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Sample records for annealed dilute systems

  1. Dynamics of ordering processes in annealed dilute systems: Island formation, vacancies at domain boundaries, and compactification

    DEFF Research Database (Denmark)

    Shah, Peter Jivan; Mouritsen, Ole G.

    1990-01-01

    The dynamics of the ordering processes in two-dimensional lattice models with annealed vacancies and nonconserved order parameter is studied as a function of temperature and vacancy concentration by means of Monte Carlo temperature-quenching simulations. The models are Ising antiferromagnets with...... ordering in thin films of Cu3Au alloys with extra Cu.......The dynamics of the ordering processes in two-dimensional lattice models with annealed vacancies and nonconserved order parameter is studied as a function of temperature and vacancy concentration by means of Monte Carlo temperature-quenching simulations. The models are Ising antiferromagnets with...... compactification via coalescence. The domain-size distribution function, which is approximately log-normal, is shown to obey dynamical scaling over a substantial time range for both types of ordering. The growth for the pure systems is found to be described by a power law with the classical growth exponent n=1...

  2. Simulated Annealing of Two Electron Density Solution Systems

    OpenAIRE

    Neto, Mario de Oliveira; Alonso, Ronaldo Luiz; Leite, Fabio Lima; Jr, Osvaldo N. Oliveira; Polikarpov, Igor; Mascarenhas, Yvonne Primerano

    2008-01-01

    Many structural studies have been performed with a combination of SAXS and simulated annealing to reconstruct three dimensional models. Simulated annealing is suitable for the study of monodisperse, diluted and two-electron densities systems. In this chapter we showed how the simulated annealing procedure can be used to minimize the discrepancy between two functions: the simulated intensity and the experimental one-dimensional SAXS curve. The goal was to find the most probable form for a prot...

  3. Reactor vessel annealing system

    Science.gov (United States)

    Miller, Phillip E.; Katz, Leonoard R.; Nath, Raymond J.; Blaushild, Ronald M.; Tatch, Michael D.; Kordalski, Frank J.; Wykstra, Donald T.; Kavalkovich, William M.

    1991-01-01

    A system for annealing a vessel (14) in situ by heating the vessel (14) to a defined temperature, composed of: an electrically operated heater assembly (10) insertable into the vessel (14) for heating the vessel (14) to the defined temperature; temperature monitoring components positioned relative to the heater assembly (10) for monitoring the temperature of the vessel (14); a controllable electric power supply unit (32-60) for supplying electric power required by the heater assembly (10); a control unit (80-86) for controlling the power supplied by the power supply unit (32-60); a first vehicle (2) containing the power supply unit (32-60); a second vehicle (4) containing the control unit (80-86); power conductors (18,22) connectable between the power supply unit (32-60) and the heater unit (10) for delivering the power supplied by the power supply unit (32-60) to the heater assembly (10); signal conductors (20,24) connectable between the temperature monitoring components and the control unit (80-86) for delivering temperature indicating signals from the temperature monitoring components to the control unit (80-86); and control conductors (8) connectable between the control unit (80-86) and the power supply unit (32-60) for delivering to the power supply unit (32-60) control signals for controlling the level of power supplied by the power supply unit (32-60) to the heater assembly (10).

  4. Ensemble annealing of complex physical systems

    OpenAIRE

    Habeck, Michael

    2015-01-01

    Algorithms for simulating complex physical systems or solving difficult optimization problems often resort to an annealing process. Rather than simulating the system at the temperature of interest, an annealing algorithm starts at a temperature that is high enough to ensure ergodicity and gradually decreases it until the destination temperature is reached. This idea is used in popular algorithms such as parallel tempering and simulated annealing. A general problem with annealing methods is th...

  5. Ensemble annealing of complex physical systems

    CERN Document Server

    Habeck, Michael

    2015-01-01

    Algorithms for simulating complex physical systems or solving difficult optimization problems often resort to an annealing process. Rather than simulating the system at the temperature of interest, an annealing algorithm starts at a temperature that is high enough to ensure ergodicity and gradually decreases it until the destination temperature is reached. This idea is used in popular algorithms such as parallel tempering and simulated annealing. A general problem with annealing methods is that they require a temperature schedule. Choosing well-balanced temperature schedules can be tedious and time-consuming. Imbalanced schedules can have a negative impact on the convergence, runtime and success of annealing algorithms. This article outlines a unifying framework, ensemble annealing, that combines ideas from simulated annealing, histogram reweighting and nested sampling with concepts in thermodynamic control. Ensemble annealing simultaneously simulates a physical system and estimates its density of states. The...

  6. Computer automation of a dilution cryogenic system

    International Nuclear Information System (INIS)

    This study has been realized in the framework of studies on developing new technic for low temperature detectors for neutrinos and dark matter. The principles of low temperature physics and helium 4 and dilution cryostats, are first reviewed. The cryogenic system used and the technic for low temperature thermometry and regulation systems are then described. The computer automation of the dilution cryogenic system involves: numerical measurement of the parameter set (pressure, temperature, flow rate); computer assisted operating of the cryostat and the pump bench; numerical regulation of pressure and temperature; operation sequence full automation allowing the system to evolve from a state to another (temperature descent for example)

  7. Special dilution refrigerator systems of Milli-Kelvin detector experiments

    International Nuclear Information System (INIS)

    Several hundred ultra low temperature systems have been designed and built for a variety of applications. One common application is the refrigeration of low temperature detectors. Although many of the requirements are satisfied by standard designs, Oxford Instruments has often built special refrigerators to suit specific detector requirements. A few of the most interesting of these systems will be discussed. (1) dilution refrigerators to cool gravitational wave antennae to 65 mK; (2) rotating dilution refrigerator for cosmic ray detector experiments; (3) compact dilution refrigerator to cool large bolometer arrays within the SCUBA telescope; (4) side access systems for beam line experiments

  8. Development of Digital Boron Dilution Alarm System (DBDAS)

    International Nuclear Information System (INIS)

    It is imperative that a reactor which has been shutdown remain subcritical and not inadvertently return to power. Such an event could occur for instance through failure of a component in the complex control system or inadvertent action taken by the operator. In any case, during such an event the reactor approaches criticality exponentially with respect to time thus making it more difficult for the operator to detect the event and take appropriate action before the reactor goes to criticality [Ref. 1]. This paper is prepared for the development of the Digital Boron Dilution Alarm System (DBDAS) to improve the sub-criticality monitoring of Advanced Power Reactor 1400 Standard Nuclear Power Plant (APR1400). This system is designed to provide operators with useful information about an inadvertent boron dilution event occurring with the plant in Modes 3, 4, 5, and 6 before the reactor coolant system is diluted sufficiently to result in a total loss of shutdown margin. The acceptance criteria of APR1400 for an unplanned boron (moderator) dilution specify at least 30 minutes in all operational modes. The main features of DBAS are the use of digital information from the startup neutron monitoring channels and a boronometer

  9. Development of Digital Boron Dilution Alarm System (DBDAS)

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ho Cheol; Lee, Hwan Soo; Moon, Chan Kook [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2012-05-15

    It is imperative that a reactor which has been shutdown remain subcritical and not inadvertently return to power. Such an event could occur for instance through failure of a component in the complex control system or inadvertent action taken by the operator. In any case, during such an event the reactor approaches criticality exponentially with respect to time thus making it more difficult for the operator to detect the event and take appropriate action before the reactor goes to criticality [Ref. 1]. This paper is prepared for the development of the Digital Boron Dilution Alarm System (DBDAS) to improve the sub-criticality monitoring of Advanced Power Reactor 1400 Standard Nuclear Power Plant (APR1400). This system is designed to provide operators with useful information about an inadvertent boron dilution event occurring with the plant in Modes 3, 4, 5, and 6 before the reactor coolant system is diluted sufficiently to result in a total loss of shutdown margin. The acceptance criteria of APR1400 for an unplanned boron (moderator) dilution specify at least 30 minutes in all operational modes. The main features of DBAS are the use of digital information from the startup neutron monitoring channels and a boronometer

  10. Isochronal annealing of electron-irradiated dilute Fe alloys modelled by an ab initio based AKMC method: Influence of solute-interstitial cluster properties

    International Nuclear Information System (INIS)

    The evolution of the microstructure of dilute Fe alloys under irradiation has been modelled using a multiscale approach based on ab initio and atomistic kinetic Monte Carlo simulations. In these simulations, both self interstitials and vacancies, isolated or in clusters, are considered. Isochronal annealing after electron irradiation experiments have been simulated in pure Fe, Fe-Cu and Fe-Mn dilute alloys, focusing on recovery stages I and II. The parameters regarding the self interstitial - solute atom interactions are based on ab initio predictions and some of these interactions have been slightly adjusted, without modifying the interaction character, on isochronal annealing experimental data. The different recovery peaks are globally well reproduced. These simulations allow interpreting the different recovery peaks as well as the effect of varying solute concentration. For some peaks, these simulations have allowed to revisit and re-interpret the experimental data. In Fe-Cu, the trapping of self interstitials by Cu atoms allows experimental results to be reproduced, although no mixed dumbbells are formed, contrary to the former interpretations. Whereas, in Fe-Mn, the favorable formation of mixed dumbbell plays an important role in the Mn effect.

