    1976-11-01

    A fail-safe, reliable, easy-to-use neutron shutter was designed, built, and put into operation at the Omega West Reactor, Los Alamos Scientific Laboratory. The neutron shutter will be used primarily to perform thermal neutron radiography, but is also available for a highly collimated source of thermal neutrons (neutron flux = 3.876 x 10/sup 6/ (neutrons)/(cm/sup 2/.s)). Neutron collimator sizes of either 10.16 by 10.16 cm or 10.16 by 30.48 cm are available.

  9. The New Sorgentina Fusion Source-NSFS: 14 MeV neutrons for fusion and beyond

    Science.gov (United States)

    Pietropaolo, A.; Console Camprini, P.; Agostini, P.; Amendola, R.; Angelone, M.; Bernardi, D.; Bruni, F.; Capogni, M.; Colognesi, D.; Faccini, R.; Filabozzi, A.; Flammini, D.; Fiori, F.; Frisoni, M.; Grazzi, F.; Pillon, M.; Pizzuto, A.; Quintieri, L.; Sacchetti, F.; Valente, P.

    2016-09-01

    The importance of the design for the realization of an intense 14 MeV neutron facility devoted to test and validate materials suitable for harsh neutron environments, such as a fusion reactor, is well established. The “New Sorgentina” Fusion Source (NSFS) is a project that proposes an intense D-T 14 MeV neutron source achievable with T and D ion beams impinging on 2 m radius rotating targets. NSFS may produce about 1015 n/s at the target and has to be intended as an European facility that maybe realized in a few years, once provided a preliminary technological program devoted to the operation of the ion source in continuous mode, target heat loading/removal, target and tritium handling, inventor as well as site licensing. In this contribution, the main characteristics of NSFS project will be presented and its possible use as a multipurpose facility outlined.

  10. The value of 3D T1-weighted gradient-echo MR imaging for evaluation of the appendix during pregnancy: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Kyung Mi; Kim, Seong Hyun; Choi, Dongil; Lee, Soon Jin; Rhim, Hyunchul; Park, Min Jung (Depts. of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of)), email: kshyun@skku.edu

    2011-10-15

    Background The use of oral contrast has been essential for the identification of a normal appendix on MR imaging during pregnancy. However, stool could be used as a positive oral contrast as it is characterized by a relatively high signal on T1-weighted imaging, and 3D T1-weighted gradient-echo (T1W-GRE) MR imaging has been used to evaluate 3 mm diameter intestines in fetuses. Purpose To evaluate the added value of 3D T1W-GRE MR imaging in combination with T2-weighted imaging (T2WI) compared to T2WI alone for evaluating the appendix during pregnancy. Material and Methods Eighteen consecutive pregnant patients who were clinically suspected of having acute appendicitis underwent appendix MR imaging which included T2WI with or without spectral presaturation attenuated inversion-recovery (SPAIR) fat suppression, and 3D T1W-GRE with SPAIR fat suppression. Two radiologists reviewed the two image sets (the T2WI set and the combined set of T2WI and 3D T1W-GRE images). Pathologic and clinical results served as the reference standard. The differences in the degree of visibility of the appendix and confidence scale for diagnosing acute appendicitis between two image sets were compared by using the paired Wilcoxon signed rank test. Results For both reviewers, the degree of visibility of the appendix using the combined T2WI and 3D T1W-GRE images was significantly higher than using T2WI alone (P < 0.01), and the confidence levels for acute appendicitis using combined T2WI and 3D T1W-GRE images were significantly different from those using T2WI alone (P < 0.01). In the 13 patients with a normal appendix, both reviewers showed improved confidence levels for appendicitis using combined T2WI and 3D T1W-GRE images than T2WI alone. Conclusion Adding 3D T1W-GRE images to T2WI is helpful for identification of the appendix, as compared to T2WI alone in pregnant women without ingestion of oral contrast material. This may improve diagnostic confidence for acute appendicitis in pregnant

  11. Precision Measurement of 56Fe(n,n γ) Cross Sections Using 14.1 MeV Neutrons

    Science.gov (United States)

    Wang, Haoyu; Koltick, David

    2016-03-01

    Integral production cross sections for 846.8 keV and 1238.3 keV prompt gamma rays from 14.1 MeV neutrons interactions on 56Fe are reported. The experimental technique takes advantage of the 1.5 nanosecond coincidence timing resolution between the neutron production time and the gamma ray detection time to reject noise, together with the large 30% solid angle gamma ray coverage. The scattering angle coverage with respect to the neutron beam direction extends from 60 degrees to 120 degrees. The neutron flux is measured using the detected associated alpha-particle from the D-T fusion reaction produced using an associated particle neutron generator. Present cross section measurements using other techniques with limited timing resolution and solid angle coverage are in agreement at neutron energies lower than 6 MeV. At higher neutron energies reported results can disagree by more than 20%. The more accurate technique used in these measurements can distinguish between the differences in the present reported results at higher neutron energies. The author would like to thank TechSource, Inc. and Advanced Physics Technologies, LLC. for their support in this work.

  12. Precision Cross Sections Measurement of 56Fe(n,n γ) at 14.1 MeV using Associated Particle Neutron Elemental Imaging Technique

    Science.gov (United States)

    Wang, Haoyu; Koltick, David

    2017-01-01

    Integral production cross sections for 846.8 keV and 1238.3 keV prompt gamma rays from 14.1 MeV neutrons interactions on 56Fe and are reported, using Associated Particle Neutron Elemental Imaging technique. The experimental technique involves: (1) The development of a VME standard high speed DAQ system and a MATLAB parallel cluster for offline signal analysis with full control of data flow; (2) The advantage of the <1.5 ns coincidence timing resolution between the neutron production and the gamma ray detection to reject noise; (3) A large 30% solid angle gamma ray coverage by an array of NaI(Tl) detectors. The neutron flux is measured through detecting the associated alpha-particle from the D-T fusion reaction in the neutron generator. Present cross section measurements using other techniques with limited timing resolution and solid angle coverage are in agreement at neutron energies lower than 6 MeV. At higher neutron energies reported results can disagree by more than 20%. This more accurate technique presented can distinguish between the differences in the reported results based on pulse-mode neutron source and neutron time-of-flight techniques, at higher neutron energies.

  13. Neutron scattering in liquids

    Energy Technology Data Exchange (ETDEWEB)

    Barocchi, F. [Florence Univ. (Italy). Ist. di Fisica

    1996-12-31

    Together with X-rays, thermal neutrons are the ideal probe to study the microscopic structure of condensed matter, however the precision attainable usually with neutrons for the measurement of atomic position correlation functions in liquids is, at least, one order of magnitude better than for X-rays. In order to measure properly the microscopic dynamics a wide range of momentum transfer with corresponding energy transfer must be available in the range of liquid state excitations. This again is only attainable, with good resolution, with neutrons. (author) 7 figs., 3 refs.

  14. Neutrons in soft matter

    CERN Document Server

    Imae, Toyoko; Furusaka, Michihiro; Torikai, Naoya

    2011-01-01

    Neutron and synchrotron facilities, which are beyond the scale of the laboratory, and supported on a national level in countries throughout the world.  These tools for probing micro- and nano-structure research and on fast dynamics research of atomic location in materials have been key in the development of new polymer-based materials. Different from several existing professional books on neutron science, this book focuses on theory, instrumentation, an applications. The book is divided into five parts: Part 1 describes the underlying theory of neutron scattering. Part 2 desc

  15. Technology of High Yield Cultivation of Banana in Hainan%海南香蕉高产栽培技术要点

    Institute of Scientific and Technical Information of China (English)

    朱杰

    2015-01-01

    The cultivation and management of banana was an important factor to realize higher quality and higher yield, improve the economic benefit and promote the development of banana industry. In this paper, the author mainly introduced the high yield cultivation techniques, pest control methods and technical problems in production, in order to provide technical guidance for banana producers.%做好香蕉的栽培、管理是实现香蕉优质高产、提高经济效益、促进香蕉产业地不断发展的重要因素。本文主要介绍了香蕉的高产栽培技术、病虫害防治方法以及生产中应注意的技术问题,以期为香蕉生产者提供技术指导。

  16. 蕉芋优质高产栽培技术%High quality and high-yielding cultivation techniques of edible canna(Canna edulis)

    Institute of Scientific and Technical Information of China (English)

    刘恒

    2012-01-01

    蕉芋的市场发展前景广阔。该文从品种选择、土壤选择、耕翻整地、幼苗繁殖、适时定植、田间管理、水分管理、病虫害防治、采收与加工等方面介绍蕉芋的优质高产栽培技术。%Edible canna has good market potential.This paper introduced high quality and high-yielding cultivation techniques of edible canna,including cultivar selection,soil selection,ploughing and soil preparation,seedling propagation,planting in suitable time,field management,water management,control of diseases and pests,harvest and processing.

  17. Se-Enriched Hot Pepper Cultivation for High Yield and Quality%富硒番茄优质高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    邓正春; 吴平安; 杜登科; 汤小明; 熊伟

    2011-01-01

    This paper discusses the Se-enriched tomato cultivation for high yield and quality in terms of production site condition, variety selection, seed treatment, growing seedling, timely transplanting, field management, pest control, scientific application of selenium, and timely harvesting.%系统介绍了富硒番茄优质高产栽培技术。指出在富硒番茄生产过程中应注意立地条件、品种选择、种子处理、培育壮苗、及时移栽、田间培管、病虫防治、科学施硒及适时采收等栽培技术要点。

  18. Cellulose acetate-directed growth of bamboo-raft-like single-crystalline selenium superstructures: high-yield synthesis, characterization, and formation mechanism.

    Science.gov (United States)

    Song, Ji-Ming; Zhan, Yong-Jie; Xu, An-Wu; Yu, Shu-Hong

    2007-06-19

    High-yield synthesis of bamboo-raft-like single-crystalline selenium superstructures has been realized for the first time via a facile solvothermal approach by reducing SeO2 with ethylene alcohol in the presence of cellulose acetate. The formation of a raftlike superstructure with various forms is strongly dependent on the temperature, amount of cellulose acetate, reaction time, and even preheating treatment. The suitable amount of cellulose acetate is essential for the formation of elegant and uniform raft Se. The morphology, microstructure, optical properties, and chemical compositions of bamboo-raft-like selenium were characterized using various techniques (X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy (TEM), high-resolution (HR) TEM, X-ray photoelectron spectroscopy, UV-vis spectroscopy, FTIR spectroscopy, and Raman spectroscopy). A possible growth mechanism has been proposed. Such special superstructures could provide a useful precursor for potential applications.

  19. 豫东平原夏玉米高产栽培技术%High Yield Cultivation Techniques of Summer Maize in the Plain Area of Eastern Henan

    Institute of Scientific and Technical Information of China (English)

    张永阁

    2015-01-01

    High yield cultivation techniques of summer maize in the plain area of Eastern Henan were summarized from species selection,sowing,thinning and spacing,fertilizer and water management,control of pest and disease and grass,harvest late at the appropriate time etc,so as to promote the cultivation of summer maize at the local.%从品种选择、播种、间苗定苗、肥水管理、病虫草害防治、适期晚收等方面总结了豫东平原夏玉米高产栽培技术,以促进当地夏玉米的高产栽培。

  20. Discussion on High Yield Cultivation Techniques of Summer Corn without Tillage%夏玉米免耕高产高效栽培技术探讨

    Institute of Scientific and Technical Information of China (English)

    王超; 王为联; 余福州

    2014-01-01

    从介绍夏玉米免耕机械直播的优点出发,阐述了夏玉米免耕高产高效栽培技术,包括麦茬处理、选用品种及种子处理、播种及田间管理等方面,为夏玉米生产提供了技术参考。%Starting from introducing the advantages of machinery direct seeding summer corn without tillage, the high yield cultivation techniques of summer corn without tillage were elaborated from the following aspects, including stubble treatment, the choice of varieties and seed treatment, planting and field management, etc. The results provided technical references for summer corn production.

  1. High-yield Cultivation Techniques of Green Corn in Weishan County%巍山县青玉米高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    谢增纲

    2014-01-01

    介绍巍山县青玉米的高产栽培技术,包括选种及种子处理、选地与整地、播种覆膜、田间管理及病虫草害防治等,以期为该县青玉米的发展提供参考。%High-yield cultivation techniques of green corn in Weishan County were introduced,including seed selection and treatment,selection and preparation of ground,seeding mulching,field management,pest and disease and grass control etc.,so as to provide reference for the development of green corn in Weishan County.

  2. 东塘水蜜桃高产优质栽培技术%High yield and quality cultivation techniques for honey peach in Dongtang

    Institute of Scientific and Technical Information of China (English)

    陈华勤

    2015-01-01

    Biological characteristics of Dongtang honey peach were observed,and the high yield and quality cultivation tech-nique was summarized,which included garden construction planning,scientific cultivation,reasonable pruning,establishing healthy tree crown,scientific fertilization,improving quality,and pests and diseases control.%通过对东塘水蜜桃生物学性状进行观察,总结其高产优质栽培技术:规划建园,科学种植;合理整枝修剪,培养良好树冠;科学施肥,提高品质;科学防治病虫害。

  3. High-yielding Cultivation Technology for Middle Rice- succeeded Black Fungus%中稻—袋料黑木耳高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    吴火金

    2015-01-01

    为充分利用土地闲置田的空间,种植一季水稻后,再放置黑木耳,既发挥土地资源,又提高经济效益,从而增加农民收入.主要阐述了浦城县种植一季中稻后袋料黑木耳的主要高产栽培技术,病虫发生与防治.%In this paper, to make full use of idle land field space, after the rice planting season, again to place black fungus, both play land resources, and improve the economic benefit, increasing farmers' income. In this paper, we mainly expounds middle rice planting season succeeded after black fungus main high-yield culti-vation techniques, the occurrence and prevention of diseases and pests.

  4. Recyclable transmission line (RTL) and linear transformer driver (LTD) development for Z-pinch inertial fusion energy (Z-IFE) and high yield.

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, Robin Arthur; Kingsep, Alexander S. (Kurchatov Institute, Moscow, Russia); Smith, David Lewis; Olson, Craig Lee; Ottinger, Paul F. (Naval Research Laboratory, Washington, DC); Schumer, Joseph Wade (Naval Research Laboratory, Washington, DC); Welch, Dale Robert (Voss Scientific, Albuquerque, NM); Kim, Alexander (High Currents Institute, Tomsk, Russia); Kulcinski, Gerald L. (University of Wisconsin, Madison, WI); Kammer, Daniel C. (University of Wisconsin, Madison, WI); Rose, David Vincent (Voss Scientific, Albuquerque, NM); Nedoseev, Sergei L. (Kurchatov Institute, Moscow, Russia); Pointon, Timothy David; Smirnov, Valentin P. (Kurchatov Institute, Moscow, Russia); Turgeon, Matthew C.; Kalinin, Yuri G. (Kurchatov Institute, Moscow, Russia); Bruner, Nichelle " Nicki" (Voss Scientific, Albuquerque, NM); Barkey, Mark E. (University of Alabama, Tuscaloosa, AL); Guthrie, Michael (University of Wisconsin, Madison, WI); Thoma, Carsten (Voss Scientific, Albuquerque, NM); Genoni, Tom C. (Voss Scientific, Albuquerque, NM); Langston, William L.; Fowler, William E.; Mazarakis, Michael Gerrassimos

    2007-01-01

    Z-Pinch Inertial Fusion Energy (Z-IFE) complements and extends the single-shot z-pinch fusion program on Z to a repetitive, high-yield, power plant scenario that can be used for the production of electricity, transmutation of nuclear waste, and hydrogen production, all with no CO{sub 2} production and no long-lived radioactive nuclear waste. The Z-IFE concept uses a Linear Transformer Driver (LTD) accelerator, and a Recyclable Transmission Line (RTL) to connect the LTD driver to a high-yield fusion target inside a thick-liquid-wall power plant chamber. Results of RTL and LTD research are reported here, that include: (1) The key physics issues for RTLs involve the power flow at the high linear current densities that occur near the target (up to 5 MA/cm). These issues include surface heating, melting, ablation, plasma formation, electron flow, magnetic insulation, conductivity changes, magnetic field diffusion changes, possible ion flow, and RTL mass motion. These issues are studied theoretically, computationally (with the ALEGRA and LSP codes), and will work at 5 MA/cm or higher, with anode-cathode gaps as small as 2 mm. (2) An RTL misalignment sensitivity study has been performed using a 3D circuit model. Results show very small load current variations for significant RTL misalignments. (3) The key structural issues for RTLs involve optimizing the RTL strength (varying shape, ribs, etc.) while minimizing the RTL mass. Optimization studies show RTL mass reductions by factors of three or more. (4) Fabrication and pressure testing of Z-PoP (Proof-of-Principle) size RTLs are successfully reported here. (5) Modeling of the effect of initial RTL imperfections on the buckling pressure has been performed. Results show that the curved RTL offers a much greater buckling pressure as well as less sensitivity to imperfections than three other RTL designs. (6) Repetitive operation of a 0.5 MA, 100 kV, 100 ns, LTD cavity with gas purging between shots and automated operation is

  5. Combining metabolic engineering and biocompatible chemistry for high-yield production of homo-diacetyl and homo-(S,S)-2,3-butanediol

    DEFF Research Database (Denmark)

    Liu, Jianming; Chan, Siu Hung Joshua; Brock-Nannestad, Theis;

    2016-01-01

    Biocompatible chemistry is gaining increasing attention because of its potential within biotechnology for expanding the repertoire of biological transformations carried out by enzymes. Here we demonstrate how biocompatible chemistry can be used for synthesizing valuable compounds as well as for l...... of 82%. The diacetyl and S-BDO production rates and yields obtained are the highest ever reported, demonstrating the promising combination of metabolic engineering and biocompatible chemistry as well as the great potential of L. lactis as a new production platform.......M or 8.2g/L) and high yield (87% of the theoretical maximum). Subsequently, the pathway was extended to (S,S)-2,3-butanediol (S-BDO) through efficiently linking two metabolic pathways via chemical catalysis. This resulted in efficient homo-S-BDO production with a titer of 74mM (6.7g/L) S-BDO and a yield...

