WorldWideScience

Sample records for hamamatsu silicon pin

  1. Characterization and modeling of crosstalk and afterpulsing in Hamamatsu silicon photomultipliers

    International Nuclear Information System (INIS)

    Rosado, J.; Hidalgo, S.

    2015-01-01

    The crosstalk and afterpulsing in Hamamatsu silicon photomultipliers, called Multi-Pixel Photon Counters (MPPCs), have been studied in depth. Several components of the correlated noise have been identified according to their different possible causes and their effects on the signal. In particular, we have distinguished between prompt and delayed crosstalk as well as between trap-assisted and hole-induced afterpulsing. The prompt crosstalk has been characterized through the pulse amplitude spectrum measured at dark conditions. The newest MPPC series, which incorporate isolating trenches between pixels, exhibit a very low prompt crosstalk, but a small component remains likely due to secondary photons reflected on the top surface of the device and photon-generated minority carriers diffusing in the silicon substrate.We present a meticulous procedure to characterize the afterpulsing and delayed crosstalk through the amplitude and delay time distributions of secondary pulses. Our results indicate that both noise components are due to minority carriers diffusing in the substrate and that this effect is drastically reduced in the new MPPC series as a consequence of an increase of one order of magnitude in the doping density of the substrate.Finally, we have developed a Monte Carlo simulation to study the different components of the afterpulsing and crosstalk. The simulation results support our interpretation of the experimental data. They also demonstrate that trenches longer than those employed in the Hamamatsu MPPCs would reduce the crosstalk to a much greater extent

  2. Fast neutron damage of silicon pin photodiodes

    International Nuclear Information System (INIS)

    Dabrowski, W.; Korbel, K.; Skoczen, A.

    1990-01-01

    A Hamamatsu Photonics photodiode S1723 was tested with respect to the fast neutron radiation. The device was irradiated with neutrons of energies in the range of 0.5 MeV to 12 MeV from a Po-Be source. The irradiation was performed in several steps starting from the relatively low fluence of 2.5 x 10 10 n x cm -2 . The following characteristics were measured: leakage current vs bias voltage, capacitance vs bias voltage and vs frequency, noise vs time constant of a quasigaussian shaper and spectral density of noise. Significant changes of the leakage current and of the noise were observed at the fluence of neutrons as low as 2.5 x 10 10 n x cm -2 . 8 figs., 3 tabs., 15 refs. (author)

  3. A filter technique for optimising the photon energy response of a silicon pin diode dosemeter

    International Nuclear Information System (INIS)

    Olsher, R.H.; Eisen, Y.

    1996-01-01

    Unless they are energy compensated, silicon PIN diodes used in electronic pocket dosemeters, have significant over-response below 200 keV. Siemens is using three diodes in parallel with individual filters to produce excellent energy and angular response. An algorithm based on the photon spectrum of a single diode could be used to flatten the energy response. The commercial practice is to use a single diode with a simple filter to flatten the energy response, despite the mediocre low energy photon. The filter technique with an opening has been used for energy compensating GM detectors and proportional counters and a new variation of it has been investigated which compensates the energy response of a silicon PIN diode and maintains an extended low energy response. It uses a composite filter of two or more materials with several openings whose individual area is in the range of 15% to 25% of the diode's active area. One opening is centred over the diode's active area and others are located at the periphery of the active area to preserve a good polar response to ±45 o . Monte Carlo radiation transport methods were used to simulate the coupled electron-photon transport through a Hamamatsu S2506-01 diode and to determine the energy response of the diode for a variety of filters. In current mode, the resultant dosemeter energy response relative to air dose was within -15% and +30% for 0 o incidence over the energy range from 15 keV to 1 MeV. In pulse mode, the resultant dosemeter energy response was within -25% and +50% for 0 o incidence over the energy range from 30 keV to 10 MeV. For ±45 o incidence, the energy response was within -25% and +40% from 40 keV to 10 MeV. Theoretical viability of the filter technique has been shown in this work (Author)

  4. Silicide Schottky Contacts to Silicon: Screened Pinning at Defect Levels

    Energy Technology Data Exchange (ETDEWEB)

    Drummond, T.J.

    1999-03-11

    Silicide Schottky contacts can be as large as 0.955 eV (E{sub v} + 0.165 eV) on n-type silicon and as large as 1.05 eV (E{sub c} {minus} 0.07 eV) on p-type silicon. Current models of Schottky barrier formation do not provide a satisfactory explanation of occurrence of this wide variation. A model for understanding Schottky contacts via screened pinning at defect levels is presented. In the present paper it is shown that most transition metal silicides are pinned approximately 0.48 eV above the valence band by interstitial Si clusters. Rare earth disilicides pin close to the divacancy acceptor level 0.41 eV below the conduction band edge while high work function silicides of Ir and Pt pin close to the divacancy donor level 0.21 eV above the valence band edge. Selection of a particular defect pinning level depends strongly on the relative positions of the silicide work function and the defect energy level on an absolute energy scale.

  5. Testing of the KRI-developed Silicon PIN Radioxenon Detector

    International Nuclear Information System (INIS)

    Foxe, Michael P.; McIntyre, Justin I.

    2015-01-01

    Radioxenon detectors are used for the verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) in a network of detectors throughout the world called the International Monitoring System (IMS). The Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) Provisional Technical Secretariat (PTS) has tasked Pacific Northwest National Laboratory (PNNL) with testing a V.G. Khlopin Radium Institute (KRI) and Lares Ltd-developed Silicon PIN detector for radioxenon detection. PNNL measured radioxenon with the silicon PIN detector and determined its potential compared to current plastic scintillator beta cells. While the PNNL tested Si detector experienced noise issues, a second detector was tested in Russia at Lares Ltd, which did not exhibit the noise issues. Without the noise issues, the Si detector produces much better energy resolution and isomer peak separation than a conventional plastic scintillator cell used in the SAUNA systems in the IMS. Under the assumption of 1 cm 3 of Xe in laboratory-like conditions, 24-hr count time (12-hr count time for the SAUNA), with the respective shielding the minimum detectable concentrations for the Si detector tested by Lares Ltd (and a conventional SAUNA system) were calculated to be: 131m Xe - 0.12 mBq/m 3 (0.12 mBq/m 3 ); 133 Xe - 0.18 mBq/m 3 (0.21 mBq/m 3 ); 133m Xe - 0.07 mBq/m 3 (0.15 mBq/m 3 ); 135 Xe - 0.45 mBq/m 3 (0.67 mBq/m 3 ). Detection limits, which are one of the important factors in choosing the best detection technique for radioxenon in field conditions, are significantly better than for SAUNA-like detection systems for 131m Xe and 133m Xe, but similar for 133 Xe and 135 Xe. Another important factor is the amount of ''memory effect'' or carry over signal from one radioxenon measurement to the subsequent sample. The memory effect is reduced by a factor of 10 in the Si PIN detector compared to the current plastic scintillator cells. There is potential for further reduction with the

  6. The silicon-silicon oxide multilayers utilization as intrinsic layer on pin solar cells

    International Nuclear Information System (INIS)

    Colder, H.; Marie, P.; Gourbilleau, F.

    2008-01-01

    Silicon nanostructures are promising candidate for the intrinsic layer on pin solar cells. In this work we report on new material: silicon-rich silicon oxide (SRSO) deposited by reactive magnetron sputtering of a pure silica target and an interesting structure: multilayers consisting of a stack of SRSO and pure silicon oxide layers. Two thicknesses of the SRSO sublayer, t SRSO , are studied 3 nm and 5 nm whereas the thickness of silica sublayer is maintaining at 3 nm. The presence of nanocrystallites of silicon, evidenced by X-Ray diffraction (XRD), leads to photoluminescence (PL) emission at room temperature due to the quantum confinement of the carriers. The PL peak shifts from 1.3 eV to 1.5 eV is correlated to the decreasing of t SRSO from 5 nm down to 3 nm. In the purpose of their potential utilization for i-layer, the optical properties are studied by absorption spectroscopy. The achievement a such structures at promising absorption properties. Moreover by favouring the carriers injection by the tunnel effect between silicon nanograins and silica sublayers, the multilayers seem to be interesting for solar cells

  7. Continuous Holdup Measurements with Silicon P-I-N Photodiodes

    International Nuclear Information System (INIS)

    Bell, Z.W.; Oberer, R.B.; Williams, J.A.; Smith, D.E.; Paulus, M.J.

    2002-01-01

    We report on the behavior of silicon P-I-N photodiodes used to perform holdup measurements on plumbing. These detectors differ from traditional scintillation detectors in that no high-voltage is required, no scintillator is used (gamma and X rays are converted directly by the diode), and they are considerably more compact. Although the small size of the diodes means they are not nearly as efficient as scintillation detectors, the diodes' size does mean that a detector module, including one or more diodes, pulse shaping electronics, analog-to-digital converter, embedded microprocessor, and digital interface can be realized in a package (excluding shielding) the size of a pocket calculator. This small size, coupled with only low-voltage power requirement, completely solid-state realization, and internal control functions allows these detectors to be strategically deployed on a permanent basis, thereby reducing or eliminating the need for manual holdup measurements. In this paper, we report on the measurement of gamma and X rays from 235 U and 238 U contained in steel pipe. We describe the features of the spectra, the electronics of the device and show how a network of them may be used to improve estimates of inventory in holdup

  8. Advances in the project about Pin type silicon radiation detectors

    International Nuclear Information System (INIS)

    Ramirez F, J.; Cerdeira, A.; Aceves, M.; Diaz, A.; Estrada, M.; Rosales, P.; Cabal, A.E.; Montano L, M.; Leyva, A.

    1998-01-01

    The obtained advances in the collaboration project ININ-CINVESTAV about development of Pin type semiconductor radiation detectors here are presented. It has been characterized the response to different types of radiation made in CINVESTAV and INAOE. Measurements have been realized with different types of sensitive to charge preamplifiers determining the main characteristics which must be executed to be able to be employed with low capacitance detectors. As applications it has been possible to measure the irradiation time in a mammography machine and X-ray energy spectra have been obtained in the order of 14 KeV, with 4 KeV at ambient temperature. The future actions of project have been indicated and the possible applications of these detectors. (Author)

  9. Silicon P.I.N. Junctions used for studies of radiation damage

    International Nuclear Information System (INIS)

    Lanore, J.

    1964-06-01

    Irradiation of silicon P.I.N. junction has been studied primarily for the purpose of developing a radiation damage dosimeter, but also for the purpose of investigating silicon itself. It is known that the rate of recombination of electrons and holes is a linear function of defects introduced by neutron irradiation. Two methods have been used to measure that rate of recombination: forward characteristic measurements, recovery time measurements. In order to explain how these two parameters depend on recombination rate we have given a theory of the P.I.N. junction. We have also given an idea of the carrier lifetime dependence versus temperature. Annealing effects in the range of 70 to 700 K have also been studied, we found five annealing stages with corresponding activation energies. As an application for these studies, we developed a radiation damage dosimeter with which we made several experiments in facilities such as Naiade or Marias. (author) [fr

  10. Comparison of silicon pin diode detector fabrication processes using ion implantation and thermal doping

    International Nuclear Information System (INIS)

    Zhou, C.Z.; Warburton, W.K.

    1996-01-01

    Two processes for the fabrication of silicon p-i-n diode radiation detectors are described and compared. Both processes are compatible with conventional integrated-circuit fabrication techniques and yield very low leakage currents. Devices made from the process using boron thermal doping have about a factor of 2 lower leakage current than those using boron ion implantation. However, the boron thermal doping process requires additional process steps to remove boron skins. (orig.)

  11. An improved PIN photodetector with integrated JFET on high-resistivity silicon

    International Nuclear Information System (INIS)

    Dalla Betta, Gian-Franco; Piemonte, Claudio; Boscardin, Maurizio; Gregori, Paolo; Zorzi, Nicola; Fazzi, Alberto; Pignatel, Giorgio U.

    2006-01-01

    We report on a PIN photodetector integrated with a Junction Field Effect Transistor (JFET) on a high-resistivity silicon substrate. Owing to a modified fabrication technology, the electrical and noise characteristics of the JFET transistor have been enhanced with respect to the previous versions of the device, allowing the performance to be significantly improved. In this paper, the main design and technological aspects relevant to the proposed structure are addressed and experimental results from the electrical characterization are discussed

  12. Comparison of proton microbeam and gamma irradiation for the radiation hardness testing of silicon PIN diodes

    Science.gov (United States)

    Jakšić, M.; Grilj, V.; Skukan, N.; Majer, M.; Jung, H. K.; Kim, J. Y.; Lee, N. H.

    2013-09-01

    Simple and cost-effective solutions using Si PIN diodes as detectors are presently utilized in various radiation-related applications in which excessive exposure to radiation degrades their charge transport properties. One of the conventional methods for the radiation hardness testing of such devices is time-consuming irradiation with electron beam or gamma-ray irradiation facilities, high-energy proton accelerators, or with neutrons from research reactors. Recently, for the purpose of radiation hardness testing, a much faster nuclear microprobe based approach utilizing proton irradiation has been developed. To compare the two different irradiation techniques, silicon PIN diodes have been irradiated with a Co-60 gamma radiation source and with a 6 MeV proton microbeam. The signal degradation in the silicon PIN diodes for both irradiation conditions has been probed by the IBIC (ion beam induced charge) technique, which can precisely monitor changes in charge collection efficiency. The results presented are reviewed on the basis of displacement damage calculations and NIEL (non-ionizing energy loss) concept.

  13. Effect of swift heavy Kr ions on complex permittivity of silicon PIN diode

    International Nuclear Information System (INIS)

    Li, Yun; Su, Ping; Yang, Zhimei; Ma, Yao; Gong, Min

    2016-01-01

    Highlights: • The complex permittivity has been studied on Si PIN irradiated by heavy Kr ions. • DLTS was used to investigate damages formed in PIN diode during irradiation. • The recombination of carriers has important influence on the complex permittivity. - Abstract: The complex permittivity has been researched on silicon PIN diodes irradiated by 2150 MeV heavy Kr ions in this article. The difference of complex permittivity spectra from 1 to 10^7 Hz between irradiated and unirradiated were observed and discussed. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics were measured at room temperature (300 K) to study the change of electrical properties in diode after irradiation. Deep level transient spectroscopy (DLTS) was used to investigate damages caused by 2150 MeV heavy Kr ions in diode. Two extra electron traps were observed, which were located at E C -0.31 eV and E C -0.17 eV. It indicated that new defects have been formed in PIN diode during irradiation. A comparison of the results illustrated that not only the carrier density but also the recombination of electron-hole pair have important influences on the properties of complex permittivity. These results offer a further indication of the mechanism about the complex permittivity property of semiconductor device, which could help to make the applications for the semiconductor device controlled by electric signals come true in the fields of optoelectronic integrated circuits, plasma antenna and so on.

  14. Leakage current of amorphous silicon p-i-n diodes made by ion shower doping

    International Nuclear Information System (INIS)

    Kim, Hee Joon; Cho, Gyuseong; Choi, Joonhoo; Jung, Kwan-Wook

    2002-01-01

    In this letter, we report the leakage current of amorphous silicon (a-Si:H) p-i-n photodiodes, of which the p layer is formed by ion shower doping. The ion shower doping technique has an advantage over plasma-enhanced chemical vapor deposition (PECVD) in the fabrication of a large-area amorphous silicon flat-panel detector. The leakage current of the ion shower diodes shows a better uniformity within a 30 cmx40 cm substrate than that of the PECVD diodes. However, it shows a higher leakage current of 2-3 pA/mm 2 at -5 V. This high current originates from the high injection current at the p-i junction

  15. Temperature dependence of the radiation induced change of depletion voltage in silicon PIN detectors

    International Nuclear Information System (INIS)

    Ziock, H.J.; Holzscheiter, K.; Morgan, A.; Palounek, A.P.T.; Ellison, J.; Heinson, A.P.; Mason, M.; Wimpenny, S.J.; Barberis, E.; Cartiglia, N.; Grillo, A.; O'Shaughnessy, K.; Rahn, J.; Rinaldi, P.; Rowe, W.A.; Sadrozinski, H.F.W.; Seiden, A.; Spencer, E.; Webster, A.; Wichmann, R.; Wilder, M.; Coupal, D.; Pal, T.

    1993-01-01

    The silicon microstrip detectors that will be used in the SDC experiment at the Superconducting Super Collider (SSC) will be exposed to very large fluences of charged particles, neutrons, and gammas. The authors present a study of how temperature affects the change in the depletion voltage of silicon PIN detectors damaged by radiation. They study the initial radiation damage and the short-term and long-term annealing of that damage as a function of temperature in the range from -10 degrees C to +50 degrees C, and as a function of 800 MeV proton fluence up to 1.5 x 10 14 p/cm 2 . They express the pronounced temperature dependencies in a simple model in terms of two annealing time constants which depend exponentially on the temperature

  16. Effect of swift heavy Kr ions on complex permittivity of silicon PIN diode

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yun [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China); Su, Ping, E-mail: pingsu@scu.edu.cn [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Key Lab of Microelectronics Sichuan Province, Sichuan University, Chengdu, Sichuan 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China); Yang, Zhimei; Ma, Yao [Key Lab of Microelectronics Sichuan Province, Sichuan University, Chengdu, Sichuan 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China); Gong, Min, E-mail: mgong@scu.edu.cn [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Key Lab of Microelectronics Sichuan Province, Sichuan University, Chengdu, Sichuan 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China)

    2016-12-01

    Highlights: • The complex permittivity has been studied on Si PIN irradiated by heavy Kr ions. • DLTS was used to investigate damages formed in PIN diode during irradiation. • The recombination of carriers has important influence on the complex permittivity. - Abstract: The complex permittivity has been researched on silicon PIN diodes irradiated by 2150 MeV heavy Kr ions in this article. The difference of complex permittivity spectra from 1 to 10^7 Hz between irradiated and unirradiated were observed and discussed. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics were measured at room temperature (300 K) to study the change of electrical properties in diode after irradiation. Deep level transient spectroscopy (DLTS) was used to investigate damages caused by 2150 MeV heavy Kr ions in diode. Two extra electron traps were observed, which were located at E{sub C}-0.31 eV and E{sub C}-0.17 eV. It indicated that new defects have been formed in PIN diode during irradiation. A comparison of the results illustrated that not only the carrier density but also the recombination of electron-hole pair have important influences on the properties of complex permittivity. These results offer a further indication of the mechanism about the complex permittivity property of semiconductor device, which could help to make the applications for the semiconductor device controlled by electric signals come true in the fields of optoelectronic integrated circuits, plasma antenna and so on.

  17. Integrated Amorphous Silicon p-i-n Temperature Sensor for CMOS Photonics

    Directory of Open Access Journals (Sweden)

    Sandro Rao

    2016-01-01

    Full Text Available Hydrogenated amorphous silicon (a-Si:H shows interesting optoelectronic and technological properties that make it suitable for the fabrication of passive and active micro-photonic devices, compatible moreover with standard microelectronic devices on a microchip. A temperature sensor based on a hydrogenated amorphous silicon p-i-n diode integrated in an optical waveguide for silicon photonics applications is presented here. The linear dependence of the voltage drop across the forward-biased diode on temperature, in a range from 30 °C up to 170 °C, has been used for thermal sensing. A high sensitivity of 11.9 mV/°C in the bias current range of 34–40 nA has been measured. The proposed device is particularly suitable for the continuous temperature monitoring of CMOS-compatible photonic integrated circuits, where the behavior of the on-chip active and passive devices are strongly dependent on their operating temperature.

  18. Silicon Waveguide with Lateral p-i-n Diode for Nonlinearity Compensation by On-Chip Optical Phase Conjugation

    DEFF Research Database (Denmark)

    Gajda, A.; Da Ros, Francesco; Porto da Silva, Edson

    2018-01-01

    A 1-dB Q-factor improvement through optical phase conjugation in a silicon waveguide with a lateral p-i-n diode enables BER

  19. High-speed and efficient silicon modulator based on forward-biased pin diodes

    Directory of Open Access Journals (Sweden)

    Suguru eAkiyama

    2014-11-01

    Full Text Available Silicon modulators, which use the free-carrier-plasma effect, were studied, both analytically and experimentally. It was demonstrated that the loss-efficiency product, a-VpL, was a suitable figure of merit for silicon modulators that enabled their intrinsic properties to be compared. Subsequently, the dependence of VpL on frequency was expressed by using the electrical parameters of a phase shifter when the modulator was operated by assuming a simple driving configuration. A diode-based modulator operated in forward biased mode was expected from analyses to provide more efficient operation than that in reversed mode at high frequencies due to its large capacitance. We obtained an a-VpL of 9.5 dB-V at 12.5 GHz in experiments by using the fabricated phase shifter with pin diodes operated in forward biased mode. This a-VpL was comparable to the best modulators operated in depletion mode. The modulator exhibited a clear eye opening at 56 Gb/s operated by 2 V peak-to-peak signals that was achieved by incorporating such a phase shifter into a ring resonator.

  20. Characterization of Lateral Structure of the p-i-n Diode for Thin-Film Silicon Solar Cell.

    Science.gov (United States)

    Kiaee, Zohreh; Joo, Seung Ki

    2018-03-01

    The lateral structure of the p-i-n diode was characterized for thin-film silicon solar cell application. The structure can benefit from a wide intrinsic layer, which can improve efficiency without increasing cell thickness. Compared with conventional thin-film p-i-n cells, the p-i-n diode lateral structure exploited direct light irradiation on the absorber layer, one-side contact, and bifacial irradiation. Considering the effect of different carrier lifetimes and recombinations, we calculated efficiency parameters by using a commercially available simulation program as a function of intrinsic layer width, as well as the distance between p/i or n/i junctions to contacts. We then obtained excellent parameter values of 706.52 mV open-circuit voltage, 24.16 mA/Cm2 short-circuit current, 82.66% fill factor, and 14.11% efficiency from a lateral cell (thickness = 3 μm; intrinsic layer width = 53 μm) in monofacial irradiation mode (i.e., only sunlight from the front side was considered). Simulation results of the cell without using rear-side reflector in bifacial irradiation mode showed 11.26% front and 9.72% rear efficiencies. Our findings confirmed that the laterally structured p-i-n cell can be a potentially powerful means for producing highly efficient, thin-film silicon solar cells.

  1. The measurement of phi 60 mm x 600 mu m silicon PIN detector gamma sensitivity and time respond

    CERN Document Server

    Hu Meng Chun; Ye Wen Ying

    2002-01-01

    phi 60 mm x 600 mu m silicon PIN detector is a large area and high sensitive one which has been developed in near years. The authors have measured their gamma sensitivity and the time response. The experiment and theoretical calculated results in: sup 6 sup 0 Co gamma sensitivity is about 5 fC centre dot cm sup 2 /MeV, the rise time is about 10 ns and the half-high-width time is about 35 ns

  2. Prediction of the Response of the Commercial BPW34FS Silicon p-i-n Diode Used as Radiation Monitoring Sensors up to Very High Fluences

    CERN Document Server

    Mekki, J; Glaser, M; Moll, M; Dusseau, L

    2010-01-01

    The effect of radiation damage on Silicon p-i-n diodes has been studied. I-V characteristics of BPW34FS silicon p-i-n diodes irradiated with 24 GeV/c protons up to 6.3 x 10(15) n(eq)/cm(2) have been measured and analyzed. A parameterization predicting the radiation response in the fluence range relevant for the use of the diodes as radiation monitors in Super-LHC experiments is presented.

  3. Conception and modelling of photo-detection pixels. PIN photodiodes conceived in amorphous silicon for particles detection

    International Nuclear Information System (INIS)

    Negru, R.

    2008-06-01

    The research done has revealed that the a-Si:H is a material ideally suited for the detection of particles, while being resistant to radiation. It also has a low manufacturing cost, is compatible with existing technology and can be deposited over large areas. Thus, despite the low local mobility of charges (30 cm 2 /V/s), a-Si:H is a material of particular interest for manufacturing high-energy particle detection pixels. As a consequence of this, we have studied the feasibility of an experimental pixel stacked structure based on a-Si:H as a basic sensor element for an electromagnetic calorimeter. The structure of such a pixel consists of different components. First, a silicon PIN diode in a-Si:H is fabricated, followed by a bias resistor and a decoupling capacitor. Before such a structure is made and in order to optimize its design, it is essential to have an efficient behavioural model of the various components. Thus, our primary goal was to develop a two-dimensional physical model of the PIN diode using the SILVACO finite element calculation software. This a-Si:H PIN diode two-dimensional physical model allowed us to study the problem of crosstalk between pixels in a matrix structure of detectors. In particular, we concentrated on the leakage current and the current generated in the volume between neighbouring pixels. The successful implementation of this model in SPICE ensures its usefulness in other professional simulators and especially its integration into a complete electronic structure (PIN diode, bias resistor, decoupling capacity and low noise amplifier). Thanks to these modelling tools, we were able to simulate PIN diode structures in a-Si:H with different thicknesses and different dimensions. These simulations have allowed us to predict that the thicker structures are relevant to the design of the pixel detectors for high energy physics. Applications in astronomy, medical imaging and the analysis of the failure of silicon integrated circuits, can also

  4. Luminescence in amorphous silicon p-i-n diodes under double-injection dispersive-transport-controlled recombination

    International Nuclear Information System (INIS)

    Han, D.; Wang, K.; Yeh, C.; Yang, L.; Deng, X.; Von Roedern, B.

    1997-01-01

    The temperature and electric-field dependence of the forward bias current and the electroluminescence (EL) in hydrogenated amorphous silicon (a-Si:H) p-i-n and n-i-p diodes have been studied. Both the current and the EL efficiency temperature dependence show three regions depending on either hopping-controlled or multiple-trapping or ballistic transport mechanisms. Comparing the thermalization-controlled geminate recombination processes of photoluminescence to the features of EL, the differences can be explained by transport-controlled nongeminate recombination in trap-rich materials. copyright 1997 The American Physical Society

  5. Commissioning of the new GMOS-N Hamamatsu CCDs

    Science.gov (United States)

    Scharwaechter, Julia; Chiboucas, Kristin; Gimeno, German; Boucher, Luc; White, John; Tapia, Eduardo; Lundquist, Michael; Rippa, Mathew; Labrie, Kathleen; Murowinski, Richard; Lazo, Manuel; Miller, Jennifer

    2017-06-01

    We report on the commissioning of the new Hamamatsu fully-depleted CCDs for GMOS-N, installed in the instrument in February 2017. The Hamamatsu detectors replace the e2v deep depletion devices which had been in operation since 2011. The new GMOS-N detector array is expected to provide improved red sensitivity compared to the e2v devices at wavelengths longer than ~900 nm. The commissioning of the new detector array for GMOS-N marks the final step in upgrading the two GMOS instruments at Gemini North and South with Hamamatsu detectors.

  6. Method of producing p-i-n structures by compensation of lithium ions from both side of silicon

    International Nuclear Information System (INIS)

    Muminov, R.A.; Radjapov, S.A.; Saymbetov, A.K.; Tursunkulov, O.M.; Pindurin, Yu.S.

    2007-01-01

    Full text: Semiconductor nuclear radiation detectors are needed to solve certain problems in nuclear spectroscopy. The development of efficiency detectors became possible with advances in growing high purify silicon single crystals with the required properties, satisfying the requirements for obtaining detectors based on them. One important requirement for obtaining detectors with sensitive area is that its resistance must be high. This is achieved by using the lithium ion drift process in the volume of the semiconductor detector. Thus it has been developed and created silicon semiconductor nuclear radiation detectors with vide range of diameter of sensitive area up to 100 mm and thickness (from 1mm to 10mm). At present work a new method for producing p-i-n structures was developed to decrease substantially the time required for compensation of silicon by lithium ions and to eliminate at the same time the negative consequences of holding the crystal at a high temperature and under a high voltage. Drift of lithium ions from two ends of prepared samples is conducted to a depth sufficient for the required compensation of the initial acceptor impurity in silicon. The method described above was used to fabricate a batch of Si(Li) detectors with a 1-10 mm thick and 10-110 mm in diameter sensitive region. The thickness of the sensitive region was determined by performing standard measurements and chemical pigmentation. Advantages of detectors are they have improved properties and less time for compensation of lithium ions. (authors)

  7. Comparison of SensL and Hamamatsu 4×4 channel SiPM arrays in gamma spectrometry with scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Grodzicka-Kobylka, M., E-mail: m.grodzicka@ncbj.gov.pl; Szczesniak, T.; Moszyński, M.

    2017-06-01

    The market of Silicon Photomultipliers (SiPMs) consists of many manufacturers that produce their detectors in different technology. Hamamatsu (Japan) and SensL (Ireland) seems to be the most popular companies that produce large SiPM arrays. The aim of this work is characterization and comparison of 4×4 channel SiPM arrays produced by these two producers. Both of the tested SiPMs are made in through-silicon via (TSV) technology, consist of 16, 3×3 mm avalanche photodiode (APD) cells and have fill factor slightly above 60%. The largest difference is a single APD cell size and hence total number of APD cells (55,424 for Hamamatsu, 76,640 for SensL). In the case of SensL SiPM, its spectral response characteristics is shifted slightly toward shorter wavelengths with maximum at 420 nm (450 nm for Hamamatsu). The presented measurements cover selection of the SiPM optimum operating voltage (in respect to energy resolution), verification of the excess noise factor and check of the linearity characteristics. Moreover, the gamma spectrometry with LSO, BGO and CsI:Tl scintillators together with pulse characteristics for these crystals (rise time and fall time) is reported, as well as temperature dependence. The presented measurements show better performance of the SensL array comparing to the Hamamatsu detector.

  8. Silicon PIN diode based electron-gamma coincidence detector system for Noble Gases monitoring.

    Science.gov (United States)

    Khrustalev, K; Popov, V Yu; Popov, Yu S

    2017-08-01

    We present a new second generation SiPIN based electron-photon coincidence detector system developed by Lares Ltd. for use in the Noble Gas measurement systems of the International Monitoring System and the On-site Inspection verification regimes of the Comprehensive Nuclear-Test Ban Treaty (CTBT). The SiPIN provide superior energy resolution for electrons. Our work describes the improvements made in the second generation detector cells and the potential use of such detector systems for other applications such as In-Situ Kr-85 measurements for non-proliferation purposes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Performance of silicon PIN photodiodes at low temperatures and in high magnetic fields

    Czech Academy of Sciences Publication Activity Database

    Wauters, F.; Kraeva, I.S.; Tandecki, M.; Traykov, E.; Van Gorp, S.; Zákoucký, Dalibor; Severijns, N.

    2009-01-01

    Roč. 604, č. 3 (2009), s. 563-567 ISSN 0168-9002 Institutional research plan: CEZ:AV0Z10480505 Keywords : PIN-diode * beta-particle detection * Magnetic field Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.317, year: 2009

  10. Characterization of Hamamatsu 64-channel TSV SiPMs

    Science.gov (United States)

    Renschler, Max; Painter, William; Bisconti, Francesca; Haungs, Andreas; Huber, Thomas; Karus, Michael; Schieler, Harald; Weindl, Andreas

    2018-04-01

    The Hamamatsu UV-light enhanced 64-channel SiPM array of the newest generation (S13361-3050AS-08) has been examined for the purpose of being used for the Silicon Elementary Cell Add-on (SiECA) of the EUSO-SPB balloon experiment. At a room temperature of 19 . 5 °C, the average measured breakdown voltage of the array is (51 . 65 ± 0 . 11) V, the average gain is measured to (2 . 10 ± 0 . 07) ṡ 106 and the average photon detection efficiency results to (44 . 58 ± 1 . 80) % at a wavelength of (423 ± 8) nm and a bias voltage of 55 . 2V. The average dark-count rate is (0 . 69 ± 0 . 12) MHz, equivalent to a dark count rate per SiPM area of (57 ± 12) kHz /mm2, and the crosstalk probability is measured to (3 . 96 ± 0 . 64) %. These results confirm the information given by the manufacturer. Measurements performed with the newly installed Single Photon Calibration Stand at KIT (SPOCK) show the improved sensitivity to photons with wavelengths lower than 400 nm compared to the SiPM array S12642-0808PA-50, which was also investigated for comparison. Additional measurements confirm the strong temperature dependence of the SiPM characteristics as given in the data sheet. All the characterized parameters appear to be sufficiently uniform to build up a focal surface of SiPM arrays fulfilling the requirements for a telescope detecting photons in the UV range.

  11. Silicon PIN diode hybrid arrays for charged particle detection: Building blocks for vertex detectors at the SSC

    International Nuclear Information System (INIS)

    Kramer, G.; Gaalema, S.; Shapiro, S.L.; Dunwoodie, W.M.; Arens, J.F.; Jernigan, J.G.

    1989-05-01

    Two-dimensional arrays of solid state detectors have long been used in visible and infrared systems. Hybrid arrays with separately optimized detector and readout substrates have been extensively developed for infrared sensors. The characteristics and use of these infrared readout chips with silicon PIN diode arrays produced by MICRON SEMICONDUCTOR for detecting high-energy particles are reported. Some of these arrays have been produced in formats as large as 512 /times/ 512 pixels; others have been radiation hardened to total dose levels beyond 1 Mrad. Data generation rates of 380 megasamples/second have been achieved. Analog and digital signal transmission and processing techniques have also been developed to accept and reduce these high data rates. 9 refs., 15 figs., 2 tabs

  12. Phase regeneration of DPSK signals in a silicon waveguide with reverse-biased p-i-n junction

    DEFF Research Database (Denmark)

    Da Ros, Francesco; Vukovic, Dragana; Gajda, Andrzej

    2014-01-01

    Phase regeneration of differential phase-shift keying (DPSK) signals is demonstrated using a silicon waveguide as nonlinear medium for the first time. A p-i-n junction across the waveguide enables decreasing the nonlinear losses introduced by free-carrier absorption (FCA), thus allowing phase......-sensitive extinction ratios as high as 20 dB to be reached under continuous-wave (CW) pumping operation. Furthermore the regeneration properties are investigated under dynamic operation for a 10-Gb/s DPSK signal degraded by phase noise, showing receiver sensitivity improvements above 14 dB. Different phase noise...... frequencies and amplitudes are examined, resulting in an improvement of the performance of the regenerated signal in all the considered cases....

  13. Signal amplification and leakage current suppression in amorphous silicon p-i-n diodes by field profile tailoring

    International Nuclear Information System (INIS)

    Hong, W.S.; Zhong, F.; Mireshghi, A.; Perez-Mendez, V.

    1999-01-01

    The performance of amorphous silicon p-i-n diodes as radiation detectors in terms of signal amplitude can be greatly improved when there is a built-in signal gain mechanism. The authors describe an avalanche gain mechanism which is achieved by introducing stacked intrinsic, p-type, and n-type layers into the diode structure. They replaced the intrinsic layer of the conventional p-i-n diode with i 1 -p-i 2 -n-i 3 multilayers. The i 2 layer (typically 1 ∼ 3 microm) achieves an electric field > 10 6 V/cm, while maintaining the p-i interfaces to the metallic contact at electric fields 4 V/cm, when the diode is fully depleted. For use in photo-diode applications the whole structure is less than 10 microm thick. Avalanche gains of 10 ∼ 50 can be obtained when the diode is biased to ∼ 500 V. Also, dividing the electrodes to strips of 2 microm width and 20 microm pitch reduced the leakage current up to an order of magnitude, and increased light transmission without creating inactive regions

  14. A Low-Noise X-ray Astronomical Silicon-On-Insulator Pixel Detector Using a Pinned Depleted Diode Structure.

    Science.gov (United States)

    Kamehama, Hiroki; Kawahito, Shoji; Shrestha, Sumeet; Nakanishi, Syunta; Yasutomi, Keita; Takeda, Ayaki; Tsuru, Takeshi Go; Arai, Yasuo

    2017-12-23

    This paper presents a novel full-depletion Si X-ray detector based on silicon-on-insulator pixel (SOIPIX) technology using a pinned depleted diode structure, named the SOIPIX-PDD. The SOIPIX-PDD greatly reduces stray capacitance at the charge sensing node, the dark current of the detector, and capacitive coupling between the sensing node and SOI circuits. These features of the SOIPIX-PDD lead to low read noise, resulting high X-ray energy resolution and stable operation of the pixel. The back-gate surface pinning structure using neutralized p-well at the back-gate surface and depleted n-well underneath the p-well for all the pixel area other than the charge sensing node is also essential for preventing hole injection from the p-well by making the potential barrier to hole, reducing dark current from the Si-SiO₂ interface and creating lateral drift field to gather signal electrons in the pixel area into the small charge sensing node. A prototype chip using 0.2 μm SOI technology shows very low readout noise of 11.0 e - rms , low dark current density of 56 pA/cm² at -35 °C and the energy resolution of 200 eV(FWHM) at 5.9 keV and 280 eV (FWHM) at 13.95 keV.

  15. Progress report on the use of hybrid silicon pin diode arrays in high energy physics

    International Nuclear Information System (INIS)

    Shapiro, S.L.; Jernigan, J.G.; Arens, J.F.

    1990-05-01

    We report on the successful effort to develop hybrid PIN diode arrays and to demonstrate their potential as components of vertex detectors. Hybrid pixel arrays have been fabricated by the Hughes Aircraft Co. by bump-bonding readout chips developed by Hughes to an array of PIN diodes manufactured by Micron Semiconductor Inc. These hybrid pixel arrays were constructed in two configurations. One array format has 10 x 64 pixels, each 120 μm square; and the other format has 256 x 156 pixels, each 30 μm square. In both cases, the thickness of the PIN diode layer is 300 μm. Measurements of detector performance show that excellent position resolution can be achieved by interpolation. By determining the centroid of the charge cloud which spreads charge into a number of neighboring pixels, a spatial resolution of a few microns has been attained. The noise has been measured to be about 300 electrons (rms) at room temperature, as expected from KTC and dark current considerations, yielding a signal-to-noise ratio of about 100 for minimum ionizing particles. 4 refs., 17 figs

  16. Defects influence on short circuit current density in p-i-n silicon solar cell

    International Nuclear Information System (INIS)

    Wagah F Mohamad; Alhan M Mustafa

    2006-01-01

    The admittance analysis method has been used to calculate the collection efficiency and the short circuit current density in a-Si:H p-i-n solar cell, as a function of the thickness of i-layer. Its is evident that the results of the short circuit current can be used to determine the optimal thickness of the i-layer of a cell, and it will be more accurate in comparison with the previous studies using a constant generation rate or an empirical exponential function for the generation of charge carriers throughout the i-layer

  17. Highly transparent front electrodes with metal fingers for p-i-n thin-film silicon solar cells

    Directory of Open Access Journals (Sweden)

    Moulin Etienne

    2015-01-01

    Full Text Available The optical and electrical properties of transparent conductive oxides (TCOs, traditionally used in thin-film silicon (TF-Si solar cells as front-electrode materials, are interlinked, such that an increase in TCO transparency is generally achieved at the cost of reduced lateral conductance. Combining a highly transparent TCO front electrode of moderate conductance with metal fingers to support charge collection is a well-established technique in wafer-based technologies or for TF-Si solar cells in the substrate (n-i-p configuration. Here, we extend this concept to TF-Si solar cells in the superstrate (p-i-n configuration. The metal fingers are used in conjunction with a millimeter-scale textured foil, attached to the glass superstrate, which provides an antireflective and retroreflective effect; the latter effect mitigates the shadowing losses induced by the metal fingers. As a result, a substantial increase in power conversion efficiency, from 8.7% to 9.1%, is achieved for 1-μm-thick microcrystalline silicon solar cells deposited on a highly transparent thermally treated aluminum-doped zinc oxide layer combined with silver fingers, compared to cells deposited on a state-of-the-art zinc oxide layer.

  18. Hamamatsu C11204-01 calibration, test and design of a dedicated LabVIEW interface

    International Nuclear Information System (INIS)

    Nocerino, E.; Barbato, F.C.T.; De Asmundis, R.

    2017-01-01

    In the last 50 years solid state devices have been widely used as radiation detectors (photons, betas, fast electrons and heavy ions) thanks to the advantages they offer with respect to photomultiplier tubes technology. However, despite their benefits (low power consumption, small size, low costs), semiconductors are very sensitive to temperature variations. This means that for those experiments using solid state detectors without any thermal control, the correct operation of the detectors is affected by the environmental condition. To solve this problem Hamamatsu Photonics realized the C11204-01 device: a special voltage supply module for silicon photomultipliers which compensates the overvoltage at different temperatures. In the following work we present the results of the calibration of this device and a test we performed on a silicon photomultiplier, by means of a LabVIEW"T"M interface designed ad hoc for this purpose.

  19. Recombination centers and electrical characteristics in silicon power p-i-n diodes irradiated with high energy electrons

    International Nuclear Information System (INIS)

    Fuochi, P.G.; Martelli, A.; Passerini, B.; Zambelli, M.

    1988-01-01

    Recombination centers introduced by irradiation with 12 MeV electrons in large area silicon diodes with p-i-n structure are studied with the Deep Level Transient Spectroscopy technique (DLTS). The effects of these levels on the electrical characteristics of the devices are related to their position Esub(t) in the silicon forbidden gap, their concentration and their electron capture cross section. Changes of defect configuration during an annealing process at 360 0 C have been observed and a detailed analysis of the DLTS spectra has shown a complex defect pattern. Four major recombination centers have been identified: Esub(c) - Esub(t) = 0.17 eV, Esub(c) - Esub(t) = 0.19 eV, Esub(c) -Esub(t) 0.31 eV, Esub(c) - Esub(t) = 0.39 eV, where Esub(c) is the energy corresponding to the lower limit of the conduction band. The first energy level, known as A-center, is the dominant recombination level controlling the minority carrier lifetime after room temperature irradiation. As the annealing proceeds the center at Esub(c) - Esub(t) = 0.31 eV becomes the dominant one. The complex structure of the centers has been studied and demonstrated with the aid of proper modelling implemented on a set of numerical simulation tools. In this way it has been possible to analyze more accurately the defect kinetics during annealing. The study of the defect behaviour during the annealing process has resulted in an improved application of electron irradiation as a standard production technique in the manufacturing process of high power devices. (author)

  20. Dual-polarization wavelength conversion of 16-QAM signals in a single silicon waveguide with a lateral p-i-n diode [Invited

    DEFF Research Database (Denmark)

    Da Ros, Francesco; Gajda, Andrzej; Liebig, Erik

    2018-01-01

    with an optical signal-to-noise ratio penalty below 0.7 dB. High-quality converted signals are generated thanks to the low polarization dependence (≤0.5 dB) and the high conversion efficiency (CE) achievable. The strong Kerr nonlinearity in silicon and the decrease of detrimental free-carrier absorption due......A polarization-diversity loop with a silicon waveguide with a lateral p-i-n diode as a nonlinear medium is used to realize polarization insensitive four-wave mixing. Wavelength conversion of seven dual-polarization 16-quadrature amplitude modulation (QAM) signals at 16 GBd is demonstrated...

  1. Conception and modelling of photo-detection pixels. PIN photodiodes conceived in amorphous silicon for particles detection; Conception et modelisation de pixels de photodetection: Photodiodes PIN en silicium amorphe en vue de leurs utilisations comme detecteurs de particules

    Energy Technology Data Exchange (ETDEWEB)

    Negru, R

    2008-06-15

    The research done has revealed that the a-Si:H is a material ideally suited for the detection of particles, while being resistant to radiation. It also has a low manufacturing cost, is compatible with existing technology and can be deposited over large areas. Thus, despite the low local mobility of charges (30 cm{sup 2}/V/s), a-Si:H is a material of particular interest for manufacturing high-energy particle detection pixels. As a consequence of this, we have studied the feasibility of an experimental pixel stacked structure based on a-Si:H as a basic sensor element for an electromagnetic calorimeter. The structure of such a pixel consists of different components. First, a silicon PIN diode in a-Si:H is fabricated, followed by a bias resistor and a decoupling capacitor. Before such a structure is made and in order to optimize its design, it is essential to have an efficient behavioural model of the various components. Thus, our primary goal was to develop a two-dimensional physical model of the PIN diode using the SILVACO finite element calculation software. This a-Si:H PIN diode two-dimensional physical model allowed us to study the problem of crosstalk between pixels in a matrix structure of detectors. In particular, we concentrated on the leakage current and the current generated in the volume between neighbouring pixels. The successful implementation of this model in SPICE ensures its usefulness in other professional simulators and especially its integration into a complete electronic structure (PIN diode, bias resistor, decoupling capacity and low noise amplifier). Thanks to these modelling tools, we were able to simulate PIN diode structures in a-Si:H with different thicknesses and different dimensions. These simulations have allowed us to predict that the thicker structures are relevant to the design of the pixel detectors for high energy physics. Applications in astronomy, medical imaging and the analysis of the failure of silicon integrated circuits, can

  2. Silicon P.I.N. Junctions used for studies of radiation damage; Etude de l'irradiation aux neutrons rapides du silicium au moyen de jonctions P.I.N

    Energy Technology Data Exchange (ETDEWEB)

    Lanore, J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-06-01

    Irradiation of silicon P.I.N. junction has been studied primarily for the purpose of developing a radiation damage dosimeter, but also for the purpose of investigating silicon itself. It is known that the rate of recombination of electrons and holes is a linear function of defects introduced by neutron irradiation. Two methods have been used to measure that rate of recombination: forward characteristic measurements, recovery time measurements. In order to explain how these two parameters depend on recombination rate we have given a theory of the P.I.N. junction. We have also given an idea of the carrier lifetime dependence versus temperature. Annealing effects in the range of 70 to 700 K have also been studied, we found five annealing stages with corresponding activation energies. As an application for these studies, we developed a radiation damage dosimeter with which we made several experiments in facilities such as Naiade or Marias. (author) [French] L'irradiation de structures P.I.N. etait faite dans le but d'etudier principalement la mise au point d'un dosimetre a ''radiation damage'' et aussi pour etudier plus profondement le silicium lui-meme. On sait que le taux de recombinaison electrons-trous est une fonction lineaire du taux de defauts introduits par irradiation aux neutrons. Deux methodes ont ete utilisees pour atteindre ce taux de recombinaison: mesures de la caracteristique directe, mesures du temps de retournement. Pour expliquer de quelle facon ces parametres dependent du taux de recombinaison. Nous avons donne une theorie de la jonction P.I.N. Nous avons aussi donne l'allure des variations du temps de vie des porteurs en fonction de la temperature. Nous avons d'autre part effectue des recuits entre 70 et 700 K, domaine dans lequel nous avons trouve cinq etapes de ''guerison'' avec les energies d'activation correspondantes. En application de ces etudes nous avons mis ou point un dosimetre a ''radiation damage'' avec lequel nous avons effectue des

  3. Silicon P.I.N. Junctions used for studies of radiation damage; Etude de l'irradiation aux neutrons rapides du silicium au moyen de jonctions P.I.N

    Energy Technology Data Exchange (ETDEWEB)

    Lanore, J. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-06-01

    Irradiation of silicon P.I.N. junction has been studied primarily for the purpose of developing a radiation damage dosimeter, but also for the purpose of investigating silicon itself. It is known that the rate of recombination of electrons and holes is a linear function of defects introduced by neutron irradiation. Two methods have been used to measure that rate of recombination: forward characteristic measurements, recovery time measurements. In order to explain how these two parameters depend on recombination rate we have given a theory of the P.I.N. junction. We have also given an idea of the carrier lifetime dependence versus temperature. Annealing effects in the range of 70 to 700 K have also been studied, we found five annealing stages with corresponding activation energies. As an application for these studies, we developed a radiation damage dosimeter with which we made several experiments in facilities such as Naiade or Marias. (author) [French] L'irradiation de structures P.I.N. etait faite dans le but d'etudier principalement la mise au point d'un dosimetre a ''radiation damage'' et aussi pour etudier plus profondement le silicium lui-meme. On sait que le taux de recombinaison electrons-trous est une fonction lineaire du taux de defauts introduits par irradiation aux neutrons. Deux methodes ont ete utilisees pour atteindre ce taux de recombinaison: mesures de la caracteristique directe, mesures du temps de retournement. Pour expliquer de quelle facon ces parametres dependent du taux de recombinaison. Nous avons donne une theorie de la jonction P.I.N. Nous avons aussi donne l'allure des variations du temps de vie des porteurs en fonction de la temperature. Nous avons d'autre part effectue des recuits entre 70 et 700 K, domaine dans lequel nous avons trouve cinq etapes de ''guerison'' avec les energies d'activation correspondantes. En application de ces etudes nous avons mis ou point un

  4. Contact pin-printing of albumin-fungicide conjugate for silicon nitride-based sensors biofunctionalization: Multi-technique surface analysis for optimum immunoassay performance

    Energy Technology Data Exchange (ETDEWEB)

    Gajos, Katarzyna, E-mail: katarzyna.gajos@doctoral.uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Budkowski, Andrzej [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Tsialla, Zoi; Petrou, Panagiota [Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, NCSR Demokritos, P. Grigoriou & Neapoleos St., Aghia Paraksevi 15310, Athens (Greece); Awsiuk, Kamil; Dąbczyński, Paweł [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Bernasik, Andrzej [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Mickiewicza 30, 30-059 Kraków (Poland); Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Mickiewicza 30, 30-059 Kraków (Poland); Rysz, Jakub [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Misiakos, Konstantinos; Raptis, Ioannis [Department of Microelectronics, Institute of Nanoscience and Nanotechnology, NCSR Demokritos, P. Grigoriou & Neapoleos St., Aghia Paraksevi 15310, Athens (Greece); Kakabakos, Sotirios [Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, NCSR Demokritos, P. Grigoriou & Neapoleos St., Aghia Paraksevi 15310, Athens (Greece)

    2017-07-15

    Highlights: • Contact pin-printing of overlapping probe spots and spotting by hand are compared. • Contact pin-printing favors probe immobilization with two-fold higher surface density. • Incomplete monolayer develops to bilayer as printing solution concentration increases. • Blocking molecules complete probe monolayer but reduce probe bilayer. • Surface immunoreaction increases with probe concentration in printing solution. - Abstract: Mass fabrication of integrated biosensors on silicon chips is facilitated by contact pin-printing, applied for biofunctionalization of individual Si{sub 3}N{sub 4}-based transducers at wafer-scale. To optimize the biofunctionalization for immunochemical (competitive) detection of fungicide thiabendazole (TBZ), Si{sub 3}N{sub 4} surfaces are modified with (3-aminopropyl)triethoxysilane and examined after: immobilization of BSA-TBZ conjugate (probe) from solutions with different concentration, blocking with bovine serum albumin (BSA), and immunoreaction with a mouse monoclonal antibody against TBZ. Nanostructure, surface density, probe composition and coverage uniformity of protein layers are evaluated with Atomic Force Microscopy, Spectroscopic Ellipsometry, Time-of-Flight Secondary Ion Mass Spectrometry and X-ray Photoelectron Spectroscopy. Contact pin-printing of overlapping probe spots is compared with hand spotted areas. Contact pin-printing resulted in two-fold increase of immobilized probe surface density as compared to hand spotting. Regarding BSA-TBZ immobilization, an incomplete monolayer develops into a bilayer as the concentration of BSA-TBZ molecules in the printing solution increases from 25 to 100 μg/mL. Upon blocking, however, a complete protein monolayer is formed for all the BSA-TBZ concentrations used. Free surface sites are filled with BSA for low surface coverage with BSA-TBZ, whereas loosely bound BSA-TBZ molecules are removed from the BSA-TBZ bilayer. As a consequence immunoreaction efficiency

  5. Advances in the project about Pin type silicon radiation detectors; Avances en el proyecto sobre detectores de radiacion de silicio tipo PIN

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez F, J. [Instituto Nacional de Investigaciones Nucleares, Laboratorio de Detectores de Radiacion, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Cerdeira, A.; Aceves, M.; Diaz, A.; Estrada, M.; Rosales, P.; Cabal, A.E.; Montano L, M.; Leyva, A

    1998-07-01

    The obtained advances in the collaboration project ININ-CINVESTAV about development of Pin type semiconductor radiation detectors here are presented. It has been characterized the response to different types of radiation made in CINVESTAV and INAOE. Measurements have been realized with different types of sensitive to charge preamplifiers determining the main characteristics which must be executed to be able to be employed with low capacitance detectors. As applications it has been possible to measure the irradiation time in a mammography machine and X-ray energy spectra have been obtained in the order of 14 KeV, with 4 KeV at ambient temperature. The future actions of project have been indicated and the possible applications of these detectors. (Author)

  6. Contact pin-printing of albumin-fungicide conjugate for silicon nitride-based sensors biofunctionalization: Multi-technique surface analysis for optimum immunoassay performance

    Science.gov (United States)

    Gajos, Katarzyna; Budkowski, Andrzej; Tsialla, Zoi; Petrou, Panagiota; Awsiuk, Kamil; Dąbczyński, Paweł; Bernasik, Andrzej; Rysz, Jakub; Misiakos, Konstantinos; Raptis, Ioannis; Kakabakos, Sotirios

    2017-07-01

    Mass fabrication of integrated biosensors on silicon chips is facilitated by contact pin-printing, applied for biofunctionalization of individual Si3N4-based transducers at wafer-scale. To optimize the biofunctionalization for immunochemical (competitive) detection of fungicide thiabendazole (TBZ), Si3N4 surfaces are modified with (3-aminopropyl)triethoxysilane and examined after: immobilization of BSA-TBZ conjugate (probe) from solutions with different concentration, blocking with bovine serum albumin (BSA), and immunoreaction with a mouse monoclonal antibody against TBZ. Nanostructure, surface density, probe composition and coverage uniformity of protein layers are evaluated with Atomic Force Microscopy, Spectroscopic Ellipsometry, Time-of-Flight Secondary Ion Mass Spectrometry and X-ray Photoelectron Spectroscopy. Contact pin-printing of overlapping probe spots is compared with hand spotted areas. Contact pin-printing resulted in two-fold increase of immobilized probe surface density as compared to hand spotting. Regarding BSA-TBZ immobilization, an incomplete monolayer develops into a bilayer as the concentration of BSA-TBZ molecules in the printing solution increases from 25 to 100 μg/mL. Upon blocking, however, a complete protein monolayer is formed for all the BSA-TBZ concentrations used. Free surface sites are filled with BSA for low surface coverage with BSA-TBZ, whereas loosely bound BSA-TBZ molecules are removed from the BSA-TBZ bilayer. As a consequence immunoreaction efficiency increases with the printing probe concentration.

  7. Systematic study of new types of Hamamatsu MPPCs read out with the NINO ASIC

    CERN Document Server

    Doroud, K; Williams, M C S; Yamamoto, K; Zichichi, A; Zuyeuski, R

    2014-01-01

    Over the last decade there have been commercial TOF-PET scanners constructed using Photo-Multiplier Tubes (PMT) that have achieved View the MathML source~500ps FWHM Coincidence Time Resolution (CTR). A new device known as the Silicon PhotoMultiplier (SiPM) has the potential to overcome some of the limitations of the PMT. Therefore implementing a SiPM based TOF-PET scanner is of high interest. Recently Philips has introduced a TOF-PET scanner that uses digital Silicon PhotoMultipliers (d-SiPMs) which has a CTR of 350 ps. Here we will report on the timing performance of two Hamamatsu 3×3 mm2 analogue-SiPMs read out with the NINO ASIC: this is an ultra-fast amplifier/discriminator with a differential architecture. The differential architecture is very important since the single-ended readout uses the ground as the signal return; as the ground is also the reference level for the discriminators, the result is high crosstalk and degraded time resolution. However differential readout allows the scaling up from a si...

  8. Characterization of the Hamamatsu 8" R5912-MOD Photomultiplier tube

    Science.gov (United States)

    Kaptanoglu, Tanner

    2018-05-01

    Current and future neutrino and direct detection dark matter experiments hope to take advantage of improving technologies in photon detection. Many of these detectors are large, monolithic optical detectors that use relatively low-cost, large-area, and efficient photomultiplier tubes (PMTs). A candidate PMT for future experiments is a newly developed prototype Hamamatsu PMT, the R5912-MOD. In this paper we describe measurements made of the single photoelectron time and charge response of the R5912-MOD, as well as detail some direct comparisons to similar PMTs. Most of these measurements were performed on three R5912-MOD PMTs operating at gains close to 1 × 107. The transit time spread (σ) and the charge peak-to-valley were measured to be on average 680ps and 4.2 respectively. The results of this paper show the R5912-MOD is an excellent candidate for future experiments in several regards, particularly due to its narrow spread in timing.

  9. EFFECT OF SILICON, NITROGEN AND POTASSIUM IN THE INCIDENCE OF TOMATO PIN WORM IN INDUSTRIAL TOMATO PLANTS

    Directory of Open Access Journals (Sweden)

    Marília Cristina dos Santos2*

    2013-12-01

    of two stems per plant. It was observed a decrease in the number of pinworm leaf mines with an increase in silicon and potassium doses and an increase in the number of mines with an increase on nitrogen doses.

  10. Systematic study of new types of Hamamatsu MPPCs read out with the NINO ASIC

    Energy Technology Data Exchange (ETDEWEB)

    Doroud, K. [Museo Storico della Fisica e Centro Studi e Ricerche E. Fermi, Roma (Italy); Rodriguez, A. [CERN, Geneva (Switzerland); ICSC World Laboratory, Geneva (Switzerland); Williams, M.C.S., E-mail: crispin.williams@cern.ch [CERN, Geneva (Switzerland); INFN and Dipartimento di Fisica e Astronomia, Università di Bologna (Italy); Yamamoto, K. [Solid State Division, Hamamatsu Photonics K.K., Hamamatsu (Japan); Zichichi, A. [Museo Storico della Fisica e Centro Studi e Ricerche E. Fermi, Roma (Italy); CERN, Geneva (Switzerland); INFN and Dipartimento di Fisica e Astronomia, Università di Bologna (Italy); Zuyeuski, R. [CERN, Geneva (Switzerland); ICSC World Laboratory, Geneva (Switzerland)

    2014-07-01

    Over the last decade there have been commercial TOF-PET scanners constructed using Photo-Multiplier Tubes (PMT) that have achieved ∼500ps FWHM Coincidence Time Resolution (CTR). A new device known as the Silicon PhotoMultiplier (SiPM) has the potential to overcome some of the limitations of the PMT. Therefore implementing a SiPM based TOF-PET scanner is of high interest. Recently Philips has introduced a TOF-PET scanner that uses digital Silicon PhotoMultipliers (d-SiPMs) which has a CTR of 350 ps. Here we will report on the timing performance of two Hamamatsu 3×3 mm{sup 2} analogue-SiPMs read out with the NINO ASIC: this is an ultra-fast amplifier/discriminator with a differential architecture. The differential architecture is very important since the single-ended readout uses the ground as the signal return; as the ground is also the reference level for the discriminators, the result is high crosstalk and degraded time resolution. However differential readout allows the scaling up from a single cell to a multi-cell device with no loss of time resolution; this becomes increasingly important for the highly segmented detectors that are being built today, both for particle and for medical instrumentation. We obtained excellent results for both the Single Photon Time Resolution (SPTR) and for the CTR using a LYSO crystal of 15 mm length. Such a crystal length has sufficient detection efficiency for 511 keV gammas to make an excellent PET device. The results presented here are proof that a TOF-PET detector with a CTR of 175 ps is indeed possible. This is the first step that defines the starting point of our SuperNINO project.

  11. Systematic study of new types of Hamamatsu MPPCs read out with the NINO ASIC

    International Nuclear Information System (INIS)

    Doroud, K.; Rodriguez, A.; Williams, M.C.S.; Yamamoto, K.; Zichichi, A.; Zuyeuski, R.

    2014-01-01

    Over the last decade there have been commercial TOF-PET scanners constructed using Photo-Multiplier Tubes (PMT) that have achieved ∼500ps FWHM Coincidence Time Resolution (CTR). A new device known as the Silicon PhotoMultiplier (SiPM) has the potential to overcome some of the limitations of the PMT. Therefore implementing a SiPM based TOF-PET scanner is of high interest. Recently Philips has introduced a TOF-PET scanner that uses digital Silicon PhotoMultipliers (d-SiPMs) which has a CTR of 350 ps. Here we will report on the timing performance of two Hamamatsu 3×3 mm 2 analogue-SiPMs read out with the NINO ASIC: this is an ultra-fast amplifier/discriminator with a differential architecture. The differential architecture is very important since the single-ended readout uses the ground as the signal return; as the ground is also the reference level for the discriminators, the result is high crosstalk and degraded time resolution. However differential readout allows the scaling up from a single cell to a multi-cell device with no loss of time resolution; this becomes increasingly important for the highly segmented detectors that are being built today, both for particle and for medical instrumentation. We obtained excellent results for both the Single Photon Time Resolution (SPTR) and for the CTR using a LYSO crystal of 15 mm length. Such a crystal length has sufficient detection efficiency for 511 keV gammas to make an excellent PET device. The results presented here are proof that a TOF-PET detector with a CTR of 175 ps is indeed possible. This is the first step that defines the starting point of our SuperNINO project

  12. Electron transport through rectifying self-assembled monolayer diodes on silicon: Fermi-level pinning at the molecule-metal interface.

    Science.gov (United States)

    Lenfant, S; Guerin, D; Tran Van, F; Chevrot, C; Palacin, S; Bourgoin, J P; Bouloussa, O; Rondelez, F; Vuillaume, D

    2006-07-20

    We report the synthesis and characterization of molecular rectifying diodes on silicon using sequential grafting of self-assembled monolayers of alkyl chains bearing a pi group at their outer end (Si/sigma-pi/metal junctions). We investigate the structure-performance relationships of these molecular devices, and we examine the extent to which the nature of the pi end group (change in the energy position of their molecular orbitals) drives the properties of these molecular diodes. Self-assembled monolayers of alkyl chains (different chain lengths from 6 to 15 methylene groups) functionalized by phenyl, anthracene, pyrene, ethylene dioxythiophene, ethylene dioxyphenyl, thiophene, terthiophene, and quaterthiophene were synthesized and characterized by contact angle measurements, ellipsometry, Fourier transform infrared spectroscopy, and atomic force microscopy. We demonstrate that reasonably well-packed monolayers are obtained in all cases. Their electrical properties were assessed by dc current-voltage characteristics and high-frequency (1-MHz) capacitance measurements. For all of the pi groups investigated here, we observed rectification behavior. These results extend our preliminary work using phenyl and thiophene groups (Lenfant et al., Nano Lett. 2003, 3, 741). The experimental current-voltage curves were analyzed with a simple analytical model, from which we extracted the energy position of the molecular orbital of the pi group in resonance with the Fermi energy of the electrodes. We report experimental studies of the band lineup in these silicon/alkyl pi-conjugated molecule/metal junctions. We conclude that Fermi-level pinning at the pi group/metal interface is mainly responsible for the observed absence of a dependence of the rectification effect on the nature of the pi groups, even though the groups examined were selected to have significant variations in their electronic molecular orbitals.

  13. Pin care

    Science.gov (United States)

    ... Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Pin care URL of this page: //medlineplus.gov/ency/patientinstructions/000481.htm Pin care To use the sharing features on this page, please enable JavaScript. Broken bones can be fixed in surgery with metal ...

  14. Recent measurements on the Hamamatsu 13 in., R8055, PhotoMultiplier Tubes

    International Nuclear Information System (INIS)

    Tsagli, S.; Aggouras, G.; Anassontzis, E.G.; Ball, A.E.; Chinowsky, W.; Fahrun, E.; Grammatikakis, G.; Green, C.; Grieder, P.; Katrivanos, P.; Koske, P.; Ludvig, J.; Markopoulos, E.; Minkowsky, P.; Nygren, D.; Papageorgiou, K.; Przybylski, G.; Resvanis, L.K.; Siotis, I.; Sopher, J.; Staveris, T.; Tsagli, V.; Zhukov, V.A.