  11. Effects of annealing atmosphere on structure, optical and magnetic properties of Zn0.95Cu0.02Cr0.03O diluted magnetic semiconductors

    International Nuclear Information System (INIS)

    Zn0.95Cu0.02Cr0.03O nanoparticles were successfully prepared by sol–gel method under different atmospheres (air and argon). X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, photoluminescence spectroscopy and vibrating sample magnetometer were used to investigate the effect of annealing atmospheres on the structure, optical and magnetic properties of Zn0.95Cu0.02Cr0.03O diluted magnetic semiconductors. The results showed that the Zn0.95Cu0.02Cr0.03O nanoparticles with 16.5 nm and 17.2 nm sintered in different atmospheres had a hexagonal wurtzite structure without any secondary phases. X-ray photoelectron spectroscopy analysis indicated that the Cr ions were the +3 and the Cu exhibits different valence state in the Zn0.95Cu0.02Cr0.03O samples annealed in different atmosphere. The annealing atmosphere was found to have effect on the optical and magnetic properties of the Zn0.95Cu0.02Cr0.03O samples

  12. Kinetic Monte Carlo simulation of nanostructural evolution under post-irradiation annealing in dilute FeMnNi

    Energy Technology Data Exchange (ETDEWEB)

    Chiapetto, M. [SCK-CEN, Nuclear Materials Science Institute, Mol (Belgium); Unite Materiaux et Transformations (UMET), UMR 8207, Universite de Lille 1, ENSCL, Villeneuve d' Ascq (France); Becquart, C.S. [Unite Materiaux et Transformations (UMET), UMR 8207, Universite de Lille 1, ENSCL, Villeneuve d' Ascq (France); Laboratoire commun EDF-CNRS, Etude et Modelisation des Microstructures pour le Vieillissement des Materiaux (EM2VM) (France); Domain, C. [EDF R and D, Departement Materiaux et Mecanique des Composants, Les Renardieres, Moret sur Loing (France); Laboratoire commun EDF-CNRS, Etude et Modelisation des Microstructures pour le Vieillissement des Materiaux (EM2VM) (France); Malerba, L. [SCK-CEN, Nuclear Materials Science Institute, Mol (Belgium)

    2015-01-01

    Post-irradiation annealing experiments are often used to obtain clearer information on the nature of defects produced by irradiation. However, their interpretation is not always straightforward without the support of physical models. We apply here a physically-based set of parameters for object kinetic Monte Carlo (OKMC) simulations of the nanostructural evolution of FeMnNi alloys under irradiation to the simulation of their post-irradiation isochronal annealing, from 290 to 600 C. The model adopts a ''grey alloy'' scheme, i.e. the solute atoms are not introduced explicitly, only their effect on the properties of point-defect clusters is. Namely, it is assumed that both vacancy and SIA clusters are significantly slowed down by the solutes. The slowing down increases with size until the clusters become immobile. Specifically, the slowing down of SIA clusters by Mn and Ni can be justified in terms of the interaction between these atoms and crowdions in Fe. The results of the model compare quantitatively well with post-irradiation isochronal annealing experimental data, providing clear insight into the mechanisms that determine the disappearance or re-arrangement of defects as functions of annealing time and temperature. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Kinetic Monte Carlo simulation of nanostructural evolution under post-irradiation annealing in dilute FeMnNi

    International Nuclear Information System (INIS)

    Post-irradiation annealing experiments are often used to obtain clearer information on the nature of defects produced by irradiation. However, their interpretation is not always straightforward without the support of physical models. We apply here a physically-based set of parameters for object kinetic Monte Carlo (OKMC) simulations of the nanostructural evolution of FeMnNi alloys under irradiation to the simulation of their post-irradiation isochronal annealing, from 290 to 600 C. The model adopts a ''grey alloy'' scheme, i.e. the solute atoms are not introduced explicitly, only their effect on the properties of point-defect clusters is. Namely, it is assumed that both vacancy and SIA clusters are significantly slowed down by the solutes. The slowing down increases with size until the clusters become immobile. Specifically, the slowing down of SIA clusters by Mn and Ni can be justified in terms of the interaction between these atoms and crowdions in Fe. The results of the model compare quantitatively well with post-irradiation isochronal annealing experimental data, providing clear insight into the mechanisms that determine the disappearance or re-arrangement of defects as functions of annealing time and temperature. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. Emittance dilution through coherent energy spread generation in bending systems

    International Nuclear Information System (INIS)

    For a bunched beam, coherent energy spread generated within a bending system may couple to the transverse (bending) plane coordinates through the chromatic transfer functions of the particular beamline - even an achromatic beamline. The resulting transverse emittance dilution is dependent on the magnitude of the energy spread, its generation rate along the beamline, and the beamline's chromatic transfer functions. The coherent energy spread may be due to resistive-wall wakefields or coherent synchrotron radiation. For specific beamlines, such as a periodic arc or wiggler, the longitudinal-to-transverse coupling is minimal and, in ideal cases, completely suppressed resulting in reduction or cancellation of all transverse emittance dilution effects. This is of particular interest for micro-bunch transport or compression systems such as exist in future FEL or linear collider projects

  15. Effects of high-temperature diluted-H2 annealing on effective mobility of 4H-SiC MOSFETs with thermally-grown SiO2

    Science.gov (United States)

    Hirai, Hirohisa; Kita, Koji

    2016-04-01

    The impact of post-oxidation annealing (POA) in diluted-H2 ambient on a 4H-SiC/SiO2 interface was investigated with a cold wall furnace. Effective mobility (μeff) was extracted from lateral metal-oxide-semiconductor field-effect transistors (MOSFETs) by applying the split capacitance-voltage (C-V) technique to the determination of charge density and a calibration technique using two MOSFETs with different gate lengths to minimize the contribution of parasitic components. POA at 1150 °C in diluted-H2 ambient resulted in an enhancement of μeff compared with that for POA in N2 ambient. It was indicated that the effects of POA in diluted H2 should be attributed to the reduction in the density of near interface traps, which disturb the electron transportation in the inversion channel, from the measurement temperature dependence of μeff as well as from the C-V curves of MOS capacitors fabricated on n-type SiC.

  16. Transfer-matrix scaling for diluted Ising systems

    Science.gov (United States)

    de Queiroz, S. L. A.; Stinchcombe, R. B.

    1992-09-01

    A transfer-matrix scaling technique is developed for randomly diluted systems and applied to the site-diluted Ising model on a square lattice. For each connected configuration between adjacent columns, the contribution of the respective transfer matrix to the decay of correlations is considered only as far as the ratio of the two largest eigenvalues, allowing an economical incorporation of configurational averages. Predictions for the phase boundary at and near the percolation and pure Ising limits, and for the correlation exponent η at those limits, agree with exactly known results to within 1% error with largest strip widths of only L=5. The exponent η remains near the pure value (1/4) for all intermediate concentrations until it turns over to the percolation value at the threshold.