  6. High Yield Cultivation Techniques of Cherry Tomato in Guangxi%广西樱桃番茄高产栽培技术探讨

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Cherry tomatoes were the leading industry in Tianyang of Guangxi. The high yield cultivation techniques were summarized from the following aspects , including varieties selection, breeding strong seedlings, intensive cultivation and strengthening base fertilizers, timely planting, scientific field management, making frames for the climbing, pollination, control of diseases and pests, and so on. The results provided technical information for production of cherry tomatoes.%樱桃番茄是广西田阳的主导产业。从品种选择、培育壮苗、精耕细作、重施基肥、定植、田间水肥管理、及时插杆整枝、点花授粉及病虫害防治等几个方面总结了樱桃番茄超高产栽培技术,为生产提供了技术参考。

  7. Pollution-free and high-yielding cultivation techniques of edamame bean%毛豆高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    刘必胜

    2012-01-01

    This paper introduced characteristics and environmental requirement of edamame bean.Some high-yielding cultivation techniques,including field selection,soil preparation,seed pretreatment,scientific topdressing,hilling in the intertillage operation,irrigation and drainage and control of diseases and pests were summarized.%介绍毛豆品种特征特性及毛豆生长对环境条件的要求,从地块选择、整地、种子处理、播种、科学追肥、中耕培土、灌溉排水、病虫害防治等方面总结了毛豆的高产栽培技术。

  8. An improved procedure for the preparation of Ru(bpz3(PF62 via a high-yielding synthesis of 2,2’-bipyrazine

    Directory of Open Access Journals (Sweden)

    Danielle M. Schultz

    2015-01-01

    Full Text Available There has been a recent surge of interest in the use of transition metal polypyridyl complexes as visible light-absorbing photocatalysts for synthetic applications. Among the most attractive features of this approach is the availability of many known complexes with well-characterized photophysical and electrochemical properties. In particular, Ru(bpz32+ is a powerful photooxidant that has proven to be uniquely suited for oxidatively induced photoredox transformations. We present here a straightforward and high-yielding route to Ru(bpz3(PF62 that features an improved Pd-catalyzed synthesis of the 2,2’-bipyrazine ligand that is amenable to gram-scale preparations.

  9. High Yield Cultural Technique of Long Yam in Yichang Area%宜昌地区长山药高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    王鹏程; 宋晓东; 常红青; 许安频; 陈兵

    2012-01-01

    长山药(Dioscorea batatas Decne.)是药食兼用植物,近几年受到越来越多消费者的青睐.通过几年的长山药栽培实践,总结出了一套适宜在宜昌地区推广应用的长山药优质高产栽培技术.%Long yam(Dioscorea batatas Decne.) is a medicinal and edible plant. Because of its health value, it has gotten more and more consumer's interests in recent years. A set of high quality and high yield cultivation technology suitable for popularization in Yichang area were summarized through years of yam cultivation practice.

  10. Non-polluted & high-yield cultivation technology of cowpea in small shed%小拱棚无公害豇豆高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    何锐宗

    2009-01-01

    To plant cowpea in plastic-film small shed can increase the vegetable's quality and yield, advance the marketing time and gain better beneficial results. This paper will introduce the non-polluted & high-yield cultivation technology of red cowpea in small shed.%利用塑料薄膜小拱棚进行无公害豇豆栽培,可以提高豇豆质量和产量,提早上市时间,获得较好经济效益.本文介绍利用塑料薄膜小拱棚生产无公害豇豆的高产高效栽培技术.

  11. High-Yield Method for Isolation and Culture of Endothelial Cells from Rat Coronary Blood Vessels Suitable for Analysis of Intracellular Calcium and Nitric Oxide Biosynthetic Pathways

    Directory of Open Access Journals (Sweden)

    Nistri Silvia

    2002-01-01

    Full Text Available We describe here a method for isolating endothelial cells from rat heart blood vessels by means of coronary microperfusion with collagenase. This methods makes it possible to obtain high amounts of endothelial cells in culture which retain the functional properties of their in vivo counterparts, including the ability to uptake fluorescently-labeled acetylated low-density lipoproteins and to respond to vasoactive agents by modulating intracellular calcium and by upregulating intrinsic nitric oxide generation. The main advantages of our technique are: (i good reproducibility, (ii accurate sterility that can be maintained throughout the isolation procedure and (iii high yield of pure endothelial cells, mainly due to microperfusion and temperature-controlled incubation with collagenase which allow an optimal distribution of this enzyme within the coronary vascular bed.

  12. Study of proximal femoral bone perfusion with 3D T1 dynamic contrast-enhanced MRI: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Budzik, Jean-Francois [Groupe Hospitalier de l' Institut Catholique de Lille / Faculte Libre de Medecine, Service d' Imagerie Medicale, Lille (France); Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHRU de Lille, Service de Radiologie et Imagerie Musculosquelettique, Lille (France); Universite Catholique de Lille, Lille (France); Universite Nord de France, Lille (France); EA 4490 PMOI (Physiopathologie des Maladies Osseuses Inflammatoires) IFR 114 PRES Universite Lille Nord de France, Lille (France); Lefebvre, Guillaume; El Rafei, Mazen [Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHRU de Lille, Service de Radiologie et Imagerie Musculosquelettique, Lille (France); Universite Nord de France, Lille (France); CHU Lille, Lille (France); Forzy, Gerard [Universite Catholique de Lille, Lille (France); Universite Nord de France, Lille (France); Groupe Hospitalier de l' Institut Catholique de Lille, Laboratoire de Biologie, Departement de Biostatistiques, Lille (France); Chechin, David [Philips Medical Systems, Suresnes (France); Cotten, Anne [Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHRU de Lille, Service de Radiologie et Imagerie Musculosquelettique, Lille (France); Universite Nord de France, Lille (France); EA 4490 PMOI (Physiopathologie des Maladies Osseuses Inflammatoires) IFR 114 PRES Universite Lille Nord de France, Lille (France); CHU Lille, Lille (France)

    2014-12-15

    The objective of this study was to compare measurements of semi-quantitative and pharmacokinetic parameters in areas of red (RBM) and yellow bone marrow (YBM) of the hip, using an in-house high-resolution DCE T1 sequence, and to assess intra- and inter-observer reproducibility of these measurements. The right hips of 21 adult patients under 50 years of age were studied. Spatial resolution was 1.8 x 1.8 x 1.8 mm{sup 3}, and temporal resolution was 13.5 seconds. Two musculoskeletal radiologists independently processed DCE images and measured semi-quantitative and pharmacokinetic parameters in areas of YBM and RBM. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were calculated. Intra- and inter-observer reproducibility was assessed. Area under the curve (AUC) and initial slope (IS) were significantly greater for RBM than for YBM (p < 0.05). K{sup trans} and k{sub ep} were also significantly greater for RBM (p < 0.05). There was no significant difference in time to peak between the regions (p < 0.05). SNR, CNR, and intra- and inter-observer reproducibility were all good. DCE study of the whole hip is feasible with high spatial resolution using a 3D T1 sequence. Measures were possible even in low vascularized areas of the femoral head. K{sup trans}, k{sub ep}, AUC, and IS values were significantly different between red and yellow marrow, whereas TTP values were not. (orig.)

  13. Using an Active-Optical Sensor to Develop an Optimal NDVI Dynamic Model for High-Yield Rice Production (Yangtze, China).

    Science.gov (United States)

    Liu, Xiaojun; Ferguson, Richard B; Zheng, Hengbiao; Cao, Qiang; Tian, Yongchao; Cao, Weixing; Zhu, Yan

    2017-03-24

    The successful development of an optimal canopy vegetation index dynamic model for obtaining higher yield can offer a technical approach for real-time and nondestructive diagnosis of rice (Oryza sativa L) growth and nitrogen (N) nutrition status. In this study, multiple rice cultivars and N treatments of experimental plots were carried out to obtain: normalized difference vegetation index (NDVI), leaf area index (LAI), above-ground dry matter (DM), and grain yield (GY) data. The quantitative relationships between NDVI and these growth indices (e.g., LAI, DM and GY) were analyzed, showing positive correlations. Using the normalized modeling method, an appropriate NDVI simulation model of rice was established based on the normalized NDVI (RNDVI) and relative accumulative growing degree days (RAGDD). The NDVI dynamic model for high-yield production in rice can be expressed by a double logistic model: RNDVI = ( 1 + e - 15.2829 × ( R A G D D i - 0.1944 ) ) - 1 - ( 1 + e - 11.6517 × ( R A G D D i - 1.0267 ) ) - 1 (R2 = 0.8577**), which can be used to accurately predict canopy NDVI dynamic changes during the entire growth period. Considering variation among rice cultivars, we constructed two relative NDVI (RNDVI) dynamic models for Japonica and Indica rice types, with R2 reaching 0.8764** and 0.8874**, respectively. Furthermore, independent experimental data were used to validate the RNDVI dynamic models. The results showed that during the entire growth period, the accuracy (k), precision (R2), and standard deviation of RNDVI dynamic models for the Japonica and Indica cultivars were 0.9991, 1.0170; 0.9084**, 0.8030**; and 0.0232, 0.0170, respectively. These results indicated that RNDVI dynamic models could accurately reflect crop growth and predict dynamic changes in high-yield crop populations, providing a rapid approach for monitoring rice growth status.

  14. Negative energy balance and hepatic gene expression patterns in high-yielding dairy cows during the early postpartum period: a global approach.

    Science.gov (United States)

    McCarthy, S D; Waters, S M; Kenny, D A; Diskin, M G; Fitzpatrick, R; Patton, J; Wathes, D C; Morris, D G

    2010-11-15

    In high-yielding dairy cows the liver undergoes extensive physiological and biochemical changes during the early postpartum period in an effort to re-establish metabolic homeostasis and to counteract the adverse effects of negative energy balance (NEB). These adaptations are likely to be mediated by significant alterations in hepatic gene expression. To gain new insights into these events an energy balance model was created using differential feeding and milking regimes to produce two groups of cows with either a mild (MNEB) or severe NEB (SNEB) status. Cows were slaughtered and liver tissues collected on days 6-7 of the first follicular wave postpartum. Using an Affymetrix 23k oligonucleotide bovine array to determine global gene expression in hepatic tissue of these cows, we found a total of 416 genes (189 up- and 227 downregulated) to be altered by SNEB. Network analysis using Ingenuity Pathway Analysis revealed that SNEB was associated with widespread changes in gene expression classified into 36 gene networks including those associated with lipid metabolism, connective tissue development and function, cell signaling, cell cycle, and metabolic diseases, the three most significant of which are discussed in detail. SNEB cows displayed reduced expression of transcription activators and signal transducers that regulate the expression of genes and gene networks associated with cell signaling and tissue repair. These alterations are linked with increased expression of abnormal cell cycle and cellular proliferation associated pathways. This study provides new information and insights on the effect of SNEB on gene expression in high-yielding Holstein Friesian dairy cows in the early postpartum period.

  15. Rational design, high-yield synthesis, and low thermal conductivity of Te/Bi{sub 2}Te{sub 3} core/shell heterostructure nanotube composites

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhiliang; Zheng, Shuqi, E-mail: zhengsq09@163.com; Huang, Ting; Zhang, Yuzhuo; Teng, Renyuan; Lu, Guiwu

    2014-12-25

    Graphical abstract: The Te/Bi{sub 2}Te{sub 3} core/shell heterostructure nanotubes with serrate interface and enhanced phonon scattering were synthesized by an in-situ growth method. - Highlights: • Te/Bi{sub 2}Te{sub 3} core/shell heterostructure nanotubes were rationally designed and synthesized. • Mass products were obtained by the high-yield two-step solution phase method. • The rough serrated interfaces were in favor of increasing phonon scatterings. • The composites own ultralow thermal conductivities at near room temperatures. • The design, method and structure may be instructive to other materials. - Abstract: Te/Bi{sub 2}Te{sub 3} core/shell heterostructure nanotube (NT) composites with rough serrated interfaces, and hollow structures were designed and synthesized to enhance phonon scattering. A conventional two-step solution phase method was used to synthesize the mass products in high-yield. The external diameter and wall thickness of the NTs measured approximately 250 nm and 60 nm, and their lengths ranged from 7 μm to 9 μm. The hexagonal phase Te core, rhombohedral phase Bi{sub 2}Te{sub 3} shell, hollow structure, and saw-toothed interface were accurately determined through X-ray diffraction, scanning electron microscopy and transmission emission microscopy. Relatively stable and low thermal conductivities (from 0.43 Wm{sup −1} K{sup −1} to 0.46 Wm{sup −1} K{sup −1}) were obtained when the temperatures increased from 300 K to 400 K (near room temperatures). Finally, this research systematically examined the formation mechanisms based on the in situ growth method and the phonon scattering occurring in both the hollow structures and on the saw-toothed interface.

  16. 高产黄色素红曲霉菌株的诱变选育%Mutation Breeding of Monascus with High-yielding Yellow Pigment

    Institute of Scientific and Technical Information of China (English)

    赵建博; 王伟平; 李改; 曾乐平; 杨建

    2014-01-01

    To obtain the strain with high-yielding yellow pigment,Monascus SE0 1 is treated by UV mutagenesis,different concentration of hydrogen peroxide and LiCl complex mutation methods.The results show that,under the complex mutation conditions of UV radiation of 60 s and 0.12% LiCl, Monascus SE1 9 is found to be high-yielding yellow pigment producer,and its yellow pigment reaches 57.1 U/mL through liquid-state fermentation,which is 5.54 times higher than that of the start strain SE01,and the stable heritability of selected strain is still well after inoculated for 5 generations.%以红曲霉菌株Monascus SE01为出发菌株,利用紫外线诱变、双氧水筛选和氯化锂复合诱变的方法,选育得到高产黄色素的红曲霉突变株。实验结果表明:在紫外线照射60 s、氯化锂质量分数为0.12%的复合诱变条件下得到的菌株 SE19,经液态发酵后黄色素高达57.1 U/mL,与出发菌株相比,黄色素色价提高了5.54倍。该菌株5代接种后,其黄色素产量相对稳定。

  17. Drug and Therapeutics (D & T) committees in Dutch hospitals : a nation-wide survey of structure, activities, and drug selection procedures

    NARCIS (Netherlands)

    Fijn, R; Brouwers, JRBJ; Knaap, RJ; De Jong-Van den Berg, LTW

    1999-01-01

    Aims To determine structure, activities and drug selection processes used by Dutch hospital drug and therapeutics (D & T) committees. Methods A pretested structured survey questionnaire based on the Australian process and impact indicators, previous research, and consultation of professionals was de

  18. Neutron signal transfer analysis

    CERN Document Server

    Pleinert, H; Lehmann, E

    1999-01-01

    A new method called neutron signal transfer analysis has been developed for quantitative determination of hydrogenous distributions from neutron radiographic measurements. The technique is based on a model which describes the detector signal obtained in the measurement as a result of the action of three different mechanisms expressed by signal transfer functions. The explicit forms of the signal transfer functions are determined by Monte Carlo computer simulations and contain only the distribution as a variable. Therefore an unknown distribution can be determined from the detector signal by recursive iteration. This technique provides a simple and efficient tool for analysis of this type while also taking into account complex effects due to the energy dependency of neutron interaction and single and multiple scattering. Therefore this method provides an efficient tool for precise quantitative analysis using neutron radiography, as for example quantitative determination of moisture distributions in porous buil...

  19. Temperature of neutron stars

    Science.gov (United States)

    Tsuruta, Sachiko

    2016-07-01

    We start with a brief introduction to the historical background in the early pioneering days when the first neutron star thermal evolution calculations predicted the presence of neutron stars hot enough to be observable. We then report on the first detection of neutron star temperatures by ROSAT X-ray satellite, which vindicated the earlier prediction of hot neutron stars. We proceed to present subsequent developments, both in theory and observation, up to today. We then discuss the current status and the future prospect, which will offer useful insight to the understanding of basic properties of ultra-high density matter beyond the nuclear density, such as the possible presence of such exotic particles as pion condensates.

  20. Decoherence Free Neutron Interferometry

    CERN Document Server

    Pushin, Dmitry A; Cory, David G

    2016-01-01

    Perfect single-crystal neutron interferometers are adversely sensitive to environmental disturbances, particularly mechanical vibrations. The sensitivity to vibrations results from the slow velocity of thermal neutrons and the long measurement time that are encountered in a typical experiment. Consequently, to achieve a good interference solutions for reducing vibration other than those normally used in optical experiments must be explored. Here we introduce a geometry for a neutron interferometer that is less sensitive to low-frequency vibrations. This design may be compared with both dynamical decoupling methods and decoherence-free subspaces that are described in quantum information processing. By removing the need for bulky vibration isolation setups, this design will make it easier to adopt neutron interferometry to a wide range of applications and increase its sensitivity.

  1. Neutron Stars Recent Developments

    CERN Document Server

    Heiselberg, H

    1999-01-01

    Recent developments in neutron star theory and observation are discussed. Based on modern nucleon-nucleon potentials more reliable equations of state for dense nuclear matter have been constructed. Furthermore, phase transitions such as pion, kaon and hyperon condensation, superfluidity and quark matter can occur in cores of neutron stars. Specifically, the nuclear to quark matter phase transition and its mixed phases with intriguing structures is treated. Rotating neutron stars with and without phase transitions are discussed and compared to observed masses, radii and glitches. The observations of possible heavy $\\sim 2M_\\odot$ neutron stars in X-ray binaries and QPO's require relatively stiff equation of states and restrict strong phase transitions to occur at very high nuclear densities only.

  2. The intense neutron generator

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, W.B

    1966-07-01

    The presentation discusses both the economic and research contexts that would be served by producing neutrons in gram quantities at high intensities by electrical means without uranium-235. The revenue from producing radioisotopes is attractive. The array of techniques introduced by the multipurpose 65 megawatt Intense Neutron Generator project includes liquid metal cooling, superconducting magnets for beam bending and focussing, super-conductors for low-loss high-power radiofrequency systems, efficient devices for producing radiofrequency power, plasma physics developments for producing and accelerating hydrogen, ions at high intensity that are still far out from established practice, a multimegawatt high voltage D.C. generating machine that could have several applications. The research fields served relate principally to materials science through neutron-phonon and other quantum interactions as well as through neutron diffraction. Nuclear physics is served through {mu}-, {pi}- and K-meson production. Isotope production enters many fields of applied research. (author)

  3. Introduction to neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W.E. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-11-01

    We give here an introduction to the theoretical principles of neutron scattering. The relationship between scattering- and correlation-functions is particularly emphasized. Within the framework of linear response theory (justified by the weakness of the basic interaction) the relation between fluctuation and dissipation is discussed. This general framework explains the particular power of neutron scattering as an experimental method. (author) 4 figs., 4 refs.

  4. Neutron scattering in dimers

    DEFF Research Database (Denmark)

    Gudel, H. U.; Furrer, A.; Kjems, Jørgen

    1986-01-01

    Insulating compounds containing dimers of transition metal and rare earth ions have been studied by inelastic neutron scattering (INS). Energy splittings can be directly determined, and the corresponding parameters are easily extracted from the experimental data. The intensities of dimer excitati......Insulating compounds containing dimers of transition metal and rare earth ions have been studied by inelastic neutron scattering (INS). Energy splittings can be directly determined, and the corresponding parameters are easily extracted from the experimental data. The intensities of dimer...

  5. Pulsed spallation Neutron Sources

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, J.M. [Argonne National Lab., IL (United States)

    1994-12-31

    This paper reviews the early history of pulsed spallation neutron source development at Argonne and provides an overview of existing sources world wide. A number of proposals for machines more powerful than currently exist are under development, which are briefly described. The author reviews the status of the Intense Pulsed Neutron Source, its instrumentation, and its user program, and provides a few examples of applications in fundamental condensed matter physics, materials science and technology.