    2006-01-01

    The key component of NESTOR, the deep-sea Cherenkov neutrino telescope, built in the Mediterranean, NW of Greece, is the optical module. The NESTOR Optical Module employs a PhotoMultiplier Tube (PMT) in a transparent glass pressure housing. The Hamamatsu PMT R8055-01, 13 in. photomultiplier was selected for NESTOR to replace the old 15'' Hamamatsu PMTs (R2018-03). Extensive tests have been made on the sensitivity, uniformity, time resolution and noise rates of 162 R8055-01 13 in. PMTs

  15. Characterisation of the Hamamatsu photomultipliers for the KM3NeT Neutrino Telescope

    NARCIS (Netherlands)

    Aiello, S.; Akrame, S.E.; Amélineau, F.; Anassontzis, E.G.; Andre, M.; Androulakis, G.; Anghinolfi; Anton, G.; Ardid, M.; Aublin, J.; Avgitas, T.; Baars, M.; Bagatelas, C.; Barbarino, G.; Baret, B.; Barrios-Martí, J.; Belias, A.; Berbee, E.; van den Berg, A.; Bertin, V.; Biagi, S.; Biagioni, A.; Biernoth, C.; Bormuth, R.; Boumaaza, J.; Bourret, S.; Bouwhuis, M.; Bozza, C.; Brânzas, H.; Briukhanova, N.; Bruijn, R.; Brunner, J.; Buis, E.; Buompane, R,; Busto, J.; Calvo, D.; Capone, A.; Caramete, L.; Celli, S.; Chabab, M.; Cherubini, S.; Chiarella, V.; Chiarusi, T.; Circella, M.; Cocimano, R.; Coelho, J.A.B.; Coleiro, A.; Molla, M.C.; Coniglione, R.; Coyle, P.; Creusot, A.; Cuttone, G.; D’Onofrio, A.; Dallier, R.; De Sio, C.; Di Palma, I.; Díaz, A.F.; Distefano, C.; Domi, A.; Donà, R.; Donzaud, C.; Dornic, D.; Dörr, M.; Durocher, M.; Eberl, T.; Van Eijk, D.; El Bojaddaini, I.; Elsaesser, D.; Enzenhöfer, A.; Ferrara, G.; Fusco, L.A.; Gal, T.; Garufi, F.; Gauchery, S.; Geißelsöder, S.; Gialanella, L.; Giorgio, E.; Giuliante, A.; Gozzini, S.R.; Gracia-Ruiz, R.; Graf, K.; Grasso, D.; Grégoire, T.; Grella, G.; Hallmann, S.; van Haren, H.; Heid, T.; Heijboer, A.; Hekalo, A.; Hernandez-Rey, J.J.; Hofestädt, J.; Illuminati, G.; James, C.W.; Jongen, M.; Jongewaard, B.; de Jong, M.; de Jong, P.; Kadler, M.; Kalaczynski, P.; Kalekin, O.; Katz, U.F.; Khan Chowdhury, N.R.; Kieft, G.; Kießling, D.; Koffeman, E.N.; Kooijman, P.; Kouchner, A.; Kreter, M.; Kulikovskiy, V.; Lahmann, R.; Le Breton, A.; Leone, F.; Leonora, E.; Levi, G.; Lincetto, M.; Lonardo, A.; Longhitano, F.; Lotze, M.; Loucatos, S.; Maggi, G.; Manczak, J.; Mannheim, K.; Margiotta, A.; Marinelli, A.; Markou, C.; Martin, L.; Martínez-Mora, J.A.; Martini, A.; Marzaioli, F.; Mele, R.; Melis, K.W.; Migliozzi, P.; Migneco, E.; Mijakowski, P.; Mollo, C.M.; Morganti, M.; Moser, M.; Moussa, A.; Muller, R.; Musumeci, M.; Nauta, L.; Navas, S.; Nicolau, C.A.; Nielsen, C.; Organokov, M.; Orlando, A.; Panagopoulos, V.; Papalashvili, G.; Papaleo, R.; Pavalas, G.E.; Pellegrini, G.; Pellegrino, C.; Pérez Romero, J.; Perrin-Terrin, M.; Piattelli, P.; Pikounis, K.; Pisanti, O.; Poirè, C.; Polydefki, G.; Poma, G.E.; Popa, V.; Post, M.; Pradier, T.; Pühlhofer, G.; Pulvirenti, S.; Quinn, L.; Raffaelli, F.; Randazzo, N.; Razzaque, S.; Real, D.; Resvanis, L.; Reubelt, J.; Riccobene, G.; Richer, M.; Rovelli, A.; Salvadori, I.; Samtleben, D.F.E.; Sánchez-Losa, A.; Sanguineti, M.; Santangelo, A.; Sapienza, P.; Schermer, B.; Sciacca, V.; Seneca, J.; Sgura, I.; Shanidze, R.; Sharma, A.; Simeone, F.; Sinopoulou, A.; Spisso, B.; Spurio, M.; Stavropoulos, D.; Steijger, J.; Stellacci, S.M.; Strandberg, B.; Stransky, D.; Stüven, T.; Taiuti, M.; Tatone, F.; Tayalati, Y.; Tenllado, E.; Thakore, T.; Timmer, P.; Trovato, A.; Tsagkli, S.; Tzamariudaki, E.; Tzanetatos, D.; Valieri, C.; Vallage, B.; Van Elewyck, V.; Versari, F.; Viola, S.; Vivolo, D.; Volkert, M.; de Waardt, L.; Wilms, J.; de Wolf, E.; Zaborov, D.; Zornoza, J.D.; Zúñiga, J.

    2018-01-01

    The Hamamatsu R12199-02 3-inch photomultiplier tube is the photodetector chosen for the first phase of the KM3NeT neutrino telescope. About 7000 photomultipliers have been characterised for dark count rate, timing spread and spurious pulses. The quantum efficiency, the gain and the peak-to-valley

  16. Characterization of the 10-stages R5900 Hamamatsu photomultipliers for the hadronic ATLAS calorimeter

    International Nuclear Information System (INIS)

    Montarou, G.; Bouhemaid, N.; Grenier, Ph.; Crouau, M.; Muanza, G.S.; Poirot, S.; Vazeille, F.; Gil Botella, I.; Hoz, S.G. de la

    1997-01-01

    The measurements carried out, at Clermont on the R5900 Hamamatsu photomultipliers for the ATLAS hadronic calorimeter are summarised. The TILECAL specifications are given. Amplification measurements, dark current measurements, linearity, magnetic sensitivity and the voltage divider optimisation are presented. (K.A.)

  17. Happy Pinning

    DEFF Research Database (Denmark)

    Fausing, Bent

    2012-01-01

    This is about Pinterest, but with a different approach than usual to social networks. Pinterest is an image site par excellence. The images are as Windows that open outwards and also lets us look inwards and displays the soul and heart, the unintentional or pre-conscious desires. Happy Pinning!...

  18. Characterization of 1600 Hamamatsu 16-anode photomultipliers for the MINOS Far detector

    International Nuclear Information System (INIS)

    Lang, K.; Day, J.; Eilerts, S.; Fuqua, S.; Guillen, A.; Kordosky, M.; Lang, M.; Liu, J.; Opaska, W.; Proga, M.; Vahle, P.; Winbow, A.; Drake, G.; Thomas, J.; Andreopoulos, C.; Saoulidou, N.; Stamoulis, P.; Tzanakos, G.; Zois, M.; Weber, A.; Michael, D.

    2005-01-01

    We are reporting results of the characterization of over 1600 multi-anode R5900-00-M16 photomultipliers manufactured by Hamamatsu Photonics K.K., and installed in the MINOS Far detector. We have conducted extensive tests of the uniformity of gain and collection efficiency of individual anodes, the cross-talk among all 16 channels, the dark noise, and the linearity of response. In our studies we used a blue light-emitting diode to illuminate phototubes through 1.2 mm diameter optical fibers. In this paper, we present summaries of the main characteristics of the tested photomultipliers

  19. High spatial resolution gamma imaging detector based on a 5 inch diameter R3292 Hamamatsu PSPMT

    International Nuclear Information System (INIS)

    Wojcik, R.; Majewski, S.; Kross, B.; Weisenberger, A.G.; Steinbach, D.

    1998-01-01

    High resolution imaging gamma-ray detectors were developed using Hamamatsu's 5 inch diameter R3292 position sensitive PMT (PSPMT) and a variety of crystal scintillator arrays. Special readout techniques were used to maximize the active imaging area while reducing the number of readout channels. Spatial resolutions approaching 1 mm were obtained in a broad energy range from 20 to 511 keV. Results are also presented of coupling the scintillator arrays to the PMT via imaging light guides consisting of acrylic optical fibers

  20. Complete tests of 2000 Hamamatsu R7525HA phototubes for the CMS-HF Forward Calorimeter

    International Nuclear Information System (INIS)

    Akgun, U.; Ayan, A.S.; Bruecken, P.; Duru, F.; Guelmez, E.; Mestvirishvilli, A.; Miller, M.; Olson, J.; Onel, Y.; Schmidt, I.

    2005-01-01

    Approximately 2000 PMTs will be used to detect the Cherenkov light generated in quartz fibers embedded in the CMS-HF Forward Calorimeter. The Hamamatsu R7525HA PMT was chosen for this purpose. We measured the transit time, transit time spread, pulse width, rise time, anode dark current, and relative gain for each tube in the test station at University of Iowa. Life-time, gain versus high voltage, and single photoelectron spectrum measurements were also done on a small sample of PMTs. All the tubes were tested to verify that they conform to the HF requirements

  1. First characterization of the Hamamatsu R11265 multi-anode photomultiplier tube

    International Nuclear Information System (INIS)

    Calvi, M.; Cassina, L.; Giachero, A.; Gotti, C.; Maino, M.; Matteuzzi, C.; Pessina, G.

    2014-01-01

    The characterization of the new Hamamatsu R11265-103-M64 multi-anode photomultiplier tube is presented. The sample available in our laboratory was tested and in particular the response to single photon was extensively studied. The gain, the anode uniformity and the dark current were measured. The tube behaviour in a longitudinal magnetic field up to 100 G was studied and the gain loss due to the ageing was quantified. The characteristics and performance of the photomultiplier tube make the R11265-103-M64 particularly tailored for an application in high energy physics experiments, such as in the LHCb Ring Imaging Cherenkov (RICH) detector at LHC. - Highlights: • We tested the new Hamamatsu R11265-103-M64 multi-anode photomultiplier tube. • We studied the response to single photon, the gain and the anode uniformity. • The tube behaviour in a longitudinal magnetic field up to 100 G was studied. • The gain loss due to the aging was quantified

  2. Hydrogenated amorphous silicon p-i-n solar cells deposited under well controlled ion bombardment using pulse-shaped substrate biasing

    NARCIS (Netherlands)

    Wank, M. A.; van Swaaij, R.; R. van de Sanden,; Zeman, M.

    2012-01-01

    We applied pulse-shaped biasing (PSB) to the expanding thermal plasma deposition of intrinsic hydrogenated amorphous silicon layers at substrate temperatures of 200 degrees C and growth rates of about 1?nm/s. Fourier transform infrared spectroscopy of intrinsic films showed a densification with

  3. The HADES-RICH upgrade using Hamamatsu H12700 MAPMTs with DiRICH FEE + Readout

    Science.gov (United States)

    Patel, V.; Traxler, M.

    2018-03-01

    The High Acceptance Di-Electron Spectrometer (HADES) is operational since the year 2000 and uses a hadron blind RICH detector for electron identification. The RICH photon detector is currently replaced by Hamamatsu H12700 MAPMTs with a readout system based on the DiRICH front-end module. The electronic readout chain is being developed as a joint effort of the HADES-, CBM- and PANDA collaborations and will also be used in the photon detectors for the upcoming Compressed Baryonic Matter (CBM) and PANDA experiments at FAIR . This article gives a brief overview on the photomultipliers and their quality assurance test measurements, as well as first measurements of the new DiRICH front-end module in final configurations.

  4. Characterization of the aging and excess noise of a Hamamatsu fine mesh photopentode

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, D., E-mail: fujimoto@phas.ubc.ca; Hearty, C., E-mail: hearty@physics.ubc.ca

    2016-07-01

    The excess noise factor and the aging characteristics of 16 Hamamatsu R11283 photopentodes have been tested. These fine-mesh phototubes are to be paired with pure CsI scintillation crystals considered for use in the endcap calorimeter of the Belle II detector. The average excess noise factor was found to be 1.9±0.1±0.4. The electronic noise of a custom preamplifier produced by the University of Montreal was found as a consequence of this measurement and was 1730±33 electrons, in agreement with previous values. On average, the gain×quantum efficiency was reduced to 92±3% of the initial value after passing an average of 7 C through the anode. This corresponds to 70 years of standard Belle II operation.

  5. Role of SiNx Barrier Layer on the Performances of Polyimide Ga2O3-doped ZnO p-i-n Hydrogenated Amorphous Silicon Thin Film Solar Cells

    Science.gov (United States)

    Wang, Fang-Hsing; Kuo, Hsin-Hui; Yang, Cheng-Fu; Liu, Min-Chu

    2014-01-01

    In this study, silicon nitride (SiNx) thin films were deposited on polyimide (PI) substrates as barrier layers by a plasma enhanced chemical vapor deposition (PECVD) system. The gallium-doped zinc oxide (GZO) thin films were deposited on PI and SiNx/PI substrates at room temperature (RT), 100 and 200 °C by radio frequency (RF) magnetron sputtering. The thicknesses of the GZO and SiNx thin films were controlled at around 160 ± 12 nm and 150 ± 10 nm, respectively. The optimal deposition parameters for the SiNx thin films were a working pressure of 800 × 10−3 Torr, a deposition power of 20 W, a deposition temperature of 200 °C, and gas flowing rates of SiH4 = 20 sccm and NH3 = 210 sccm, respectively. For the GZO/PI and GZO-SiNx/PI structures we had found that the GZO thin films deposited at 100 and 200 °C had higher crystallinity, higher electron mobility, larger carrier concentration, smaller resistivity, and higher optical transmittance ratio. For that, the GZO thin films deposited at 100 and 200 °C on PI and SiNx/PI substrates with thickness of ~000 nm were used to fabricate p-i-n hydrogenated amorphous silicon (α-Si) thin film solar cells. 0.5% HCl solution was used to etch the surfaces of the GZO/PI and GZO-SiNx/PI substrates. Finally, PECVD system was used to deposit α-Si thin film onto the etched surfaces of the GZO/PI and GZO-SiNx/PI substrates to fabricate α-Si thin film solar cells, and the solar cells’ properties were also investigated. We had found that substrates to get the optimally solar cells’ efficiency were 200 °C-deposited GZO-SiNx/PI. PMID:28788494

  6. Role of SiNx Barrier Layer on the Performances of Polyimide Ga2O3-doped ZnO p-i-n Hydrogenated Amorphous Silicon Thin Film Solar Cells

    Directory of Open Access Journals (Sweden)

    Fang-Hsing Wang

    2014-02-01

    Full Text Available In this study, silicon nitride (SiNx thin films were deposited on polyimide (PI substrates as barrier layers by a plasma enhanced chemical vapor deposition (PECVD system. The gallium-doped zinc oxide (GZO thin films were deposited on PI and SiNx/PI substrates at room temperature (RT, 100 and 200 °C by radio frequency (RF magnetron sputtering. The thicknesses of the GZO and SiNx thin films were controlled at around 160 ± 12 nm and 150 ± 10 nm, respectively. The optimal deposition parameters for the SiNx thin films were a working pressure of 800 × 10−3 Torr, a deposition power of 20 W, a deposition temperature of 200 °C, and gas flowing rates of SiH4 = 20 sccm and NH3 = 210 sccm, respectively. For the GZO/PI and GZO-SiNx/PI structures we had found that the GZO thin films deposited at 100 and 200 °C had higher crystallinity, higher electron mobility, larger carrier concentration, smaller resistivity, and higher optical transmittance ratio. For that, the GZO thin films deposited at 100 and 200 °C on PI and SiNx/PI substrates with thickness of ~1000 nm were used to fabricate p-i-n hydrogenated amorphous silicon (α-Si thin film solar cells. 0.5% HCl solution was used to etch the surfaces of the GZO/PI and GZO-SiNx/PI substrates. Finally, PECVD system was used to deposit α-Si thin film onto the etched surfaces of the GZO/PI and GZO-SiNx/PI substrates to fabricate α-Si thin film solar cells, and the solar cells’ properties were also investigated. We had found that substrates to get the optimally solar cells’ efficiency were 200 °C-deposited GZO-SiNx/PI.

  7. Internal fuel pin oxidizer

    International Nuclear Information System (INIS)

    Andrews, M.G.

    1978-01-01

    A nuclear fuel pin has positioned within it material which will decompose to release an oxidizing agent which will react with the cladding of the pin and form a protective oxide film on the internal surface of the cladding

  8. Radon measurements with a PIN photodiode

    International Nuclear Information System (INIS)

    Martin-Martin, A.; Gutierrez-Villanueva, J.L.; Munoz, J.M.; Garcia-Talavera, M.; Adamiec, G.; Iniguez, M.P.

    2006-01-01

    Silicon photodiodes are well suited to detect alphas coming from different sources as neutron reactions or radon daughters. In this work a radon in air detecting device, using an 18x18 mm silicon PIN photodiode is studied. The ionized airborne decay products formed during radon diffusion were focused by an accelerating high voltage to the PIN surface. Several conducting rings were disposed inside a cylindrical PVC vessel in such a way that they reproduced the electric field created by a punctual charge located behind PIN position. Alpha spectra coming from the neutral and ionized species deposited on the PIN surface, dominated by 218 Po and 214 Po progeny peaks, were recorded for varying conditions. Those include radon concentration from a Pylon source, high voltage (thousands of volts) and PIN inverse bias voltage. Different parameters such as temperature and humidity were also registered during data acquisition. The increase in the particle collection efficiency with respect to zero electric field was compared with the corresponding to a parallel plates configuration. A discussion is made in terms of the most appropriate voltages for different radon concentrations

  9. Characterization of the Hamamatsu R11265-103-M64 multi-anode photomultiplier tube

    International Nuclear Information System (INIS)

    Cadamuro, L; Calvi, M; Cassina, L; Giachero, A; Gotti, C; Khanji, B; Maino, M; Matteuzzi, C; Pessina, G

    2014-01-01

    The aim of this paper is to fully characterize the new multi-anode photomultiplier tube R11265-103-M64, produced by Hamamatsu. Its high effective active area (77%), its pixel size, the low dark signal rate and the capability to detect single photon signals make this tube suitable for an application in high energy physics, such as for RICH detectors. Four tubes and two different bias voltage dividers have been tested. The results of a standard characterization of the gain and the anode uniformity, the dark signal rate, the cross-talk and the device behaviour as a function of temperature have been studied. The behaviour of the tube is studied in a longitudinal magnetic field up to 100 Gauss. Shields made of a high permeability material are also investigated. The deterioration of the device performance due to long time operation at intense light exposure is studied. A quantitative analysis of the variation of the gain and the dark signals rate due to the aging is described

  10. Experimental studies on using silicon photodiode as read-out component of CsI(Tl) crystal

    International Nuclear Information System (INIS)

    He Jingtang; Chen Duanbao; Li Zuhao; Mao Yufang; Dong Xiaoli

    1996-01-01

    Experimental studies on using silicon photodiode as the read-out component of CsI(Tl) crystal are reported. The read-out properties of two different types of silicon photodiode produced by Hamamatsu were measured, including relations between energy resolution and bias, shaping time, sensitive area of photodiode and the dimension of the crystal

  11. Digital electronics for 256 anode Hamamatsu H9500 PSPMT arrays in full-volume Compton imagers

    International Nuclear Information System (INIS)

    Harris, J T; Grudberg, P M; Warburton, W K

    2014-01-01

    Ziock et al.'s [1] recent Monte Carlo study of a proposed ''full-volume'' Compton Imaging Camera concluded that simultaneously locating a Compton scatter event's multiple interaction points within a single large scintillator crystal might be possible at 1 mm spatial resolution using a coded aperture mask sandwiched between two light guides and coupled to a position sensitive photomultiplier (PSPMT) to record the output light pattern. The method promises high efficiency at a relatively low cost. They are currently developing a lower resolution prototype using a large cubic scintillator (25.4 cm/side) whose masked face will be tiled with 25 Hamamatsu H9500 PSPMTs (6,400 outputs). XIA has contracted to develop and produce the readout electronics, which present several significant design challenges, including capturing all 6,400 anode outputs individually, with single photon sensitivity, in a compact format that will fit behind the tiled PSPMTs. 10,000 event/sec operation is desired, as is a cost of less than about $50/channel. In our approach, each PSPMT front end integrates the 256 anode signals and 8-1 multiplexes them to 32 differential outputs that are digitized in a PXI card using 4 octal 50 MHz ADCs. The multiplexers run at 8 MHz, sampling each anode at 1 MHz, which becomes the image frame rate. The ADC signals are demultiplexed and digitally filtered to extract the number of photons in each pixel in the full 2-D image. The design has been completed and built and is undergoing evaluation tests at the single PSPMT level

  12. MICROCONTROLLER PIN CONFIGURATION TOOL

    OpenAIRE

    Bhaskar Joshi; F. Mohammed Rizwan; Dr. Rajashree Shettar

    2012-01-01

    Configuring the micro controller with large number of pins is tedious. Latest Infine on microcontroller contains more than 200 pins and each pin has classes of signals. Therefore the complexity of the microcontroller is growing. It evolves looking into thousands of pages of user manual. For a user it will take days to configure the microcontroller with the peripherals. We need an automated tool to configure the microcontroller so that the user can configure the microcontroller without having ...

  13. Modeling crosstalk and afterpulsing in silicon photomultipliers

    International Nuclear Information System (INIS)

    Rosado, J.; Aranda, V.M.; Blanco, F.; Arqueros, F.

    2015-01-01

    An experimental method to characterize the crosstalk and afterpulsing in silicon photomultipliers has been developed and applied to two detectors fabricated by Hamamatsu. An analytical model of optical crosstalk that we presented in a previous publication has been compared with new measurements, confirming our results. Progresses on a statistical model to describe afterpulsing and delayed crosstalk are also shown and compared with preliminary experimental data

  14. Modeling crosstalk and afterpulsing in silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Rosado, J., E-mail: jaime_ros@fis.ucm.es; Aranda, V.M.; Blanco, F.; Arqueros, F.

    2015-07-01

    An experimental method to characterize the crosstalk and afterpulsing in silicon photomultipliers has been developed and applied to two detectors fabricated by Hamamatsu. An analytical model of optical crosstalk that we presented in a previous publication has been compared with new measurements, confirming our results. Progresses on a statistical model to describe afterpulsing and delayed crosstalk are also shown and compared with preliminary experimental data.

  15. First results of systematic studies done with silicon photomultipliers

    International Nuclear Information System (INIS)

    Bosio, C.; Gentile, S.; Kuznetsova, E.; Meddi, F.

    2008-01-01

    Multicell avalanche photodiode structure operated in Geiger mode usually referred as silicon photomultiplier is a new intensively developing technology for photon detection. Insensitivity to magnetic fields, low operation voltage and small size make silicon photomultipliers very attractive for high-energy physics, astrophysics and medical applications. The presented results are obtained during the first steps taken in order to develop a setup and measurement procedures which allow to compare properties of diverse samples of silicon photomultipliers available on market. The response to low-intensity light was studied for silicon photomultipliers produced by CPTA (Russia), Hamamatsu (Japan), ITC-irst (Italy) and SensL (Ireland).

  16. Characterization of the Hamamatsu R11265-103-M64 multi-anode photomultiplier tube for the LHCb RICH Upgrade

    CERN Document Server

    Matteuzzi, C; Carniti, P; Cassina, L; Giachero, A; Gotti, C; Khanji, B; Maino, M; Pessina, G

    2014-01-01

    The Hamamatsu R11265-103-M64 MaPMT is the baseline photon sensor to be used for the LHCb RICH Upgrade detector. This choice has been supported by a large number of tests of this device. This note summarizes the measurements performed by the INFN Milano Bicocca group to characterize the photon detector. A description is provided of the unpublished outcomes and particularly of the more recent developments about the aging of the R11265-103-M64 MaPMT and the test of a whole photon detector RICH Elementary Cell.

  17. Study of PIN diode energy traps created by neutrons

    International Nuclear Information System (INIS)

    Sopko, V; Dammer, J; Sopko, B; Chren, D

    2013-01-01

    Characterization of radiation defects is still ongoing and finds greater application in the increasing radiation doses on semiconductor detectors in experiments. Studying the changes of silicon PIN diode for high doses of radiation is the fundamental motivation for our measurements. In this article we describe the behavior of the PIN diode and development of the disorder caused by neutrons from a 252Cf and doses up to 8 Gy. The calibration curve for PIN diode shows the effect of disorders as the changes of the voltampere characteristics depending on the dose of neutron irradiation. The measured values for defects are in good agreement with created energy traps.

  18. PINS Spectrum Identification Guide

    Energy Technology Data Exchange (ETDEWEB)

    A.J. Caffrey

    2012-03-01

    The Portable Isotopic Neutron Spectroscopy—PINS, for short—system identifies the chemicals inside munitions and containers without opening them, a decided safety advantage if the fill chemical is a hazardous substance like a chemical warfare agent or an explosive. The PINS Spectrum Identification Guide is intended as a reference for technical professionals responsible for the interpretation of PINS gamma-ray spectra. The guide is divided into two parts. The three chapters that constitute Part I cover the science and technology of PINS. Neutron activation analysis is the focus of Chapter 1. Chapter 2 explores PINS hardware, software, and related operational issues. Gamma-ray spectral analysis basics are introduced in Chapter 3. The six chapters of Part II cover the identification of PINS spectra in detail. Like the PINS decision tree logic, these chapters are organized by chemical element: phosphorus-based chemicals, chlorine-based chemicals, etc. These descriptions of hazardous, toxic, and/or explosive chemicals conclude with a chapter on the identification of the inert chemicals, e.g. sand, used to fill practice munitions.

  19. Fuel pin transfer tool

    International Nuclear Information System (INIS)

    Patenaude, R. S.

    1985-01-01

    A fuel pin transfer tool has a latching device of the collet type attached to a first member movable vertically through a long work stroke enabling a fuel pin in an under water assembly to be engaged and withdrawn therefrom or placed therein and released. The latching device has a collet provided with a plurality of resilient fingers having cam portions normally spaced apart to receive the upper end of a fuel pin between them and a second member, movable vertically through a short stroke relative to the first member is provided with cam portions engageable with those of the fingers and is yieldably and resiliently held in a raised position in which its cam portions engage those of the fingers and force the fingers into their pin-gripping positions. When a predetermined force is applied to the second member, it is so moved that its cam portions are disengaged from the cam portions of the fingers permitting the latter to move into their normal relationship in which a gripped pin is released or another pin received but with their pin-gripping relationship positively re-established and maintained once the force on the tubular member is lessened. Movement of the first member in either direction and movement of the second member into its raised position is attended by forces inadequate to affect the integrity of fuel pin cladding. That force is applied in the preferred embodiment, by a power operated actuator which is within the upper portion of a housing and, in the preferred embodiment, carried by the long stroke member but always in the upper housing portion which is of a material sufficiently translucent to enable the actuator to be observed throughout the work stroke and is sufficiently light in weight to prevent the tool from being top heavy

  20. Flux Pinning in Superconductors

    CERN Document Server

    Matsushita, Teruo

    2007-01-01

    The book covers the flux pinning mechanisms and properties and the electromagnetic phenomena caused by the flux pinning common for metallic, high-Tc and MgB2 superconductors. The condensation energy interaction known for normal precipitates or grain boundaries and the kinetic energy interaction proposed for artificial Nb pins in Nb-Ti, etc., are introduced for the pinning mechanism. Summation theories to derive the critical current density are discussed in detail. Irreversible magnetization and AC loss caused by the flux pinning are also discussed. The loss originally stems from the ohmic dissipation of normal electrons in the normal core driven by the electric field induced by the flux motion. The readers will learn why the resultant loss is of hysteresis type in spite of such mechanism. The influence of the flux pinning on the vortex phase diagram in high Tc superconductors is discussed, and the dependencies of the irreversibility field are also described on other quantities such as anisotropy of supercondu...

  1. Reliability studies on Si PIN photodiodes under Co-60 gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakara Rao, Y. P. [Integrated Circuits Division, Bharat Electronics Limited, Bangalore, Karnataka-560013 (India) and Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore, Karnataka-570006 (India); Praveen, K. C.; Gnana Prakash, A. P. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore, Karnataka-570006 (India); Rani, Y. Rejeena [Integrated Circuits Division, Bharat Electronics Limited, Bangalore, Karnataka-560013 (India)

    2013-02-05

    Silicon PIN photodiodes were fabricated with 250 nm SiO{sub 2} antireflective coating (ARC). The changes in the electrical characteristics, capacitance-voltage characteristics and spectral response after gamma irradiation are systematically studied to estimate the radiation tolerance up to 10 Mrad. The different characteristics studied in this investigation demonstrate that Si PIN photodiodes are suitable for high radiation environment.

  2. PINS-3X Operations

    Energy Technology Data Exchange (ETDEWEB)

    E.H. Seabury

    2013-09-01

    Idaho National Laboratory’s (INL’s) Portable Isotopic Neutron Spectroscopy System (PINS) non-intrusively identifies the chemical fill of munitions and sealed containers. The PINS-3X variant of the system is used to identify explosives and uses a deuterium-tritium (DT) electronic neutron generator (ENG) as the neutron source. Use of the system, including possession and use of the neutron generator and shipment of the system components requires compliance with a number of regulations. This report outlines some of these requirements as well as some of the requirements in using the system outside of INL.

  3. SVX II a silicon vertex detector for run II of the tevatron

    International Nuclear Information System (INIS)

    Bortoletto, D.

    1994-11-01

    A microstrip silicon detector SVX II has been proposed for the upgrade of the vertex detector of the CDF experiment to be installed for run II of the Tevatron in 1998. Three barrels of four layers of double sided detectors will cover the interaction region. The requirement of the silicon tracker and the specification of the sensors are discussed together with the proposed R ampersand D to verify the performance of the prototypes detectors produced by Sintef, Micron and Hamamatsu

  4. Pinning Down versus Density

    OpenAIRE

    Juhász, István; Soukup, Lajos; Szentmiklóssy, Zoltán

    2015-01-01

    The pinning down number $ {pd}(X)$ of a topological space $X$ is the smallest cardinal $\\kappa$ such that for any neighborhood assignment $U:X\\to \\tau_X$ there is a set $A\\in [X]^\\kappa$ with $A\\cap U(x)\

  5. Pin clad strains in Phenix

    International Nuclear Information System (INIS)

    Languille, A.

    1979-07-01

    The Phenix reactor has operated for 4 years in a satisfactory manner. The first 2 sub-assembly loadings contained pins clad in solution treated 316. The principal pin strains are: diametral strain (swelling and irradiation creep), ovality and spiral bending of the pin (interaction of wire and pin cluster and wrapper). A pin cluster irradiated to a dose of 80 dpa F reached a pin diameter strain of 5%. This strain is principally due to swelling (low fission gas pressure). The principal parameters governing the swelling are instantaneous dose, time and temperature for a given type of pin cladding. Other types of steel are or will be irradiated in Phenix. In particular, cold-worked titanium stabilised 316 steel should contribute towards a reduction in the pin clad strains and increase the target burn-up in this reactor. (author)

  6. Size of silicon strip sensor from 6 inch wafer (right) compared to that from a 4 inch wafer (left).

    CERN Multimedia

    Honma, Alan

    1999-01-01

    Silicon strip sensors made from 6 inch wafers will allow for much larger surface area coverage at a reduced cost per unit surface area. A prototype sensor of size 8cm x 11cm made by Hamamatsu from a 6 inch wafer is shown next to a traditional 6cm x 6cm sensor from a 4 inch wafer.

  7. Radiation monitoring with CVD diamonds and PIN diodes at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Bruinsma, M. [University of California Irvine, Irvine, CA 92697 (United States); Burchat, P. [Stanford University, Stanford, CA 94305-4060 (United States); Curry, S. [University of California Irvine, Irvine, CA 92697 (United States)], E-mail: scurry@slac.stanford.edu; Edwards, A.J. [Stanford University, Stanford, CA 94305-4060 (United States); Kagan, H.; Kass, R. [Ohio State University, Columbus, OH 43210 (United States); Kirkby, D. [University of California Irvine, Irvine, CA 92697 (United States); Majewski, S.; Petersen, B.A. [Stanford University, Stanford, CA 94305-4060 (United States)

    2007-12-11

    The BaBar experiment at the Stanford Linear Accelerator Center has been using two polycrystalline chemical vapor deposition (pCVD) diamonds and 12 silicon PIN diodes for radiation monitoring and protection of the Silicon Vertex Tracker (SVT). We have used the pCVD diamonds for more than 3 years, and the PIN diodes for 7 years. We will describe the SVT and SVT radiation monitoring system as well as the operational difficulties and radiation damage effects on the PIN diodes and pCVD diamonds in a high-energy physics environment.

  8. Nuclear fuel pin

    International Nuclear Information System (INIS)

    Hartley, Kenneth; Moulding, T.L.J.; Rostron, Norman.

    1979-01-01

    Fuel pin for use in fast breeder nuclear reactors containing fissile and fertile areas of which the fissile and fertile materials do not mix. The fissile material takes the shape of large and small diameter microspheres (the small diameter microspheres can pass through the interstices between the large microspheres). The barrier layers being composed of microspheres with a diameter situated between those of the large and small microspheres ensure that the materials do not mix [fr

  9. Pinning in nonmagnetic borocarbides

    International Nuclear Information System (INIS)

    Zholobenko, A.N.; Mikitik, G.P.; Fil, V.D.; Kim, J.D.; Lee, S.I.

    2005-01-01

    The field dependences of the Labush parameter in nonmagnetic borocarbides are measured by the method which does not require the free flux flow regime. The anticipated critical current densities are estimated. These values are by two orders of magnitude higher than those measured 'directly' in transport (magnetic) experiments. The giant peak-effect in the field dependences of the Labush parameter is revealed in the Y-based borocarbides. Its behavior is well approximated by the collective pinning theory

  10. Time-of-flight resolution of scintillating counters with Burle 85001 microchannel plate photomultipliers in comparison with Hamamatsu R2083

    Energy Technology Data Exchange (ETDEWEB)

    Baturin, V. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Burkert, V. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Kim, W. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of)]. E-mail: wooyoung@jlab.org; Majewsky, S. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Park, K. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Popov, V. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Smith, E.S. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Son, D. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Stepanyan, S.S. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Zorn, C. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)

    2006-06-15

    Improvements in the time resolution of the CEBAF Large Acceptance Spectrometer (CLAS) below {approx}50ps will be required for experiments using the planned upgraded accelerator facility at Jefferson Lab. The improved time resolution will allow particle identification using time-of-flight techniques to be used effectively up to the proposed operating energy of 12GeV. The challenge of achieving this time resolution over a relatively large area is compounded because the photomultipliers (PM) in the CLAS 'time-zero' scintillating counters must operate in very high magnetic fields. Therefore, we have studied the resolution of 'time-zero' prototypes with microchannel plate PMs 85001-501 from Burle. For reference and comparison, measurements were also made using the standard PMs R2083 from Hamamatsu using two timing methods. The cosmic ray method, which utilizes three identical scintillating counters (Bicron BC-408, 2x3x50cm{sup 3}) with PMs at the ends, yields {sigma}{sub R2083}=59.1+/-0.7ps. The location method of particles from a radiative source with known coordinates has been used to compare timing resolutions of R2083 and 85001-501. This method yields {sigma}{sub R2083}=59.5+/-0.7ps and it also provides an estimate of the number of primary photoelectrons. For the microchannel plate PM from Burle the method yields {sigma}{sub 85001}=130+/-4ps due to lower number of primary photoelectrons.

  11. Time resolution of Burle 85001 micro-channel plate photo-multipliers in comparison with Hamamatsu R2083

    Energy Technology Data Exchange (ETDEWEB)

    V. Baturin; V. Burkert; W. Kim; S. Majewsky; D. Nekrasov; K. Park; V. Popov; E. S. Smith; D. Son; S. S. Stepanyan; C. Zorn

    2005-06-01

    The CLAS detector will require improvements in its particle identification system to take advantage of the higher energies provided by the Jefferson Laboratory accelerator upgrade to 12 GeV. To this end, we have studied the timing characteristics of the micro-channel plate photo-multiplier 85001 from Burle, which can be operated in a high magnetic field environment. For reference and comparison, measurements were also made using the standard PMT R2083 from Hamamatsu using two timing methods. The cosmic ray method, which utilizes three identical scintillating counters 2cm x 3cm x 50cm with PMs at the ends, yields 59.1(0.7)ps. The location method of particles from radiative source with known coordinates has been used to compare timing resolutions of R2083 and Burle-85001. This ''coordinate method'' requires only one counter instrumented with two PMs and it yields 59.5(0.7)ps. For the micro-channel plate photomultiplier from Burle with an external amplification of 10 to the signals, the co ordinate method yields 130(4)ps. This method also makes it possible to estimate the number of primary photo-electrons.

  12. Seasonal variations of neuromotor development by 14 months of age: Hamamatsu Birth Cohort for mothers and children (HBC Study.

    Directory of Open Access Journals (Sweden)

    Kenji J Tsuchiya

    Full Text Available The present study aimed at investigating whether neuromotor development, from birth to 14 months of age, shows seasonal, cyclic patterns in association with months of birth. Study participants were 742 infants enrolled in the Hamamatsu Birth Cohort (HBC Study and followed-up from birth to the 14th month of age. Gross motor skills were assessed at the ages of 6, 10, and 14 months, using Mullen Scales of Early Learning. The score at each assessment was regressed onto a trigonometric function of months of birth, with an adjustment for potential confounders. Gross motor scores at the 6th and 10th months showed significant 1-year-cycle variations, peaking among March- and April-born infants, and among February-born infants, respectively. Changes in gross motor scores between the 10th and 14th months also showed a cyclic variation, peaking among July- and August-born infants. Due to this complementary effect, gross motor scores at the 14th month did not show seasonality. Neuromotor development showed cyclic seasonality during the first year of life. The effects brought about by month of birth disappeared around 1 year of age, and warmer months seemed to accelerate the neuromotor development.

  13. Amorphous silicon based radiation detectors

    International Nuclear Information System (INIS)

    Perez-Mendez, V.; Cho, G.; Drewery, J.; Jing, T.; Kaplan, S.N.; Qureshi, S.; Wildermuth, D.; Fujieda, I.; Street, R.A.

    1991-07-01

    We describe the characteristics of thin(1 μm) and thick (>30μm) hydrogenated amorphous silicon p-i-n diodes which are optimized for detecting and recording the spatial distribution of charged particles, x-rays and γ rays. For x-ray, γ ray, and charged particle detection we can use thin p-i-n photosensitive diode arrays coupled to evaporated layers of suitable scintillators. For direct detection of charged particles with high resistance to radiation damage, we use the thick p-i-n diode arrays. 13 refs., 7 figs

  14. Simulation of Silicon Photomultiplier Signals

    Science.gov (United States)

    Seifert, Stefan; van Dam, Herman T.; Huizenga, Jan; Vinke, Ruud; Dendooven, Peter; Lohner, Herbert; Schaart, Dennis R.

    2009-12-01

    In a silicon photomultiplier (SiPM), also referred to as multi-pixel photon counter (MPPC), many Geiger-mode avalanche photodiodes (GM-APDs) are connected in parallel so as to combine the photon counting capabilities of each of these so-called microcells into a proportional light sensor. The discharge of a single microcell is relatively well understood and electronic models exist to simulate this process. In this paper we introduce an extended model that is able to simulate the simultaneous discharge of multiple cells. This model is used to predict the SiPM signal in response to fast light pulses as a function of the number of fired cells, taking into account the influence of the input impedance of the SiPM preamplifier. The model predicts that the electronic signal is not proportional to the number of fired cells if the preamplifier input impedance is not zero. This effect becomes more important for SiPMs with lower parasitic capacitance (which otherwise is a favorable property). The model is validated by comparing its predictions to experimental data obtained with two different SiPMs (Hamamatsu S10362-11-25u and Hamamatsu S10362-33-25c) illuminated with ps laser pulses. The experimental results are in good agreement with the model predictions.

  15. Transformation of Helicopter PinS Procedures for Airplanes

    Directory of Open Access Journals (Sweden)

    Jakub Kraus

    2013-09-01

    Full Text Available This article deals with the possibility to use existing helicopter Point in Space procedures with minor changes for airplanes. The basis is to find parts of PinS procedures that need to be changed, suggest these changes, and then determine whether the revised procedures could be usable and could bring the benefits for airplane operations.

  16. Pinning, de-pinning and re-pinning of a slowly varying rivulet

    KAUST Repository

    Paterson, C.; Wilson, S.K.; Duffy, B.R.

    2013-01-01

    The solutions for the unidirectional flow of a thin rivulet with prescribed volume flux down an inclined planar substrate are used to describe the locally unidirectional flow of a rivulet with constant width (i.e. pinned contact lines) but slowly varying contact angle as well as the possible pinning and subsequent de-pinning of a rivulet with constant contact angle and the possible de-pinning and subsequent re-pinning of a rivulet with constant width as they flow in the azimuthal direction from the top to the bottom of a large horizontal cylinder. Despite being the same locally, the global behaviour of a rivulet with constant width can be very different from that of a rivulet with constant contact angle. In particular, while a rivulet with constant non-zero contact angle can always run from the top to the bottom of the cylinder, the behaviour of a rivulet with constant width depends on the value of the width. Specifically, while a narrow rivulet can run all the way from the top to the bottom of the cylinder, a wide rivulet can run from the top of the cylinder only to a critical azimuthal angle. The scenario in which the hitherto pinned contact lines of the rivulet de-pin at the critical azimuthal angle and the rivulet runs from the critical azimuthal angle to the bottom of the cylinder with zero contact angle but slowly varying width is discussed. The pinning and de-pinning of a rivulet with constant contact angle, and the corresponding situation involving the de-pinning and re-pinning of a rivulet with constant width at a non-zero contact angle which generalises the de-pinning at zero contact angle discussed earlier, are described. In the latter situation, the mass of fluid on the cylinder is found to be a monotonically increasing function of the constant width. © 2013 Elsevier Masson SAS. All rights reserved.

  17. Pinning, de-pinning and re-pinning of a slowly varying rivulet

    KAUST Repository

    Paterson, C.

    2013-09-01

    The solutions for the unidirectional flow of a thin rivulet with prescribed volume flux down an inclined planar substrate are used to describe the locally unidirectional flow of a rivulet with constant width (i.e. pinned contact lines) but slowly varying contact angle as well as the possible pinning and subsequent de-pinning of a rivulet with constant contact angle and the possible de-pinning and subsequent re-pinning of a rivulet with constant width as they flow in the azimuthal direction from the top to the bottom of a large horizontal cylinder. Despite being the same locally, the global behaviour of a rivulet with constant width can be very different from that of a rivulet with constant contact angle. In particular, while a rivulet with constant non-zero contact angle can always run from the top to the bottom of the cylinder, the behaviour of a rivulet with constant width depends on the value of the width. Specifically, while a narrow rivulet can run all the way from the top to the bottom of the cylinder, a wide rivulet can run from the top of the cylinder only to a critical azimuthal angle. The scenario in which the hitherto pinned contact lines of the rivulet de-pin at the critical azimuthal angle and the rivulet runs from the critical azimuthal angle to the bottom of the cylinder with zero contact angle but slowly varying width is discussed. The pinning and de-pinning of a rivulet with constant contact angle, and the corresponding situation involving the de-pinning and re-pinning of a rivulet with constant width at a non-zero contact angle which generalises the de-pinning at zero contact angle discussed earlier, are described. In the latter situation, the mass of fluid on the cylinder is found to be a monotonically increasing function of the constant width. © 2013 Elsevier Masson SAS. All rights reserved.

  18. Study of the Radiation-Hardness of VCSEL and PIN

    CERN Document Server

    Gan, K K; Fernando, W; Kagan, H P; Kass, R D; Lebbai, M R M; Merritt, H; Moore, J R; Nagarkar, A; Rizatdinova, F; Skubic, P L; Smith, D S; Strang, M

    2009-01-01

    The silicon trackers of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN (Geneva) use optical links for data transmission. An upgrade of the trackers is planned for the Super LHC (SLHC), an upgraded LHC with ten times higher luminosity. We study the radiation-hardness of VCSELs (Vertical-Cavity Surface-Emitting Laser) and GaAs and silicon PINs using 24 GeV/c protons at CERN for possible application in the data transmission upgrade. The optical power of VCSEL arrays decreases significantly after the irradiation but can be partially annealed with high drive currents. The responsivities of the PIN diodes also decrease significantly after irradiation, but can be recovered by operating at higher bias voltage. This provides a simple mechanism to recover from the radiation damage.

  19. Vortex pinning and creep experiments

    International Nuclear Information System (INIS)

    Kes, P.H.

    1991-01-01

    A brief review of basic flux-pinning and flux-creep ingredients and a selection of experimental results on high-temperature-superconductivity compounds is presented. Emphasis is put on recent results and on those properties which are central to the emerging understanding of the flux-pinning and flux-creep mechanisms of these fascinating materials

  20. Panoramic irradiator dose mapping with pin photodiodes

    International Nuclear Information System (INIS)

    Ferreira, Danilo Cardenuto; Napolitano, Celia Marina; Bueno, Carmen Cecilia

    2011-01-01

    In this work we study the possibility of using commercial silicon PIN photodiodes (Siemens, SFH 00206) for dose mapping in the Panoramic Irradiator facility at IPEN-CNEN/SP. The chosen photodiode, that is encased in 1.2 mm thickness polymer layer, displays promising dosimetric characteristics such as small size (sensitive area of 7.00 mm 2 ), high sensitivity and low dark current (≅ 300 pA, at 0 V) together with low-cost and wide availability. The Panoramic facility is an irradiator Type II with absorbed dose certificated by International Dose Assurance Service (IDAS) offered by the International Agency Energy Atomic (IAEA). The charge registered by the diode as a function of the absorbed dose was in excellent agreement with that one calibrated by IDAS. Besides this, the easy handling and fast response of the SFH00206 diode compared to Fricke chemical dosimeters encouraged us to perform dose mapping around the source. (author)

  1. Automated fuel pin loading system

    Science.gov (United States)

    Christiansen, D.W.; Brown, W.F.; Steffen, J.M.

    An automated loading system for nuclear reactor fuel elements utilizes a gravity feed conveyor which permits individual fuel pins to roll along a constrained path perpendicular to their respective lengths. The individual lengths of fuel cladding are directed onto movable transports, where they are aligned coaxially with the axes of associated handling equipment at appropriate production stations. Each fuel pin can be be reciprocated axially and/or rotated about its axis as required during handling steps. The fuel pins are inerted as a batch prior to welding of end caps by one of two disclosed welding systems.

  2. Silicon photomultiplier as a detector of Cherenkov photons

    International Nuclear Information System (INIS)

    Korpar, S.; Dolenec, R.; Hara, K.; Iijima, T.; Krizan, P.; Mazuka, Y.; Pestotnik, R.; Stanovnik, A.; Yamaoka, M.

    2008-01-01

    A novel photon detector-i.e. the silicon photomultiplier-whose main advantage over conventional photomultiplier tubes is the operation in high magnetic fields, has been tested as a photon detector in a proximity focusing RICH with aerogel radiator. This type of RICH counter is proposed for the upgrade of the Belle detector at the KEK B-factory. Recently produced silicon photomultipliers show less noise and have larger size, which are important issues for a large area photon detector. We measured the single photon pulse height distribution, the timing resolution and the position sensitivity for different silicon photomultipliers (Hamamatsu MPPC HC025, HC050, and HC100). The silicon photomultipliers were then used to detect Cherenkov photons emitted by cosmic ray particles in a proximity focusing aerogel RICH. Various light guides were investigated in order to increase the detection efficiency

  3. Pinning down the axion

    International Nuclear Information System (INIS)

    Dabholkar, A.; Quashnock, J.M.

    1990-01-01

    Davis has argued that, without inflation, the decay of axionic strings is the primary source of axions. This implies a cosmological lower bound on the axion mass of 10 -5 to 10 -3 eV. In order to obtain a sharper bound it is essential to know the spectrum of emitted axions and the detailed motion of a global string strongly coupled to the axionic field. To this end, we obtain self-consistent, renormalized equations that describe the dynamics of a radiating global string interacting with its surrounding axionic field. We describe the numerical formalism for evolving string trajectories using these equations. From the numerical and analytical evidence we argue that, with appropriate renormalization, the motion of an interacting cosmic string loop can be well approximated by the motion of a free Nambu-Goto string. This implies a lower bound for the axion mass of 10 -3 eV. Together with the recent upper bound of 4x10 -4 eV from the supernova SN1987a, this marginally rules out the invisible axion, or at least pins down the axion mass to a very narrow window around 10 -3 eV. This still leaves open the window around 2 eV for hardronic axions, but in that case the axion is no longer a serious dark matter candidate. (orig.)

  4. Pinning Mechanisms in YBCO Tapes

    CERN Document Server

    Spera, Marcello; Ballarino, Amalia

    2015-01-01

    In this thesis work, a study on flux pinning mechanisms of commercial YBCO tapes is presented. This study has been performed via critical current characterization using transport (via direct I-V curves) and magnetization (via a Vibrating Sample Magnetometer) measurements. The latter ones turned out to be better concerning the comprehension of the pinning landscape of the provided samples, as a wider range of magnetic fields and temperatures is available for those measurements in the setup I used. The comparison of the experimental data with existing theoretical models allowed me to draw a picture of the pinning mechanisms underlying in each sample, and they turned out to be quite different one another. Moreover, for high-performance research tapes, another interesting feature has been found: the counterplay between the self-field critical current and the in-field one. Very well engineered artificial pinning structures limit the self-field critical current density due to the hi...

  5. Automated system for loading nuclear fuel pins

    International Nuclear Information System (INIS)

    Marshall, J.L.

    1983-10-01

    A completely automatic and remotely controlled fuel pin fabrication system is being designed by the Westinghouse Hanford Company. The Pin Operations System will produce fuel pins for the Fast Flux Test Facility (FFTF) and the Clinch River Breeder Reactor Plant (CRBRP). The system will assemble fuel pin components into cladding tubes in a controlled environment. After fuel loading, the pins are filled with helium, the tag gas capsules are inserted, and the top end cap welded. Following welding, the pins are surveyed to assure they are free of contamination and then the pins are helium leak tested

  6. Silicon Photomultiplier charaterization

    Science.gov (United States)

    Munoz, Leonel; Osornio, Leo; Para, Adam

    2014-03-01

    Silicon Photo Multiples (SiPM's) are relatively new photon detectors. They offer many advantages compared to photo multiplier tubes (PMT's) such as insensitivity to magnetic field, robustness at varying lighting levels, and low cost. The SiPM output wave forms are poorly understood. The experiment conducted collected waveforms of responses of Hamamatsu SiPM to incident laser pulse at varying temperatures and bias voltages. Ambient noise was characterized at all temperatures and bias voltages by averaging the waveforms. Pulse shape of the SiPM response was determined under different operating conditions: the pulse shape is nearly independent of the bias voltage but exhibits strong variation with temperature, consistent with the temperature variation of the quenching resistor. Amplitude of responses of the SiPM to low intensity laser light shows many peaks corresponding to the detection of 1,2,3 etc. photons. Amplitude of these pulses depends linearly on the bias voltage, enabling determination of the breakdown voltage at each temperature. Poisson statistics has been used to determine the average number of detected photons at each operating conditions. Department of Education Grant No. P0315090007 and the Department of Energy/ Fermi National Accelerator Laboratory.

  7. 75 MeV boron ion irradiation studies on Si PIN photodiodes

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakara Rao, Y.P.; Praveen, K.C. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570006 (India); Rejeena Rani, Y. [Integrated Circuits Division, Bharat Electronics Limited, Bangalore 560013, Karnataka (India); Tripathi, Ambuj [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Gnana Prakash, A.P., E-mail: gnanap@hotmail.com [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570006 (India)

    2013-12-01

    The highly sensitive silicon PIN photodiodes were fabricated to use in radiation environments. The Si PIN photodiodes are coated with 150 nm silicon dioxide (SiO{sub 2}) as anti-reflective (AR) coating. The presence of AR coating on the performance of irradiated PIN photodiodes is studied up to a total dose of 10 Mrad. The effects of 75 MeV boron (B{sup 5+}) ions and {sup 60}Co gamma radiation on the I–V, C–V and spectral responses of PIN photodiodes were studied systematically to understand the radiation tolerance of the devices. The 75 MeV B{sup 5+} irradiation results are compared with {sup 60}Co gamma irradiated results in the same dose range for 1 mm × 1 mm and 10 mm × 10 mm active area PIN photodiodes. The irradiation results show that the ion irradiated PIN photodiodes show more degradation when compared {sup 60}Co gamma irradiated devices. The irradiation results are presented in this paper and the possible mechanism behind the degradation of photodiodes is also discussed in the paper.

  8. Enhanced pinning in superconducting thin films with graded pinning landscapes

    Science.gov (United States)

    Motta, M.; Colauto, F.; Ortiz, W. A.; Fritzsche, J.; Cuppens, J.; Gillijns, W.; Moshchalkov, V. V.; Johansen, T. H.; Sanchez, A.; Silhanek, A. V.

    2013-05-01

    A graded distribution of antidots in superconducting a-Mo79Ge21 thin films has been investigated by magnetization and magneto-optical imaging measurements. The pinning landscape has maximum density at the sample border, decreasing linearly towards the center. Its overall performance is noticeably superior than that for a sample with uniformly distributed antidots: For high temperatures and low fields, the critical current is enhanced, whereas the region of thermomagnetic instabilities in the field-temperature diagram is significantly suppressed. These findings confirm the relevance of graded landscapes on the enhancement of pinning efficiency, as recently predicted by Misko and Nori [Phys. Rev. B 85, 184506 (2012)].

  9. Stress relaxation of thermally bowed fuel pins

    International Nuclear Information System (INIS)

    Crossland, I.G.; Speight, M.V.

    1983-01-01

    The presence of cross-pin temperature gradients in nuclear reactor fuel pins produces differential thermal expansion which, in turn, causes the fuel pin to bow elastically. If the pin is restrained in any way, such thermal bowing causes the pin to be stressed. At high temperatures these stresses can relax by creep and it is shown here that this causes the pin to suffer an additional permanent deflection, so that when the cross-pin temperature difference is removed the pin remains bowed. By representing the cylindrical pin by an equivalent I-beam, the present work examines this effect when it takes place by secondary creep. Two restraint systems are considered, and it is demonstrated that the rate of relaxation depends mainly upon the creep equation, and hence the temperature, and also the magnitude of the initial stresses. (author)

  10. Defect pin behaviour in the DFR

    International Nuclear Information System (INIS)

    Sloss, W.M.; Bagley, K.Q.; Edmonds, E.; Potter, P.E.

    1979-01-01

    A program of defective fuel pin irradiations has been carried out in the DFR. This program employed fuel pins which had failed during previous irradiations (natural defects) and pins in which simulated failures (artificial defects) had been induced prior to irradiation or during an intermediate examination stage at moderate or substantial burnups. The artificial defects simulated longitudinal ruptures and were normally located at positions near the top, middle and bottom of the pin where clad temperatures were 450, 540 and 630 0 C respectively. The fuel was mixed U-Pu oxide, and fuel form, stoichiometry, clad type, pin diameter, linear rating, and burnup were among the variables examined. The defect pin tests were normally carried out in single pin or trefoil type vehicles. After irradiation all the pins were subjected to the normal nondestructive examination procedures and the visual, radiographic, gamma-scanning, and dimensional change results are presented. Several pins were destructively examined and the metallographic data are discussed

  11. MONJU fuel pin performance analysis

    International Nuclear Information System (INIS)

    Kitagawa, H.; Yamanaka, T.; Hayashi, H.

    1979-01-01

    Monju fuel pin has almost the same properties as other LMFBR fuel pins, i.e. Phenix, PFR, CRBR, but would be irradiated under severe conditions: maximum linear heat rate of 381 watt/cm, hot spot cladding temperature of 675 deg C, peak burnup of 131,000 MWd/t, peak fluence (E greater than 0.1 MeV) of 2.3 10 23 n/cm 2 . In order to understand in-core performance of Monju fuel pin, its thermal and mechanical behaviour was predicted using the fast running performance code SIMPLE. The code takes into account pellet-cladding interaction due to thermal expansion and swelling, gap conductance, structural changes of fuel pellets, fission product gas release with burnup and temperature increase, swelling and creep of fuel pellets, corrosion of cladding due to sodium flow and chemical attack by fission products, and cumulative damage of the cladding due to thermal creep

  12. Neutron radiography of fuel pins

    International Nuclear Information System (INIS)

    Jackson, C.N. Jr.; Powers, H.G.; Burgess, C.A.

    1975-01-01

    Neutron radiography performed with a reactor source has been shown to be a superior radiographic method for the examination of unirradiated mixed oxide fuel pins at the Hanford Engineering Development Laboratory. Approximately 1,700 fuel pins were contained in a sample that demonstrated the capability of the method for detecting laminations, structural flaws, fissile density variation, hydrogenous inclusions and voids in assembled fuel pins. The nature, extent, and importance of the detected conditions are substantiated by gamma autoradiography and by destructive analysis employing alpha autoradiography, electron microprobe and visual inspection. Also, a series of radiographs illustrate the response of neutron radiography as compared to low voltage and high voltage x-ray and gamma source Iridium 192 radiography. (U.S.)

  13. Measurement of X-ray spectra by PIN photodiode: comparative study

    International Nuclear Information System (INIS)

    Costa, Paulo R.; Furquim, Tania A.C.; Herdade, Silvio B.

    1996-01-01

    Two different approaches for the evaluation of diagnostic X-ray spectra are presented : one based on a semiempirical model and other based on measurements using a silicon PIN photodiode. Measured and calculated values using typical kVp and filter combinations are compared

  14. Mode of failure of LMFBR fuel pins

    International Nuclear Information System (INIS)

    Washburn, D.F.

    1975-01-01

    The objectives of the irradiation test described were to evaluate mixed-oxide fuel performance and to confirm the design adequacy of the FFTF fuel pins. After attainment of the initial objectives the irradiation of several of the original fuel pins was continued until a cladding breach occurred. The consequences of a cladding breach were evaluated by reconstituting the original 37-pin subassembly into two 19-pin subassemblies after a burnup at 50,000 MWd/MTM (5.2 a/o). The original pins were supplemented with fresh pins as necessary. Irradiation of the subassemblies was continued until a cladding breach occurred. Results are presented and discussed

  15. Improved charge collection of the buried p-i-n a-Si:H radiation detectors

    International Nuclear Information System (INIS)

    Fujieda, I.; Cho, G.; Conti, M.; Drewery, J.; Kaplan, S.N.; Perez-Mendez, V.; Qureshi, S.; Street, R.A.

    1989-09-01

    Charge collection in hydrogenated amorphous silicon (a-Si:H) radiation detectors is improved for high LET particle detection by adding thin intrinsic layers to the usual p-i-n structure. This buried p-i-n structure enables us to apply higher bias and the electric field is enhanced. When irradiated by 5.8 MeV α particles, the 5.7 μm thick buried p-i-n detector with bias 300V gives a signal size of 60,000 electrons, compared to about 20,000 electrons with the simple p-i-n detectors. The improved charge collection in the new structure is discussed. The capability of tailoring the field profile by doping a-Si:H opens a way to some interesting device structures. 17 refs., 7 figs

  16. Improved pinning regime by energetic ions using reduction of pinning potential

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Roy; Gandini, Alberto; Sawh, Ravi-Persad; Parks, Drew; Mayes, Bill

    2003-05-15

    When ion damage is used to create pinning centers, full columnar pinning centers provide the largest pinning potential, U{sub pin}, but not the greatest J{sub c} or pinned field, B{sub pin}. Some of the characteristics of columnar defects which limit J{sub c} and B{sub pin} are discussed, including reduction of percolation path, and the need for a larger number of columns of damage, for pinning, than are usually estimated. It is concluded that columnar pinning centers are limited to B{sub pin}<4 T, and also severely reduce J{sub c}. Evidence is reviewed that aligned damage, or broken-columnar pinning centers, described herein, can provide orders of magnitude higher J{sub c}, and higher pinned field, despite providing lower U{sub pin}. A pinning center morphology is discussed which utilizes multiple-in-line-damage (MILD). For, e.g., present day large grain HTS J{sub c}, obtainable by MILD pinning, is estimated to be of the order of 10{sup 6} A/cm{sup 2} at 77 K, even when crystal plane alignment and weak links are not improved. Pinned field is increased by over an order of magnitude. An experiment is proposed to confirm these observations, and to directly compare MILD to columnar pinning centers. It will also determine the optimum MILD structure. Other measurements of interest, made possible by the same data set, are described.

  17. Multicenter Study of Pin Site Infections and Skin Complications Following Pinning of Pediatric Supracondylar Humerus Fractures.

    Science.gov (United States)

    Combs, Kristen; Frick, Steven; Kiebzak, Gary

    2016-12-03

    Pediatric supracondylar humerus fractures are the most common elbow fractures in pediatric patients. Surgical fixation using pins is the primary treatment for displaced fractures. Pin site infections may follow supracondylar humerus fracture fixation; the previously reported incidence rate in the literature is 2.34%, but there is significant variability in reported incidence rates of pin site infection. This study aims to define the incidence rate and determine pre-, peri-, and postoperative factors that may contribute to pin site infection following operative reduction, pinning, and casting. A retrospective chart analysis was performed over a one-year period on patients that developed pin site infection. A cast care form was added to Nemours' electronic medical records (EMR) system (Epic Systems Corp., Verona, WI) to identify pin site infections for retrospective review. The cast care form noted any inflamed or infected pins. Patients with inflamed or infected pin sites underwent a detailed chart review. Preoperative antibiotic use, number and size of pins used, method of postoperative immobilization, pin dressings, whether postoperative immobilization was changed prior to pin removal, and length of time pins were in place was recorded. A total of 369 patients underwent operative reduction, pinning, and casting. Three patients developed a pin site infection. The pin site infection incidence rate was 3/369=0.81%. Descriptive statistics were reported for the three patients that developed pin site infections and three patients that developed pin site complications. Pin site infection development is low. Factors that may contribute to the development of pin site infection include preoperative antibiotic use, length of time pins are left in, and changing the cast prior to pin removal.

  18. Fuel pin bowing in CAGR

    International Nuclear Information System (INIS)

    Crossland, I.G.

    1982-01-01

    Some of the more important mechanisms by which pin bowing can occur in Advanced Gas Cooled Reactors are examined. These include creep relaxation of the stresses which occur when thermal bowing is restrained and asymmetric axial clad creep. The clad temperature changes which accompany such bowing are also investigated and the theoretical results briefly compared with the empirical behaviour. (author)

  19. Suspension scheme for fuel pin

    International Nuclear Information System (INIS)

    Butts, C.E.; Gray, H.C.

    1975-01-01

    A description is presented of a nuclear fuel pin suspension arrangement comprising, in combination, a rod; a first beam member connected to said rod at one end; a plurality of parallel-spaced slidable fuel support plates attached to said first beam member, the longitudinal axis of first beam member being perpendicular to the longitudinal axis of each of said fuel support plates, a first coupling means disposed along the length of the first beam member for permitting slidable fuel support plates parallel movement with respect to the longitudinal axis of said first beam member, a second coupling means located at one end of each of slidable fuel plates for slidably engaging first coupling means of first beam member, a second beam member connected to the other end of each of parallel-spaced slidable fuel support plates and providing an extension, second beam member being provided with a third coupling means disposed along the length of second beam member at one end thereof; and a plurality of fuel pins provided with a fourth coupling means located at one end of each fuel pin for slidably engaging third coupling means of second beam member to permit each fuel pin parallel movement with respect to the longitudinal axis of second beam member. (U.S.)

  20. Fabrication of detectors and transistors on high-resistivity silicon

    International Nuclear Information System (INIS)

    Holland, S.

    1988-06-01

    A new process for the fabrication of silicon p-i-n diode radiation detectors is described. The utilization of backside gettering in the fabrication process results in the actual physical removal of detrimental impurities from critical device regions. This reduces the sensitivity of detector properties to processing variables while yielding low diode reverse-leakage currents. In addition, gettering permits the use of processing temperatures compatible with integrated-circuit fabrication. P-channel MOSFETs and silicon p-i-n diodes have been fabricated simultaneously on 10 kΩ/centerreverse arrowdot/cm silicon using conventional integrated-circuit processing techniques. 25 refs., 5 figs

  1. Silicone metalization

    Energy Technology Data Exchange (ETDEWEB)

    Maghribi, Mariam N. (Livermore, CA); Krulevitch, Peter (Pleasanton, CA); Hamilton, Julie (Tracy, CA)

    2008-12-09

    A system for providing metal features on silicone comprising providing a silicone layer on a matrix and providing a metal layer on the silicone layer. An electronic apparatus can be produced by the system. The electronic apparatus comprises a silicone body and metal features on the silicone body that provide an electronic device.

  2. Large volume cryogenic silicon detectors

    International Nuclear Information System (INIS)

    Braggio, C.; Boscardin, M.; Bressi, G.; Carugno, G.; Corti, D.; Galeazzi, G.; Zorzi, N.

    2009-01-01

    We present preliminary measurements for the development of a large volume silicon detector to detect low energy and low rate energy depositions. The tested detector is a one cm-thick silicon PIN diode with an active volume of 31 cm 3 , cooled to the liquid helium temperature to obtain depletion from thermally-generated free carriers. A thorough study has been done to show that effects of charge trapping during drift disappears at a bias field value of the order of 100V/cm.