  17. Quantum Annealing and Quantum Fluctuation Effect in Frustrated Ising Systems

    OpenAIRE

    Tanaka, Shu; Tamura, Ryo

    2012-01-01

    Quantum annealing method has been widely attracted attention in statistical physics and information science since it is expected to be a powerful method to obtain the best solution of optimization problem as well as simulated annealing. The quantum annealing method was incubated in quantum statistical physics. This is an alternative method of the simulated annealing which is well-adopted for many optimization problems. In the simulated annealing, we obtain a solution of optimization problem b...

  18. Microscopic Properties of Quantum Annealing -- Application to Fully Frustrated Ising Systems

    OpenAIRE

    Tanaka, Shu

    2011-01-01

    In this paper we show quantum fluctuation effect of fully frustrated Ising spin systems. Quantum annealing has been expected to be an efficient method to find ground state of optimization problems. However it is not clear when to use the quantum annealing. In order to clarify when the quantum annealing works well, we have to study microscopic properties of quantum annealing. In fully frustrated Ising spin systems, there are macroscopically degenerated ground states. When we apply quantum anne...

  19. Quantum Annealing Effect on Entropic Slowing Down in Frustrated Decorated Bond System

    OpenAIRE

    Tanaka, Shu; Miyashita, Seiji

    2006-01-01

    We propose that the importance of the quantum annealing procedure to find the ground state of frustrated decorated bond systems where 'entropic slowing down' happens due to peculiar density of states. Here, we use the time dependent Schr\\"odinger equation to analyze the real time dynamics of the process. It is found that the quantum annealing is very efficient comparing to the thermal annealing for searching the ground state of the systems. We analyze the mechanism of quantum annealing from a...

  20. Automated spike preparation system for Isotope Dilution Mass Spectrometry (IDMS)

    International Nuclear Information System (INIS)

    Isotope Dilution Mass Spectrometry (IDMS) is a method frequently employed to measure dissolved, irradiated nuclear materials. A known quantity of a unique isotope of the element to be measured (referred to as the ''spike'') is added to the solution containing the analyte. The resulting solution is chemically purified then analyzed by mass spectrometry. By measuring the magnitude of the response for each isotope and the response for the ''unique spike'' then relating this to the known quantity of the ''spike'', the quantity of the nuclear material can be determined. An automated spike preparation system was developed at the Savannah River Site (SRS) to dispense spikes for use in IDMS analytical methods. Prior to this development, technicians weighed each individual spike manually to achieve the accuracy required. This procedure was time-consuming and subjected the master stock solution to evaporation. The new system employs a high precision SMI Model 300 Unipump dispenser interfaced with an electronic balance and a portable Epson HX-20 notebook computer to automate spike preparation

  1. Time series forecasting using a TSK fuzzy system tuned with simulated annealing

    OpenAIRE

    Almaraashi, Majid; John, Robert; Coupland, Simon; Hopgood, Adrian

    2010-01-01

    In this paper, a combination of a Takagi-Sugeno fuzzy system (TSK) and simulated annealing is used to predict well known time series by searching for the best configuration of the fuzzy system. Simulated annealing is used to optimise the parameters of the antecedent and the consequent parts of the fuzzy system rules. The results of the proposed method are encouraging indicating that simulated annealing and fuzzy logic are able to combine well in time series prediction.

  2. Cold, dilute, trapped bosons as an open quantum system

    OpenAIRE

    Anglin, James

    1996-01-01

    We present a master equation governing the reduced density operator for a single trapped mode of a cold, dilute, weakly interacting Bose gas; and we obtain an operator fluctuation-dissipation relation in which the Ginzburg-Landau effective potential plays a physically transparent role. We also identify a decoherence effect that tends to preserve symmetry, even when the effective potential has a ``Mexican hat'' form.

  3. Annealing effect on current perpendicular to plane systems modeled by giant magnetoresistance simulation

    NARCIS (Netherlands)

    Jonkers, PAE

    2001-01-01

    A simulation single-electron model is presented to describe the effect of annealing current perpendicular to plane-giant magnetoresistance (CPP-GMR) systems. Progressive annealing is represented by a progressively increasing number of impurities occurring at the interfaces of adjacent layers constit

  4. ACTIVITY-BASED COSTING DAN SIMULATED ANNEALING UNTUK PENCARIAN RUTE PADA FLEXIBLE MANUFACTURING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Gregorius Satia Budhi

    2003-01-01

    Full Text Available Flexible Manufacturing System (FMS is a manufacturing system that is formed from several Numerical Controlled Machines combine with material handling system, so that different jobs can be worked by different machines sequences. FMS combine the high productivity and flexibility of Transfer Line and Job Shop manufacturing system. In this reasearch, Activity-Based Costing(ABC approach was used as the weight to search the operation route in the proper machine, so that the total production cost can be optimized. The search method that was used in this experiment is Simulated Annealling, a variant form Hill Climbing Search method. An ideal operation time to proses a part was used as the annealling schedule. From the empirical test, it could be proved that the use of ABC approach and Simulated Annealing to search the route (routing process can optimize the Total Production Cost. In the other hand, the use of ideal operation time to process a part as annealing schedule can control the processing time well. Abstract in Bahasa Indonesia : Flexible Manufacturing System (FMS adalah sistem manufaktur yang tersusun dari mesin-mesin Numerical Control (NC yang dikombinasi dengan Sistem Penanganan Material, sehingga job-job berbeda dikerjakan oleh mesin-mesin dengan alur yang berlainan. FMS menggabungkan produktifitas dan fleksibilitas yang tinggi dari Sistem Manufaktur Transfer Line dan Job Shop. Pada riset ini pendekatan Activity-Based Costing (ABC digunakan sebagai bobot / weight dalam pencarian rute operasi pada mesin yang tepat, untuk lebih mengoptimasi biaya produksi secara keseluruhan. Adapun metode Searching yang digunakan adalah Simulated Annealing yang merupakan varian dari metode searching Hill Climbing. Waktu operasi ideal untuk memproses sebuah part digunakan sebagai Annealing Schedulenya. Dari hasil pengujian empiris dapat dibuktikan bahwa penggunaan pendekatan ABC dan Simulated Annealing untuk proses pencarian rute (routing dapat lebih

  5. Transfer-matrix scaling from disorder-averaged correlation lengths for diluted Ising systems

    OpenAIRE

    de Queiroz, S. L. A.; Stinchcombe, R. B.

    1994-01-01

    A transfer matrix scaling technique is developed for randomly diluted systems, and applied to the site-diluted Ising model on a square lattice in two dimensions. For each allowed disorder configuration between two adjacent columns, the contribution of the respective transfer matrix to the decay of correlations is considered only as far as the ratio of its two largest eigenvalues, allowing an economical calculation of a configuration-averaged correlation length. Standard phenomenological-renor...

  6. Application of multi-singlechip based on radioactive reagent diluting and dividing system

    International Nuclear Information System (INIS)

    The radioactive reagent diluting and dividing system exchanges information with human by using LCD screen and keyboard. Five high precision step-motors are used to make the mechanical arm with two injectors moving to three-dimensional location, and control the inhalation volume of the two injectors. There are six singlechips in this system. All of the singlechips are united to a cooperative system by serial-bus. This system can be used to divide and dilute the radioactive reagent with high precision and no contamination. (authors)

  7. Development of a constant dilution sampling system for particulate and gaseous pollutant measurements

    International Nuclear Information System (INIS)

    This paper presents a new concept of a partial flow sampling system (PFSS), involving a two-stage diluter which operates on the principle of underpressure, while exhaust is sampled through a capillary. Due to the low flowrate through the capillary, the diluter may be sampling from a freely exhausting tailpipe and is not prone to pressure variations in the exhaust line. In addition, the PFSS operates at constant pressure conditions even upstream of diesel particle filters that increase the backpressure in the tailpipe. As a result, the PFSS offers a constant dilution ratio (DR) over any engine or vehicle operation condition. This study presents the diluter concept and a straightforward model developed to calculate the DR, depending on the dilution air flowrate and the diluter underpressure. The model is validated using CO2 as a trace gas, and very good agreement is demonstrated between the calculated and the measured DR values. Following validation, the PFSS is combined with aerosol measurement instruments to measure the exhaust particle concentration of a diesel engine operating at different steady-state modes. For demonstrating the stability of the DR and applicability of the PFSS, measurements are conducted with both heavy duty and light duty diesel exhaust gases. Future applications of this device include gas and particle exhaust measurements both in laboratory environments and on-board vehicles. (paper)

  8. Reorganization Law and Dilution Threats in Different Financial Systems

    NARCIS (Netherlands)

    Hege, U.; Mella-Barral, P.