  6. Neutron scattering in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Knott, R.B. [Australian Nuclear Science and Technology Organisation, Menai (Australia)

    1994-12-31

    Neutron scattering techniques have been part of the Australian scientific research community for the past three decades. The High Flux Australian Reactor (HIFAR) is a multi-use facility of modest performance that provides the only neutron source in the country suitable for neutron scattering. The limitations of HIFAR have been recognized and recently a Government initiated inquiry sought to evaluate the future needs of a neutron source. In essence, the inquiry suggested that a delay of several years would enable a number of key issues to be resolved, and therefore a more appropriate decision made. In the meantime, use of the present source is being optimized, and where necessary research is being undertaken at major overseas neutron facilities either on a formal or informal basis. Australia has, at present, a formal agreement with the Rutherford Appleton Laboratory (UK) for access to the spallation source ISIS. Various aspects of neutron scattering have been implemented on HIFAR, including investigations of the structure of biological relevant molecules. One aspect of these investigations will be presented. Preliminary results from a study of the interaction of the immunosuppressant drug, cyclosporin-A, with reconstituted membranes suggest that the hydrophobic drug interdigitated with lipid chains.

  7. Coded source neutron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, Philip R [ORNL; Santos-Villalobos, Hector J [ORNL

    2011-01-01

    Coded aperture techniques have been applied to neutron radiography to address limitations in neutron flux and resolution of neutron detectors in a system labeled coded source imaging (CSI). By coding the neutron source, a magnified imaging system is designed with small spot size aperture holes (10 and 100 m) for improved resolution beyond the detector limits and with many holes in the aperture (50% open) to account for flux losses due to the small pinhole size. An introduction to neutron radiography and coded aperture imaging is presented. A system design is developed for a CSI system with a development of equations for limitations on the system based on the coded image requirements and the neutron source characteristics of size and divergence. Simulation has been applied to the design using McStas to provide qualitative measures of performance with simulations of pinhole array objects followed by a quantitative measure through simulation of a tilted edge and calculation of the modulation transfer function (MTF) from the line spread function. MTF results for both 100um and 10um aperture hole diameters show resolutions matching the hole diameters.

  8. Coded source neutron imaging

    Science.gov (United States)

    Bingham, Philip; Santos-Villalobos, Hector; Tobin, Ken

    2011-03-01

    Coded aperture techniques have been applied to neutron radiography to address limitations in neutron flux and resolution of neutron detectors in a system labeled coded source imaging (CSI). By coding the neutron source, a magnified imaging system is designed with small spot size aperture holes (10 and 100μm) for improved resolution beyond the detector limits and with many holes in the aperture (50% open) to account for flux losses due to the small pinhole size. An introduction to neutron radiography and coded aperture imaging is presented. A system design is developed for a CSI system with a development of equations for limitations on the system based on the coded image requirements and the neutron source characteristics of size and divergence. Simulation has been applied to the design using McStas to provide qualitative measures of performance with simulations of pinhole array objects followed by a quantitative measure through simulation of a tilted edge and calculation of the modulation transfer function (MTF) from the line spread function. MTF results for both 100μm and 10μm aperture hole diameters show resolutions matching the hole diameters.

  9. Neutron Nucleic Acid Crystallography.

    Science.gov (United States)

    Chatake, Toshiyuki

    2016-01-01

    The hydration shells surrounding nucleic acids and hydrogen-bonding networks involving water molecules and nucleic acids are essential interactions for the structural stability and function of nucleic acids. Water molecules in the hydration shells influence various conformations of DNA and RNA by specific hydrogen-bonding networks, which often contribute to the chemical reactivity and molecular recognition of nucleic acids. However, X-ray crystallography could not provide a complete description of structural information with respect to hydrogen bonds. Indeed, X-ray crystallography is a powerful tool for determining the locations of water molecules, i.e., the location of the oxygen atom of H2O; however, it is very difficult to determine the orientation of the water molecules, i.e., the orientation of the two hydrogen atoms of H2O, because X-ray scattering from the hydrogen atom is very small.Neutron crystallography is a specialized tool for determining the positions of hydrogen atoms. Neutrons are not diffracted by electrons, but are diffracted by atomic nuclei; accordingly, neutron scattering lengths of hydrogen and its isotopes are comparable to those of non-hydrogen atoms. Therefore, neutron crystallography can determine both of the locations and orientations of water molecules. This chapter describes the current status of neutron nucleic acid crystallographic research as well as the basic principles of neutron diffraction experiments performed on nucleic acid crystals: materials, crystallization, diffraction experiments, and structure determination.

  10. Evaluation of antibodies to thymine ROS-modified DNA poly(dT), in patients with immunologic disorders: relationships to anti n-DNA and anti ENA autoantibodies.

    Science.gov (United States)

    Brusca, I; Li Vigni, P; Sucato, R; Cilluffo, N; La Chiusa, S M

    2002-03-01

    Hydroxyl radical, one of the most potent of all reactive oxygen species, is known to modify adenine and thymine in cellular DNA, producing some modified DNA fragments (ROS-DNA) with different antigenic properties. Despite several in vitro studies about ROS-DNA, data regarding their clinical significance are scanty. The aim of our study was to seek out the presence and clinical significance of the anti poly(dT) auto-antibodies in a group of patients suspected of autoimmune disease. We initially evaluated more than 900 consecutive sera of hospitalized patients (range age from 6 to 70 yrs) referred to our laboratory during 18 months. Anti n-DNA, anti-ENA and poly(dT) autoantibodies were performed on 158 ANA positive sera and 28 ANA negative sera from patients strongly suspected of rheumatic diseases or affected by HCV infection. Anti poly (dT) were found in 22 out of 186 sera. As regards the clinical evaluation, 8 patients were affected by SLE, 5 by Scleroderma, 3 by HCV-related chronic hepatitis, 4 by recurrent abortions (without presence of the anti-cardiolipin antibodies and other clinical symptoms). In two patients the ACR criteria and the clinical aspects did not allow a definite diagnosis. Anti-Histones were detected in 18 out of 22 poly (dT) positive patients. Our data suggest that anti poly(dT) autoantibodies are sensitive markers of various autoimmune diseases, but with a minor specificity as compared to anti n-DNA for the diagnosis of SLE.

  11. Influence of neutron irradiation on the tritium retention in beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Rolli, R.; Ruebel, S.; Werle, H. [Forschungszentrum Karlsruhe, Inst. fuer Neutronenphysik und Reaktortechnik, Karlsruhe (Germany); Wu, C.H.

    1998-01-01

    Carbon-based materials and beryllium are the candidates for protective layers on the components of fusion reactors facing plasma. In contact with D-T plasma, these materials absorb tritium, and it is anticipated that tritium retention increases with the neutron damage due to neutron-induced traps. Because of the poor data base for beryllium, the work was concentrated on it. Tritium was loaded into the samples from stagnant T{sub 2}/H{sub 2} atmosphere, and afterwards, the quantity of the loaded tritium was determined by purged thermal annealing. The specification of the samples is shown. The samples were analyzed by SEM before and after irradiation. The loading and the annealing equipments are contained in two different glove boxes with N{sub 2} inert atmosphere. The methods of loading and annealing are explained. The separation of neutron-produced and loaded tritium and the determination of loaded tritium in irradiated samples are reported. Also the determination of loaded tritium in unirradiated samples is reported. It is evident that irradiated samples contained much more loaded tritium than unirradiated samples. The main results of this investigation are summarized in the table. (K.I.)

  12. MAGNETIC NEUTRON SCATTERING

    Energy Technology Data Exchange (ETDEWEB)

    ZALIZNYAK,I.A.; LEE,S.H.

    2004-07-30

    Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern

  13. MAGNETIC NEUTRON SCATTERING

    Energy Technology Data Exchange (ETDEWEB)

    ZALIZNYAK,I.A.; LEE,S.H.

    2004-07-30

    Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern

  14. Fundamental neutron physics at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Greene, G.

    1995-10-01

    Modern neutron sources and science share a common origin in mid-20th-century scientific investigations concerned with the study of the fundamental interactions between elementary particles. Since the time of that common origin, neutron science and the study of elementary particles have evolved into quite disparate disciplines. The neutron became recognized as a powerful tool for studying condensed matter with modern neutron sources being primarily used (and justified) as tools for neutron scattering and materials science research. The study of elementary particles has, of course, led to the development of rather different tools and is now dominated by activities performed at extremely high energies. Notwithstanding this trend, the study of fundamental interactions using neutrons has continued and remains a vigorous activity at many contemporary neutron sources. This research, like neutron scattering research, has benefited enormously by the development of modern high-flux neutron facilities. Future sources, particularly high-power spallation sources, offer exciting possibilities for continuing this research.

  15. Radiography with polarised neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Michael L.

    2010-08-20

    In this thesis I present a new technique for the spatially resolved investigation of the magnetic properties of bulk samples. Standard one dimensional neutron depolarisation analysis is combined with neutron radiography to a method we call Neutron Depolarisation Imaging (NDI). The experimental setup which was installed at the neutron radiography beam line ANTARES at FRM II consists of a double crystal monochromator, neutron polariser, spin flipper, polarisation analyser and a position sensitive CCD detector. A comprehensive discussion of the requirements for these components is given and the limitations of the method are shown. The maximum spatial resolution which can be achieved with a neutron radiography setup is determined by the collimation of the neutron beam and the distance between sample and detector. Different types of polarisers have been tested and their advantages and disadvantages are discussed. A double crystal monochromator and a new type of polariser employing polarising neutron supermirrors based on the principle of an optical periscope were developed and tested during this work. Furthermore, NDI measurements on various samples of the weakly ferromagnetic materials Pd{sub 1-x}Ni{sub x} and Ni{sub 3}Al are presented. Neutron depolarisation radiography and tomography measurements were conducted with a spatial resolution as high as 0.3 mm on Pd{sub 1-x}Ni{sub x} and Ni{sub 3}Al samples. The feasibility of NDI experiments under hydrostatic pressures up to 10 kbar was shown on a sample of Ni{sub 3}Al using a modified Cu:Be clamp cell. A decrease of the ordering temperature by 2 K under hydrostatic pressure was determined from the NDI measurements and shows the potential of the method for further high pressure experiments. Additionally a method was developed which in principle allows to obtain the intrinsic dependence of the ordering temperature T{sub C} on the ordered moment Ms from NDI measurements on inhomogeneous samples containing regions with

  16. Comparison of bulk and pitcher-catcher targets for laser-driven neutron production

    Science.gov (United States)

    Willingale, L.; Petrov, G. M.; Maksimchuk, A.; Davis, J.; Freeman, R. R.; Joglekar, A. S.; Matsuoka, T.; Murphy, C. D.; Ovchinnikov, V. M.; Thomas, A. G. R.; Van Woerkom, L.; Krushelnick, K.

    2011-08-01

    Laser-driven d(d, n)-3He beam-target fusion neutron production from bulk deuterated plastic (CD) targets is compared with a pitcher-catcher target scheme using an identical laser and detector arrangement. For laser intensities in the range of (1-3) × 1019 W cm-2, it was found that the bulk targets produced a high yield (5 × 104 neutrons per steradian) beamed preferentially in the laser propagation direction. Numerical modeling shows the importance of considering the temperature adjusted stopping powers to correctly model the neutron production. The bulk CD targets have a high background target temperature leading to a reduced stopping power for the deuterons, which increases the probability of generating neutrons by fusion. Neutron production from the pitcher-catcher targets was not as efficient since it does not benefit from the reduced stopping power in the cold catcher target. Also, the inhibition of the deuteron acceleration by a proton rich contamination layer significantly reduces the pitcher-catcher neutron production.

  17. Neutron-Induced Failures in Semiconductor Devices

    Energy Technology Data Exchange (ETDEWEB)

    Wender, Stephen Arthur [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-06

    This slide presentation explores single event effect, environmental neutron flux, system response, the Los Alamos Neutron Science Center (LANSCE) neutron testing facility, examples of SEE measurements, and recent interest in thermal neutrons.

  18. Neutron drip transition in accreting and nonaccreting neutron star crusts

    CERN Document Server

    Chamel, N; Zdunik, J L; Haensel, P

    2015-01-01

    The neutron-drip transition in the dense matter constituting the interior of neutron stars generally refers to the appearance of unbound neutrons as the matter density reaches some threshold density $\\rho_\\textrm{drip}$. This transition has been mainly studied under the cold catalyzed matter hypothesis. However, this assumption is unrealistic for accreting neutron stars. After examining the physical processes that are thought to be allowed in both accreting and nonaccreting neutron stars, suitable conditions for the onset of neutron drip are derived and general analytical expressions for the neutron drip density and pressure are obtained. Moreover, we show that the neutron-drip transition occurs at lower density and pressure than those predicted within the mean-nucleus approximation. This transition is studied numerically for various initial composition of the ashes from X-ray bursts and superbursts using microscopic nuclear mass models.

  19. [Effects of nitrogen application period on the nitrogen metabolism key enzymes activities and antioxidant characteristics of high-yielding summer maize].

    Science.gov (United States)

    Lü, Peng; Zhang, Ji-Wang; Liu, Wei; Yang, Jin-Sheng; Dong, Shu-Ting; Liu, Peng; Li, Deng-Hai

    2012-06-01

    Taking the high-yielding summer maize cultivars Denghai 661 (DH661) and Zhengdan 958 (ZD958) as test materials, a field experiment was conducted to study their grain yield, nitrogen use efficiency, key enzymes activities of nitrogen metabolism, and antioxidant enzymes activities under effects of different nitrogen application periods. One-dose nitrogen application at jointing stage was not beneficial to the increase of grain yield and the nitrogen accumulation in plant and grain, while split application in combination with application after anthesis increased the nitrogen accumulation in plant and grain significantly and increased the grain yield. When the nitrogen was applied at a ratio of 2:4:4 at jointing stage, 10-leaf stage, and 10 days after anthesis, the grain yield of DH661 was up to 14123.0 kg x hm(-2); when the nitrogen was applied at a ratio of 1:2:5:2 as the basal and at jointing stage, 10-leaf stage, and 10 days after anthesis, the grain yield of ZD958 was up to 14517.1 kg x hm(-2). These two nitrogen application modes increased the grain yield of DH661 and ZD958 by 14.5% and 17.5%, respectively, as compared with one-dose nitrogen application at jointing stage. Split nitrogen application before anthesis increased plant nitrate reductase activity significantly. In the 0-42 days after anthesis under split nitrogen application, the glutamine synthetase, glutamate synthase, and glutamate dehydrogenase activities of DH661 and ZD958 were averagely increased by 32.6%, 47.1% and 50.4%, and 14.5%, 61.8% and 25.6%, and the superoxide dismutase and catalase activities were increased by 22. 0% and 36.6%, and 13.4% and 62.0%, respectively, and the malondialdehyde content was decreased significantly, as compared with one-off nitrogen application. It was suggested that for the high-yielding of summer maize, split application of nitrogen and appropriately increasing the nitrogen application ratio after anthesis could enhance the plant key nitrogen metabolism enzymes

  20. Influence of the neutron transport tube on neutron resonance densitometry

    Directory of Open Access Journals (Sweden)

    Kitatani Fumito

    2017-01-01

    Full Text Available Neutron Resonance Densitometry (NRD is a non-destructive assay technique of nuclear materials in particle-like debris that contains various materials. An aim of NRD is to quantify nuclear materials in a melting fuel of Fukusima Daiichi plant, spent nuclear fuel and annihilation disposal fuel etc. NRD consists of two techniques of Neutron Resonance Transmission Analysis (NRTA and Neutron Resonance Capture Analysis (NRCA or Prompt Gamma-ray Analysis (PGA. A density of nuclear material isotopes is decided with NRTA. The materials absorbing a neutron in a wide energy range such as boron in a sample are identified by NRCA/PGA. The information of NRCA/PGA is used in NRTA analysis to quantify nuclear material isotopes. A neutron time of flight (TOF method is used in NRD measurements. A facility, consisting of a neutron source, a neutron flight path, and a detector is required. A short flight path and a strong neutron source are needed to downsize such a facility and put NRD into practical use. A neutron transport tube covers a flight path to prevent noises. In order to investigate the effect of neutron transport tube and pulse width of a neutron source, we carried out NRTA experiments with a 2-m short neutron transport tube constructed at Kyoto University Research Reactor Institute - Linear Accelerator (KURRI-LINAC, and impacts of shield of neutron transport tube and influence of pulse width of a neutron source were examined. A shield of the neutron transport tube reduced a background and had a good influence on the measurement. The resonance dips of 183W at 27 eV was successfully observed with a pulse width of a neutron source less than 2 μs.

  1. Axial Neutron Flux Evaluation in a Tokamak System: a Possible Transmutation Blanket Position for a Fusion-Fission Transmutation System

    Science.gov (United States)

    Velasquez, Carlos E.; de P. Barros, Graiciany; Pereira, Claubia; Fortini Veloso, Maria A.; Costa, Antonella L.

    2012-08-01

    A sub-critical advanced reactor based on Tokamak technology with a D-T fusion neutron source is an innovative type of nuclear system. Due to the large number of neutrons produced by fusion reactions, such a system could be useful in the transmutation process of transuranic elements (Pu and minor actinides (MAs)). However, to enhance the MA transmutation efficiency, it is necessary to have a large neutron wall loading (high neutron fluence) with a broad energy spectrum in the fast neutron energy region. Therefore, it is necessary to know and define the neutron fluence along the radial axis and its characteristics. In this work, the neutron flux and the interaction frequency along the radial axis are evaluated for various materials used to build the first wall. W alloy, beryllium, and the combination of both were studied, and the regions more suitable to transmutation were determined. The results demonstrated that the best zone in which to place a transmutation blanket is limited by the heat sink and the shield block. Material arrangements of W alloy/W alloy and W alloy/beryllium would be able to meet the requirements of the high fluence and hard spectrum that are needed for transuranic transmutation. The system was simulated using the MCNP code, data from the ITER Final Design Report, 2001, and the Fusion Evaluated Nuclear Data Library/MC-2.1 nuclear data library.

  2. Inference of total DT fusion neutron yield from prompt gamma-ray measurements at the National Ignition Facility

    Science.gov (United States)

    Church, J. A.; Herrmann, H. W.; Stoeffl, W.; Caggiano, J. A.; Cerjan, C.; Sayre, D.

    2014-10-01

    Prompt D-T fusion gamma-rays measured at the National Ignition Facility (NIF) with the Gamma-ray Reaction History detector (GRH) have been used recently to infer the total DT fusion neutron yield of inertial confinement fusion (ICF) implosions. DT fusion produces energetic gamma-rays (16.75 MeV) with a small branching ratio of approximately (4.2 +/- 2.0)e-5 γ/n. While the large error bar precludes use of the branching ratio for an accurate yield determination, the gamma-rays themselves provide the most unperturbed measure of fusion burn and can be used for such a purpose. A cross-calibration for the DT fusion gamma-ray to neutron signal is obtained via low areal density exploding pusher implosions which have mostly unperturbed neutron and gamma-ray signals. The calibration is then used to infer total DT neutron yield from gamma-ray measurements on high areal-density, cryogenically layered implosions in which neutrons are heavily down-scattered (up to 30%). Furthermore, the difference between the gamma-ray inferred total DT yield and the primary neutron yield (unscattered neutrons) can be used to estimate the total down-scatter fraction. Error analysis and comparison of yield values will be presented. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, LLNL-ABS-657694.