  3. Large volume cryogenic silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Braggio, C. [Dipartimento di Fisica, Universita di Padova, via Marzolo 8, 35131 Padova (Italy); Boscardin, M. [Fondazione Bruno Kessler (FBK), via Sommarive 18, I-38100 Povo (Italy); Bressi, G. [INFN sez. di Pavia, via Bassi 6, 27100 Pavia (Italy); Carugno, G.; Corti, D. [INFN sez. di Padova, via Marzolo 8, 35131 Padova (Italy); Galeazzi, G. [INFN lab. naz. Legnaro, viale dell' Universita 2, 35020 Legnaro (Italy); Zorzi, N. [Fondazione Bruno Kessler (FBK), via Sommarive 18, I-38100 Povo (Italy)

    2009-12-15

    We present preliminary measurements for the development of a large volume silicon detector to detect low energy and low rate energy depositions. The tested detector is a one cm-thick silicon PIN diode with an active volume of 31 cm{sup 3}, cooled to the liquid helium temperature to obtain depletion from thermally-generated free carriers. A thorough study has been done to show that effects of charge trapping during drift disappears at a bias field value of the order of 100V/cm.

  4. Pinning synchronization of a mobile agent network

    International Nuclear Information System (INIS)

    Wang, Lei; Sun, You-xian

    2009-01-01

    We investigate the problem of controlling a group of mobile agents in a plane in order to move them towards a desired orbit via pinning control, in which each agent is associated with a chaotic oscillator coupled with those of neighboring agents, and the pinning strategy is to have the common linear feedback acting on a small fraction of agents by random selection. We explore the effects of the pinning probability, feedback gains and agent density in the pinning synchronization of a mobile agent network under a fast-switching constraint, and perform numerical simulations for validation. In particular, we show that there exists a critical pinning density for network synchronization with an unbounded region: above the threshold, the dynamical network can be controlled by pinning; below it, anarchy prevails. And for the network with a single bounded synchronization region, pinning control has little effect as regards enhancing network synchronizability

  5. Evaluation of gamma dose effect on PIN photodiode using analytical model

    Science.gov (United States)

    Jafari, H.; Feghhi, S. A. H.; Boorboor, S.

    2018-03-01

    The PIN silicon photodiodes are widely used in the applications which may be found in radiation environment such as space mission, medical imaging and non-destructive testing. Radiation-induced damage in these devices causes to degrade the photodiode parameters. In this work, we have used new approach to evaluate gamma dose effects on a commercial PIN photodiode (BPX65) based on an analytical model. In this approach, the NIEL parameter has been calculated for gamma rays from a 60Co source by GEANT4. The radiation damage mechanisms have been considered by solving numerically the Poisson and continuity equations with the appropriate boundary conditions, parameters and physical models. Defects caused by radiation in silicon have been formulated in terms of the damage coefficient for the minority carriers' lifetime. The gamma induced degradation parameters of the silicon PIN photodiode have been analyzed in detail and the results were compared with experimental measurements and as well as the results of ATLAS semiconductor simulator to verify and parameterize the analytical model calculations. The results showed reasonable agreement between them for BPX65 silicon photodiode irradiated by 60Co gamma source at total doses up to 5 kGy under different reverse voltages.

  6. Unicortical self-drilling external fixator pins reduce thermal effects during pin insertion.

    Science.gov (United States)

    Greinwald, Markus; Varady, Patrick A; Augat, Peter

    2017-12-14

    External fixation is associated with the risk of pin loosening and pin infection potentially associated to thermal bone necrosis during pin insertion. This study aims to investigate if the use of external fixator systems with unicortical pins reduces the heat production during pin insertion compared to fixators with bicortical pins. Porcine bone specimens were employed to determine bone temperatures during insertion of fixator pins. Two thermographic cameras were used for a simultaneous temperature measurement on the bone surface (top view) and a bone cross-section (front view). Self-drilling unicortical and bicortical pins were inserted at different rotational speeds: (30-600) rpm. Maximum and mean temperatures of the emerging bone debris, bone surface and bone cross-section were analyzed. Maximum temperatures of up to 77 ± 26 °C were measured during pin insertion in the emerging debris and up to 42 ± 2 °C on the bone surface. Temperatures of the emerging debris increased with increasing rotational speeds. Bicortical pin insertion generated significantly higher temperatures at low insertion speed (30 rpm) CONCLUSION: The insertion of external fixator pins can generate a considerable amount of heat around the pins, primarily emerging from bone debris and at higher insertion speeds. Our findings suggest that unicortical, self-drilling fixator pins have a decreased risk for thermal damage, both to the surrounding tissue and to the bone itself.

  7. Spectroscopic amplifier for pin diode; Amplificador espectroscopico para diodo Pin

    Energy Technology Data Exchange (ETDEWEB)

    Alonso M, M. S.; Hernandez D, V. M.; Vega C, H. R., E-mail: bebe.luna_s@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-10-15

    The photodiode remains the basic choice for the photo-detection and is widely used in optical communications, medical diagnostics and field of corpuscular radiation. In detecting radiation it has been used for monitoring radon and its progeny and inexpensive spectrometric systems. The development of a spectroscopic amplifier for Pin diode is presented which has the following characteristics: canceler Pole-Zero (P/Z) with a time constant of 8 μs; constant gain of 57, suitable for the acquisition system; 4th integrator Gaussian order to waveform change of exponential input to semi-Gaussian output and finally a stage of baseline restorer which prevents Dc signal contribution to the next stage. The operational amplifier used is the TLE2074 of BiFET technology of Texas Instruments with 10 MHz bandwidth, 25 V/μs of slew rate and a noise floor of 17 nv/(Hz)1/2. The integrated circuit has 4 operational amplifiers and in is contained the total of spectroscopic amplifier that is the goal of electronic design. The results show like the exponential input signal is converted to semi-Gaussian, modifying only the amplitude according to the specifications in the design. The total system is formed by the detector, which is the Pin diode, a sensitive preamplifier to the load, the spectroscopic amplifier that is what is presented and finally a pulse height analyzer (Mca) which is where the spectrum is shown. (Author)

  8. Pin Wire Coating Trip Report

    International Nuclear Information System (INIS)

    Spellman, G P

    2004-01-01

    A meeting to discuss the current pin wire coating problems was held at the Reynolds plant in Los Angeles on 2MAR04. The attendance list for Reynolds personnel is attached. there was an initial presentation which gave a brief history and the current status of pin wire coating at Reynolds. There was a presentation by Lori Primus on the requirements and issues for the coating. There was a presentation by Jim Smith of LANL on the chemistry and to some extent process development done to date. There was a long session covering what steps should be taken in the short term and, to a lesser extent, the long term. The coating currently being used is a blend of two polymers, polyethersulfone and polyparabanic acid (PPA) and some TiO2 filler. This system was accepted and put into production when the pin wire coating was outsourced to another company in 1974. When that company no longer was interested, the wire coating was brought in-house to Reynolds. At that time polyparabanic acid was actually a commercial product available from Exxon under the trade name Tradlon. However, it appears that the material used at Reynolds was synthesized locally. Also, it appears that a single large batch was synthesized in that time period and used up to 1997 when the supply ran out. The reason for the inclusion of TiO2 is not known although it does act as a rheological thickener. However, a more controlled thickening can be obtained with materials such as fumed silica. This material would have less likelihood of causing point imperfections in the coatings. Also, the mixing technique being used for all stages of the process is a relatively low shear ball mill process and the author recommends a high shear process such as a three roll paint mill, at least for the final mixing. Since solvent is added to the powder at Reynolds, it may be that they need to have the paint mill there

  9. Transient survivability of LMR oxide fuel pins

    International Nuclear Information System (INIS)

    Weber, E.T.; Pitner, A.L.; Bard, F.E.; Culley, G.E.; Hunter, C.W.

    1986-01-01

    Fuel pin integrity during transient events must be assessed for both the core design and safety analysis phases of a reactor project. A significant increase in the experience related to limits of integrity for oxide fuel pins in transient overpower events has been realized from testing of fuel pins irradiated in FFTF and PFR. Fourteen FFTF irradiated fuel pins were tested in TREAT, representing a range of burnups, overpower ramp rates and maximum overpower conditions. Results of these tests along with similar testing in the PFR/TREAT program, provide a demonstration of significant safety margins for oxide fuel pins. Useful information applied in analytical extrapolation of fuel pin test data have been developed from laboratory transient tests on irradiated fuel cladding (FCTT) and on unirradiated fuel pellet deformation. These refinements in oxide fuel transient performance are being applied in assessment of transient capabilities of long lifetime fuel designs using ferritic cladding

  10. Cesium migration in LMFBR fuel pins

    International Nuclear Information System (INIS)

    Karnesky, R.A.; Jost, J.W.; Stone, I.Z.

    1978-10-01

    The factors affecting the axial migration of cesium in mixed oxide fuel pins and the effects of cesium migration on fuel pin performance are examined. The development and application of a correlated model which will predict the occurrence of cesium migration in a mixed oxide (75 w/o UO 2 + 25 w/o PuO 2 ) fuel pins over a wide range of fabrication and irradiation conditions are described

  11. FFTF fuel pin design bases and performance

    International Nuclear Information System (INIS)

    Cox, C.M.; Hanson, J.E.; Roake, W.E.; Slember, R.J.; Weber, C.E.; Millunzi, A.C.

    1975-04-01

    The FFTF fuel pin was conservatively designed to meet thermal and structural performance requirements in the categories normal operation, upset events, emergency events, and hypothetical, faulted events. The fuel pin operating limits consistent with these requirements were developed from a strong fuel pin irradiation testing program scoped to define the performance capability under relevant steady state and transient conditions. Comparison of the results of the irradiation testing program with design requirements indicates that the FFTF fuel pin can exceed its goal burnup of 80,000 MWd/MTM. (U.S.)

  12. Integral Fast Reactor fuel pin processor

    International Nuclear Information System (INIS)

    Levinskas, D.

    1993-01-01

    This report discusses the pin processor which receives metal alloy pins cast from recycled Integral Fast Reactor (IFR) fuel and prepares them for assembly into new IFR fuel elements. Either full length as-cast or precut pins are fed to the machine from a magazine, cut if necessary, and measured for length, weight, diameter and deviation from straightness. Accepted pins are loaded into cladding jackets located in a magazine, while rejects and cutting scraps are separated into trays. The magazines, trays, and the individual modules that perform the different machine functions are assembled and removed using remote manipulators and master-slaves

  13. Magnetic pinning in superconductor-ferromagnet multilayers

    International Nuclear Information System (INIS)

    Bulaevskii, L. N.; Chudnovsky, E. M.; Maley, M. P.

    2000-01-01

    We argue that superconductor/ferromagnet multilayers of nanoscale period should exhibit strong pinning of vortices by the magnetic domain structure in magnetic fields below the coercive field when ferromagnetic layers exhibit strong perpendicular magnetic anisotropy. The estimated maximum magnetic pinning energy for single vortex in such a system is about 100 times larger than the pinning energy by columnar defects. This pinning energy may provide critical currents as high as 10 6 -10 7 A/cm 2 at high temperatures (but not very close to T c ) at least in magnetic fields below 0.1 T. (c) 2000 American Institute of Physics

  14. Magnetic pinning in superconductor-ferromagnet multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Bulaevskii, L. N. [Department of Physics and Astronomy, CUNY Lehman College 250 Bedford Park Boulevard West, Bronx, New York 10468-1589 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Chudnovsky, E. M. [Department of Physics and Astronomy, CUNY Lehman College, 250 Bedford Park Boulevard West, Bronx, New York 10468-1589 (United States); Maley, M. P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2000-05-01

    We argue that superconductor/ferromagnet multilayers of nanoscale period should exhibit strong pinning of vortices by the magnetic domain structure in magnetic fields below the coercive field when ferromagnetic layers exhibit strong perpendicular magnetic anisotropy. The estimated maximum magnetic pinning energy for single vortex in such a system is about 100 times larger than the pinning energy by columnar defects. This pinning energy may provide critical currents as high as 10{sup 6}-10{sup 7} A/cm{sup 2} at high temperatures (but not very close to T{sub c}) at least in magnetic fields below 0.1 T. (c) 2000 American Institute of Physics.

  15. Fabrication of FFTF fuel pin wire wrap

    International Nuclear Information System (INIS)

    Epperson, E.M.

    1980-06-01

    Lateral spacing between FFTF fuel pins is required to provide a passageway for the sodium coolant to flow over each pin to remove heat generated by the fission process. This spacing is provided by wrapping each fuel pin with type 316 stainless steel wire. This wire has a 1.435mm (0.0565 in.) to 1.448mm (0.0570 in.) diameter, contains 17 +- 2% cold work and was fabricated and tested to exacting RDT Standards. About 500 kg (1100 lbs) or 39 Km (24 miles) of fuel pin wrap wire is used in each core loading. Fabrication procedures and quality assurance tests are described

  16. Analysis of IV characteristics of solar cells made of hydrogenated amorphous, polymorphous and microcrystalline silicon

    International Nuclear Information System (INIS)

    Hamadeh, H.

    2009-03-01

    The IV characteristics of pin solar cells made of amorphous, polymorphous and microcrystalline silicon were investigated. The temperature dependence was measured in the temperature range between 150 K and 395 K. This range covers the most terrestrial applications condition. Using simplex procedure, the IV parameter of the cells were deduce using line fitting. It has been shown that polymorphous silicon shows electrical properties that are close to properties of microcrystalline silicon but as it is well known, polymorphous silicon shows higher absorption similar to amorphous silicon. The polymorphous silicon solar cells showed higher efficiencies, lower shunting and higher filling factors. In the above mentioned temperature range, polymorphous silicon is the better material for the manufacturing of thin film hydrogenated silicon pin solar cells. More investigations concerning the structural properties are necessary to make stronger conclusions in regards to the stability of the material, what we hope to do in the future. (author)

  17. Spectroscopic amplifier for pin diode

    International Nuclear Information System (INIS)

    Alonso M, M. S.; Hernandez D, V. M.; Vega C, H. R.

    2014-10-01

    The photodiode remains the basic choice for the photo-detection and is widely used in optical communications, medical diagnostics and field of corpuscular radiation. In detecting radiation it has been used for monitoring radon and its progeny and inexpensive spectrometric systems. The development of a spectroscopic amplifier for Pin diode is presented which has the following characteristics: canceler Pole-Zero (P/Z) with a time constant of 8 μs; constant gain of 57, suitable for the acquisition system; 4th integrator Gaussian order to waveform change of exponential input to semi-Gaussian output and finally a stage of baseline restorer which prevents Dc signal contribution to the next stage. The operational amplifier used is the TLE2074 of BiFET technology of Texas Instruments with 10 MHz bandwidth, 25 V/μs of slew rate and a noise floor of 17 nv/(Hz)1/2. The integrated circuit has 4 operational amplifiers and in is contained the total of spectroscopic amplifier that is the goal of electronic design. The results show like the exponential input signal is converted to semi-Gaussian, modifying only the amplitude according to the specifications in the design. The total system is formed by the detector, which is the Pin diode, a sensitive preamplifier to the load, the spectroscopic amplifier that is what is presented and finally a pulse height analyzer (Mca) which is where the spectrum is shown. (Author)

  18. Reduction of halo pin site morbidity with a new pin care regimen.

    Science.gov (United States)

    Kazi, Hussain Anthony; de Matas, Marcus; Pillay, Robin

    2013-06-01

    A retrospective analysis of halo device associated morbidity over a 4-year period. To assess the impact of a new pin care regimen on halo pin site related morbidity. Halo orthosis treatment still has a role in cervical spine pathology, despite increasing possibilities of open surgical treatment. Published figures for pin site infection range from 12% to 22% with pin loosening from 7% to 50%. We assessed the outcome of a new pin care regimen on morbidity associated with halo spinal orthoses, using a retrospective cohort study from 2001 to 2004. In the last two years, our pin care regimen was changed. This involved pin site care using chlorhexidene & regular torque checking as part of a standard protocol. Previously, povidone iodine was used as skin preparation in theatre, followed by regular sterile saline cleansing when pin sites became encrusted with blood. There were 37 patients in the series, the median age was 49 (range, 22-83) and 20 patients were male. The overall infection rate prior to the new pin care protocol was 30% (n=6) and after the introduction, it dropped to 5.9% (n=1). This difference was statistically significant (p<0.05). Pin loosening occurred in one patient in the group prior to the formal pin care protocol (3%) and none thereafter. Reduced morbidity from halo use can be achieved with a modified pin cleansing and tightening regimen.

  19. Phosphorylation of conserved PIN motifs directs Arabidopsis PIN1 polarity and auxin transport

    NARCIS (Netherlands)

    Huang, F.; Kemel Zago, M.; Abas, L.; van Marion, A.; Galván-Ampudia, C.S.; Offringa, R.

    2010-01-01

    Polar cell-to-cell transport of auxin by plasma membrane-localized PIN-FORMED (PIN) auxin efflux carriers generates auxin gradients that provide positional information for various plant developmental processes. The apical-basal polar localization of the PIN proteins that determines the direction of

  20. Synchronizability on complex networks via pinning control

    Indian Academy of Sciences (India)

    Keywords. Complex network; the pinning synchronization; synchronizability. ... The findings reveal the relationship between the decreasing speed of maximum eigenvalue sequence of the principal submatrices for coupling matrix and the synchronizability on complex networks via pinning control. We discuss the ...

  1. Breached-pin testing in the US

    International Nuclear Information System (INIS)

    Mahagin, D.E.; Lambert, J.D.B.

    1981-04-01

    Experience gained at EBR-II by the late 1970's from a significant number of failures in experimental fuel-pin irradiations forms the basis of a program directed towards the characterization of breached pins. The questions to be answered and the issues raised by further testing are discussed

  2. TACO: fuel pin performance analysis

    International Nuclear Information System (INIS)

    Stoudt, R.H.; Buchanan, D.T.; Buescher, B.J.; Losh, L.L.; Wilson, H.W.; Henningson, P.J.

    1977-08-01

    The thermal performance of fuel in an LWR during its operational lifetime must be described for LOCA analysis as well as for other safety analyses. The determination of stored energy in the LOCA analysis, for example, requires a conservative fuel pin thermal performance model that is capable of calculating fuel and cladding behavior, including the gap conductance between the fuel and cladding, as a function of burnup. The determination of parameters that affect the fuel and cladding performance, such as fuel densification, fission gas release, cladding dimensional changes, fuel relocation, and thermal expansion, should be accounted for in the model. Babcock and Wilcox (B and W) has submitted a topical report, BAW-10087P, December 1975, which describes their thermal performance model TACO. A summary of the elements that comprise the TACO model and an evaluation are presented

  3. Incommensurate pinning mechanism in KCP

    International Nuclear Information System (INIS)

    Apostol, M.; Baldea, I.

    1984-07-01

    A new pinning mechanism (termed incommensurate) is put forward for K 2 Pt(CN) 4 Brsub(0.3)x3.2H 2 O(KCP) based on the Q-quasi-modulated distribution of the bromine anions (Br-bar) along the chain axis (Q/2 being the Fermi momentum reduced to the first Brillouin zone). The different origins of the direct current (d.c.) thermally-activated gap and optical gap are thereby explained. The spectrum of the collective excitations (amplitudons and phasons) and the dielectric function are calculated for the charge density wave (CDW) state. Fair agreement is obtained with the optical and neutron scattering data. (author)

  4. Pinning impulsive control algorithms for complex network

    International Nuclear Information System (INIS)

    Sun, Wen; Lü, Jinhu; Chen, Shihua; Yu, Xinghuo

    2014-01-01

    In this paper, we further investigate the synchronization of complex dynamical network via pinning control in which a selection of nodes are controlled at discrete times. Different from most existing work, the pinning control algorithms utilize only the impulsive signals at discrete time instants, which may greatly improve the communication channel efficiency and reduce control cost. Two classes of algorithms are designed, one for strongly connected complex network and another for non-strongly connected complex network. It is suggested that in the strongly connected network with suitable coupling strength, a single controller at any one of the network's nodes can always pin the network to its homogeneous solution. In the non-strongly connected case, the location and minimum number of nodes needed to pin the network are determined by the Frobenius normal form of the coupling matrix. In addition, the coupling matrix is not necessarily symmetric or irreducible. Illustrative examples are then given to validate the proposed pinning impulsive control algorithms

  5. Resistance projection welding small pins in vacuum tube feedthrough assembly

    International Nuclear Information System (INIS)

    Kuncz, F. Jr.

    1980-01-01

    Resistance projection welding of two stainless steel pins to a cup is successfully accomplished by specially designed electrodes and by forming domes on the pin ends. Details of electrode and pin construction are given, as well as welding parameters

  6. High energy x-ray radiography and computed tomography of bridge pins

    International Nuclear Information System (INIS)

    Green, R E; Logan, C M; Martz, H E; Updike, E; Waters, A M

    1999-01-01

    Bridge pins were used in the hanger assemblies for some multi-span steel bridges built prior to the 1980's, and are sometimes considered fracture critical elements of a bridge. During a test on a bridge conducted by the Federal Highway Administration (FHWA), ultrasonic field inspection results indicated that at least two pins contained cracks. Several pins were removed and selected for further examination. This provided an excellent opportunity to learn more about these pins and the application of x-ray systems at Lawrence Livermore National Laboratory (LLNL), as well as to learn more about the application of different detectors recently obtained by LLNL. Digital radiographs and computed tomography (CT) were used to characterize the bridge pins, using a LINAC x-ray source with a 9-MV bremsstrahlung spectrum. We will describe the performance of two different digital radiographic detectors. One is a detector system frequently used at LLNL consisting of a scintillator glass optically coupled to a CCD camera. The other detector is a new amorphous silicon detector recently acquired by LLNL

  7. Pin fin compliant heat sink with enhanced flexibility

    Science.gov (United States)

    Schultz, Mark D.

    2018-04-10

    Heat sinks and methods of using the same include a top and bottom plate, at least one of which has a plurality of pin contacts flexibly connected to one another, where the plurality of pin contacts have vertical and lateral flexibility with respect to one another; and pin slice layers, each having multiple pin slices, arranged vertically between the top and bottom plates such that the plurality of pin slices form substantially vertical pins connecting the top and bottom plates.

  8. Silicon detectors

    International Nuclear Information System (INIS)

    Klanner, R.

    1984-08-01

    The status and recent progress of silicon detectors for high energy physics is reviewed. Emphasis is put on detectors with high spatial resolution and the use of silicon detectors in calorimeters. (orig.)

  9. Cesium chemistry in GCFR fuel pins

    International Nuclear Information System (INIS)

    Fee, D.C.; Johnson, C.E.

    1979-01-01

    The fuel rod design for the Gas Cooled Fast-Breeder Reactor (GCFR) is similar to that employed for the Liquid Metal Fast Breeder Reactor (LMFBR) with the exception of the unique features inherent to the use of helium as the coolant. These unique design features include the use of (1) vented and pressure-equalized fuel rods, and (2) ribbed cladding along 75% of the fuel section. The former design feature enables reduction in cladding thickness and prevention of possible creep collapse of the cladding due to the high coolant pressure (8.5 MPa). The latter design feature brings about improved heat transfer characteristics. Each GCFR fuel rod is vented to a manifold whereby gaseous fission products diffusing out of the fuel pin are retained on charcoal traps. As a result, the internal pressure of a GCFR fuel pin does not increase during irradiation. In addition, the venting system also maintains the pressure within the fuel pin slightly below (0.3 to 0.5 MPa) the coolant pressure outside the fuel pin. Consequently, should a breach occur in the cladding, helium flows into the breached fuel pin thereby minimizing fission product contamination of the coolant. These desirable aspects of a GCFR fuel pin can be maintained only as long as axial gas transport paths are available and operating within the fuel pin

  10. Vortex lattice melting, pinning and kinetics

    International Nuclear Information System (INIS)

    Doniach, S.; Ryu, S.; Kapitulnik, A.

    1994-01-01

    The phenomenology of the high T c superconductors is discussed both at the level of the thermodynamics of melting of the Abrikosov flux lattice and in terms of the melting and kinetics of the flux lattice for a pinned system. The authors review results on 3D melting obtained by a Monte Carlo simulation approach in which the 2D open-quotes pancakeclose quotes vortices are treated as statistical variables. The authors discuss pinning in the context of the strong pinning regime in which the vortex density given in terms of the applied field B is small compared to that represented by an effective field B pin measuring the pinning center density. The authors introduce a new criterion for the unfreezing of a vortex glass on increase of magnetic field or temperature, in the strong pinning, small field unit. The authors model this limit in terms of a single flux line interacting with a columnar pin. This model is studied both analytically and by computer simulation. By applying a tilt potential, the authors study the kinetics of the vortex motion in an external current and show that the resulting current-voltage characteristic follows a basic vortex glass-like scaling relation in the vicinity of the depinning transition

  11. Computer simulation of vortex pinning in type II superconductors. II. Random point pins

    International Nuclear Information System (INIS)

    Brandt, E.H.

    1983-01-01

    Pinning of vortices in a type II superconductor by randomly positioned identical point pins is simulated using the two-dimensional method described in a previous paper (Part I). The system is characterized by the vortex and pin numbers (N/sub v/, N/sub p/), the vortex and pin interaction ranges (R/sub v/, R/sub p/), and the amplitude of the pin potential A/sub p/. The computation is performed for many cases: dilute or dense, sharp or soft, attractive or repulsive, weak or strong pins, and ideal or amorphous vortex lattice. The total pinning force F as a function of the mean vortex displacment X increases first linearly (over a distance usually much smaller than the vortex spacing and than R/sub p/) and then saturates, fluctuating about its averaging F-bar. We interpret F-bar as the maximum pinning force j/sub c/B of a large specimen. For weak pins the prediction of Larkin and Ovchinnikov for two-dimensional collective pinning is confirmed: F-bar = const. iW/R/sub p/c 66 , where W-bar is the mean square pinning force and c 66 is the shear modulus of the vortex lattice. If the initial vortex lattice is chosen highly defective (''amorphous'') the constant is 1.3--3 times larger than for the ideal triangular lattice. This finding may explain the often observed ''history effect.'' The function F-bar(A/sub p/) exhibits a jump, which for dilute, sharp, attractive pins occurs close to the ''threshold value'' predicted for isolated pins by Labusch. This jump reflects the onset of plastic deformation of the vortex lattice, and in some cases of vortex trapping, but is not a genuine threshold

  12. Electro-optical fuel pin identification system

    International Nuclear Information System (INIS)

    Kirchner, T.L.

    1978-09-01

    A prototype Electro-Optical Fuel Pin Identification System referred to as the Fuel Pin Identification System (FPIS) has been developed by the Hanford Engineering Development Laboratory (HEDL) in support of the Fast Flux Test Facility (FFTF) presently under construction at HEDL. The system is designed to remotely read an alpha-numeric identification number that is roll stamped on the top of the fuel pin end cap. The prototype FPIS consists of four major subassemblies: optical read head, digital compression electronics, video display, and line printer

  13. Flux pinning characteristics of YBCO coated conductor

    International Nuclear Information System (INIS)

    Matsushita, T.; Watanabe, T.; Fukumoto, Y.; Yamauchi, K.; Kiuchi, M.; Otabe, E.S.; Kiss, T.; Watanabe, T.; Miyata, S.; Ibi, A.; Muroga, T.; Yamada, Y.; Shiohara, Y.

    2005-01-01

    Flux pinning properties of PLD-processed YBCO coated conductors deposited on IBAD substrate are investigated. The thickness of YBCO layer is changed in the range of 0.27-1.0 μm. The thickness dependence of critical current density, n-value and irreversibility field are measured in a wide range of magnetic field. The results are compared with the theoretical flux creep-flow model. It is found that these pinning properties are strongly influenced by the thickness as well as the pinning strength. Optimum condition for high field application of this superconductor is discussed

  14. Pinning and creep in superconductors

    International Nuclear Information System (INIS)

    Ovchinnikov, Yu.N.

    1994-01-01

    All superconductors can be separated into two large groups: type I and type II. The behaviour of these two groups in a magnetic field is quite different. The superconductors of type I, in a strong magnetic field, enter the intermediate state. Phenomenological picture of this state was given by Landau. The type II superconductors, in strong magnetic fields, form the mixed state (or Shubnikov phase). The microscopic picture of the mixed state was given by Abrikosov on the basis of Ginzburg-Landau equations. In ideal homogeneous superconductors the free energy is not changed if all the vortex structure is shifted on some distance u. The transport current will be proportional, therefore, to the electric field E. All the real superconductors, however, are inhomogeneous. Inhomogeneities interact with vortex lattice and pin it. In this new state the transport current below some critical value does not lead to the motion of the flux lattice and to the energy dissipation. The value of critical current strongly depends on the type of inhomogeneities, on the value of magnetic field and on temperature. In new layered superconductors, the critical current depends also on the orientation of the magnetic field B with respect to the layer planes. Temperature and quantum fluctuations lead to the transition between different metastable states in superconductors with current. As a result, the vortex lattice slowly moves (creep phenomenon). Below we will briefly discuss all these phenomena. (orig.)

  15. Silicon radiation detector

    International Nuclear Information System (INIS)

    Benc, I.; Kerhart, J.; Kopecky, J.; Krca, P.; Veverka, V.; Weidner, M.; Weinova, H.

    1992-01-01

    The silicon radiation detector, which is designed for the detection of electrons with energies above 500 eV and of radiation within the region of 200 to 1100 nm, comprises a PIN or PNN + type photodiode. The active acceptor photodiode is formed by a detector surface of shallow acceptor diffusion surrounded by a collector band of deep acceptor diffusion. The detector surface of shallow P-type diffusion with an acceptor concentration of 10 15 to 10 17 atoms/cm 3 reaches a depth of 40 to 100 nm. One sixth to one eighth of the collector band width is overlapped by the P + collector band at a width of 150 to 300 μm with an acceptor concentration of 10 20 to 10 21 atoms/cm 3 down a depth of 0.5 to 3 μm. This band is covered with a conductive layer, of NiCr for instance. (Z.S.)

  16. Vortex pinning by point defect in superconductors

    International Nuclear Information System (INIS)

    Liao Hongyin; Zhou Shiping; Du Haochen

    2003-01-01

    We apply the periodic time-dependent Ginzburg-Landau model to study vortex distribution in type-II superconductors with a point-like defect and square pinning array. A defect site will pin vortices, and a periodic pinning array with right geometric parameters, which can be any form designed in advance, shapes the vortex pattern as external magnetic field varies. The maximum length over which an attractive interaction between a pinning centre and a vortex extends is estimated to be about 6.0ξ. We also derive spatial distribution expressions for the order parameter, vector potential, magnetic field and supercurrent induced by a point defect. Theoretical results and numerical simulations are compared with each other and they are consistent

  17. Pinning Synchronization of Switched Complex Dynamical Networks

    Directory of Open Access Journals (Sweden)

    Liming Du

    2015-01-01

    Full Text Available Network topology and node dynamics play a key role in forming synchronization of complex networks. Unfortunately there is no effective synchronization criterion for pinning synchronization of complex dynamical networks with switching topology. In this paper, pinning synchronization of complex dynamical networks with switching topology is studied. Two basic problems are considered: one is pinning synchronization of switched complex networks under arbitrary switching; the other is pinning synchronization of switched complex networks by design of switching when synchronization cannot achieved by using any individual connection topology alone. For the two problems, common Lyapunov function method and single Lyapunov function method are used respectively, some global synchronization criteria are proposed and the designed switching law is given. Finally, simulation results verify the validity of the results.

  18. Nuclear fuel pin controlled failure device

    International Nuclear Information System (INIS)

    Schlenker, L.D.

    1975-01-01

    Each fuel pin of a fuel assembly for a water-cooled nuclear reactor is provided with means for rupturing the cladding tube at a predetermined location if an abnormal increase in pressure of the gases present occurs due to a loss-of-coolant accident. Preferably all such rupture means are oriented to minimize the hydraulic resistance to the flow of emergency core coolant such as all rupture means pointing in the same direction. Rupture means may be disposed at different elevations in adjacent fuel pins and, further, fuel pins may be provided with two or more rupture means, one of which is in the upper portion of the fuel pin. Rupture means are mechanical as by providing a locally weakened condition of a controlled nature in the cladding. (U.S.)

  19. Ultrasonic inspections of fuel alignment pins

    International Nuclear Information System (INIS)

    Rathgeb, W.; Schmid, R.

    1994-01-01

    As a remedy to the practical problem of defects in fuel alignment pins made of Inconel X750, an inspection technique has been developed which fully meets the requirements of detecting defects. The newly used fuel alignment pins made of austenite are easy to test and therefore satisfy the necessity of further inspections.For the fuel alignment pins of the upper core structure a safe and fast inspection technique was made available. The inspection sensitivity is high and it is possible to give quantitative directions concerning defect orientation and depth. After the required inspections had been concluded in 1989, a total of 18 inspections were carried out in various national and international nuclear power plants in the following years. During this time more than 6000 fuel alignment pines were examined.For the fuel alignment pins the inspection technique provided could increase the understanding of the defect process. This technique contributed to the development of an adaptive and economical repair strategy. ((orig.))

  20. Suppression of irradiation effects in gold-doped silicon detectors

    International Nuclear Information System (INIS)

    McPherson, M.; Sloan, T.; Jones, B.K.

    1997-01-01

    Two sets of silicon detectors were irradiated with 1 MeV neutrons to different fluences and then characterized. The first batch were ordinary p-i-n photodiodes fabricated from high-resistivity (400 Ω cm) silicon, while the second batch were gold-doped powder diodes fabricated from silicon material initially of low resistivity (20 Ω cm). The increase in reverse leakage current after irradiation was found to be more in the former case than in the latter. The fluence dependence of the capacitance was much more pronounced in the p-i-n diodes than in the gold-doped diodes. Furthermore, photo current generation by optical means was less in the gold doped devices. All these results suggest that gold doping in silicon somewhat suppresses the effects of neutron irradiation. (author)

  1. Application of PIN diodes in Physics Research

    International Nuclear Information System (INIS)

    Ramirez-Jimenez, F. J.; Mondragon-Contreras, L.; Cruz-Estrada, P.

    2006-01-01

    A review of the application of PIN diodes as radiation detectors in different fields of Physics research is presented. The development and research in semiconductor technology, the use of PIN diodes in particle counting, X-and γ-ray spectroscopy, medical applications and charged particle spectroscopy are considered. Emphasis is made in the activities realized in the different research and development Mexican institutions dealing with this kind of radiation detectors

  2. IMp: The customizable LEGO® Pinned Insect Manipulator

    Directory of Open Access Journals (Sweden)

    Steen Dupont

    2015-02-01

    Full Text Available We present a pinned insect manipulator (IMp constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble.

  3. IMp: The customizable LEGO® Pinned Insect Manipulator

    Science.gov (United States)

    Dupont, Steen; Price, Benjamin; Blagoderov, Vladimir

    2015-01-01

    Abstract We present a pinned insect manipulator (IMp) constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble. PMID:25685035

  4. Anisotropic flux pinning in high Tc superconductors

    International Nuclear Information System (INIS)

    Kolesnik, S.; Igalson, J.; Skoskiewicz, T.; Szymczak, R.; Baran, M.; Pytel, K.; Pytel, B.

    1995-01-01

    In this paper we present a comparison of the results of FC magnetization measurements on several Pb-Sr-(Y,Ca)-Cu-O crystals representing various levels of flux pinning. The pinning centers in our crystals have been set up during the crystal growth process or introduced by neutron irradiation. Some possible explanations of the observed effects, including surface barrier, flux-center distribution and sample-shape effects, are discussed. ((orig.))

  5. Investigation on macroscopic cross section model for BWR pin-by-pin core analysis - 118

    International Nuclear Information System (INIS)

    Fujita, T.; Tada, K.; Yamamoto, A.; Yamane, Y.; Kosaka, S.; Hirano, G.

    2010-01-01

    A cross section model used in the pin-by-pin core analysis for BWR is investigated. In the pin-by-pin core calculation method, pin-cell averaged cross sections are calculated for many combinations of state and history variables that have influences on the cross section and are tabulated prior to the core calculations. Variation of a cross section in a core simulator is classified into two different types, i.e., the instantaneous effect and the history effect. The instantaneous effect is incorporated by the variation of cross section which is caused by the instantaneous change of state variables. For this effect, the exposure, the void fraction, the fuel temperature, the moderator temperature and the control rod are used as indexes. The history effect is the cumulative effect of state variables. We treat this effect with a unified approach using the spectral history. To confirm accuracy of the cross section model, the pin-by-pin fission rate distribution and the k-infinity of fuel assembly which are obtained with the tabulated and the reference cross sections are compared. For the instantaneous effect, the present cross section model well reproduces the reference results for all off-nominal conditions. For the history effect, however, considerable differences both on the pin-by-pin fission rate distribution and the k-infinity are observed at high exposure points. (authors)

  6. A macroscopic cross-section model for BWR pin-by-pin core analysis

    International Nuclear Information System (INIS)

    Fujita, Tatsuya; Endo, Tomohiro; Yamamoto, Akio

    2014-01-01

    A macroscopic cross-section model used in boiling water reactor (BWR) pin-by-pin core analysis is studied. In the pin-by-pin core calculation method, pin-cell averaged cross sections are calculated for many combinations of core state and depletion history variables and are tabulated prior to core calculations. Variations of cross sections in a core simulator are caused by two different phenomena (i.e. instantaneous and history effects). We treat them through the core state variables and the exposure-averaged core state variables, respectively. Furthermore, the cross-term effect among the core state and the depletion history variables is considered. In order to confirm the calculation accuracy and discuss the treatment of the cross-term effect, the k-infinity and the pin-by-pin fission rate distributions in a single fuel assembly geometry are compared. Some cross-term effects could be negligible since the impacts of them are sufficiently small. However, the cross-term effects among the control rod history (or the void history) and other variables have large impacts; thus, the consideration of them is crucial. The present macroscopic cross-section model, which considers such dominant cross-term effects, well reproduces the reference results and can be a candidate in practical applications for BWR pin-by-pin core analysis on the normal operations. (author)

  7. Thermo-Optic Characterization of Silicon Nitride Resonators for Cryogenic Photonic Circuits

    NARCIS (Netherlands)

    Elshaari, A.W.A.; Esmaeil Zadeh, I.; Jöns, K.D.; Zwiller, Val

    2016-01-01

    <p>In this paper, we characterize the Thermo-optic properties of silicon nitride ring resonators between 18 and 300 K. The Thermo-optic coefficients of the silicon nitride core and the oxide cladding are measured by studying the temperature dependence of the resonance wavelengths. The resonant modes

  8. Improved pinning by multiple in-line damage

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Roy [Beam Particle Dynamics Laboratories, University of Houston, Houston, TX 77204-5005 (United States); Sawh, Ravi-Persad [Beam Particle Dynamics Laboratories, University of Houston, Houston, TX 77204-5005 (United States); Gandini, Alberto [Beam Particle Dynamics Laboratories, University of Houston, Houston, TX 77204-5005 (United States); Parks, Drew [Beam Particle Dynamics Laboratories, University of Houston, Houston, TX 77204-5005 (United States)

    2005-02-01

    Columnar pinning centres provide the largest pinning potential, U{sub pin}, but not the greatest J{sub c} or pinnable field, B{sub pin}. Characteristics of ion-generated columnar defects which limit J{sub c} and B{sub pin} are discussed, including reduction of the percolation path, and the need for a larger number of columns of damage, for pinning, than are usually estimated. It is concluded that columnar pinning centres limit B{sub pin} to less than 4 T, and also severely reduce J{sub c}. The goal of maximizing U{sub pin}, via columnar centres, appears to have obscured a more rewarding approach and resulted in neglect of a large regime of ion interactions. Evidence is reviewed that multiple in-line damage (MILD), described herein, can provide orders of magnitude higher J{sub c} and B{sub pin}, despite providing lower U{sub pin}. The MILD pinning centre morphology is discussed, and it is estimated that for present-day large grain high T{sub c} superconductors, a J{sub c} value of {approx}10{sup 6}Acm{sup -2} is obtainable at 77 K, even when crystal plane alignment and weak links are not improved. In addition, the pinned field is increased by over an order of magnitude. An experiment is proposed to confirm these calculations, directly compare MILD pinning to continuous columnar pinning, and determine the optimum MILD structure. Applications of MILD pinning are discussed.

  9. Gamma ray spectroscopy and timing using LSO and PIN photodiodes

    International Nuclear Information System (INIS)

    Moses, W.W.; Derenzo, S.E.; Melcher, C.L.; Manente, R.A.

    1994-11-01

    The high density, high light output, and short decay time of LSO (lutetium orthosilicate, Lu 2 SiO 5 :Ce) make it an attractive scintillator for gamma ray spectroscopy. The low cost, small size, high quantum efficiency, and ruggedness of silicon photodiodes make them attractive photodetectors for this same application, although their high noise (Compared to a photomultiplier tube) reduces their appeal. In this work the authors measure the gamma ray energy resolution, timing accuracy, and conversion factor from gamma energy to number of electron-hole pairs produced with a 3 x 3 x 22 mm 3 LSO scintillator crystal read out with a 3 x 3 mm 2 silicon PIN photodiode. When the detector is excited with 511 keV photons, a photopeak centered at 1,940 e - with 149 keV fwhm is observed and a timing signal with 35 ns fwhm jitter is produced. When the detector is excited with 1,275 keV photons, a photopeak centered at 4,910 e - with 149 keV fwhm is observed and a timing signal with 25 ns fwhm jitter is produced. While these performance measures are inferior to those obtained with photomultiplier tubes, they are acceptable for some applications

  10. Heterogeneous neutron-leakage model for PWR pin-by-pin calculation

    International Nuclear Information System (INIS)

    Li, Yunzhao; Zhang, Bin; Wu, Hongchun; Shen, Wei

    2017-01-01

    Highlights: •The derivation of the formula of the leakage model is introduced. This paper evaluates homogeneous and heterogeneous leakage models used in PWR pin-by-pin calculation. •The implements of homogeneous and heterogeneous leakage models used in pin-cell homogenization of the lattice calculation are studied. A consistent method of cooperation between the heterogeneous leakage model and the pin-cell homogenization theory is proposed. •Considering the computational cost, a new buckling search scheme is proposed to reach the convergence faster. The computational cost of the newly proposed neutron balance scheme is much less than the power-method scheme and the linear-interpolation scheme. -- Abstract: When assembly calculation is performed with the reflective boundary condition, a leakage model is usually required in the lattice code. The previous studies show that the homogeneous leakage model works effectively for the assembly homogenization. However, it becomes different and unsettled for the pin-cell homogenization. Thus, this paper evaluates homogeneous and heterogeneous leakage models used in pin-by-pin calculation. The implements of homogeneous and heterogeneous leakage models used in pin-cell homogenization of the lattice calculation are studied. A consistent method of cooperation between the heterogeneous leakage model and the pin-cell homogenization theory is proposed. Considering the computational cost, a new buckling search scheme is proposed to reach the convergence faster. For practical reactor-core applications, the diffusion coefficients determined by the transport cross-section or by the leakage model are compared with each other to determine which one is more accurate for the Pressurized Water Reactor pin-by-pin calculation. Numerical results have demonstrated that the heterogeneous leakage model together with the diffusion coefficient determined by the heterogeneous leakage model would have the higher accuracy. The new buckling search

  11. Characterization of silicon photomultipliers and validation of the electrical model

    Science.gov (United States)

    Peng, Peng; Qiang, Yi; Ross, Steve; Burr, Kent

    2018-04-01

    This paper introduces a systematic way to measure most features of the silicon photomultipliers (SiPM). We implement an efficient two-laser procedure to measure the recovery time. Avalanche probability was found to play an important role in explaining the right behavior of the SiPM recovery process. Also, we demonstrate how equivalent circuit parameters measured by optical tests can be used in SPICE modeling to predict details of the time constants relevant to the pulse shape. The SiPM properties measured include breakdown voltage, gain, diode capacitor, quench resistor, quench capacitor, dark count rate, photodetection efficiency, cross-talk and after-pulsing probability, and recovery time. We apply these techniques on the SiPMs from two companies: Hamamatsu and SensL.

  12. Silicon photomultiplier arrays for the LHCb scintillating fibre tracker

    CERN Multimedia

    Girard, Olivier Goran; Kuonen, Axel Kevin; Stramaglia, Maria Elena

    2017-01-01

    For the LHCb detector upgrade in 2019, a large scale scintillating fibre tracker read out with silicon photomultipliers is under construction. The harsh radiation environment (neutron and ionising radiation), the 40MHz read-out rate of the trigger less system and the large detector surface of 320m2 impose many challenges. We present the results from lab tests with 1MeV electrons and from the SPS test facility at CERN for the mulitchannel SiPM array that combines peak photo-detection efficiency of 48% and extremely low correlated noise. The measurements were performed with detectors irradiated with neutrons up to a fluence of 12*1011 neq/cm2 and single photon detection was maintained. First results of the characterization of the pre-series of 500 detectors delivered by Hamamatsu and irradiation studies on a large sample will be included.

  13. The silicon microstrip sensors of the ATLAS semiconductor tracker

    International Nuclear Information System (INIS)

    ATLAS SCT Collaboration; Spieler, Helmuth G.

    2007-01-01

    This paper describes the AC-coupled, single-sided, p-in-n silicon microstrip sensors used in the Semiconductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The sensor requirements, specifications and designs are discussed, together with the qualification and quality assurance procedures adopted for their production. The measured sensor performance is presented, both initially and after irradiation to the fluence anticipated after 10 years of LHC operation. The sensors are now successfully assembled within the detecting modules of the SCT, and the SCT tracker is completed and integrated within the ATLAS Inner Detector. Hamamatsu Photonics Ltd. supplied 92.2percent of the 15,392 installed sensors, with the remainder supplied by CiS

  14. The silicon microstrip sensors of the ATLAS semiconductor tracker

    Energy Technology Data Exchange (ETDEWEB)

    ATLAS SCT Collaboration; Spieler, Helmuth G.

    2007-04-13

    This paper describes the AC-coupled, single-sided, p-in-n silicon microstrip sensors used in the Semiconductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The sensor requirements, specifications and designs are discussed, together with the qualification and quality assurance procedures adopted for their production. The measured sensor performance is presented, both initially and after irradiation to the fluence anticipated after 10 years of LHC operation. The sensors are now successfully assembled within the detecting modules of the SCT, and the SCT tracker is completed and integrated within the ATLAS Inner Detector. Hamamatsu Photonics Ltd. supplied 92.2percent of the 15,392 installed sensors, with the remainder supplied by CiS.

  15. Pinning of fullerene lowest unoccupied molecular orbital edge at the interface with standing up copper phthalocyanine

    International Nuclear Information System (INIS)

    Wang, Chenggong; Irfan, Irfan; Turinske, Alexander J.; Gao, Yongli

    2012-01-01

    The electronic structure evolution of interfaces of fullerene (C 60 ) with copper phthalocyanine (CuPc) on highly oriented pyrolitic graphite (HOPG) and on native silicon oxide has been investigated with ultra-violet photoemission spectroscopy and inverse photoemission spectroscopy. The lowest unoccupied molecular orbital edge of C 60 was found to be pinned at the interface with CuPc on SiO 2 . A substantial difference in the electron affinity of CuPc on the two substrates was observed as the orientation of CuPc is lying flat on HOPG and standing up on SiO 2 . The ionization potential and electron affinity of C 60 were not affected by the orientation of CuPc due to the spherical symmetry of C 60 molecules. We observed band bending in C 60 on the standing-up orientation of CuPc molecules, while the energy levels of C 60 on the flat lying orientation of CuPc molecules were observed to be flat. - Highlights: ► Orientation of copper phthalocyanine (CuPc) on ordered graphite and silicon oxide. ► Pinning of lowest unoccupied molecular orbital edge of C60 to the Fermi level on CuPc. ► No C60 pinning or band bending was observed on flat laying CuPc. ► Results are useful for organic photovoltaic and organic light emitting diode research.

  16. Vacuum ultra-violet and ultra-violet scintillation light detection by means of silicon photomultipliers at cryogenic temperature

    Energy Technology Data Exchange (ETDEWEB)

    Falcone, A., E-mail: andrea.falcone@pv.infn.it [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Bertoni, R. [INFN Sezione di Milano Bicocca, Piazza della Scienza, 3, 20126 Milano (Italy); Boffelli, F. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Bonesini, M. [INFN Sezione di Milano Bicocca, Piazza della Scienza, 3, 20126 Milano (Italy); Cervi, T. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); Menegolli, A. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Montanari, C.; Prata, M.C.; Rappoldi, A.; Raselli, G.L.; Rossella, M.; Simonetta, M. [INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Spanu, M. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); Torti, M. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Zani, A. [INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy)

    2015-07-01

    We tested the performance of two types of silicon photomultipliers, AdvanSiD ASD-NUV-SiPM3S-P and Hamamatsu 3×3 MM-50 UM VUV2, both at room (300 K) and at liquid nitrogen (77 K) temperature: breakdown voltage, quenching resistance, signal shape, gain and dark counts rate have been studied as function of temperature. The response of the devices to ultra-violet light is also studied. - Highlights: • We tested 2 SiPMs both at room and at cryogenic temperature. • Breakdown voltage, quenching resistance, gain and dark rate were measured. • Efficiency for VUV light detection was measured.

  17. Whole-Pin Furnace system: An experimental facility for studying irradiated fuel pin behavior under potential reactor accident conditions

    International Nuclear Information System (INIS)

    Liu, Y.Y.; Tsai, H.C.; Donahue, D.A.; Pushis, D.O.; Savoie, F.E.; Holland, J.W.; Wright, A.E.; August, C.; Bailey, J.L.; Patterson, D.R.

    1990-05-01

    The whole-pin furnace system is a new in-cell experimental facility constructed to investigate how irradiated fuel pins may fail under potential reactor accident conditions. Extensive checkouts have demonstrated excellent performance in remote operation, temperature control, pin breach detection, and fission gas handling. The system is currently being used in testing of EBIR-II-irradiated Integral Fast Reactor (IFR) metal fuel pins; future testing will include EBR-II-irradiated mixed-oxide fuel pins. 7 refs., 4 figs

  18. Phase-sensitive optical processing in silicon waveguides

    DEFF Research Database (Denmark)

    Petermann, Klaus; Gajda, A.; Dziallas, Claudia

    2015-01-01

    Parametric optical signal processing is reviewed for silicon nano-rib-waveguides with a reverse-biased pin-junction. Phase-sensitive parametric amplification with a phase-sensitive extinction of more than 20 dB has been utilized for the regeneration of DPSK signals...

  19. Statistics of dislocation pinning at localized obstacles

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, A. [S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700098 (India); Bhattacharya, M., E-mail: mishreyee@vecc.gov.in; Barat, P. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064 (India)

    2014-10-14

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  20. Pinning impulsive control algorithms for complex network

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Wen [School of Information and Mathematics, Yangtze University, Jingzhou 434023 (China); Lü, Jinhu [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China); Chen, Shihua [College of Mathematics and Statistics, Wuhan University, Wuhan 430072 (China); Yu, Xinghuo [School of Electrical and Computer Engineering, RMIT University, Melbourne VIC 3001 (Australia)

    2014-03-15

    In this paper, we further investigate the synchronization of complex dynamical network via pinning control in which a selection of nodes are controlled at discrete times. Different from most existing work, the pinning control algorithms utilize only the impulsive signals at discrete time instants, which may greatly improve the communication channel efficiency and reduce control cost. Two classes of algorithms are designed, one for strongly connected complex network and another for non-strongly connected complex network. It is suggested that in the strongly connected network with suitable coupling strength, a single controller at any one of the network's nodes can always pin the network to its homogeneous solution. In the non-strongly connected case, the location and minimum number of nodes needed to pin the network are determined by the Frobenius normal form of the coupling matrix. In addition, the coupling matrix is not necessarily symmetric or irreducible. Illustrative examples are then given to validate the proposed pinning impulsive control algorithms.

  1. Development of a fast pin-by-pin transport solver in ARCADIA registered

    International Nuclear Information System (INIS)

    Geemert, R. van

    2009-01-01

    For satisfaction of future global customer needs, dedicated efforts are being coordinated internationally and pursued continuously at AREVA NP. The currently ongoing CONVERGENCE project is committed to the development of the ARCADIA registered next generation core simulation software package. ARCADIA registered will be put to global use by all AREVA NP business regions, for the entire spectrum of core design processes, licensing computations and safety studies. As part of the currently ongoing trend towards more sophisticated neutronics methodologies, an SP 3 nodal transport concept (van Geemert 2008) has been developed for ARTEMIS (Hobson 2008) which is the steady-state and transient core simulation part of ARCADIA registered . For enabling a high computational performance, the SP 3 calculations are accelerated by applying multi-level coarse mesh rebalancing (van Geemert 2006). In the current implementation, SP 3 is typically about 1.4 times as expensive computationally as SP 1 (diffusion). The developed SP 3 solution concept is foreseen as the future computational workhorse for many-group 3D pin-by-pin full core computations by ARCADIA registered . With the entire numerical workload being highly parallelizable through domain decomposition techniques, associated CPU-time requirements that adhere to the efficiency needs in the nuclear industry can be expected to become feasible in the near future. The accuracy enhancement obtainable by using SP 3 instead of SP 1 has been verified by a detailed comparison of ARTEMIS 16-group pin-by-pin SP N results with KAERI's DeCart reference results (Kozlowski 2003) for the 2D pin-by-pin Purdue UO 2 /MOX benchmark. Within the associated pin-by-pin grid, large pin-to-pin variations in cross-section values occur due to the explicit modelling of guide tubes, gadolinium pins as well as the heterogeneous distribution of MOX assemblies and UO 2 assemblies featuring significantly different burnups. With a pin-by-pin grid as

  2. PINS Testing and Modification for Explosive Identification

    International Nuclear Information System (INIS)

    Seabury, E.H.; Caffrey, A.J.

    2011-01-01

    The INL's Portable Isotopic Neutron Spectroscopy System (PINS)1 non-intrusively identifies the chemical fill of munitions and sealed containers. PINS is used routinely by the U.S. Army, the Defense Threat Reduction Agency, and foreign military units to determine the contents of munitions and other containers suspected to contain explosives, smoke-generating chemicals, and chemical warfare agents such as mustard and nerve gas. The objects assayed with PINS range from softball-sized M139 chemical bomblets to 200 gallon DOT 500X ton containers. INL had previously examined2 the feasibility of using a similar system for the identification of explosives, and based on this proof-of-principle test, the development of a dedicated system for the identification of explosives in an improvised nuclear device appears entirely feasible. INL has been tasked by NNSA NA-42 Render Safe Research and Development with the development of such a system.

  3. Measurements on irradiated L1 sensor prototypes for the D0 Run IIb silicon detector project

    Energy Technology Data Exchange (ETDEWEB)

    Ahsan, M.; Bolton, T.; Carnes, K.; /Kansas State U.; Demarteau, M.; /Fermilab; Demina, R.; /Rochester U.; Gray, T.; /Kansas State U.; Korjenevski, S.; /Rochester U.; Lehner, F.; /Zurich U.; Lipton, R.; Mao, H.S.; /Fermilab; McCarthy, R.; /SUNY, Stony Brook /Kansas State U. /Fermilab

    2010-01-01

    We report on irradiation studies of Hamamatsu prototype silicon microstrip detectors for layer 1 of the D0 upgrade project for Run IIb. The irradiation was carried out with 10 MeV protons up to proton fluence of 10{sup 14} p/cm{sup 2} at the J.R. Macdonald Laboratory, Manhatten, KS. The flux calibration was carefully checked using different dose normalization techniques. The results based on the obtained sensor leakage currents after irradiation show that the NIEL scaling hypothesis for low energy protons has to be applied with great care. We observe 30-40% less radiation damage in silicon for 10 MeV proton exposure than is expected from the predicted NIEL scaling.

  4. Measurements on irradiated L1 sensor prototypes for the D0 Run IIb silicon detector project

    International Nuclear Information System (INIS)

    Ahsan, M.; Bolton, T.; Carnes, K.; Demarteau, M.; Demina, R.; Gray, T.; Korjenevski, S.; Lehner, F.; Lipton, R.; Mao, H.S.; McCarthy, R.

    2010-01-01

    We report on irradiation studies of Hamamatsu prototype silicon microstrip detectors for layer 1 of the D0 upgrade project for Run IIb. The irradiation was carried out with 10 MeV protons up to proton fluence of 10 14 p/cm 2 at the J.R. Macdonald Laboratory, Manhatten, KS. The flux calibration was carefully checked using different dose normalization techniques. The results based on the obtained sensor leakage currents after irradiation show that the NIEL scaling hypothesis for low energy protons has to be applied with great care. We observe 30-40% less radiation damage in silicon for 10 MeV proton exposure than is expected from the predicted NIEL scaling.

  5. Peripheral pin alignment system for fuel assemblies

    International Nuclear Information System (INIS)

    Anthony, A.J.

    1981-01-01

    An alignment system is provided for nuclear fuel assemblies in a nuclear core. The core support structure of the nuclear reactor includes upwardly pointing alignment pins arranged in a square grid and engage peripheral depressions formed in the lateral periphery of the lower ends of each of the fuel assemblies of the core. In a preferred embodiment, the depressions are located at the corners of the fuel assemblies so that each depression includes one-quarter of a cylindrical void. Accordingly, each fuel assembly is positioned and aligned by one-quarter of four separate alignment pins which engage the fuel assemblies at their lower exterior corners. (author)

  6. Pinning, flux diodes and ratchets for vortices interacting with conformal pinning arrays

    International Nuclear Information System (INIS)

    Olson Reichhardt, C. J.; Wang, Y. L.; Argonne National Laboratory; Xiao, Z. L.; Northern Illinois University, DeKalb, IL

    2016-01-01

    A conformal pinning array can be created by conformally transforming a uniform triangular pinning lattice to produce a new structure in which the six-fold ordering of the original lattice is conserved but where there is a spatial gradient in the density of pinning sites. Here we examine several aspects of vortices interacting with conformal pinning arrays and how they can be used to create a flux flow diode effect for driving vortices in different directions across the arrays. Under the application of an ac drive, a pronounced vortex ratchet effect occurs where the vortices flow in the easy direction of the array asymmetry. When the ac drive is applied perpendicular to the asymmetry direction of the array, it is possible to realize a transverse vortex ratchet effect where there is a generation of a dc flow of vortices perpendicular to the ac drive due to the creation of a noise correlation ratchet by the plastic motion of the vortices. We also examine vortex transport in experiments and compare the pinning effectiveness of conformal arrays to uniform triangular pinning arrays. In conclusion, we find that a triangular array generally pins the vortices more effectively at the first matching field and below, while the conformal array is more effective at higher fields where interstitial vortex flow occurs.

  7. Design of a terahertz CW photomixer based on PIN and superlattice PIN devices

    DEFF Research Database (Denmark)

    Krozer, Viktor; Eichhorn, Finn

    2006-01-01

    We present the design of a photomixer LO based on standard and superlattice PIN diodes, operating at 1 THz. The design is based on a direct integration of a double slot antenna with the PIN device and a suitable matching circuit. The antenna has been designed together with a dielectric lens using...... Ansoft HFSS EM simulation. The large-signal PIN diode model employed in the work has been improved compared to our previously developed model presented earlier in a 3 THz design. We demonstrate that the antenna characteristic changes drastically with the device in place....

  8. Tapered leaf support pin for operating plant guide tubes

    International Nuclear Information System (INIS)

    Land, J.T.; Hopkins, R.J.; Ford, D.E.

    1991-01-01

    This patent describes a mounting system for removably mounting the lower flange of a control rod guide tube over an opening in the upper core plate of a nuclear reactor comprising at least one elongated support pin mounted on the guide tube lower flange and resiliently receivable in a bore formed in the upper core plate. It comprises a support pin having a longitudinal axis and comprising a first pin portion mountable on the guide tube lower flange, and a second pin portion receivable within the upper core plate bore, the second pin portion including a solid body section adjacent the first pin portion and having an outer diameter which is accommodated by the bore by a close clearance fit; locking means mounted on the first pin portion of the support pin for retaining the guide tube lower flange between the solid body section of the second pin portion and the locking means; and a washer disposed around the first pin portion between the locking means and the control rod guide tube flange, the washer and the locking means including mutually engaging rounded surfaces for eliminating bending moments and stresses on the support pin during mounting of the locking means on the first pin portion of the support pin

  9. Self-consistent modeling of amorphous silicon devices

    International Nuclear Information System (INIS)

    Hack, M.

    1987-01-01

    The authors developed a computer model to describe the steady-state behaviour of a range of amorphous silicon devices. It is based on the complete set of transport equations and takes into account the important role played by the continuous distribution of localized states in the mobility gap of amorphous silicon. Using one set of parameters they have been able to self-consistently simulate the current-voltage characteristics of p-i-n (or n-i-p) solar cells under illumination, the dark behaviour of field-effect transistors, p-i-n diodes and n-i-n diodes in both the ohmic and space charge limited regimes. This model also describes the steady-state photoconductivity of amorphous silicon, in particular, its dependence on temperature, doping and illumination intensity

  10. Study of a PIN photodiode as an ionizing radiation detector for aerospace use

    International Nuclear Information System (INIS)

    Nogueira, S.F.L.; Claro, L.H.; Santos, J.A.; Junior, J.R.; Federico, C.A.

    2017-01-01

    This work aims to study the use of the COTS PIN photodiode with an active area of 7.5 mm 2 as an ionizing radiation detector. The tests were performed with a 60 Co source and with low activity radioisotopic sources of 60 Co, 152 Eu, 137 Cs and 241 Am. The results were obtained by analyzing the current response generated by the photodiodes as a function of an attenuated dose rate in silicon in the range of 0.55 to 11.54 Gy / h

  11. Cladding properties under simulated fuel pin transients

    International Nuclear Information System (INIS)

    Hunter, C.W.; Johnson, G.D.

    1975-01-01

    A description is given of the HEDL fuel pin testing program utilizing a recently developed Fuel Cladding Transient Tester (FCTT) to generate the requisite mechanical property information on irradiated and unirradiated fast reactor fuel cladding under temperature ramp conditions. The test procedure is described, and data are presented

  12. Turban pin aspiration: new fashion, new syndrome.

    Science.gov (United States)

    Ilan, Ophir; Eliashar, Ron; Hirshoren, Nir; Hamdan, Kasem; Gross, Menachem

    2012-04-01

    Turban pin aspiration syndrome is a new clinical entity afflicting young Islamic girls wearing a turban.The goal of this study was to present our experience in diagnosis and treatment of this new entity, define its clinical and epidemiologic features, and shed a new light on the role of fashion in the increased incidence. A retrospective study in a tertiary university hospital. Review of clinical parameters and epidemiologic features of 26 patients diagnosed with turban pin aspiration syndrome admitted to the Hadassah-Hebrew University Hospitals in Jerusalem from 1990 to 2010. All patients were Muslim females with an average age of 16 years. In all cases, the history was positive for accidental aspiration. Most of the pins were located in the trachea (42%). In 20 cases, the pins were extracted by rigid bronchoscopy without major complications. Fluoroscopy-assisted rigid bronchoscopy was used successfully in three cases. In one case, the object was self-ejected by coughing before the bronchoscopy, and two patients were referred to the chest unit for thoracotomy. Clinicians should be aware of this distinct form of foreign body aspiration, its method of diagnosis, and extraction techniques. A cultural investigation showed a difference in the turban-fastening technique of young girls as compared with their mothers. Removal by rigid bronchoscopy is a safe method with a high success rate and should be considered as the preferred extraction method of choice. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

  13. Radiographic examination methods for fuel pins

    International Nuclear Information System (INIS)

    Smirnov, V.P.; Dvoretskii, V.G.

    1987-11-01

    To study the fast neutron reactor fuel pins structure the NIIAR Institute used x diffraction, neutronic radiography and autoradiographies. The two first methods are used for internal macrostructure studies, the third method for the plutonium and uranium radial distribution. These methods and the main results are indicated in this document [fr

  14. Physicist pins hopes on particle collider

    CERN Multimedia

    2007-01-01

    Physicist pins hopes on particle collider By Deseret Morning News Published: Monday, Dec. 31, 27 12:4 a.m. MST FONT Scott Thomas, a 187 State University graduate, is working at the frontiers of science. The theoretical physicist is crafting ways to extract fundamental secrets that seem certain to be uncovered by the Large Hadron Collider.