    2000-01-01

    In a market-based financial system, credit is held by dispersed creditors, and out-of-court renegotiation of debt is more likely to fail because of hold-out problems; in a bank-based system, out-of-court renegotiation stands good chances to succeed. Since out-of-court renegotiation is a substitute f

  9. Dielectric relaxation in weakly ergodic dilute dipole systems.

    Science.gov (United States)

    Lerner, Shimon E; Mierzwa, Michal; Paluch, Marian; Feldman, Yuri; Ishai, Paul Ben

    2013-05-28

    We introduce a method for calculating dipole correlations in systems containing hopping processes exhibiting weak ergodicity breaking. Modeled after the original Kirkwood-Fröhlich theory, the new method provides a bridge extending Fröhlich's insights from the realm of rigid dipoles into weakly non-ergodic fluctuating virtual dipolar entities. Relevant for the investigation of any system containing transport processes, it provides a testable parameter derived primarily from the static dielectric parameters. Three examples of systems including porous silicon, porous glass, and ferroelectric crystals are brought to demonstrate the model's versatility, including direct confirmation of Fröhlich's original idea. PMID:23742487

  10. Surface tension of liquid dilute solutions of lead-cesium and bismuth-cesium systems

    International Nuclear Information System (INIS)

    Method of the maximal pressure in a drop was used to measure the surface tension of 15 liquid dilute solutions of lead-cesium system in 0-0.214 at% concentration range and of 12 diluted solutions of bismuth-cesium system in 0-0.160 at.% cesium range from solidification temperature up to 500 dec C. It was found that cesium was characterized as surfactant in lead and bismuth melts. It was established that the temperature coefficient of surface tension changes sufficiently in maximally diluted solutions of alkali metals in bismuth and lead melts. Effect of sodium, potassium, rubidum and cesium on the value of surface tension of lead and bismuth was systematized. Growth of activity in sodium, potassium, rubidium and cesium series was noted

  11. Simulated annealing versus quantum annealing

    Science.gov (United States)

    Troyer, Matthias

    Based on simulated classical annealing and simulated quantum annealing using quantum Monte Carlo (QMC) simulations I will explore the question where physical or simulated quantum annealers may outperform classical optimization algorithms. Although the stochastic dynamics of QMC simulations is not the same as the unitary dynamics of a quantum system, I will first show that for the problem of quantum tunneling between two local minima both QMC simulations and a physical system exhibit the same scaling of tunneling times with barrier height. The scaling in both cases is O (Δ2) , where Δ is the tunneling splitting. An important consequence is that QMC simulations can be used to predict the performance of a quantum annealer for tunneling through a barrier. Furthermore, by using open instead of periodic boundary conditions in imaginary time, equivalent to a projector QMC algorithm, one obtains a quadratic speedup for QMC, and achieve linear scaling in Δ. I will then address the apparent contradiction between experiments on a D-Wave 2 system that failed to see evidence of quantum speedup and previous QMC results that indicated an advantage of quantum annealing over classical annealing for spin glasses. We find that this contradiction is resolved by taking the continuous time limit in the QMC simulations which then agree with the experimentally observed behavior and show no speedup for 2D spin glasses. However, QMC simulations with large time steps gain further advantage: they ``cheat'' by ignoring what happens during a (large) time step, and can thus outperform both simulated quantum annealers and classical annealers. I will then address the question how to optimally run a simulated or physical quantum annealer. Investigating the behavior of the tails of the distribution of runtimes for very hard instances we find that adiabatically slow annealing is far from optimal. On the contrary, many repeated relatively fast annealing runs can be orders of magnitude faster for

  12. Long-range interactions in dilute granular systems

    NARCIS (Netherlands)

    Müller, Micha-Klaus

    2008-01-01

    In this thesis, on purpose, we focussed on the most challenging, longest ranging potentials. We analyzed granular media of low densities obeying 1/r long-range interaction potentials between the granules. Such systems are termed granular gases and differ in their behavior from ordinary gases by diss

  13. 33 CFR 154.824 - Inerting, enriching, and diluting systems.

    Science.gov (United States)

    2010-07-01

    ... the facility vapor connection that ensures complete mixing of the gases within 20 pipe diameters of... oxygen concentration in the vapor collection line exceeds 9.0 percent by volume; and (4) If a combustion... combustion device and the vapor collection line. (i) An enriching system must: (1) Supply...

  14. Effect of annealing on phase sequence and their composition in the Pt-coated Mo system

    Energy Technology Data Exchange (ETDEWEB)

    Khumalo, Z.M., E-mail: zakhele@tlabs.ac.za [Department of Physics, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Topić, M. [Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Comrie, C.M. [Department of Physics, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Blumenthal, M. [Department of Physics, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Pineda-Vargas, C.A.; Bucher, R. [Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Kisslinger, K. [Center for Functional Nanomaterials, Brookhaven National Laboratory, P.O. Box 5000, Upton, NY USA (United States)

    2014-11-01

    Highlights: • Platinum coatings were prepared using electron beam evaporator. • The phase analysis revealed the presence of the MoPt{sub 2} and MoPt. • At low annealing time, the MoPt{sub 2} phase appeared to have more Pt content. • The MoPt{sub 2} phase disappeared as the annealing time increases. • It is believed that the MoPt phase was growing at the expense of the MoPt{sub 2}. - Abstract: The phase formation sequence and the composition of phases induced by thermal annealing in a platinum (Pt) coated molybdenum (Mo) system were investigated by X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS) and transmission electron microscopy (TEM). The X-ray diffraction study of a 0.2 μm thick platinum layer deposited on a Mo substrate and annealed at temperatures between 800 °C and 900 °C for different periods of time shows the formation of MoPt{sub 2} and MoPt phases. It was also found that these phases nucleate sequentially and the MoPt{sub 2} phase becomes unstable at 900 °C after a longer annealing time of 8 h. Rutherford backscattering spectroscopy and transmission electron microscopy showed that the coating thickness approximately doubled after thermal annealing, from 0.22 μm to 0.46 μm, due to the formation of the Pt–Mo phases.

  15. Effect of annealing on phase sequence and their composition in the Pt-coated Mo system

    International Nuclear Information System (INIS)

    Highlights: • Platinum coatings were prepared using electron beam evaporator. • The phase analysis revealed the presence of the MoPt2 and MoPt. • At low annealing time, the MoPt2 phase appeared to have more Pt content. • The MoPt2 phase disappeared as the annealing time increases. • It is believed that the MoPt phase was growing at the expense of the MoPt2. - Abstract: The phase formation sequence and the composition of phases induced by thermal annealing in a platinum (Pt) coated molybdenum (Mo) system were investigated by X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS) and transmission electron microscopy (TEM). The X-ray diffraction study of a 0.2 μm thick platinum layer deposited on a Mo substrate and annealed at temperatures between 800 °C and 900 °C for different periods of time shows the formation of MoPt2 and MoPt phases. It was also found that these phases nucleate sequentially and the MoPt2 phase becomes unstable at 900 °C after a longer annealing time of 8 h. Rutherford backscattering spectroscopy and transmission electron microscopy showed that the coating thickness approximately doubled after thermal annealing, from 0.22 μm to 0.46 μm, due to the formation of the Pt–Mo phases

  16. Vapor–Liquid Equilibrium in Diluted Polymer + Toluene Systems

    Czech Academy of Sciences Publication Activity Database

    Bogdanić, Grozdana; Wichterle, Ivan

    Praha: Česká společnost chemického inženýrství, 2011 - (Halfar, R.), s. 149 ISBN 978-80-905035-0-2. [Konference chemického a procesního inženýrství CHISA 2011 /58./. Srní, Šumava (CZ), 24.10.2011-27.10.2011] R&D Projects: GA ČR GA104/07/0444 Institutional research plan: CEZ:AV0Z40720504 Keywords : polymer and toluene systems * experimental data * vapor–liquid equilibrium data Subject RIV: CF - Physical ; Theoretical Chemistry www.chisa.cz/2011

  17. MOBILE SYSTEMS FOR DILUTION OF HIGHLY ENRICHED URANIUM AND URANIUM CONTAINING COMPONENTS

    Energy Technology Data Exchange (ETDEWEB)

    Adams, T

    2007-05-02

    A mobile melt-dilute (MMD) module for the treatment of aluminum research reactor spent fuel is being developed. The process utilizes a closed system approach to retain fission products/gases inside a sealed canister after treatment. The MMD process melts and dilutes spent fuel with depleted uranium to obtain a fissile fraction of less than 0.2. The final ingot is solidified inside the sealed canister and can be stored safely either wet or dry until final disposition or reprocessing. The MMD module can be staged at or near the research reactor fuel storage sites to facilitate the melt-dilute treatment of the spent fuel into a stable non-proliferable form.