  3. Hybrid superconducting neutron detectors

    Energy Technology Data Exchange (ETDEWEB)

    Merlo, V.; Lucci, M.; Ottaviani, I. [Dipartimento di Fisica, Università Tor Vergata, Via della Ricerca Scientifica, I-00133 Roma (Italy); Salvato, M.; Cirillo, M. [Dipartimento di Fisica, Università Tor Vergata, Via della Ricerca Scientifica, I-00133 Roma (Italy); CNR SPIN Salerno, Università di Salerno, Via Giovanni Paolo II, n.132, 84084 Fisciano (Italy); Scherillo, A. [Science and Technology Facility Council, ISIS Facility Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Celentano, G. [ENEA Frascati Research Centre, Via. E. Fermi 45, 00044 Frascati (Italy); Pietropaolo, A., E-mail: antonino.pietropaolo@enea.it [ENEA Frascati Research Centre, Via. E. Fermi 45, 00044 Frascati (Italy); Mediterranean Institute of Fundamental Physics, Via Appia Nuova 31, 00040 Marino, Roma (Italy)

    2015-03-16

    A neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction, {sup 10}B + n → α + {sup 7}Li, with α and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T = 8 K and current-biased below the critical current I{sub c}, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40 mV are measured while the bias current can be properly modulated to bring the strip back to the superconducting state, thus resetting the detector. Measurements on the counting rate of the device are presented and the basic physical features of the detector are discussed.

  4. Hybrid Superconducting Neutron Detectors

    CERN Document Server

    Merlo, V; Cirillo, M; Lucci, M; Ottaviani, I; Scherillo, A; Celentano, G; Pietropaolo, A

    2014-01-01

    A new neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction 10B+n $\\rightarrow$ $\\alpha$+ 7Li , with $\\alpha$ and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T = 8 K and current-biased below the critical current Ic, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40 mV are measured while the bias current can be properly modulated to bring the strip back to the supercond...

  5. Neutron counting with cameras

    Energy Technology Data Exchange (ETDEWEB)

    Van Esch, Patrick; Crisanti, Marta; Mutti, Paolo [Institut Laue Langevin, Grenoble (France)

    2015-07-01

    A research project is presented in which we aim at counting individual neutrons with CCD-like cameras. We explore theoretically a technique that allows us to use imaging detectors as counting detectors at lower counting rates, and transits smoothly to continuous imaging at higher counting rates. As such, the hope is to combine the good background rejection properties of standard neutron counting detectors with the absence of dead time of integrating neutron imaging cameras as well as their very good spatial resolution. Compared to Xray detection, the essence of thermal neutron detection is the nuclear conversion reaction. The released energies involved are of the order of a few MeV, while X-ray detection releases energies of the order of the photon energy, which is in the 10 KeV range. Thanks to advances in camera technology which have resulted in increased quantum efficiency, lower noise, as well as increased frame rate up to 100 fps for CMOS-type cameras, this more than 100-fold higher available detection energy implies that the individual neutron detection light signal can be significantly above the noise level, as such allowing for discrimination and individual counting, which is hard to achieve with X-rays. The time scale of CMOS-type cameras doesn't allow one to consider time-of-flight measurements, but kinetic experiments in the 10 ms range are possible. The theory is next confronted to the first experimental results. (authors)

  6. Neutron whispering gallery

    Science.gov (United States)

    Nesvizhevsky, Valery V.; Voronin, Alexei Yu.; Cubitt, Robert; Protasov, Konstantin V.

    2010-02-01

    The `whispering gallery' effect has been known since ancient times for sound waves in air, later in water and more recently for a broad range of electromagnetic waves: radio, optics, Roentgen and so on. It consists of wave localization near a curved reflecting surface and is expected for waves of various natures, for instance, for atoms and neutrons. For matter waves, it would include a new feature: a massive particle would be settled in quantum states, with parameters depending on its mass. Here, we present for the first time the quantum whispering-gallery effect for cold neutrons. This phenomenon provides an example of an exactly solvable problem analogous to the `quantum bouncer'; it is complementary to the recently discovered gravitationally bound quantum states of neutrons . These two phenomena provide a direct demonstration of the weak equivalence principle for a massive particle in a pure quantum state. Deeply bound whispering-gallery states are long-living and weakly sensitive to surface potential; highly excited states are short-living and very sensitive to the wall potential shape. Therefore, they are a promising tool for studying fundamental neutron-matter interactions, quantum neutron optics and surface physics effects.

  7. Measurement of Fission Product Yields from Fast-Neutron Fission

    Science.gov (United States)

    Arnold, C. W.; Bond, E. M.; Bredeweg, T. A.; Fowler, M. M.; Moody, W. A.; Rusev, G.; Vieira, D. J.; Wilhelmy, J. B.; Becker, J. A.; Henderson, R.; Kenneally, J.; Macri, R.; McNabb, D.; Ryan, C.; Sheets, S.; Stoyer, M. A.; Tonchev, A. P.; Bhatia, C.; Bhike, M.; Fallin, B.; Gooden, M. E.; Howell, C. R.; Kelley, J. H.; Tornow, W.

    2014-09-01

    One of the aims of the Stockpile Stewardship Program is a reduction of the uncertainties on fission data used for analyzing nuclear test data [1,2]. Fission products such as 147Nd are convenient for determining fission yields because of their relatively high yield per fission (about 2%) and long half-life (10.98 days). A scientific program for measuring fission product yields from 235U,238U and 239Pu targets as a function of bombarding neutron energy (0.1 to 15 MeV) is currently underway using monoenergetic neutron beams produced at the 10 MV Tandem Accelerator at TUNL. Dual-fission chambers are used to determine the rate of fission in targets during activation. Activated targets are counted in highly shielded HPGe detectors over a period of several weeks to identify decaying fission products. To date, data have been collected at neutron bombarding energies 4.6, 9.0, 14.5 and 14.8 MeV. Experimental methods and data reduction techniques are discussed, and some preliminary results are presented.

  8. Fuel enrichment and temperature distribution in nuclear fuel rod in (D-T) driven hybrid reactor system

    Energy Technology Data Exchange (ETDEWEB)

    Osman, Ypek [Suleyman Demirel Universitesi Muhendislik-Mimarlyk Fakultesi, Isparta (Turkey)

    2001-07-01

    In this study, melting point of the fuel rod and temperature distribution in nuclear fuel rod are investigated for different coolants under various first wall loads (P{sub w}, =5, 6, 7, 8, 9, and 10 MWm{sup -2}) in Fusion-Fission reactor fueled with 50%LWR +50%CANDU. The fusion source of neutrons of 14.1 MeV is simulated by a movable target along the main axis of cylindrical geometry as a line source. In addition, the fusion chamber was thought as a cylindrical cavity with a diameter of 300 cm that is comparatively small value. The fissile fuel zone is considered to be cooled with four different coolants, gas, flibe (Li{sub 2}BeF{sub 4}), natural lithium (Li), and eutectic lithium (Li{sub 17}Pb{sub 83}). Investigations are observed during 4 years for discrete time intervals of{delta}t= 0.5 month and by a plant factor (PF) of 75%. Volumetric ratio of coolant-to fuel is 1:1, 45.515% coolant, 45.515% fuel, 8.971% clad, in fuel zone. (author)

  9. Single neutron pick-up on {sup 104}Pd

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, M.R.D.; Andre, J.P.A.M. de; Borello-Lewin, T.; Horodynski-Matsushigue, L.B.; Duarte, J.L.M.; Rodrigues, C.L. [Universidade de Sao Paulo, SP (Brazil). Inst. de Fisica; Ukita, G.M. [Universidade de Santo Amaro, SP (Brazil). Faculdade de Psicologia

    2006-12-15

    Low-lying levels of {sup 103}Pd have been investigated through the (d,t) reaction on {sup 104}Pd, at an incident deuteron energy of 15.0 MeV. Outgoing particles were momentum analyzed by an Enge magnetic spectrograph and detected in nuclear emulsion plates, with an energy resolution of 8 keV. Previous (d,t) work suffered from a much worse resolution than that here achieved. A partial analysis of the data obtained is reported, referring to six out of the fourteen scattering angles for which data were obtained. Angular distributions associated with eight of the thirteen levels seen up to 1.1 MeV of excitation have been compared to DWBA one-neutron pick-up predictions. Both, the attributed excitation energy values and the transferred angular momenta are in excellent agreement with the results of other kind of experiments, as tabulated by the Nuclear Data Sheets. Some peculiar structure characteristics, associated with the yrast 5/2{sup +}, 3/2{sup +} and 7/2{sup +} states found in the Ru chain could be recognized also in {sup 103}Pd, pointing to the possibility of a more global understanding of this transitional mass region. (author)

  10. Sequential dark-photo fermentation and autotrophic microalgal growth for high-yield and CO{sub 2}-free biohydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Yung-Chung [Department of Chemical Engineering, National Cheng Kung University, Tainan 701 (China); Chen, Chun-Yen [Department of Chemical Engineering, National Cheng Kung University, Tainan 701 (China); Sustainable Environment Research Center, National Cheng Kung University, Tainan (China); Lee, Chi-Mei [Department of Environmental Engineering, National Chung Hsing University, Taichung (China); Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, Tainan 701 (China); Sustainable Environment Research Center, National Cheng Kung University, Tainan (China); Center for Biosciences and Biotechnology, National Cheng Kung University, Tainan (China)

    2010-10-15

    Dark fermentation, photo fermentation, and autotrophic microalgae cultivation were integrated to establish a high-yield and CO{sub 2}-free biohydrogen production system by using different feedstock. Among the four carbon sources examined, sucrose was the most effective for the sequential dark (with Clostridium butyricum CGS5) and photo (with Rhodopseudomonas palutris WP3-5) fermentation process. The sequential dark-photo fermentation was stably operated for nearly 80 days, giving a maximum H{sub 2} yield of 11.61 mol H{sub 2}/mol sucrose and a H{sub 2} production rate of 673.93 ml/h/l. The biogas produced from the sequential dark-photo fermentation (containing ca. 40.0% CO{sub 2}) was directly fed into a microalga culture (Chlorella vulgaris C-C) cultivated at 30 C under 60 {mu}mol/m{sup 2}/s illumination. The CO{sub 2} produced from the fermentation processes was completely consumed during the autotrophic growth of C. vulgaris C-C, resulting in a microalgal biomass concentration of 1999 mg/l composed mainly of 48.0% protein, 23.0% carbohydrate and 12.3% lipid. (author)

  11. Combining metabolic engineering and biocompatible chemistry for high-yield production of homo-diacetyl and homo-(S,S)-2,3-butanediol.

    Science.gov (United States)

    Liu, Jianming; Chan, Siu Hung Joshua; Brock-Nannestad, Theis; Chen, Jun; Lee, Sang Yup; Solem, Christian; Jensen, Peter Ruhdal

    2016-07-01

    Biocompatible chemistry is gaining increasing attention because of its potential within biotechnology for expanding the repertoire of biological transformations carried out by enzymes. Here we demonstrate how biocompatible chemistry can be used for synthesizing valuable compounds as well as for linking metabolic pathways to achieve redox balance and rescued growth. By comprehensive rerouting of metabolism, activation of respiration, and finally metal ion catalysis, we successfully managed to convert the homolactic bacterium Lactococcus lactis into a homo-diacetyl producer with high titer (95mM or 8.2g/L) and high yield (87% of the theoretical maximum). Subsequently, the pathway was extended to (S,S)-2,3-butanediol (S-BDO) through efficiently linking two metabolic pathways via chemical catalysis. This resulted in efficient homo-S-BDO production with a titer of 74mM (6.7g/L) S-BDO and a yield of 82%. The diacetyl and S-BDO production rates and yields obtained are the highest ever reported, demonstrating the promising combination of metabolic engineering and biocompatible chemistry as well as the great potential of L. lactis as a new production platform.

  12. 早稻高产施肥关键技术综述%Key Fertilization Techniques for High Yield of Early Rice

    Institute of Scientific and Technical Information of China (English)

    陈蔚; 谢保忠; 王万福; 张绍安; 余保生

    2011-01-01

    The key fertilization techniques for high yield of early rice, including scientific application of seedling fertilizers, cultivating strong seedling, use of appropriate principles of field fertilization patterns and fertilizer, enough field basal, early application of tillering fertilizer, skillfully applicating of panicle fertilizer according to plants. And the effect of each application of fertilizer on early rice growth and yield components of early rice was analyzed to guide rational fertilization.%阐述了早稻高产施肥的关键技术,包括秧田科学施肥,培育壮秧,采用适宜的大田施肥模式和施肥原则,施足大田基肥,早施分蘖肥,看苗巧施穗粒肥等;并分析了各次施肥对早稻生长发育和产量构成因素的作用,以期指导早稻的合理施肥.

  13. CHO-S antibody titers >1 gram/liter using flow electroporation-mediated transient gene expression followed by rapid migration to high-yield stable cell lines.

    Science.gov (United States)

    Steger, Krista; Brady, James; Wang, Weili; Duskin, Meg; Donato, Karen; Peshwa, Madhusudan

    2015-04-01

    In recent years, researchers have turned to transient gene expression (TGE) as an alternative to CHO stable cell line generation for early-stage antibody development. Despite advances in transfection methods and culture optimization, the majority of CHO-based TGE systems produce insufficient antibody titers for extensive use within biotherapeutic development pipelines. Flow electroporation using the MaxCyte STX Scalable Transfection System is a highly efficient, scalable means of CHO-based TGE for gram-level production of antibodies without the need for specialized expression vectors or genetically engineered CHO cell lines. CHO cell flow electroporation is easily scaled from milligram to multigram quantities without protocol reoptimization while maintaining transfection performance and antibody productivity. In this article, data are presented that demonstrate the reproducibility, scalability, and antibody production capabilities of CHO-based TGE using the MaxCyte STX. Data show optimization of posttransfection parameters such as cell density, media composition, and feed strategy that result in secreted antibody titers >1 g/L and production of multiple grams of antibody within 2 weeks of a single CHO-S cell transfection. In addition, data are presented to demonstrate the application of scalable electroporation for the rapid generation of high-yield stable CHO cell lines to bridge the gap between early- and late-stage antibody development activities.

  14. Bioproduction and optimization of rosmarinic acid production in Solenostemon scutellarioides through media manipulation and conservation of high yielding clone via encapsulation.

    Science.gov (United States)

    Sahu, Ranabir; Dewanjee, Saikat; Gangopadhyay, Moumita

    2013-09-01

    The present study describes the role of different exogenous phytohormones, polyamines and sucrose on growth and rosmarinic acid (RA) production in whole plant culture of Solenostemon scutellarioides. It was further aimed to conserve elite clones via synthetic seed technology. S. scutellarioides was treated either singly or in combination with different phytohormones. Cultures incubated with NAA (0.5 mg L(-1)) yielded the highest RA accumulation (g(-1FW)), but negatively affected the growth. So, overall RA content was insignificant. Cultures incubated with IBA, BAP and GA3 at low concentration significantly improved growth and RA bioaccumulation. In the combinatorial study, IBA+BAP+GA3 (0.5 mg L(-1) each) was found optimum for plant biomass and RA production (65.2% improvement of total RA). Amongst polyamines, putrescine (1 mg L(-1)) exhibited 20.4% improvement of total RA content. The intracellular RA accumulation (g(-1FW)) was significantly higher between 5 and 7% of sucrose concentrations. However, the total increase in RA content was inhibited due to deterioration of the culture with increasing sucrose concentration. Based on the effect of different treatments on growth and RA accumulation, a high yielding and stable plant line was selected for conservation via alginate encapsulation. Uniform shaped alginate coated synthetic seeds conserved up to 6 months exhibited high regeneration potential and RA content.

  15. Cloning, E. coli Expression and Molecular Analysis of Amorpha-4,11-Diene Synthase from a High-Yield Strain of Artemisia annua L.

    Institute of Scientific and Technical Information of China (English)

    Zhen-Qiu Li; Yan Liu; Ben-Ye Liu; Hong Wang; He-Chun Ye; Guo-Feng Li

    2006-01-01

    Increasing demand of artemisinin in the treatment of malaria has placed substantial stress on the total artemisinin supplies world-wide, so more attention has been paid to increasing the content of artemisinin in the Artemisia annua L. plant. In this study, amorpha-4, 11-diene synthase (ADS) cDNA (ads1) and genomics gene (gads1) were cloned from a high-yield A. annua strain 001. The activity of ADS1 was confirmed by heterogeneous overexpression of ads1 and in vitro enzymatic incubation. Reverse transcript-polymerase chain reaction results demonstrated that ads1 expressed in leaves, flowers and young stems, but not in roots. This organ-specific expression pattern of ads1 is consistent with that of artemisinin accumulation in the plant. The gads1 has a complex organization including seven exons and six introns, and belongs to class Ⅲ terpene synthase. DNA gel blotting revealed that the ADS gene has at least four copies in the genome of strain 001. The higher copy numbers might be one of the reasons for its high artemisinin content.

  16. High Yield Cultivation Technology of Smallanthus Sonchifolius in Benxi Area%本溪地区雪莲果高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    崔超

    2013-01-01

    以本溪县连财中药材种苗专业合作社为试验基地,探索适合本溪地区的雪莲果高产栽培技术。从产地环境、种球(苗)选用及处理、选地与整地、育苗、移栽、田间管理、虫害防治及收获等环节,介绍雪莲果高产栽培技术操作要点,为提高雪莲果产量提供参考。%Taking Benxi County Liancai traditional Chinese medicinal seeds and seedlings cooperatives as the test base, we explored the yacon high-yield cultivation technology in Benxi area. This article expounds on the operation points of cultivation technology of Smallan-thus sonchifolius from the perspectives of the environment of producing areas, seedball (seedlings) selection and processing, selection and preparation of ground, seedling, transplanting, field management, pest control and harvesting process to provide reference for improving yacon fruit yield.