  15. Analytical method for reconstruction pin to pin of the nuclear power density distribution

    Energy Technology Data Exchange (ETDEWEB)

    Pessoa, Paulo O.; Silva, Fernando C.; Martinez, Aquilino S., E-mail: ppessoa@con.ufrj.br, E-mail: fernando@con.ufrj.br, E-mail: aquilino@imp.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    An accurate and efficient method for reconstructing pin to pin of the nuclear power density distribution, involving the analytical solution of the diffusion equation for two-dimensional neutron energy groups in homogeneous nodes, is presented. The boundary conditions used for analytic as solution are the four currents or fluxes on the surface of the node, which are obtained by Nodal Expansion Method (known as NEM) and four fluxes at the vertices of a node calculated using the finite difference method. The analytical solution found is the homogeneous distribution of neutron flux. Detailed distributions pin to pin inside a fuel assembly are estimated by the product of homogeneous flux distribution by local heterogeneous form function. Furthermore, the form functions of flux and power are used. The results obtained with this method have a good accuracy when compared with reference values. (author)

  16. Analytical method for reconstruction pin to pin of the nuclear power density distribution

    International Nuclear Information System (INIS)

    Pessoa, Paulo O.; Silva, Fernando C.; Martinez, Aquilino S.

    2013-01-01

    An accurate and efficient method for reconstructing pin to pin of the nuclear power density distribution, involving the analytical solution of the diffusion equation for two-dimensional neutron energy groups in homogeneous nodes, is presented. The boundary conditions used for analytic as solution are the four currents or fluxes on the surface of the node, which are obtained by Nodal Expansion Method (known as NEM) and four fluxes at the vertices of a node calculated using the finite difference method. The analytical solution found is the homogeneous distribution of neutron flux. Detailed distributions pin to pin inside a fuel assembly are estimated by the product of homogeneous flux distribution by local heterogeneous form function. Furthermore, the form functions of flux and power are used. The results obtained with this method have a good accuracy when compared with reference values. (author)

  17. Pinning control of complex networked systems synchronization, consensus and flocking of networked systems via pinning

    CERN Document Server

    Su, Housheng

    2013-01-01

    Synchronization, consensus and flocking are ubiquitous requirements in networked systems. Pinning Control of Complex Networked Systems investigates these requirements by using the pinning control strategy, which aims to control the whole dynamical network with huge numbers of nodes by imposing controllers for only a fraction of the nodes. As the direct control of every node in a dynamical network with huge numbers of nodes might be impossible or unnecessary, it’s then very important to use the pinning control strategy for the synchronization of complex dynamical networks. The research on pinning control strategy in consensus and flocking of multi-agent systems can not only help us to better understand the mechanisms of natural collective phenomena, but also benefit applications in mobile sensor/robot networks. This book offers a valuable resource for researchers and engineers working in the fields of control theory and control engineering.   Housheng Su is an Associate Professor at the Department of Contro...

  18. PROCOPE, Collision Probability in Pin Clusters and Infinite Rod Lattices

    International Nuclear Information System (INIS)

    Amyot, L.; Daolio, C.; Benoist, P.

    1984-01-01

    1 - Nature of physical problem solved: Calculation of directional collision probabilities in pin clusters and infinite rod lattices. 2 - Method of solution: a) Gauss integration of analytical expressions for collision probabilities. b) alternately, an approximate closed expression (not involving integrals) may be used for pin-to-pin interactions. 3 - Restrictions on the complexity of the problem: number of fuel pins must be smaller than 62; maximum number of groups of symmetry is 300

  19. Silicon photomultipliers in AMIGA muon counters

    Energy Technology Data Exchange (ETDEWEB)

    Botti, Ana Martina [Institut fuer Kernphysik, Karlsruher Institut fuer Technologie (Germany); Instituto de Tecnologias en Deteccion y Astroparticulas (ITeDA) (Argentina); Collaboration: Pierre-Auger-Collaboration

    2016-07-01

    The project AMIGA (Auger Muons and Infill for the Ground Array) aims to extend the energy range at the Pierre Auger Observatory to observe cosmic rays of lower energies (down to ∝10{sup 17} eV) and to study the transition from extragalactic to galactic cosmic rays. AMIGA is compounded by an infill of surface detectors (employing Cherenkov radiation detection in water) and muon counters. The AMIGA muon counters consist of an array of buried modules composed of 64 scintillator bars, a multi-pixel Photo Multiplier Tube (PMT) and the corresponding electronic of acquisition which works along with the surface detector. Currently, ITeDA is evaluating the feasibility of replacing PMTs with silicon photomultipliers (SiPM) without performing any substantial modification in the digital readout nor in the mechanical design. I present calibration results of a prototype module associated to the surface detector Toune of the Pierre Auger Observatory using a SiPM Hamamatsu S1257-100C plugged to the standard AMIGA front-end electronics. In addition, a study concerning gain stability and temperature variation has also been performed and is reported. I finally discuss a comparison between traces measured by both photodetectors (PMT and SiPM) for modules associated to the surface detector Toune.

  20. Radiation Damage Studies of Silicon Photomultipliers

    CERN Document Server

    Bohn, P; Hazen, E.; Heering, A.; Rohlf, J.; Freeman, J.; Los, Sergey V.; Cascio, E.; Kuleshov, S.; Musienko, Y.; Piemonte, C.

    2008-01-01

    We report on the measurement of the radiation hardness of silicon photomultipliers (SiPMs) manufactured by Fondazione Bruno Kessler in Italy (1 mm$^2$ and 6.2 mm$^2$), Center of Perspective Technology and Apparatus in Russia (1 mm$^2$ and 4.4 mm$^2$), and Hamamatsu Corporation in Japan (1 mm$^2$). The SiPMs were irradiated using a beam of 212 MeV protons at Massachusetts General Hospital, receiving fluences of up to $3 \\times 10^{10}$ protons per cm$^2$ with the SiPMs at operating voltage. Leakage currents were read continuously during the irradiation. The delivery of the protons was paused periodically to record scope traces in response to calibrated light pulses to monitor the gains, photon detection efficiencies, and dark counts of the SiPMs. The leakage current and dark noise are found to increase with fluence. Te leakage current is found to be proportional to the mean square deviation of the noise distribution, indicating the dark counts are due to increased random individual pixel activation, while SiPM...

  1. Optimization study on pin tip diameter of an impact-pin nozzle at high pressure ratio

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, C. Palani; Lee, Kwon Hee [FMTRC, Daejoo Machinery Co. Ltd., Daegu (Korea, Republic of); Park, Tae Choon; Cha, Bong Jun [Engine Components Research Team, Korea Aerospace Research Institute, Daejeon (Korea, Republic of); Kim, Heuy Dong [Dept. of Mechanical Engineering, Andong National University, Andong (Korea, Republic of)

    2016-09-15

    Wet compression system is typically installed in a gas turbine engine to increase the net power output and efficiency. A crucial component of the wet compression system is the nozzle which generates fine water droplets for injection into the compressor. The main objective of present work is to optimize a kind of nozzle called impact-pin spray nozzle and thereby produce better quality droplets. To achieve this, the dynamics occurring in the water jet impinging on the pin tip, the subsequent formation of water sheet, which finally breaks into water droplets, must be studied. In this manuscript, the progress on the numerical studies on impact-pin nozzle are reported. A small computational domain covering the orifice, pin tip and the region where primary atomization occurs is selected for numerical analysis. The governing equations are selected in three dimensional cartesian form and simulations are performed to predict the dynamics of water jet impinging on the pin. Systematic studies were carried out and the results leading to the choice of turbulence model and the effect of pin tip diameter are reported here. Further studies are proposed to show the future directions of the present research work.

  2. A physico-genetic module for the polarisation of auxin efflux carriers PIN-FORMED (PIN)

    Science.gov (United States)

    Hernández-Hernández, Valeria; Barrio, Rafael A.; Benítez, Mariana; Nakayama, Naomi; Romero-Arias, José Roberto; Villarreal, Carlos

    2018-05-01

    Intracellular polarisation of auxin efflux carriers is crucial for understanding how auxin gradients form in plants. The polarisation dynamics of auxin efflux carriers PIN-FORMED (PIN) depends on both biomechanical forces as well as chemical, molecular and genetic factors. Biomechanical forces have shown to affect the localisation of PIN transporters to the plasma membrane. We propose a physico-genetic module of PIN polarisation that integrates biomechanical, molecular, and cellular processes as well as their non-linear interactions. The module was implemented as a discrete Boolean model and then approximated to a continuous dynamic system, in order to explore the relative contribution of the factors mediating PIN polarisation at the scale of single cell. Our models recovered qualitative behaviours that have been experimentally observed and enable us to predict that, in the context of PIN polarisation, the effects of the mechanical forces can predominate over the activity of molecular factors such as the GTPase ROP6 and the ROP-INTERACTIVE CRIB MOTIF-CONTAINING PROTEIN RIC1.

  3. Primary hip spica with crossed retrograde intramedullary rush pins ...

    African Journals Online (AJOL)

    Bursitis and penetration of pins at the site of Rush pin insertion is a complication associated with this method of treatment. Conclusion: Closed reduction and internal fixation with crossed Rush pins was a superior treatment method in terms of early weight bearing and restoration of normal anatomy. Keywords: Femoral ...

  4. Some aspects of continuum physics used in fuel pin modeling

    International Nuclear Information System (INIS)

    Bard, F.E.

    1975-06-01

    The mathematical formulation used in fuel pin modeling is described. Fuel pin modeling is not a simple extension of the experimental and interpretative methods used in classical mechanics. New concepts are needed to describe materials in a reactor environment. Some aspects of continuum physics used to develop these new constitutive equations for fuel pins are presented. (U.S.)

  5. Post irradiation examination on test fuel pins for PWR

    International Nuclear Information System (INIS)

    Fogaca Filho, N.; Ambrozio Filho, F.

    1981-01-01

    Certain aspects of irradiation technology on test fuel pins for PWR, are studied. The results of post irradiation tests, performed on test fuel pins in hot cells, are presented. The results of the tests permit an evaluation of the effects of irradiation on the fuel and cladding of the pin. (Author) [pt

  6. Temperature and pinning strength dependence of the critical current of a superconductor with a square periodic array of pinning sites

    International Nuclear Information System (INIS)

    Benkraouda, M.; Obaidat, I.M.; Al Khawaja, U.

    2006-01-01

    We have conducted extensive series of molecular dynamic simulations on driven vortex lattices interacting with periodic square arrays of pinning sites. In solving the over damped equation of vortex motion we took into account the vortex-vortex repulsion interaction, the attractive vortex-pinning interaction, and the driving Lorentz force at several values of temperature. We have studied the effect of varying the driving Lorentz force and varying the pinning strength on the critical current for several pinning densities, and temperature values. We have found that the pinning strength play an important role in enhancing the critical current over the whole temperature range. At low temperatures, the critical current was found to increase linearly with increasing the pinning strengths for all pinning densities. As the temperature increases, the effect of small pinning strengths diminishes and becomes insignificant at high temperatures

  7. Room Temperature Direct Band Gap Emission from Ge p-i-n Heterojunction Photodiodes

    Directory of Open Access Journals (Sweden)

    E. Kasper

    2012-01-01

    Full Text Available Room temperature direct band gap emission is observed for Si-substrate-based Ge p-i-n heterojunction photodiode structures operated under forward bias. Comparisons of electroluminescence with photoluminescence spectra allow separating emission from intrinsic Ge (0.8 eV and highly doped Ge (0.73 eV. Electroluminescence stems from carrier injection into the intrinsic layer, whereas photoluminescence originates from the highly n-doped top layer because the exciting visible laser wavelength is strongly absorbed in Ge. High doping levels led to an apparent band gap narrowing from carrier-impurity interaction. The emission shifts to higher wavelengths with increasing current level which is explained by device heating. The heterostructure layer sequence and the light emitting device are similar to earlier presented photodetectors. This is an important aspect for monolithic integration of silicon microelectronics and silicon photonics.

  8. Pinning impulsive synchronization of stochastic delayed coupled networks

    International Nuclear Information System (INIS)

    Tang Yang; Fang Jian-An; Wong W K; Miao Qing-Ying

    2011-01-01

    In this paper, the pinning synchronization problem of stochastic delayed complex network (SDCN) is investigated by using a novel hybrid pinning controller. The proposed hybrid pinning controller is composed of adaptive controller and impulsive controller, where the two controllers are both added to a fraction of nodes in the network. Using the Lyapunov stability theory and the novel hybrid pinning controller, some sufficient conditions are derived for the exponential synchronization of such dynamical networks in mean square. Two numerical simulation examples are provided to verify the effectiveness of the proposed approach. The simulation results show that the proposed control scheme has a fast convergence rate compared with the conventional adaptive pinning method. (general)

  9. Compact silicon photonic resonance-sssisted variable optical attenuator.

    Science.gov (United States)

    Wang, Xiaoxi; Aguinaldo, Ryan; Lentine, Anthony; DeRose, Christopher; Starbuck, Andrew L; Trotter, Douglas; Pomerene, Andrew; Mookherjea, Shayan

    2016-11-28

    A two-part silicon photonic variable optical attenuator is demonstrated in a compact footprint which can provide a high extinction ratio at wavelengths between 1520 nm and 1620 nm. The device was made by following the conventional p-i-n waveguide section by a high-extinction-ratio second-order microring filter section. The rings provide additional on-off contrast by utilizing a thermal resonance shift, which harvested the heat dissipated by current injection in the p-i-n junction. We derive and discuss a simple thermal-resistance model in explanation of these effects.

  10. The pin pixel detector--neutron imaging

    CERN Document Server

    Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Rhodes, N J; Schooneveld, E M; Simmons, J E; Stephenson, R

    2002-01-01

    The development and testing of a neutron gas pixel detector intended for application in neutron diffraction studies is reported. Using standard electrical connector pins as point anodes, the detector is based on a commercial 100 pin connector block. A prototype detector of aperture 25.4 mmx25.4 mm has been fabricated, giving a pixel size of 2.54 mm which matches well to the spatial resolution typically required in a neutron diffractometer. A 2-Dimensional resistive divide readout system has been adapted to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics. The timing properties of the device match well to the requirements of the ISIS-pulsed neutron source.

  11. Elementary pinning force for a superconducting vortex

    International Nuclear Information System (INIS)

    Hyun, O.B.; Finnemore, D.K.; Schwartzkopf, L.; Clem, J.R.

    1987-01-01

    The elementary pinning force f/sub p/ has been measured for a single vortex trapped in one of the superconducting layers of a cross-strip Josephson junction. At temperatures close to the transition temperature the vortex can be pushed across the junction by a transport current. The vortex is found to move in a small number of discrete steps before it exits the junction. The pinning force for each site is found to be asymmetric and to have a value of about 10/sup -6/ N/m at the reduced temperature, t = T/T/sub c/ = 0.95. As a function of temperature, f/sub p/ is found to vary approximately as (1-t)/sup 3/2/. .AE

  12. Top-nozzle mounted replacement guide pin assemblies

    International Nuclear Information System (INIS)

    Gilmore, C.B.; Andrews, W.H.

    1993-01-01

    A replacement guide pin assembly is provided for aligning a nuclear fuel assembly with an upper core plate of a nuclear reactor core. The guide pin assembly includes a guide pin body having a radially expandable base insertable within a hole in the top nozzle, a ferrule insertable within the guide pin base and capable of imparting a radially and outwardly directed force on the expandable base to expand it within the hole of the top nozzle and thereby secure the guide pin body to the top nozzle in response to a predetermined displacement of the ferrule relative to the guide pin body along its longitudinal axis, and a lock screw interfitted with the ferrule and threaded into the guide pin body so as to produce the predetermined displacement of the ferrule. (author)

  13. Timing analysis of PWR fuel pin failures

    International Nuclear Information System (INIS)

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J.; Straka, M.

    1992-09-01

    Research has been conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B ampersand W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin bumup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PFL/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B ampersand W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B ampersand W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design bumup. Using peaking factors commensurate widi actual bumups would result in longer intervals for both reactor designs. This document also contains appendices A through J of this report

  14. Performance measurements of hybrid PIN diode arrays

    International Nuclear Information System (INIS)

    Jernigan, J.G.; Arens, J.F.; Collins, T.; Herring, J.; Shapiro, S.L.; Wilburn, C.D.

    1990-05-01

    We report on the successful effort to develop hybrid PIN diode arrays and to demonstrate their potential as components of vertex detectors. Hybrid pixel arrays have been fabricated by the Hughes Aircraft Co. by bump bonding readout chips developed by Hughes to an array of PIN diodes manufactured by Micron Semiconductor Inc. These hybrid pixel arrays were constructed in two configurations. One array format having 10 x 64 pixels, each 120 μm square, and the other format having 256 x 256 pixels, each 30 μm square. In both cases, the thickness of the PIN diode layer is 300 μm. Measurements of detector performance show that excellent position resolution can be achieved by interpolation. By determining the centroid of the charge cloud which spreads charge into a number of neighboring pixels, a spatial resolution of a few microns has been attained. The noise has been measured to be about 300 electrons (rms) at room temperature, as expected from KTC and dark current considerations, yielding a signal-to-noise ratio of about 100 for minimum ionizing particles. 4 refs., 13 figs

  15. Silicon Qubits

    Energy Technology Data Exchange (ETDEWEB)

    Ladd, Thaddeus D. [HRL Laboratories, LLC, Malibu, CA (United States); Carroll, Malcolm S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2018-02-28

    Silicon is a promising material candidate for qubits due to the combination of worldwide infrastructure in silicon microelectronics fabrication and the capability to drastically reduce decohering noise channels via chemical purification and isotopic enhancement. However, a variety of challenges in fabrication, control, and measurement leaves unclear the best strategy for fully realizing this material’s future potential. In this article, we survey three basic qubit types: those based on substitutional donors, on metal-oxide-semiconductor (MOS) structures, and on Si/SiGe heterostructures. We also discuss the multiple schema used to define and control Si qubits, which may exploit the manipulation and detection of a single electron charge, the state of a single electron spin, or the collective states of multiple spins. Far from being comprehensive, this article provides a brief orientation to the rapidly evolving field of silicon qubit technology and is intended as an approachable entry point for a researcher new to this field.

  16. Three-Terminal Amorphous Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Cheng-Hung Tai

    2011-01-01

    Full Text Available Many defects exist within amorphous silicon since it is not crystalline. This provides recombination centers, thus reducing the efficiency of a typical a-Si solar cell. A new structure is presented in this paper: a three-terminal a-Si solar cell. The new back-to-back p-i-n/n-i-p structure increased the average electric field in a solar cell. A typical a-Si p-i-n solar cell was also simulated for comparison using the same thickness and material parameters. The 0.28 μm-thick three-terminal a-Si solar cell achieved an efficiency of 11.4%, while the efficiency of a typical a-Si p-i-n solar cell was 9.0%. Furthermore, an efficiency of 11.7% was achieved by thickness optimization of the three-terminal solar cell.

  17. Applicability of the diffusion and simplified P3 theories for BWR pin-by-pin core analysis

    International Nuclear Information System (INIS)

    Tada, Kenichi; Yamamoto, Akio; Kitamura, Yasunori; Yamane, Yoshihiro; Watanabe, Masato; Noda, Hiroshi

    2007-01-01

    The pin-by-pin fine mesh core calculation method is considered as a candidate of next-generation core calculation method for BWR. In this study, the diffusion and the simplified P 3 (SP 3 ) theories are applied to the pin-by-pin core analysis of BWR. Performances of the diffusion and the SP 3 theories for cell-homogeneous pin-by-pin fine mesh BWR core analysis are evaluated through comparison with cell-heterogeneous detailed transport calculation by the method of characteristics (MOC). In this study, two-dimensional, 2x2 multi-assemblies geometry is used to compare the prediction accuracies of the diffusion and the SP 3 theories. The 2x2 multi- assemblies geometry consists of two types of 9x9 UO 2 assembly that have two different enrichment splittings. To mitigate the cell-homogenization error, the SPH method is applied for the pin-by-pin fine mesh calculation. The SPH method is a technique that reproduces a result of heterogeneous calculation by that of homogeneous calculation. The calculation results indicated that diffusion theory shows larger discrepancy than that of SP 3 theory on pin-wise fission rates. Furthermore, the accuracy of the diffusion theory would not be sufficient for the pin-by-pin fine mesh calculation. In contrast to the diffusion theory, the SP 3 theory shows much better accuracy on pin wise fission rates. Therefore, if the SP 3 theory is applied, the accuracy of the pin-by-pin fine mesh BWR core analysis will be higher and will be sufficient for production calculation. (author)

  18. Abrasive Wear Resistance of Tool Steels Evaluated by the Pin-on-Disc Testing

    Science.gov (United States)

    Bressan, José Divo; Schopf, Roberto Alexandre

    2011-05-01

    Present work examines tool steels abrasion wear resistance and the abrasion mechanisms which are one main contributor to failure of tooling in metal forming industry. Tooling used in cutting and metal forming processes without lubrication fails due to this type of wear. In the workshop and engineering practice, it is common to relate wear resistance as function of material hardness only. However, there are others parameters which influences wear such as: fracture toughness, type of crystalline structure and the occurrence of hard precipitate in the metallic matrix and also its nature. In the present investigation, the wear mechanisms acting in tool steels were analyzed and, by normalized tests, wear resistance performance of nine different types of tool steels were evaluated by pin-on-disc testing. Conventional tool steels commonly used in tooling such as AISI H13 and AISI A2 were compared in relation to tool steels fabricated by sintering process such as Crucible CPM 3V, CPM 9V and M4 steels. Friction and wear testing were carried out in a pin-on-disc automated equipment which pin was tool steel and the counter-face was a abrasive disc of silicon carbide. Normal load of 5 N, sliding velocity of 0.45 m/s, total sliding distance of 3000 m and room temperature were employed. The wear rate was calculated by the Archard's equation and from the plotted graphs of pin cumulated volume loss versus sliding distance. Specimens were appropriately heat treated by quenching and three tempering cycles. Percentage of alloying elements, metallographic analyses of microstructure and Vickers microhardness of specimens were performed, analyzed and correlated with wear rate. The work is concluded by the presentation of a rank of tool steel wear rate, comparing the different tool steel abrasion wear resistance: the best tool steel wear resistance evaluated was the Crucible CPM 9V steel.

  19. Characterization of three high efficiency and blue sensitive silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Otte, Adam Nepomuk, E-mail: otte@gatech.edu; Garcia, Distefano; Nguyen, Thanh; Purushotham, Dhruv

    2017-02-21

    We report about the optical and electrical characterization of three high efficiency and blue sensitive Silicon photomultipliers from FBK, Hamamatsu, and SensL. Key features of the tested devices when operated at 90% breakdown probability are peak photon detection efficiencies between 40% and 55%, temperature dependencies of gain and PDE that are less than 1%/°C, dark rates of ∼50 kHz/mm{sup 2} at room temperature, afterpulsing of about 2%, and direct optical crosstalk between 6% and 20%. The characteristics of all three devices impressively demonstrate how the Silicon-photomultiplier technology has improved over the past ten years. It is further demonstrated how the voltage and temperature characteristics of a number of quantities can be parameterized on the basis of physical models. The models provide a deeper understanding of the device characteristics over a wide bias and temperature range. They also serve as examples how producers could provide the characteristics of their SiPMs to users. A standardized parameterization of SiPMs would enable users to find the optimal SiPM for their application and the operating point of SiPMs without having to perform measurements thus significantly reducing design and development cycles.

  20. A proposed parameterization of interface discontinuity factors depending on neighborhood for pin-by-pin diffusion computations for LWR

    International Nuclear Information System (INIS)

    Herrero, Jose Javier; Garcia-Herranz, Nuria; Ahnert, Carol

    2011-01-01

    There exists an interest in performing full core pin-by-pin computations for present nuclear reactors. In such type of problems the use of a transport approximation like the diffusion equation requires the introduction of correction parameters. Interface discontinuity factors can improve the diffusion solution to nearly reproduce a transport solution. Nevertheless, calculating accurate pin-by-pin IDF requires the knowledge of the heterogeneous neutron flux distribution, which depends on the boundary conditions of the pin-cell as well as the local variables along the nuclear reactor operation. As a consequence, it is impractical to compute them for each possible configuration. An alternative to generate accurate pin-by-pin interface discontinuity factors is to calculate reference values using zero-net-current boundary conditions and to synthesize afterwards their dependencies on the main neighborhood variables. In such way the factors can be accurately computed during fine-mesh diffusion calculations by correcting the reference values as a function of the actual environment of the pin-cell in the core. In this paper we propose a parameterization of the pin-by-pin interface discontinuity factors allowing the implementation of a cross sections library able to treat the neighborhood effect. First results are presented for typical PWR configurations. (author)

  1. A proposed parameterization of interface discontinuity factors depending on neighborhood for pin-by-pin diffusion computations for LWR

    Energy Technology Data Exchange (ETDEWEB)

    Herrero, Jose Javier; Garcia-Herranz, Nuria; Ahnert, Carol, E-mail: herrero@din.upm.es, E-mail: nuria@din.upm.es, E-mail: carol@din.upm.es [Departamento de Ingenieria Nuclear, Universidad Politecnica de Madrid (Spain)

    2011-07-01

    There exists an interest in performing full core pin-by-pin computations for present nuclear reactors. In such type of problems the use of a transport approximation like the diffusion equation requires the introduction of correction parameters. Interface discontinuity factors can improve the diffusion solution to nearly reproduce a transport solution. Nevertheless, calculating accurate pin-by-pin IDF requires the knowledge of the heterogeneous neutron flux distribution, which depends on the boundary conditions of the pin-cell as well as the local variables along the nuclear reactor operation. As a consequence, it is impractical to compute them for each possible configuration. An alternative to generate accurate pin-by-pin interface discontinuity factors is to calculate reference values using zero-net-current boundary conditions and to synthesize afterwards their dependencies on the main neighborhood variables. In such way the factors can be accurately computed during fine-mesh diffusion calculations by correcting the reference values as a function of the actual environment of the pin-cell in the core. In this paper we propose a parameterization of the pin-by-pin interface discontinuity factors allowing the implementation of a cross sections library able to treat the neighborhood effect. First results are presented for typical PWR configurations. (author)

  2. Genome-wide identification and evolution of the PIN-FORMED (PIN) gene family in Glycine max.

    Science.gov (United States)

    Liu, Yuan; Wei, Haichao

    2017-07-01

    Soybean (Glycine max) is one of the most important crop plants. Wild and cultivated soybean varieties have significant differences worth further investigation, such as plant morphology, seed size, and seed coat development; these characters may be related to auxin biology. The PIN gene family encodes essential transport proteins in cell-to-cell auxin transport, but little research on soybean PIN genes (GmPIN genes) has been done, especially with respect to the evolution and differences between wild and cultivated soybean. In this study, we retrieved 23 GmPIN genes from the latest updated G. max genome database; six GmPIN protein sequences were changed compared with the previous database. Based on the Plant Genome Duplication Database, 18 GmPIN genes have been involved in segment duplication. Three pairs of GmPIN genes arose after the second soybean genome duplication, and six occurred after the first genome duplication. The duplicated GmPIN genes retained similar expression patterns. All the duplicated GmPIN genes experienced purifying selection (K a /K s genome sequence of 17 wild and 14 cultivated soybean varieties. Our research provides useful and comprehensive basic information for understanding GmPIN genes.

  3. Robustness of pinning a general complex dynamical network

    International Nuclear Information System (INIS)

    Wang Lei; Sun Youxian

    2010-01-01

    This Letter studies the robustness problem of pinning a general complex dynamical network toward an assigned synchronous evolution. Several synchronization criteria are presented to guarantee the convergence of the pinning process locally and globally by construction of Lyapunov functions. In particular, if a pinning strategy has been designed for synchronization of a given complex dynamical network, then no matter what uncertainties occur among the pinned nodes, synchronization can still be guaranteed through the pinning. The analytical results show that pinning control has a certain robustness against perturbations on network architecture: adding, deleting and changing the weights of edges. Numerical simulations illustrated by scale-free complex networks verify the theoretical results above-acquired.

  4. Is magnetic pinning a dominant mechanism in Nb-Ti

    International Nuclear Information System (INIS)

    Cooley, L.D.; Lee, P.J.; Larbalestier, D.C.

    1991-01-01

    In this paper, the authors compare the pinning behavior of an artificial pinning center (APC) composite and a nanometer-filament Nb 46.5 wt% Ti composite to that of a conventional Nb 48 wt% Ti composite. The microstructure of the APC composite resembles the conventional composite, where ribbons of normal metal form the pinning centers, whereas the nanometer-filament composite has no internal normal metal but pins instead at the filament surface. The APC composite exhibits much stronger pinning relative to B c 2 than the conventional composite (21.4 GN/m 3 , 7 T vs. 18.9 GN/m 3 , 11 T), which is possibly due to the increased amount of pinning center (50 vol.% vs. 25 vol.%), however the proximity effect reduces the B c 2 unfavorably

  5. Ferromagnetic artificial pinning centers in multifilamentary superconducting wires

    International Nuclear Information System (INIS)

    Wang, J.Q.; Rizzo, N.D.; Prober, D.E.

    1997-01-01

    The authors fabricated multifilamentary NbTi wires with ferromagnetic (FM) artificial pinning centers (APCs) to enhance the critical current density (J c ) in magnetic fields. They used a bundle and draw technique to process the APC wires with either Ni or Fe as the pinning centers. Both wires produced higher J c in the high field range (5-9 T) than previous non-magnetic APC wires similarly processed, even though the authors have not yet optimized pin percentage. Using a magnetometer they found that the pins remained ferromagnetic for the wires with maximum J c . However, they did observe a substantial loss of FM material for the wires where the pin diameter approached 3 nm. Thus, they expect further enhancement of J c with better pin quality

  6. Correlation of creep and swelling with fuel pin performance

    International Nuclear Information System (INIS)

    Jackson, R.J.; Washburn, D.F.; Garner, F.A.; Gilbert, E.R.

    1975-09-01

    The HEDL PNL-11 experiment described was one in a series of fueled subassemblies irradiated in EBR-II to demonstrate the adequacy of the FFTF fuel pin design. The cladding material, dimensions, and fuel density are prototypic of FFTF. Because neutron flux in EBR-II is lower than in FFTF, the uranium enrichment is higher in these experimental fuel pins, irradiated in EBR-II, than the FFTF enrichment for comparable linear heat rates. Some pertinent oprating conditions for the center fuel pin in this experiment are listed. This 37-pin subassembly represents, at 110,000 MWd/MTM, the highest burnup yet attained by a prototypic FFTF subassembly. Similarly, this is the highest fluence presently attained by prototypic fuel pins. A cladding breach occurred in one fuel pin which is presently being examined. Results are presented and discussed

  7. Analysis of three idealized reactor configurations: plate, pin, and homogeneous

    International Nuclear Information System (INIS)

    McKnight, R.D.

    1983-01-01

    Detailed Monte Carlo calculations have been performed for three distinct configurations of an idealized fast critical assembly. This idealized assembly was based on the LMFBR benchmark critical assembly ZPR-6/7. In the first configuration, the entire core was loaded with the plate unit cell of ZPR-6/7. In the second configuration, the entire core was loaded with the ZPR sodium-filled pin calandria. The actual ZPR pin calandria are loaded with mixed (U,Pu) oxide pins which closely match the composition of the ZPR-6/7 plate unit cell. For the present study, slight adjustments were made in the atom concentrations and the length of the pin calandria in order to make the core boundaries and average composition for the pin-cell configuration identical to those of the plate-cell configuration. In the third configuration, the core was homogeneous, again with identical core boundaries and average composition as the plate and pin configurations

  8. Analytic models for fuel pin transient performance

    International Nuclear Information System (INIS)

    Bard, F.E.; Fox, G.L.; Washburn, D.F.; Hanson, J.E.

    1976-09-01

    HEDL's ability to analyze various mechanisms that operate within a fuel pin has progressed substantially through development of codes such as PECTCLAD, which solves cladding response, and DSTRESS, which solves fuel response. The PECTCLAD results show good correlation with a variety of mechanical tests on cladding material and also demonstrate the significance of cladding strength when applying the life fraction rule. The DSTRESS results have shown that fuel deforms sufficiently during overpower transient tests that available volumes are filled, whether in the form of a central cavity or start-up cracks

  9. Optimum Prestress of Tanks with Pinned Base

    DEFF Research Database (Denmark)

    Brøndum-Nielsen, Troels

    1998-01-01

    Amin Ghali and Eleanor Elliott presented in their paper an interesting suggestion for prestressing of circular tanks without sliding joints. For many prestressed tanks the following construction procedure is adopted:In order to ensure compressive hoop forces in the wall near the base, the wall...... is allowed to slide freely in the radial direction during tensioning (free base).After tensioning such displacements are prevented (pinned base). The present paper addresses the problem of prestress of such tanks.Keywords: circular prestressing; creep properties; prestressed concrete; redistribution...

  10. On the obstructions to non-Cliffordian pin structures

    Energy Technology Data Exchange (ETDEWEB)

    Chamblin, A. (Dept. of Applied Maths and Theoretical Physics, Univ. of Cambridge (United Kingdom))

    1994-07-01

    We derive the topological obstructions to the existence of non-Cliffordian pin structures on four-dimensional spacetimes. We apply these obstructions to the study of non-Cliffordian pin-Lorentz cobordism. We note that our method of derivation applies equally well in any dimension and in any signature, and we present a general format for calculating obstructions in these situations. Finally, we interpret the breakdown of pin structure and discuss the relevance of this to aspects of physics. (orig.)

  11. Sodium erosion of boron carbide from breached absorber pins

    International Nuclear Information System (INIS)

    Basmajian, J.A.; Baker, D.E.

    1981-03-01

    The purpose of the irradiation experiment was to provide an engineering demonstration of the irradiation behavior of breached boron carbide absorber pins. By building defects into the cladding of prototypic absorber pins, and performing the irradiation under typical FFTF operating conditions, a qualitative assessment of the consequences of a breach was achieved. Additionally, a direct comparison of pin behavior with that of the ex-reactor test could be made

  12. Cell homogenization methods for pin-by-pin core calculations tested in slab geometry

    International Nuclear Information System (INIS)

    Yamamoto, Akio; Kitamura, Yasunori; Yamane, Yoshihiro

    2004-01-01

    In this paper, performances of spatial homogenization methods for fuel or non-fuel cells are compared in slab geometry in order to facilitate pin-by-pin core calculations. Since the spatial homogenization methods were mainly developed for fuel assemblies, systematic study of their performance for the cell-level homogenization has not been carried out. Importance of cell-level homogenization is recently increasing since the pin-by-pin mesh core calculation in actual three-dimensional geometry, which is less approximate approach than current advanced nodal method, is getting feasible. Four homogenization methods were investigated in this paper; the flux-volume weighting, the generalized equivalence theory, the superhomogenization (SPH) method and the nonlinear iteration method. The last one, the nonlinear iteration method, was tested as the homogenization method for the first time. The calculations were carried out in simplified colorset assembly configurations of PWR, which are simulated by slab geometries, and homogenization performances were evaluated through comparison with the reference cell-heterogeneous calculations. The calculation results revealed that the generalized equivalence theory showed best performance. Though the nonlinear iteration method can significantly reduce homogenization error, its performance was not as good as that of the generalized equivalence theory. Through comparison of the results obtained by the generalized equivalence theory and the superhomogenization method, important byproduct was obtained; deficiency of the current superhomogenization method, which could be improved by incorporating the 'cell-level discontinuity factor between assemblies', was clarified

  13. Development of 3D pseudo pin-by-pin calculation methodology in ANC

    International Nuclear Information System (INIS)

    Zhang, B.; Mayhue, L.; Huria, H.; Ivanov, B.

    2012-01-01

    Advanced cores and fuel assembly designs have been developed to improve operational flexibility, economic performance and further enhance safety features of nuclear power plants. The simulation of these new designs, along with strong heterogeneous fuel loading, have brought new challenges to the reactor physics methodologies currently employed in the industrial codes for core analyses. Control rod insertion during normal operation is one operational feature in the AP1000 R plant of Westinghouse next generation Pressurized Water Reactor (PWR) design. This design improves its operational flexibility and efficiency but significantly challenges the conventional reactor physics methods, especially in pin power calculations. The mixture loading of fuel assemblies with significant neutron spectrums causes a strong interaction between different fuel assembly types that is not fully captured with the current core design codes. To overcome the weaknesses of the conventional methods, Westinghouse has developed a state-of-the-art 3D Pin-by-Pin Calculation Methodology (P3C) and successfully implemented in the Westinghouse core design code ANC. The new methodology has been qualified and licensed for pin power prediction. The 3D P3C methodology along with its application and validation will be discussed in the paper. (authors)

  14. Trending on Pinterest: an examination of pins about skin tanning.

    Science.gov (United States)

    Banerjee, Smita C; Rodríguez, Vivian M; Greene, Kathryn; Hay, Jennifer L

    2018-04-10

    Rates of melanoma and nonmelanoma skin cancers are on the rise in the USA with data revealing disproportionate increase in female young adults. The popularity of intentional skin tanning among U.S. adolescents is attributed to several factors, including prioritization of physical appearance, media images of tanned celebrities, ease of availability of artificial tanning facilities, and more recently, the prevalence and celebration of tanned skin on social media. Pinterest, as the third most popular social media platform, was searched for "pins" about skin tanning. The resultant "pins" were examined to understand the extent and characteristics of skin tanning portrayed on Pinterest. We analyzed pins on Pinterest about skin tanning (n = 501) through a quantitative content analysis. Overall, results indicated an overwhelmingly protanning characteristic of pins about skin tanning on Pinterest, with over 85% of pins promoting tanning behavior. The pins were generally characterized by the portrayal of a female subject (61%) and provided positive reinforcement for tanning (49%). Use of tanning for enhancing appearance was the main positive outcome expectancy portrayed in the pins (35%), and nudity or exposure of skin on arms (32%) and legs (31%) was evident in about a third of pins. With overwhelmingly positive pins promoting tanning, use of female subjects, exhibiting nudity, and appearance enhancement, there seems be to a consistent targeting of female users to accept tanning as a socially acceptable and popular behavior. The findings indicate a need for developing sun protection messages and the leveraging of social media for dissemination of skin cancer prevention and detection messages.

  15. The pin pixel detector--X-ray imaging

    CERN Document Server

    Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Simmons, J E; Stephenson, R

    2002-01-01

    The development and testing of a soft X-ray gas pixel detector, which uses connector pins for the anodes is reported. Based on a commercial 100 pin connector block, a prototype detector of aperture 25.4 mm centre dot 25.4 mm can be economically fabricated. The individual pin anodes all show the expected characteristics of small gas detectors capable of counting rates reaching 1 MHz per pin. A 2-dimensional resistive divide readout system has been developed to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics.

  16. Reconstruction calculation of pin power for ship reactor core

    International Nuclear Information System (INIS)

    Li Haofeng; Shang Xueli; Chen Wenzhen; Wang Qiao

    2010-01-01

    Aiming at the limitation of the software that pin power distribution for ship reactor core was unavailable, the calculation model and method of the axial and radial pin power distribution were proposed. Reconstruction calculations of pin power along axis and radius was carried out by bicubic and bilinear interpolation and cubic spline interpolation, respectively. The results were compared with those obtained by professional reactor physical soft with fine mesh difference. It is shown that our reconstruction calculation of pin power is simple and reliable as well as accurate, which provides an important theoretic base for the safety analysis and operating administration of the ship nuclear reactor. (authors)

  17. Vortex pinning landscape in MOD-TFA YBCO nanostroctured films

    Science.gov (United States)

    Gutierrez, J.; Puig, T.; Pomar, A.; Obradors, X.

    2008-03-01

    A methodology of general validity to study vortex pinning in YBCO based on Jc transport measurements is described. It permits to identify, separate and quantify three basic vortex pinning contributions associated to anisotropic-strong, isotropic-strong and isotropic-weak pinning centers. Thereof, the corresponding vortex pinning phase diagrams are built up. This methodology is applied to the new solution-derived YBCO nanostructured films, including controlled interfacial pinning by the growth of nanostructured templates by means of self-assembled processes [1] and YBCO-BaZrO3 nanocomposites prepared by modified solution precursors. The application of the methodology and comparison with a standard solution-derived YBCO film [2], enables us to identify the nature and the effect of the additional pinning centers induced. The nanostructured templates films show c-axis pinning strongly increased, controlling most of the pinning phase diagram. On the other hand, the nanocomposites have achieved so far, the highest pinning properties in HTc-superconductors [3], being the isotropic-strong defects contribution the origin of their unique properties. [1] M. Gibert et al, Adv. Mat. vol 19, p. 3937 (2007) [2] Puig.T et al, SuST EUCAS 2007 (to be published) [3] J. Gutierrez et al, Nat. Mat. vol. 6, p. 367 (2007) * Work supported by HIPERCHEM, NANOARTIS and MAT2005-02047

  18. ITP Hanford Type 40 pin electrical connector failure analysis

    International Nuclear Information System (INIS)

    Imrich, K.J.

    1993-01-01

    Corrosion products observed on the ITP Hanford Type 40 pin electrical connectors would be expected to adversely affect the power and control signals supplied to process equipment in the filter cell by the connectors. Corrosion products were consistent with those found on similar pins in DWPF. The recommendations based on the findings in this investigation are as follows: (1) Replace male and female rhodium plated pins with gold plated pins. (2) Replace the galvanized carbon steel spring on the male connector with a stainless steel spring. (3) Install protective caps over Hanford connectors when jumpers are removed

  19. Fuel-pin cladding transient failure strain criterion

    International Nuclear Information System (INIS)

    Bard, F.E.; Duncan, D.R.; Hunter, C.W.

    1983-01-01

    A criterion for cladding failure based on accumulated strain was developed for mixed uranium-plutonium oxide fuel pins and used to interpret the calculated strain results from failed transient fuel pin experiments conducted in the Transient Reactor Test (TREAT) facility. The new STRAIN criterion replaced a stress-based criterion that depends on the DORN parameter and that incorrectly predicted fuel pin failure for transient tested fuel pins. This paper describes the STRAIN criterion and compares its prediction with those of the stress-based criterion

  20. Dynamic Phases of Vortices in Superconductors with Periodic Pinning

    International Nuclear Information System (INIS)

    Reichhardt, C.; Olson, C.; Nori, F.

    1997-01-01

    We present results from extensive simulations of driven vortex lattices interacting with periodic arrays of pinning sites. Changing an applied driving force produces a rich variety of novel dynamical plastic flow phases which are very distinct from those observed in systems with random pinning arrays. Signatures of the transition between these different dynamical phases include sudden jumps in the current-voltage curves as well as marked changes in the vortex trajectories and vortex lattice order. Several dynamical phase diagrams are obtained as a function of commensurability, pinning strength, and spatial order of the pinning sites. copyright 1997 The American Physical Society

  1. Positioning and locking device for fuel pin to grid attachment

    International Nuclear Information System (INIS)

    Frick, T.M.; Wineman, A.L.

    1976-01-01

    A positioning and locking device for fuel pin to grid attachment provides an inexpensive means of positively positioning and locking the individual fuel pins which make up the driver fuel assemblies used in nuclear reactors. The device can be adapted for use with a currently used attachment grid assembly design and insures that the pins remain in their proper position throughout the in-reactor life of the assembly. This device also simplifies fuel bundle assembly in that a complete row of fuel pins can be added to the bundle during each step of assembly. 8 claims, 8 drawing figures

  2. Heat transfer in a fuel pin shipping container

    International Nuclear Information System (INIS)

    Ingham, J.G.

    1980-01-01

    Maximum cladding temperatures occur when the IDENT 1578 fuel pin shipping container is installed in the T-3 Cask. The maximum allowable cladding temperature of 800 0 F is reached when the rate of energy deposited in the 19-pin basket reaches 400 watts. Since 45% of the energy which is generated in the fuel escapes the 19-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 400/.55 = 727 watts. Similarly, the maximum allowable cladding temperature of 800 0 F is reached when the rate of energy deposited in the 40-pin basket reaches 465 watts. Since 33% of the energy which is generated in the fuel escapes the 40-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 465/.66 = 704 watts. The IDENT 1578 fuel pin shipping container therefore meets its thermal design criteria. IDENT 1578 can handle fuel pins with a decay heat load of 600 watts while maintaining the maximum fuel pin cladding temperature below 800 0 F. The emissivities which were determined from the test results for the basket tubes and container are relatively low and correspond to new, shiny conditions. As the IDENT 1578 container is exposed to high temperatures for extended periods of time during the transportation of fuel pins, the emissivities will probably increase. This will result in reduced temperatures

  3. Nano-engineered pinning centres in YBCO superconducting films

    Energy Technology Data Exchange (ETDEWEB)

    Crisan, A., E-mail: adrian.crisan@infim.ro [National Institute for Materials Physics Bucharest, 105 bis Atomistilor Str., 077125 Magurele (Romania); School of Metallurgy and Materials, University of Birmingham, Edgbaston, B15 2TT Birmingham (United Kingdom); Dang, V.S. [School of Metallurgy and Materials, University of Birmingham, Edgbaston, B15 2TT Birmingham (United Kingdom); Nano and Energy Center, VNU Hanoi University of Science, 334 Nguyen Trai, Thanh Xuan, Hanoi (Viet Nam); Mikheenko, P. [School of Metallurgy and Materials, University of Birmingham, Edgbaston, B15 2TT Birmingham (United Kingdom); Department of Physics, University of Oslo, P.O. Box 1048 Blindern, N-0316 Oslo (Norway)

    2017-02-15

    Highlights: • Power applications of YBCO films/coated conductors in technological relevant magnetic fields requires nano-engineered pinning centre. • Three approaches have been proposed: substrate decoration, quasi-multilayers, and targets with secondary phase nano-inclusions. • Combination of all three approaches greatly increased critical current in YBCO films. • Bulk pinning force, pinning potential, and critical current density are estimated and discussed in relation with the type and strength of pinning centres related to the defects evidenced by Transmission Electron Microscopy. - Abstract: For practical applications of superconducting materials in applied magnetic fields, artificial pinning centres in addition to natural ones are required to oppose the Lorentz force. These pinning centres are actually various types of defects in the superconductor matrix. The pinning centres can be categorised on their dimension (volume, surface or point) and on their character (normal cores or Δκ cores). Different samples have been produced by Pulsed Laser Deposition, with various thicknesses, temperatures and nanostructured additions to the superconducting matrix. They have been characterized by SQUID Magnetic Properties Measurement System and Physical Properties Measurement System, as well as by Transmission Electron Microscopy (TEM). Correlations between pinning architecture, TEM images, and critical currents at various fields and field orientations will be shown for a large number of YBa{sub 2}Cu{sub 3}O{sub x} films with various types and architectures of artificial pinning centres.

  4. FABRICE process for the refrabrication of experimental pins in a hot cell, from pins pre-irradiated in power reactors

    International Nuclear Information System (INIS)

    Vignesoult, N.; Atabek, R.; Ducas, S.

    1982-06-01

    The Fabrice ''hot cell refabrication'' process for small pins from very long irradiated fuel elements was developed at the CEA to allow parametric studies of the irradiation behavior of pins from nuclear power plants. Since this operation required complete assurance of the validity of the process, qualification of the fabrication was performed on test pins, refabricated in the hot cell, as well as irradiation qualification. The latter qualification was intended to demonstrate that, in identical experimental irradiation conditions, the refabricated Fabrice pins behaved in the same way as whole pins with the same initial characteristics. This qualification of the Fabrice process, dealing with more than twenty pins at different burnups, showed that fabrication did not alter: the inherent characteristics of the sampled fuel element and the irradiation behavior of the sampled fuel element [fr

  5. Material accountancy for metallic fuel pin casting

    International Nuclear Information System (INIS)

    Bucher, R.G.; Orechwa, Y.; Beitel, J.C.

    1995-01-01

    The operation of the Fuel Conditioning Facility (FCF) is based on the electrometallurgical processing of spent metallic reactor fuel. The pin casting operation, although only one of several operations in FCF, was the first to be on-line. As such, it has served to demonstrate the material accountancy system in many of its facets. This paper details, for the operation of the pin casting process with depleted uranium, the interaction between the mass tracking system (MTG) and some of the ancillary computer codes which generate pertinent information for operations and material accountancy. It is necessary to distinguish between two types of material balance calculations -- closeout for operations and material accountancy for safeguards. The two have much in common, for example, the mass tracking system database and the calculation of an inventory difference, but, in general, are not congruent with regard to balance period and balance spatial domain. Moreover, the objective, assessment, and reporting requirements of the calculated inventory difference are very different in the two cases

  6. The Egyptian Hair Pin: practical, sacred, fatal

    Directory of Open Access Journals (Sweden)

    Joann Fletcher

    2016-11-01

    Full Text Available Generally regarded as little more than a mundane tool employed in daily life, the humble hairpin occasionally played a rather more prominent role in history than has perhaps been appreciated. As the most ancient implements associated with hair styling, simple pins of bone and ivory were commonly employed in Egypt by c.4000 BC as a means of securing long hair in an upswept style (e.g. Petrie and Mace 1901, 21, 34. Although their occasional use by men undermines the assumption that hairpins are 'a relatively certain example of a “gendered” artefact' (Wilfong 1997, 67, the vast majority have been found in female burials. They can be made of bone and ivory, wood, steatite, glass, gold, silver and bronze, and two 12cm long bronze examples were found within the hair of Princess Ahmosi c.1550 BC (Fletcher 1995, 376, 441 while the hair of an anonymous woman at Gurob c.AD 110 had been secured in a bun with pins of bone, tortoiseshell and silver (Walker and Bierbrier 1997, 209.

  7. Method and device for cleaning fuel pins

    International Nuclear Information System (INIS)

    Matsumoto, Kaname; Oohigashi, Yoshiaki.

    1985-01-01

    Purpose: To remove clads or scales deposited on the outer surface of fuel pins in BWR type reactors. Method: A fuel assembly taken out of a reactor core is vertically contained without detaching a channel box in a scrubber tower disposed in a liquid tight manner within a fuel pool. Then, a specifically prepared slurry is caused to flow and uprise from the bottom of the scrubber tower into the channel box and then discharged from the top of the tower. The slurry is prepared by mixing pure water and granules (for example, as activated carbon, ion exchanger resin, iron and molecular sieve) of such a granular size as not causing clogging in the channel box of the fuel assembly and having a larger specific gravity than pure water. The slurry flown into the channel box scrubs the surface of fuel pins to scrape off clads or scales. Then, discharged slurry is sent to a hydraulic cyclone to separate the granules from the clads or scales. (Ikeda, J.)

  8. Lightning Pin Injection Testing on MOSFETS

    Science.gov (United States)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.; Koppen, Sandra V.; Mielnik, John J.; Vaughan, Roger K.; Wysocki, Philip F.; Celaya, Jose R.; Saha, Sankalita

    2009-01-01

    Lightning transients were pin-injected into metal-oxide-semiconductor field-effect transistors (MOSFETs) to induce fault modes. This report documents the test process and results, and provides a basis for subsequent lightning tests. MOSFETs may be present in DC-DC power supplies and electromechanical actuator circuits that may be used on board aircraft. Results show that unprotected MOSFET Gates are susceptible to failure, even when installed in systems in well-shielded and partial-shielded locations. MOSFET Drains and Sources are significantly less susceptible. Device impedance decreased (current increased) after every failure. Such a failure mode may lead to cascading failures, as the damaged MOSFET may allow excessive current to flow through other circuitry. Preliminary assessments on a MOSFET subjected to 20-stroke pin-injection testing demonstrate that Breakdown Voltage, Leakage Current and Threshold Voltage characteristics show damage, while the device continues to meet manufacturer performance specifications. The purpose of this research is to develop validated tools, technologies, and techniques for automated detection, diagnosis and prognosis that enable mitigation of adverse events during flight, such as from lightning transients; and to understand the interplay between lightning-induced surges and aging (i.e. humidity, vibration thermal stress, etc.) on component degradation.

  9. Development of Silicon Photomultipliers and their Applications to GlueX Calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Elton S. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-07-01

    The GlueX experiment is a photoproduction experiment in Hall D at Jefferson Lab that is being commissioned for use with the new 12 GeV accelerator. The purpose of the experiment is to search for Hybrid mesons, which are mesons with quark and gluon degrees of freedom. The barrel calorimeter of GlueX is instrumented with 4000 large-area (1.2 x1.2 cm2) silicon photomultipliers (SiPMs). These photon sensors have properties similar to vacuum photomultipliers, but are unaffected by high magnetic fields. In our experiment they operate in magnetic fields exceeding 1T. After extensive tests with a variety of sensors, we chose the S12045(X) custom SiPM arrays manufactured by Hamamatsu Corporation, also known as multi-pixel photon counters (MPPCs). We will give an overview of this new technology as well as the experience gained during two commissioning periods with beam.

  10. The Silicon Microstrip Sensors of the ATLAS SemiConductor Tracker

    CERN Document Server

    Ahmad, A; Allport, P P; Alonso, J; Andricek, L; Apsimon, R J; Barr, A J; Bates, R L; Beck, G A; Bell, P J; Belymam, A; Benes, J; Berg, C M; Bernabeu, J; Bethke, S; Bingefors, N; Bizzell, J P; Bohm, J; Brenner, R; Brodbeck, T J; Bruckman De Renstrom, P; Buttar, C M; Campbell, D; Carpentieri, C; Carter, A A; Carter, J R; Charlton, D G; Casse, G-L; Chilingarov, A; Cindro, V; Ciocio, A; Civera, J V; Clark, A G; Colijn, A-P; Costa, M J; Dabrowski, W; Danielsen, K M; Dawson, I; Demirkoz, B; Dervan, P; Dolezal, Z; Dorholt, O; Duerdoth, I P; Dwuznik, M; Eckert, S; Ekelöf, T; Eklund, L; Escobar, C; Fasching, D; Feld, L; Ferguson, D P S; Ferrere, D; Fortin, R; Foster, J M; Fox, H; French, R; Fromant, B P; Fujita, K; Fuster, J; Gadomski, S; Gallop, B J; Garcia, C; Garcia-Navarro, J E; Gibson, M D; Gonzalez, S; Gonzalez-Sevilla, S; Goodrick, M J; Gornicki, E; Green, C; Greenall, A; Grigson, C; Grillo, A A; Grosse-Knetter, J; Haber, C; Handa, T; Hara, K; Harper, R S; Hartjes, F G; Hashizaki, T; Hauff, D; Hessey, N P; Hill, J C; Hollins, T I; Holt, S; Horazdovsky, T; Hornung, M; Hovland, K M; Hughes, G; Huse, T; Ikegami, Y; Iwata, Y; Jackson, J N; Jakobs, K; Jared, R C; Johansen, L G; Jones, R W L; Jones, T J; de Jong, P; Joseph, J; Jovanovic, P; Kaplon, J; Kato, Y; Ketterer, C; Kindervaag, I M; Kodys, P; Koffeman, E; Kohriki, T; Kohout, Z; Kondo, T; Koperny, S; van der Kraaij, E; Kral, V; Kramberger, G; Kudlaty, J; Lacasta, C; Limper, M; Linhart, V; Llosa, G; Lozano, M; Ludwig, I; Ludwig, J; Lutz, G; Macpherson, A; McMahon, S J; Macina, D; Magrath, C A; Malecki, P; Mandic, I; Marti-Garcia, S; Matsuo, T; Meinhardt, J; Mellado, B; Mercer, I J; Mikestikova, M; Mikuz, M; Minano, M; Mistry, J; Mitsou, V; Modesto, P; Mohn, B; Molloy, S D; Moorhead, G; Moraes, A; Morgan, D; Morone, M C; Morris, J; Moser, H-G; Moszczynski, A; Muijs, A J M; Nagai, K; Nakamura, Y; Nakano, I; Nicholson, R; Niinikoski, T; Nisius, R; Ohsugi, T; O'Shea, V; Oye, O K; Parzefall, U; Pater, J R; Pernegger, H; Phillips, P W; Posisil, S; Ratoff, P N; Reznicek, P; Richardson, J D; Richter, R H; Robinson, D; Roe, S; Ruggiero, G; Runge, K; Sadrozinski, H F W; Sandaker, H; Schieck, J; Seiden, A; Shinma, S; Siegrist, J; Sloan, T; Smith, N A; Snow, S W; Solar, M; Solberg, A; Sopko, B; Sospedra, L; Spieler, H; Stanecka, E; Stapnes, S; Stastny, J; Stelzer, F; Stradling, A; Stugu, B; Takashima, R; Tanaka, R; Taylor, G; Terada, S; Thompson, R J; Titov, M; Tomeda, Y; Tovey, D R; Turala, M; Turner, P R; Tyndel, M; Ullan, M; Unno, Y; Vickey, T; Vos, M; Wallny, R; Weilhammer, P; Wells, P S; Wilson, J A; Wolter, M; Wormald, M; Wu, S L; Yamashita, T; Zontar, D; Zsenei, A

    2007-01-01

    This paper describes the AC-coupled, single-sided, p-in-n silicon microstrip sensors used in the SemiConductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The sensor requirements, specifications and designs are discussed, together with the qualification and quality assurance procedures adopted for their production. The measured sensor performance is presented, both initially and after irradiation to the fluence anticipated after 10 years of LHC operation. The sensors are now successfully assembled within the detecting modules of the SCT, and the SCT tracker is completed and integrated within the ATLAS Inner Detector. Hamamatsu Photonics Ltd supplied 92.2% of the 15,392 installed sensors, with the remainder supplied by CiS.

  11. Development of silicon photomultipliers and their applications to GlueX calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Elton S., E-mail: elton@jlab.org [Jefferson Lab, Newport News, VA 23606 (United States)

    2016-07-07

    The GlueX experiment is a photoproduction experiment in Hall D at Jefferson Lab that is being commissioned for use with the new 12 GeV accelerator. The purpose of the experiment is to search for Hybrid mesons, which are mesons with quark and gluon degrees of freedom. The barrel calorimeter of GlueX is instrumented with 4000 large-area (1.2 × 1.2 cm{sup 2}) silicon photomultipliers (SiPMs). These photon sensors have properties similar to vacuum photomultipliers, but are unaffected by high magnetic fields. In our experiment they operate in magnetic fields exceeding 1T. After extensive tests with a variety of sensors, we chose the S12045(X) custom SiPM arrays manufactured by Hamamatsu Corporation, also known as multi-pixel photon counters (MPPCs). We will give an overview of this new technology as well as the experience gained during two commissioning periods with beam.

  12. Evaluation Of Silicon Diodes As IN-SITU Cryogenic Field Emission Detectors For SRF Cavity Development

    International Nuclear Information System (INIS)

    Palczewski, Ari; Geng, Rongli

    2012-01-01

    We performed in-situ cryogenic testing of four silicon diodes as possible candidates for field emission (FE) monitors of superconducting radio frequency (SRF) cavities during qualification testing and in accelerator cryo-modules. We evaluated diodes from 2 companies - from Hamamatsu corporation model S1223-01; and from OSI Optoelectronics models OSD35-LR-A, XUV-50C, and FIL-UV20. The measurements were done by placing the diodes in superfluid liquid helium near the top of a field emitting 9-cell cavity during its vertical test. For each diode, we will discuss their viability as a 2K cryogenic detector for FE mapping of SRF cavities and the directionality of S1223-01 in such environments. We will also present calibration curves between the diodes and JLab's standard radiation detector placed above the Dewar's top plate.

  13. New method for evaluating effective recovery time and single photoelectron response in silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Grodzicka, Martyna, E-mail: m.grodzicka@ncbj.gov.pl; Szczęśniak, Tomasz; Moszyński, Marek; Szawłowski, Marek; Grodzicki, Krystian

    2015-05-21

    The linearity of a silicon photomultiplier (SiPM) response depends on the number of APD cells and its effective recovery time and it is related to the intensity and duration of the detected light pulses. The aim of this study was to determine the effective recovery time on the basis of the measured SiPM response to light pulses of different durations. A closer analysis of the SiPM response to the light pulses shorter than the effective recovery time of APD cells led to a method for the evaluation of the single photoelectron response of the devices where the single photoelectron peak cannot be clearly measured. This is necessary in the evaluation of the number of fired APD cells (or the number of photoelectrons) in measurements with light pulses of various durations. Measurements were done with SiPMs manufactured by two companies: Hamamatsu and SensL.

  14. Radiation effects on breakdown in silicon multiguarded diodes

    International Nuclear Information System (INIS)

    Bisello, D.; Da Rold, M.; Franzin, L.; Wheadon, R.

    1996-01-01

    The authors have investigated the current-voltage characteristics of silicon PIN diodes with a number of different multiguard structures. These structures were designed to increase the overall device breakdown voltage. The same measurements were carried out after gamma irradiation at different doses and neutron irradiation at fluences beyond type-inversion. This study is a first step towards defining guard structures optimized for operation in high-radiation environments such as those expected at the LHC

  15. Minimum ionizing particle detection using amorphous silicon diodes

    Energy Technology Data Exchange (ETDEWEB)

    Xi, J.; Hollingsworth, R.E.; Buitrago, R.H. (Glasstech Solar, Inc., Wheat Ridge, CO (USA)); Oakley, D.; Cumalat, J.P.; Nauenberg, U. (Colorado Univ., Boulder (USA). Dept. of Physics); McNeil, J.A. (Colorado School of Mines, Golden (USA). Dept. of Physics); Anderson, D.F. (Fermi National Accelerator Lab., Batavia, IL (USA)); Perez-Mendez, V. (Lawrence Berkeley Lab., CA (USA))

    1991-03-01

    Hydrogenated amorphous silicon pin diodes have been used to detect minimum ionizing electrons with a pulse height signal-to-noise ratio exceeding 3. A distinct signal was seen for shaping times from 100 to 3000 ns. The devices used had a 54 {mu}m thick intrinsic layer and an active area of 0.1 cm{sup 2}. The maximum signal was 3200 electrons with a noise width of 950 electrons for a shaping time of 250 ns. (orig.).

  16. BARS - a heterogeneous code for 3D pin-by-pin LWR steady-state and transient calculation

    International Nuclear Information System (INIS)

    Avvakumov, A.V.; Malofeev, V.M.

    2000-01-01

    A 3D pin-by-pin dynamic model for LWR detailed calculation was developed. The model is based on a coupling of the BARS neutronic code with the RELAP5/MOD3.2 thermal hydraulic code. This model is intended to calculate a fuel cycle, a xenon transient, and a wide range of reactivity initiated accidents in a WWER and a PWR. Galanin-Feinberg heterogeneous method was realized in the BARS code. Some results for a validation of the heterogeneous method are presented for reactivity coefficients, a pin-by-pin power distribution, and a fast pulse transient. (Authors)

  17. Amorphous silicon pixel radiation detectors and associated thin film transistor electronics readout

    International Nuclear Information System (INIS)

    Perez-Mendez, V.; Cho, G.; Drewery, J.; Jing, T.; Kaplan, S.N.; Mireshghi, A.; Wildermuth, D.; Goodman, C.; Fujieda, I.

    1992-07-01

    We describe the characteristics of thin (1 μm) and thick (> 30 μm) hydrogenated amorphous silicon p-i-n diodes which are optimized for detecting and recording the spatial distribution of charged particles, x-ray, γ rays and thermal neutrons. For x-ray, γ ray, and charged particle detection we can use thin p-i-n photosensitive diode arrays coupled to evaporated layers of suitable scintillators. For thermal neutron detection we use thin (2∼5 μm) gadolinium converters on 30 μm thick a-Si:H diodes. For direct detection of minimum ionizing particles and others with high resistance to radiation damage, we use the thick p-i-n diode arrays. Diode and amorphous silicon readouts as well as polysilicon pixel amplifiers are described

  18. Study of a PIN photodiode as an ionizing radiation detector for aerospace use; Estudo de um fotodiodo PIN como detector de radiação ionizante para uso aeroespacial

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, S.F.L.; Claro, L.H.; Santos, J.A.; Junior, J.R.; Federico, C.A., E-mail: msetephanireis@hotmail.com [Instituto de Estudos Avançados (IEAv), São José dos Campos, SP (Brazil). Divisão de Física Aplicada

    2017-07-01

    This work aims to study the use of the COTS PIN photodiode with an active area of 7.5 mm{sup 2} as an ionizing radiation detector. The tests were performed with a {sup 60}Co source and with low activity radioisotopic sources of {sup 60}Co, {sup 152}Eu, {sup 137}Cs and {sup 241}Am. The results were obtained by analyzing the current response generated by the photodiodes as a function of an attenuated dose rate in silicon in the range of 0.55 to 11.54 Gy / h.

  19. Pinning in BSCCO above the ordinary irreversibility line

    Science.gov (United States)

    Indenbom, M. V.; van der Beek, C. J.; Berseth, V.; Konczykowski, M.; Motohira, N.; Berger, H.; Benoit, W.

    1996-12-01

    Frequency-dependent observations of magnetic flux structures are used to show that pinning plays a principal role in the whole mixed state in Bi2Sr2CaCu2O8 (BSCCO) single crystals. We speculate that the random pinning force on the moving vortices may dominate over thermal fluctuations and considerably modify the position of the vortex lattice phase transition.

  20. Inscuteable Regulates the Pins-Mud Spindle Orientation Pathway

    Science.gov (United States)

    Mauser, Jonathon F.; Prehoda, Kenneth E.