  18. Open-System Quantum Annealing in Mean-Field Models with Exponential Degeneracy*

    Science.gov (United States)

    Kechedzhi, Kostyantyn; Smelyanskiy, Vadim N.

    2016-04-01

    Real-life quantum computers are inevitably affected by intrinsic noise resulting in dissipative nonunitary dynamics realized by these devices. We consider an open-system quantum annealing algorithm optimized for such a realistic analog quantum device which takes advantage of noise-induced thermalization and relies on incoherent quantum tunneling at finite temperature. We theoretically analyze the performance of this algorithm considering a p -spin model that allows for a mean-field quasiclassical solution and, at the same time, demonstrates the first-order phase transition and exponential degeneracy of states, typical characteristics of spin glasses. We demonstrate that finite-temperature effects introduced by the noise are particularly important for the dynamics in the presence of the exponential degeneracy of metastable states. We determine the optimal regime of the open-system quantum annealing algorithm for this model and find that it can outperform simulated annealing in a range of parameters. Large-scale multiqubit quantum tunneling is instrumental for the quantum speedup in this model, which is possible because of the unusual nonmonotonous temperature dependence of the quantum-tunneling action in this model, where the most efficient transition rate corresponds to zero temperature. This model calculation is the first analytically tractable example where open-system quantum annealing algorithm outperforms simulated annealing, which can, in principle, be realized using an analog quantum computer.

  19. Atomic diffusion in annealed CU/SiO2/Si (100) system prepared by magnetron sputtering

    International Nuclear Information System (INIS)

    Cu thin films are deposited on p-type Si (100) substrates by magnetron sputtering at room temperature. The interface reaction and atomic diffusion of Cu/SiO2/Si (100) systems are studied by x-ray diffraction (XRD) and Rutherford backscattering spectrometry (RBS). Some significant results can be obtained. The onset temperature of interdiffusion for Cu/SiO2/Si(100) is 350 °C. With the annealing temperature increasing, the interdiffusion becomes more apparent. The calculated diffusion activation energy is about 0.91 eV. For the CU/SiO2/Si (100) systems copper silicides are not formed below an annealing temperature of 350 °C. The formation of the copper silicides phase is observed when the annealing temperature arrives at 450 °C. (condensed matter: structure, thermal and mechanical properties)

  20. Pure and dilute Z(N) spin and generalized gauge lattice systems: duality and related conjectures

    International Nuclear Information System (INIS)

    By generalizing recently introduced quantities (referred to as 'thermal transmissivities'), the usual duality results concerning the pure Z(N) spin systems (including the standard Ising and Potts models) are recovered as well as generalized gauge systems (plaquettes or more complex simplex) in d- dimensional hypercubic lattices. The essential relationship between duality and simple series-parallel transformation becomes evident. The simplicity of the equations enables conjectures on the approximate critical frontier of the diluted version of the above systems, including some particular asymptotic behaviours which are believed to be exact. As an illustration the d = 2 diluted Z(4) spin system is discussed in some detail: for those regions where exact results are available the agreement is satisfactory. (Author)

  1. Dynamical scaling and crossover from algebraic to logarithmic growth in dilute systems

    DEFF Research Database (Denmark)

    Mouritsen, Ole G.; Shah, Peter Jivan

    1989-01-01

    The ordering dynamics of the two-dimensional Ising antiferromagnet with mobile vacancies and nonconserved order parameter is studied by Monte Carlo temperature-quenching experiments. The domain-size distribution function is shown to obey dynamical scaling. A crossover is found from an algebraic g...... growth law for the pure system to effectively logarithmic growth behavior in the dilute system, in accordance with recent experiments on ordering kinetics in impure chemisorbed overlayers and off-stoichiometric alloys....

  2. Effect of annealing on superconductivity in Fe1+y(Te1-xSx) system

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    We have synthesized polycrystalline samples of Fe1.11(Te1-xSx) and single crystals of Fe1+y(Te0.88S0.12),and characterized their properties.Our results show that the solid solution of S in the Fe1.11Te tetragonal lattice is limited,~10%.We observed superconductivity at ~8 K in both polycrystalline samples and single crystals.Magnetization measurements reveal that the volume fraction is small for this superconducting phase in both polycrystalline samples as-synthesized and single crystals as-grown.It is found that annealing in air enhances the superconducting fraction;the maximum fraction is almost 100% in the single crystals annealed in air at 300°C.We discuss the effect of annealing on superconductivity and transport properties at the normal state in the Fe1+y(Te1-xSx) system in terms of decrease of the excess Fe.

  3. Multivariable Optimization: Quantum Annealing & Computation

    OpenAIRE

    Mukherjee, Sudip; Chakrabarti, Bikas K.

    2014-01-01

    Recent developments in quantum annealing techniques have been indicating potential advantage of quantum annealing for solving NP-hard optimization problems. In this article we briefly indicate and discuss the beneficial features of quantum annealing techniques and compare them with those of simulated annealing techniques. We then briefly discuss the quantum annealing studies of some model spin glass and kinetically constrained systems.

  4. Prediction of two-dimensional diluted magnetic semiconductors: Doped monolayer MoS2 systems

    KAUST Repository

    Cheng, Yingchun

    2013-03-05

    Using first-principles calculations, we propose a two-dimensional diluted magnetic semiconductor: monolayer MoS2 doped by transition metals. Doping of transition metal atoms from the IIIB to VIB groups results in nonmagnetic states, since the number of valence electrons is smaller or equal to that of Mo. Doping of atoms from the VIIB to IIB groups becomes energetically less and less favorable. Magnetism is observed for Mn, Fe, Co, Zn, Cd, and Hg doping, while for the other dopants from these groups it is suppressed by Jahn-Teller distortions. Analysis of the binding energies and magnetic properties indicates that (Mo,X)S2 (X=Mn, Fe, Co, and Zn) are promising systems to explore two-dimensional diluted magnetic semiconductors.

  5. The Parameters Optimization of MCR-WPT System Based on the Improved Genetic Simulated Annealing Algorithm

    Directory of Open Access Journals (Sweden)

    Sheng Lu

    2015-01-01

    Full Text Available To solve the problem of parameter selection during the design of magnetically coupled resonant wireless power transmission system (MCR-WPT, this paper proposed an improved genetic simulated annealing algorithm. Firstly, the equivalent circuit of the system is analysis in this study and a nonlinear programming mathematical model is built. Secondly, in place of the penalty function method in the genetic algorithm, the selection strategy based on the distance between individuals is adopted to select individual. In this way, it reduces the excess empirical parameters. Meanwhile, it can improve the convergence rate and the searching ability by calculating crossover probability and mutation probability according to the variance of population’s fitness. At last, the simulated annealing operator is added to increase local search ability of the method. The simulation shows that the improved method can break the limit of the local optimum solution and get the global optimum solution faster. The optimized system can achieve the practical requirements.

  6. Network Reconfiguration for Reliability Worth Enhancement in Distribution Systems by Simulated Annealing

    OpenAIRE

    Sirisumrannukul, Somporn

    2010-01-01

    The network reconfiguration problem for reliability enhancement is solved by the developed simulated annealing in conjunction with reliability worth analysis that provides an indirect measure for cost implication associated with power failure. The objective is to minimize customer interruption cost with the constraints that all load points have to be electrically supplied and radially connected. It can be seen from the results of the RBTS and the 69-bus system that the total customer interrup...