  17. SUBSTITUTION OF HIGH-YIELD-PULP FOR HARDWOOD BLEACHED KRAFT PULP IN PAPER PRODUCTION AND ITS EFFECT ON ALKENYL SUCCINIC ANHYDRIDE SIZING

    Directory of Open Access Journals (Sweden)

    Qijie Chen,

    2012-02-01

    Full Text Available In recent years there has been an increasing interest in using high-yield pulp (HYP as a partial replacement for hardwood bleached kraft pulp (HWBKP in the production of high-quality fine papers as a cost-effective way of improving the product performance. This study investigated the substitution of HYP for HWBKP and its effect on the Alkenyl Succinic Anhydride (ASA sizing performance. The results showed that the substitution of an aspen HYP for HWBKP can increase the ASA sizing performance at a HYP substitution as high as 15 to 20%. The ASA addition sequence has an influence on the ASA sizing performance and first adding ASA to the HYP followed by mixing with kraft pulps was the preferred method. Using precipitated calcium carbonate (PCC as a paper filler at a dosage of less than 20% can increase the ASA sizing performance due to the contribution of the calcium soap of the hydrolysed ASA. A PCC dosage greater than 20% resulted in a negative impact on the sizing performance. It was also found that different PCC loading sequences can also affect the ASA sizing performance.

  18. 现代高产奶牛饲养管理要点%Feeding and management key points of modern high-yielding dairy cows

    Institute of Scientific and Technical Information of China (English)

    刘德权

    2014-01-01

    强化奶牛饲养管理,根据奶牛不同阶段地生理特点,采用不同的饲养管理手段,推行先进地科学饲养管理水平,不断提高奶牛的饲养管理水平,减少疾病发病率,同时降低成本、提高产量、增加效益,对提高奶牛养殖效益至关重要。%To strengthen the feeding and management of dairy cows, different means of feeding and management were applied according to physiological characteristics of different stages. The im-plementation of advanced scientific management methods, continuously improving the management lev-el of dairy cattle feeding and management, reducing the incidence of disease, at the same time, re-ducing the cost, improving the yield and increasing productive efficiency are very important for improve the feeding efficiency of high-yielding dairy cows.

  19. An Efficient Synthesis Strategy for Metal-Organic Frameworks: Dry-Gel Synthesis of MOF-74 Framework with High Yield and Improved Performance

    Science.gov (United States)

    Das, Atanu Kumar; Vemuri, Rama Sesha; Kutnyakov, Igor; McGrail, B. Peter; Motkuri, Radha Kishan

    2016-06-01

    Vapor-assisted dry-gel synthesis of the metal-organic framework-74 (MOF-74) structure, specifically Ni-MOF-74 produced from synthetic precursors using an organic-water hybrid solvent system, showed a very high yield (>90% with respect to 2,5-dihydroxyterepthalic acid) and enhanced performance. The Ni-MOF-74 obtained showed improved sorption characteristics towards CO2 and the refrigerant fluorocarbon dichlorodifluoromethane. Unlike conventional synthesis, which takes 72 hours using the tetrahydrofuran-water system, this kinetic study showed that Ni-MOF-74 forms within 12 hours under dry-gel conditions with similar performance characteristics, and exhibits its best performance characteristics even after 24 hours of heating. In the dry-gel conversion method, the physical separation of the solvent and precursor mixture allows for recycling of the solvent. We demonstrated efficient solvent recycling (up to three times) that resulted in significant cost benefits. The scaled-up manufacturing cost of Ni-MOF-74 synthesized via our dry-gel method is 45% of conventional synthesis cost. Thus, for bulk production of the MOFs, the proposed vapor-assisted, dry-gel method is efficient, simple, and inexpensive when compared to the conventional synthesis method.

  20. Achieving High Yield of Lactic Acid for Antimicrobial Characterization in Cephalosporin-Resistant Lactobacillus by the Co-Expression of the Phosphofructokinase and Glucokinase.

    Science.gov (United States)

    Gong, Yahui; Li, Tiyuan; Li, Shiyu; Jiang, Zhenyou; Yang, Yan; Huang, Junli; Liu, Zhaobing; Sun, Hanxiao

    2016-06-28

    Lactobacilli are universally recognized as probiotics that are widely used in the adjuvant treatment of inflammatory diseases, such as vaginitis and enteritis. With the overuse of antibiotics in recent years, the lactobacilli in the human body are killed, which could disrupt the microecological balance in the human body and affect health adversely. In this work, cephalosporin-resistant Lactobacillus casei RL20 was obtained successfully from the feces of healthy volunteers, which possessed a stable genetic set. However, the shortage of lactic acid (72.0 g/l at 48 h) by fermentation did not meet the requirement for its use in medicine. To increase the production of lactic acid, the functional genes pfk and glk were introduced into the wild strain. A yield of 144.2 g/l lactic acid was obtained in the transgenic L. casei RL20-2 after fermentation for 48 h in 1 L of basic fermentation medium with an initial glucose concentration of 100 g/l and increasing antibacterial activity. These data suggested that L. casei RL20-2 that exhibited a high yield of lactic acid may be a potential probiotic to inhibit the spread of bacterial infectious diseases and may be used for vaginitis therapy.

  1. High-yield fermentation and a novel heat-precipitation purification method for hydrophobin HGFI from Grifola frondosa in Pichia pastoris.

    Science.gov (United States)

    Song, Dongmin; Gao, Zhendong; Zhao, Liqiang; Wang, Xiangxiang; Xu, Haijin; Bai, Yanling; Zhang, Xiuming; Linder, Markus B; Feng, Hui; Qiao, Mingqiang

    2016-12-01

    Hydrophobins are proteins produced by filamentous fungi with high natural-surfactant activities and that can self-assemble in interfaces of air-water or solid-water to form amphiphilic membranes. Here, we reported a high-yield fermentation method for hydrophobin HGFI from Grifola frondosa in Pichia pastoris, attaining production of 300 mg/L by keeping the dissolved oxygen level at 15%-25% by turning the methanol-feeding speed. We also developed a novel HGFI-purification method enabling large-scare purification of HGFI, with >90% recovery. Additionally, we observed that hydrophobin HGFI in fermentation broth precipitated at pH 90 °C. We also identified the structure and properties of proteins purified by this method through atomic force microscopy, circular dichroism, X-ray photoelectron spectroscopy, and water-contact angle measurement, which is similar to protein purification by ultrafiltration without heating treatment that enables our method to maintain native HGFI structure and properties. Furthermore, the purification method presented here can be applied to large-scale purification of other type I hydrophobins. Copyright © 2016. Published by Elsevier Inc.

  2. High.yield cultivation technique for "Jingtian" No. 1 melon%景甜一号甜瓜高产高效栽培技术

    Institute of Scientific and Technical Information of China (English)

    朱团威

    2011-01-01

    Melon cultivation has a long history, but the problems of species simplification, extensive management, low yields, poor economic benefit, etc, are still existed. By means of introducing new varieties and assorted cultivation and management techniques to achieve high yield and high cost-effectiveness is an urgent need for melon production. A new varieties of sweet melon, "Jingtian" No. 1 melon, yields up to 3 000- 3 500kg per 667 m2, 1 000-1 500kg higher than the common varieties, has a good promotion prospect.%藤县种植甜瓜有悠久的历史,但存在品种单一,管理粗放,产量低,经济效益差等突出问题。引进甜瓜新品种及其配套栽培管理技术,达到高产高效是甜瓜生产的迫切需要。甜瓜新品种景甜一号采用科学的栽培管理技术进行栽培管理,可获得高产高效,每667m2产量达3 000~3 500kg,比一般品种每667m2增收1 000~1 500kg。

  3. An Efficient Synthesis Strategy for Metal-Organic Frameworks: Dry-Gel Synthesis of MOF-74 Framework with High Yield and Improved Performance.

    Science.gov (United States)

    Das, Atanu Kumar; Vemuri, Rama Sesha; Kutnyakov, Igor; McGrail, B Peter; Motkuri, Radha Kishan

    2016-06-16

    Vapor-assisted dry-gel synthesis of the metal-organic framework-74 (MOF-74) structure, specifically Ni-MOF-74 produced from synthetic precursors using an organic-water hybrid solvent system, showed a very high yield (>90% with respect to 2,5-dihydroxyterepthalic acid) and enhanced performance. The Ni-MOF-74 obtained showed improved sorption characteristics towards CO2 and the refrigerant fluorocarbon dichlorodifluoromethane. Unlike conventional synthesis, which takes 72 hours using the tetrahydrofuran-water system, this kinetic study showed that Ni-MOF-74 forms within 12 hours under dry-gel conditions with similar performance characteristics, and exhibits its best performance characteristics even after 24 hours of heating. In the dry-gel conversion method, the physical separation of the solvent and precursor mixture allows for recycling of the solvent. We demonstrated efficient solvent recycling (up to three times) that resulted in significant cost benefits. The scaled-up manufacturing cost of Ni-MOF-74 synthesized via our dry-gel method is 45% of conventional synthesis cost. Thus, for bulk production of the MOFs, the proposed vapor-assisted, dry-gel method is efficient, simple, and inexpensive when compared to the conventional synthesis method.

  4. A New, High Yield, Rapid, and Cost-Effective Protocol to Deprotection of Cysteine-Rich Conopeptide, Omega-Conotoxin MVIIA.

    Science.gov (United States)

    Eisapoor, Seyed Sahand; Jamili, Shahla; Shahbazzadeh, Delavar; Ghavam Mostafavi, Pargol; Pooshang Bagheri, Kamran

    2016-05-01

    Almost all conopeptides purified from Conus venoms are cysteine-rich peptides. Among them, omega-conotoxin MVIIA, FDA approved peptide drug (Prialt(®)), selected as a cysteine-rich model that its protection from oxidation is critical during solid phase synthesis. Deprotection of cysteines is a crucial step after peptide synthesis. The current study aimed to set up a new highly efficient deprotection protocol for omega-conotoxin MVIIA. Deprotection was performed based on mercury acetate with significant major modification. The protocol accomplished based on the best molar ratio of peptide/mercury/2-ME that adjusted to 0.2 mm/3 mm/10 mm (50 μg/1 mg/10 μL). The yield and purity of omega-conotoxin MVIIA obtained at 93 and 95%, respectively. The total time of protocol shortened to 90 min instead of 6-20 h in routine methods. In this study, omega-conotoxin MVIIA was recovered in high yield and in the shortest time. Despite of other known protocols, molar ratio adjusted to minimum amount. In conclusion, this protocol would be suggested to cost-effective deprotection of thiol groups for similar cysteine-rich peptides.

  5. High-yield preparation of wax esters via lipase-catalyzed esterification using fatty acids and alcohols from crambe and camelina oils.

    Science.gov (United States)

    Steinke, G; Weitkamp, P; Klein, E; Mukherjee, K D

    2001-02-01

    Fatty acids obtained from seed oils of crambe (Crambe abyssinica) and camelina (Camelina sativa) via alkaline saponification or steam splitting were esterified using lipases as biocatalysts with oleyl alcohol and the alcohols derived from crambe and camelina oils via hydrogenolysis of their methyl esters. Long-chain wax esters were thus obtained in high yields when Novozym 435 (immobilized lipase B from Candida antarctica) and papaya (Carica papaya) latex lipase were used as biocatalysts and vacuum was applied to remove the water formed. The highest conversions to wax esters were obtained with Novozym 435 (> or =95%) after 4-6 h of reaction, whereas with papaya latex lipase such a high degree of conversion was attained after 24 h. Products obtained from stoichiometric amounts of substrates were almost exclusively (>95%) composed of wax esters having compositions approaching that of jojoba (Simmondsia chinensis) oil, especially when crambe fatty acids in combination with camelina alcohols or camelina fatty acids in combination with crambe alcohols were used as substrates.

  6. 豌豆高产育种的选择指数分析%Selection Index of High Yield Breeding of Pea

    Institute of Scientific and Technical Information of China (English)

    杨如达; 杨林栋; 林凤仙; 贺维翔

    2011-01-01

    Grain weight per plant (Y) of pea has a close relationship with number of pods per plant ( X1 ), number of seeds per pod ( X2 ) and 100 seed weight ( X3 ). NCII genetic mating was used to analyze selection index of grain weight per plant in this study. The result showed that the selection index = 1. 1644X1 +0.3486X2 + 1. 6031X3 ,with the index efficiency of 0.84, which could be useful in high yield breeding of pea.%豌豆株粒重Y与株荚数X、荚粒数X、百粒重x遗传密切相关,本试验用NCⅡ遗传交配设计研究株粒重选择指数的数量关系.结果表明,选择指数I=1.1644X+0.3486X+1.6031X,指数效率为0.84,用该数量尺度指导豌豆高产育种准确有效.

  7. High-yielding cultivation techniques of ratooning rice in Changting county%长汀县再生稻丰产栽培技术

    Institute of Scientific and Technical Information of China (English)

    黄玉娥

    2011-01-01

    通过两年千亩再生稻示范,总结出一套再生稻丰产栽培技术。主要技术环节包括选用高产优质、再生力强品种;掌握播种期控制秧龄、适当早插;配方施肥、水分管理增强根系活力;合理留桩促进再生芽生长;及时防治病虫害。%Ratooning rice was planted in 66.7hm2 demonstration field in Changting for two years, a set of high-yielding cultivation techniques were summarized. The techniques included the selection of varieties with traits of high quality and strong regenerative ability, timely sowing and adjusting seedling age, appropriately early transplanting, fomula fertilization and water management to strengthen the vigor of root system, maintaining suitalbe stubble height for promoting the development of regenerated buds, disease and oest control.

  8. High-yielding Cultivation Technology of“Dafeng 30”Corn%玉米品种“大丰30”高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    张晓丽; 张薇; 李茂廷

    2014-01-01

    The "Dafeng 30" corn was a new variety bred by Shanxi Dafeng Seed Co. Ltd. and introduced by Ningxia Honghe Seed Co. Ltd. in 2009 for popularizing and planting in Ningxia and it was authorized by Ningxia Variety Approval Commit-tee in 2012. The high-yielding cultivation technology of "Dafeng 30" corn was introduced in aspects of site selection and soil preparation, fertilization, sowing, field management, pest and disease control, etc.%玉米品种“大丰30”是山西大丰种业有限公司培育的新品种,2009年由宁夏红河种子有限公司引进,在宁夏推广种植,2012年通过宁夏品种委员会审定。文章从选地与整地、施肥、播种、田间管理、病虫害防治等方面介绍了“大丰30”的高产栽培技术。

  9. High-Yield Soluble Expression and Simple Purification of the Antimicrobial Peptide OG2 Using the Intein System in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Yong-Gang Xie

    2013-01-01

    Full Text Available OG2 is a modified antimicrobial peptide, that is, derived from the frog peptide Palustrin-OG1. It has high antimicrobial activity and low cytotoxicity, and it is therefore promising as a therapeutic agent. Both prokaryotic (Escherichia coli and eukaryotic (Pichia pastoris production host systems were used to produce OG2 in our previous study; however, it was difficult to achieve high expression yields and efficient purification. In this study, we achieved high-yield OG2 expression using the intein fusion system. The optimized OG2 gene was cloned into the pTWIN1 vector to generate pTWIN-OG2-intein2 (C-terminal fusion vector and pTWIN-intein1-OG2 (N-terminal fusion vector. Nearly 70% of the expressed OG2-intein2 was soluble after the IPTG concentration and induction temperature were decreased, whereas only 42% of the expressed of intein1-OG2 was soluble. Up to 75 mg of OG2-intein2 was obtained from a 1 l culture, and 85% of the protein was cleaved by 100 mM DTT. Intein1-OG2 was less amenable to cleavage due to the inhibition of cleavage by the N-terminal amino acid of OG2. The purified OG2 exhibited strong antimicrobial activity against E. coli K88. The intein system is the best currently available system for the cost-effective production of OG2.

  10. Effect of Different Norms of Under-Mulch-Drip Irrigation on Diurnal Changes of Photosynthesis and Chlorophyll Fluorescence Parameter in High Yield Cotton of Xinjiang

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wang-feng; REN Li-tong; WANG Zhen-lin; LI Shao-kun; GOU Ling; YU Songlie; CAO Lian-pu

    2003-01-01

    Under-mulch-drip irrigation is an advanced irrigation technique, which combines plastic-film-covered cultivation with drip irrigation. The influence of different norms of under-mulch-drip irrigation on di-urnal changes of photosynthetic rates and chlorophyll fluorescence parameters of cotton was studied, in orderto understand the physiological mechanisms of water-saving and high-yielding farming in Xinjiang. Results in-dicated that limited drip irrigation, which supplies 2/3 of 375 m3 ha-1 , the widely-used irrigation norm in cot-ton cultivation in Xinjiang, caused a water deficit in cotton field. Compared with the proper drip irrigation,the leaf photosynthetic rate under limited drip irrigation decreased during 9:00 to 11:00 a. m., and was sig-nificantly suppressed at midday, and then recovered afterwards. Using the chlorophyll fluorescence method,the absorption, transfer and transformation features of solar radiation by cotton leaf were investigated. Underlimited drip irrigation, the variable fluorescence (Fy) and primary light transfer efficiency of PSII (Fv/Fm)in cotton leaves were reduced because of the high light intensities and high temperatures at noon, and the de-crease in Xinluzao8 was greater than that in Xinluzao6. Therefore, it could be concluded that Xinluzao6 has ahigher drought-tolerance, and the Fv/Fm ratio could be used as a drought-resistance index for cotton.

  11. Neutron generator for BNCT based on high current ECR ion source with gyrotron plasma heating.

    Science.gov (United States)

    Skalyga, V; Izotov, I; Golubev, S; Razin, S; Sidorov, A; Maslennikova, A; Volovecky, A; Kalvas, T; Koivisto, H; Tarvainen, O

    2015-12-01

    BNCT development nowadays is constrained by a progress in neutron sources design. Creation of a cheap and compact intense neutron source would significantly simplify trial treatments avoiding use of expensive and complicated nuclear reactors and accelerators. D-D or D-T neutron generator is one of alternative types of such sources for. A so-called high current quasi-gasdynamic ECR ion source with plasma heating by millimeter wave gyrotron radiation is suggested to be used in a scheme of D-D neutron generator in the present work. Ion source of that type was developed in the Institute of Applied Physics of Russian Academy of Sciences (Nizhny Novgorod, Russia). It can produce deuteron ion beams with current density up to 700-800 mA/cm(2). Generation of the neutron flux with density at the level of 7-8·10(10) s(-1) cm(-2) at the target surface could be obtained in case of TiD2 target bombardment with deuteron beam accelerated to 100 keV. Estimations show that it is enough for formation of epithermal neutron flux with density higher than 10(9) s(-1) cm(-2) suitable for BNCT. Important advantage of described approach is absence of Tritium in the scheme. First experiments performed in pulsed regime with 300 mA, 45 kV deuteron beam directed to D2O target demonstrated 10(9) s(-1) neutron flux. This value corresponds to theoretical estimations and proofs prospects of neutron generator development based on high current quasi-gasdynamic ECR ion source.

  12. Virtual neutron scattering experiments

    DEFF Research Database (Denmark)

    Overgaard, Julie Hougaard; Bruun, Jesper; May, Michael

    2017-01-01

    We describe how virtual experiments can be utilized in a learning design that prepares students for hands-on experiments at large-scale facilities. We illustrate the design by showing how virtual experiments are used at the Niels Bohr Institute in a master level course on neutron scattering....... In the last week of the course, students travel to a large-scale neutron scattering facility to perform real neutron scattering experiments. Through student interviews and survey answers, we argue, that the virtual training prepares the students to engage more fruitfully with experiments by letting them focus...... on physics and data rather than the overwhelming instrumentation. We argue that this is because they can transfer their virtual experimental experience to the real-life situation. However, we also find that learning is still situated in the sense that only knowledge of particular experiments is transferred...