    2012-01-01

    During asymmetric cell division, alignment of the mitotic spindle with the cell polarity axis ensures that the cleavage furrow separates fate determinants into distinct daughter cells. The protein Inscuteable (Insc) is thought to link cell polarity and spindle positioning in diverse systems by binding the polarity protein Bazooka (Baz; aka Par-3) and the spindle orienting protein Partner of Inscuteable (Pins; mPins or LGN in mammals). Here we investigate the mechanism of spindle orientation by the Insc-Pins complex. Previously, we defined two Pins spindle orientation pathways: a complex with Mushroom body defect (Mud; NuMA in mammals) is required for full activity, whereas binding to Discs large (Dlg) is sufficient for partial activity. In the current study, we have examined the role of Inscuteable in mediating downstream Pins-mediated spindle orientation pathways. We find that the Insc-Pins complex requires Gαi for partial activity and that the complex specifically recruits Dlg but not Mud. In vitro competition experiments revealed that Insc and Mud compete for binding to the Pins TPR motifs, while Dlg can form a ternary complex with Insc-Pins. Our results suggest that Insc does not passively couple polarity and spindle orientation but preferentially inhibits the Mud pathway, while allowing the Dlg pathway to remain active. Insc-regulated complex assembly may ensure that the spindle is attached to the cortex (via Dlg) before activation of spindle pulling forces by Dynein/Dynactin (via Mud). PMID:22253744

  1. IMp: The customizable LEGO(®) Pinned Insect Manipulator.

    Science.gov (United States)

    Dupont, Steen; Price, Benjamin; Blagoderov, Vladimir

    2015-01-01

    We present a pinned insect manipulator (IMp) constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble.

  2. Geochemistry of silicon isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Tiping; Li, Yanhe; Gao, Jianfei; Hu, Bin [Chinese Academy of Geological Science, Beijing (China). Inst. of Mineral Resources; Jiang, Shaoyong [China Univ. of Geosciences, Wuhan (China).

    2018-04-01

    Silicon is one of the most abundant elements in the Earth and silicon isotope geochemistry is important in identifying the silicon source for various geological bodies and in studying the behavior of silicon in different geological processes. This book starts with an introduction on the development of silicon isotope geochemistry. Various analytical methods are described and compared with each other in detail. The mechanisms of silicon isotope fractionation are discussed, and silicon isotope distributions in various extraterrestrial and terrestrial reservoirs are updated. Besides, the applications of silicon isotopes in several important fields are presented.

  3. Cracking Bank PINs by Playing Mastermind

    Science.gov (United States)

    Focardi, Riccardo; Luccio, Flaminia L.

    The bank director was pretty upset noticing Joe, the system administrator, spending his spare time playing Mastermind, an old useless game of the 70ies. He had fought the instinct of telling him how to better spend his life, just limiting to look at him in disgust long enough to be certain to be noticed. No wonder when the next day the director fell on his chair astonished while reading, on the newspaper, about a huge digital fraud on the ATMs of his bank, with millions of Euros stolen by a team of hackers all around the world. The article mentioned how the hackers had 'played with the bank computers just like playing Mastermind', being able to disclose thousands of user PINs during the one-hour lunch break. That precise moment, a second before falling senseless, he understood the subtle smile on Joe's face the day before, while training at his preferred game, Mastermind.

  4. The lumped parameter model for fuel pins

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W S [Ontario Hydro, Toronto, ON (Canada)

    1996-12-31

    The use of a lumped fuel-pin model in a thermal-hydraulic code is advantageous because of computational simplicity and efficiency. The model uses an averaging approach over the fuel cross section and makes some simplifying assumptions to describe the transient equations for the averaged fuel, fuel centerline and sheath temperatures. It is shown that by introducing a factor in the effective fuel conductivity, the analytical solution of the mean fuel temperature can be modified to simulate the effects of the flux depression in the heat generation rate and the variation in fuel thermal conductivity. The simplified analytical method used in the transient equation is presented. The accuracy of the lumped parameter model has been compared with the results from the finite difference method. (author). 4 refs., 2 tabs., 4 figs.

  5. Alpha particles spectrometer with photodiode PIN

    International Nuclear Information System (INIS)

    Chacon R, A.; Hernandez V, R.; Hernandez D, V. M.; Vega C, H. R.; Ramirez G, J.

    2009-10-01

    The radiation propagates in form of electromagnetic waves or corpuscular radiation; if the radiation energy causes ionization in environment that crosses it is considered ionizing radiation. To detect radiation several detectors types are used, if the radiation are alpha particles are used detectors proportional type or trace elements. In this work the design results, construction and tests of an alpha particles spectrometer are presented, which was designed starting from a photodiode PIN type. The system design was simulated with a code for electronic circuits. With results of simulation phase was constructed the electronic phase that is coupled to a multichannel analyzer. The resulting electronic is evaluated analyzing the electronic circuit performance before an alphas triple source and alpha radiation that produce two smoke detectors of domestic use. On the tests phase we find that the system allows obtain, in a multichannel, the pulses height spectrum, with which we calibrate the system. (Author)

  6. Effective augmentation of networked systems and enhancing pinning controllability

    Science.gov (United States)

    Jalili, Mahdi

    2018-06-01

    Controlling dynamics of networked systems to a reference state, known as pinning control, has many applications in science and engineering. In this paper, we introduce a method for effective augmentation of networked systems, while also providing high levels of pinning controllability for the final augmented network. The problem is how to connect a sub-network to an already existing network such that the pinning controllability is maximised. We consider the eigenratio of the augmented Laplacian matrix as a pinning controllability metric, and use graph perturbation theory to approximate the influence of edge addition on the eigenratio. The proposed metric can be effectively used to find the inter-network links connecting the disjoint networks. Also, an efficient link rewiring approach is proposed to further optimise the pinning controllability of the augmented network. We provide numerical simulations on synthetic networks and show that the proposed method is more effective than heuristic ones.

  7. Artificial pinning center technology to enhance vortex pinning in YBCO coated conductors

    International Nuclear Information System (INIS)

    Matsumoto, Kaname; Mele, Paolo

    2010-01-01

    Crystalline defects on the nano-scale, which are called artificial pinning centers (APCs), were successfully introduced into high-temperature superconductors (HTS) by nanotechnology, in order to strongly pin the quantized vortices. The critical current densities, J c , of the HTS films were dramatically improved by APCs. It is possible to form APCs in high-quality epitaxial films, keeping the desired dimensionality, volume fraction, spatial distribution and so on. The in-field J c of HTS films at 77 K was improved by one order of magnitude compared with previous values using APCs. This technology can be applied to the coated conductor technology in progress, and a high J c has already been reported. A current outline of the research is described in this review.

  8. Retractable Pin Tools for the Friction Stir Welding Process

    Science.gov (United States)

    1998-01-01

    Two companies have successfully commercialized a specialized welding tool developed at the Marshall Space Flight Center (MSFC). Friction stir welding uses the high rotational speed of a tool and the resulting frictional heat created from contact to crush, 'stir' together, and forge a bond between two metal alloys. It has had a major drawback, reliance on a single-piece pin tool. The pin is slowly plunged into the joint between two materials to be welded and rotated as high speed. At the end of the weld, the single-piece pin tool is retracted and leaves a 'keyhole,' something which is unacceptable when welding cylindrical objects such as drums, pipes and storage tanks. Another drawback is the requirement for different-length pin tools when welding materials of varying thickness. An engineer at the MSFC helped design an automatic retractable pin tool that uses a computer-controlled motor to automatically retract the pin into the shoulder of the tool at the end of the weld, preventing keyholes. This design allows the pin angle and length to be adjusted for changes in material thickness and results in a smooth hole closure at the end of the weld. Benefits of friction stir welding, using the MSFC retractable pin tool technology, include the following: The ability to weld a wide range of alloys, including previously unweldable and composite materials; provision of twice the fatigue resistance of fusion welds and no keyholes; minimization of material distortion; no creation of hazards such as welding fumes, radiation, high voltage, liquid metals, or arcing; automatic retraction of the pin at the end of the weld; and maintaining full penetration of the pin.

  9. A pinning puzzle: two similar, non-superconducting chemical deposits in YBCO-one pins, the other does not

    Energy Technology Data Exchange (ETDEWEB)

    Sawh, Ravi-Persad; Weinstein, Roy; Gandini, Alberto; Skorpenske, Harley; Parks, Drew, E-mail: Weinstein@uh.ed [Beam Particle Dynamics Laboratories, University of Houston, Houston, TX 77204-5005 (United States); Department of Physics, University of Houston, Houston, TX 77204-5005 (United States); Texas Center for Superconductivity at UH, University of Houston, Houston, TX 77204-5002 (United States)

    2009-09-15

    The pinning effects of two kinds of U-rich deposits in YBCO (YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}) are compared. One is a five-element compound, (U{sub 0.6}Pt{sub 0.4})YBa{sub 2}O{sub 6}, which is a paramagnetic double perovskite which forms as profuse stable nanosize deposits, and pins very well. The other is a four-element compound, (U{sub 0.4}Y{sub 0.6})BaO{sub 3}, which is a ferromagnetic single perovskite which forms as profuse stable nanosize deposits and pins very weakly or not at all. The pinning comparison is done with nearly equal deposit sizes and number of deposits per unit volume for the two compounds. Evidence for the pinning capability, chemical makeup, x-ray diffraction signature, and magnetic properties of the two compounds is reported.

  10. Low power frontend ASIC (Anusuchak) for dosimeter using Si-PIN detector

    International Nuclear Information System (INIS)

    Darad, A.; Chandratre, V.B.

    2010-01-01

    A low power ASIC (Anusuchak) for silicon PIN detector signal processing channel designed for pocket dosimeter in 0.35 μm CMOS process. The ASIC contains two channels one for Beta particle and other for Gamma ray. The channel is a CSA integrated with a shaper, gain stage and comparator with total power consumption of 4.6 mW. The ASIC has gain of 12 mV/fC and can be raised to 29 mV/fC without degrading the noise, power or linearity specification of the channel. The channel has a peaking time of 1.2 μs with baseline recovery within 5.3 μs and noise figure of 420 e- at 0 pF. The noise slope is 17 e-/pF. The ASIC is designed for single supply of 3.3 V for which battery is available. (author)

  11. Simulations of Si-PIN photodiode based detectors for underground explosives enhanced by ammonium nitrate

    Science.gov (United States)

    Yücel, Mete; Bayrak, Ahmet; Yücel, Esra Barlas; Ozben, Cenap S.

    2018-02-01

    Massive Ammonium Nitrate (NH4-NO3) based explosives buried underground are commonly used in terror attacks. These explosives can be detected using neutron scattering method with some limitations. Simulations are very useful tools for designing a possible detection system for these kind of explosives. Geant4 simulations were used for generating neutrons at 14 MeV energy and tracking them through the scattering off the explosive embedded in soil. Si-PIN photodiodes were used as detector elements in the design for their low costs and simplicity for signal readout electronics. Various neutron-charge particle converters were applied on to the surface of the photodiodes to increase the detection efficiency. Si-PIN photodiodes coated with 6LiF provided the best result for a certain energy interval. Energy depositions in silicon detector from all secondary particles generated including photons were taken into account to generate a realistic background. Humidity of soil, one of the most important parameter for limiting the detection, was also studied.

  12. Optimal pin enrichment distributions in nuclear reactor fuel bundles

    International Nuclear Information System (INIS)

    Lim, E.Y.

    1976-01-01

    A methodology has been developed to determine the fuel pin enrichment distribution that yields the best approximation to a prescribed power distribution in nuclear reactor fuel bundles. The problem is formulated as an optimization problem in which the optimal pin enrichments minimize the sum of squared deviations between the actual and prescribed fuel pin powers. A constant average enrichment constraint is imposed to ensure that a suitable value of reactivity is present in the bundle. When constraints are added that limit the fuel pins to a few enrichment types, one must determine not only the optimal values of the enrichment types but also the optimal distribution of the enrichment types amongst the pins. A matrix of boolean variables is used to describe the assignment of enrichment types to the pins. This nonlinear mixed integer programming problem may be rigorously solved with either exhaustive enumeration or branch and bound methods using a modification of the algorithm from the continuous problem as a suboptimization. Unfortunately these methods are extremely cumbersome and computationally overwhelming. Solutions which require only a moderate computational effort are obtained by assuming that the fuel pin enrichments in this problem are ordered as in the solution to the continuous problem. Under this assumption search schemes using either exhaustive enumeration or branch and bound become computationally attractive. An adaptation of the Hooke--Jeeves pattern search technique is shown to be especially efficient

  13. Roles of pinning strength and density in vortex melting

    International Nuclear Information System (INIS)

    Obaidat, I M; Khawaja, U Al; Benkraouda, M

    2008-01-01

    We have investigated the role of pinning strength and density on the equilibrium vortex-lattice to vortex-liquid phase transition under several applied magnetic fields. This study was conducted using a series of molecular dynamic simulations on several samples with different strengths and densities of pinning sites which are arranged in periodic square arrays. We have found a single solid-liquid vortex transition when the vortex filling factor n>1. We have found that, for fixed pinning densities and strengths, the melting temperature, T m , decreases almost linearly with increasing magnetic field. Our results provide direct numerical evidence for the significant role of both the strength and density of pinning centers on the position of the melting line. We have found that the vortex-lattice to vortex-liquid melting line shifts up as the pinning strength or the pinning density was increased. The effect on the melting line was found to be more pronounced at small values of strength and density of pinning sites

  14. Loss of Pin1 Suppresses Hedgehog-Driven Medulloblastoma Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Tao Xu

    2017-03-01

    Full Text Available Medulloblastoma is the most common malignant brain tumor in children. Therapeutic approaches to medulloblastoma (combination of surgery, radiotherapy, and chemotherapy have led to significant improvements, but these are achieved at a high cost to quality of life. Alternative therapeutic approaches are needed. Genetic mutations leading to the activation of the Hedgehog pathway drive tumorigenesis in ~30% of medulloblastoma. In a yeast two-hybrid proteomic screen, we discovered a novel interaction between GLI1, a key transcription factor for the mediation of Hedgehog signals, and PIN1, a peptidylprolyl cis/trans isomerase that regulates the postphosphorylation fate of its targets. The GLI1/PIN1 interaction was validated by reciprocal pulldowns using epitope-tagged proteins in HEK293T cells as well as by co-immunoprecipiations of the endogenous proteins in a medulloblastoma cell line. Our results support a molecular model in which PIN1 promotes GLI1 protein abundance, thus contributing to the positive regulation of Hedgehog signals. Most importantly, in vivo functional analyses of Pin1 in the GFAP-tTA;TRE-SmoA1 mouse model of Hedgehog-driven medulloblastoma demonstrate that the loss of Pin1 impairs tumor development and dramatically increases survival. In summary, the discovery of the GLI1/PIN1 interaction uncovers PIN1 as a novel therapeutic target in Hedgehog-driven medulloblastoma tumorigenesis.

  15. Characterization of the passivation processes for PIN structures

    Energy Technology Data Exchange (ETDEWEB)

    Avila Garcia, Alejandro; Reyes Barranca, Mario Alfredo [Instituto Politecnico Nacional, Mexico, D.F (Mexico); Zarate Corona, Oscar [Universidad Autonoma de Puebla, Puebla (Mexico)

    2001-02-01

    Result on the evaluation of PIN structures made on crystalline silicon, processed in our laboratory, which underwent several gettering treatments are reported. Structures were evaluated through the measurement of lifetime {tau} and I-V characteristic. Also, deep levels due to defects were characterized; the activation energy (E{sub c} -E{sub t}), capture cross section {sigma} and relative concentration (N{sub t} / N{sub d}) were obtained. Techniques used in the characterization were Output Circuit Voltage Decay (OCVD), Current-Voltage measurements (I-V) and Deep Level Transient Spectroscopy (DLTS), respectively. These measurements show variations in the parameters, as a result of the gettering techniques applied. The best results were achieved for two types of samples: the first having high phosphorus concentration, no backside damage and annealed at 850 Celsius degrees without HCI atmosphere; the second having low phosphorus concentration, no backside damage and annealed at 850 Celsius degrees without HCI atmosphere. For these samples, the minority carrier lifetime was near 3{upsilon}s, the I-V characteristics imply that conductivity modulation takes place within the intrinsic region even for low voltages, as in commercial diodes. Two defects were observed to remain after the gettering processes: one is related to the phosphorus-vacant pair and the other to the divacancy. Concentrations could be decreased from {approx}4 x 10{sup 1}1cm{sup -3} down to 3 x 10{sup -9} cm{sup -3} for the first and down to 2 x 10{sup 1}0 cm{sup -3} for the second one. [Spanish] Se reportan resultados de la evaluacion de estructuras PIN en silicio procesadas en nuestro laboratorio, las cuales fueron sometidas a diversos tratamientos de gettering. Las estructuras fueron evaluadas a traves de la medicion de tiempo de vida {tau} y la caracteristica I-V. Se caracterizaron tambien los defectos que introducen niveles profundos en la region activa del dispositivo, obteniendo energia de

  16. Enhancing the far-UV sensitivity of silicon CMOS imaging arrays

    Science.gov (United States)

    Retherford, K. D.; Bai, Yibin; Ryu, Kevin K.; Gregory, J. A.; Welander, Paul B.; Davis, Michael W.; Greathouse, Thomas K.; Winter, Gregory S.; Suntharalingam, Vyshnavi; Beletic, James W.

    2014-07-01

    We report our progress toward optimizing backside-illuminated silicon PIN CMOS devices developed by Teledyne Imaging Sensors (TIS) for far-UV planetary science applications. This project was motivated by initial measurements at Southwest Research Institute (SwRI) of the far-UV responsivity of backside-illuminated silicon PIN photodiode test structures described in Bai et al., SPIE, 2008, which revealed a promising QE in the 100-200 nm range as reported in Davis et al., SPIE, 2012. Our effort to advance the capabilities of thinned silicon wafers capitalizes on recent innovations in molecular beam epitaxy (MBE) doping processes. Key achievements to date include: 1) Representative silicon test wafers were fabricated by TIS, and set up for MBE processing at MIT Lincoln Laboratory (LL); 2) Preliminary far-UV detector QE simulation runs were completed to aid MBE layer design; 3) Detector fabrication was completed through the pre-MBE step; and 4) Initial testing of the MBE doping process was performed on monitoring wafers, with detailed quality assessments. Early results suggest that potential challenges in optimizing the UV-sensitivity of silicon PIN type CMOS devices, compared with similar UV enhancement methods established for CCDs, have been mitigated through our newly developed methods. We will discuss the potential advantages of our approach and briefly describe future development steps.

  17. Substrate and Passivation Techniques for Flexible Amorphous Silicon-Based X-ray Detectors.

    Science.gov (United States)

    Marrs, Michael A; Raupp, Gregory B

    2016-07-26

    Flexible active matrix display technology has been adapted to create new flexible photo-sensing electronic devices, including flexible X-ray detectors. Monolithic integration of amorphous silicon (a-Si) PIN photodiodes on a flexible substrate poses significant challenges associated with the intrinsic film stress of amorphous silicon. This paper examines how altering device structuring and diode passivation layers can greatly improve the electrical performance and the mechanical reliability of the device, thereby eliminating one of the major weaknesses of a-Si PIN diodes in comparison to alternative photodetector technology, such as organic bulk heterojunction photodiodes and amorphous selenium. A dark current of 0.5 pA/mm² and photodiode quantum efficiency of 74% are possible with a pixelated diode structure with a silicon nitride/SU-8 bilayer passivation structure on a 20 µm-thick polyimide substrate.

  18. Fuel pin design algorithm for conceptual design studies

    International Nuclear Information System (INIS)

    Uselman, J.P.

    1979-01-01

    Two models are available which are currently verified by part of the requirements and which are adaptable as algorithms for the complete range. Fuel thermal performance is described by the HEDL SIEX model. Cladding damage and total deformation are determined by the GE GRO-II structural analysis code. A preliminary fuel pin performance model for analysis of (U, P/sub U/)O 2 pins in the COROPT core conceptual design system has been constructed by combining the key elements of SIEX and GRO-II. This memo describes the resulting pin performance model and its interfacing with COROPT system. Some exemplary results are presented

  19. Self-organized critical behavior in pinned flux lattices

    International Nuclear Information System (INIS)

    Pla, O.; Nori, F.

    1991-01-01

    We study the response of pinned fluxed lattices, under small perturbations in the driving force, below and close to the pinning-depinning transition. For driving Lorentz forces below F c (the depinning force at which the whole flux lattice slides), the system has instabilities against small force increases, with a power-law distribution characteristic of self-organized criticality. Specifically, D(d)∼d -1,3 , where d is the displacement of a flux line after a very small force increase. We also study the initial stages of the motion of the lattice once the driving force overcomes the pinning forces

  20. Fabrication of oxide dispersion strengthened ferritic clad fuel pins

    International Nuclear Information System (INIS)

    Zirker, L.R.; Bottcher, J.H.; Shikakura, S.; Tsai, C.L.

    1991-01-01

    A resistance butt welding procedure was developed and qualified for joining ferritic fuel pin cladding to end caps. The cladding are INCO MA957 and PNC ODS lots 63DSA and 1DK1, ferritic stainless steels strengthened by oxide dispersion, while the end caps are HT9 a martensitic stainless steel. With adequate parameter control the weld is formed without a residual melt phase and its strength approaches that of the cladding. This welding process required a new design for fuel pin end cap and weld joint. Summaries of the development, characterization, and fabrication processes are given for these fuel pins. 13 refs., 6 figs., 1 tab

  1. Inverse crystallization if Abrikosov vortex system at periodic pinning

    CERN Document Server

    Zyubin, M V; Kashurnikov, V A

    2002-01-01

    The vortex system in the quasi-two-dimensional HTSC plate is considered in the case of the periodic pinning. The M(H) magnetization curves by various values of the external magnetic field and different temperatures are calculated through the Monte Carlo method. It is shown that in the case of the periodic pinning the crystallization of the vortex system is possible by the temperature increase. A number of peculiarities conditioned by the impact of the pinning centers periodic lattice are identified on the magnetization curves. The pictures of the vortex distribution corresponding to various points on the M(H) curve are obtained

  2. Analyzing the use of pins in safety bearings

    DEFF Research Database (Denmark)

    da Fonseca, Cesar A. L. L.; Weber, Hans I.; Fleischer, Philip F.

    2015-01-01

    A new concept for safety bearings is analyzed: useful in emergency situations, it shall protect the bearing from destruction by the use of pins which impact with a disc, both capable of good energy dissipation. Results of work in progress are presented by validating partial stages......–Kutta method is validated with experimental results. Simulations of rotor orbits due to the impact condition are analyzed and compared to data obtained from the experiment giving a good perspective on the use of pins. The contact interaction between rotor and pins uses an elastic-dissipative model. In addition...

  3. How Helpful is Colour-Cueing of PIN Entry?

    OpenAIRE

    Renaud, Karen; Ramsay, Judith

    2014-01-01

    21st Century citizens are faced with the need to remember numbers of PINs (Personal Identification Numbers) in order to do their daily business, and they often have difficulties due to human memory limitations. One way of helping them could be by providing cues during the PIN entry process. The provision of cues that would only be helpful to the PIN owner is challenging because the cue should only make sense to the legitimate user, and not to a random observer. In this paper we report on an e...

  4. Discovery of novel selenium derivatives as Pin1 inhibitors by high-throughput screening

    International Nuclear Information System (INIS)

    Subedi, Amit; Shimizu, Takeshi; Ryo, Akihide; Sanada, Emiko; Watanabe, Nobumoto; Osada, Hiroyuki

    2016-01-01

    Peptidyl prolyl cis/trans isomerization by Pin1 regulates various oncogenic signals during cancer progression, and its inhibition through multiple approaches has established Pin1 as a therapeutic target. However, lack of simplified screening systems has limited the discovery of potent Pin1 inhibitors. We utilized phosphorylation-dependent binding of Pin1 to its specific substrate to develop a screening system for Pin1 inhibitors. Using this system, we screened a chemical library, and identified a novel selenium derivative as Pin1 inhibitor. Based on structure-activity guided chemical synthesis, we developed more potent Pin1 inhibitors that inhibited cancer cell proliferation. -- Highlights: •Novel screening for Pin1 inhibitors based on Pin1 binding is developed. •A novel selenium compound is discovered as Pin1 inhibitor. •Activity guided chemical synthesis of selenium derivatives resulted potent Pin1 inhibitors.

  5. A PWR Thorium Pin Cell Burnup Benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Kevan Dean; Zhao, X.; Pilat, E. E; Hejzlar, P.

    2000-05-01

    As part of work to evaluate the potential benefits of using thorium in LWR fuel, a thorium fueled benchmark comparison was made in this study between state-of-the-art codes, MOCUP (MCNP4B + ORIGEN2), and CASMO-4 for burnup calculations. The MOCUP runs were done individually at MIT and INEEL, using the same model but with some differences in techniques and cross section libraries. Eigenvalue and isotope concentrations were compared on a PWR pin cell model up to high burnup. The eigenvalue comparison as a function of burnup is good: the maximum difference is within 2% and the average absolute difference less than 1%. The isotope concentration comparisons are better than a set of MOX fuel benchmarks and comparable to a set of uranium fuel benchmarks reported in the literature. The actinide and fission product data sources used in the MOCUP burnup calculations for a typical thorium fuel are documented. Reasons for code vs code differences are analyzed and discussed.

  6. Pinning Control Strategy of Multicommunity Structure Networks

    Directory of Open Access Journals (Sweden)

    Chao Ding

    2017-01-01

    Full Text Available In order to investigate the effects of community structure on synchronization, a pinning control strategy is researched in a class of complex networks with community structure in this paper. A feedback control law is designed based on the network community structure information. The stability condition is given and proved by using Lyapunov stability theory. Our research shows that as to community structure networks, there being a threshold hT≈5, when coupling strength bellows this threshold, the stronger coupling strength corresponds to higher synchronizability; vice versa, the stronger coupling strength brings lower synchronizability. In addition the synchronizability of overlapping and nonoverlapping community structure networks was simulated and analyzed; while the nodes were controlled randomly and intensively, the results show that intensive control strategy is better than the random one. The network will reach synchronization easily when the node with largest betweenness was controlled. Furthermore, four difference networks’ synchronizability, such as Barabási-Albert network, Watts-Strogatz network, Erdös-Rényi network, and community structure network, are simulated; the research shows that the community structure network is more easily synchronized under the same control strength.

  7. Ideal glass transitions by random pinning

    Science.gov (United States)

    Cammarota, Chiara; Biroli, Giulio

    2012-01-01

    We study the effect of freezing the positions of a fraction c of particles from an equilibrium configuration of a supercooled liquid at a temperature T. We show that within the random first-order transition theory pinning particles leads to an ideal glass transition for a critical fraction c = cK(T) even for moderate supercooling; e.g., close to the Mode-Coupling transition temperature. First we derive the phase diagram in the T - c plane by mean field approximations. Then, by applying a real-space renormalization group method, we obtain the critical properties for |c - cK(T)| → 0, in particular the divergence of length and time scales, which are dominated by two zero-temperature fixed points. We also show that for c = cK(T) the typical distance between frozen particles is related to the static point-to-set length scale of the unconstrained liquid. We discuss what are the main differences when particles are frozen in other geometries and not from an equilibrium configuration. Finally, we explain why the glass transition induced by freezing particles provides a new and very promising avenue of research to probe the glassy state and ascertain, or disprove, the validity of the theories of the glass transition. PMID:22623524

  8. Dynamic behaviour of FBR fuel pin bundles

    International Nuclear Information System (INIS)

    Martin, P.H.; Van Dorsselaere, J.P.; Ravenet, A.

    1990-01-01

    A programme of shock tests on a fast neutron reactor subassembly model (SPX1 geometry) including a complete bundle of fuel pins (dummy elements) is being carried out in the BELIER test facility at Cadarache. The purpose of these tests is: to determine the distribution of dynamic forces applied to the fuel rod clads under the impact conditions encountered in a reactor during a earthquake; to reduce as much as possible the conservatism of the methods presently used for the calculation of those forces. The test programme, now being completed, consists of the following steps: impacts on the mock-up in air with an non-compact bundle (situation of the subassembly at beginning of life (BOL) with clearances within the bundle); impacts under the same conditions but with fluid (water) in the subassembly; impacts on the mock-up in air and with a compacted bundle (simulating the conditions of an end-of-life (EOL) bundle with no clearance within the bundle). The accelerations studied in these tests cover the range encountered in design calculations for the subassembly frequencies in beam mode. (author)

  9. Transverse pinning versus intramedullary pinning in fifth metacarpal's neck fractures: A randomized controlled study with patient-reported outcome.

    Science.gov (United States)

    Galal, Sherif; Safwat, Wael

    2017-01-01

    The 5th metacarpal fractures accounts for 38% of all hand fractures given that the neck is the weakest point in metacarpals, so neck fracture is the most common metacarpal fracture. Surgical fixation is also advocated for such fractures to prevent mal-rotation of the little finger which will lead to fingers overlap in a clenched fist. Various methods are available for fixation of such fractures, like intramedullary & transverse pinning. There are very few reports in the literature comparing both techniques. Authors wanted to compare outcomes and complications of transverse pinning versus intramedullary pinning in fifth metacarpal's neck fractures. A single-center, parallel group, prospective, randomized study was conducted at an academic Level 1 Trauma Center from October 2014 to December 2016. A total of 80 patients with 5th metacarpal's neck fractures were randomized to pinning using either transverse pinning (group A) or intramedullary pinning (group B). Patients were assessed clinically on range of motion, patient-reported outcome using the Quick-DASH (Disabilities of the Arm, Shoulder, and Hand) questionnaire & radiographically. Two blinded observers assessed outcomes. At final follow up for each patient (12 months) the statistically significant differences were observed in operative time, the transverse pinning group showed shorter operative time, as well as complication rate as complications were observed only in intramedullary pinning group. No differences were found in range of motion or the Quick -DASH score. Both techniques are equally safe and effective treatment option for 5th metacarpal's neck fractures. The only difference was shorter operative time & less incidence of complications in transverse pinning group. Level II, Therapeutic study.

  10. Buried oxide layer in silicon

    Science.gov (United States)

    Sadana, Devendra Kumar; Holland, Orin Wayne

    2001-01-01

    A process for forming Silicon-On-Insulator is described incorporating the steps of ion implantation of oxygen into a silicon substrate at elevated temperature, ion implanting oxygen at a temperature below 200.degree. C. at a lower dose to form an amorphous silicon layer, and annealing steps to form a mixture of defective single crystal silicon and polycrystalline silicon or polycrystalline silicon alone and then silicon oxide from the amorphous silicon layer to form a continuous silicon oxide layer below the surface of the silicon substrate to provide an isolated superficial layer of silicon. The invention overcomes the problem of buried isolated islands of silicon oxide forming a discontinuous buried oxide layer.

  11. Experience on 3D silicon sensors for ATLAS IBL

    International Nuclear Information System (INIS)

    Darbo, G.

    2015-01-01

    3D silicon sensors, where plasma micro-machining is used to etch deep narrow apertures in the silicon substrate to form electrodes of PIN junctions, represent possible solutions for inner pixel layers of the tracking detectors in high energy physics experiments. This type of sensors has been developed for the Insertable B-Layer (IBL), an additional pixel layer that has been installed in ATLAS during the present shutdown of the LHC collider at CERN. It is presented here the experience in designing, testing and qualifying sensors and detector modules that have been used to equip part of the IBL. Based on the gained experience with 3D silicon sensors for the ATLAS IBL, we discuss possible new developments for the upgrade of ATLAS and CMS at the high-luminosity LHC (HL-LHC)

  12. Two gamma dose evaluation methods for silicon semiconductor detector

    International Nuclear Information System (INIS)

    Chen Faguo; Jin Gen; Yang Yapeng; Xu Yuan

    2011-01-01

    Silicon PIN diodes have been widely used as personal and areal dosimeters because of their small volume, simplicity and real-time operation. However, because silicon is neither a tissue-equivalent nor an air-equivalent material, an intrinsic disadvantage for silicon dosimeters is that a significant over-response occurs at low-energy region, especially below 200 keV. Using a energy compensation filter to flatten the energy response is one method overcoming this disadvantage. But for dose compensation method, the estimated dose depends only on the number of the detector pulses. So a weight function method was introduced to evaluate gamma dose, which depends on pulse number as well as its amplitude. (authors)

  13. Characterization of Silicon Photomultiplier Detectors using Cosmic Radiation

    Science.gov (United States)

    Zavala, Favian; Castro, Juan; Niduaza, Rexavalmar; Wedel, Zachary; Fan, Sewan; Ritt, Stefan; Fatuzzo, Laura

    2014-03-01

    The silicon photomultiplier light detector has gained a lot of attention lately in fields such as particle physics, astrophysics, and medical physics. Its popularity stems from its lower cost, compact size, insensitivity to magnetic fields, and its excellent ability to distinguish a quantized number of photons. They are normally operated at room temperature and biased above their breakdown voltages. As such, they may also exhibit properties that may hinder their optimal operation which include a thermally induced high dark count rate, after pulse effects, and cross talk from photons in nearby pixels. At this poster session, we describe our data analysis and our endeavor to characterize the multipixel photon counter (MPPC) detectors from Hamamatsu under different bias voltages and temperature conditions. Particularly, we describe our setup which uses cosmic rays to induce scintillation light delivered to the detector by wavelength shifting optical fibers and the use of a fast 1 GHz waveform sampler, the domino ring sampler (DRS4) digitizer board. Department of Education grant number P031S90007.

  14. CCD developed for scientific application by Hamamatsu

    CERN Document Server

    Miyaguchi, K; Dezaki, J; Yamamoto, K

    1999-01-01

    We have developed CCDs for scientific applications that feature a low readout noise of less than 5 e-rms and low dark current of 10-25 pA/cm sup 2 at room temperature. CCDs with these characteristics will prove extremely useful in applications such as spectroscopic measurement and dental radiography. In addition, a large-area CCD of 2kx4k pixels and 15 mu m square pixel size has recently been completed for optical use in astronomical observations. Applications to X-ray astronomy require the most challenging device performance in terms of deep depletion, high CTE, and focal plane size, among others. An abuttable X-ray CCD, having 1024x1024 pixels and 24 mu m square pixel size, is to be installed in an international space station (ISS). We are now striving to achieve the lowest usable cooling temperature by means of a built-in TEC with limited power consumption. Details on the development status are described in this report. We would also like to present our future plans for a large active area and deep depleti...

  15. Close Proximity Robotic Maneuvering through Flux Pinning Manipulation

    Data.gov (United States)

    National Aeronautics and Space Administration — Non-contacting actuation technology like flux pinning has never been demonstrated in space. The development of a nonphysical joint is critical for maneuvers such as...

  16. Pin failure modeling of the A series CABRI tests

    International Nuclear Information System (INIS)

    Young, M.F.; Portugal, J.L.

    1978-01-01

    The EXPAND pin fialure model, a research tool designed to model pin failure under prompt burst conditions, has been used to predict failure conditions for several of the A series CABRI tests as part of the United States participation in the CABRI Joint Project. The Project is an international program involving France, Germany, England, Japan, and the United States and has the goal of obtaining experimental data relating to the safety of LMFBR's. The A series, designed to simulate high ramp rate TOP conditions, initially utilizes single, fresh UO 2 pins of the PHENIX type in a flowing sodium loop. The pins are preheated at constant power in the CABRI reactor to establish steady state conditions (480 w/cm at the axial peak) and then subjected to a power pulse of 14 ms to 24 ms duration

  17. Progress in fuel pin modelling in the USA

    Energy Technology Data Exchange (ETDEWEB)

    Stephen, J D; Biancheria, A; Leibnitz, D; O' Reilly, B D; Liu, Y Y; Labar, M P; Gneiting, B C [General Electric Company, Sunnyvale, CA (United States)

    1979-12-01

    In the USA, the focus for theoretical fuel pin modeling is the LIFE system. This system of codes, algorithms, criteria and analysis guidelines is intended to provide a common basis for communication amongst the development groups, a reference set of analysis guidelines for design, and eventually a consensus on the state-of-the-art for licensing. The technical objective is to predict the effect of design options on fuel pin performance limits, which include fuel temperature, pin deformation and cladding breach during normal operation and design basis transients. The mechanistic approach to modeling is taken in LIFE to the extent possible. That is, the approach is to describe the key phenomena in sufficient detail to provide a fundamental understanding of their synergistic effect on the fuel pin performance limits.

  18. The treatment of burnable poison pins in LWRWIMS

    International Nuclear Information System (INIS)

    Halsall, M.J.

    1982-12-01

    This report describes an investigation into the modelling approximations normally made when the LWR lattice code LWRWIMS is used for design calculations on assemblies containing burnable poison pins. Parameters investigated include energy group structure, intervals between calculations in MWd/te and spatial subdivision of the poison pins. An estimate is made of the effect of using pin-cell smearing with diffusion theory for the assembly geometry, instead of a more exact heterogeneous transport theory calculation. The influence on reactivity of the minor gadolinium isotopes 152, 154, 156, 158 and 160 in a poison pin dominated by the isotopes 155 and 157 is presented, and finally, recommendations on the use of LWRWIMS for this type of calculation are made. (author)

  19. PIN architecture for ultrasensitive organic thin film photoconductors.

    Science.gov (United States)

    Jin, Zhiwen; Wang, Jizheng

    2014-06-17

    Organic thin film photoconductors (OTFPs) are expected to have wide applications in the field of optical communications, artificial vision and biomedical sensing due to their great advantages of high flexibility and low-cost large-area fabrication. However, their performances are not satisfactory at present: the value of responsivity (R), the parameter that measures the sensitivity of a photoconductor to light, is below 1 AW(-1). We believe such poor performance is resulted from an intrinsic self-limited effect of present bare blend based device structure. Here we designed a PIN architecture for OTFPs, the PIN device exhibits a significantly improved high R value of 96.5 AW(-1). The PIN architecture and the performance the PIN device shows here should represent an important step in the development of OTFPs.

  20. Investigation of pinning in MgB2 superconductors

    International Nuclear Information System (INIS)

    Mohammad, S.; Reissner, M.; Steiner, W.; Bauer, E.; Giovannini, M.

    2006-01-01

    Full text: The pinning behaviour of bulk MgB 2 superconductors is peculiar in many respects. Pinning seems to be stronger than in classical high T C materials and there seems to be no weak link problem in these compounds, giving hope to produce bulk samples and wires with current densities appropriate for technical applications. But, although many studies concerning the pinning behaviour in this compound appeared in recent years, the results are still contradictory. In the present work we present results of an investigation of the pinning behaviour by magnetic relaxation measurements of three MgB 2 samples: a pure one, a sample with 8 at% Al substitution and a sample with 10 wt% of SiC admixture. A comparison of different analyses methods is given. (author)

  1. SP-100 Fuel Pin Performance: Results from Irradiation Testing

    Science.gov (United States)

    Makenas, Bruce J.; Paxton, Dean M.; Vaidyanathan, Swaminathan; Marietta, Martin; Hoth, Carl W.

    1994-07-01

    A total of 86 experimental fuel pins with various fuel, liner, and cladding candidate materials have been irradiated in the Experimental Breeder Reactor-II (EBR-II) and the Fast Flux Test Facility (FFTF) reactor as part of the SP-100 fuel pin irradiation testing program. Postirradiation examination results from these fuel pins are key in establishing performance correlations and demonstrating the lifetime and safety of the reactor fuel system. This paper provides a brief description of the in-reactor fuel pin tests and presents the most recent irradiation data on the performance of wrought rhenium (Re) liner material and high density UN fuel at goal burnup of 6 atom percent (at. %). It also provides an overview of the significant variety of other fuel/liner/cladding combinations which were irradiated as part of this program and which may be of interest to more advanced efforts.

  2. Evaluation of the performance of irradiated silicon strip sensors for the forward detector of the ATLAS Inner Tracker Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Mori, R., E-mail: riccardo.mori@physik.uni-freiburg.de [Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Allport, P.P.; Baca, M.; Broughton, J.; Chisholm, A.; Nikolopoulos, K.; Pyatt, S.; Thomas, J.P.; Wilson, J.A. [School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT (United Kingdom); Kierstead, J.; Kuczewski, P.; Lynn, D. [Brookhaven National Laboratory, Physics Department and Instrumentation Division, Upton, NY 11973-5000 (United States); Arratia-Munoz, M.I.; Hommels, L.B.A. [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Ullan, M.; Fleta, C.; Fernandez-Tejero, J. [Centro Nacional de Microelectronica (IMB-CNM, CSIC), Campus UAB-Bellaterra, 08193 Barcelona (Spain); Bloch, I.; Gregor, I.M.; Lohwasser, K. [DESY, Notkestrasse 85, 22607 Hambrug (Germany); and others

    2016-09-21

    The upgrade to the High-Luminosity LHC foreseen in about ten years represents a great challenge for the ATLAS inner tracker and the silicon strip sensors in the forward region. Several strip sensor designs were developed by the ATLAS collaboration and fabricated by Hamamatsu in order to maintain enough performance in terms of charge collection efficiency and its uniformity throughout the active region. Of particular attention, in the case of a stereo-strip sensor, is the area near the sensor edge where shorter strips were ganged to the complete ones. In this work the electrical and charge collection test results on irradiated miniature sensors with forward geometry are presented. Results from charge collection efficiency measurements show that at the maximum expected fluence, the collected charge is roughly halved with respect to the one obtained prior to irradiation. Laser measurements show a good signal uniformity over the sensor. Ganged strips have a similar efficiency as standard strips.

  3. Behavior of a bundle of fast fuel pins under irradiation

    International Nuclear Information System (INIS)

    Marbach, G.; Millet, P.; Robert, J.; Languille, A.

    1979-01-01

    In the French design of fuel elements for fast reactors, great deformation of pins can bring about interaction with the hexagonal tube through the spacer wires. The change in such bundles is described here when the diameter of the cladding increases and the outcome of this reaction (bending and ovalization of pins) is calculated with a simplified model. It is shown that the results achieved agree well with the experimental observations [fr

  4. Pin and roller attachment system for ceramic blades

    Science.gov (United States)

    Shaffer, J.E.

    1995-07-25

    In a turbine, a plurality of blades are attached to a turbine wheel by way of a plurality of joints which form a rolling contact between the blades and the turbine wheel. Each joint includes a pin and a pair of rollers to provide rolling contact between the pin and an adjacent pair of blades. Because of this rolling contact, high stress scuffing between the blades and the turbine wheel reduced, thereby inhibiting catastrophic failure of the blade joints. 3 figs.

  5. Cyclic movement pin mechanism for controlling a nuclear reactor

    International Nuclear Information System (INIS)

    Joly, J.G.; Martin, Jean.

    1981-01-01

    This invention concerns a recurring movement pin mechanism for controlling a nuclear reactor by shifting a neutron absorbing assembly, vertically mobile in the nuclear reactor, to adjust the power and for emergency shut-down. This mechanism ensures a continuous movement and accurate shut-down at any level of the travel height of the absorbing assembly in the core. It also prevents the impacts of the pivoting pins in the control rod slots [fr

  6. Theory of activated glassy dynamics in randomly pinned fluids

    Science.gov (United States)

    Phan, Anh D.; Schweizer, Kenneth S.

    2018-02-01

    We generalize the force-level, microscopic, Nonlinear Langevin Equation (NLE) theory and its elastically collective generalization [elastically collective nonlinear Langevin equation (ECNLE) theory] of activated dynamics in bulk spherical particle liquids to address the influence of random particle pinning on structural relaxation. The simplest neutral confinement model is analyzed for hard spheres where there is no change of the equilibrium pair structure upon particle pinning. As the pinned fraction grows, cage scale dynamical constraints are intensified in a manner that increases with density. This results in the mobile particles becoming more transiently localized, with increases of the jump distance, cage scale barrier, and NLE theory mean hopping time; subtle changes of the dynamic shear modulus are predicted. The results are contrasted with recent simulations. Similarities in relaxation behavior are identified in the dynamic precursor regime, including a roughly exponential, or weakly supra-exponential, growth of the alpha time with pinning fraction and a reduction of dynamic fragility. However, the increase of the alpha time with pinning predicted by the local NLE theory is too small and severely so at very high volume fractions. The strong deviations are argued to be due to the longer range collective elasticity aspect of the problem which is expected to be modified by random pinning in a complex manner. A qualitative physical scenario is offered for how the three distinct aspects that quantify the elastic barrier may change with pinning. ECNLE theory calculations of the alpha time are then presented based on the simplest effective-medium-like treatment for how random pinning modifies the elastic barrier. The results appear to be consistent with most, but not all, trends seen in recent simulations. Key open problems are discussed with regard to both theory and simulation.

  7. Incidence and risk factors for pin tract infection in external fixation of ...

    African Journals Online (AJOL)

    Incidence and risk factors for pin tract infection in external fixation of fractures ... for pin tract infection, there were 93 pins scored grade 1, 32 pins grade 2, 15 ... The incidence increased from 20.5% in closed fractures to 75.9% in open fractures.

  8. Vortex Avalanches with Periodic Arrays of Pinning Sites

    Science.gov (United States)

    Abbas, J.; Heckel, T.; Kakalios, J.

    2001-03-01

    Numerical simulations by Nori and co-workers of dynamical phase transitions for magnetic vortices in type II superconductors when the defects which act as pinning sites are arranged in a periodic array have found a dramatic non-linear relationship between vortex voltage and driving current.2,4 In order to experimentally test the predictions of these simulations, a macroscopic physical analog of an array of flux vortices in the presense of an ordered lattice of pinning sites has been constructed. This simple table-top experimental system consists of conventional household magnets, arranged in an ordered grid (serving as the lattice of fixed pinning centers). A plexiglass sheet is positioned above these fixed magnets, and another collection of magnets (representing the magnetic flux vortices), oriented so that they are attracted to the fixed magnets are placed on top of the sheet. The entire apparatus is then tilted to a given angle (the analog of the driving voltage) and the velocity of the avalanching magnets is recorded using the induced voltage in a pick-up coil. By varying the ratio of movable magnets to fixed pinning magnets, the filling fraction can be adjusted, as can the pinning strength, by adjusting the separation of the plexiglass sheet between the fixed and movable magnets. The velocity of the avalanching magnets as the filling fraction is varied displays a jamming transition, with a non-trivial dependence on the pinning strength of the lattice of fixed magnets below the sheet.

  9. JMCT Monte Carlo simulation analysis of full core PWR Pin-By-Pin and shielding

    International Nuclear Information System (INIS)

    Deng, L.; Li, G.; Zhang, B.; Shangguan, D.; Ma, Y.; Hu, Z.; Fu, Y.; Li, R.; Hu, X.; Cheng, T.; Shi, D.

    2015-01-01

    This paper describes the application of the JMCT Monte Carlo code to the simulation of Kord Smith Challenge H-M model, BEAVRS model and Chinese SG-III model. For H-M model, the 6.3624 millions tally regions and the 98.3 billion neutron histories do. The detailed pin flux and energy deposition densities obtain. 95% regions have less 1% standard deviation. For BEAVRS model, firstly, we performed the neutron transport calculation of 398 axial planes in the Hot Zero Power (HZP) status. Almost the same results with MC21 and OpenMC results are achieved. The detailed pin-power density distribution and standard deviation are shown. Then, we performed the calculation of ten depletion steps in 30 axial plane cases. The depletion regions exceed 1.5 million and 12,000 processors uses. Finally, the Chinese SG-III laser model is simulated. The neutron and photon flux distributions are given, respectively. The results show that the JMCT code well suits for extremely large reactor and shielding simulation. (author)

  10. A polygonal nodal SP3 method for whole core Pin-by-Pin neutronics calculation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yunzhao; Wu, Hongchun; Cao, Liangzhi, E-mail: xjtulyz@gmail.com, E-mail: hongchun@mail.xjtu.edu.cn, E-mail: caolz@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi' an Jiaotong University, Shaanxi (China)

    2011-07-01

    In this polygonal nodal-SP3 method, neutron transport equation is transformed by employing an isotropic SP3 method into two coupled equations that are both in the same mathematic form with the diffusion equation, and then a polygonal nodal method is proposed to solve the two coupled equations. In the polygonal nodal method, adjacent nodes are coupled through partial currents, and a nodal response matrix between incoming and outgoing currents is obtained by expanding detailed nodal flux distribution into a sum of exponential functions. This method avoids the transverse integral technique, which is widely used in regular nodal method and can not be used in triangular geometry because of the mathematical singularity. It is demonstrated by the numerical results of the test problems that the k{sub eff} and power distribution agree well with other codes, the triangular nodal-SP3 method appears faster, and that whole core pin-by-pin transport calculation with fine meshes is feasible after parallelization and acceleration. (author)

  11. Development of modeling tools for pin-by-pin precise reactor simulation

    International Nuclear Information System (INIS)

    Ma Yan; Li Shu; Li Gang; Zhang Baoyin; Deng Li; Fu Yuanguang

    2013-01-01

    In order to develop large-scale transport simulation and calculation method (such as simulation of whole reactor core pin-by-pin problem), the Institute of Applied Physics and Computational Mathematics developed the neutron-photon coupled transport code JMCT and the toolkit JCOGIN. Creating physical calculation model easily and efficiently can essentially reduce problem solving time. Currently, lots of visual modeling programs have been developed based on different CAD systems. In this article, the developing idea of a visual modeling tool based on field oriented development was introduced. Considering the feature of physical modeling, fast and convenient operation modules were developed. In order to solve the storage and conversion problems of large scale models, the data structure and conversional algorithm based on the hierarchical geometry tree were designed. The automatic conversion and generation of physical model input file for JMCT were realized. By using this modeling tool, the Dayawan reactor whole core physical model was created, and the transformed file was delivered to JMCT for transport calculation. The results validate the correctness of the visual modeling tool. (authors)

  12. Process effects on leakage current of Si-PIN neutron detectors with porous microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Baoning; Zhao, Kangkang; Yang, Taotao [Beijing University of Technology, Chaoyang District, Pingleyuan 100, 100124 Beijing (China); Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Ruoshui Road 398, 215123 Suzhou (China); Jiang, Yong; Fan, Xiaoqiang [Institute of Nuclear Physics and Chemistry, CAEP, Mianshan Road 64, 621900 Mianyang (China); Lu, Min [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Ruoshui Road 398, 215123 Suzhou (China); Han, Jun [Beijing University of Technology, Chaoyang District, Pingleyuan 100, 100124 Beijing (China)

    2017-06-15

    Using the technique of Microfabrication, such as deep silicon dry etching, lithography, etc. Si-PIN neutron detectors with porous microstructure have been successfully fabricated. In order to lower the leakage current, the key fabrication processes, including the Al windows opening, deep silicon etching and the porous side wall smoothing, have been optimized. The cross-section morphology and current-voltage characteristics have been measured to evaluate the microfabrication processes. With the optimized conditions presented by the measurements, a neutron detector with a leakage current density of 2.67 μA cm{sup -2} at a bias of -20 V is obtained. A preliminary neutron irradiation test with {sup 252}Cf neutron source has also been carried out. The neutron irradiation test shows that the neutron detection efficiency of the microstructured neutron detectors is almost 3.6 times higher than that of the planar ones. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Repeat biopsy in patients with initial diagnosis of PIN; La biopsia ripetuta nei pazienti con diagnosi iniziale di PIN

    Energy Technology Data Exchange (ETDEWEB)

    De Matteis, Massimo [Azienda Ospedaliera Policlinico S. Orsola-Malpighi, Bologna (Italy). UO Radiologia Albertoni; Poggi, Cristina; De Martino, Antonietta; Pavlica, Pietro [Azienda Ospedaliera Policlinico S. Orsola-Malpighi, Bologna (Italy). UO Radiologia Palagi, Dipartimento area radiologica; Corti, Barbara [Azienda Ospedaliera Policlinico S. Orsola-Malpighi, Bologna (Italy). UO Anatomia ed istologia patologica, Dipartimento oncologico ed ematologico; Barozzi, Libero [Azienda Ospedaliera Policlinico S. Orsola-Malpighi, Bologna (Italy). UO Radiologia d' urgenza, Dipartimento emergenze ed accettazione

    2005-09-15

    Purpose. Prostatic intra-epithelial neoplasia (PIN) is considered a pre-malignant lesion and the main precursor of invasive prostatic adenocarcinoma. A PIN diagnosis established by prostate needle biopsy poses a difficult clinical management. problem. We retrospectively reviewed our three-year experience in order to identify criteria for referring patients to repeat biopsy. Materials and methods. We reviewed the repeat biopsy records of 72 patients in whom PIN had been detected on initial US-guided needle biopsy of the prostate. All the patients had a minimum of 6 biopsy cores taken, and they all had PSA > 4 ng/ml. Results. Adenocarcinoma was detected in 15 patients out of 50 (30%) with an initial diagnosis of low-grade PIN and in 10 patients out of 22 (45.4%) with high grade PIN, in 7 out of 18 (39%) in whom PSA levels had decreased during the observation interval, in 16 patients out of 46 (35%) in whom the PSA had increased and in 2 patients out of 8 (25%) with stable PSA. Conclusions. Our results seem to confirm that PIN can be considered a precursor of prostatic adenocarcinoma or a histological alteration often associated with it. Patients with low-grade PIN and particularly those with high-grade PIN should be regularly subjected to repeat biopsy at short intervals due to the high frequency of the final diagnosis of carcinoma. No agreement has been reached on the time interval between the first and the second biopsy. The PSA changes during the observation period are not a statistically significant parameter to suggest the repetition of prostatic biopsy. [Italian] Scopo. La neoplasia prostatica intraepiteliale (PIN) e considerata una lesione premaligna ed il precursore principale dell'adenocarcinoma prostatico infiltrante. La diagnosi di PIN ottenuta con l'agobiopsia della prostata rappresenta un difficile problema gestionale clinico. In una valutazione retrospettiva della nostra esperienza di 3 anni si e cercato di individuare i criteri che possano

  14. Interplay between collective pinning and artificial defects on domain wall propagation in Co/Pt multilayers

    International Nuclear Information System (INIS)

    Rodriguez-Rodriguez, G; Hierro-Rodriguez, A; Perez-Junquera, A; Montenegro, N; Alameda, J M; Velez, M; Menendez, J L; Ravelosona, D

    2010-01-01

    The interplay between collective pinning on intrinsic structural defects and artificial pinning at a patterned hole is studied in magnetic multilayers with perpendicular anisotropy. The pinning strength of a patterned hole is measured through its efficiency to stop domain wall (DW) propagation into a consecutive unpatterned nanowire section (using antisymmetric magnetoresistance to detect the direction of DW propagation) whereas collective pinning is characterized by the field dependence of DW velocity. Close to room temperature, collective pinning becomes weaker than artificial pinning so that pinning at the hole compensates nucleation-pad geometry, blocking DW propagation across the nanowire.

  15. Fuel pin bowing and related investigation of WWER-440 control rod influence on power release inside of neighbouring fuel pins

    International Nuclear Information System (INIS)

    Mikus, J.

    2005-01-01

    The purpose of this work consists in investigation of the WWER-440 control rod (CR) influence on space power distribution, especially from viewpoint of the values and gradient occurrence that could result in static and cyclic loads with some consequences, e.g. fuel pin bowing. As known, CR can cause power peaks in periphery fuel pins of adjacent operating assemblies because of the butt joint design of the absorbing adapter to the CR fuel part, that is, presence of the water cavity resulting in a flash up of thermal neutrons. As a consequence, beside well-known peaks in axial power distribution, above power gradients can occur inside of mentioned fuel pins. Because of complicated geometry and material composition of the CR, the detailed calculations concerning both above phenomena are complicated, too. Therefore it is useful to acquire appropriate experimental data to investigate mentioned influence and compare them with calculations. Since detailed power distributions cannot be obtained in the NPP, needed information is provided by means of experiments on research reactors. In case of measurements inside of fuel pins, special (e.g. track) detectors placed between fuel pellets are used. Such works are relatively complicated and time consuming, therefore an evaluation based on mathematical modelling and numerical approximation was proposed by means of that, and using measured power release in some selected fuel pins, information about power release inside of one of these fuel pins, can be obtained. For this purpose, an experiment on light water, zero-power research reactor LR-0 was realized and axial power distribution measurements were performed in a WWER-440 type core near to an authentic CR model. Application of the above evaluation method is demonstrated on one ''investigated'' fuel pin neighbouring CR by means of following results: 1. Axial power distribution inside of investigated fuel pin in two opposite positions on its pellets surface that are situated to

  16. Correction of measured Gamma-Knife output factors for angular dependence of diode detectors and PinPoint ionization chamber.

    Science.gov (United States)

    Hršak, Hrvoje; Majer, Marija; Grego, Timor; Bibić, Juraj; Heinrich, Zdravko

    2014-12-01

    Dosimetry for Gamma-Knife requires detectors with high spatial resolution and minimal angular dependence of response. Angular dependence and end effect time for p-type silicon detectors (PTW Diode P and Diode E) and PTW PinPoint ionization chamber were measured with Gamma-Knife beams. Weighted angular dependence correction factors were calculated for each detector. The Gamma-Knife output factors were corrected for angular dependence and end effect time. For Gamma-Knife beams angle range of 84°-54°. Diode P shows considerable angular dependence of 9% and 8% for the 18 mm and 14, 8, 4 mm collimator, respectively. For Diode E this dependence is about 4% for all collimators. PinPoint ionization chamber shows angular dependence of less than 3% for 18, 14 and 8 mm helmet and 10% for 4 mm collimator due to volumetric averaging effect in a small photon beam. Corrected output factors for 14 mm helmet are in very good agreement (within ±0.3%) with published data and values recommended by vendor (Elekta AB, Stockholm, Sweden). For the 8 mm collimator diodes are still in good agreement with recommended values (within ±0.6%), while PinPoint gives 3% less value. For the 4 mm helmet Diodes P and E show over-response of 2.8% and 1.8%, respectively. For PinPoint chamber output factor of 4 mm collimator is 25% lower than Elekta value which is generally not consequence of angular dependence, but of volumetric averaging effect and lack of lateral electronic equilibrium. Diodes P and E represent good choice for Gamma-Knife dosimetry. Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  17. Complications after pinning of supracondylar distal humerus fractures.

    Science.gov (United States)

    Bashyal, Ravi K; Chu, Jennifer Y; Schoenecker, Perry L; Dobbs, Matthew B; Luhmann, Scott J; Gordon, J Eric

    2009-01-01

    Supracondylar distal humerus fractures are one of the most common skeletal injuries in children. The current treatment of choice in North America is closed reduction and percutaneous pin fixation. Often surgeons leave the pins exposed beneath a cast but outside the skin. Great variation exists with respect to preoperative skin preparation, and perioperative antibiotic administration. Few data exist regarding the rate of infection and other complications. The purpose of this study is to review a large series of children to evaluate the rate of infection and other complications. A retrospective review was carried out of all patients treated at our institution over an 11-year period. A total of 622 patients were identified that were followed for a minimum of 2 weeks after pin removal. Seventeen patients had flexion-type fractures, 294 had type II fractures, and 311 had type III fractures. Seventy-four fractures (11.9%) had preoperative nerve deficits with anterior interosseous palsies being the most common (33 fractures, 5.3%). Preoperative antibiotics were given to 163 patients (26.2%). Spray and towel draping were used in 362 patients, paint and towel draping were used in 65 patients, alcohol paint and towel draping were used in 146 patients, and a full preparation and draping were used in 13 patients. The pins were left exposed under the cast in 591 fractures (95%), and buried beneath the skin in 31 fractures (5.0%). A medial pin was placed in 311 fractures with a small incision made to aid placement in 18 of these cases. The most common complication was pin migration necessitating unexpected return to the operating room for pin removal in 11 patients (1.8%). One patient developed a deep infection with septic arthritis and osteomyelitis (0.2%). Five additional patients had superficial skin infections and were treated with oral antibiotics for a total infection rate of 6 of 622 patients (1.0%). One patient ultimately had a malunion and 4 others returned to the

  18. High-performance whole core Pin-by-Pin calculation based on EFEN-SP_3 method

    International Nuclear Information System (INIS)

    Yang Wen; Zheng Youqi; Wu Hongchun; Cao Liangzhi; Li Yunzhao

    2014-01-01

    The EFEN code for high-performance PWR whole core pin-by-pin calculation based on the EFEN-SP_3 method can be achieved by employing spatial parallelization based on MPI. To take advantage of the advanced computing and storage power, the entire problem spatial domain can be appropriately decomposed into sub-domains and the assigned to parallel CPUs to balance the computing load and minimize communication cost. Meanwhile, Red-Black Gauss-Seidel nodal sweeping scheme is employed to avoid the within-group iteration deterioration due to spatial parallelization. Numerical results based on whole core pin-by-pin problems designed according to commercial PWRs demonstrate the following conclusions: The EFEN code can provide results with acceptable accuracy; Communication period impacts neither the accuracy nor the parallel efficiency; Domain decomposition methods with smaller surface to volume ratio leads to greater parallel efficiency; A PWR whole core pin-by-pin calculation with a spatial mesh 289 × 289 × 218 and 4 energy groups could be completed about 900 s by using 125 CPUs, and its parallel efficiency is maintained at about 90%. (authors)

  19. Multilevel parallel strategy on Monte Carlo particle transport for the large-scale full-core pin-by-pin simulations

    International Nuclear Information System (INIS)

    Zhang, B.; Li, G.; Wang, W.; Shangguan, D.; Deng, L.

    2015-01-01

    This paper introduces the Strategy of multilevel hybrid parallelism of JCOGIN Infrastructure on Monte Carlo Particle Transport for the large-scale full-core pin-by-pin simulations. The particle parallelism, domain decomposition parallelism and MPI/OpenMP parallelism are designed and implemented. By the testing, JMCT presents the parallel scalability of JCOGIN, which reaches the parallel efficiency 80% on 120,000 cores for the pin-by-pin computation of the BEAVRS benchmark. (author)

  20. Development of a semiconductor neutron dosimeter with a PIN diode

    International Nuclear Information System (INIS)

    Kim, Seungho; Lee, Namho; Cho, Jaiwan; Youk, Geunuck

    2004-01-01

    When a Si PIN diode is exposed to fast neutrons, it produces displacement in Si lattice structure of the diode. Defects induced from structural dislocation become effective recombination centers for carriers which pass through the base of a PIN diode. Hence, increasing the resistivity of the diode decreases the current for the applied forward voltage. This paper involves the development of a neutron sensor based on the phenomena of the displacement effect damaged by neutron exposure. The neutron effect on the semiconductor was analyzed, and multi PIN diode arrays with various intrinsic layer (I layer) thicknesses and cross sections were fabricated. Under irradiation tests with a neutron beam, the manufactured diodes have good characteristics of linearity in a neutron irradiation experiment and give results that the increase of thickness of I layer and the decrease of the cross-section of the PIN diodes improve the sensitivity. Newly developed PIN diodes with a thicker I layer and various cross sections were retested and showed the best neutron sensitivity in the condition that the I layer thickness was similar to the length of a side of the cross-section. On the basis of two test results, final PIN diodes with a rectangular shape were manufactured and the characteristics for neutron detectors were analyzed through the neutron beam test using the on-line electronic dosimetry system. The developed PIN diode shows a good linearity to absorbed dose in the range of 0 to 1,000cGy (Tissue) and its neutron sensitivity is 13 mV/cGy at a constant current of 5 mA, that is three higher than that of similar commercially developed neutron detectors. Moreover the device shows less dependency on the orientation of the neutron beam and a considerable stability in an annealing test for a long period. (author)

  1. Fuel pin response to an overpower transient in an LMFBR

    International Nuclear Information System (INIS)

    Grosberg, A.J.; Head, J.L.

    1979-01-01

    This paper describes a method by which the ability of a whole-core code accurately to predict the time and location of the first fuel pin failures may be tested. The method involves the use of a relatively simple whole-core code to 'drive' a sophisticated fuel pin code, which is far too complex to be used within a whole-core code but which is potentially capable of modelling reliably the response of an individual fuel pin. The method cannot follow accurately the subsequent course of the transient because the simple whole-core code does not model the reactivity effects of events which may follow pin failure. The codes used were the simple whole-core code FUTURE and the fuel pin behaviour code FRUMP. The paper describes an application of the method to analyse a hypothetical LMFBR accident in which the control rods were assumed to be driven from the core at maximum speed, with all trip circuits failed. Taking 0.5% clad strain as a clad failure criterion, failure was predicted to occur at the top of the active core at about 10s into the transient. A repeat analysis, using an alternative clad yield criterion which is thought to be more realistic, indicated failure at the same position but 24s into the transient. This is after the onset of sodium boiling. Pin failure at the top of the core are likely to cause negative reactivity changes. In this hypothetical accident, pin failures are likely, therefore, to have a moderating effect on the course of the transient. (orig.)