  7. Parameter estimation for chaotic systems using a hybrid adaptive cuckoo search with simulated annealing algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Zheng, E-mail: 19994035@sina.com [College of Meteorology and Oceanography, PLA University of Science and Technology, Nanjing 211101 (China); Wang, Jun; Zhou, Bihua [National Defense Key Laboratory on Lightning Protection and Electromagnetic Camouflage, PLA University of Science and Technology, Nanjing 210007 (China); Zhou, Shudao [College of Meteorology and Oceanography, PLA University of Science and Technology, Nanjing 211101 (China); Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science and Technology, Nanjing 210044 (China)

    2014-03-15

    This paper introduces a novel hybrid optimization algorithm to establish the parameters of chaotic systems. In order to deal with the weaknesses of the traditional cuckoo search algorithm, the proposed adaptive cuckoo search with simulated annealing algorithm is presented, which incorporates the adaptive parameters adjusting operation and the simulated annealing operation in the cuckoo search algorithm. Normally, the parameters of the cuckoo search algorithm are kept constant that may result in decreasing the efficiency of the algorithm. For the purpose of balancing and enhancing the accuracy and convergence rate of the cuckoo search algorithm, the adaptive operation is presented to tune the parameters properly. Besides, the local search capability of cuckoo search algorithm is relatively weak that may decrease the quality of optimization. So the simulated annealing operation is merged into the cuckoo search algorithm to enhance the local search ability and improve the accuracy and reliability of the results. The functionality of the proposed hybrid algorithm is investigated through the Lorenz chaotic system under the noiseless and noise condition, respectively. The numerical results demonstrate that the method can estimate parameters efficiently and accurately in the noiseless and noise condition. Finally, the results are compared with the traditional cuckoo search algorithm, genetic algorithm, and particle swarm optimization algorithm. Simulation results demonstrate the effectiveness and superior performance of the proposed algorithm.

  8. Parameter estimation for chaotic systems using a hybrid adaptive cuckoo search with simulated annealing algorithm

    Science.gov (United States)

    Sheng, Zheng; Wang, Jun; Zhou, Shudao; Zhou, Bihua

    2014-03-01

    This paper introduces a novel hybrid optimization algorithm to establish the parameters of chaotic systems. In order to deal with the weaknesses of the traditional cuckoo search algorithm, the proposed adaptive cuckoo search with simulated annealing algorithm is presented, which incorporates the adaptive parameters adjusting operation and the simulated annealing operation in the cuckoo search algorithm. Normally, the parameters of the cuckoo search algorithm are kept constant that may result in decreasing the efficiency of the algorithm. For the purpose of balancing and enhancing the accuracy and convergence rate of the cuckoo search algorithm, the adaptive operation is presented to tune the parameters properly. Besides, the local search capability of cuckoo search algorithm is relatively weak that may decrease the quality of optimization. So the simulated annealing operation is merged into the cuckoo search algorithm to enhance the local search ability and improve the accuracy and reliability of the results. The functionality of the proposed hybrid algorithm is investigated through the Lorenz chaotic system under the noiseless and noise condition, respectively. The numerical results demonstrate that the method can estimate parameters efficiently and accurately in the noiseless and noise condition. Finally, the results are compared with the traditional cuckoo search algorithm, genetic algorithm, and particle swarm optimization algorithm. Simulation results demonstrate the effectiveness and superior performance of the proposed algorithm.

  9. Insertable system for fast turnaround time microwave experiments in a dilution refrigerator.

    Science.gov (United States)

    Ong, Florian R; Orgiazzi, Jean-Luc; de Waard, Arlette; Frossati, Giorgio; Lupascu, Adrian

    2012-09-01

    Microwave experiments in dilution refrigerators are a central tool in the field of superconducting quantum circuits and other research areas. This type of experiments relied so far on attaching a device to the mixing chamber of a dilution refrigerator. The minimum turnaround time in this case is a few days as required by cooling down and warming up the entire refrigerator. We developed a new approach, in which a suitable sample holder is attached to a cold-insertable probe and brought in contact with transmission lines permanently mounted inside the cryostat. The total turnaround time is 8 h if the target temperature is 80 mK. The lowest attainable temperature is 30 mK. Our system can accommodate up to six transmission lines, with a measurement bandwidth tested from zero frequency to 12 GHz. This bandwidth is limited by low-pass components in the setup; we expect the intrinsic bandwidth to be at least 18 GHz. We present our setup, discuss the experimental procedure, and give examples of experiments enabled by this system. This new measurement method will have a major impact on systematic ultra-low temperature studies using microwave signals, including those requiring quantum coherence. PMID:23020391

  10. Transfer-matrix scaling from disorder-averaged correlation lengths for diluted Ising systems

    Science.gov (United States)

    de Queiroz, S. L. A.; Stinchcombe, R. B.

    1994-10-01

    A transfer-matrix-scaling technique is developed for randomly diluted systems, and applied to the site-diluted Ising model on a square lattice in two dimensions. For each allowed disorder configuration between two adjacent columns, the contribution of the respective transfer matrix to the decay of correlations is considered only as far as the ratio of its two largest eigenvalues, allowing an economical calculation of a configuration-averaged correlation length. Standard phenomenological-renormalization procedures are then used to analyze aspects of the phase boundary which are difficult to assess accurately by alternative methods. For magnetic site concentration p close to pc, the extent of exponential behavior of the Tc×p curve is clearly seen for over two decades of variation of p-pc. Close to the pure-system limit, the exactly known reduced slope is reproduced to a very good approximation, though with nonmonotonic convergence. The averaged correlation lengths are inserted into the exponent-amplitude relationship predicted by conformal invariance to hold at criticality. The resulting exponent η remains near the pure value (1/4) for all intermediate concentrations until it crosses over to the percolation value at the threshold.

  11. Cyclic Heating-Annealing and Boltzmann Distribution of Free Energies in a Spin-Glass System

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hai-Jun

    2007-01-01

    Ergodicity of a spin-glass is broken at low temperatures; the system is trapped in one of many ergodic configurational domains. Transitions between different ergodic domains are achievable through a heating-annealing procedure. If this experiment is repeated infinite times, all ergodic configurational domains will be visited with frequences that decreasing exponentially with their free energies. The mean free energy density of a spin-glass system on a random graph is calculated based on this free energy Boltzmann distribution in the present work, by means of the cavity approach.

  12. A cryogen-free dilution refrigerator based Josephson qubit measurement system.

    Science.gov (United States)

    Tian, Ye; Yu, H F; Deng, H; Xue, G M; Liu, D T; Ren, Y F; Chen, G H; Zheng, D N; Jing, X N; Lu, Li; Zhao, S P; Han, Siyuan

    2012-03-01

    We develop a small-signal measurement system on cryogen-free dilution refrigerator which is suitable for superconducting qubit studies. Cryogen-free refrigerators have several advantages such as less manpower for system operation and large sample space for experiment, but concern remains about whether the noise introduced by the coldhead can be made sufficiently low. In this work, we demonstrate some effective approaches of acoustic isolation to reduce the noise impact. The electronic circuit that includes the current, voltage, and microwave lines for qubit coherent state measurement is described. For the current and voltage lines designed to have a low pass of dc-100 kHz, we show that the measurements of Josephson junction's switching current distribution with a width down to 1 nA, and quantum coherent Rabi oscillation and Ramsey interference of the superconducting qubit can be successfully performed. PMID:22462938

  13. 119Sn Moessbauer spectroscopy in the magnetically diluted Heusler-type systems

    International Nuclear Information System (INIS)

    119Sn Moessbauer investigations of the ferromagnetically diluted Nisub(2)Mnsub(x)Bsub(1-x)Sn(B=Ti, V) and Pdsub(2)Mnsub(x)Vsub(1-x)Sn Heusler-type systems have been performed and the results are reviewed and discussed. It has been found that distributions of the transferred hyperfine magnetic field as seen by a tin nucleus are very sensitive for a type of the local magnetic interaction in these simple ferromagnets, especially when studied versus the sample temperature. This sensitivity allows to reach some conclusions about the coupling mechanism between localised manganese magnetic moments. Namely, it is concluded that the interaction beyond the second neighbour shell is practically irrelevant for the magnetic ordering process. This very fact means that the free electron approach to the calculation of exchange integrals can not be applied for these particular systems. (Author)