  13. Virtual neutron scattering experiments

    DEFF Research Database (Denmark)

    Overgaard, Julie Hougaard; Bruun, Jesper; May, Michael

    2016-01-01

    We describe how virtual experiments can be utilized in a learning design that prepares students for hands-on experiments at large-scale facilities. We illustrate the design by showing how virtual experiments are used at the Niels Bohr Institute in a master level course on neutron scattering....... In the last week of the course, students travel to a large-scale neutron scattering facility to perform real neutron scattering experiments. Through student interviews and survey answers, we argue, that the virtual training prepares the students to engage more fruitfully with experiments by letting them focus...... on physics and data rather than the overwhelming instrumentation. We argue that this is because they can transfer their virtual experimental experience to the real-life situation. However, we also find that learning is still situated in the sense that only knowledge of particular experiments is transferred...

  14. Direction sensitive neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    Ahlen, Steven; Fisher, Peter; Dujmic, Denis; Wellenstein, Hermann F.; Inglis, Andrew

    2017-01-31

    A neutron detector includes a pressure vessel, an electrically conductive field cage assembly within the pressure vessel and an imaging subsystem. A pressurized gas mixture of CF.sub.4, .sup.3He and .sup.4He at respective partial pressures is used. The field cage establishes a relatively large drift region of low field strength, in which ionization electrons generated by neutron-He interactions are directed toward a substantially smaller amplification region of substantially higher field strength in which the ionization electrons undergo avalanche multiplication resulting in scintillation of the CF.sub.4 along scintillation tracks. The imaging system generates two-dimensional images of the scintillation patterns and employs track-finding to identify tracks and deduce the rate and direction of incident neutrons. One or more photo-multiplier tubes record the time-profile of the scintillation tracks permitting the determination of the third coordinate.

  15. Neutron absorbing alloy

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Masayuki

    1998-12-04

    The neutron absorbing alloy of the present invention comprises Ti or an alloy thereof as a mother material, to which from 2 to 40% by weight of Hf and Gd within a range of from 4 to 50% by weight in total are added respectively. Ti is excellent in specific strength, corrosion resistance and workability, and produces no noxious intermetallic compound with Hf and Gd. In addition, since the alloy can incorporate a great quantity of Hf and Gd, a neutron absorbing material having excellent neutron absorbing performance than usual and excellent in specific strength, corrosion resistance and workability can be manufactured conveniently and economically not by a special manufacturing method. (T.M.)

  16. Carbon neutron star atmospheres

    CERN Document Server

    Suleimanov, V F; Pavlov, G G; Werner, K

    2013-01-01

    The accuracy of measuring the basic parameters of neutron stars is limited in particular by uncertainties in chemical composition of their atmospheres. For example, atmospheres of thermally - emitting neutron stars in supernova remnants might have exotic chemical compositions, and for one of them, the neutron star in CasA, a pure carbon atmosphere has recently been suggested by Ho & Heinke (2009). To test such a composition for other similar sources, a publicly available detailed grid of carbon model atmosphere spectra is needed. We have computed such a grid using the standard LTE approximation and assuming that the magnetic field does not exceed 10^8 G. The opacities and pressure ionization effects are calculated using the Opacity Project approach. We describe the properties of our models and investigate the impact of the adopted assumptions and approximations on the emergent spectra.

  17. Uniformly rotating neutron stars

    CERN Document Server

    Boshkayev, Kuantay

    2016-01-01

    In this chapter we review the recent results on the equilibrium configurations of static and uniformly rotating neutron stars within the Hartle formalism. We start from the Einstein-Maxwell-Thomas-Fermi equations formulated and extended by Belvedere et al. (2012, 2014). We demonstrate how to conduct numerical integration of these equations for different central densities ${\\it \\rho}_c$ and angular velocities $\\Omega$ and compute the static $M^{stat}$ and rotating $M^{rot}$ masses, polar $R_p$ and equatorial $R_{\\rm eq}$ radii, eccentricity $\\epsilon$, moment of inertia $I$, angular momentum $J$, as well as the quadrupole moment $Q$ of the rotating configurations. In order to fulfill the stability criteria of rotating neutron stars we take into considerations the Keplerian mass-shedding limit and the axisymmetric secular instability. Furthermore, we construct the novel mass-radius relations, calculate the maximum mass and minimum rotation periods (maximum frequencies) of neutron stars. Eventually, we compare a...

  18. A preliminary study of a D-T tokamak fusion reactor with advanced blanket using compact fusion advanced Brayton (CFAB) cycle

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, K.; Ohnishi, M.; Yamamoto, Y. [Kyoto Univ. (Japan)] [and others

    1994-12-31

    Key issues on a D-T Tokamak fusion reactor with advanced blanket concept using CFAB (Compact Fusion Advanced Brayton) cycle are presented. Although the previously proposed and studied compact fusion advanced Rankine cycle using mercury liquid metal has shown, in general, excellent performance characteristics in extracting energy and electricity with high efficiency by the {open_quotes}in-situ{close_quotes} nonequilibrium MHD disk generator, and in enhancing safety potential, there was a fear about uses of hazardous mercury as primary coolant as well as its limited natural resources. To overcome these disadvantages while retaining the advantage features of a ultra-high temperature coolant inherent in the synchrotron energy-enhanced D-T tokamak reactor, a compact fusion advanced Brayton cycle using helium was reexamined which was once considered relatively not superior in the CFAR study, at the expense of high, but acceptable circulation power, lower heat transfer characteristics, and probably of a little bit reduced safety.

  19. Corrosion resistant neutron absorbing coatings

    Science.gov (United States)

    Choi, Jor-Shan [El Cerrito, CA; Farmer, Joseph C [Tracy, CA; Lee, Chuck K [Hayward, CA; Walker, Jeffrey [Gaithersburg, MD; Russell, Paige [Las Vegas, NV; Kirkwood, Jon [Saint Leonard, MD; Yang, Nancy [Lafayette, CA; Champagne, Victor [Oxford, PA

    2012-05-29

    A method of forming a corrosion resistant neutron absorbing coating comprising the steps of spray or deposition or sputtering or welding processing to form a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material. Also a corrosion resistant neutron absorbing coating comprising a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material.

  20. Atmospheres around Neutron Stars

    Science.gov (United States)

    Fryer, Chris L.; Benz, Willy

    1994-12-01

    Interest in the behavior of atmospheres around neutron stars has grown astronomically in the past few years. Some of this interest arrived in the wake of the explosion of Supernova 1987A and its elusive remnant; spawning renewed interest in a method to insure material ``fall-back'' onto the adolescent neutron star in an effort to transform it into a silent black hole. However, the bulk of the activity with atmospheres around neutron stars is concentrated in stellar models with neutron star, rather than white dwarf, cores; otherwise known as Thorne-Zytkow objects. First a mere seed in the imagination of theorists, Thorne-Zytkow objects have grown into an observational reality with an ever-increasing list of formation scenarios and observational prospects. Unfortunately, the analytic work of Chevalier on supernova fall-back implies that, except for a few cases, the stellar simulations of Thorne-Zytkow objects are missing an important aspect of physics: neutrinos. Neutrino cooling removes the pressure support of these atmospheres, allowing accretion beyond the canonical Eddington rate for these objects. We present here the results of detailed hydrodynamical simulations in one and two dimensions with the additional physical effects of neutrinos, advanced equations of state, and relativity over a range of parameters for our atmosphere including entropy and chemical composition as well as a range in the neutron star size. In agreement with Chevalier, we find, under the current list of formation scenarios, that the creature envisioned by Thorne and Zytkow will not survive the enormous appetite of a neutron star. However, neutrino heating (a physical effect not considered in Chevalier's analysis) can play an important role in creating instabilities in some formation schemes, leading to an expulsion of matter rather than rapid accretion. By placing scrutiny upon the formation methods, we can determine the observational prospects for each.

  1. Pixelated neutron image plates

    Science.gov (United States)

    Schlapp, M.; Conrad, H.; von Seggern, H.

    2004-09-01

    Neutron image plates (NIPs) have found widespread application as neutron detectors for single-crystal and powder diffraction, small-angle scattering and tomography. After neutron exposure, the image plate can be read out by scanning with a laser. Commercially available NIPs consist of a powder mixture of BaFBr : Eu2+ and Gd2O3 dispersed in a polymer matrix and supported by a flexible polymer sheet. Since BaFBr : Eu2+ is an excellent x-ray storage phosphor, these NIPs are particularly sensitive to ggr-radiation, which is always present as a background radiation in neutron experiments. In this work we present results on NIPs consisting of KCl : Eu2+ and LiF that were fabricated into ceramic image plates in which the alkali halides act as a self-supporting matrix without the necessity for using a polymeric binder. An advantage of this type of NIP is the significantly reduced ggr-sensitivity. However, the much lower neutron absorption cross section of LiF compared with Gd2O3 demands a thicker image plate for obtaining comparable neutron absorption. The greater thickness of the NIP inevitably leads to a loss in spatial resolution of the image plate. However, this reduction in resolution can be restricted by a novel image plate concept in which a ceramic structure with square cells (referred to as a 'honeycomb') is embedded in the NIP, resulting in a pixelated image plate. In such a NIP the read-out light is confined to the particular illuminated pixel, decoupling the spatial resolution from the optical properties of the image plate material and morphology. In this work, a comparison of experimentally determined and simulated spatial resolutions of pixelated and unstructured image plates for a fixed read-out laser intensity is presented, as well as simulations of the properties of these NIPs at higher laser powers.

  2. POLARIZED NEUTRONS IN RHIC

    Energy Technology Data Exchange (ETDEWEB)

    COURANT,E.D.

    1998-04-27

    There does not appear to be any obvious way to accelerate neutrons, polarized or otherwise, to high energies by themselves. To investigate the behavior of polarized neutrons the authors therefore have to obtain them by accelerating them as components of heavier nuclei, and then sorting out the contribution of the neutrons in the analysis of the reactions produced by the heavy ion beams. The best neutron carriers for this purpose are probably {sup 3}He nuclei and deuterons. A polarized deuteron is primarily a combination of a proton and a neutron with their spins pointing in the same direction; in the {sup 3}He nucleus the spins of the two protons are opposite and the net spin (and magnetic moment) is almost the same as that of a free neutron. Polarized ions other than protons may be accelerated, stored and collided in a ring such as RHIC provided the techniques proposed for polarized proton operation can be adapted (or replaced by other strategies) for these ions. To accelerate polarized particles in a ring, one must make provisions for overcoming the depolarizing resonances that occur at certain energies. These resonances arise when the spin tune (ratio of spin precession frequency to orbit frequency) resonates with a component present in the horizontal field. The horizontal field oscillates with the vertical motion of the particles (due to vertical focusing); its frequency spectrum is dominated by the vertical oscillation frequency and its modulation by the periodic structure of the accelerator ring. In addition, the magnet imperfections that distort the closed orbit vertically contain all integral Fourier harmonics of the orbit frequency.

  3. Spectroscopic factor strengths in $^{27}$Al(d,$^{3}$He)$^{26}$Mg and $^{27}$Al(d,$t$)$^{26}$Al reactions

    CERN Document Server

    Srivastava, P C

    2016-01-01

    In the present work we calculated spectroscopic factor strengths for recently measured experimental data for $1p$ and $1n$ pick-up reactions $^{27}$Al(d,$^{3}$He)$^{26}$Mg [Phys. Rev. C {\\bf 93}, 044601 (2016)] and $^{27}$Al( d,$t$)$^{26}$Al [Phys. Rev. C {\\bf 91}, 054611 (2015)] within the framework of the shell-model. We performed calculations with USDA and USDB effective interactions, results are in a good agreement with the experimental data.

  4. MONTE CARLO MODEL FOR NEUTRON PRODUCTION BY THE INTERACTIONS OF LOW ENERGY DEUTERONS IN SOLID TARGETS

    OpenAIRE

    Milocco, Alberto

    2012-01-01

    The construction of the nuclear fusion plant 'ITER' has started in 2009 at Cadarache, France. The ITER machine represents a milestone in the civil use of the nuclear fusion energy. The physics of ITER is based on the fusion reaction between deuteron and triton nuclei (d-t). The deuteron-deuteron reaction (d-d) is also interesting and is foreseen for the next generation of fusion reactors. The experimental activities carried out in the context of the ITER neutronics involve intense fields of n...

  5. Isotopic Abundances and Ratios in Arsenic Irradiated by High-Energy Neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Parker, W. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hall, J. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-06-07

    This document provides derivations of the 73As, 74As and 75As isotopic abundances and ratios in an arsenic sample irradiated by high-energy (14 MeV) neutrons for 0 ≤ t ≤ T, where T is short compared to the natural decay times of the reaction products (t1/2 (73As) ~ 80.3 d, t1/2 (74As) ~ 17.8 d). The document also outlines the historic approach used to analyze arsenic data from experiments.

  6. Neutronics optimization study for D-D fusion reactor blanket/shield

    Energy Technology Data Exchange (ETDEWEB)

    Shiba, T.; Kanda, Y.; Nakashima, H.

    1985-12-01

    Position-dependent optimization calculations have been carried out on a D-D fusion reactor blanket/shield to maximize the energy gain in the blanket and to minimize the atomic displacement rate of the copper stabilizer in the superconducting magnet. The results obtained by using the optimization code SWAN indicate the advantage of D/sub 2/O coolant over H/sub 2/O coolant with respect to increasing the energy gain, and the difference in the optimal shield distributions between D-T and D-D neutron sources. The possibility of improving both the energy gain and radiation shielding characteristics is also discussed.

  7. Hole states based on the {11}/{2}-[505] neutron orbital within the pairing gap

    Science.gov (United States)

    Peterson, R. J.; Garrett, J. D.

    1984-02-01

    Coupled-channel calculations have been performed for (d, p) and (d, t) reactions on the stable doubly even isotopes of Gd, Dy and Er for {11}/{2}- neutron transfer to the [505] band heads. Comparison to published data permitted reliable extraction of the occupation numbers for this orbital. The occupation numbers V2 were found to be much greater than the emptiness numbers U2, even for very low-lying excitations. These results can only be obtained for a very small pairing parameter, Δ, consistent with other less direct determinations. These results are as expected for a diminution of the pairing interaction for this oblate [505] orbital.

  8. New compact neutron polarizer

    Science.gov (United States)

    Krist, Th; Kennedy, S. J.; Hicks, T. J.; Mezei, F.

    A new type of a neutron polarizing bender was developed in co-operation with BENSC and ANSTO. It is based upon bent thin silicon wafers coated on one side with SiFeCo polarizing supermirrors and on the other side with Gd. Initial tests at BENSC in a 300 Oe magnetic field yielded a transmission of spin-up neutrons of about 55% over an angle range of 0.75° and flipping ratios > 30. Subsequent tests at ANSTO at 1200 Oe yielded a transmission of 48% with a flipping ratio > 45.

  9. FAST NEUTRONIC REACTOR

    Science.gov (United States)

    Snell, A.H.

    1957-12-01

    This patent relates to a reactor and process for carrying out a controlled fast neutron chain reaction. A cubical reactive mass, weighing at least 920 metric tons, of uranium metal containing predominantly U/sup 238/ and having a U/sup 235/ content of at least 7.63% is assembled and the maximum neutron reproduction ratio is limited to not substantially over 1.01 by insertion and removal of a varying amount of boron, the reactive mass being substantially freed of moderator.

  10. Helium 3 neutron precision polarimetry

    Science.gov (United States)

    Menard, Christopher

    2009-10-01

    Measuring neutron polarization to a high degree of precision is critical for the next generation of neutron decay correlation experiments. Polarized neutrons are also used in experiments to probe the hadronic weak interaction which contributes a small portion (˜10-7) of the force between nucleons. Using a beam of cold neutrons at Los Alamos Neutron Science Center (LANSCE), we polarized neutrons and measured their absolute polarization to ˜0.1%. Neutrons were polarized by passing them through a ^3He spin filter, relying on the maximally spin dependent 3He neutron absorption cross section. The neutron polarization can be determined by measuring the wavelength-dependent neutron transmission through the ^3He cell. An independent measurement of the neutron polarization was also obtained by passing the polarized beam through an RF spin flipper and a second polarized ^3He cell, used as an analyzer. To measure the efficiency of the spin flipper, the same measurements were made after reversing the ^3He polarization in the polarizer by using NMR techniques (adiabatic fast passage). We will show the consistency of these two measurements and the resulting precision of neutron polarimetry using these techniques.

  11. Keratinocyte Antiviral Response to Poly(dA:dT) Stimulation and Papillomavirus Infection in a Canine Model of X-Linked Severe Combined Immunodeficiency

    Science.gov (United States)

    Luff, Jennifer A.; Yuan, Hang; Kennedy, Douglas; Schlegel, Richard; Felsburg, Peter; Moore, Peter F.

    2014-01-01

    X-linked severe combined immunodeficiency (XSCID) is caused by a genetic mutation within the common gamma chain (γc), an essential component of the cytokine receptors for interleukin (IL)-2, IL-4, IL-7, IL-9, IL-15, and IL-21. XSCID patients are most commonly treated with bone marrow transplants (BMT) to restore systemic immune function. However, BMT-XSCID humans and dogs remain at an increased risk for development of cutaneous papillomavirus (PV) infections and their associated neoplasms, most typically cutaneous papillomas. Since basal keratinocytes are the target cell for the initial PV infection, we wanted to determine if canine XSCID keratinocytes have a diminished antiviral cytokine response to poly(dA:dT) and canine papillomavirus-2 (CPV-2) upon initial infection. We performed quantitative RT-PCR for antiviral cytokines and downstream interferon stimulated genes (ISG) on poly(dA:dT) stimulated and CPV-2 infected monolayer keratinocyte cultures derived from XSCID and normal control dogs. We found that XSCID keratinocytes responded similarly to poly(dA:dT) as normal keratinocytes by upregulating antiviral cytokines and ISGs. CPV-2 infection of both XSCID and normal keratinocytes did not result in upregulation of antiviral cytokines or ISGs at 2, 4, or 6 days post infection. These data suggest that the antiviral response to initial PV infection of basal keratinocytes is similar between XSCID and normal patients, and is not the likely source for the remaining immunodeficiency in XSCID patients. PMID:25025687

  12. Keratinocyte antiviral response to Poly(dA:dT stimulation and papillomavirus infection in a canine model of X-linked severe combined immunodeficiency.