  2. Alpha particles spectrometer with photodiode PIN; Espectrometro de particulas alfa con fotodiodo PIN

    Energy Technology Data Exchange (ETDEWEB)

    Chacon R, A.; Hernandez V, R.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidades Academicas de Estudios Nucleares e Ingenieria Electrica, Calle Cipres No. 10, Fracc. La Penuela, 09869 Zacatecas (Mexico); Ramirez G, J. [Instituto Nacional de Estadistica Geografia e Informatica, Direccion General de Innovacion y Tecnologia de Informacion, Av. Heroes de Nacozari Sur 2301, Fracc. Jardines del Parque, 20276 Aguascalientes (Mexico)], e-mail: achruiz@hotmail.com

    2009-10-15

    The radiation propagates in form of electromagnetic waves or corpuscular radiation; if the radiation energy causes ionization in environment that crosses it is considered ionizing radiation. To detect radiation several detectors types are used, if the radiation are alpha particles are used detectors proportional type or trace elements. In this work the design results, construction and tests of an alpha particles spectrometer are presented, which was designed starting from a photodiode PIN type. The system design was simulated with a code for electronic circuits. With results of simulation phase was constructed the electronic phase that is coupled to a multichannel analyzer. The resulting electronic is evaluated analyzing the electronic circuit performance before an alphas triple source and alpha radiation that produce two smoke detectors of domestic use. On the tests phase we find that the system allows obtain, in a multichannel, the pulses height spectrum, with which we calibrate the system. (Author)

  3. Silicon: electrochemistry and luminescence

    NARCIS (Netherlands)

    Kooij, Ernst Stefan

    1997-01-01

    The electrochemistry of crystalline and porous silicon and the luminescence from porous silicon has been studied. One chapter deals with a model for the anodic dissolution of silicon in HF solution. In following chapters both the electrochemistry and various ways of generating visible

  4. Generation of clusters in complex dynamical networks via pinning control

    International Nuclear Information System (INIS)

    Li Kezan; Fu Xinchu; Small, Michael

    2008-01-01

    Many real-world networks show community structure, i.e., groups (or clusters) of nodes that have a high density of links within them but with a lower density of links between them. In this paper, by applying feedback injections to a fraction of network nodes, various clusters are synchronized independently according to the community structure generated by the group partition of the network (cluster synchronization). This control is achieved by pinning (i.e. applying linear feedback control) to a subset of the network nodes. Those pinned nodes are selected not randomly but according to the topological structure of communities of a given network. Specifically, for a given group partition of a network, those nodes with direct connections between groups must be pinned in order to achieve cluster synchronization. Both the local stability and global stability of cluster synchronization are investigated. Taking the tree-shaped network and the most modular network as two particular examples, we illustrate in detail how the pinning strategy influences the generation of clusters. The simulations verify the efficiency of the pinning schemes used in this paper

  5. A Flux-Pinning Mechanism for Segment Assembly and Alignment

    Science.gov (United States)

    Gersh-Range, Jessica A.; Arnold, William R.; Peck, Mason A.; Stahl, H. Philip

    2011-01-01

    Currently, the most compelling astrophysics questions include how planets and the first stars formed and whether there are protostellar disks that contain large organic molecules. Although answering these questions requires space telescopes with apertures of at least 10 meters, such large primaries are challenging to construct by scaling up previous designs; the limited capacity of a launch vehicle bounds the maximum diameter of a monolithic primary, and beyond a certain size, deployable telescopes cannot fit in current launch vehicle fairings. One potential solution is connecting the primary mirror segments edgewise using flux-pinning mechanisms, which are analogous to non-contacting damped springs. In the baseline design, a flux-pinning mechanism consists of a magnet and a superconductor separated by a predetermined gap, with the damping adjusted by placing aluminum near the interface. Since flux pinning is possible only when the superconductor is cooled below a critical temperature, flux-pinning mechanisms are uniquely suited for cryogenic space telescopes. By placing these mechanisms along the edges of the mirror segments, a primary can be built up over time. Since flux pinning requires no mechanical deployments, the assembly process could be robotic or use some other non-contacting scheme. Advantages of this approach include scalability and passive stability.

  6. Pin1 and neurodegeneration: a new player for prion disorders?

    Directory of Open Access Journals (Sweden)

    Elisa Isopi

    2015-07-01

    Full Text Available Pin1 is a peptidyl-prolyl isomerase that catalyzes the cis/trans conversion of phosphorylated proteins at serine or threonine residues which precede a proline. The peptidyl-prolyl isomerization induces a conformational change of the proteins involved in cell signaling process. Pin1 dysregulation has been associated with some neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and Huntington's disease. Proline-directed phosphorylation is a common regulator of these pathologies and a recent work showed that it is also involved in prion disorders. In fact, prion protein phosphorylation at the Ser-43-Pro motif induces prion protein conversion into a disease-associated form. Furthermore, phosphorylation at Ser-43-Pro has been observed to increase in the cerebral spinal fluid of sporadic Creutzfeldt-Jakob Disease patients. These findings provide new insights into the pathogenesis of prion disorders, suggesting Pin1 as a potential new player in the disease. In this paper, we review the mechanisms underlying Pin1 involvement in the aforementioned neurodegenerative pathologies focusing on the potential role of Pin1 in prion disorders.

  7. Exchange anisotropy pinning of a standing spin-wave mode

    Science.gov (United States)

    Magaraggia, R.; Kennewell, K.; Kostylev, M.; Stamps, R. L.; Ali, M.; Greig, D.; Hickey, B. J.; Marrows, C. H.

    2011-02-01

    Standing spin waves in a thin film are used as sensitive probes of interface pinning induced by an antiferromagnet through exchange anisotropy. Using coplanar waveguide ferromagnetic resonance, pinning of the lowest energy spin-wave thickness mode in Ni80Fe20/Ir25Mn75 exchange-biased bilayers was studied for a range of Ir25Mn75 thicknesses. We show that pinning of the standing mode can be used to amplify, relative to the fundamental resonance, frequency shifts associated with exchange bias. The shifts provide a unique “fingerprint” of the exchange bias and can be interpreted in terms of an effective ferromagnetic film thickness and ferromagnet-antiferromagnet interface anisotropy. Thermal effects are studied for ultrathin antiferromagnetic Ir25Mn75 thicknesses, and the onset of bias is correlated with changes in the pinning fields. The pinning strength magnitude is found to grow with cooling of the sample, while the effective ferromagnetic film thickness simultaneously decreases. These results suggest that exchange bias involves some deformation of magnetic order in the interface region.

  8. Automation of FBTR fuel pin inspection using FPGA

    International Nuclear Information System (INIS)

    Khare, K.M.; Pai, Siddhesh; Pant, Brijesh; Sendhil Raja, S.; Gupta, P.K.

    2011-01-01

    A non-contact metrology system for inspection of FBTR fuel pins has been developed. The system consists of a stepper motors driven mechanism for orientation and positioning of FBTR fuel pin, a telecentric imaging system, absolute linear encoder with 0.1 μm resolution and a Field Programmable Gate Array (FPCA) based controller. The FBTR pin assembly is telecentrically illuminated from bottom by a red LED and its shadow graph is imaged using a CCD camera through telecentric imaging lens system. For system control and automation we have used a FPGA that has integrated soft picoblaze processor, X-θ axis motion controller, custom IPs for encoder data acquisition, synchronization circuit, RS485 interface along with other l/Os. Using the Graphical User Interface (GUI) on a PC the system is initialized at home position and the controller provides the trigger signal for start of data acquisition of CCD camera. CCD image of pin and the corresponding X-θ information is captured. After the acquisition of one set of images, the imaging module is moved with a step size pre-programmed to ensure proper stitching of acquired images. The GUI is programmed to analyze these X-θ Images to calculate the required parameters of the fuel pin like the diameter variation, pitch and bow. The details of the instrument and measurements made with it will be presented. (author)

  9. Performance of electrical contact pins near a nuclear explosion

    International Nuclear Information System (INIS)

    Ragan, C.E.; Silbert, M.G.; Ellis, A.N.; Robinson, E.E.; Daddario, M.J.

    1977-09-01

    The pressures attainable in equation-of-state studies using nuclear-explosion-driven shock waves greatly exceed those that can be reached in normal laboratory conditions. However, the diagnostic instrumentation must survive in the high-radiation environment present near such an explosion. Therefore, a set of experiments were fielded on the Redmud event to test the feasibility of using electrical contact pins in this environment. In these experiments a 60-cm-high shield of boron-lead was placed on the rack lid approximately 1 m from the device. A sample consisting of slabs of molybdenum and 238 U was placed on top of the shield, and twelve electrical contact pins were embedded to five different depths in the materials. Five different multiplexing-charging circuits were used for the pins, and a piezoelectric quartz gauge was placed on top of the uranium to obtain an estimate of the fission-energy deposition. All of the charged pins survived the radiation and produced signals indicating shock arrival. The uncertainty in determining the pin-closure time was approximately 3 ns. The signal from the quartz gauge corresponded to a pressure that was consistent with the calculated neutron fluence

  10. Cluster synchronization for directed community networks via pinning partial schemes

    International Nuclear Information System (INIS)

    Hu Cheng; Jiang Haijun

    2012-01-01

    Highlights: ► Cluster synchronization for directed community networks is proposed by pinning partial schemes. ► Each community is considered as a whole. ► Several novel pinning criteria are derived based on the information of communities. ► A numerical example with simulation is provided. - Abstract: In this paper, we focus on driving a class of directed networks to achieve cluster synchronization by pinning schemes. The desired cluster synchronization states are no longer decoupled orbits but a set of un-decoupled trajectories. Each community is considered as a whole and the synchronization criteria are derived based on the information of communities. Several pinning schemes including feedback control and adaptive strategy are proposed to select controlled communities by analyzing the information of each community such as indegrees and outdegrees. In all, this paper answers several challenging problems in pinning control of directed community networks: (1) What communities should be chosen as controlled candidates? (2) How many communities are needed to be controlled? (3) How large should the control gains be used in a given community network to achieve cluster synchronization? Finally, an example with numerical simulations is given to demonstrate the effectiveness of the theoretical results.

  11. Irradiation of TZM: Uranium dioxide fuel pin at 1700 K

    Science.gov (United States)

    Mcdonald, G. E.

    1973-01-01

    A fuel pin clad with TZM and containing solid pellets of uranium dioxide was fission heated in a static helium-cooled capsule at a maximum surface temperature of 1700 K for approximately 1000 hr and to a total burnup of 2.0 percent of the uranium-235. The results of the postirradiation examination indicated: (1) A transverse, intergranular failure of the fuel pin occurred when the fuel pin reached 2.0-percent burnup. This corresponds to 1330 kW-hr/cu cm, where the volume is the sum of the fuel, clad, and void volumes in the fuel region. (2) The maximum swelling of the fuel pin was less than 1.5 percent on the fuel-pin diameter. (3) There was no visible interaction between the TZM clad and the UO2. (4) Irradiation at 1700 K produced a course-grained structure, with an average grain diameter of 0.02 centimeter and with some of the grains extending one-half of the thickness of the clad. (5) Below approximately 1500 K, the irradiation of the clad produced a moderately fine-grained structure, with an average grain diameter of 0.004 centimeter.

  12. Chromium Trioxide Hole-Selective Heterocontacts for Silicon Solar Cells.

    Science.gov (United States)

    Lin, Wenjie; Wu, Weiliang; Liu, Zongtao; Qiu, Kaifu; Cai, Lun; Yao, Zhirong; Ai, Bin; Liang, Zongcun; Shen, Hui

    2018-04-25

    A high recombination rate and high thermal budget for aluminum (Al) back surface field are found in the industrial p-type silicon solar cells. Direct metallization on lightly doped p-type silicon, however, exhibits a large Schottky barrier for the holes on the silicon surface because of Fermi-level pinning effect. As a result, low-temperature-deposited, dopant-free chromium trioxide (CrO x , x solar cell as a hole-selective contact at the rear surface. By using 4 nm CrO x between the p-type silicon and Ag, we achieve a reduction of the contact resistivity for the contact of Ag directly on p-type silicon. For further improvement, we utilize a CrO x (2 nm)/Ag (30 nm)/CrO x (2 nm) multilayer film on the contact between Ag and p-type crystalline silicon (c-Si) to achieve a lower contact resistance (40 mΩ·cm 2 ). The low-resistivity Ohmic contact is attributed to the high work function of the uniform CrO x film and the depinning of the Fermi level of the SiO x layer at the silicon interface. Implementing the advanced hole-selective contacts with CrO x /Ag/CrO x on the p-type silicon solar cell results in a power conversion efficiency of 20.3%, which is 0.1% higher than that of the cell utilizing 4 nm CrO x . Compared with the commercialized p-type solar cell, the novel CrO x -based hole-selective transport material opens up a new possibility for c-Si solar cells using high-efficiency, low-temperature, and dopant-free deposition techniques.

  13. Silicon heterojunction transistor

    International Nuclear Information System (INIS)

    Matsushita, T.; Oh-uchi, N.; Hayashi, H.; Yamoto, H.

    1979-01-01

    SIPOS (Semi-insulating polycrystalline silicon) which is used as a surface passivation layer for highly reliable silicon devices constitutes a good heterojunction for silicon. P- or B-doped SIPOS has been used as the emitter material of a heterojunction transistor with the base and collector of silicon. An npn SIPOS-Si heterojunction transistor showing 50 times the current gain of an npn silicon homojunction transistor has been realized by high-temperature treatments in nitrogen and low-temperature annealing in hydrogen or forming gas

  14. The chemistry of silicon

    CERN Document Server

    Rochow, E G; Emeléus, H J; Nyholm, Ronald

    1975-01-01

    Pergamon Texts in Organic Chemistry, Volume 9: The Chemistry of Silicon presents information essential in understanding the chemical properties of silicon. The book first covers the fundamental aspects of silicon, such as its nuclear, physical, and chemical properties. The text also details the history of silicon, its occurrence and distribution, and applications. Next, the selection enumerates the compounds and complexes of silicon, along with organosilicon compounds. The text will be of great interest to chemists and chemical engineers. Other researchers working on research study involving s

  15. Silicon Microspheres Photonics

    International Nuclear Information System (INIS)

    Serpenguzel, A.

    2008-01-01

    Electrophotonic integrated circuits (EPICs), or alternatively, optoelectronic integrated circuit (OEICs) are the natural evolution of the microelectronic integrated circuit (IC) with the addition of photonic capabilities. Traditionally, the IC industry has been based on group IV silicon, whereas the photonics industry on group III-V semiconductors. However, silicon based photonic microdevices have been making strands in siliconizing photonics. Silicon microspheres with their high quality factor whispering gallery modes (WGMs), are ideal candidates for wavelength division multiplexing (WDM) applications in the standard near-infrared communication bands. In this work, we will discuss the possibility of using silicon microspheres for photonics applications in the near-infrared

  16. Reirradiation of mixed-oxide fuel pins at increased temperatures

    International Nuclear Information System (INIS)

    Lawrence, L.A.; Weber, E.T.

    1976-05-01

    Mixed-oxide fuel pins from EBR-II irradiations were reirradiated in the General Electric Test Reactor (GETR) at higher temperatures than experienced in EBR-II to study effects of the increased operating temperatures on thermal/mechanical and chemical behavior. The response of a mixed-oxide fuel pin to a power increase after having operated at a lower power for a significant portion of its life-time is an area of performance evaluation where little information currently exists. Results show that the cladding diameter changes resulting from the reirradiation are strongly dependent upon both prior burnup level and the magnitude of the temperature increase. Results provide the initial rough outlines of boundaries within which mixed-oxide fuel pins can or cannot tolerate power increases after substantial prior burnup at lower powers

  17. Pin Tool Geometry Effects in Friction Stir Welding

    Science.gov (United States)

    Querin, J. A.; Rubisoff, H. A.; Schneider, J. A.

    2009-01-01

    In friction stir welding (FSW) there is significant evidence that material can take one of two different flow paths when being displaced from its original position in front of the pin tool to its final position in the wake of the weld. The geometry of the pin tool, along with the process parameters, plays an important role in dictating the path that the material takes. Each flow path will impart a different thermomechanical history on the material, consequently altering the material microstructure and subsequent weld properties. The intention of this research is to isolate the effect that different pin tool attributes have on the flow paths imparted on the FSWed material. Based on published weld tool geometries, a variety of weld tools were fabricated and used to join AA2219. Results from the tensile properties and microstructural characterization will be presented.

  18. Control of Flux Pinning in MOD YBCO Coated Conductor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, W. [American Superconductor Corporation, Westborough, MA; Huang, Y. [American Superconductor Corporation, Westborough, MA; Li, X. [American Superconductor Corporation, Westborough, MA; Kodenkandath, Thomas [American Superconductor Corporation, Westborough, MA; Rupich, Marty [American Superconductor Corporation, Westborough, MA; Schoop, U. [American Superconductor Corporation, Westborough, MA; Verebelyi, D. T. [American Superconductor Corporation, Westborough, MA; Thieme, C. L. H. [American Superconductor Corporation, Westborough, MA; Siegal, E. E. [American Superconductor Corporation, Westborough, MA; Holesinger, T. G. [Los Alamos National Laboratory (LANL); Maiorov, B. [Los Alamos National Laboratory (LANL); Miller, D. J. [Argonne National Laboratory (ANL); Maroni, V. A. [Argonne National Laboratory (ANL); Goyal, Amit [ORNL; Specht, Eliot D [ORNL; Paranthaman, Mariappan Parans [ORNL

    2007-01-01

    Two different types of defect structures have been identified to be responsible for the enhanced pinning in metal organic deposited YBCO films. Rare earth additions result in the formation of nanodots in the YBCO matrix, which form uncorrelated pinning centers, increasing pinning in all magnetic field orientations. 124-type intergrowths, which form as laminar structures parallel to the ab-plane, are responsible for the large current enhancement when the magnetic field is oriented in the ab-plane. TEM studies showed that the intergrowths emanate from cuprous containing secondary phase particles, whose density is partially controlled by the rare earth doping level. Critical process parameters have been identified to control this phase formation, and therefore, control the f 24 intergrowth formation. This work has shown that through process control and proper conductor design, either by adjusting the composition or by multiple coatings of different functional layers, the desired angular dependence can be achieved.

  19. Control of flux pinning in MOD YBCO coated conductor.

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, W.; Huang, Y.; Li, X.; Kodenkandath, T.; Rupich, M. W.; Schoop, U.; Verebelyi, D. T.; Thieme, C. L. H.; Siegal, E.; Holesinger, T. G.; Maiorov, B.; Civale, L.; Miller, D. J.; Maroni, V. A.; Li, J.; Martin, P. M.; Specht, E. D.; Goyal, A.; Paranthaman, M. P.; American Superconductor Corp.; LANL; ORNL

    2007-06-01

    NTwo different types of defect structures have been identified to be responsible for the enhanced pinning in metal organic deposited YBCO films. Rare earth additions result in the formation of nanodots in the YBCO matrix, which form uncorrelated pinning centers, increasing pinning in all magnetic field orientations. 124-type intergrowths, which form as laminar structures parallel to the ab-plane, are responsible for the large current enhancement when the magnetic field is oriented in the ab-plane. TEM studies showed that the intergrowths emanate from cuprous containing secondary phase particles, whose density is partially controlled by the rare earth doping level. Critical process parameters have been identified to control this phase formation, and therefore, control the f 24 intergrowth formation. This work has shown that through process control and proper conductor design, either by adjusting the composition or by multiple coatings of different functional layers, the desired angular dependence can be achieved.

  20. Practical synchronization on complex dynamical networks via optimal pinning control

    Science.gov (United States)

    Li, Kezan; Sun, Weigang; Small, Michael; Fu, Xinchu

    2015-07-01

    We consider practical synchronization on complex dynamical networks under linear feedback control designed by optimal control theory. The control goal is to minimize global synchronization error and control strength over a given finite time interval, and synchronization error at terminal time. By utilizing the Pontryagin's minimum principle, and based on a general complex dynamical network, we obtain an optimal system to achieve the control goal. The result is verified by performing some numerical simulations on Star networks, Watts-Strogatz networks, and Barabási-Albert networks. Moreover, by combining optimal control and traditional pinning control, we propose an optimal pinning control strategy which depends on the network's topological structure. Obtained results show that optimal pinning control is very effective for synchronization control in real applications.

  1. Symmetric Pin Diversion Detection using a Partial Defect Detector (PDET)

    International Nuclear Information System (INIS)

    Sitaraman, S.; Ham, Y.S.

    2009-01-01

    Since the signature from the Partial Defect Detector (PDET) is principally dependent on the geometric layout of the guide tube locations, the capability of the technique in detecting symmetric diversion of pins needs to be determined. The Monte Carlo simulation study consisted of cases where pins were removed in a symmetric manner and the resulting signatures were examined. In addition to the normalized gamma-to-neutron ratios, the neutron and gamma signatures normalized to their maximum values, were also examined. Examination of the shape of the three curves as well as of the peak-to-valley differences in excess of the maximum expected in intact assemblies, indicated pin diversion. A set of simulations with various symmetric patterns of diversion were examined. The results from these studies indicated that symmetric diversions as low as twelve percent could be detected by this methodology

  2. Flux pinning in La70 Cu30 disordered system

    International Nuclear Information System (INIS)

    Esquinazi, P.; Guillet, B.; Dussell, H.

    1983-09-01

    Superconducting critical currents were measured as a function of a perpendicular applied magnetic field in disordered La 70 Cu 30 . It is shown that the pinning force is very sensitive to inhomogeneties already present in the as quenched samples, although these inhomogeneties have no obvious influence on other superconducting and transport properties. A simple series resistance model is used to explain the magnetic field dependence of the pinning force. A large decrease of the pinning force was obtained for the annealed samples. This behaviour is consistent with the phase separation model that explains the evolution of the superconductive penetration depth. In order to obtain a better characterization of the structural evolution with annealing of the La 70 Cu 30 system, behaviour of the electrical resistivity, superconducting critical temperature and differential thermal analysis were measured. (author)

  3. Radiation detectors of PIN type for X-rays

    International Nuclear Information System (INIS)

    Ramirez-Jimenez, F.J.

    2003-01-01

    In this laboratory session, tree experiments are proposed: the measurement of X-ray energy spectra from radioactive sources with a high resolution cooled Si-Li detector, with a room temperature PIN diode and the measurement of the response of a PIN diode to the intensity of X-rays of radio-diagnostic units. The spectra obtained with the Si-Li detector help to understand the energy distribution of X-rays and are used as a reference to compare the results obtained with the PIN diode. Measurements in medical X-ray machines are proposed. Low cost, simple electronic instruments and systems are used as tools to make measurements in X-ray units used in radio-diagnostic

  4. Development of wire wrapping technology for FBR fuel pin

    International Nuclear Information System (INIS)

    Nogami, Tetsuya; Seki, Nobuo; Sawayama, Takeo; Ishibashi, Takashi

    1991-01-01

    For the FBR fuel assembly, the spacer wire is adopted to maintain the space between fuel pins. The developments have been carried out to achieve automatically wire wrapping with high precision. Based on the fundamental technology developed through the mock-up test operation, Joyo 'MK-I', fuel pin fabrication was started using partially mechanized wire wrapping machine in 1973. In 1978, an automated wire wrapping machine for Joyo 'MK-II' was developed by the adoption of some improvements for the wire inserting system to end plug hole and the precision of wire pitch. On the bases of these experiences, fully automated wire wrapping machine for 'Monju' fuel pin was installed at Plutonium Fuel Production Facility (PFPF) in 1987. (author)

  5. Component Pin Recognition Using Algorithms Based on Machine Learning

    Science.gov (United States)

    Xiao, Yang; Hu, Hong; Liu, Ze; Xu, Jiangchang

    2018-04-01

    The purpose of machine vision for a plug-in machine is to improve the machine’s stability and accuracy, and recognition of the component pin is an important part of the vision. This paper focuses on component pin recognition using three different techniques. The first technique involves traditional image processing using the core algorithm for binary large object (BLOB) analysis. The second technique uses the histogram of oriented gradients (HOG), to experimentally compare the effect of the support vector machine (SVM) and the adaptive boosting machine (AdaBoost) learning meta-algorithm classifiers. The third technique is the use of an in-depth learning method known as convolution neural network (CNN), which involves identifying the pin by comparing a sample to its training. The main purpose of the research presented in this paper is to increase the knowledge of learning methods used in the plug-in machine industry in order to achieve better results.

  6. FFTF/IEM cell fuel pin weighing system

    International Nuclear Information System (INIS)

    Gibbons, P.W.

    1987-01-01

    The Interim Examination and Maintenance (IEM) cell in the Fast Flux Test Facility (FFTF) is used for remote disassembly of irradiated fuel and materials experiments. For those fuel experiments where the FFTF tag-gas detection system has indicated a fuel pin cladding breach, a weighing system is used in identifying that fuel pin with a reduced weight due to the escape of gaseous and volatile fission products. A fuel pin weighing machine, originally purchased for use in the Fuels and Materials Examination Facility (FMEF), was the basis for the IEM cell system. Design modifications to the original equipment were centered around adapting the machine to the differences between the two facilities and correcting deficiencies discovered during functional testing in the IEM cell mock-up

  7. Testbeam evaluation of silicon strip modules for ATLAS Phase - II Strip Tracker Upgrade

    CERN Document Server

    Blue, Andrew; The ATLAS collaboration; Ai, Xiaocong; Allport, Phillip; Arling, Jan-Hendrik; Atkin, Ryan Justin; Bruni, Lucrezia Stella; Carli, Ina; Casse, Gianluigi; Chen, Liejian; Chisholm, Andrew; Cormier, Kyle James Read; Cunningham, William Reilly; Dervan, Paul; Diez Cornell, Sergio; Dolezal, Zdenek; Dopke, Jens; Dreyer, Etienne; Dreyling-Eschweiler, Jan Linus Roderik; Escobar, Carlos; Fabiani, Veronica; Fadeyev, Vitaliy; Fernandez Tejero, Javier; Fleta Corral, Maria Celeste; Gallop, Bruce; Garcia-Argos, Carlos; Greenall, Ashley; Gregor, Ingrid-Maria; Greig, Graham George; Guescini, Francesco; Hara, Kazuhiko; Hauser, Marc Manuel; Huang, Yanping; Hunter, Robert Francis Holub; Keller, John; Klein, Christoph; Kodys, Peter; Koffas, Thomas; Kotek, Zdenek; Kroll, Jiri; Kuehn, Susanne; Lee, Steven Juhyung; Liu, Yi; Lohwasser, Kristin; Meszarosova, Lucia; Mikestikova, Marcela; Mi\\~nano Moya, Mercedes; Mori, Riccardo; Moser, Brian; Nikolopoulos, Konstantinos; Peschke, Richard; Pezzullo, Giuseppe; Phillips, Peter William; Poley, Anne-luise; Queitsch-Maitland, Michaela; Ravotti, Federico; Rodriguez Rodriguez, Daniel

    2018-01-01

    The planned HL-LHC (High Luminosity LHC) is being designed to maximise the physics potential of the LHC with 10 years of operation at instantaneous luminosities of \\mbox{$7.5\\times10^{34}\\;\\mathrm{cm}^{-2}\\mathrm{s}^{-1}$}. A consequence of this increased luminosity is the expected radiation damage requiring the tracking detectors to withstand hadron equivalences to over $1x10^{15}$ 1 MeV neutron equivalent per $cm^{2}$ in the ATLAS Strips system. The silicon strip tracker exploits the concept of modularity. Fast readout electronics, deploying 130nm CMOS front-end electronics are glued on top of a silicon sensor to make a module. The radiation hard n-in-p micro-strip sensors used have been developed by the ATLAS ITk Strip Sensor collaboration and produced by Hamamatsu Photonics. A series of tests were performed at the DESY-II test beam facility to investigate the detailed performance of a strip module with both 2.5cm and 5cm length strips before irradiation. The DURANTA telescope was used to obtain a pointing...

  8. Impact of low-dose electron irradiation on n+p silicon strip sensors

    CERN Document Server

    Adam, W.; Dragicevic, M.; Friedl, M.; Fruehwirth, R.; Hoch, M.; Hrubec, J.; Krammer, M.; Treberspurg, W.; Waltenberger, W.; Alderweireldt, S.; Beaumont, W.; Janssen, X.; Luyckx, S.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Barria, P.; Caillol, C.; Clerbaux, B.; De Lentdecker, G.; Dobur, D.; Favart, L.; Grebenyuk, A.; Lenzi, Th.; Leonard, A.; Maerschalk, Th.; Mohammadi, A.; Pernie, L.; Randle-Conde, A.; Reis, T.; Seva, T.; Thomas, L.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Zenoni, F.; Abu Zeid, S.; Blekman, F.; De Bruyn, I.; D'Hondt, J.; Daci, N.; Deroover, K.; Heracleous, N.; Keaveney, J.; Lowette, S.; Moreels, L.; Olbrechts, A.; Python, Q.; Tavernier, S.; Van Mulders, P.; Van Onsem, G.; Van Parijs, I.; Strom, D.A.; Basegmez, S.; Bruno, G.; Castello, R.; Caudron, A.; Ceard, L.; De Callatay, B.; Delaere, C.; Pree, T.Du; Forthomme, L.; Giammanco, A.; Hollar, J.; Jez, P.; Michotte, D.; Nuttens, C.; Perrini, L.; Pagano, D.; Quertenmont, L.; Selvaggi, M.; Marono, M.Vidal; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G.H.; Harkonen, J.; Lampen, T.; Luukka, P.R.; Maenpaa, T.; Peltola, T.; Tuominen, E.; Tuovinen, E.; Eerola, P.; Tuuva, T.; Beaulieu, G.; Boudoul, G.; Combaret, C.; Contardo, D.; Gallbit, G.; Lumb, N.; Mathez, H.; Mirabito, L.; Perries, S.; Sabes, D.; Vander Donckt, M.; Verdier, P.; Viret, S.; Zoccarato, Y.; Agram, J.L.; Conte, E.; Fontaine, J.Ch.; Andrea, J.; Bloch, D.; Bonnin, C.; Brom, J.M.; Chabert, E.; Charles, L.; Goetzmann, Ch.; Gross, L.; Hosselet, J.; Mathieu, C.; Richer, M.; Skovpen, K.; Autermann, C.; Edelhoff, M.; Esser, H.; Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Ostapchuk, A.; Pierschel, G.; Preuten, M.; Raupach, F.; Sammet, J.; Schael, S.; Schwering, G.; Wittmer, B.; Wlochal, M.; Zhukov, V.; Pistone, C.; Fluegge, G.; Kuensken, A.; Geisler, M.; Pooth, O.; Stahl, A.; Bartosik, N.; Behr, J.; Burgmeier, A.; Calligaris, L.; Dolinska, G.; Eckerlin, G.; Eckstein, D.; Eichhorn, T.; Fluke, G.; Garcia, J.Garay; Gizhko, A.; Hansen, K.; Harb, A.; Hauk, J.; Kalogeropoulos, A.; Kleinwort, C.; Korol, I.; Lange, W.; Lohmann, W.; Mankel, R.; Maser, H.; Mittag, G.; Muhl, C.; Mussgiller, A.; Nayak, A.; Ntomari, E.; Perrey, H.; Pitzl, D.; Schroeder, M.; Seitz, C.; Spannagel, S.; Zuber, A.; Biskop, H.; Blobel, V.; Buhmann, P.; Centis-Vignali, M.; Draeger, A.R.; Erfle, J.; Garutti, E.; Haller, J.; Henkel, Ch.; Hoffmann, M.; Junkes, A.; Klanner, R.; Lapsien, T.; Mattig, S.; Matysek, M.; Perieanu, A.; Poehlsen, J.; Poehlsen, T.; Scharf, Ch.; Schleper, P.; Schmidt, A.; Schuwalow, S.; Schwandt, J.; Sola, V.; Steinbruck, G.; Vormwald, B.; Wellhausen, J.; Barvich, T.; Barth, Ch.; Boegelspacher, F.; De Boer, W.; Butz, E.; Casele, M.; Colombo, F.; Dierlamm, A.; Eber, R.; Freund, B.; Hartmann, F.; Hauth, Th.; Heindl, S.; Hoffmann, K.H.; Husemann, U.; Kornmeyer, A.; Mallows, S.; Muller, Th.; Nuernberg, A.; Printz, M.; Simonis, H.J.; Steck, P.; Weber, M.; Weiler, Th.; Bhardwaj, A.; Kumar, A.; Ranjan, K.; Bakhshiansohl, H.; Behnamian, H.; Khakzad, M.; Naseri, M.; Cariola, P.; De Robertis, G.; Fiore, L.; Franco, M.; Loddo, F.; Sala, G.; Silvestris, L.; Creanza, D.; De Palma, M.; Maggi, G.; My, S.; Selvaggi, G.; Albergo, S.; Cappello, G.; Chiorboli, M.; Costa, S.; Giordano, F.; Di Mattia, A.; Potenza, R.; Saizu, M.A.; Tricomi, A.; Tuve, C.; Barbagli, G.; Brianzi, M.; Ciaranfi, R.; Civinini, C.; Gallo, E.; Meschini, M.; Paoletti, S.; Sguazzoni, G.; Ciulli, V.; D'Alessandro, R.; Gonzi, S.; Gori, V.; Focardi, E.; Lenzi, P.; Scarlini, E.; Tropiano, A.; Viliani, L.; Ferro, F.; Robutti, E.; Lo Vetere, M.; Gennai, S.; Malvezzi, S.; Menasce, D.; Moroni, L.; Pedrini, D.; Dinardo, M.; Fiorendi, S.; Manzoni, R.A.; Azzi, P.; Bacchetta, N.; Bisello, D.; Dall'Osso, M.; Dorigo, T.; Giubilato, P.; Pozzobon, N.; Tosi, M.; Zucchetta, A.; De Canio, F.; Gaioni, L.; Manghisoni, M.; Nodari, B.; Re, V.; Traversi, G.; Comotti, D.; Ratti, L.; Bilei, G.M.; Bissi, L.; Checcucci, B.; Magalotti, D.; Menichelli, M.; Saha, A.; Servoli, L.; Storchi, L.; Biasini, M.; Conti, E.; Ciangottini, D.; Fano, L.; Lariccia, P.; Mantovani, G.; Passeri, D.; Placidi, P.; Salvatore, M.; Santocchia, A.; Solestizi, L.A.; Spiezia, A.; Demaria, N.; Rivetti, A.; Bellan, R.; Casasso, S.; Costa, M.; Covarelli, R.; Migliore, E.; Monteil, E.; Musich, M.; Pacher, L.; Ravera, F.; Romero, A.; Solano, A.; Trapani, P.; Jaramillo Echeverria, R.; Fernandez, M.; Gomez, G.; Moya, D.; F. Gonzalez Sanchez, J.; Munoz Sanchez, F.J.; Vila, I.; Virto, A.L.; Abbaneo, D.; Ahmed, I.; Albert, E.; Auzinger, G.; Berruti, G.; Bianchi, G.; Blanchot, G.; Breuker, H.; Ceresa, D.; Christiansen, J.; Cichy, K.; Daguin, J.; D'Alfonso, M.; D'Auria, A.; Detraz, S.; De Visscher, S.; Deyrail, D.; Faccio, F.; Felici, D.; Frank, N.; Gill, K.; Giordano, D.; Harris, P.; Honma, A.; Kaplon, J.; Kornmayer, A.; Kortelainen, M.; Kottelat, L.; Kovacs, M.; Mannelli, M.; Marchioro, A.; Marconi, S.; Martina, S.; Mersi, S.; Michelis, S.; Moll, M.; Onnela, A.; Pakulski, T.; Pavis, S.; Peisert, A.; Pernot, J.F.; Petagna, P.; Petrucciani, G.; Postema, H.; Rose, P.; Rzonca, M.; Stoye, M.; Tropea, P.; Troska, J.; Tsirou, A.; Vasey, F.; Vichoudis, P.; Verlaat, B.; Zwalinski, L.; Bachmair, F.; Becker, R.; Bani, L.; di Calafiori, D.; Casal, B.; Djambazov, L.; Donega, M.; Dunser, M.; Eller, P.; Grab, C.; Hits, D.; Horisberger, U.; Hoss, J.; Kasieczka, G.; Lustermann, W.; Mangano, B.; Marionneau, M.; Martinez Ruiz del Arbol, P.; Masciovecchio, M.; Perrozzi, L.; Roeser, U.; Rossini, M.; Starodumov, A.; Takahashi, M.; Wallny, R.; Amsler, C.; Bosiger, K.; Caminada, L.; Canelli, F.; Chiochia, V.; De Cosa, A.; Galloni, C.; Hreus, T.; Kilminster, B.; Lange, C.; Maier, R.; Ngadiuba, J.; Pinna, D.; Robmann, P.; Taroni, S.; Yang, Y.; Bertl, W.; Deiters, K.; Erdmann, W.; Horisberger, R.; Kaestli, H.C.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Streuli, S.; Chen, P.H.; Dietz, C.; Grundler, U.; Hou, W.S.; Lu, R.S.; Moya, M.; Wilken, R.; Cussans, D.; Flacher, H.; Goldstein, J.; Grimes, M.; Jacob, J.; El Nasr-Storey, S.Seif; Cole, J.; Hobson, P.; Leggat, D.; Reid, I.D.; Teodorescu, L.; Bainbridge, R.; Dauncey, P.; Fulcher, J.; Hall, G.; Magnan, A.M.; Pesaresi, M.; Raymond, D.M.; Uchida, K.; Coughlan, J.A.; Harder, K.; Ilic, J.; Tomalin, I.R.; Garabedian, A.; Heintz, U.; Narain, M.; Nelson, J.; Sagir, S.; Speer, T.; Swanson, J.; Tersegno, D.; Watson-Daniels, J.; Chertok, M.; Conway, J.; Conway, R.; Flores, C.; Lander, R.; Pellett, D.; Ricci-Tam, F.; Squires, M.; Thomson, J.; Yohay, R.; Burt, K.; Ellison, J.; Hanson, G.; Malberti, M.; Olmedo, M.; Cerati, G.; Sharma, V.; Vartak, A.; Yagil, A.; Della Porta, G.Zevi; Dutta, V.; Gouskos, L.; Incandela, J.; Kyre, S.; McColl, N.; Mullin, S.; White, D.; Cumalat, J.P.; Ford, W.T.; Gaz, A.; Krohn, M.; Stenson, K.; Wagner, S.R.; Baldin, B.; Bolla, G.; Burkett, K.; Butler, J.; Cheung, H.; Chramowicz, J.; Christian, D.; Cooper, W.E.; Deptuch, G.; Derylo, G.; Gingu, C.; Gruenendahl, S.; Hasegawa, S.; Hoff, J.; Howell, J.; Hrycyk, M.; Jindariani, S.; Johnson, M.; Jung, A.; Joshi, U.; Kahlid, F.; Lei, C.M.; Lipton, R.; Liu, T.; Los, S.; Matulik, M.; Merkel, P.; Nahn, S.; Prosser, A.; Rivera, R.; Shenai, A.; Spiegel, L.; Tran, N.; Uplegger, L.; Voirin, E.; Yin, H.; Adams, M.R.; Berry, D.R.; Evdokimov, A.; Evdokimov, O.; Gerber, C.E.; Hofman, D.J.; Kapustka, B.K.; O'Brien, C.; Sandoval Gonzalez, D.I.; Trauger, H.; Turner, P.; Parashar, N.; Stupak, J., III; Bortoletto, D.; Bubna, M.; Hinton, N.; Jones, M.; Miller, D.H.; Shi, X.; Tan, P.; Baringer, P.; Bean, A.; Benelli, G.; Gray, J.; Majumder, D.; Noonan, D.; Sanders, S.; Stringer, R.; Ivanov, A.; Makouski, M.; Skhirtladze, N.; Taylor, R.; Anderson, I.; Fehling, D.; Gritsan, A.; Maksimovic, P.; Martin, C.; Nash, K.; Osherson, M.; Swartz, M.; Xiao, M.; Acosta, J.G.; Cremaldi, L.M.; Oliveros, S.; Perera, L.; Summers, D.; Bloom, K.; Bose, S.; Claes, D.R.; Dominguez, A.; Fangmeier, C.; Gonzalez Suarez, R.; Meier, F.; Monroy, J.; Hahn, K.; Sevova, S.; Sung, K.; Trovato, M.; Bartz, E.; Duggan, D.; Halkiadakis, E.; Lath, A.; Park, M.; Schnetzer, S.; Stone, R.; Walker, M.; Malik, S.; Mendez, H.; Ramirez Vargas, J.E.; Alyari, M.; Dolen, J.; George, J.; Godshalk, A.; Iashvili, I.; Kaisen, J.; Kharchilava, A.; Kumar, A.; Rappoccio, S.; Alexander, J.; Chaves, J.; Chu, J.; Dittmer, S.; Kaufman, G.; Mirman, N.; Ryd, A.; Salvati, E.; Skinnari, L.; Thom, J.; Thompson, J.; Tucker, J.; Winstrom, L.; Akgun, B.; Ecklund, K.M.; Nussbaum, T.; Zabel, J.; Betchart, B.; Demina, R.; Hindrichs, O.; Petrillo, G.; Eusebi, R.; Osipenkov, I.; Perloff, A.; Ulmer, K.A.; Delannoy, A.G.; D'Angelo, P.; Johns, W.

    2015-01-01

    The response of n+p silicon strip sensors to electrons from a Sr-90 source was measured using a multi-channel read-out system with 25 ns sampling time. The measurements were performed over a period of several weeks, during which the operating conditions were varied. The sensors were fabricated by Hamamatsu Photonics K.K. on 200 micrometer thick float-zone and magnetic-Czochralski silicon. Their pitch was 80 micrometer, and both p-stop and p-spray isolation of the n+ strips were studied. The electrons from the Sr-90 source were collimated to a spot with a full-width-at-half-maximum of 2 mm at the sensor surface, and the dose rate in the SiO2 at the maximum was about 50 Gy/d. After only a few hours of making measurements, significant changes in charge collection and charge sharing were observed. Annealing studies, with temperatures up to 80{\\deg}C and annealing times of 18 hours, showed that the changes can only be partially annealed. The observations can be qualitatively explained by the increase of the positi...

  9. Characterization of silicon sensor materials and designs for the CMS Tracker Upgrade

    CERN Document Server

    Dierlamm, Alexander Hermann

    2012-01-01

    During the high luminosity phase of the LHC (HL-LHC, starting around 2020) the inner tracking system of CMS will be exposed to harsher conditions than the current system was designed for. Therefore a new tracker is planned to cope with higher radiation levels and higher occupancies. Within the strip sensor developments of CMS a comparative survey of silicon materials and technologies is being performed in order to identify the baseline material for the future tracker. Hence, a variety of materials (float-zone, magnetic Czochralski and epitaxially grown silicon with thicknesses from 50$\\mu$m to 320$\\mu$m as p- and n-type) has been processed at one company (Hamamatsu Photonics K.K.), irradiated (proton, neutron and mixed irradiations up to 1.5e15n$_{eq}$/cm$^2$ and beyond) and tested under identical conditions. The wafer layout includes a variety of devices to investigate different aspects of sensor properties like simple diodes, test-structures, small strip sensors and a strip sensor array with varying strip p...

  10. Design and tests of the silicon sensors for the ZEUS micro vertex detector

    International Nuclear Information System (INIS)

    Dannheim, D.; Koetz, U.; Coldewey, C.; Fretwurst, E.; Garfagnini, A.; Klanner, R.; Martens, J.; Koffeman, E.; Tiecke, H.; Carlin, R.

    2003-01-01

    To fully exploit the HERA-II upgrade, the ZEUS experiment has installed a Micro Vertex Detector (MVD) using n-type, single-sided, silicon μ-strip sensors with capacitive charge division. The sensors have a readout pitch of 120 μm, with five intermediate strips (20 μm strip pitch). The designs of the silicon sensors and of the test structures used to verify the technological parameters, are presented. Results on the electrical measurements are discussed. A total of 1123 sensors with three different geometries have been produced by Hamamatsu Photonics K.K. Irradiation tests with reactor neutrons and 60 Co photons have been performed for a small sample of sensors. The results on neutron irradiation (with a fluence of 1x10 13 1 MeV equivalent neutrons/cm 2 ) are well described by empirical formulae for bulk damage. The 60 Co photons (with doses up to 2.9 kGy) show the presence of generation currents in the SiO 2 -Si interface, a large shift of the flatband voltage and a decrease of the hole mobility

  11. Performance test of Si PIN photodiode line scanner for thermal neutron detection

    Energy Technology Data Exchange (ETDEWEB)

    Totsuka, Daisuke, E-mail: totsuka@imr.tohoku.ac.jp [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Nihon Kessho Kogaku Co., Ltd., 810-5 Nobe-cho Tatebayashi, Gunma 374-0047 (Japan); Yanagida, Takayuki [New Industry Creation Hatchery Center (NICHe) 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Fukuda, Kentaro; Kawaguchi, Noriaki [Tokuyama Corp., 3 Shibuya Shibuya-ku, Tokyo 150-8383 (Japan); Fujimoto, Yutaka [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Pejchal, Jan [Institute of Physics AS CR, Cukrovarnicka 10, Prague 6, 162-53 (Czech Republic); Yokota, Yuui [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Yoshikawa, Akira [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); New Industry Creation Hatchery Center (NICHe) 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan)

    2011-12-11

    Thermal neutron imaging using Si PIN photodiode line scanner and Eu-doped LiCaAlF{sub 6} crystal scintillator has been developed. The pixel dimensions of photodiode are 1.18 mm (width) Multiplication-Sign 3.8 mm (length) with 0.4 mm gap and the module has 192 channels in linear array. The emission peaks of Eu-doped LiCaAlF{sub 6} after thermal neutron excitation are placed at 370 and 590 nm, and the corresponding photon sensitivities of photodiode are 0.04 and 0.34 A/W, respectively. Polished scintillator blocks with a size of 1.18 mm (width) Multiplication-Sign 3.8 mm (length) Multiplication-Sign 5.0 mm (thickness) were wrapped by several layers of Teflon tapes as a reflector and optically coupled to the photodiodes by silicone grease. JRR-3 MUSASI beam line emitting 13.5 meV thermal neutrons with the flux of 8 Multiplication-Sign 10{sup 5} n/cm{sup 2} s was used for the imaging test. As a subject for imaging, a Cd plate was moved at the speed of 50 mm/s perpendicular to the thermal neutron beam. Analog integration time was set to be 416.6 {mu}s, then signals were converted by a delta-sigma A/D converter. After the image processing, we successfully obtained moving Cd plate image under thermal neutron irradiation using PIN photodiode line scanner coupled with Eu-doped LiCaAlF{sub 6} scintillator.

  12. Performance test of Si PIN photodiode line scanner for thermal neutron detection

    International Nuclear Information System (INIS)

    Totsuka, Daisuke; Yanagida, Takayuki; Fukuda, Kentaro; Kawaguchi, Noriaki; Fujimoto, Yutaka; Pejchal, Jan; Yokota, Yuui; Yoshikawa, Akira

    2011-01-01

    Thermal neutron imaging using Si PIN photodiode line scanner and Eu-doped LiCaAlF 6 crystal scintillator has been developed. The pixel dimensions of photodiode are 1.18 mm (width)×3.8 mm (length) with 0.4 mm gap and the module has 192 channels in linear array. The emission peaks of Eu-doped LiCaAlF 6 after thermal neutron excitation are placed at 370 and 590 nm, and the corresponding photon sensitivities of photodiode are 0.04 and 0.34 A/W, respectively. Polished scintillator blocks with a size of 1.18 mm (width)×3.8 mm (length)×5.0 mm (thickness) were wrapped by several layers of Teflon tapes as a reflector and optically coupled to the photodiodes by silicone grease. JRR-3 MUSASI beam line emitting 13.5 meV thermal neutrons with the flux of 8×10 5 n/cm 2 s was used for the imaging test. As a subject for imaging, a Cd plate was moved at the speed of 50 mm/s perpendicular to the thermal neutron beam. Analog integration time was set to be 416.6 μs, then signals were converted by a delta-sigma A/D converter. After the image processing, we successfully obtained moving Cd plate image under thermal neutron irradiation using PIN photodiode line scanner coupled with Eu-doped LiCaAlF 6 scintillator.

  13. Fabrication of Fast Reactor Fuel Pins for Test Irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Karsten, G. [Institute for Applied Reactor Physics, Kernforschungszentrum Karlsruhe, Karlsruhe, Federal Republic of Germany (Germany); Dippel, T. [Institute for Radiochemistry, Kernforschungszentrum Karlsruhe, Karlsruhe, Federal Republic of Germany (Germany); Laue, H. J. [Institute for Applied Reactor Physics, Kernforschungszentrum Karlsruhe, Karlsruhe, Federal Republic of Germany (Germany)

    1967-09-15

    An extended irradiation programme is being carried out for the fuel element development of the Karlsruhe fast breeder project. A very important task within the programme is the testing of plutonium-containing fuel pins in a fast-reactor environment. This paper deals with fabrication of such pins by our laboratories at Karlsruhe. For the fast reactor test positions at present envisaged a fuel with 15% plutonium and the uranium fully enriched is appropriate. Hie mixed oxide is both pelletized and vibro-compacted with smeared densities between 80 and 88% theoretical. The pin design is, for example, such that there are two gas plena at the top and bottom, and one blanket above the fuel with the fuel zone fitting to the test reactor core length. The specifications both for fuel and cladding have been adapted to the special purpose of a fast-breeder reactor - the outer dimensions, the choice of cladding and fuel types, the data used and the kind of tests outline the targets of the development. The fuel fabrication is described in detail, and also the powder line used for vibro-compaction. The source materials for the fuel are oxalate PuO{sub 2} and UO{sub 2} from the UF{sub 6} process. The special problems of mechanical mixing and of plutonium homogeneity have been studied. The development of the sintering technique and grain characteristics for vibratory compactive fuel had to overcome serious problems in order to reach 82-83% theoretical. The performance of the pin fabrication needed a major effort in welding, manufacturing of fits and decontamination of the pin surfaces. This was a stimulation for the development of some very subtle control techniques, for example taking clear X-ray photographs and the tube testing. In general the selection of tests was a special task of the production routine. In conclusion the fabrication of the pins resulted in valuable experiences for the further development of fast reactor fuel elements. (author)

  14. Velocity distribution measurement in wire-spaced fuel pin bundle

    International Nuclear Information System (INIS)

    Mizuta, Hiroshi; Ohtake, Toshihide; Uruwashi, Shinichi; Takahashi, Keiichi

    1974-01-01

    Flow distribution measurement was made in the subchannels of a pin bundle in air flow. The present paper is interim because the target of this work is the decision of temperature of the pin surface in contact with wire spacers. The wire-spaced fuel pin bundle used for the experiment consists of 37 simulated fuel pins of stainless steel tubes, 3000 mm in length and 31.6 mm in diameter, which are wound spirally with 6 mm stainless steel wire. The bundle is wrapped with a hexagonal tube, 3500 mm in length and 293 mm in flat-to-flat distance. The bundle is fixed with knock-bar at the entrance of air flow in the hexagonal tube. The pitch of pins in the bundle is 37.6 mm (P/D=1.19) and the wrapping pitch of wire is 1100 mm (H/D=34.8). A pair of arrow-type 5-hole Pitot tubes are used to measure the flow velocity and the direction of air flow in the pin bundle. The measurement of flow distribution was made with the conditions of air flow rate of 0.33 m 3 /sec, air temperature of 45 0 C, and average Reynolds number of 15100 (average air velocity of 20.6 m/sec.). It was found that circular flow existed in the down stream of wire spacers, that axial flow velocity was slower in the subchannels, which contained wire spacers, than in those not affected by the wire, and that the flow angle to the axial velocity at the boundary of subchannels was two thirds smaller than wire wrapping angle. (Tai, I.)

  15. Pin-photodiode array for the measurement of fan-beam energy and air kerma distributions of X-ray CT scanners.

    Science.gov (United States)

    Haba, Tomonobu; Koyama, Shuji; Aoyama, Takahiko; Kinomura, Yutaka; Ida, Yoshihiro; Kobayashi, Masanao; Kameyama, Hiroshi; Tsutsumi, Yoshinori

    2016-07-01

    Patient dose estimation in X-ray computed tomography (CT) is generally performed by Monte Carlo simulation of photon interactions within anthropomorphic or cylindrical phantoms. An accurate Monte Carlo simulation requires an understanding of the effects of the bow-tie filter equipped in a CT scanner, i.e. the change of X-ray energy and air kerma along the fan-beam arc of the CT scanner. To measure the effective energy and air kerma distributions, we devised a pin-photodiode array utilizing eight channels of X-ray sensors arranged at regular intervals along the fan-beam arc of the CT scanner. Each X-ray sensor consisted of two plate type of pin silicon photodiodes in tandem - front and rear photodiodes - and of a lead collimator, which only allowed X-rays to impinge vertically to the silicon surface of the photodiodes. The effective energy of the X-rays was calculated from the ratio of the output voltages of the photodiodes and the dose was calculated from the output voltage of the front photodiode using the energy and dose calibration curves respectively. The pin-photodiode array allowed the calculation of X-ray effective energies and relative doses, at eight points simultaneously along the fan-beam arc of a CT scanner during a single rotation of the scanner. The fan-beam energy and air kerma distributions of CT scanners can be effectively measured using this pin-photodiode array. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  16. Amorphous silicon pixel radiation detectors and associated thin film transistor electronics readout

    International Nuclear Information System (INIS)

    Perez-Mendez, V.; Drewery, J.; Hong, W.S.; Jing, T.; Kaplan, S.N.; Lee, H.; Mireshghi, A.

    1994-10-01

    We describe the characteristics of thin (1 μm) and thick (>30 μm) hydrogenated amorphous silicon p-i-n diodes which are optimized for detecting and recording the spatial distribution of charged particles, x-rays and γ rays. For x-ray, γ ray, and charged particle detection we can use thin p-i-n photosensitive diode arrays coupled to evaporated layers of suitable scintillators. For direct detection of charged particles with high resistance to radiation damage, we use the thick p-i-n diode arrays. Deposition techniques using helium dilution, which produce samples with low stress are described. Pixel arrays for flux exposures can be readout by transistor, single diode or two diode switches. Polysilicon charge sensitive pixel amplifiers for single event detection are described. Various applications in nuclear, particle physics, x-ray medical imaging, neutron crystallography, and radionuclide chromatography are discussed

  17. Measurements of the reverse current of highly irradiated silicon sensors to determine the effective energy and current related damage rate

    Science.gov (United States)

    Wiehe, Moritz; Wonsak, S.; Kuehn, S.; Parzefall, U.; Casse, G.

    2018-01-01

    The reverse current of irradiated silicon sensors leads to self heating of the sensor and degrades the signal to noise ratio of a detector. Precise knowledge of the expected reverse current during detector operation is crucial for planning and running experiments in High Energy Physics. The dependence of the reverse current on sensor temperature and irradiation fluence is parametrized by the effective energy and the current related damage rate, respectively. In this study 18 n-in-p mini silicon strip sensors from companies Hamamatsu Photonics and Micron Semiconductor Ltd. were deployed. Measurements of the reverse current for different bias voltages were performed at temperatures of -32 ° C, -27 ° C and -23 ° C. The sensors were irradiated with reactor neutrons in Ljubljana to fluences ranging from 2 × 1014neq /cm2 to 2 × 1016neq /cm2. The measurements were performed directly after irradiation and after 10 and 30 days of room temperature annealing. The aim of the study presented in this paper is to investigate the reverse current of silicon sensors for high fluences of up to 2 × 1016neq /cm2 and compare the measurements to the parametrization models.

  18. Method and apparatus for enhancing vortex pinning by conformal crystal arrays

    Science.gov (United States)

    Janko, Boldizsar; Reichhardt, Cynthia; Reichhardt, Charles; Ray, Dipanjan

    2015-07-14

    Disclosed is a method and apparatus for strongly enhancing vortex pinning by conformal crystal arrays. The conformal crystal array is constructed by a conformal transformation of a hexagonal lattice, producing a non-uniform structure with a gradient where the local six-fold coordination of the pinning sites is preserved, and with an arching effect. The conformal pinning arrays produce significantly enhanced vortex pinning over a much wider range of field than that found for other vortex pinning geometries with an equivalent number of vortex pinning sites, such as random, square, and triangular.

  19. Pinning synchronization of delayed complex dynamical networks with nonlinear coupling

    Science.gov (United States)

    Cheng, Ranran; Peng, Mingshu; Yu, Weibin

    2014-11-01

    In this paper, we find that complex networks with the Watts-Strogatz or scale-free BA random topological architecture can be synchronized more easily by pin-controlling fewer nodes than regular systems. Theoretical analysis is included by means of Lyapunov functions and linear matrix inequalities (LMI) to make all nodes reach complete synchronization. Numerical examples are also provided to illustrate the importance of our theoretical analysis, which implies that there exists a gap between the theoretical prediction and numerical results about the minimum number of pinning controlled nodes.

  20. Creep relaxation of fuel pin bending and ovalling stresses

    International Nuclear Information System (INIS)

    Chan, D.P.; Jackson, R.J.

    1979-06-01

    Analytical methods for calculating fuel pin cladding bending and ovalling stresses due to pin bundle-duct mechanical interaction taking into account nonlinear creep are presented. Calculated results are in close agreement with finite element results by MARC-CDC program. The methods are used to investigate the effect of creep on the FTR fuel cladding bending and ovalling stresses. It is concluded that the cladding of 316 SS 20% CW and reference design has high creep rates in the FTR core region to keep the bending and ovalling stresses to low levels

  1. Nuclear fuel assemblies and fuel pins usable in such assemblies

    International Nuclear Information System (INIS)

    Jolly, R.

    1982-01-01

    A novel end cap for a nuclear fuel assembly is described in detail. It consists of a trisection arrangement which is received within a cell of a cellular grid. The cell contains abutment means with which the trisection comes into abutment. The grid also contains an abutment means for preventing the trisections from being inserted into the cell in an incorrect orientation. The present design allows fuel pins to be securely held in a hold-down grid of a sub-assembly. The design also allows easier dis-assembly of the swollen and embrittled fuel pins prior to reprocessing. (U.K.)

  2. 8 Pin RIC Socket for Hearing Aid Applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Davids, Søren

    2012-01-01

    process and the other one is fully automated process. This paper presents the entire process chain for both the concepts and makes a comparative analysis based on the experimental investigation and validation. The work presented here can be a source of valuable information for industrial users...... of them. 8 Pin RIC Socket is a functionally versatile product which can combine many different functions and presents many advantages compared with the previous 3 Pin RIC Socket. For the demonstrator production of the new Socket, two different production concepts were chosen- one based on semi-automated...

  3. Fuel pin failure in the PFR/TREAT experiments

    International Nuclear Information System (INIS)

    Herbert, R.; Hunter, C.W.; Kramer, J.M.; Wood, M.H.; Wright, A.E.

    1986-01-01

    The PFR/TREAT safety testing programme involves the transient testing of fresh and pre-irradiated UK and US fuel pins. This paper summarizes the experimental and calculational results obtained to date on fuel pin failure during transient overpower (resulting from an accidental addition of resolivity) and transient undercooling followed by overpower (arising from an accidental stoppage of the primary sodium circulating pumps) accidents. Companion papers at this conference address: (I) the progress and future plans of the programme, and (II) post-failure material movements

  4. Influence of LMFBR fuel pin temperature profiles on corrosion rate

    International Nuclear Information System (INIS)

    Shiels, S.A.; Bagnall, C.; Schrock, S.L.; Orbon, S.J.

    1976-01-01

    The paper describes the sodium corrosion behavior of 20 percent cold worked Type 316 stainless steel fuel pin cladding under a simulated reactor thermal environment. A temperature gradient, typical of a fuel pin, was generated in a 0.9 m long heater section by direct resistance heating. Specimens were located in an isothermal test section immediately downstream of the heater. A comparison of the measured corrosion rates with available data showed an enhancement factor of between 1.5 and 2 which was attributed to the severe axial temperature gradient through the heater. Differences in structure and surface chemistry were also noted

  5. Establishment of the PIN within the Colombian party system

    Directory of Open Access Journals (Sweden)

    Vanessa Ortiz López

    2012-12-01

    Full Text Available This paper is a review of the legislative elections held in Colombia in 2010 and one of their main results, the establishment of the National Integration Party (PIN. The authors offer an analysis of articles that appeared in printed media, taking into consideration such variables as financing, legal constitution, popular acceptance and settling time. In this way, the authors attempt to demonstrate how the PIN managed to get a place in the political system and what are the consequences of this development, in particular, as the Department of Valle del Cauca is concerned.

  6. Analysis of the porosity distribution of mixed oxide pins

    International Nuclear Information System (INIS)

    Lieblich, M.; Lopez, J.

    1987-01-01

    In the frame of the Joint Irradiation Program IVO-FR2-Vg7 between the Centre of Nuclear Research of Karlsruhe (KfK), the irradiation of 30 mixed-oxide fuel rods in the FR2 experimental reactor was carried out. The pins were located in 10 single-walled NaK capsules. The behaviour of the fuel during its burnup was studied, mainly, the rest-porosity and cracking distribution in the pellet, partial densification, etc. In this work 3 pins from the capsule No. 165 were analyzed. The experimental results (pore and cracking profiles) were interpreted by the fuel rod code SATURN. (Author) 20 refs

  7. Overexpression of PvPin1, a Bamboo Homolog of PIN1-Type Parvulin 1, Delays Flowering Time in Transgenic Arabidopsis and Rice

    Directory of Open Access Journals (Sweden)

    Zhigang Zheng

    2017-09-01

    Full Text Available Because of the long and unpredictable flowering period in bamboo, the molecular mechanism of bamboo flowering is unclear. Recent study showed that Arabidopsis PIN1-type parvulin 1 (Pin1At is an important floral activator and regulates floral transition by facilitating the cis/trans isomerization of the phosphorylated Ser/Thr residues preceding proline motifs in suppressor of overexpression of CO 1 (SOC1 and agamous-like 24 (AGL24. Whether bamboo has a Pin1 homolog and whether it works in bamboo flowering are still unknown. In this study, we cloned PvPin1, a homolog of Pin1At, from Phyllostachys violascens (Bambusoideae. Bioinformatics analysis showed that PvPin1 is closely related to Pin1-like proteins in monocots. PvPin1 was widely expressed in all tested bamboo tissues, with the highest expression in young leaf and lowest in floral bud. Moreover, PvPin1 expression was high in leaves before bamboo flowering then declined during flower development. Overexpression of PvPin1 significantly delayed flowering time by downregulating SOC1 and AGL24 expression in Arabidopsis under greenhouse conditions and conferred a significantly late flowering phenotype by upregulating OsMADS56 in rice under field conditions. PvPin1 showed subcellular localization in both the nucleus and cytolemma. The 1500-bp sequence of the PvPin1 promoter was cloned, and cis-acting element prediction showed that ABRE and TGACG-motif elements, which responded to abscisic acid (ABA and methyl jasmonate (MeJA, respectively, were characteristic of P. violascens in comparison with Arabidopsis. On promoter activity analysis, exogenous ABA and MeJA could significantly inhibit PvPin1 expression. These findings suggested that PvPin1 may be a repressor in flowering, and its delay of flowering time could be regulated by ABA and MeJA in bamboo.

  8. Overexpression of PvPin1, a Bamboo Homolog of PIN1-Type Parvulin 1, Delays Flowering Time in Transgenic Arabidopsis and Rice.

    Science.gov (United States)

    Zheng, Zhigang; Yang, Xiaoming; Fu, Yaping; Zhu, Longfei; Wei, Hantian; Lin, Xinchun

    2017-01-01

    Because of the long and unpredictable flowering period in bamboo, the molecular mechanism of bamboo flowering is unclear. Recent study showed that Arabidopsis PIN1-type parvulin 1 (Pin1At) is an important floral activator and regulates floral transition by facilitating the cis/trans isomerization of the phosphorylated Ser/Thr residues preceding proline motifs in suppressor of overexpression of CO 1 (SOC1) and agamous-like 24 (AGL24). Whether bamboo has a Pin1 homolog and whether it works in bamboo flowering are still unknown. In this study, we cloned PvPin1 , a homolog of Pin1At , from Phyllostachys violascens (Bambusoideae). Bioinformatics analysis showed that PvPin1 is closely related to Pin1-like proteins in monocots. PvPin1 was widely expressed in all tested bamboo tissues, with the highest expression in young leaf and lowest in floral bud. Moreover, PvPin1 expression was high in leaves before bamboo flowering then declined during flower development. Overexpression of PvPin1 significantly delayed flowering time by downregulating SOC1 and AGL24 expression in Arabidopsis under greenhouse conditions and conferred a significantly late flowering phenotype by upregulating OsMADS56 in rice under field conditions. PvPin1 showed subcellular localization in both the nucleus and cytolemma. The 1500-bp sequence of the PvPin1 promoter was cloned, and cis -acting element prediction showed that ABRE and TGACG-motif elements, which responded to abscisic acid (ABA) and methyl jasmonate (MeJA), respectively, were characteristic of P. violascens in comparison with Arabidopsis . On promoter activity analysis, exogenous ABA and MeJA could significantly inhibit PvPin1 expression. These findings suggested that PvPin1 may be a repressor in flowering, and its delay of flowering time could be regulated by ABA and MeJA in bamboo.