  14. Pure and diluted contrast medium in the evaluation of portal venous system with digital subtraction angiography

    International Nuclear Information System (INIS)

    We report the results of intra-arterial digital subtraction angiography (DSA) in 100 patients with portal hypertension. The portal venous system was evaluated; all patients underwent angiography of the celiac and superior mesenteric arteries before surgery. Forty-four of them were also examined after Warren splenorenal shunts. Therefore, a total of 144 exams was evaluated. The authors always employed low-osmolality ionic and non-ionic contrast media (iodine concentration: 300-350 mg/ml). In 70 cases pure contrast medium was injected (20/25 ml): in the extant 74 cases it was diluted with an equal volume of saline solution (osmolality and iodine concentration reduced by 50%). Intra-arterial DSA always visualized portal venous system, collateral circulation, shunt location and postoperative changes. The mayor advantage of intra-arterial DSA is the smaller amount of contrast medium injected, so that local and systemic side effects are rare. According to our experience, it is best to dilute the contrast medium and inject the same amount as in conventional angiography, at the same rate. Other well-known advantages of intra-arterial DSA are quicker execution, less injury to arteries using smaller caliber catheters, and low cost. The major disadvantage of intra-arterial DSA, as it appeared also in our study, is the field size of the intensifier, which in our case was limited to 6-9 inches. This is an insufficient coverage for the whole portal system to be studied, and some contrast medium injections become therefore necessary. An average of 3 injections were given to each patient. This problem reduces the advantage of less contrast medium per injection. At any rate, even though intra-arterial DSA exhibits this limitation, it can nevertheless yield important information in the pre- and postoperative evaluation of patients with portal hypertension

  15. Nonequilibrium spin transport through a diluted magnetic semiconductor quantum dot system with noncollinear magnetization

    International Nuclear Information System (INIS)

    The spin-dependent transport through a diluted magnetic semiconductor quantum dot (QD) which is coupled via magnetic tunnel junctions to two ferromagnetic leads is studied theoretically. A noncollinear system is considered, where the QD is magnetized at an arbitrary angle with respect to the leads’ magnetization. The tunneling current is calculated in the coherent regime via the Keldysh nonequilibrium Green’s function (NEGF) formalism, incorporating the electron–electron interaction in the QD. We provide the first analytical solution for the Green’s function of the noncollinear DMS quantum dot system, solved via the equation of motion method under Hartree–Fock approximation. The transport characteristics (charge and spin currents, and tunnel magnetoresistance (TMR)) are evaluated for different voltage regimes. The interplay between spin-dependent tunneling and single-charge effects results in three distinct voltage regimes in the spin and charge current characteristics. The voltage range in which the QD is singly occupied corresponds to the maximum spin current and greatest sensitivity of the spin current to the QD magnetization orientation. The QD device also shows transport features suitable for sensor applications, i.e., a large charge current coupled with a high TMR ratio. - Highlights: ► The spin polarized transport through a diluted magnetic quantum dot is studied. ► The model is based on the Green’s function and the equation of motion method. The charge and spin currents and tunnel magnetoresistance (TMR) are investigated. ► The system is suitable for current-induced spin-transfer torque application. ► A large tunneling current and a high TMR are possible for sensor application.

  16. Quantum annealing

    OpenAIRE

    Ruiz, Alfonso de la Fuente

    2014-01-01

    Brief description on the state of the art of some local optimization methods: Quantum annealing Quantum annealing (also known as alloy, crystallization or tempering) is analogous to simulated annealing but in substitution of thermal activation by quantum tunneling. The class of algorithmic methods for quantum annealing (dubbed: 'QA'), sometimes referred by the italian school as Quantum Stochastic Optimization ('QSO'), is a promising metaheuristic tool for solving local search problems in mult...

  17. Response to parallel magnetic field of a dilute two-dimensional electron system across the metal-insulator transition

    International Nuclear Information System (INIS)

    The response to a parallel magnetic field of the very dilute insulating two-dimensional system of electrons in silicon metal-oxide-semiconductor field-effect transistors is dramatic and similar to that found on the conducting side of the metal-insulator transition: there is a large initial increase in resistivity with increasing field, followed by saturation to a value that is approximately constant above a characteristic magnetic field of about 1 T. This is unexpected behavior in an insulator that exhibits Efros-Shklovskii variable-range hopping in zero field, and appears to be a general feature of very dilute electron systems. copyright 1999 The American Physical Society

  18. User's manual for the ARMLID (Argonne metallic lithium/isotopic dilution) tritium assay system

    International Nuclear Information System (INIS)

    The Argonne Metallic Lithium - Isotopic Dilution (ARMLID) system described in this report, originally developed at ANL for other purposes, was recently redeployed to measure the tritium production rate (TPR) in a series of US/Japanese collaborative fusion blanket integral experiments, involving large assemblies of fusion breeder blanket materials that were irradiated with a fusion neutron source at FNS/JAERI, Japan. Whereas previous uses of the ARMUD scheme involved just a few samples, its application infusion blanket TPR mapping called for large sample numbers per experiment, implying a commensurate scale of sample fabrication and encapsulation, on one hand, and tritium extraction and counting on the other hand. To shorten the time required for these various tasks, yet still yield reliable and accurate results, both the sample fabrication - encapsulation facility and the tritium extraction system had to be extensively revised from original versions that were designed for accuracy, but not necessarily for speed. The present report describes overall revisions in sufficient detail to serve as a User's Manual for this facility, and/or suggest how a new system might be put together. Either possibility may develop in the near future, in support of ITER design studies. Preliminary and partial descriptions of various aspects and features of the system were presented orally, in the course of annual ANL/JAERI/UCLA ''workshops'', over the last 34 years, as well as elsewhere

  19. Effects of annealing on electrical and optical properties of a multilayer InAs/GaAs quantum dots system

    Directory of Open Access Journals (Sweden)

    Adenilson José Chiquito

    2004-09-01

    Full Text Available A systematic investigation of the properties of the InAs/GaAs self-assembled quantum dots (SAQDs system subjected to a post-growth annealing using capacitance-voltage, Raman scattering and photoluminescence measurements is presented. The application of both electrical and optical methods allowed us to obtain reliable information on the microscopic structural evolution of this system. The single layer and the multilayer quantum dots were found to respond differently to the annealing process, due to the differences in strain that occur in both systems. The diffusion activated by strain provoked the appearance of an InGaAs alloy layer in substitution to the quantum dots layers; this change occurred at the annealing temperature T = 600 ºC in the multilayer system. A single dot layer, however, was observed even after the annealing at T = 700 ºC. Moreover, the low temperature annealing was found to improve the homogeneity of the multilayer system and to decrease the electrical interlayer coupling.

  20. Dilution-of-Precision-Based Lunar Surface Navigation System Analysis Utilizing Earth-Based Assets

    Science.gov (United States)

    Welch, Bryan W.; Connolly, Joseph W.; Sands, Obed S.

    2007-01-01

    The NASA Vision for Space Exploration is focused on the return of astronauts to the Moon. Although navigation systems have already been proven in the Apollo missions to the Moon, the current exploration campaign will involve more extensive and extended missions requiring new concepts for lunar navigation. In contrast to Apollo missions, which were limited to the near-side equatorial region of the Moon, those under the Exploration Systems Initiative will require navigation on the Moon's limb and far side. These regions are known to have poor Earth visibility, but unknown is the extent to which a navigation system comprised solely of Earth-based tracking stations will provide adequate navigation solutions in these areas. This report presents a dilution-of-precision (DoP)-based analysis of the performance of a network of Earth-based assets. This analysis extends a previous analysis of a lunar network (LN) of navigation satellites by providing an assessment of the capability associated with a variety of assumptions. These assumptions pertain to the minimum provider elevation angle, nadir and zenith beam widths, and a total single failure in one of the Earth-based assets. The assessment is accomplished by making appropriately formed estimates of DoP. Different adaptations of DoP, such as geometrical DoP and positional DoP (GDoP and PDoP), are associated with a different set of assumptions regarding augmentations to the navigation receiver or transceiver.