    Directory of Open Access Journals (Sweden)

    Jennifer A Luff

    Full Text Available X-linked severe combined immunodeficiency (XSCID is caused by a genetic mutation within the common gamma chain (γc, an essential component of the cytokine receptors for interleukin (IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21. XSCID patients are most commonly treated with bone marrow transplants (BMT to restore systemic immune function. However, BMT-XSCID humans and dogs remain at an increased risk for development of cutaneous papillomavirus (PV infections and their associated neoplasms, most typically cutaneous papillomas. Since basal keratinocytes are the target cell for the initial PV infection, we wanted to determine if canine XSCID keratinocytes have a diminished antiviral cytokine response to poly(dA:dT and canine papillomavirus-2 (CPV-2 upon initial infection. We performed quantitative RT-PCR for antiviral cytokines and downstream interferon stimulated genes (ISG on poly(dA:dT stimulated and CPV-2 infected monolayer keratinocyte cultures derived from XSCID and normal control dogs. We found that XSCID keratinocytes responded similarly to poly(dA:dT as normal keratinocytes by upregulating antiviral cytokines and ISGs. CPV-2 infection of both XSCID and normal keratinocytes did not result in upregulation of antiviral cytokines or ISGs at 2, 4, or 6 days post infection. These data suggest that the antiviral response to initial PV infection of basal keratinocytes is similar between XSCID and normal patients, and is not the likely source for the remaining immunodeficiency in XSCID patients.

  13. Interferometric measurement of the temperature coefficient of the refractive index dn/dT and the coefficient of thermal expansion of Pr:YLF laser crystals.

    Science.gov (United States)

    Kazasidis, Orestis S; Wittrock, Ulrich

    2014-12-15

    We report interferometric measurements of the temperature coefficient of the refractive index (dn/dT) and the coefficient of thermal expansion (α) of a praseodymium-doped yttrium lithium fluoride (Pr:YLF) crystal and of a fused silica reference sample. Our phase-resolved interferometric method yields a large number of data points and thus allows a precise measurement and a good error estimation. Furthermore, both dn/dT and α are obtained simultaneously from a single measurement which reduces errors that can occur in separate measurements. Over the temperature range from 20 °C to 80 °C, the value of dn/dT of Pr:YLF decreases from −5.2 × 10(−6)/K to −6.2 × 10(−6)/K for the ordinary refractive index and from −7.6 × 10(−6)/K to −8.6 × 10(−6)/K for the extraordinary refractive index. The coefficient of thermal expansion for the a-axis of Pr:YLF increases from 16.4 × 10(−6)/K to 17.8 × 10(−6)/K over the same temperature range.

  14. Neutron storage time measurement for the neutron EDM experiment

    Science.gov (United States)

    Griffith, W. Clark; Ito, Takeyasu; Ramsey, John; Makela, Mark; Clayton, Steven; Hennings-Yeomans, Raul; Saidur Rahaman, M.; Currie, Scott; Womack, Todd; Sondheim, Walter; Cooper, Martin

    2010-11-01

    A new experiment to search for the neutron electric dipole moment (nEDM) is under development for installation at the Spallation Neutron Source (SNS) at Oakridge National Laboratory. The experiment will use ultra-cold neutrons (UCN) stored in superfluid helium, along with ^3He atoms acting as a neutron spin analyzer and comagnetometer. One crucial factor affecting the ultimate sensitivity of the experiment is the neutron storage time that can be obtained in the acrylic measurement cell. The acrylic cell walls will be coated with deuterated polystyrene (dPS), which is expected to give a wall loss factor of ˜room temperature and below 20 K.

  15. Neutron recognition in LAND detector for large neutron multiplicity

    CERN Document Server

    Pawłowski, P; Leifels, Y; Trautmann, W; Adrich, P; Aumann, T; Bacri, C O; Barczyk, T; Bassini, R; Bianchin, S; Boiano, C; Boretzky, K; Boudard, A; Chbihi, A; Cibor, J; Czech, B; De Napoli, M; Ducret, J -E; Emling, H; Frankland, J D; Gorbinet, T; Hellström, M; Henzlova, D; Hlavac, S; Immè, J; Iori, I; Johansson, H; Kezzar, K; Kupny, S; Lafriakh, A; Fèvre, A Le; Gentil, E Le; Leray, S; Łukasik, J; Lühning, J; Lynch, W G; Lynen, U; Majka, Z; Mocko, M; Müller, W F J; Mykulyak, A; Orth, H; Otte, A N; Palit, R; Panebianco, S; Pullia, A; Raciti, G; Rapisarda, E; Rossi, D; Salsac, M -D; Sann, H; Schwarz, C; Simon, H; Sfienti, C; Sümmerer, K; Tsang, M B; Verde, G; Veselsky, M; Volant, C; Wallace, M; Weick, H; Wiechula, J; Wieloch, A; Zwiegliński, B

    2012-01-01

    The performance of the LAND neutron detector is studied. Using an event-mixing technique based on one-neutron data obtained in the S107 experiment at the GSI laboratory, we test the efficiency of various analytic tools used to determine the multiplicity and kinematic properties of detected neutrons. A new algorithm developed recently for recognizing neutron showers from spectator decays in the ALADIN experiment S254 is described in detail. Its performance is assessed in comparison with other methods. The properties of the observed neutron events are used to estimate the detection efficiency of LAND in this experiment.

  16. Neutron beam imaging at neutron spectrometers at Dhruva

    Science.gov (United States)

    Desai, Shraddha S.; Rao, Mala N.

    2012-06-01

    A low efficiency, 2-Dimensional Position Sensitive Neutron Detector based on delay line position encoding is developed. It is designed to handle beam flux of 106-107 n/cm2/s and for monitoring intensity profiles of neutron beams. The present detector can be mounted in transmission mode, as the hardware allows maximum neutron transmission in sensitive region. Position resolution of 1.2 mm in X and Y directions, is obtained. Online monitoring of beam images and intensity profile of various neutron scattering spectrometers at Dhruva are presented. It shows better dynamic range of intensity over commercial neutron camera and is also time effective over the traditionally used photographic method.

  17. Cross sections for d-{sup 3}H neutron interactions with samarium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Junhua; He, Long [Hexi Univ., Zhangye (China). School of Physics and Electromechanical Engineering; Wu, Chunlei; Jiang, Li [Chinese Academy of Engineering Physics, Mianyang (China). Inst. of Nuclear Physics and Chemistry

    2016-11-01

    The cross sections for (n,x) reactions on samarium isotopes were measured at (d-T) neutron energies of 13.5 and 14.8 MeV with the activation technique. Samples were activated along with Nb and Al monitor foils to determine the incident neutron flux. Theoretical calculations of excitation functions were performed using the nuclear model codes TALYS-1.6 and EMPIRE-3.2 Malta with default parameters, at neutron energies varying from the reaction threshold to 20 MeV. The results were discussed and compared with experimental data found in the literature. At neutron energies 13.5 and 14.8 MeV, the cross sections of the {sup 149}Sm(n,p){sup 149}Pm reaction are reported for the first time. The cross sections of the {sup 150}Sm(n,p){sup 150}Pm, {sup 144}Sm(n,p){sup 144}Pm, {sup 152}Sm(n,α){sup 149}Nd and {sup 144}Sm(n,α){sup 141}Nd reactions at different neutron energies reported in the present work can be added as new data in the nuclear databases.

  18. Neutron Flux and Activation Calculations for a High Current Deuteron Accelerator

    CERN Document Server

    Coniglio, Angela; Sandri, Sandro

    2005-01-01

    Neutron analysis of the first Neutral Beam (NB) for the International Thermonuclear Experimental Reactor (ITER) was performed to provide the basis for the study of the following main aspects: personnel safety during normal operation and maintenance, radiation shielding design, transportability of the NB components in the European countries. The first ITER NB is a medium energy light particle accelerator. In the scenario considered for the calculation the accelerated particles are negative deuterium ions with maximum energy of 1 MeV. The average beam current is 13.3 A. To assess neutron transport in the ITER NB structure a mathematical model of the components geometry was implemented into MCNP computer code (MCNP version 4c2. "Monte Carlo N-Particle Transport Code System." RSICC Computer Code Collection. June 2001). The neutron source definition was outlined considering both D-D and D-T neutron production. FISPACT code (R.A. Forrest, FISPACT-2003. EURATOM/UKAEA Fusion, December 2002) was used to assess neutron...

  19. Measuring neutron yield and ρR anisotropies with activation foils at the National Ignition Facility

    Directory of Open Access Journals (Sweden)

    Bleuel D.L.

    2013-11-01

    Full Text Available Neutron yields at the National Ignition Facility (NIF are measured with a suite of diagnostics, including activation of ∼20–200 g samples of materials undergoing a variety of energy-dependent neutron reactions. Indium samples were mounted on the end of a Diagnostic Instrument Manipulator (DIM, 25–50 cm from the implosion, to measure 2.45 MeV D-D fusion neutron yield. The 336.2 keV gamma rays from the 4.5 hour isomer of 115mIn produced by (n,n′ reactions are counted in high-purity germanium detectors. For capsules producing D-T fusion reactions, zirconium and copper are activated via (n,2n reactions at various locations around the target chamber and bay, measuring the 14 MeV neutron yield to accuracies on order of 7%. By mounting zirconium samples on ports at nine locations around the NIF chamber, anisotropies in the primary neutron emission due to fuel areal density asymmetries can be measured to a relative precision of 3%.

  20. Characteristics of SiC neutron sensor spectrum unfolding process based on Bayesian inference

    Energy Technology Data Exchange (ETDEWEB)

    Cetnar, Jerzy; Krolikowski, Igor [Faculty of Energy and Fuels AGH - University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow (Poland); Ottaviani, L. [IM2NP, UMR CNRS 7334, Aix-Marseille University, Case 231 -13397 Marseille Cedex 20 (France); Lyoussi, A. [CEA, DEN, DER, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St-Paul-Lez-Durance (France)

    2015-07-01

    This paper deals with SiC detector signal interpretation in neutron radiation measurements in mixed neutron gamma radiation fields, which is called the detector inverse problem or the spectrum unfolding, and it aims in finding a representation of the primary radiation, based on the measured detector signals. In our novel methodology we resort to Bayesian inference approach. In the developed procedure the resultant spectra is unfolded form detector channels reading, where the estimated neutron fluence in a group structure is obtained with its statistical characteristic comprising of standard deviation and correlation matrix. In the paper we present results of unfolding process for case of D-T neutron source in neutron moderating environment. Discussions of statistical properties of obtained results are presented as well as of the physical meaning of obtained correlation matrix of estimated group fluence. The presented works has been carried out within the I-SMART project, which is part of the KIC InnoEnergy R and D program. (authors)

  1. Some Implications of Neutron Mirror Neutron Oscillation

    CERN Document Server

    Mohapatra, Rabindra N; Nussinov, S

    2005-01-01

    We comment on a recently discussed possibility of oscillations between neutrons and degenerate mirror neutrons in the context of mirror models for particles and forces. It has been noted by Bento and Berezhiani that if these oscillations occurred at a rate of $\\tau^{-1}_{NN'}\\sim sec^{-1}$, it would help explain putative super GKZ cosmic ray events provided the temperature of the mirror radiation is $\\sim 0.3-0.4$ times that of familiar cosmic microwave background radiation. We discuss how such oscillation time scales can be realized in mirror models and find that the simplest nonsupersymmetric model for this idea requires the existence of a low mass (30-3000 GeV) color triplet scalar or vector boson. A supersymmetric model, where this constraint can be avoided is severely constrained by the requirement of maintaining a cooler mirror sector. We also find that the reheat temperature after inflation in generic models that give fast $n-n'$ oscillation be less than about 100 GeV in order to maintain the required ...

  2. Neutron Scattering Investigations of Correlated Electron Systems and Neutron Instrumentation

    DEFF Research Database (Denmark)

    Holm, Sonja Lindahl

    are a unique probe for studying the atomic and molecular structure and dynamics of materials. Even though neutrons are very expensive to produce, the advantages neutrons provide overshadow the price. As neutrons interact weakly with materials compared to many other probes, e.g. electrons or photons......, it is possible to make a neutron scattering experiment through sample environment equipment like cryostats or pressure cells. Another advantage of neutron experiments is that the wavelength and energy of the neutron match the inter-atomic distances and basic excitations of solid materials. The scattering cross...... is not taken into account in previous reports on the field effect of magnetic scattering, since usually only L 0 is probed. A paper draft submitted for publication describing the results of elastic and inelastic neutron scattering experiments performed on the oxygen-doped La2CuO4+y HTSC is appended (Tc 40 K...

  3. Neutronic studies of the coupled moderators for spallation neutron sources

    Institute of Scientific and Technical Information of China (English)

    Yin Wen; Liang Jiu-Qing

    2005-01-01

    We investigate the neutronic performance of coupled moderators to be implemented in spallation neutron sources by Monte-Carlo simulation and give the slow neutron spectra for the cold and thermal moderators. CH4 moderator can provide slow neutrons with highly desirable characteristics and will be used in low-power spallation neutron soureces. The slow neutron intensity extracted from different angles has been calculated. The capability of moderation of liquid H2 is lower than H2O and liquid CH4 due to lower atomic number density of hydrogen but we can compensate for this disadvantage by using a premoderator. The H2O premoderator of 2cm thickness can reduce the heat deposition in the cold moderator by about 33% without spoiling the neutron pulse.

  4. Case History: Merging the Tools of DC Resistivity and Fracture Trace Analysis for Locating High Yield Domestic Water Wells in Karst Terrain, Shenandoah Valley, Virginia, USA

    Science.gov (United States)

    Frangos, W.; Eaton, L. S.

    2004-05-01

    The karstic eastern margin of Virginia's Shenandoah Valley hosts large volumes of high quality ground water in discrete zones or pockets. Industrial and culinary exploitation poses a challenging exploration problem. Recent work by the authors using geophysical and aerial photogrammetric techniques resulted in the successful location of three high- yield water wells. This indirect methodology increases the probability of locating valuable wells by locating geologic features that may harbor water-bearing zones. The eastern Shenandoah Valley is geologically complex. The underlying bedrock is dominantly limestones, dolomites, and shales of Cambrian age that have been extensively folded, fractured, and faulted. Geomorphologic features such as solution cavities, caves, disappearing streams, and sinkholes are common. Extensive alluvial fan and river terrace deposits, comprised dominantly of quartzite gravel and sand, cover much of the land surface, and fill surface depressions. The combination of sand and gravel filtering and large storage capacity in the voids makes this region ideal for producing a large quantity of high quality groundwater. Two sites were investigated for karst aquifers near the town of Stuarts Draft. Interbedded limestones and dolomites underlie Barth Farm, situated on the north bank of the South River. The owners attempted to installed a water well to service an active vineyard. The drilling located a previously unknown, water-filled cavern ~5 m below the surface; subsequent high pumping rates in finishing the well resulted in a surface collapse and the creation of a sinkhole. A second effort, offset by ~30 meters, resulted in a catastrophic collapse, and seriously endangered the lives of the drillers. A subsequent dipole-dipole DC resistivity survey delineated a conductive zone coincident with the two sinkholes. Fracture trace analysis of pre-drilling aerial photographs indicates the presence of lineaments that pass through this drilling site

  5. Helium production cross section Measurement of Pb and Sn for 14.9 MeV neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Takao, Yoshiyuki; Fujimoto, Toshihiro; Ozaki, Shuji; Muramasu, Masatomo; Nakashima, Hideki [Kyushu Univ., Fukuoka (Japan); Kanda, Yukinori; Ikeda, Yujiro

    1998-03-01

    Helium production cross sections of lead and tin for 14.9 MeV neutrons were measured by helium accumulation method. Lead and tin samples were irradiated with FNS, an intense d-T neutron source of JAERI. The amount of helium produced in the samples by the neutron irradiation was measured with the Helium Atoms Measurement System (HAMS) at Kyushu University. As the samples contained a small amount of helium because of their small helium production cross sections at 14.9 MeV, the samples were evaporated by radiation from a tungsten filament to decrease background gases at helium measurement. Uncertainties of the present results were less than {+-}4.4%. The results were compared with other experimental data in the literature and also compared with the evaluated values in JENDL-3.2. (author)

  6. High-Yield Expression of M2e Peptide of Avian Influenza Virus H5N1 in Transgenic Duckweed Plants.

    Science.gov (United States)

    Firsov, Aleksey; Tarasenko, Irina; Mitiouchkina, Tatiana; Ismailova, Natalya; Shaloiko, Lyubov; Vainstein, Alexander; Dolgov, Sergey

    2015-07-01

    Avian influenza is a major viral disease in poultry. Antigenic variation of this virus hinders vaccine development. However, the extracellular domain of the virus-encoded M2 protein (peptide M2e) is nearly invariant in all influenza A strains, enabling the development of a broad-range vaccine against them. Antigen expression in transgenic plants is becoming a popular alternative to classical expression methods. Here we expressed M2e from avian influenza virus A/chicken/Kurgan/5/2005(H5N1) in nuclear-transformed duckweed plants for further development of avian influenza vaccine. The N-terminal fragment of M2, including M2e, was selected for expression. The M2e DNA sequence fused in-frame to the 5' end of β-glucuronidase was cloned into pBI121 under the control of CaMV 35S promoter. The resulting plasmid was successfully used for duckweed transformation, and western analysis with anti-β-glucuronidase and anti-M2e antibodies confirmed accumulation of the target protein (M130) in 17 independent transgenic lines. Quantitative ELISA of crude protein extracts from these lines showed M130-β-glucuronidase accumulation ranging from 0.09-0.97 mg/g FW (0.12-1.96 % of total soluble protein), equivalent to yields of up to 40 μg M2e/g plant FW. This relatively high yield holds promise for the development of a duckweed-based expression system to produce an edible vaccine against avian influenza.

  7. Genome-Wide Identification of Differentially Expressed Genes Associated with the High Yielding of Oleoresin in Secondary Xylem of Masson Pine (Pinus massoniana Lamb by Transcriptomic Analysis.