  9. CODA : Compact front-end analog ASIC for silicon detectors

    International Nuclear Information System (INIS)

    Chandratre, V.B.; Sardesai, S.V.; Kataria, S.K.

    2004-01-01

    The paper presents the design of a front-end signal processing ASIC to be used with Silicon detectors having full depletion capacitance up to 40 pf. The ASIC channel consists of a charge amplifier, a shaper amplifier (CR-RC 3 ) and a comparator. There is provision for changing gain and polarity. The circuit has an estimated power dissipation of 16 mw. The ASIC is fabricated in 1.2 um CMOS technology. The 0pf noise is ∼400e. The chip has an area of 3 by 4 mm is packaged in 48 pin CLCC and COB option (Chip on Board). (author)

  10. Oxygen-induced inhibition of silicon-on-insulator dewetting

    Energy Technology Data Exchange (ETDEWEB)

    Curiotto, S.; Leroy, F.; Cheynis, F.; Müller, P. [Aix Marseille Université, CNRS, CINaM UMR 7325, 13288 Marseille (France)

    2014-02-10

    We report that solid state dewetting of Si thin film on SiO{sub 2} can be reversibly inhibited by exposing the Si surface to a partial pressure of dioxygen (∼10{sup −7}Torr) at high temperature (∼1100K). Coupling in situ Low-Energy Electron Microscopy and ex situ atomic force microscopy we propose that the pinning of the contact line induced by the presence of small amounts of silicon oxide is the main physical process that inhibits the dewetting.

  11. Assessment of pin-by-pin fission rate distribution within MOX/UO{sub 2} fuel assembly using MCNPX code

    Energy Technology Data Exchange (ETDEWEB)

    Louis, Heba Kareem; Amin, Esmat [Nuclear and Radiological Regulation Authority (NRRA), Cairo (Egypt). Safety Engineering Dept.

    2016-03-15

    The aim of the present paper is to assess the calculations of pin-by-pin group integrated fission rates within MOX/UO{sub 2} Fuel assemblies using the Monte Carlo code MCNP2.7c with two sets of the available latest nuclear data libraries used for calculating MOX-fueled systems. The data that are used in this paper are based on the benchmark by the NEA Nuclear Science Committee (NSC). The k{sub ∞} and absorption/fission reaction rates per isotope, k{sub eff} and pin-by-pin group integrated fission rates on 1/8 fraction of the geometry are determined. To assess the overall pin-by-pin fission rate distribution, the collective per cent error measures were investigated. The results of AVG, MRE and RMS error measures were less than 1 % error. The present results are compared with other participants using other Monte Carlo codes and with CEA results that were taken in the benchmark as reference. The results with ENDF/B-VI.6 are close to the results received by MVP (JENDL3.2) and SCALE 4.2 (JEF2.2). The results with ENDF/BVII.1 give higher values of k{sub ∞} reflecting the changes in the newer evaluations. In almost all results presented here, the MCNP calculated results with ENDF/B VII.1 should be considered more than those obtained by using other Monte Carlo codes and nuclear data libraries. The present calculations may be consider a reference for evaluating the numerical schemes in production code systems, as well as the global performance including cross-section data reduction methods as the calculations used continuous energy and no geometrical approximations.

  12. Electron Beam Induced Radiation Damage of the Semiconductor Radiation Detector based on Silicon

    International Nuclear Information System (INIS)

    Kim, Han Soo; Kim, Yong Kyun; Park, Se Hwan; Haa, Jang Ho; Kang, Sang Mook; Chung, Chong Eun; Cho, Seung Yeon; Park, Ji Hyun; Yoon, Tae Hyung

    2005-01-01

    A Silicon Surface Barrier (SSB) semiconductor detector which is generally used to detect a charged particle such as an alpha particle was developed. The performance of the developed SSB semiconductor detector was measured with an I-V curve and an alpha spectrum. The response for an alpha particle was measured by Pu-238 sources. A SSB semiconductor detector was irradiated firstly at 30sec, at 30μA and secondly 40sec, 40μA with a 2MeV pulsed electron beam generator in KAERI. And the electron beam induced radiation damage of a homemade SSB detector and the commercially available PIN photodiode were investigated. An annealing effect of the damaged SSB and PIN diode detector were also investigated using a Rapid Thermal Annealing (RTA). This data may assist in designing the silicon based semiconductor radiation detector when it is operated in a high radiation field such as space or a nuclear power plant

  13. Study of the properties of silicon-based semiconductor converters for betavoltaic cells

    International Nuclear Information System (INIS)

    Polikarpov, M. A.; Yakimov, E. B.

    2015-01-01

    Silicon p-i-n diodes are studied in a scanning electron microscope under conditions simulating the β-radiation from a radioactive Ni 63 source with an activity of 10 mCi/cm 2 . The attainable parameters of β-voltaic cells with a source of this kind and a silicon-based converter of β-particle energy to electric current are estimated. It is shown that the power of elements of this kind can reach values of ∼10 nW/cm 2 even for a cell with an area of one centimeter, which is rather close to the calculated value

  14. Evaluation of PWR and BWR pin cell benchmark results

    International Nuclear Information System (INIS)

    Pijlgroms, B.J.; Gruppelaar, H.; Janssen, A.J.; Hoogenboom, J.E.; Leege, P.F.A. de; Voet, J. van der; Verhagen, F.C.M.

    1991-12-01

    Benchmark results of the Dutch PINK working group on PWR and BWR pin cell calculational benchmark as defined by EPRI are presented and evaluated. The observed discrepancies are problem dependent: a part of the results is satisfactory, some other results require further analysis. A brief overview is given of the different code packages used in this analysis. (author). 14 refs., 9 figs., 30 tabs

  15. Evaluation of PWR and BWR pin cell benchmark results

    Energy Technology Data Exchange (ETDEWEB)

    Pijlgroms, B.J.; Gruppelaar, H.; Janssen, A.J. (Netherlands Energy Research Foundation (ECN), Petten (Netherlands)); Hoogenboom, J.E.; Leege, P.F.A. de (Interuniversitair Reactor Inst., Delft (Netherlands)); Voet, J. van der (Gemeenschappelijke Kernenergiecentrale Nederland NV, Dodewaard (Netherlands)); Verhagen, F.C.M. (Keuring van Electrotechnische Materialen NV, Arnhem (Netherlands))

    1991-12-01

    Benchmark results of the Dutch PINK working group on PWR and BWR pin cell calculational benchmark as defined by EPRI are presented and evaluated. The observed discrepancies are problem dependent: a part of the results is satisfactory, some other results require further analysis. A brief overview is given of the different code packages used in this analysis. (author). 14 refs., 9 figs., 30 tabs.

  16. Pinning and creep in high-Tc superconductors

    International Nuclear Information System (INIS)

    Ovchinnikov, Yu.N.; Ivlev, B.I.

    1992-01-01

    The angular and magnetic field dependence of a critical current parallel to the layers in the layered superconductors is studied. The critical current value is found for a superconductor with strong pinning centers. Quantum flux creep in sufficiently perfect layered high-Tc superconductors is discussed. The cross-over temperature between activated and quantum creep is found. (orig.)

  17. Percutaneous Pin Fixation of Gartland Type I11 Supraconylar ...

    African Journals Online (AJOL)

    S G Lungu M.Med (Orth). Specialist Orthopaedic Surgeon. Zambian Italian Orthopaedic Hospital, Lusaka. Key words: Percutaneous, pin fixation, Gartland type Ill, supracondylar, fractures, and humerus. This was a prospective study of 40 children with severely displaced (Gartland Type 111) supracondylar fractures of the ...

  18. Modeling the pinning of Au and Ni clusters on graphite

    NARCIS (Netherlands)

    Smith, R.; Nock, C.; Kenny, S.D.; Belbruno, J.J.; Di Vece, M.; Paloma, S.; Palmer, R.E.

    2006-01-01

    The pinning of size-selected AuN and NiN clusters on graphite, for N=7–100, is investigated by means of molecular dynamics simulations and the results are compared to experiment and previous work with Ag clusters. Ab initio calculations of the binding of the metal adatom and dimers on a graphite

  19. Flux pinning in MOD YBCO films by chemical doping

    International Nuclear Information System (INIS)

    Zhou, Y X; Ghalsasi, S; Rusakova, I; Salama, K

    2007-01-01

    A novel nanomaterial synthesis technique has been developed to introduce 0D (particles), 1D (columnar defects) and 3D (domains) nanoscale pinning centres in MOD Y 1 Ba 2 Cu 3 O 7 (YBCO) coated conductors. We have succeeded in introducing nanoscale Y enriched particles, nanoscale 90 0 rotated Y 1/3 Sm 2/3 Ba 2 Cu 3 O 7 domains and nanoscale Zr enriched columnar defects into YBCO layers by different chemical doping. The pinning force density in Y 2 O 3 -doped YBCO film is found to be larger than that of pure YBCO film at all fields. Also it was found that YBCO films with Sm substituting for Y have yielded improved critical current density characteristics over a wide range of magnetic fields. Maximum pinning force densities exceeding 7 and 8 GN m -3 are obtained in 5% BZO-doped and Sm substituted YBCO films, respectively. Additionally, TEM studies revealed nanoscale Zr enriched columnar defects distributing in the matrix of the c-oriented YBCO film throughout the whole cross section. This indicates that chemical doping is a promising fabrication technique to create specific pinning landscapes in YBCO coated conductors

  20. Temperature dependent pinning landscapes in REBCO thin films

    Science.gov (United States)

    Jaroszynski, Jan; Constantinescu, Anca-Monia; Hu, Xinbo Paul

    2015-03-01

    The pinning landscapes of REBCO (RE=rare earth elements) thin films have been a topic of study in recent years due to, among other reasons, their high ability to introduce various phases and defects. Pinning mechanisms studies in high temperature superconductors often require detailed knowledge of critical current density as a function of magnetic field orientation as well as field strength and temperature. Since the films can achieve remarkably high critical current, challenges exist in evaluating these low temperature (down to 4.2 K) properties in high magnetic fields up to 30 T. Therefore both conventional transport, and magnetization measurements in a vibrating coil magnetometer equipped with rotating sample platform were used to complement the study. Our results clearly show an evolution of pinning from strongly correlated effects seen at high temperatures to significant contributions from dense but weak pins that thermal fluctuations render ineffective at high temperatures but which become strong at lower temperatures Support for this work is provided by the NHMFL via NSF DRM 1157490

  1. Flux vortex dynamics and electric fields in matched pinning systems

    International Nuclear Information System (INIS)

    Blamire, M.G.

    1987-01-01

    The pinning of flux vortices in type II superconductors has been the subject of extensive research. Certain experiments have attempted to investigate this problem by the use of specially prepared pinning structures consisting of regular arrays of pinning centers. In this paper a theory relating to such experiments is described. This theory is based on the existence and properties of defects in an otherwise perfect vortex lattice which is commensurate with a pinning array consisting of a triangular lattice of holes in a superconducting thin film. A quantitative treatment predicts the existence and position of substructure on the critical current versus magnetic field curves in addition to the main peaks previously predicted to occur when the vortex and hole lattices are exactly matched. The theory also qualitatively describes the overall shape of these curves. An analysis of the temperature dependence of this substructure shows broad agreement with existing experimental results. The application of this theory to future experiments should allow a detailed investigation of vortex lattice elasticity and flux flow

  2. Performance of advanced oxide fuel pins in EBR-II

    International Nuclear Information System (INIS)

    Lawrence, L.A.; Jensen, S.M.; Hales, J.W.; Karnesky, R.A.; Makenas, B.J.

    1986-05-01

    The effects of design and operating parameters on mixed-oxide fuel pin irradiation performance were established for the Hanford Engineering Development Laboratory (HEDL) advanced oxide EBR-II test series. Fourteen fuel pins breached in-reactor with reference 316 SS cladding. Seven of the breaches are attributed to FCMI. Of the remaining seven breached pins, three are attributed to local cladding over-temperatures similar to the breach mechanism for the reference oxide pins irradiated in EBR-II. FCCI was found to be a contributing factor in two high burnup, i.e., 11.7 at. % breaches. The remaining two breaches were attributed to mechanical interaction of UO 2 fuel and fission products accumulated in the lower cladding insulator gap, and a loss of cladding ductility possibly due to liquid metal embrittlement. Fuel smear density appears to have the most significant impact on lifetime. Quantitative evaluations of cladding diameter increases attributed to FCMI, established fuel smear density, burnup, and cladding thickness-to-diameter ratio as the major parameters influencing the extent of cladding strain

  3. Image analysis for remote examination of fuel pins

    International Nuclear Information System (INIS)

    Cook, J.H.; Nayak, U.P.

    1982-01-01

    An image analysis system operating in the Wing 9 Hot Cell Facility at Los Alamos National Laboratory provides quantitative microstructural analyses of irradiated fuels and materials. With this system, fewer photomicrographs are required during postirradiation microstructural examination and data are available for analysis much faster. The system has been used successfully to examine Westinghouse Advanced Reactors Division experimental fuel pins

  4. Flux-Vortex Pinning and Neutron Star Evolution

    Indian Academy of Sciences (India)

    M. Ali Alpar

    2017-09-12

    Sep 12, 2017 ... M. ALI ALPAR. Faculty of Engineering and Natural Sciences, Sabancı University, 34956, Istanbul, Turkey. E-mail: ... netic field of the neutron star were B ∼ 109 G. At the ..... across pinning energy barriers by thermal activation.

  5. The behaviour of Phenix fuel pin bundle under irradiation

    International Nuclear Information System (INIS)

    Marbach, G.; Millet, P.; Blanchard, P.; Huillery, R.

    1979-07-01

    An entire Phenix sub-assembly has been mounted and sectioned after irradiation. The examination of cross-sections revealed the effects of mechanical interaction in the bundle (ovalisations and contacts between clads). According to analysis of the sodium channels, cooling of the pin bundle remained uniform. (author)

  6. Pin Tract Infection after Uniplanar External Fixation of Open ...

    African Journals Online (AJOL)

    ADMIN

    Regionally, a study by Jellis et al in Lusaka, Zambia, compared the rate of severe pin tract infection in HIV negative and positive ... likelihood of infection such as human immunodeficiency virus infection, diabetes mellitus, liver failure, renal failure, tumours ... Combined Open Tibia-Fibular. And Femur Fractures. 2. 2.7. Totals.

  7. Review of HEDL fuel pin transient analyses analytical programs

    International Nuclear Information System (INIS)

    Scott, J.H.; Baars, R.E.

    1975-05-01

    Methods for analysis of transient fuel pin performance are described, as represented by the steady-state SIEX code and the PECT series of codes used for steady-state and transient mechanical analyses. The empirical fuel failure correlation currently in use for analysis of transient overpower accidents is described. (U.S.)

  8. Propagation of spiral waves pinned to circular and rectangular obstacles.

    Science.gov (United States)

    Sutthiopad, Malee; Luengviriya, Jiraporn; Porjai, Porramain; Phantu, Metinee; Kanchanawarin, Jarin; Müller, Stefan C; Luengviriya, Chaiya

    2015-05-01

    We present an investigation of spiral waves pinned to circular and rectangular obstacles with different circumferences in both thin layers of the Belousov-Zhabotinsky reaction and numerical simulations with the Oregonator model. For circular objects, the area always increases with the circumference. In contrast, we varied the circumference of rectangles with equal areas by adjusting their width w and height h. For both obstacle forms, the propagating parameters (i.e., wavelength, wave period, and velocity of pinned spiral waves) increase with the circumference, regardless of the obstacle area. Despite these common features of the parameters, the forms of pinned spiral waves depend on the obstacle shapes. The structures of spiral waves pinned to circles as well as rectangles with the ratio w/h∼1 are similar to Archimedean spirals. When w/h increases, deformations of the spiral shapes are observed. For extremely thin rectangles with w/h≫1, these shapes can be constructed by employing semicircles with different radii which relate to the obstacle width and the core diameter of free spirals.

  9. Neutron radiography for quality assurance of PHWR fuel pins

    International Nuclear Information System (INIS)

    Chandrasekharan, K.N.; Patil, B.P.; Ghosh, J.K.; Ganguly, C.

    1993-01-01

    Neutron radiography was employed for quality assurance (QA) for advanced PHWR experimental fuel pins containing mixed uranium-plutonium dioxide and thorium-plutonium dioxide pellets. Direct, transfer and track-etch techniques were utilised. The thermal neutron beam facility of APSARA research reactor at Bhabha Atomic Research Centre was used. (author). 5 refs., 16 figs., 2 tabs

  10. Calculation of fuel pin failure timing under LOCA conditions

    International Nuclear Information System (INIS)

    Jones, K.R.; Wade, N.L.; Siefken, L.J.; Straka, M.; Katsma, K.R.

    1991-10-01

    The objective of this research was to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B ampersand W) design (Oconee) and a Westinghouse (W) 4-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin burnup, axial peaking factor, break size, emergency core cooling system (ECCS) availability, and main coolant pump trip on these items. The analysis was performed using a four-code approach, comprised of FRAPCON-2, SCDAP/RELAP5/MOD3, TRAC-PF1/MOD1, and FRAP-T6. In addition to the calculation of timing results, this analysis provided a comparison of the capabilities of SCDAP/RELAP5/MOD3 with TRAC-PF1/MOD1 for large-break LOCA analysis. This paper discusses the methodology employed and the code development efforts required to implement the methodology. The shortest time intervals calculated between initiation of containment isolation and fuel pin failure were 11.4 s and 19.1 for the B ampersand W and W plants, respectively. The FRAP-T6 fuel pin failure times calculated using thermal-hydraulic data generated by SCDAP/RELAP5/MOD3 were more conservative than those calculated using data generated by TRAC-PF1/MOD1. 18 refs., 7 figs., 4 tabs

  11. Investigation on flow and heat transfer characteristics in rectangular channel with drop-shaped pin fins

    Directory of Open Access Journals (Sweden)

    Fengming Wang

    2012-12-01

    Full Text Available The flow and heat transfer characteristics inside a rectangular channel embedded with pin fins were numerically and experimentally investigated. Several differently shaped pin fins (i.e., circular, elliptical, and drop-shaped with the same cross-sectional areas were compared in a staggered arrangement. The Reynolds number based on the obstructed section hydraulic diameter (defined as the ratio of the total wetted surface area to the open duct volume available for flow was varied from 4800 to 8200. The more streamlined drop-shaped pin fins were better at delaying or suppressing separation of the flow passing through them, which decreased the aerodynamic penalty compared to circular pin fins. The heat transfer enhancement of the drop-shaped pin fins was less than that of the circular pin fins. In terms of specific performance parameters, drop-shaped pin fins are a promising alternative configuration to circular pin fins.

  12. Vortex Dynamics in Superconductors with Different Types of Pinning Potentials

    International Nuclear Information System (INIS)

    Laguna, Maria Fabiana

    2001-01-01

    In this work we study the behavior of the vortex system in the mixed state of a type II superconductor when it interacts with different kinds of pinning potentials. To do this, we perform numerical simulations in the presence of an external magnetic field, by making use of two different approaches.One corresponds to a Langevin simulation of the three dimensional XY model or Josephson-junction network, whereas the other corresponds to a Molecular dynamics simulation of two dimensional point-like vortices.We analyze the transport properties of highly anisotropic superconductors with different kinds of topological disorder in the configuration in which the external field is applied perpendicular to the CuO planes.We found that for systems with point defects the activation energy is the same for the two components of the resistivity, while in systems with columnar defects the activation energies can be different.We also study the structure, phase transitions and transport properties of the vortex system when the external magnetic field lies parallel to the planes in layered superconductors. We analyze the stability of different phases at low temperatures and show under which conditions the smectic phase is stable.Our results indicate the presence of the smectic phase in an intermediate range of temperatures.We have studied a vortex array in a periodic pinning potential with triangular and kagome geometries.We obtain the ground state vortex configurations and calculate some thermodynamic quantities for different magnetic fields.We observe several stages of lattice pinning and melting and we characterize different phases and transitions between them.Finally, simulating the Bitter pinning effect over the vortex system, we study static and dynamic properties of the vortex system in the presence of the surface Bitter pinning and the bulk pinning.We found low temperature structures similar to those obtained experimentally.We analyze the dynamics of the nucleation and growth

  13. One- and two-dimension effects on fuel pin lifetime

    International Nuclear Information System (INIS)

    Stephen, J.D.; Biancheria, A.; Leibnitz, D.; O'Reilly, B.D.; Liu, Y.Y.; Labar, M.P.; Gneiting, B.C.

    1979-01-01

    Lifetime, or breach of the cladding, is a difficult performance limit to establish in fuel pin design. The significant benefits of high plant capacity factor favor conservative design to eliminate downtime or partial power operation caused by the breach limit; however, overly conservative design produces significant penalties. The LIFE system is being applied to help understand the range between operation and breach so that appropriate design margins can be selected. Standards are being developed in the USA to assure the structural integrity of all core components. These standards will provide guidelines to account for the failure mechanisms observed in the high temperature, high fluence core environment. The work to date indicates that creep rupture is the most important failure mechanism for mixed-oxide fuel pins during normal operation and slow power changes. The local cumulative creep rupture damage fraction (CDF) has been adopted as the parameter to assess the approach to failure. Several oxide breached pins and siblings have been studied For example, the P23B-73 pin was an FFTR driver design pin irradiated in EBR-II which failed at 10 at,% burnup. Initial evaluation based on LIFE3 led to the conclusion that the pin should not have failed. Further analyses determined the sensitivity of the breach prediction to the time-to-rupture correlation, cladding temperature, and fuel-fission product swelling (which had not been modeled in LIFE3). The uncertainties in the time-to-rupture correlation have been established. But LIFE is a one-dimensional model. The TWOD code is complete, and development of the best way to couple LIFE and TWOD for lifetime analysis is in progress. Two preliminary conclusions from analysis of representative oxide pin geometries are, first, that the circumferential stress distribution may not peak at the hot spot, but the damage (CDF) does. And second, that the effect of stress concentrations near fuel cracks on cladding creep damage is small

  14. Works of art investigation with silicon drift detectors

    CERN Document Server

    Leutenegger, P; Fiorini, C; Strüder, L; Kemmer, J; Lechner, P; Sciuti, S; Cesareo, R

    2000-01-01

    The X-ray fluorescence (XRF) spectroscopy analysis is a non-destructive technique widely used in archeometry to investigate the chemical composition of pigments, metal alloys and stones for restoration and historical investigation. The classical detection systems for archeometrical investigations utilize cryogenic detectors, like Si(Li) and HPGe, characterized by a satisfactory energy resolution (of the order of 140 eV FWHM at 6 keV). However, the requirements of liquid N sub 2 drastically limit the portability of such systems, limiting the possibility of making measurements 'on the field'. Recently new silicon PIN diodes Peltier cooled were introduced, allowing the construction of portable instrumentation. However, their energy resolution (of the order of 250 eV FWHM at 6 keV) results in some cases unsatisfactory (for instance in the identification of light elements). Both the requirements of portability and good energy resolution are fulfilled by the silicon drift detector (SDD). The SDD, cooled by a Peltie...

  15. Transfixation pinning and casting of radial-ulnar fractures in calves: A review of three cases

    OpenAIRE

    St-Jean, Guy; Debowes, Richard M.

    1992-01-01

    We reviewed the medical records of three calves with radial-ulnar fractures which were reduced and stabilized by transfixation pinning and casting. Multiple Steinmann pins were placed transversely through proximal and distal fracture fragments and the pin ends were incorporated in fiberglass cast material after fracture reduction. Cast material was placed from proximal to distal radius and served as an external frame to maintain pin position and fracture reduction.

  16. Serviceability of rod ceramic fuel pins on motoring conditions of FTP or NEMF reactor

    International Nuclear Information System (INIS)

    Deryavko, I.I.

    2004-01-01

    The operation conditions of rod ceramic fuel pins in the running hydrogen-cooled technological canals of FTP or NEMF reactor on the motoring conditions are considered. The available postreactor researches of the fuel pins are presented and the additional postreactor researches of fuel pins, tested on this mode in IVG.1 and IRGIT reactors, are carried out. The fuel pins serviceability on motoring conditions of FTP or NEF reactor operation is concluded. (author)

  17. Chiral silicon nanostructures

    International Nuclear Information System (INIS)

    Schubert, E.; Fahlteich, J.; Hoeche, Th.; Wagner, G.; Rauschenbach, B.

    2006-01-01

    Glancing angle ion beam assisted deposition is used for the growth of amorphous silicon nanospirals onto [0 0 1] silicon substrates in a temperature range from room temperature to 475 deg. C. The nanostructures are post-growth annealed in an argon atmosphere at various temperatures ranging from 400 deg. C to 800 deg. C. Recrystallization of silicon within the persisting nanospiral configuration is demonstrated for annealing temperatures above 800 deg. C. Transmission electron microscopy and Raman spectroscopy are used to characterize the silicon samples prior and after temperature treatment

  18. Silicon web process development

    Science.gov (United States)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Skutch, M. E.; Driggers, J. M.; Hopkins, R. H.

    1981-01-01

    The silicon web process takes advantage of natural crystallographic stabilizing forces to grow long, thin single crystal ribbons directly from liquid silicon. The ribbon, or web, is formed by the solidification of a liquid film supported by surface tension between two silicon filaments, called dendrites, which border the edges of the growing strip. The ribbon can be propagated indefinitely by replenishing the liquid silicon as it is transformed to crystal. The dendritic web process has several advantages for achieving low cost, high efficiency solar cells. These advantages are discussed.

  19. New Universal Tribometer as Pin or Ball-on-Disc and Reciprocating Pin-on-Plate Types

    Directory of Open Access Journals (Sweden)

    H. Kaleli

    2016-06-01

    Full Text Available The present paper contains a description of a new Universal Tribometer design which enables simulation of different contact and test types such as pin-on-disc, ball-on-disc and linear reciprocating tests. There are many models of wear Tribometer in the world market. These devices are manufactured by various companies abroad and are imported to our country. Cost of this devices start from 50.000 euros and goes to hundreds of thousands of euros. One of the most commonly used of this device is Reciprocating Pin-on-Plate Tribo Test Machine. This wear tester is produced at a low limited cost within the KAP (Scientifical Research Project Coordinator of Yıldız Technical University. The test machine can work including three types of Tribotest rigs (Reciprocating Pin-on-Plate, Pin-on-Disc and Ball-on-Disc. It is designed to operate also at high temperatures up to 500 ˚C. The new piece of equipment allows instrumented tribological testing of piston ring and cylinder liner samples at low and high temperatures and boundary lubrication conditions of any typical gasoline or Diesel engines. Some friction results were shown in boundary lubricating conditions between piston ring and cylinder liner sliding pairs describing Tribotest machine is driven by AC servo motor which is more accurate than DC motor.

  20. Development of spectral history methods for pin-by-pin core analysis method using three-dimensional direct response matrix

    International Nuclear Information System (INIS)

    Mitsuyasu, T.; Ishii, K.; Hino, T.; Aoyama, M.

    2009-01-01

    Spectral history methods for pin-by-pin core analysis method using the three-dimensional direct response matrix have been developed. The direct response matrix is formalized by four sub-response matrices in order to respond to a core eigenvalue k and thus can be recomposed at each outer iteration in the core analysis. For core analysis, it is necessary to take into account the burn-up effect related to spectral history. One of the methods is to evaluate the nodal burn-up spectrum obtained using the out-going neutron current. The other is to correct the fuel rod neutron production rates obtained the pin-by-pin correction. These spectral history methods were tested in a heterogeneous system. The test results show that the neutron multiplication factor error can be reduced by half during burn-up, the nodal neutron production rates errors can be reduced by 30% or more. The root-mean-square differences between the relative fuel rod neutron production rate distributions can be reduced within 1.1% error. This means that these methods can accurately reflect the effects of intra- and inter-assembly heterogeneities during burn-up and can be used for core analysis. Core analysis with the DRM method was carried out for an ABWR quarter core and it was found that both thermal power and coolant-flow distributions were smoothly converged. (authors)

  1. Fluctuation microscopy analysis of amorphous silicon models

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, J.M., E-mail: jmgibson@fsu.edu [Northeastern University, Department of Physics, Boston MA 02115 (United States); FAMU/FSU Joint College of Engineering, 225 Pottsdamer Street, Tallahassee, FL 32310 (United States); Treacy, M.M.J. [Arizona State University, Department of Physics, Tempe AZ 85287 (United States)

    2017-05-15

    Highlights: • Studied competing computer models for amorphous silicon and simulated fluctuation microscopy data. • Show that only paracrystalline/random network composite can fit published data. • Specifically show that pure random network or random network with void models do not fit available data. • Identify a new means to measure volume fraction of ordered material. • Identify unreported limitations of the Debye model for simulating fluctuation microscopy data. - Abstract: Using computer-generated models we discuss the use of fluctuation electron microscopy (FEM) to identify the structure of amorphous silicon. We show that a combination of variable resolution FEM to measure the correlation length, with correlograph analysis to obtain the structural motif, can pin down structural correlations. We introduce the method of correlograph variance as a promising means of independently measuring the volume fraction of a paracrystalline composite. From comparisons with published data, we affirm that only a composite material of paracrystalline and continuous random network that is substantially paracrystalline could explain the existing experimental data, and point the way to more precise measurements on amorphous semiconductors. The results are of general interest for other classes of disordered materials.

  2. Fluctuation microscopy analysis of amorphous silicon models

    International Nuclear Information System (INIS)

    Gibson, J.M.; Treacy, M.M.J.

    2017-01-01

    Highlights: • Studied competing computer models for amorphous silicon and simulated fluctuation microscopy data. • Show that only paracrystalline/random network composite can fit published data. • Specifically show that pure random network or random network with void models do not fit available data. • Identify a new means to measure volume fraction of ordered material. • Identify unreported limitations of the Debye model for simulating fluctuation microscopy data. - Abstract: Using computer-generated models we discuss the use of fluctuation electron microscopy (FEM) to identify the structure of amorphous silicon. We show that a combination of variable resolution FEM to measure the correlation length, with correlograph analysis to obtain the structural motif, can pin down structural correlations. We introduce the method of correlograph variance as a promising means of independently measuring the volume fraction of a paracrystalline composite. From comparisons with published data, we affirm that only a composite material of paracrystalline and continuous random network that is substantially paracrystalline could explain the existing experimental data, and point the way to more precise measurements on amorphous semiconductors. The results are of general interest for other classes of disordered materials.

  3. High-performance silicon nanowire bipolar phototransistors

    Science.gov (United States)

    Tan, Siew Li; Zhao, Xingyan; Chen, Kaixiang; Crozier, Kenneth B.; Dan, Yaping

    2016-07-01

    Silicon nanowires (SiNWs) have emerged as sensitive absorbing materials for photodetection at wavelengths ranging from ultraviolet (UV) to the near infrared. Most of the reports on SiNW photodetectors are based on photoconductor, photodiode, or field-effect transistor device structures. These SiNW devices each have their own advantages and trade-offs in optical gain, response time, operating voltage, and dark current noise. Here, we report on the experimental realization of single SiNW bipolar phototransistors on silicon-on-insulator substrates. Our SiNW devices are based on bipolar transistor structures with an optically injected base region and are fabricated using CMOS-compatible processes. The experimentally measured optoelectronic characteristics of the SiNW phototransistors are in good agreement with simulation results. The SiNW phototransistors exhibit significantly enhanced response to UV and visible light, compared with typical Si p-i-n photodiodes. The near infrared responsivities of the SiNW phototransistors are comparable to those of Si avalanche photodiodes but are achieved at much lower operating voltages. Compared with other reported SiNW photodetectors as well as conventional bulk Si photodiodes and phototransistors, the SiNW phototransistors in this work demonstrate the combined advantages of high gain, high photoresponse, low dark current, and low operating voltage.

  4. Design fix for vibration-induced wear in fuel pin bundles

    International Nuclear Information System (INIS)

    Naas, D.F.; Heck, E.N.

    1976-01-01

    In summary, results at 45,000 MWd/MTM burnup from the FFTF mixed oxide fuel pin irradiation tests in EBR-II show that reduction of the initial fuel pin bundle clearance and use of 20 percent cold-worked stainless steel ducts virtually eliminate vibration and wear observed in an initial series of 61-pin tests

  5. The Effect of Insertion Technique on Temperatures for Standard and Self-Drilling External Fixation Pins.

    Science.gov (United States)

    Manoogian, Sarah; Lee, Adam K; Widmaier, James C

    2017-08-01

    No studies have assessed the effects of parameters associated with insertion temperature in modern self-drilling external fixation pins. The current study assessed how varying the presence of irrigation, insertion speed, and force impacted the insertion temperatures of 2 types of standard and self-drilling external fixation half pins. Seventy tests were conducted with 10 trials for 4 conditions on self-drilling pins, and 3 conditions for standard pins. Each test used a thermocouple inside the pin to measure temperature rise during insertion. Adding irrigation to the standard pin insertion significantly lowered the maximum temperature (P drilling pin tests dropped average rise in temperature from 151.3 ± 21.6°C to 124.1 ± 15.3°C (P = 0.005). When the self-drilling pin insertion was decreased considerably from 360 to 60 rpm, the temperature decreased significantly from 151.3 ± 21.6°C to 109.6 ± 14.0°C (P drilling pin temperature increase was not significant. The standard pin had lower peak temperatures than the self-drilling pin for all conditions. Moreover, slowing down the insertion speed and adding irrigation helped mitigate the temperature increase of both pin types during insertion.

  6. Use of a modified transfixation pin cast for treatment of comminuted phalangeal fractures in horses.

    Science.gov (United States)

    Rossignol, Fabrice; Vitte, Amélie; Boening, Josef

    2014-01-01

    To (1) report a modified transfixation pin cast technique, using dorsal recumbency for fracture reduction, distal positioning of the pins in the epiphysis and distal metaphysis, and a hybrid cast, combining plaster of Paris (POP) and fiberglass casting, and (2) report outcome in 11 adult horses. Case series. Adult horses (n = 11) with comminuted phalangeal fractures. Horses were anesthetized and positioned in dorsal recumbency. The phalangeal fracture was reduced by limb traction using a cable attached to the hoof. Screw fixation in lag fashion of fracture fragments was performed when possible. Transfixation casting was performed using two 6.3 mm positive profile centrally threaded pins with the 1st pin placed in the epiphysis of the metacarpus/tarsus at the center of, or slightly proximal to, the condylar fossa and the 2nd one 3-4 cm proximal. A hybrid cast was applied. Forelimbs were involved in 9 horses and the hind limb in 2. Pins were maintained for a minimum of 6 weeks. No pin loosening was observed at the time of removal (6-8 weeks). A pony fractured the distal aspect of the metacarpus at the proximal pin. Nine horses survived (82%); none of the horses developed septic arthritis despite the distal location of the distal pin, close to the fetlock joint. This modified transfixation pin casting technique was associated with good pin longevity and could reduce the risk of secondary pin hole fractures and pin loosening. © Copyright 2013 by The American College of Veterinary Surgeons.

  7. A pin-assisted retention technique for resin-bonded restorations.

    Science.gov (United States)

    Miara, P; Touati, B

    1992-09-01

    The value of pins for auxiliary retention has been demonstrated many times. The use of pins with resin-bonded restorations allows for improved aesthetics and less tooth reduction while increasing resistance to dislodging forces. Clinical and technical procedures for resin-bonded bridges with pin-assisted retention are presented.

  8. The PIN family of proteins in potato and their putative role in tuberisation

    Directory of Open Access Journals (Sweden)

    Efstathios eRoumeliotis

    2013-12-01

    Full Text Available The PIN family of trans-membrane proteins mediates auxin efflux throughout the plant and during various phases of plant development. In Arabidopsis thaliana, the PIN family comprised of 8 members, divided into ‘short’ and ‘long’ PINs according to the length of the hydrophilic domain of the protein. Based on sequence homology using the recently published potato genome sequence (Solanum tuberosum group Phureja we identified ten annotated potato StPIN genes. Mining the publicly available gene expression data, we constructed a catalogue tissue specificity of StPIN gene expression, focusing on the process of tuberization. A total of four StPIN genes exhibited increased expression four days after tuber induction, prior to the onset of stolon swelling. For two PIN genes, StPIN4 and StPIN2, promoter sequences were cloned and fused to the GUS reporter protein to study tissue specificity in more detail. StPIN4 promoter driven GUS staining was detected in the flower stigma, in the flower style, below the ovary and petals, in the root tips, in the vascular tissue of the stolons and in the tuber parenchyma cells. StPIN2 promoter driven GUS staining was detected in flower buds, in the vascular tissue of the swelling stolons and in the storage parenchyma of the growing tubers. Based on our results, we postulate a role for the StPINs in redistributing auxin in the swelling stolon during early events in tuber development.

  9. Probabilistic distributions of pin gaps within a wire-spaced fuel subassembly and sensitivities of the related uncertainties to pin gap

    International Nuclear Information System (INIS)

    Sakai, K.; Hishida, H.

    1978-01-01

    Probabilistic fuel pin gap distributions within a wire-spaced fuel subassembly and sensitivities of the related uncertainties to fuel pin gaps are discussed. The analyses consist mainly of expressing a local fuel pin gap in terms of sensitivity functions of the related uncertainties and calculating the corresponding probabilistic distribution through taking all the possible combinations of the distribution of uncertainties. The results of illustrative calculations show that with the reliability level of 0.9987, the maximum deviation of the pin gap at the cladding hot spot of a center fuel subassembly is 8.05% from its nominal value and the corresponding probabilistic pin gap distribution is shifted to the narrower side due to the external confinement of a pin bundle with a wrapper tube. (Auth.)

  10. Percutaneous external fixator pins with bactericidal micron-thin sol-gel films for the prevention of pin tract infection.

    Science.gov (United States)

    Qu, Haibo; Knabe, Christine; Radin, Shula; Garino, Jonathan; Ducheyne, Paul

    2015-09-01

    Risk of infection is considerable in open fractures, especially when fracture fixation devices are used to stabilize the fractured bones. Overall deep infection rates of 16.2% have been reported. The infection rate is even greater, up to 32.2%, with external fixation of femoral fractures. The use of percutaneous implants for certain clinical applications, such as percutaneous implants for external fracture fixation, still represents a challenge today. Currently, bone infections are very difficult to treat. Very potent antibiotics are needed, which creates the risk of irreversible damage to other organs, when the antibiotics are administered systemically. As such, controlled, local release is being pursued, but no such treatments are in clinical use. Herein, the use of bactericidal micron-thin sol-gel films on metallic fracture fixation pins is reported. The data demonstrates that triclosan (2,4,4'-trichloro-2'-hydroxydiphenylether), an antimicrobial agent, can be successfully incorporated into micron-thin sol-gel films deposited on percutaneous pins. The sol-gel films continuously release triclosan in vitro for durations exceeding 8 weeks (longest measured time point). The bactericidal effect of the micron-thin sol-gel films follows from both in vitro and in vivo studies. Inserting percutaneous pins in distal rabbit tibiae, there were no signs of infection around implants coated with a micron-thin sol-gel/triclosan film. Healing had progressed normally, bone tissue growth was normal and there was no epithelial downgrowth. This result was in contrast with the results in rabbits that received control, uncoated percutaneous pins, in which abundant signs of infection and epithelial downgrowth were observed. Thus, well-adherent, micron-thin sol-gel films laden with a bactericidal molecule successfully prevented pin tract infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Design and Performance of a Pinned Photodiode CMOS Image Sensor Using Reverse Substrate Bias.

    Science.gov (United States)

    Stefanov, Konstantin D; Clarke, Andrew S; Ivory, James; Holland, Andrew D

    2018-01-03

    A new pinned photodiode (PPD) CMOS image sensor with reverse biased p-type substrate has been developed and characterized. The sensor uses traditional PPDs with one additional deep implantation step to suppress the parasitic reverse currents, and can be fully depleted. The first prototypes have been manufactured on an 18 µm thick, 1000 Ω·cm epitaxial silicon wafers using 180 nm PPD image sensor process. Both front-side illuminated (FSI) and back-side illuminated (BSI) devices were manufactured in collaboration with Teledyne e2v. The characterization results from a number of arrays of 10 µm and 5.4 µm PPD pixels, with different shape, the size and the depth of the new implant are in good agreement with device simulations. The new pixels could be reverse-biased without parasitic leakage currents well beyond full depletion, and demonstrate nearly identical optical response to the reference non-modified pixels. The observed excessive charge sharing in some pixel variants is shown to not be a limiting factor in operation. This development promises to realize monolithic PPD CIS with large depleted thickness and correspondingly high quantum efficiency at near-infrared and soft X-ray wavelengths.

  12. A pin diode x-ray camera for laser fusion diagnostic imaging: Final technical report

    International Nuclear Information System (INIS)

    Jernigan, J.G.

    1987-01-01

    An x-ray camera has been constructed and tested for diagnostic imaging of laser fusion targets at the Laboratory for Laser Energetics (LLE) of the University of Rochester. The imaging detector, developed by the Hughes Aircraft Company, is a germanium PIN diode array of 10 x 64 separate elements which are bump bonded to a silicon readout chip containing a separate low noise amplifier for each pixel element. The camera assembly consists of a pinhole alignment mechanism, liquid nitrogen cryostat with detector mount and a thin beryllium entrance window, and a shielded rack containing the analog and digital electronics for operations. This x-ray camera has been tested on the OMEGA laser target chamber, the primary laser target facility of LLE, and operated via an Ethernet link to a SUN Microsystems workstation. X-ray images of laser targets are presented. The successful operation of this particular x-ray camera is a demonstration of the viability of the hybrid detector technology for future imaging and spectroscopic applications. This work was funded by the Department of Energy (DOE) as a project of the National Laser Users Facility (NLUF)

  13. Dependence of J c on pinning center morphology: An explanation of record J c observed for discontinuous columnar pinning of vortices

    International Nuclear Information System (INIS)

    Weinstein, R.; Gandini, A.; Parks, D.; Sawh, R.; Mayes, B.

    2006-01-01

    An experimental study of defects caused by ion irradiation has proven that very discontinuous multiple-in-line-damage results in much higher J c than continuous columnar pinning centers. This is contrary to conventional wisdom. We develop a first approximation to a theory relating J c to the morphology of pinning centers. Qualitative agreement with experiment is achieved. Conclusions indicate the relative importance of pinning potential, percolation, and critical temperature for various morphologies. Results suggest the leading importance of pinning, compared to texture, weak links and oxygenation in achievement of the goal of high J c especially in large grain HTS

  14. Periodically poled silicon

    Science.gov (United States)

    Hon, Nick K.; Tsia, Kevin K.; Solli, Daniel R.; Khurgin, Jacob B.; Jalali, Bahram

    2010-02-01

    Bulk centrosymmetric silicon lacks second-order optical nonlinearity χ(2) - a foundational component of nonlinear optics. Here, we propose a new class of photonic device which enables χ(2) as well as quasi-phase matching based on periodic stress fields in silicon - periodically-poled silicon (PePSi). This concept adds the periodic poling capability to silicon photonics, and allows the excellent crystal quality and advanced manufacturing capabilities of silicon to be harnessed for devices based on χ(2)) effects. The concept can also be simply achieved by having periodic arrangement of stressed thin films along a silicon waveguide. As an example of the utility, we present simulations showing that mid-wave infrared radiation can be efficiently generated through difference frequency generation from near-infrared with a conversion efficiency of 50% based on χ(2) values measurements for strained silicon reported in the literature [Jacobson et al. Nature 441, 199 (2006)]. The use of PePSi for frequency conversion can also be extended to terahertz generation. With integrated piezoelectric material, dynamically control of χ(2)nonlinearity in PePSi waveguide may also be achieved. The successful realization of PePSi based devices depends on the strength of the stress induced χ(2) in silicon. Presently, there exists a significant discrepancy in the literature between the theoretical and experimentally measured values. We present a simple theoretical model that produces result consistent with prior theoretical works and use this model to identify possible reasons for this discrepancy.

  15. Nonlinear silicon photonics

    Science.gov (United States)

    Tsia, Kevin K.; Jalali, Bahram

    2010-05-01

    An intriguing optical property of silicon is that it exhibits a large third-order optical nonlinearity, with orders-ofmagnitude larger than that of silica glass in the telecommunication band. This allows efficient nonlinear optical interaction at relatively low power levels in a small footprint. Indeed, we have witnessed a stunning progress in harnessing the Raman and Kerr effects in silicon as the mechanisms for enabling chip-scale optical amplification, lasing, and wavelength conversion - functions that until recently were perceived to be beyond the reach of silicon. With all the continuous efforts developing novel techniques, nonlinear silicon photonics is expected to be able to reach even beyond the prior achievements. Instead of providing a comprehensive overview of this field, this manuscript highlights a number of new branches of nonlinear silicon photonics, which have not been fully recognized in the past. In particular, they are two-photon photovoltaic effect, mid-wave infrared (MWIR) silicon photonics, broadband Raman effects, inverse Raman scattering, and periodically-poled silicon (PePSi). These novel effects and techniques could create a new paradigm for silicon photonics and extend its utility beyond the traditionally anticipated applications.

  16. Nonlinear silicon photonics

    Science.gov (United States)

    Borghi, M.; Castellan, C.; Signorini, S.; Trenti, A.; Pavesi, L.

    2017-09-01

    Silicon photonics is a technology based on fabricating integrated optical circuits by using the same paradigms as the dominant electronics industry. After twenty years of fervid development, silicon photonics is entering the market with low cost, high performance and mass-manufacturable optical devices. Until now, most silicon photonic devices have been based on linear optical effects, despite the many phenomenologies associated with nonlinear optics in both bulk materials and integrated waveguides. Silicon and silicon-based materials have strong optical nonlinearities which are enhanced in integrated devices by the small cross-section of the high-index contrast silicon waveguides or photonic crystals. Here the photons are made to strongly interact with the medium where they propagate. This is the central argument of nonlinear silicon photonics. It is the aim of this review to describe the state-of-the-art in the field. Starting from the basic nonlinearities in a silicon waveguide or in optical resonator geometries, many phenomena and applications are described—including frequency generation, frequency conversion, frequency-comb generation, supercontinuum generation, soliton formation, temporal imaging and time lensing, Raman lasing, and comb spectroscopy. Emerging quantum photonics applications, such as entangled photon sources, heralded single-photon sources and integrated quantum photonic circuits are also addressed at the end of this review.

  17. Silicon germanium mask for deep silicon etching

    KAUST Repository

    Serry, Mohamed

    2014-07-29

    Polycrystalline silicon germanium (SiGe) can offer excellent etch selectivity to silicon during cryogenic deep reactive ion etching in an SF.sub.6/O.sub.2 plasma. Etch selectivity of over 800:1 (Si:SiGe) may be achieved at etch temperatures from -80 degrees Celsius to -140 degrees Celsius. High aspect ratio structures with high resolution may be patterned into Si substrates using SiGe as a hard mask layer for construction of microelectromechanical systems (MEMS) devices and semiconductor devices.

  18. Silicon germanium mask for deep silicon etching

    KAUST Repository

    Serry, Mohamed; Rubin, Andrew; Refaat, Mohamed; Sedky, Sherif; Abdo, Mohammad

    2014-01-01

    Polycrystalline silicon germanium (SiGe) can offer excellent etch selectivity to silicon during cryogenic deep reactive ion etching in an SF.sub.6/O.sub.2 plasma. Etch selectivity of over 800:1 (Si:SiGe) may be achieved at etch temperatures from -80 degrees Celsius to -140 degrees Celsius. High aspect ratio structures with high resolution may be patterned into Si substrates using SiGe as a hard mask layer for construction of microelectromechanical systems (MEMS) devices and semiconductor devices.

  19. Clinical and histomorphometrical study on titanium dioxide-coated external fixation pins.

    Science.gov (United States)

    Koseki, Hironobu; Asahara, Tomohiko; Shida, Takayuki; Yoda, Itaru; Horiuchi, Hidehiko; Baba, Koumei; Osaki, Makoto

    2013-01-01

    Pin site infection is the most common and significant complication of external fixation. In this work, the efficacy of pins coated with titanium dioxide (TiO(2)) for inhibition of infection was compared with that of stainless steel control pins in an in vivo study. Pins contaminated with an identifiable Staphylococcus aureus strain were inserted into femoral bone in a rat model and exposed to ultraviolet A light for 30 minutes. On day 14, the animals were sacrificed and the bone and soft tissue around the pin were retrieved. The clinical findings and histological findings were evaluated in 60 samples. Clinical signs of infection were present in 76.7% of untreated pins, but in only 36.7% of TiO(2)-coated pins. The histological bone infection score and planimetric rate of occupation for bacterial colonies and neutrophils in the TiO(2)-coated pin group were lower than those in the control group. The bone-implant contact ratio of the TiO(2)-coated pin group was significantly higher (71.4%) than in the control pin group (58.2%). The TiO(2) was successful in decreasing infection both clinically and histomorphometrically. The photocatalytic bactericidal effect of TiO(2) is thought to be useful for inhibiting pin site infection after external fixation.

  20. Wear-Induced Changes in FSW Tool Pin Profile: Effect of Process Parameters

    Science.gov (United States)

    Sahlot, Pankaj; Jha, Kaushal; Dey, G. K.; Arora, Amit

    2018-06-01

    Friction stir welding (FSW) of high melting point metallic (HMPM) materials has limited application due to tool wear and relatively short tool life. Tool wear changes the profile of the tool pin and adversely affects weld properties. A quantitative understanding of tool wear and tool pin profile is crucial to develop the process for joining of HMPM materials. Here we present a quantitative wear study of H13 steel tool pin profile for FSW of CuCrZr alloy. The tool pin profile is analyzed at multiple traverse distances for welding with various tool rotational and traverse speeds. The results indicate that measured wear depth is small near the pin root and significantly increases towards the tip. Near the pin tip, wear depth increases with increase in tool rotational speed. However, change in wear depth near the pin root is minimal. Wear depth also increases with decrease in tool traverse speeds. Tool pin wear from the bottom results in pin length reduction, which is greater for higher tool rotational speeds, and longer traverse distances. The pin profile changes due to wear and result in root defect for long traverse distance. This quantitative understanding of tool wear would be helpful to estimate tool wear, optimize process parameters, and tool pin shape during FSW of HMPM materials.

  1. Performance of refractory alloy-clad fuel pins

    International Nuclear Information System (INIS)

    Dutt, D.S.; Cox, C.M.; Millhollen, M.K.

    1984-12-01

    This paper discusses objectives and basic design of two fuel-cladding tests being conducted in support of SP-100 technology development. Two of the current space nuclear power concepts use conventional pin type designs, where a coolant removes the heat from the core and transports it to an out-of-core energy conversion system. An extensive irradiation testing program was conducted in the 1950's and 1960's to develop fuel pins for space nuclear reactors. The program emphasized refractory metal clad uranium nitride (UN), uranium carbide (UC), uranium oxide (UO 2 ), and metal matrix fuels (UCZr and BeO-UO 2 ). Based on this earlier work, studies presented here show that UN and UO 2 fuels in conjunction with several refractory metal cladding materials demonstrated high potential for meeting space reactor requirements and that UC could serve as an alternative but higher risk fuel

  2. Flux-pinning-induced stress and magnetostriction in bulk superconductors

    International Nuclear Information System (INIS)

    Johansen, Tom H.

    2000-01-01

    The development of bulk high-temperature superconductors (HTSs) and their applications has today come to a point where the mechanical response to high magnetic fields may be more important than their critical-current density and large-grain property. Reviewed in this article are the recent studies of the magneto-elastic effects which are caused by flux pinning in the superconductors. This includes the work on the giant irreversible magnetostriction and internal stress, which often cause fatal cracking of the HTS bulks as they become magnetized. The cracking is a problem that today accompanies the quest for the highest trapped field values, and the latest development in this area is also presented. While the first part is an overview of experimental efforts, the second summarizes the work done to model the pinning-induced stress and strain under various magnetic and geometrical conditions. (author)

  3. Superconducting pinning in BCC niobium-base alloys

    International Nuclear Information System (INIS)

    Hu, S.

    1981-01-01

    The structure dependence of critical current density J/sub c/ in superconducting alloys Nb--Zr and Nb--Ti was studied by means of x-ray analysis and tensile test. Experimental results indicate that, in the absence of second phase particles, annealing increases J/sub c/ in deformed alloys due to rearrangement of dislocations into cell structure and the cell walls are effective pinning centers for magnetic flux. In the precipitation process of second phase particles, new dislocations are formed due to the relaxation of coherent stress field. These new dislocations increases the dislocation density and the flux pinning ability of the cell walls, which in turn lead to a further increase of J/sub c/. The mechanism that causes precipitates to increase the current-carrying ability in Nb--Zr and Nb--Ti alloys is therefore the same as that of cold-work deformation

  4. Single absorbable polydioxanone pin fixation for distal chevron bunion osteotomies.

    Science.gov (United States)

    Deorio, J K; Ware, A W

    2001-10-01

    The distal chevron osteotomy is a well-established technique for correction of symptomatic mild to moderate metatarsus primus varus with hallux valgus deformity. Fixation of the osteotomy ranges from none to bone pegs, Kirschner wires, screws, or absorbable pins. We evaluated one surgeon's (J.K.D.) results of distal chevron osteotomy fixation with a single, nonpredrilled, 1.3-mm poly-p-dioxanone pin and analyzed any differences in patients with unilateral or bilateral symptomatic metatarsus primus varus with hallux valgus deformities. All osteotomies healed without evidence of infection, osteolysis, nonunion, or necrosis. Equal correction was achieved in unilateral and bilateral procedures. The technique is quick and easy, and adequate fixation is achieved.

  5. Magnetization pinning in conducting films demonstrated using broadband ferromagnetic resonance

    Science.gov (United States)

    Kostylev, M.; Stashkevich, A. A.; Adeyeye, A. O.; Shakespeare, C.; Kostylev, N.; Ross, N.; Kennewell, K.; Magaraggia, R.; Roussigné, Y.; Stamps, R. L.

    2010-11-01

    The broadband microstrip ferromagnetic resonance (FMR), cavity FMR, and Brillouin light scattering spectroscopy techniques have been applied for detection and characterization of a magnetic inhomogeneity in a film sample. In the case of a 100 nm thick permalloy film, an additional magnetically depleted top sublayer has been detected due to pinning effect it produces on the magnetization in the bulk of the film. The pinning results in appearance of an exchange standing spin wave mode in the broadband FMR absorption spectrum, whose amplitudes are different depending on whether the film or the film substrate faces the microstrip transducer. Comparison of the experimental amplitudes for this mode with results of our theory for both film placements revealed that the depleted layer is located at the film surface facing away from the film substrate. Subsequent broadband FMR characterization of a large number of other presumably single-layer films with thicknesses in the range 30-100 nm showed the same result.

  6. Leituras semióticas de Pinóquio

    Directory of Open Access Journals (Sweden)

    Rafael Giardini Lenzi

    2013-12-01

    Full Text Available Esta resenha faz breve exposição do conteúdo de Pinocchio: nuove avventure tra segni e linguaggi, organizado por Paolo Fabbri e Isabella Pezzini, que apresenta dez artigos e um tautograma que tratam do tema Pinóquio, alternando entre elementos do texto original, elementos presentes em variações do romance e abordagens sobre a tradução ou a variação em si, sob a óptica da semiótica discursiva. A perseverança e forte proliferação do tema Pinóquio, originalmente ou sob outros pontos de vista trazidos pelos meios de comunicação, estabelece o texto como uma fábula da atualidade que sempre atraiu o olhar científico.

  7. Intrinsic pinning in superconductors with extremely small coherence lengths

    International Nuclear Information System (INIS)

    Schimmele, L.; Kronmueller, H.; Teichler, H.

    1988-01-01

    By means of a Ginsburg-Landau-type theory which takes into account the discrete lattice structure the variation of the energy ('Peierls potential') of an isolated flux line is calculated when shifted relatively to the crystal lattice. In particular, a primitive cubic lattice is considered with a straight flux line, aligned parallel to a cubic axis. The resulting Peierls potential may lead to intrinsic pinning if the coherence length is smaller than about two nearest neighbour distances. The coherence lengths at low temperatures determined for the recently discovered high T c superconductors of the YBa 2 Cu 3 O 7 class come very close to this value so that intrinsic pinning might possibly be relevant for these superconductors. (author)

  8. Polarization of concave domains by traveling wave pinning.

    Directory of Open Access Journals (Sweden)

    Slawomir Bialecki

    Full Text Available Pattern formation is one of the most fundamental yet puzzling phenomena in physics and biology. We propose that traveling front pinning into concave portions of the boundary of 3-dimensional domains can serve as a generic gradient-maintaining mechanism. Such a mechanism of domain polarization arises even for scalar bistable reaction-diffusion equations, and, depending on geometry, a number of stationary fronts may be formed leading to complex spatial patterns. The main advantage of the pinning mechanism, with respect to the Turing bifurcation, is that it allows for maintaining gradients in the specific regions of the domain. By linking the instant domain shape with the spatial pattern, the mechanism can be responsible for cellular polarization and differentiation.

  9. Design and Operation of 3-Pin FTL HVAC System

    International Nuclear Information System (INIS)

    Chi, D. Y.; Sim, B. S.; Park, S. K.; Park, K. N.; Lee, J. M.; Ahn, S. H.; Lee, C. Y.; Kim, Y. J.

    2005-01-01

    According to the increasing demand for irradiation tests to develop new fuels, the 3-Pin FTL(Fuel Test Loop for 3 pin test fuel) facility has now been under design to conduct in-core fuel performance tests at the operating conditions, which will be installed at HANARO. The HVAC system of the FTL will be dependent on that of the HANARO. The FTL has three equipments rooms, which are the room 1, room 2 and the control room. The high pressure and high temperature equipments will be installed in the room 1. The atmosphere of the room 1 shall be maintained under the designed condition. This paper describes the design of the FTL HVAC system in the room 1

  10. Exponential synchronization of complex delayed dynamical networks via pinning periodically intermittent control

    Energy Technology Data Exchange (ETDEWEB)

    Cai Shuiming, E-mail: caishuiming2008@yahoo.com.c [Department of Mathematics, Shanghai University, Shanghai 200444 (China); Institute of System Biology, Shanghai University, Shanghai 200444 (China); Hao Junjun [Institute of System Biology, Shanghai University, Shanghai 200444 (China); He, Qinbin [Department of Mathematics, Taizhou University, Linhai 317000 (China); Institute of System Biology, Shanghai University, Shanghai 200444 (China); Liu Zengrong, E-mail: zrongliu@126.co [Department of Mathematics, Shanghai University, Shanghai 200444 (China) and Institute of System Biology, Shanghai University, Shanghai 200444 (China)

    2011-05-09

    The problem of synchronization for a class of complex delayed dynamical networks via pinning periodically intermittent control is considered in this Letter. Some novel and useful exponential synchronization criteria are obtained by utilizing the methods which are different from the techniques employed in the existing works, and the derived results are less conservative. Especially, the traditional assumptions on control width and time delays are released in our results. Moreover, a pinning scheme deciding what nodes should be chosen as pinned candidates and how many nodes are needed to be pinned for a fixed coupling strength is provided. A Barabasi-Albert network example is finally given to illustrate the effectiveness of the theoretical results. - Highlights: Pinning control problem of complex networks via intermittent control is investigated. The traditional assumptions on control width and time delays are removed. A scheme deciding what nodes should be chosen as pinned candidates is proposed. A scheme deciding how many nodes are needed to be pinned is provided.

  11. Evaluation of PWR and BWR pin cell benchmark results

    Energy Technology Data Exchange (ETDEWEB)

    Pilgroms, B.J.; Gruppelaar, H.; Janssen, A.J. (Netherlands Energy Research Foundation (ECN), Petten (Netherlands)); Hoogenboom, J.E.; Leege, P.F.A. de (Interuniversitair Reactor Inst., Delft (Netherlands)); Voet, J. van der (Gemeenschappelijke Kernenergiecentrale Nederland NV, Dodewaard (Netherlands)); Verhagen, F.C.M. (Keuring van Electrotechnische Materialen NV, Arnhem (Netherlands))

    1991-12-01

    Benchmark results of the Dutch PINK working group on the PWR and BWR pin cell calculational benchmark as defined by EPRI are presented and evaluated. The observed discrepancies are problem dependent: a part of the results is satisfactory, some other results require further analysis. A brief overview is given of the different code packages used in this analysis. (author). 14 refs.; 9 figs.; 30 tabs.

  12. Axial migratin of cesium in LMFBR fuel pins

    International Nuclear Information System (INIS)

    Karnesky, R.A.; Bridges, A.E.; Jost, J.W.

    1981-11-01

    A correlated model for quantitatively predicting the behavior of cesium in LMFBR fuel pins has been developed. This correlation was shown to be in good agreement with experimental data. It has been used to predict the behavior of cesium in the FFTF driver fuel and as the result of this analysis it has been shown that the accumulation of cesium in the insulator pellets at the ends of the fuel column will not be life limiting

  13. Anticipating WPS PIN Vulnerability to Secure Wireless Network

    Directory of Open Access Journals (Sweden)

    Indra Dwi Rianto

    2013-12-01

    Full Text Available WiFi Protected Setup (WPS is a standardized function supported by numerous vendors of wireless routers and access point to help set up connection to a wireless local area network. It is designed to simplify the set up and generally enabled by default. Due to design flaw, the WPS or QSS PIN is susceptible to a brute forceattack. In this paper, we test the security vulnerability occurred, evaluate the performance and give recommendations to anticipate the attack.

  14. X-ray measurement with Pin type semiconductor detectors

    International Nuclear Information System (INIS)

    Ramirez J, F.J.

    1999-01-01

    Here are presented the experimental results of the applications of Pin type radiation detectors developed in a National Institute of Nuclear Research (ININ) project, in the measurement of low energy gamma and X-rays. The applications were oriented mainly toward the Medical Physics area. It is planned other applications which are in process of implementation inside the National Institute of Nuclear Research in Mexico. (Author)

  15. Pinning by oxygen vacancies in high-Tc superconductors

    International Nuclear Information System (INIS)

    Chudnovsky, E.M.

    1990-01-01

    It is shown that recent data of Murray et al. on spatial correlations in flux lattices of Bi-Sr-Ca-Cu-O (BSCCO) may be explained if one assumes that 1% of oxygen atoms in CuO 2 layers are missing. This estimate, being in remarkable agreement with that deduced by Kes and van der Beek from ac-susceptibility measurements, provides strong confidence that oxygen vacancies are the major source of pinning in BSCCO

  16. Pins and posters: paradigms for content publication on situated displays

    OpenAIRE

    José, Rui; Pinto, Helder; Siva, Bruno; Melro, Ana

    2013-01-01

    Public display systems are still far from being a communication medium that people can appropriate to serve diverse communication goals. Moving towards open displays will require new publication paradigms that can overcome the challenges of meaningful engagement and enable users to fully understand and control the entire publication process. In this paper, we report on the study of two novel and complimentary communication paradigms for public displays inspired by the metaphors of pin badges ...

  17. Prevention of pin tract infection with titanium-copper alloys.

    Science.gov (United States)

    Shirai, Toshiharu; Tsuchiya, Hiroyuki; Shimizu, Tohru; Ohtani, Kaori; Zen, Yo; Tomita, Katsuro

    2009-10-01

    The most frequent complication in external fixation is pin tract infection. To reduce the incidence of implant-associated infection, many published reports have looked at preventing bacterial adhesion by treating the pin surface. This study aimed to evaluate the antibacterial activity of a Titanium-Copper (Ti-Cu) alloy on implant infection, and to determine the potential use of the Ti-Cu alloy as a biomaterial. Two forms of Ti-Cu alloys were synthesized: one with 1% Cu and the other with 5% Cu. For analyzing infectious behavior, the implants were exposed to Staphylococcus aureus and Escherichia coli. The reaction of pathogens to the Ti-Cu alloys was compared with their reaction to stainless steel and pure titanium as controls. Both Ti-Cu alloys evidently inhibited colonization by both bacteria. Conversely, cytocompatibility studies were performed using fibroblasts and colony formation on the metals was assessed by counting the number of colonies. Ti-1% Cu alloy showed no difference in the number of colonies compared with the control. External fixator pins made of Ti-Cu alloys were evaluated in a rabbit model. The tissue-implant interactions were analyzed for the presence of infection, inflammatory changes and osteoid-formation. Ti-1% Cu alloy significantly inhibited inflammation and infection, and had excellent osteoid-formation. Copper blood levels were measured before surgery and at 14 days postoperatively. Preoperative and postoperative blood copper values were not statistically different. Overall, it was concluded that Ti-Cu alloys have antimicrobial activity and substantially reduce the incidence of pin tract infection. Ti-1% Cu alloy shows particular promise as a biomaterial. (c) 2009 Wiley Periodicals, Inc.