    Directory of Open Access Journals (Sweden)

    Qinghua Liu

    Full Text Available Masson pine is an important timber and resource for oleoresin in South China. Increasing yield of oleoresin in stems can raise economic benefits and enhance the resistance to bark beetles. However, the genetic mechanisms for regulating the yield of oleoresin were still unknown. Here, high-throughput sequencing technology was used to investigate the transcriptome and compare the gene expression profiles of high and low oleoresin-yielding genotypes. A total of 40,690,540 reads were obtained and assembled into 137,499 transcripts from the secondary xylem tissues. We identified 84,842 candidate unigenes based on sequence annotation using various databases and 96 unigenes were candidates for terpenoid backbone biosynthesis in pine. By comparing the expression profiles of high and low oleoresin-yielding genotypes, 649 differentially expressed genes (DEGs were identified. GO enrichment analysis of DEGs revealed that multiple pathways were related to high yield of oleoresin. Nine candidate genes were validated by QPCR analysis. Among them, the candidate genes encoding geranylgeranyl diphosphate synthase (GGPS and (--alpha/beta-pinene synthase were up-regulated in the high oleoresin-yielding genotype, while tricyclene synthase revealed lower expression level, which was in good agreement with the GC/MS result. In addition, DEG encoding ABC transporters, pathogenesis-related proteins (PR5 and PR9, phosphomethylpyrimidine synthase, non-specific lipid-transfer protein-like protein and ethylene responsive transcription factors (ERFs were also confirmed to be critical for the biosynthesis of oleoresin. The next-generation sequencing strategy used in this study has proven to be a powerful means for analyzing transcriptome variation related to the yield of oleoresin in masson pine. The candidate genes encoding GGPS, (--alpha/beta-pinene, tricyclene synthase, ABC transporters, non-specific lipid-transfer protein-like protein, phosphomethylpyrimidine synthase

  8. High-yield Cultivation Techniques and Exploitation of Sweet Corn%甜玉米高产栽培技术和开发利用

    Institute of Scientific and Technical Information of China (English)

    尚赏; 郭书亚; 张艳; 汤其宁; 卢广远

    2014-01-01

    Sweet corn as a new vegetable and fruit food,already obtained the rapid development at home and abroad. The sweet corn had more polysaccharides,proteins and vitamins than normal corn contains,and had the good food taste,easy to digest and had high nutritional value. Sweet corn was developed using as the frozen food and processed into canned food,also as fresh corn for sale. Sweet corn had considerable economic benefits and wide market foreground. On the basis of quality traits and growth characteristics of sweet corn,and combined with the local production conditions,Systematically discussed and summarized the high yield cultivation techniques and the development and utilization of sweet corn.%由于甜玉米比普通玉米富含多糖、蛋白质及维生素,并且食用口感好、易于消化和营养价值极高,所以作为新兴蔬菜兼水果型食品,已经在国内外得到迅速发展。甜玉米的开发利用除作为速冻食品和加工成罐头食品外,也可以作为鲜食玉米出售。甜玉米具有较可观的经济效益和广阔的市场发展前景。该文介绍了甜玉米的品质性状、生育特点、高产栽培技术和开发利用。

  9. Net global warming potential and greenhouse gas intensity in rice agriculture driven by high yields and nitrogen use efficiency: a 5 year field study

    Science.gov (United States)

    Zhang, X.; Zhou, Z.; Liu, Y.; Xu, X.; Wang, J.; Zhang, H.; Xiong, Z.

    2015-11-01

    Our understanding of how net global warming potential (NGWP) and greenhouse gas intensity (GHGI) is affected by management practices aimed at food security with respect to rice agriculture remains limited. In the present study, a 5 year field experiment was conducted in China to evaluate the effects of integrated soil-crop system management (ISSM) on NGWP and GHGI after accounting for carbon dioxide (CO2) emissions from all sources (methane, CH4, and nitrous oxide, N2O, emissions, agrochemical inputs, Ei, and farm operations, Eo) and sinks (i.e., soil organic carbon, SOC, sequestration). For the improvement of rice yield and agronomic nitrogen use efficiency (NUE), four ISSM scenarios consisting of different nitrogen (N) fertilization rates relative to the local farmers' practice (FP) rate were carried out, namely, N1 (25 % reduction), N2 (10 % reduction), N3 (FP rate) and N4 (25 % increase). The results showed that compared with the FP, the four ISSM scenarios, i.e., N1, N2, N3 and N4, significantly increased the rice yields by 10, 16, 28 and 41 % and the agronomic NUE by 75, 67, 86 and 82 %, respectively. In addition, compared with the FP, the N1 and N2 scenarios significantly reduced the GHGI by 14 and 18 %, respectively, despite similar NGWPs. The N3 and N4 scenarios remarkably increased the NGWP and GHGI by an average of 67 and 36 %, respectively. In conclusion, the ISSM strategies are promising for both food security and environmental protection, and the ISSM scenario of N2 is the optimal strategy to realize high yields and high NUE together with low environmental impacts for this agricultural rice field.

  10. Screening and Breeding of a Strain for High Yield of Succinic Acid%一株丁二酸高产菌株的筛选与选育

    Institute of Scientific and Technical Information of China (English)

    王乐; 宇光海; 杨硕晔; 王为为; 惠明

    2015-01-01

    旨在提高丁二酸发酵生产水平,通过初筛、复筛从土壤中分离得到了高产丁二酸菌株,发酵结束后利用高效液相色谱法检测丁二酸的产率为34.45%。对菌株进行紫外诱变选育,结果表明,在底物葡萄糖的浓度为100 g/L时,丁二酸的产率提高了46%,达到了50.30%,残糖低于10 g/L。经形态学特征、生理生化指标测定以及16S rDNA序列分析等,鉴定该菌株为放线杆菌。%It was to improve the production of succinic acid. After the primary and secondary screening, a strain with high-yield of succinic acid was isolated from the soil. The succinic acid production of 34.45% was determined by the high performance liquid chromatography (HPLC)after the fermentation. Later, the UV mutagenic breeding of strains has been performed, resulting in the succinic acid production of 50.30% which increased by 46% in the substrate of glucose concentration of 100 g/L with the residual sugar lower than 10 g/L. After the determinations of morphological characteristics, physiological and biochemical index and 16S rDNA sequence analysis, the strain was identified asactinobacillus.

  11. Antiviral cationic peptides as a strategy for innovation in global health therapeutics for dengue virus: high yield production of the biologically active recombinant plectasin peptide.

    Science.gov (United States)

    Rothan, Hussin A; Mohamed, Zulqarnain; Suhaeb, Abdulrazzaq M; Rahman, Noorsaadah Abd; Yusof, Rohana

    2013-11-01

    Dengue virus infects millions of people worldwide, and there is no vaccine or anti-dengue therapeutic available. Antimicrobial peptides have been shown to possess effective antiviral activity against various viruses. One of the main limitations of developing these peptides as potent antiviral drugs is the high cost of production. In this study, high yield production of biologically active plectasin peptide was inexpensively achieved by producing tandem plectasin peptides as inclusion bodies in E. coli. Antiviral activity of the recombinant peptide towards dengue serotype-2 NS2B-NS3 protease (DENV2 NS2B-NS3pro) was assessed as a target to inhibit dengue virus replication in Vero cells. Single units of recombinant plectasin were collected after applying consecutive steps of refolding, cleaving by Factor Xa, and nickel column purification to obtain recombinant proteins of high purity. The maximal nontoxic dose (MNTD) of the recombinant peptide against Vero cells was 20 μM (100 μg/mL). The reaction velocity of DENV2 NS2B-NS3pro decreased significantly after increasing concentrations of recombinant plectasin were applied to the reaction mixture. Plectasin peptide noncompetitively inhibited DENV2 NS2B-NS3pro at Ki value of 5.03 ± 0.98 μM. The percentage of viral inhibition was more than 80% at the MNTD value of plectasin. In this study, biologically active recombinant plectasin which was able to inhibit dengue protease and viral replication in Vero cells was successfully produced in E. coli in a time- and cost- effective method. These findings are potentially important in the development of potent therapeutics against dengue infection.

  12. One-pot high-yield synthesis of single-crystalline gold nanorods using glycerol as a low-cost and eco-friendly reducing agent

    Science.gov (United States)

    Parveen, Rashida; Gomes, Janaina F.; Ullah, Sajjad; Acuña, José J. S.; Tremiliosi-Filho, Germano

    2015-10-01

    The formation of gold nanorods (AuNRs) has recently attracted great attention due to their shape-dependent optical properties that are important for many applications. The development of simpler and safer methods for the high-yield synthesis of AuNRs employing low-cost and easily handled reagents is thus of great importance. Here, we introduce, for the first time, a one-pot seedless method for the preparation of single-crystalline AuNRs in almost 100 % yield based on the use of glycerol in alkaline medium as an eco-friendly, low-cost and pH-tunable reducing agent. The synthesized AuNRs were characterized by UV-Vis-NIR spectroscopy, FEG-SEM and HRTEM. The effect of the presence of capping agent (CTAB) and the concentration of reactants (glycerol, NaOH and AgNO3) on the yield and aspect ratio (AR) of AuNRs is discussed. The AR and yield of AuNRs showed a clear dependence on the pH and temperature of the reaction mixture as well as on the concentration of AgNO3 added as an auxiliary reagent. The longitudinal plasmon resonance band of the resulting AuNRs can be tuned between 620 and 1200 nm by varying the reaction conditions. AuNRs with an aspect ratio (AR) of around 4 were obtained in almost 100 % yield at room temperature and under mild reducing environment. The formation of AuNRs is faster at higher pH (>11) and higher temperature (>30 °C), but the AuNR yield is smaller (fcc structure, free from structural faults or dislocations. The present green method, which introduces glycerol as a tunable reducing agent with a pH-dependent reducing power, can provide a more general strategy for the preparation of a wide range of metallic nanoparticles.

  13. Evaluation of capillary and myofiber density in the pectoralis major muscles of rapidly growing, high-yield broiler chickens during increased heat stress.

    Science.gov (United States)

    Joiner, K S; Hamlin, G A; Lien, A R J; Bilgili, S F

    2014-09-01

    Skeletal muscle development proceeds from early embryogenesis through marketing age in broiler chickens. While myofiber formation is essentially complete at hatching, myofiber hypertrophy can increase after hatch by assimilation of satellite cell nuclei into myofibers. As the diameter of the myofibers increases, capillary density peripheral to the myofiber is marginalized, limiting oxygen supply and subsequent diffusion into the myofiber, inducing microischemia. The superficial and deep pectoralis muscles constitute 25% of the total body weight in a market-age bird; thus compromise of those muscle groups can have profound economic impact on broiler production. We hypothesized that marginal capillary support relative to the hypertrophic myofibers increases the incidence of microischemia, especially in contemporary high-yield broilers under stressing conditions such as high environmental temperatures. We evaluated the following parameters in four different broiler strains at 39 and 53 days of age when reared under thermoneutral (20 to 25 C) versus hot (30 to 35 C) environmental conditions: capillary density, myofiber density and diameter, and degree of myodegeneration. Our data demonstrate that myofiber diameter significantly increased with age (P > or = 0.0001), while the absolute numbers of capillaries, blood vessels, and myofibers visible in five 400 x microscopic fields decreased (P > or = 0.0001). This is concomitant with marginalization of vascular support in rapidly growing myofibers. The myofiber diameter was significantly lower with hot environmental temperatures (P > or = 0.001); therefore, the absolute number of myofibers visible in five 400X microscopic fields was significantly higher. The incidence and subjective degree of myodegeneration characterized by loss of cross-striations, myocyte hyperrefractility, sarcoplasmic vacuolation, and nuclear pyknosis or loss also increased in hot conditions. Differences among strains were not observed.

  14. Nutrient Balance in Relation to High Yield and Good Quality of Potato on an Acid Purple Soil in Chongqing,China

    Institute of Scientific and Technical Information of China (English)

    HETIANXIU; HEFUJIAN; 等

    2001-01-01

    A field experiment was carried out to study nutrient balance among N,P,K and Mg in potato cultivation on an acid purple soil in Chongqing,China,The experiment included 8 treatments with equal P rate of 120 kg P2O5 hm-2 :N0K2,N1K2,NK2K2,N3K2,N2K0,N2K1,N2K1Mg and N2K3,where N0,N1,N2 and N3 stand for the N rates of 0,75,150 and 225 kg N hm-2 ,and K0,K1,K2 and K3 for the K rates of 0,165,330 and 495kg K2O hm-2,respectively,Among the treatments designed ,Treatment N2K2 with a nutrient suply ration of N:P2O5:K2O:MgO=1.25:1.275:0.28 gave the highest tuber yield nd dry matter ,highest starch and Zn and lowest NO3- contents in tuber,and high N,P and K use effciency with and uptake ratio of N:P:K:Mg=11.38:1:13.32:0.33 by tuber,Yield and starch and protein contents of tuber were the lowest in Treatment N0K2.Dry matter was the highest N,P and K utilization rates .Statistical analysis showed that yields of tuber and starch were in a positive linear correlation with the uptake amount of various nutrients and protein of the potato tuber was in a significantly positive linear correlation with tuber N content and in a singificantly negative linear correlation with tuber K and Mg contents .Balaced application of N,P,K and Mg fertilizers(Treatment N2K2)was recommended for realiztion of high yield and good quality in potato cultivation.

  15. Do the rich always become richer? Characterizing the leaf physiological response of the high-yielding rice cultivar Takanari to free-air CO2 enrichment.

    Science.gov (United States)

    Chen, Charles P; Sakai, Hidemitsu; Tokida, Takeshi; Usui, Yasuhiro; Nakamura, Hirofumi; Hasegawa, Toshihiro

    2014-02-01

    The development of crops which are well suited to growth under future environmental conditions such as higher atmospheric CO2 concentrations ([CO2]) is essential to meeting the challenge of ensuring food security in the face of the growing human population and changing climate. A high-yielding indica rice variety (Oryza sativa L. cv. Takanari) has been recently identified as a potential candidate for such breeding, due to its high productivity in present [CO2]. To test if it could further increase its productivity under elevated [CO2] (eCO2), Takanari was grown in the paddy field under season-long free-air CO2 enrichment (FACE, approximately 200 µmol mol(-1) above ambient [CO2]) and its leaf physiology was compared with the representative japonica variety 'Koshihikari'. Takanari showed consistently higher midday photosynthesis and stomatal conductance than Koshihikari under both ambient and FACE growth conditions over 2 years. Maximum ribulose-1,5-bisphosphate carboxylation and electron transport rates were higher for Takanari at the mid-grain filling stage in both years. Mesophyll conductance was higher in Takanari than in Koshihikari at the late grain-filling stage. In contrast to Koshihikari, Takanari grown under FACE conditions showed no decrease in total leaf nitrogen on an area basis relative to ambient-grown plants. Chl content was higher in Takanari than in Koshihikari at the same leaf nitrogen level. These results indicate that Takanari maintains its superiority over Koshihikari in regards to its leaf-level productivity when grown in elevated [CO2] and it may be a valuable resource for rice breeding programs which seek to increase crop productivity under current and future [CO2].

  16. In-Season Root-Zone Nitrogen Management Strategies for Improving Nitrogen Use Efficiency in High-Yielding Maize Production in China

    Institute of Scientific and Technical Information of China (English)

    MENG Qing-Feng; CHEN Xin-Ping; ZHANG Fu-Suo; CAO Ming-Hui; CUI Zhen-Ling; BAI Jin-Shun; YUE Shan-Chao; CHEN Su-Yi; T.M(U)LLER

    2012-01-01

    Many recently developed N management strategies have been extremely successful in improving N use efficiency.However,attempts to further increase grain yields have had limited success.Field experiments were conducted in 2007 and 2008 at four sites to evaluate the effect of an in-season root-zone N management strategy on maize (Zea mays L.).According to the in-season root-zone N management,the optimal N rate (ONR) was determined by subtracting measured soil mineral N (NH4+-N and NO3--N) in the root zone from N target values.Other treatments included a control without N fertilization,70% of ONR,130% of ONR,and recommended N rate (RNR) by agronomists in China that have been shown to approach maize yield potentials.Although apparent N recovery for the ONR treatment was significantly higher than that under RNR in 2007,grain yield declined from 13.3 to 11.0 Mg ha-1 because of an underestimation of N uptake.In 2008,N target values were adjusted to match crop uptake,and N fertilization rates were reduced from 450 kg N ha- 1 for RNR to 225 to 265 kg N ha-1 for ONR.High maize yields were maintained at 12.6 to 13.5 Mg ha-1,which were twice the yield from typical farmers'practice.As a result,apparent N recovery increased from 29% to 66%,and estimated N losses decreased significantly for the ONR treatment compared to the RNR treatment.In conclusion,the in-season root-zone N management approach was able to achieve high yields,high NUE and low N losses.

  17. A review on neutron reflectometry

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Soo; Lee, Chang Hee; Shim, Hae Seop; Seong, Baek Seok

    1999-03-01

    This report contains principle and characteristic of neutron reflectometry. Therefore, in case of operating neutron reflectometer at HANARO in future, it will be a reference to the user who wishes to use the instrument effectively. Also, the current situation of neutron reflectometer operating in the world was examined. The detail of neutron reflectometer such as GANS(MURR), ADAM(ILL), POSY II(ANL), ROG(IRI) was described. The recent research situation on neutron reflectometry was also examined and it helps us to determine research field. (author)

  18. Neutron proton crystallography station (PCS)

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, Zoe [Los Alamos National Laboratory; Kovalevsky, Andrey [Los Alamos National Laboratory; Johnson, Hannah [Los Alamos National Laboratory; Mustyakimov, Marat [Los Alamos National Laboratory

    2009-01-01

    The PCS (Protein Crystallography Station) at Los Alamos Neutron Science Center (LANSCE) is a unique facility in the USA that is designed and optimized for detecting and collecting neutron diffraction data from macromolecular crystals. PCS utilizes the 20 Hz spallation neutron source at LANSCE to enable time-of-flight measurements using 0.6-7.0 {angstrom} neutrons. This increases the neutron flux on the sample by using a wavelength range that is optimal for studying macromolecular crystal structures. The diagram below show a schematic of PCS and photos of the detector and instrument cave.

  19. Neutron detection efficiency determinations for the TUNL neutron-neutron and neutron-proton scattering-length measurements

    Energy Technology Data Exchange (ETDEWEB)

    Trotter, D.E. Gonzalez [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States)], E-mail: crowell@tunl.duke.edu; Meneses, F. Salinas [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Tornow, W. [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States)], E-mail: tornow@tunl.duke.edu; Crowell, A.S.; Howell, C.R. [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Schmidt, D. [Physikalisch-Technische Bundesanstalt, D-38116, Braunschweig (Germany); Walter, R.L. [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States)

    2009-02-11

    The methods employed and the results obtained from measurements and calculations of the detection efficiency for the neutron detectors used at Triangle Universities Nuclear Laboratory (TUNL) in the simultaneous determination of the {sup 1}S{sub 0} neutron-neutron and neutron-proton scattering lengths a{sub nn} and a{sub np}, respectively, are described. Typical values for the detector efficiency were 0.3. Very good agreement between the different experimental methods and between data and calculation has been obtained in the neutron energy range below E{sub n}=13MeV.

  20. Cooling of Neutron Stars

    Directory of Open Access Journals (Sweden)

    Grigorian H.

    2010-10-01

    Full Text Available We introduce the theoretical basis for modeling the cooling evolution of compact stars starting from Boltzmann equations in curved space-time. We open a discussion on observational verification of different neutron star models by consistent statistics. Particular interest has the question of existence of quark matter deep inside of compact object, which has to have a specific influence on the cooling history of the star. Besides of consideration of several constraints and features of cooling evolution, which are susceptible of being critical for internal structure of hot compact stars we have introduced a method of extraction of the mass distribution of the neutron stars from temperature and age data. The resulting mass distribution has been compared with the one suggested by supernove simulations. This method can be considered as an additional checking tool for the consistency of theoretical modeling of neutron stars. We conclude that the cooling data allowed existence of neutron stars with quark cores even with one-flavor quark matter.