  18. Effective temperature in driven vortex lattices with random pinning

    International Nuclear Information System (INIS)

    Kolton, Alejandro B.; Dominguez, Daniel; Exartier, Raphael; Cugliandolo, Leticia F.; Groenbech-Jensen, N.

    2003-09-01

    We study numerically correlation and response functions in non-equilibrium driven vortex lattices with random pinning. From a generalized fluctuation-dissipation relation we calculate an effective transverse temperature in the fluid moving phase. We find that the effective temperature decreases with increasing driving force and becomes equal to the equilibrium melting temperature when the dynamic transverse freezing occurs. We also discuss how the effective temperature can be measured experimentally from a generalized Kubo formula. (author)

  19. FFTF metal fuel pin sodium bond quality verification

    International Nuclear Information System (INIS)

    Pitner, A.L.; Dittmer, J.O.

    1988-12-01

    The Fast Flux Test Facility (FFTF) Series III driver fuel design consists of U-10Zr fuel slugs contained in a ferritic alloy cladding. A liquid metal, sodium bond between the fuel and cladding is required to prevent unacceptable temperatures during operation. Excessive voiding or porosity in the sodium thermal bond could result in localized fuel melting during irradiation. It is therefore imperative that bond quality be verified during fabrication of these metal fuel pins prior to irradiation. This document discusses this verification

  20. Properties of films and p-i-n photo-transformed structures on the basis of a-Si:H and its alloys, received in glow discharge of a constant current

    International Nuclear Information System (INIS)

    Tauasarov, K.

    1997-01-01

    The work devoted to investigation and control of structural, optical and photoelectric properties of films of amorphous hydrogenated silicon and its alloys, deposited in glow discharge of a constant current were done, creation of photo transformed p-i-n structures investigation its photoelectric characteristics. The main results and conclusions: A new method of deposition in glow discharge of a constant current qualitative doping and un doping a-Si:H layer and p-i-n structures on the basis of amorphous hydrogenated silicon was developed. For reception of amorphous p + and n - films for first time synthesised and applied mono-silborina and mono-silphosfin, containing pointed Si-B and Si-P linkages. New layered linear - organized structure in the films a-Si:H (T=200 deg C) was found out with distance between layers 7,5 A-o. Degree of crystallinity from combinational spectrum was determined. Concentration of films and connection between a hydrogen and silicon was determined from a IR-spectrum. It was shown that introduction of vary zone p + layer from a-Si x C 1-x :H into photo transformed p-i-n structure on the basis of a-Si:H results to decreasing of recombination losses in the area of p-i hetero boundary, and as result a photosensitive in the short-wave area of a spectrum increased. Best p-i-n structures in condition of natural illumination had following parameters: density of current of short circuit I sc =12,9 m A/cm 2 , voltage in single course U lm =0,85 V, factor of Ff.=0,55 filling and h=7% efficiency. (author)

  1. The dynamics of plant plasma membrane proteins: PINs and beyond.

    Science.gov (United States)

    Luschnig, Christian; Vert, Grégory

    2014-08-01

    Plants are permanently situated in a fixed location and thus are well adapted to sense and respond to environmental stimuli and developmental cues. At the cellular level, several of these responses require delicate adjustments that affect the activity and steady-state levels of plasma membrane proteins. These adjustments involve both vesicular transport to the plasma membrane and protein internalization via endocytic sorting. A substantial part of our current knowledge of plant plasma membrane protein sorting is based on studies of PIN-FORMED (PIN) auxin transport proteins, which are found at distinct plasma membrane domains and have been implicated in directional efflux of the plant hormone auxin. Here, we discuss the mechanisms involved in establishing such polar protein distributions, focusing on PINs and other key plant plasma membrane proteins, and we highlight the pathways that allow for dynamic adjustments in protein distribution and turnover, which together constitute a versatile framework that underlies the remarkable capabilities of plants to adjust growth and development in their ever-changing environment. © 2014. Published by The Company of Biologists Ltd.

  2. Optimization of geometric parameters of heat exchange pipes pin finning

    Science.gov (United States)

    Akulov, K. A.; Golik, V. V.; Voronin, K. S.; Zakirzakov, A. G.

    2018-05-01

    The work is devoted to optimization of geometric parameters of the pin finning of heat-exchanging pipes. Pin fins were considered from the point of view of mechanics of a deformed solid body as overhang beams with a uniformly distributed load. It was found out under what geometric parameters of the nib (diameter and length); the stresses in it from the influence of the washer fluid will not exceed the yield strength of the material (aluminum). Optimal values of the geometric parameters of nibs were obtained for different velocities of the medium washed by them. As a flow medium, water and air were chosen, and the cross section of the nibs was round and square. Pin finning turned out to be more than 3 times more compact than circumferential finning, so its use makes it possible to increase the number of fins per meter of the heat-exchanging pipe. And it is well-known that this is the main method for increasing the heat transfer of a convective surface, giving them an indisputable advantage.

  3. Contact and Non-contact Measurements of Grinding Pins

    Directory of Open Access Journals (Sweden)

    Magdziak Marek

    2015-01-01

    Full Text Available The paper presents the results of contact and non-contact measurements of external profiles of selected grinding pins. The measurements were conducted in order to choose the appropriate measuring technique in the case of the considered measurement task. In the case of contact measurements the coordinate measuring machine ACCURA II was applied. The used coordinate measuring machine was equipped with the contact scanning probe VAST XT and the Calypso inspection software. Contact coordinate measurements were performed by using of different measurement strategies. The applied strategies included different scanning velocities and distances between measured points. Non-contact measurements were conducted by means of the tool presetter produced by the Mahr company. On the basis of gained results the guidelines concerning measurements of grinding pins were formulated. The measurements of analyzed grinding pins performed by means of the non-contact measuring system are characterized by higher reproducibility than the contact measurements. The low reproducibility of contact measurements may be connected with the inaccuracy of the selected coordinate measuring machine and the measuring probe, the measurement parameters and environmental conditions in the laboratory where the coordinate measuring machine is located. Moreover, the paper presents the possible application of results of conducted investigations. The results of non-contact measurements can be used in the simulation studies of grinding processes. The simulations may reduce the costs of machining processes.

  4. End-threaded intramedullary positive profile screw ended self-tapping pin (Admit pin) - A cost-effective novel implant for fixing canine long bone fractures.

    Science.gov (United States)

    Chanana, Mitin; Kumar, Adarsh; Tyagi, Som Prakash; Singla, Amit Kumar; Sharma, Arvind; Farooq, Uiase Bin

    2018-02-01

    The current study was undertaken to evaluate the clinical efficacy of end-threaded intramedullary pinning for management of various long bone fractures in canines. This study was conducted in two phases, managing 25 client-owned dogs presented with different fractures. The technique of application of end-threaded intramedullary pinning in long bone fractures was initially standardized in 6 clinical patients presented with long bone fractures. In this phase, end-threaded pins of different profiles, i.e., positive and negative, were used as the internal fixation technique. On the basis of results obtained from standardization phase, 19 client-owned dogs clinically presented with different fractures were implanted with end-threaded intramedullary positive profile screw ended self-tapping pin in the clinical application phase. The patients, allocated randomly in two groups, when evaluated postoperatively revealed slight pin migration in Group-I (negative profile), which resulted in disruption of callus site causing delayed union in one case and large callus formation in other two cases whereas no pin migration was observed in Group-II (positive profile). Other observations in Group-I was reduced muscle girth and delayed healing time as compared to Group-II. In clinical application, phase 21 st and 42 nd day post-operative radiographic follow-up revealed no pin migration in any of the cases, and there was no bone shortening or fragment collapse in end-threaded intramedullary positive profile screw ended self-tapping pin. The end-threaded intramedullary positive profile screw ended self-tapping pin used for fixation of long bone fractures in canines can resist pin migration, pin breakage, and all loads acting on the bone, i.e., compression, tension, bending, rotation, and shearing to an extent with no post-operative complications.

  5. Pin-wise Reactor Analysis Based on the Generalized Equivalence Theory

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hwan Yeal; Heo, Woong; Kim, Yong Hee [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    In this paper, a pin-wise reactor analysis is performed based on the generalized equivalence theory. From the conventional fuel assembly lattice calculations, pin-wise 2-group cross sections and pin DFs are generated. Based on the numerical results on a small PWR benchmark, it is observed that the pin-wise core analysis provide quite accurate prediction on the effective multiplication factor and the peak pin power error is bounded by about 3% in peripheral fuel assemblies facing the baffle-reflector. Also, it was found that relatively large pin power errors occur along the interface between clearly different fuel assemblies. It is expected that the GET-based pin-by-pin core calculation can be further developed as an advanced method for reactor analysis via improving the group constants and discontinuity factors. Recently, high-fidelity multi-dimensional analysis tools are gaining more attention because of their accurate prediction of local parameters for core design and safety assessment. In terms of accuracy, direct whole-core transport is quite promising. However, it is clear that it is still very costly in terms of the computing time and memory requirements. Another possible solution is the pin-by-pin core analysis in which only small fuel pins are homogenized and the 3-D core analysis is still performed using a low-order operator such as the diffusion theory. In this paper, a pin-by-pin core analysis is performed using the hybrid CMFD (HCMFD) method. Hybrid CMFD is a new global-local iteration method that has been developed for efficient parallel calculation of pinby-pin heterogeneous core analysis. For the HCMFD method, the one-node CMFD scheme is combined with a local two-node CMFD method in a non-linear way. Since the SPH method is iterative and SPH factors are not direction dependent, it is clear that SPH method takes more computing cost and cannot take into account the different heterogeneity and transport effects at each pin interface. Unlike the SPH

  6. Interaction of Light with Metallized Ultrathin Silicon Membrane

    Science.gov (United States)

    Shome, Krishanu

    Freestanding metallized structures, a few tens of nanometer thick, show promise in creating flow-through sensors, single molecule detectors and novel solar cells. In this thesis we study test structures that are a step towards creating such devices. Finite- difference time-domain simulations have been used to understand and predict the interaction of light with such devices. Porous nanocrystalline silicon membrane is a novel freestanding layer structure that has been used as a platform to fabricate and study sensors and novel slot nanohole devices. Optical mode studies of the sensing structures, together with the method of fabrication inspired the creation of ultrathin freestanding hydrogenated amorphous silicon p-i-n junctions solar cells. All the freestanding structures used in this thesis are just a few tens of nanometers in thicknesses. In the first part of the thesis the sensing properties of the metallized porous nanocrystalline structure are studied. The surprising blueshift associated with the sensing peak is observed experimentally and predicted theoretically with the help of simulations. Polarization dependence of the membranes is predicted and confirmed for angled deposition of metal on the membranes. In the next part, a novel slot structure is fabricated and modeled to study the slot effect in nanohole metal-insulator-metal structures. Atomic layer deposition of alumina is used to conformally deposit alumina within the nanohole to create the slot structure. Simulation models were used to calculate the lowest modal volume of 4x10-5 mum3 for an optimized structure. In the last part of the thesis, freestanding solar cells are fabricated by effectively replacing the porous nanocrystalline silicon layer of the membranes with a hydrogenated amorphous silicon p-i-n junction with metal layers on both sides of the p-i-n junction. The metal layers act both as electrical contacts as well as mirrors for a Fabry Perot cavity resonator. This helps in tuning the

  7. Process for making silicon

    Science.gov (United States)

    Levin, Harry (Inventor)

    1987-01-01

    A reactor apparatus (10) adapted for continuously producing molten, solar grade purity elemental silicon by thermal reaction of a suitable precursor gas, such as silane (SiH.sub.4), is disclosed. The reactor apparatus (10) includes an elongated reactor body (32) having graphite or carbon walls which are heated to a temperature exceeding the melting temperature of silicon. The precursor gas enters the reactor body (32) through an efficiently cooled inlet tube assembly (22) and a relatively thin carbon or graphite septum (44). The septum (44), being in contact on one side with the cooled inlet (22) and the heated interior of the reactor (32) on the other side, provides a sharp temperature gradient for the precursor gas entering the reactor (32) and renders the operation of the inlet tube assembly (22) substantially free of clogging. The precursor gas flows in the reactor (32) in a substantially smooth, substantially axial manner. Liquid silicon formed in the initial stages of the thermal reaction reacts with the graphite or carbon walls to provide a silicon carbide coating on the walls. The silicon carbide coated reactor is highly adapted for prolonged use for production of highly pure solar grade silicon. Liquid silicon (20) produced in the reactor apparatus (10) may be used directly in a Czochralski or other crystal shaping equipment.

  8. Hydrogen in amorphous silicon

    International Nuclear Information System (INIS)

    Peercy, P.S.

    1980-01-01

    The structural aspects of amorphous silicon and the role of hydrogen in this structure are reviewed with emphasis on ion implantation studies. In amorphous silicon produced by Si ion implantation of crystalline silicon, the material reconstructs into a metastable amorphous structure which has optical and electrical properties qualitatively similar to the corresponding properties in high-purity evaporated amorphous silicon. Hydrogen studies further indicate that these structures will accomodate less than or equal to 5 at.% hydrogen and this hydrogen is bonded predominantly in a monohydride (SiH 1 ) site. Larger hydrogen concentrations than this can be achieved under certain conditions, but the excess hydrogen may be attributed to defects and voids in the material. Similarly, glow discharge or sputter deposited amorphous silicon has more desirable electrical and optical properties when the material is prepared with low hydrogen concentration and monohydride bonding. Results of structural studies and hydrogen incorporation in amorphous silicon were discussed relative to the different models proposed for amorphous silicon

  9. Transformational silicon electronics

    KAUST Repository

    Rojas, Jhonathan Prieto

    2014-02-25

    In today\\'s traditional electronics such as in computers or in mobile phones, billions of high-performance, ultra-low-power devices are neatly integrated in extremely compact areas on rigid and brittle but low-cost bulk monocrystalline silicon (100) wafers. Ninety percent of global electronics are made up of silicon. Therefore, we have developed a generic low-cost regenerative batch fabrication process to transform such wafers full of devices into thin (5 μm), mechanically flexible, optically semitransparent silicon fabric with devices, then recycling the remaining wafer to generate multiple silicon fabric with chips and devices, ensuring low-cost and optimal utilization of the whole substrate. We show monocrystalline, amorphous, and polycrystalline silicon and silicon dioxide fabric, all from low-cost bulk silicon (100) wafers with the semiconductor industry\\'s most advanced high-κ/metal gate stack based high-performance, ultra-low-power capacitors, field effect transistors, energy harvesters, and storage to emphasize the effectiveness and versatility of this process to transform traditional electronics into flexible and semitransparent ones for multipurpose applications. © 2014 American Chemical Society.

  10. Test-beam evaluation of heavily irradiated silicon strip modules for ATLAS Phase-II Strip Tracker Upgrade

    CERN Document Server

    Blue, Andrew; The ATLAS collaboration

    2018-01-01

    The planned HL-LHC (High Luminosity LHC) is being designed to maximise the physics potential of the LHC with 10 years of operation at instantaneous luminosities of 7.5x1034cm−2s−1. A consequence of this increased luminosity is the expected radiation damage requiring the tracking detectors to withstand hadron equivalences to over 1x1015 1 MeV neutron equivalent per cm2 in the ATLAS Strips system. The silicon strip tracker exploits the concept of modularity. Fast readout electronics, deploying 130nm CMOS front-end electronics are glued on top of a silicon sensor to make a module. The radiation hard n-in-p micro-strip sensors used have been developed by the ATLAS ITk Strip Sensor collaboration and produced by Hamamatsu Photonics. A series of tests were performed at the DESY-II and CERN SPS test beam facilities to investigate the detailed performance of a strip module with both 2.5cm and 5cm length strips before and after irradiation with 8x1014neqcm−2 protons and a total ionising dose of 37.2MRad. The DURA...

  11. HLM fuel pin bundle experiments in the CIRCE pool facility

    Energy Technology Data Exchange (ETDEWEB)

    Martelli, Daniele, E-mail: daniele.martelli@ing.unipi.it [University of Pisa, Department of Civil and Industrial Engineering, Pisa (Italy); Forgione, Nicola [University of Pisa, Department of Civil and Industrial Engineering, Pisa (Italy); Di Piazza, Ivan; Tarantino, Mariano [Italian National Agency for New Technologies, Energy and Sustainable Economic Development, C.R. ENEA Brasimone (Italy)

    2015-10-15

    Highlights: • The experimental results represent the first set of values for LBE pool facility. • Heat transfer is investigated for a 37-pin electrical bundle cooled by LBE. • Experimental data are presented together with a detailed error analysis. • Nu is computed as a function of the Pe and compared with correlations. • Experimental Nu is about 25% lower than Nu derived from correlations. - Abstract: Since Lead-cooled Fast Reactors (LFR) have been conceptualized in the frame of GEN IV International Forum (GIF), great interest has focused on the development and testing of new technologies related to HLM nuclear reactors. In this frame the Integral Circulation Experiment (ICE) test section has been installed into the CIRCE pool facility and suitable experiments have been carried out aiming to fully investigate the heat transfer phenomena in grid spaced fuel pin bundles providing experimental data in support of European fast reactor development. In particular, the fuel pin bundle simulator (FPS) cooled by lead bismuth eutectic (LBE), has been conceived with a thermal power of about 1 MW and a uniform linear power up to 25 kW/m, relevant values for a LFR. It consists of 37 fuel pins (electrically simulated) placed on a hexagonal lattice with a pitch to diameter ratio of 1.8. The FPS was deeply instrumented by several thermocouples. In particular, two sections of the FPS were instrumented in order to evaluate the heat transfer coefficient along the bundle as well as the cladding temperature in different ranks of sub-channels. Nusselt number in the central sub-channel was therefore calculated as a function of the Peclet number and the obtained results were compared to Nusselt numbers obtained from convective heat transfer correlations available in literature on Heavy Liquid Metals (HLM). Results reported in the present work, represent the first set of experimental data concerning fuel pin bundle behaviour in a heavy liquid metal pool, both in forced and

  12. Vortex dynamics in supraconductors in the presence of anisotropic pinning

    International Nuclear Information System (INIS)

    Soroka, O.K.

    2004-01-01

    Vortex dynamics in two different classes of superconductors with anisotropic unidirected pinning sites was experimentally investigated by magnetoresistivity measurements: YBCO-films with unidirected twins and Nb-films deposited on faceted Al 2 O 3 substrate surfaces. For the interpretation of the experimental results a theoretical model based on the Fokker-Planck equation was used. It was proved by X-ray measurements that YBCO films prepared on (001) NdGaO 3 substrates exhibit only one twin orientation in contrast to YBCO films grown on (100) SrTiO 3 substrates. The magnetoresistivity measurements of the YBCO films with unidirected twin boundaries revealed the existence of two new magnetoresistivity components, which is a characteristic feature of a guided vortex motion: an odd longitudinal component with respect to the magnetic field sign reversal and an even transversal component. However, due to the small coherence length in YBCO and the higher density of point-like defects comparing to high-quality YBCO single crystals, the strength of the isotropic point pinning was comparable with the strength of the pinning produced by twins. This smeared out all e ects caused by the pinning anisotropy. The behaviour of the odd longitudinal component was found to be independent of the transport current direction with respect to the twin planes. The magnetoresistivity measurements of faceted Nb films demonstrated the appearance of an odd longitudinal and even transversal component of the magnetoresistivity. The temperature and magnetic field dependences of all relevant magnetoresistivity components were measured. The angles between the average vortex velocity vector and the transport current direction calculated from the experimental data for the different transport current orientations with respect to the facet ridges showed that the vortices moved indeed along the facet ridges. An anomalous Hall effect, i.e. a sign change of the odd transversal magnetoresistivity, has been

  13. Three-dimensional atomic mapping of hydrogenated polymorphous silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wanghua, E-mail: wanghua.chen@polytechnique.edu; Roca i Cabarrocas, Pere [LPICM, CNRS, Ecole Polytechnique, Université Paris-Saclay, 91128 Palaiseau (France); Pareige, Philippe [GPM, CNRS, Université et INSA de Rouen, Normandie Université, 76801 Saint Etienne du Rouvray (France)

    2016-06-20

    Hydrogenated polymorphous silicon (pm-Si:H) is a nanostructured material consisting of silicon nanocrystals embedded in an amorphous silicon matrix. Its use as the intrinsic layer in thin film p-i-n solar cells has led to good cell properties in terms of stability and efficiency. Here, we have been able to assess directly the concentration and distribution of nanocrystals and impurities (dopants) in p-i-n solar cells, by using femtosecond laser-assisted atom probe tomography (APT). An effective sample preparation method for APT characterization is developed. Based on the difference in atomic density between hydrogenated amorphous and crystalline silicon, we are able to distinguish the nanocrystals from the amorphous matrix by using APT. Moreover, thanks to the three-dimensional reconstruction, we demonstrate that Si nanocrystals are homogeneously distributed in the entire intrinsic layer of the solar cell. The influence of the process pressure on the incorporation of nanocrystals and their distribution is also investigated. Thanks to APT we could determine crystalline fractions as low as 4.2% in the pm-Si:H films, which is very difficult to determine by standard techniques, such as X-ray diffraction, Raman spectroscopy, and spectroscopic ellipsometry. Moreover, we also demonstrate a sharp p/i interface in our solar cells.

  14. Correlations between fuel pins irradiated in fast and thermal fluxes using the frump fuel pin modelling program

    International Nuclear Information System (INIS)

    Hayns, M.R.; Adam, J.

    1975-08-01

    There is no experimental facilities in which a fuel pin can be irradiated in a fast environment under well defined conditions of over power or flow run down. Consequently most of the infor mation which is being accumulated on the behaviour of fuel pins under severe conditions is obtained from either capsule or loop rigs in thermal reactors. It is the purpose of this paper to highlight the differences between the behaviour of fuel pins irradiated in a thermal flux and a fast flux. A typical set of conditions is taken from an overpower experiment in a thermal flux and the behaviour of the system is analysed using the fuel modelling program FRUMP. A second numerical experiment is then performed in which the same conditions prevail, except that a fast flux is assumed, the criterion for comparison being that the total power input to the system is the same in both cases. From the many possible correlations which result from such an exercise the fuel tempreature has been selected to highlight various important features of the two irradiations. It is demonstrated that the flux depression can cause differences in the pin behaviour, even to altering the order of events in a transient. For example fuel melting will occur at different times and at different positions in the fuel in the two cases. It is concluded that the techniques of fuel modelling, as typified in the program FRUMP can provide a very useful tool indeed for the analysis of such experiments and for guiding the establishment of the appropriate correlations for the extrapolation to the fast flux case. (author)

  15. X-ray measurement with Pin type semiconductor detectors; Medicion de rayos X con detectores de semiconductor tipo PIN

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez J, F.J. [Instituto Nacional de Investigaciones Nucleares, Departamento de Electronica, C.P. 52045 Salazar, Estado de Mexico (Mexico)

    2000-07-01

    Here are presented the experimental results of the applications of Pin type radiation detectors developed in a National Institute of Nuclear Research (ININ) project, in the measurement of low energy gamma and X-rays. The applications were oriented mainly toward the Medical Physics area. It is planned other applications which are in process of implementation inside the National Institute of Nuclear Research in Mexico. (Author)

  16. New KID dosemeter for measurement of cosmic dosimetry

    International Nuclear Information System (INIS)

    Peksova, D.; Kakona, M.; Krist, P.; Kocur, Z.; Larina, K. V.; Ploc, O.

    2018-01-01

    The KID dosemeter is a small semiconductor low-power detector developed for common use. The current design is special designed after measuring cosmic rays on aircraft decks. The design concept is the same world-class devices Internet of Things (IoT). As a detection element detector were tested three variants a) PIN HAMAMATSU S2744-09 photodiode, b) 9 parallel Vishay photodiodes TEMD5080X01, c) 16 Vishay photodiode TEMD5080X01 again in parallel connection. All variants are silicon PIN photodiode. (authors)

  17. Silicon micromachined vibrating gyroscopes

    Science.gov (United States)

    Voss, Ralf

    1997-09-01

    This work gives an overview of silicon micromachined vibrating gyroscopes. Market perspectives and fields of application are pointed out. The advantage of using silicon micromachining is discussed and estimations of the desired performance, especially for automobiles are given. The general principle of vibrating gyroscopes is explained. Vibrating silicon gyroscopes can be divided into seven classes. for each class the characteristic principle is presented and examples are given. Finally a specific sensor, based on a tuning fork for automotive applications with a sensitivity of 250(mu) V/degrees is described in detail.

  18. Porous silicon gettering

    Energy Technology Data Exchange (ETDEWEB)

    Tsuo, Y.S.; Menna, P.; Pitts, J.R. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    The authors have studied a novel extrinsic gettering method that uses the large surface areas produced by a porous-silicon etch as gettering sites. The annealing step of the gettering used a high-flux solar furnace. They found that a high density of photons during annealing enhanced the impurity diffusion to the gettering sites. The authors used metallurgical-grade Si (MG-Si) prepared by directional solidification casing as the starting material. They propose to use porous-silicon-gettered MG-Si as a low-cost epitaxial substrate for polycrystalline silicon thin-film growth.

  19. Silicon etch process

    International Nuclear Information System (INIS)

    Day, D.J.; White, J.C.

    1984-01-01

    A silicon etch process wherein an area of silicon crystal surface is passivated by radiation damage and non-planar structure produced by subsequent anisotropic etching. The surface may be passivated by exposure to an energetic particle flux - for example an ion beam from an arsenic, boron, phosphorus, silicon or hydrogen source, or an electron beam. Radiation damage may be used for pattern definition and/or as an etch stop. Ethylenediamine pyrocatechol or aqueous potassium hydroxide anisotropic etchants may be used. The radiation damage may be removed after etching by thermal annealing. (author)

  20. Silicon integrated circuit process

    International Nuclear Information System (INIS)

    Lee, Jong Duck

    1985-12-01

    This book introduces the process of silicon integrated circuit. It is composed of seven parts, which are oxidation process, diffusion process, ion implantation process such as ion implantation equipment, damage, annealing and influence on manufacture of integrated circuit and device, chemical vapor deposition process like silicon Epitaxy LPCVD and PECVD, photolithography process, including a sensitizer, spin, harden bake, reflection of light and problems related process, infrared light bake, wet-etch, dry etch, special etch and problems of etching, metal process like metal process like metal-silicon connection, aluminum process, credibility of aluminum and test process.

  1. Silicon integrated circuit process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Duck

    1985-12-15

    This book introduces the process of silicon integrated circuit. It is composed of seven parts, which are oxidation process, diffusion process, ion implantation process such as ion implantation equipment, damage, annealing and influence on manufacture of integrated circuit and device, chemical vapor deposition process like silicon Epitaxy LPCVD and PECVD, photolithography process, including a sensitizer, spin, harden bake, reflection of light and problems related process, infrared light bake, wet-etch, dry etch, special etch and problems of etching, metal process like metal process like metal-silicon connection, aluminum process, credibility of aluminum and test process.

  2. Silicon nanowire hybrid photovoltaics

    KAUST Repository

    Garnett, Erik C.; Peters, Craig; Brongersma, Mark; Cui, Yi; McGehee, Mike

    2010-01-01

    Silicon nanowire Schottky junction solar cells have been fabricated using n-type silicon nanowire arrays and a spin-coated conductive polymer (PEDOT). The polymer Schottky junction cells show superior surface passivation and open-circuit voltages compared to standard diffused junction cells with native oxide surfaces. External quantum efficiencies up to 88% were measured for these silicon nanowire/PEDOT solar cells further demonstrating excellent surface passivation. This process avoids high temperature processes which allows for low-cost substrates to be used. © 2010 IEEE.

  3. Silicon nanowire hybrid photovoltaics

    KAUST Repository

    Garnett, Erik C.

    2010-06-01

    Silicon nanowire Schottky junction solar cells have been fabricated using n-type silicon nanowire arrays and a spin-coated conductive polymer (PEDOT). The polymer Schottky junction cells show superior surface passivation and open-circuit voltages compared to standard diffused junction cells with native oxide surfaces. External quantum efficiencies up to 88% were measured for these silicon nanowire/PEDOT solar cells further demonstrating excellent surface passivation. This process avoids high temperature processes which allows for low-cost substrates to be used. © 2010 IEEE.

  4. French approach in fuel pin modelling for fast reactors

    Energy Technology Data Exchange (ETDEWEB)

    Pascard, R [CEA-Centre de Fontenay-aux-Roses, Fontenay-aux-Roses (France)

    1979-12-01

    The purpose of this paper is to present the general philosophy on the problem of fuel modelling now prevailing in France after a twelve years period of tremendously increasing knowledge on fuel behavior. When the Rapsodie fuel pin was designed in 1962 , little was known about the behavior of a mixed oxide fuel pin under fast flux ; but a large body of knowledge on UO{sub 2} behavior in thermal reactor was available together with some sparse irradiation results on (U Pu)O{sub 2} in French experimental reactors. The performances assigned to the pin were then rather modest in rating (400 w/cm) and in burnup (30,000 MWd/t). The AISI 316 steel in solution annealed state was chosen as cladding material. The clad itself was supposed to deform by thermal creep due to fission gas pressure (100% release), and was affected consequently by a strain limit criteria. The importance of clad temperature ({approx}650 deg.) was considered only in connection with thermal creep, the possibility of a chemical reaction between mixed oxide and clad being at that time hardly suspected. Rapsodie had only been at full power for a few months when appeared the evidence of stainless steel swelling under a fast neutrons flux. This swelling was observed on Rapsodie pins as soon as they experienced sufficient neutrons dose, roughly one year later. This entirely new problem came immediately in the front stage (and is still of major importance today), and was at the origin of the change from the Rapsodie to the Fortissimo core in order to accelerate materials testing versus void swelling by multiplying the flux by a factor two. Even with unforeseen swelling, the design of the Rapsodie and later on Fortissimo pin, allowed not only to reach the goal burnup, but to increase it steadily to roughly 100,000 MWd/t. Since then, the French approach in fuel pin design has still retained something of its original simplicity, and technological efficiency, attitude which is justified by the following

  5. Establishing the need for an engineering standard for agricultural hitch pins.

    Science.gov (United States)

    Deboy, G R; Knapp, W M; Field, W E; Krutz, G W; Corum, C L

    2012-04-01

    Documented incidents have occurred in which failure or unintentional disengagement of agricultural hitch pins has contributed to property damage and personal injury. An examination of current hitch pin use on a convenience sample of farm operations in Indiana revealed a variety of non-standard, worn and damaged, and inappropriately sized hitch pins in use. Informal interviews with the farm operators confirmed that hitch pin misuse, failure, or disengagement is a relatively widespread problem that remains largely unaddressed. On-site observations also suggested a low use of hitch pin retaining devices or safety chains. A review of prior research revealed that little attention has been given to this problem, and currently no documentation allows for an estimate of the frequency or severity of losses associated with hitch pin misuse, failure, or disengagement. No specific engineering standards were found that directly applied to the design, appropriate selection, or loading capacity of agricultural hitch pins. Major suppliers of replacement hitch pins currently provide little or no information on matching hitch pin size to intended applications, and most replacement hitch pins examined were of foreign origin, with the overwhelming majority imported from China or India. These replacement hitch pins provided no specifications other than diameter, length, and, in some cases, labeling that indicated that the pins had been "heat treated. " Testing of a sample of 11 commercially available replacement hitch pins found variation along the length of the pin shaft and between individual pins in surface hardness, a potential predictor of pin failure. Examination of 17 commercially available replacement pins also revealed a variety of identifiers used to describe pin composition and fabrication methods, e.g., "heat treated." None of the pins examined provided any specifications on loading capacity. It was therefore concluded that there is a need to develop an agricultural hitch

  6. Joining elements of silicon carbide

    International Nuclear Information System (INIS)

    Olson, B.A.

    1979-01-01

    A method of joining together at least two silicon carbide elements (e.g.in forming a heat exchanger) is described, comprising subjecting to sufficiently non-oxidizing atmosphere and sufficiently high temperature, material placed in space between the elements. The material consists of silicon carbide particles, carbon and/or a precursor of carbon, and silicon, such that it forms a joint joining together at least two silicon carbide elements. At least one of the elements may contain silicon. (author)

  7. Postirradiation examinations of fuel pins from the GCFR F-1 series of mixed-oxide fuel pins at 5.5 at. % burnup

    International Nuclear Information System (INIS)

    Strain, R.V.; Johnson, C.E.

    1978-05-01

    Postirradiation examinations were performed on five fuel pins from the Gas-Cooled Fast-Breeder Reactor F-1 experiment irradiated in EBR-II to a peak burnup of approximately 5.5 at. %. These encapsulated fuel pins were irradiated at peak-power linear ratings from approximately 13 to 15 kW/ft and peak cladding inside diameter temperatures from approximately 625 to 760 0 C. The maximum diametral change that occurred during irradiation was 0.2% ΔD/D 0 . The maximum fuel-cladding chemical interaction depth was 2.6 mils in fuel pin G-1 and 1 mil or less in the other three pins examined destructively. Significant migration of the volatile fission products occurred axially to the fuel-blanket interfaces. Teh postirradiation examination data indicate that fuel melted at the inner surface of the annular fuel pellets in the two highest power rating fuel pins, but little axial movement of fuel occurred

  8. Thermal and stress analyses in thermoelectric generator with tapered and rectangular pin configurations

    International Nuclear Information System (INIS)

    Yilbas, Bekir Sami; Akhtar, S.S.; Sahin, A.Z.

    2016-01-01

    Thermal stress developed in thermoelectric generators is critical for long service applications. High temperature gradients, due to a large temperature difference across the junctions, causes excessive stress levels developed in the device pins and electrodes at the interfaces. In the present study, a thermoelectric generator with horizontal pin configuration is considered and thermal stress analysis in the device is presented. Ceramic wafer is considered to resemble the high temperature plate and copper electrodes are introduced at the pin junctions to reduce the electrical resistance between the pins and the high and low temperature junction plates during the operation. Finite element code is used to simulate temperature and stress fields in the thermoelectric generator. In the simulations, convection and radiation losses from the thermoelectric pins are considered and bismuth telluride pin material with and without tapering is incorporated. It is found that von Mises stress attains high values at the interface between the hot and cold junctions and the copper electrodes. Thermal stress developed in tapered pin configuration attains lower values than that of rectangular pin cross-section. - Highlights: • Different cold junction temperatures improves thermoelectric generator performance. • von Mises stress remains high across copper electrodes and hot junction ceramics. • von Mises stress reduces along pin length towards cold junction. • Pin tapering lowers stress levels in thermoelectric generator.

  9. Excessive Cellular S-nitrosothiol Impairs Endocytosis of Auxin Efflux Transporter PIN2

    Directory of Open Access Journals (Sweden)

    Min Ni

    2017-11-01

    Full Text Available S-nitrosoglutathione reductase (GSNOR1 is the key enzyme that regulates cellular levels of S-nitrosylation across kingdoms. We have previously reported that loss of GSNOR1 resulted in impaired auxin signaling and compromised auxin transport in Arabidopsis, leading to the auxin-related morphological phenotypes. However, the molecular mechanism underpinning the compromised auxin transport in gsnor1-3 mutant is still unknown. Endocytosis of plasma-membrane (PM-localized efflux PIN proteins play critical roles in auxin transport. Therefore, we investigate whether loss of GSNOR1 function has any effects on the endocytosis of PIN-FORMED (PIN proteins. It was found that the endocytosis of either the endogenous PIN2 or the transgenically expressed PIN2-GFP was compromised in the root cells of gsnor1-3 seedlings relative to Col-0. The internalization of PM-associated PIN2 or PIN2-GFP into Brefeldin A (BFA bodies was significantly reduced in gsnor1-3 upon BFA treatment in a manner independent of de novo protein synthesis. In addition, the exogenously applied GSNO not only compromised the endocytosis of PIN2-GFP but also inhibited the root elongation in a concentration-dependent manner. Taken together, our results indicate that, besides the reduced PIN2 level, one or more compromised components in the endocytosis pathway could account for the reduced endocytosis of PIN2 in gsnor1-3.

  10. A three-dimensional pin-wise analysis for CEA ejection accident

    Energy Technology Data Exchange (ETDEWEB)

    Park, Guen-Tae; Park, Min-Ho; Park, Jin-Woo; Um, Kil-Sup; Choi, Tong-Soo [KEPCO NF, Daejeon (Korea, Republic of)

    2016-10-15

    The ejection of a control element assembly (CEA) with high reactivity worth causes the sudden insertion of reactivity into the core. Immediately after the CEA ejection, the nuclear power of the reactor dramatically increases in an exponential behavior until the doppler effect becomes important and turns the reactivity balance and power down to lower levels. The 3-D CEA ejection analysis methodology has been developed using the multi-dimensional code coupling system, CHASER, which couples three dimensional core neutron kinetics code ASTRA, subchannel analysis code THALES, and fuel performance analysis code FROST using message passing interface (MPI). This paper presents the pin-by-pin level analysis result with the 3-D CEA ejection analysis methodology using the CHASER. The pin-by-pin level analysis consists of DNBR, enthalpy and Pellet/Clad Mechanical Interaction (PCMI) analysis. All the evaluations are simulated for APR1400 plant loaded with PLUS7 fuel. In this paper, the pin-by-pin analysis using the multidimensional core transient code, CHASER, is presented with respect to enthalpy, DNBR and PCMI for APR1400 plant loaded with PLUS7 fuel. For the pin-by-pin enthalpy and DNBR analysis, the quarter core for HFP case or 15 - 20 assemblies around the most severe assembly for part powers or HZP cases are selected. And PCMI calculation is performed for all the rods in the whole core during a conservative time period. The pin-by-pin analysis results show that the regulatory guidelines of CEA ejection accident are satisfied.

  11. Relationships between head fixation pins for radiosurgery and the skull bone. Usefulness of a torque wrench

    International Nuclear Information System (INIS)

    Toyota, Shun; Seta, Hidetoshi; Muramatsu, Masatoshi; Kubo, Hitoshi; Takeda, Kan

    2003-01-01

    In stereotactic radiosurgery (SRS), fixation devices are secured to the patient's head with pins. However, there have been no standards for the use of such pins, which must be inserted with appropriate torque based on the surgeon's clinical judgment. Therefore, the pins may sometimes be tightened excessively and penetrate too deeply into the patient's skull. To improve safety in SRS, a torque wrench was used for pin insertion. The usefulness of the torque wrench was then evaluated by examining the relationships between the pins and skull bone and identifying differences according to the wrench used and the patient's bone thickness. CT images of patients who had previously undergone SRS were used to assess the relationships between the pins and skull bone. Differences according to the wrench used and pin insertion site were investigated. Compared with a standard wrench, use of the torque wrench decreased the insertion depth of pins in the skull bone. In terms of site, pins in the forehead were inserted more deeply. No differences related to the frontal sinus were observed. The use of a torque wrench improved safety during pin insertion for SRS procedures. (author)

  12. Finite Element Analysis of Laser Engineered Net Shape (LENS™) Tungsten Clad Squeeze Pins

    Science.gov (United States)

    Sakhuja, Amit; Brevick, Jerald R.

    2004-06-01

    In the aluminum high-pressure die-casting and indirect squeeze casting processes, local "squeeze" pins are often used to minimize internal solidification shrinkage in heavy casting sections. Squeeze pins frequently fail in service due to molten aluminum adhering to the H13 tool steel pins ("soldering"). A wide variety of coating materials and methods have been developed to minimize soldering on H13. However, these coatings are typically very thin, and experience has shown their performance on squeeze pins is highly variable. The LENS™ process was employed in this research to deposit a relatively thick tungsten cladding on squeeze pins. An advantage of this process was that the process parameters could be precisely controlled in order to produce a satisfactory cladding. Two fixtures were designed and constructed to enable the end and outer diameter (OD) of the squeeze pins to be clad. Analyses were performed on the clad pins to evaluate the microstructure and chemical composition of the tungsten cladding and the cladding-H13 substrate interface. A thermo-mechanical finite element analysis (FEA) was performed to assess the stress distribution as a function of cladding thickness on the pins during a typical casting thermal cycle. FEA results were validated via a physical test, where the clad squeeze pins were immersed into molten aluminum. Pins subjected to the test were evaluated for thermally induced cracking and resistance to soldering of the tungsten cladding.

  13. Finite element analysis of laser engineered net shape (LENSTM) tungsten clad squeeze pins

    International Nuclear Information System (INIS)

    Sakhuja, Amit; Brevick, Jerald R.

    2004-01-01

    In the aluminum high-pressure die-casting and indirect squeeze casting processes, local 'squeeze' pins are often used to minimize internal solidification shrinkage in heavy casting sections. Squeeze pins frequently fail in service due to molten aluminum adhering to the H13 tool steel pins ('soldering'). A wide variety of coating materials and methods have been developed to minimize soldering on H13. However, these coatings are typically very thin, and experience has shown their performance on squeeze pins is highly variable. The LENS TM process was employed in this research to deposit a relatively thick tungsten cladding on squeeze pins. An advantage of this process was that the process parameters could be precisely controlled in order to produce a satisfactory cladding. Two fixtures were designed and constructed to enable the end and outer diameter (OD) of the squeeze pins to be clad. Analyses were performed on the clad pins to evaluate the microstructure and chemical composition of the tungsten cladding and the cladding-H13 substrate interface. A thermo-mechanical finite element analysis (FEA) was performed to assess the stress distribution as a function of cladding thickness on the pins during a typical casting thermal cycle. FEA results were validated via a physical test, where the clad squeeze pins were immersed into molten aluminum. Pins subjected to the test were evaluated for thermally induced cracking and resistance to soldering of the tungsten cladding

  14. Liquid-metal pin-fin pressure drop by correlation in cross flow

    International Nuclear Information System (INIS)

    Wang, Zhibi; Kuzay, T.M.; Assoufid, L.

    1994-01-01

    The pin-fin configuration is widely used as a heat transfer enhancement method in high-heat-flux applications. Recently, the pin-fin design with liquid-metal coolant was also applied to synchrotron-radiation beamline devices. This paper investigates the pressure drop in a pin-post design beamline mirror with liquid gallium as the coolant. Because the pin-post configuration is a relatively new concept, information in literature about pin-post mirrors or crystals is rare, and information about the pressure drop in pin-post mirrors with liquid metal as the coolant is even more sparse. Due to this the authors considered the cross flow in cylinder-array geometry, which is very similar to that of the pin-post, to examine the pressure drop correlation with liquid metals over pin fins. The cross flow of fluid with various fluid characteristics or properties through a tube bank was studied so that the results can be scaled to the pin-fin geometry with liquid metal as the coolant. Study lead to two major variables to influence the pressure drop: fluid properties, viscosity and density, and the relative length of the posts. Correlation of the pressure drop between long and short posts and the prediction of the pressure drop of liquid metal in the pin-post mirror and comparison with an existing experiment are addressed

  15. Displaced humeral lateral condyle fractures in children: should we bury the pins?

    Science.gov (United States)

    Das De, Soumen; Bae, Donald S; Waters, Peter M

    2012-09-01

    The purpose of this investigation was to determine if leaving Kirschner wires exposed is more cost-effective than burying them subcutaneously after open reduction and internal fixation (ORIF) of humeral lateral condyle fractures. A retrospective cohort study of all lateral condyle fractures treated over a 10-year period at a single institution was performed. Data on surgical technique, fracture healing, and complications were analyzed, as well as treatment costs. A decision analysis model was then constructed to compare the strategies of leaving the pins exposed versus buried. Finally, sensitivity analyses were performed, assessing cost-effectiveness when infection rates and costs of treating deep infections were varied. A total of 235 children with displaced fractures were treated with ORIF using Kirschner wires. Pins were left exposed in 41 cases (17.4%) and buried in 194 cases (82.6%); the age, sex, injury mechanisms, and fracture patterns were similar in both the groups. The median time to removal of implants was shorter with exposed versus buried pins (4 vs. 6 wk, Pfracture union or loss of reduction rates. The rate of superficial infection was higher with exposed pins (9.8% vs. 3.1%), but this was not statistically significant (P=0.076). There were no deep infections with exposed pins, whereas the rate of deep infection was 0.5% with buried pins (P=1.00). Buried pins were associated with additional complications, including symptomatic implants (7.2%); pins protruding through the skin (16%); internal pin migration necessitating additional surgery (1%); and skin necrosis (1%). The decision analysis revealed that leaving pins exposed resulted in an average cost savings of $3442 per patient. This strategy remained cost-effective even when infection rates with exposed pins approached 40%. Leaving the pins exposed after ORIF of lateral condyle fractures is safe and more cost-effective than burying the pins subcutaneously. Retrospective cohort study (level III).

  16. Photoluminescence and electrical properties of silicon oxide and silicon nitride superlattices containing silicon nanocrystals

    International Nuclear Information System (INIS)

    Shuleiko, D V; Ilin, A S

    2016-01-01

    Photoluminescence and electrical properties of superlattices with thin (1 to 5 nm) alternating silicon-rich silicon oxide or silicon-rich silicon nitride, and silicon oxide or silicon nitride layers containing silicon nanocrystals prepared by plasma-enhanced chemical vapor deposition with subsequent annealing were investigated. The entirely silicon oxide based superlattices demonstrated photoluminescence peak shift due to quantum confinement effect. Electrical measurements showed the hysteresis effect in the vicinity of zero voltage due to structural features of the superlattices from SiOa 93 /Si 3 N 4 and SiN 0 . 8 /Si 3 N 4 layers. The entirely silicon nitride based samples demonstrated resistive switching effect, comprising an abrupt conductivity change at about 5 to 6 V with current-voltage characteristic hysteresis. The samples also demonstrated efficient photoluminescence with maximum at ∼1.4 eV, due to exiton recombination in silicon nanocrystals. (paper)

  17. Advances in silicon nanophotonics

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher; Pu, Minhao

    Silicon has long been established as an ideal material for passive integrated optical circuitry due to its high refractive index, with corresponding strong optical confinement ability, and its low-cost CMOS-compatible manufacturability. However, the inversion symmetry of the silicon crystal lattice.......g. in high-bit-rate optical communication circuits and networks, it is vital that the nonlinear optical effects of silicon are being strongly enhanced. This can among others be achieved in photonic-crystal slow-light waveguides and in nano-engineered photonic-wires (Fig. 1). In this talk I shall present some...... recent advances in this direction. The efficient coupling of light between optical fibers and the planar silicon devices and circuits is of crucial importance. Both end-coupling (Fig. 1) and grating-coupling solutions will be discussed along with polarization issues. A new scheme for a hybrid III...

  18. Integrated silicon optoelectronics

    CERN Document Server

    Zimmermann, Horst

    2000-01-01

    'Integrated Silicon Optoelectronics'assembles optoelectronics and microelectronics The book concentrates on silicon as the major basis of modern semiconductor devices and circuits Starting from the basics of optical emission and absorption and from the device physics of photodetectors, the aspects of the integration of photodetectors in modern bipolar, CMOS, and BiCMOS technologies are discussed Detailed descriptions of fabrication technologies and applications of optoelectronic integrated circuits are included The book, furthermore, contains a review of the state of research on eagerly expected silicon light emitters In order to cover the topic of the book comprehensively, integrated waveguides, gratings, and optoelectronic power devices are included in addition Numerous elaborate illustrations promote an easy comprehension 'Integrated Silicon Optoelectronics'will be of value to engineers, physicists, and scientists in industry and at universities The book is also recommendable for graduate students speciali...

  19. Silicon microfabricated beam expander

    International Nuclear Information System (INIS)

    Othman, A.; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A.; Ain, M. F.

    2015-01-01

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed

  20. Silicon microfabricated beam expander

    Science.gov (United States)

    Othman, A.; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A.; Ain, M. F.

    2015-03-01

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed.

  1. Silicon microfabricated beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Othman, A., E-mail: aliman@ppinang.uitm.edu.my; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A. [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40450, Shah Alam, Selangor (Malaysia); Ain, M. F. [School of Electrical and Electronic Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300,Nibong Tebal, Pulau Pinang (Malaysia)

    2015-03-30

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed.

  2. Porous Silicon Nanowires

    Science.gov (United States)

    Qu, Yongquan; Zhou, Hailong; Duan, Xiangfeng

    2011-01-01

    In this minreview, we summarize recent progress in the synthesis, properties and applications of a new type of one-dimensional nanostructures — single crystalline porous silicon nanowires. The growth of porous silicon nanowires starting from both p- and n-type Si wafers with a variety of dopant concentrations can be achieved through either one-step or two-step reactions. The mechanistic studies indicate the dopant concentration of Si wafers, oxidizer concentration, etching time and temperature can affect the morphology of the as-etched silicon nanowires. The porous silicon nanowires are both optically and electronically active and have been explored for potential applications in diverse areas including photocatalysis, lithium ion battery, gas sensor and drug delivery. PMID:21869999

  3. Tribology of silicon-thin-film-coated SiC ceramics and the effects of high energy ion irradiation

    International Nuclear Information System (INIS)

    Kohzaki, Masao; Noda, Shoji; Doi, Harua

    1990-01-01

    The sliding friction coefficients and specific wear of SiC ceramics coated with a silicon thin film (Si/SiC) with and without subsequent Ar + irradiation against a diamond pin were measured with a pin-on-disk tester at room temperature in laboratory air of approximately 50% relative humidity without oil lubrication for 40 h. The friction coefficient of Ar + -irradiated Si/SiC was about 0.05 with a normal load of 9.8 N and remained almost unchanged during the 40 h test, while that of SiC increased from 0.04 to 0.12 during the test. The silicon deposition also reduced the specific wear of SiC to less than one tenth of that of the uncoated SiC. Effectively no wear was detected in Si/SiC irradiated to doses of over 2x10 16 ions cm -2 . (orig.)

  4. Substrate and p-layer effects on polymorphous silicon solar cells

    Directory of Open Access Journals (Sweden)

    Abolmasov S.N.

    2014-07-01

    Full Text Available The influence of textured transparent conducting oxide (TCO substrate and p-layer on the performance of single-junction hydrogenated polymorphous silicon (pm-Si:H solar cells has been addressed. Comparative studies were performed using p-i-n devices with identical i/n-layers and back reflectors fabricated on textured Asahi U-type fluorine-doped SnO2, low-pressure chemical vapor deposited (LPCVD boron-doped ZnO and sputtered/etched aluminum-doped ZnO substrates. The p-layers were hydrogenated amorphous silicon carbon and microcrystalline silicon oxide. As expected, the type of TCO and p-layer both have a great influence on the initial conversion efficiency of the solar cells. However they have no effect on the defect density of the pm-Si:H absorber layer.

  5. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    Energy Technology Data Exchange (ETDEWEB)

    Baszczyk, M., E-mail: baszczyk@agh.edu.pl [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Dorosz, P.; Glab, S.; Kucewicz, W. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Mik, L. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); State Higher Vocational School, Tarnow (Poland); Sapor, M. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland)

    2016-07-11

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  6. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    Science.gov (United States)

    Baszczyk, M.; Dorosz, P.; Glab, S.; Kucewicz, W.; Mik, L.; Sapor, M.

    2016-07-01

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  7. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    International Nuclear Information System (INIS)

    Baszczyk, M.; Dorosz, P.; Glab, S.; Kucewicz, W.; Mik, L.; Sapor, M.

    2016-01-01

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  8. Radiation Hardness tests with neutron flux on different Silicon photomultiplier devices

    Science.gov (United States)

    Cattaneo, P. W.; Cervi, T.; Menegolli, A.; Oddone, M.; Prata, M.; Prata, M. C.; Rossella, M.

    2017-07-01

    Radiation hardness is an important requirement for solid state readout devices operating in high radiation environments common in particle physics experiments. The MEG II experiment, at PSI, Switzerland, investigates the forbidden decay μ+ → e+ γ. Exploiting the most intense muon beam of the world. A significant flux of non-thermal neutrons (kinetic energy Ek>= 0.5 MeV) is present in the experimental hall produced along the beam-line and in the hall itself. We present the effects of neutron fluxes comparable to the MEG II expected doses on several Silicon Photomultiplier (SiPMs). The tested models are: AdvanSiD ASD-NUV3S-P50 (used in MEG II experiment), AdvanSiD ASD-NUV3S-P40, AdvanSiD ASD-RGB3S-P40, Hamamatsu and Excelitas C30742-33-050-X. The neutron source is the thermal Sub-critical Multiplication complex (SM1) moderated with water, located at the University of Pavia (Italy). We report the change of SiPMs most important electric parameters: dark current, dark pulse frequency, gain, direct bias resistance, as a function of the integrated neutron fluency.

  9. Nanostructured silicon for thermoelectric

    Science.gov (United States)

    Stranz, A.; Kähler, J.; Waag, A.; Peiner, E.

    2011-06-01

    Thermoelectric modules convert thermal energy into electrical energy and vice versa. At present bismuth telluride is the most widely commercial used material for thermoelectric energy conversion. There are many applications where bismuth telluride modules are installed, mainly for refrigeration. However, bismuth telluride as material for energy generation in large scale has some disadvantages. Its availability is limited, it is hot stable at higher temperatures (>250°C) and manufacturing cost is relatively high. An alternative material for energy conversion in the future could be silicon. The technological processing of silicon is well advanced due to the rapid development of microelectronics in recent years. Silicon is largely available and environmentally friendly. The operating temperature of silicon thermoelectric generators can be much higher than of bismuth telluride. Today silicon is rarely used as a thermoelectric material because of its high thermal conductivity. In order to use silicon as an efficient thermoelectric material, it is necessary to reduce its thermal conductivity, while maintaining high electrical conductivity and high Seebeck coefficient. This can be done by nanostructuring into arrays of pillars. Fabrication of silicon pillars using ICP-cryogenic dry etching (Inductive Coupled Plasma) will be described. Their uniform height of the pillars allows simultaneous connecting of all pillars of an array. The pillars have diameters down to 180 nm and their height was selected between 1 micron and 10 microns. Measurement of electrical resistance of single silicon pillars will be presented which is done in a scanning electron microscope (SEM) equipped with nanomanipulators. Furthermore, measurement of thermal conductivity of single pillars with different diameters using the 3ω method will be shown.

  10. Study on Silicon detectors

    International Nuclear Information System (INIS)

    Gervino, G.; Boero, M.; Manfredotti, C.; Icardi, M.; Gabutti, A.; Bagnolatti, E.; Monticone, E.

    1990-01-01

    Prototypes of Silicon microstrip detectors and Silicon large area detectors (3x2 cm 2 ), realized directly by our group, either by ion implantation or by diffusion are presented. The physical detector characteristics and their performances determined by exposing them to different radioactive sources and the results of extensive tests on passivation, where new technological ways have been investigated, are discussed. The calculation of the different terms contributing to the total dark current is reported

  11. Subwavelength silicon photonics

    International Nuclear Information System (INIS)

    Cheben, P.; Bock, P.J.; Schmid, J.H.; Lapointe, J.; Janz, S.; Xu, D.-X.; Densmore, A.; Delage, A.; Lamontagne, B.; Florjanczyk, M.; Ma, R.

    2011-01-01

    With the goal of developing photonic components that are compatible with silicon microelectronic integrated circuits, silicon photonics has been the subject of intense research activity. Silicon is an excellent material for confining and manipulating light at the submicrometer scale. Silicon optoelectronic integrated devices have the potential to be miniaturized and mass-produced at affordable cost for many applications, including telecommunications, optical interconnects, medical screening, and biological and chemical sensing. We review recent advances in silicon photonics research at the National Research Council Canada. A new type of optical waveguide is presented, exploiting subwavelength grating (SWG) effect. We demonstrate subwavelength grating waveguides made of silicon, including practical components operating at telecom wavelengths: input couplers, waveguide crossings and spectrometer chips. SWG technique avoids loss and wavelength resonances due to diffraction effects and allows for single-mode operation with direct control of the mode confinement by changing the refractive index of a waveguide core over a range as broad as 1.6 - 3.5 simply by lithographic patterning. The light can be launched to these waveguides with a coupling loss as small as 0.5 dB and with minimal wavelength dependence, using coupling structures similar to that shown in Fig. 1. The subwavelength grating waveguides can cross each other with minimal loss and negligible crosstalk which allows massive photonic circuit connectivity to overcome the limits of electrical interconnects. These results suggest that the SWG waveguides could become key elements for future integrated photonic circuits. (authors)

  12. Silicon microphotonic waveguides

    International Nuclear Information System (INIS)

    Ta'eed, V.; Steel, M.J.; Grillet, C.; Eggleton, B.; Du, J.; Glasscock, J.; Savvides, N.

    2004-01-01

    Full text: Silicon microphotonic devices have been drawing increasing attention in the past few years. The high index-difference between silicon and its oxide (Δn = 2) suggests a potential for high-density integration of optical functions on to a photonic chip. Additionally, it has been shown that silicon exhibits strong Raman nonlinearity, a necessary property as light interaction can occur only by means of nonlinearities in the propagation medium. The small dimensions of silicon waveguides require the design of efficient tapers to couple light to them. We have used the beam propagation method (RSoft BeamPROP) to understand the principles and design of an inverse-taper mode-converter as implemented in several recent papers. We report on progress in the design and fabrication of silicon-based waveguides. Preliminary work has been conducted by patterning silicon-on-insulator (SOI) wafers using optical lithography and reactive ion etching. Thus far, only rib waveguides have been designed, as single-mode ridge-waveguides are beyond the capabilities of conventional optical lithography. We have recently moved to electron beam lithography as the higher resolutions permitted will provide the flexibility to begin fabricating sub-micron waveguides

  13. Amorphous silicon crystalline silicon heterojunction solar cells

    CERN Document Server

    Fahrner, Wolfgang Rainer

    2013-01-01

    Amorphous Silicon/Crystalline Silicon Solar Cells deals with some typical properties of heterojunction solar cells, such as their history, the properties and the challenges of the cells, some important measurement tools, some simulation programs and a brief survey of the state of the art, aiming to provide an initial framework in this field and serve as a ready reference for all those interested in the subject. This book helps to "fill in the blanks" on heterojunction solar cells. Readers will receive a comprehensive overview of the principles, structures, processing techniques and the current developmental states of the devices. Prof. Dr. Wolfgang R. Fahrner is a professor at the University of Hagen, Germany and Nanchang University, China.

  14. Oxygen defect processes in silicon and silicon germanium

    KAUST Repository

    Chroneos, A.; Sgourou, E. N.; Londos, C. A.; Schwingenschlö gl, Udo

    2015-01-01

    Silicon and silicon germanium are the archetypical elemental and alloy semiconductor materials for nanoelectronic, sensor, and photovoltaic applications. The investigation of radiation induced defects involving oxygen, carbon, and intrinsic defects is important for the improvement of devices as these defects can have a deleterious impact on the properties of silicon and silicon germanium. In the present review, we mainly focus on oxygen-related defects and the impact of isovalent doping on their properties in silicon and silicon germanium. The efficacy of the isovalent doping strategies to constrain the oxygen-related defects is discussed in view of recent infrared spectroscopy and density functional theory studies.

  15. Colloidal characterization of ultrafine silicon carbide and silicon nitride powders

    Science.gov (United States)

    Whitman, Pamela K.; Feke, Donald L.

    1986-01-01

    The effects of various powder treatment strategies on the colloid chemistry of aqueous dispersions of silicon carbide and silicon nitride are examined using a surface titration methodology. Pretreatments are used to differentiate between the true surface chemistry of the powders and artifacts resulting from exposure history. Silicon nitride powders require more extensive pretreatment to reveal consistent surface chemistry than do silicon carbide powders. As measured by titration, the degree of proton adsorption from the suspending fluid by pretreated silicon nitride and silicon carbide powders can both be made similar to that of silica.

  16. Oxygen defect processes in silicon and silicon germanium

    KAUST Repository

    Chroneos, A.

    2015-06-18

    Silicon and silicon germanium are the archetypical elemental and alloy semiconductor materials for nanoelectronic, sensor, and photovoltaic applications. The investigation of radiation induced defects involving oxygen, carbon, and intrinsic defects is important for the improvement of devices as these defects can have a deleterious impact on the properties of silicon and silicon germanium. In the present review, we mainly focus on oxygen-related defects and the impact of isovalent doping on their properties in silicon and silicon germanium. The efficacy of the isovalent doping strategies to constrain the oxygen-related defects is discussed in view of recent infrared spectroscopy and density functional theory studies.

  17. Measurement and Simulation of the Variation in Proton-Induced Energy Deposition in Large Silicon Diode Arrays

    Science.gov (United States)

    Howe, Christina L.; Weller, Robert A.; Reed, Robert A.; Sierawski, Brian D.; Marshall, Paul W.; Marshall, Cheryl J.; Mendenhall, Marcus H.; Schrimpf, Ronald D.

    2007-01-01

    The proton induced charge deposition in a well characterized silicon P-i-N focal plane array is analyzed with Monte Carlo based simulations. These simulations include all physical processes, together with pile up, to accurately describe the experimental data. Simulation results reveal important high energy events not easily detected through experiment due to low statistics. The effects of each physical mechanism on the device response is shown for a single proton energy as well as a full proton space flux.

  18. Magnetic relaxation, flux pinning and critical currents in superconductors

    International Nuclear Information System (INIS)

    Lichtenberger, K.S.

    1991-01-01

    A systematic study of the magnetic flux pinning properties in superconductors has been undertaken in an attempt to understand the differences between the flux creep behavior of classical superconductors and high-temperature superconductors (HTSC's). In HTSC's, the ratio of the effective flux pinning energy to the thermal energy, U 0 /kT, is much smaller than that of conventional superconductors, often approaching unity. This results in much larger creep rates in HTSC's than in conventional superconductors. It is necessary to find suitable models that describe flux creep in both classical superconductors and HTSC's. Results show that while these two classes of materials are quantitatively very different, a single pinning barrier mode adequately describes both, within the proper region of the H-T plane. The model is applied to a variety of superconductors and the results are contrasted. Although the H-T plane appears to be very different HTSC's than for conventional superconductors, qualitatively the same physics describes both. In HTSC's, near the upper critical field there exists a relatively wide region of superconducting fluctuations, followed successively by regions of thermodynamic reversibility, thermally assisted flux, flux creep, and finally rigid flux lattice where little, if any, motion of the flux lattice occurs. All of these regions are also present in conventional superconductors, but often much more difficult, especially the irreversibility transition and the fluctuation region. The central finding of the flux creep analysis is that the region of flux creep is defined as a band in the H-T plane in which 2 ≤ U 0 /kT ≤ 100, and that the flux creep model applies best within this band

  19. Progress on DEMO blanket attachment concept with keys and pins

    International Nuclear Information System (INIS)

    Vizvary, Zsolt; Iglesias, Daniel; Cooper, David; Crowe, Robert; Riccardo, Valeria

    2015-01-01

    Highlights: • DEMO blanket attachment system with keys and pins (without using bolts). • Blanket segments are preloaded by progressively designed springs. • Blanket back plate flexibility has a major impact on spring design. • Mechanical analysis of other components indicates no unresolvable issues. • Thermal analysis indicates acceptable temperatures for the support system. - Abstract: The blanket attachment has to cope with gravity, thermal and electromagnetic loads, also it has to be installed and serviced by remote handling. Pre-stressed components suffer from stress relaxation in irradiated environments such as DEMO. To circumvent this problem pre-stressed component should be either avoided or shielded, and where possible keys and pins should be used. This strategy has been proposed for the DEMO multi-module segments (MMS). The blanket segments are held by two tapered keys each, designed to allow thermal expansions while providing contact with the vacuum vessel and to resist the poloidal and radial moments the latter being dominant at 9.1 MNm inboard and 15 MNm outboard. On the top of the blanket segment there is a pin which provides vertical support. At the bottom another vertical support has to lock them in position after installation and manage the pre-load on the segments. The pre-load is required to deal with the electromagnetic loads during disruption. This is provided by a set of springs, which require shielding as they are preloaded. These are sized to cope with the force (3 MN inboard, 1.4 MN outboard) due to halo currents and the toroidal moment which can reverse. Calculations show that the flexibility of the blanket segment itself plays a significant role in defining the required support system. The blanket segment acts as a preloaded spring and it has to be part of the attachment design as well.

  20. Spatial chaotic behavior of vortices in type-II superconductors with different pinning strength

    International Nuclear Information System (INIS)

    Lin, H.-T.; Pan, M.; Cheng, C.H.; Cui, Y.J.; Zhao, Y.

    2008-01-01

    Spatial chaotic character in systems where defects are arranged in periodic arrays has been investigated by computer simulation. Due to the high nonlinearity of the vortex-defect interaction, arrangement of the vortices in a periodic pinning array can be chaotic (glassy), depending on the vortex-defect interaction state and vortex-vortex interaction. Two types of disordered vortex states in the system are observed. The type-I disorder arises from the intrinsically chaotic nature of the nonlinear system, existing when the pinning disorder is low and the pinning strength is weak. The type-II disordered state is related to the pinning disorder, which is dominating when both the pinning disorder and the pinning strength are strong