  1. Electrode patterning and annealing processes of aluminum-doped zinc oxide thin films using a UV laser system

    Science.gov (United States)

    Hsiao, Wen-Tse; Tseng, Shih-Feng; Huang, Kuo-Cheng; Chiang, Donyau

    2013-01-01

    This study presents the hybrid processing (patterning and annealing) of aluminum-doped zinc oxide (AZO) films in a one-step process using a diode-pumped-solid-state (DPSS) ultraviolet (UV) laser system. The focused laser beam had a diameter of 30 μm and the positive defocused laser beam had a diameter of 1 mm. Both beams were adjusted using a UV laser-processing system. AZO films were deposited on Corning Eagle 2000® optical glass sheets with a thickness of 0.7 mm using a sputtering method. The deposited films were approximately 200 nm. The optoelectronic properties of machined (patterning and annealing) AZO films depend on the laser pulse frequency and galvanometer scanning speed. The surface morphology, roughness, optical transmittance, and resistivity of the films after the laser patterning and annealing processes were measured using a three-dimensional confocal laser scanning microscope, a field emission scanning electron microscope (FE-SEM), a spectrophotometer, and a four-point probe instrument, respectively. Experimental results indicate that the ablation depth increased as the pulse repetition frequency increased. The ablation depth also decreased as the galvanometric scanning speed increased. The transmittance spectra of the film changes slightly after laser annealing, and the average transmittance in the visible region is approximately 83%. All resistivity values of laser-patterned and annealed AZO films decreased significantly. The structural properties grain size was calculated firm the X-ray diffraction (XRD) spectra using the Scherrer equation that increased from 7.4 nm to 12 nm as the annealing scanning speed decreased from 800 mm/s to 400 mm/s. The root mean square (RMS) values of annealed AZO films treated with a laser scanning speed of 500 mm/s with a pulse repetition frequency of 40 kHz, 55 kHz, and 70 kHz were 1.1 nm, 1.2 nm, and 1.8 nm, respectively.

  2. Electroneutrality and ionic interactions in the modeling of mass transport in dilute electrochemical systems

    International Nuclear Information System (INIS)

    Highlights: → A simple ionic transport model including Coulombic interactions is proposed. → A connection between electroneutrality and Onsager's cross-flux terms is established. → Interionic flux densities are obtained from a constrained variational statement. → The numerical stiffness of the classical P-N-P system is bypassed using our proposed approach. - Abstract: We propose a simple, but novel mathematical and numerical approach to describe mass transport in dilute solutions, taking into consideration ionic interactions. Our proposed approach treats fluxes due to ionic interactions as additional unknowns in the transport equation. Through variational arguments, we derive a simple expression for these ionic fluxes in terms of the electroneutrality condition, which allows for a straightforward treatment of the new unknowns. Furthermore, a finite element formulation based on our mathematical model is presented. Finally, using the distribution of the interionic flux density and an energy dissipation function, we show that besides properly capturing flow due to ionic interactions, our model can also describe independent ionic flow as predicted by the conventional Nernst-Planck equation in regions where ionic interactions are weak.

  3. An interactive system for creating object models from range data based on simulated annealing

    International Nuclear Information System (INIS)

    In hazardous applications such as remediation of buried waste and dismantlement of radioactive facilities, robots are an attractive solution. Sensing to recognize and locate objects is a critical need for robotic operations in unstructured environments. An accurate 3-D model of objects in the scene is necessary for efficient high level control of robots. Drawing upon concepts from supervisory control, the authors have developed an interactive system for creating object models from range data, based on simulated annealing. Site modeling is a task that is typically performed using purely manual or autonomous techniques, each of which has inherent strengths and weaknesses. However, an interactive modeling system combines the advantages of both manual and autonomous methods, to create a system that has high operator productivity as well as high flexibility and robustness. The system is unique in that it can work with very sparse range data, tolerate occlusions, and tolerate cluttered scenes. The authors have performed an informal evaluation with four operators on 16 different scenes, and have shown that the interactive system is superior to either manual or automatic methods in terms of task time and accuracy

  4. An interactive system for creating object models from range data based on simulated annealing

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, W.A.; Hood, F.W.; King, R.H. [Colorado School of Mines, Golden, CO (United States). Center for Robotics and Intelligent Systems

    1997-05-01

    In hazardous applications such as remediation of buried waste and dismantlement of radioactive facilities, robots are an attractive solution. Sensing to recognize and locate objects is a critical need for robotic operations in unstructured environments. An accurate 3-D model of objects in the scene is necessary for efficient high level control of robots. Drawing upon concepts from supervisory control, the authors have developed an interactive system for creating object models from range data, based on simulated annealing. Site modeling is a task that is typically performed using purely manual or autonomous techniques, each of which has inherent strengths and weaknesses. However, an interactive modeling system combines the advantages of both manual and autonomous methods, to create a system that has high operator productivity as well as high flexibility and robustness. The system is unique in that it can work with very sparse range data, tolerate occlusions, and tolerate cluttered scenes. The authors have performed an informal evaluation with four operators on 16 different scenes, and have shown that the interactive system is superior to either manual or automatic methods in terms of task time and accuracy.

  5. OPTIMIZATION OF ELECTRICAL SUBMERSIBLE PUMP ARTIFICIAL LIFT SYSTEM FOR EXTRAHEAVY OILS THROUGH AN ANALYSIS OF BOTTOM DILUTION SCHEME

    OpenAIRE

    Carlos-Andrés Díaz-Prada; Flaminio Guarín-Arenas; Javier-Enrique González-Barbosa; César-Augusto García-Chinchilla; Esperanza de Jesús Cotes-León; Carolina Rodríguez-Walteros

    2010-01-01

    This study presents the analysis of the variables that have the greatest impact on energy requirements for an artificial lift system applied to extra heavy crude oils, considering an uncertainty behavior analysis through their sensitivity in the vertical flow modeling implemented for a Chichimene Field well. The selected variables are the viscosity and fluid density, the required artificial lift system pressure differential, well depth, the flow rate of produced fluids and the dilution percen...

  6. IMPULSE PHOTON ANNEALING EFFECT ON STRUCTURE AND PHASE COMPOSITION OF THIN FILM SYSTEMS ON BASIS OF SILICON AND TRANSITION METALS

    Directory of Open Access Journals (Sweden)

    M. Markevich

    2012-01-01

    Full Text Available The present paper investigates element composition,  regularities of structural and phase transformations in Si–Fe–Si and TiN–Ti–Si thin film systems in the process of impulse photon annealing depending on radiation energy density while applying such methods as transmission  electron microscopy, electron  diffraction analysis and energy dispersive x-ray microanalysis. Optimum characteristics of impulse photon annealing for formation FeSi2 thin films of β-modification on silicon and TiSi2 films in C54 modification have been determined in the paper.

  7. Insertable system for fast turnaround time microwave experiments in a dilution refrigerator

    OpenAIRE

    Ong, Florian R.; Orgiazzi, Jean-Luc; de Waard, Arlette; Frossati, Giorgio; Lupascu, Adrian

    2012-01-01

    Microwave experiments in dilution refrigerators are a central tool in the field of superconducting quantum circuits and other research areas. This type of experiments relied so far on attaching a device to the mixing chamber of a dilution refrigerator. The minimum turnaround time in this case is a few days as required by cooling down and warming up the entire refrigerator. We developed a new approach, in which a suitable sample holder is attached to a cold-insertable probe and brought in cont...

  8. X-ray absorption spectroscopy of diluted system by undulator photon source and multi-element solid-state detector

    CERN Document Server

    Tanida, H

    2001-01-01

    In order to measure the extended X-ray absorption fine structure (EXAFS) spectrum of an ultra-diluted system, an optics and detector control system for a synchrotron radiation beamline is developed. The undulator gap width is continuously tuned to obtain the maximum X-ray photon flux during the energy scan for the EXAFS measurement. A piezoelectric translator optimizes the parallelism of the double crystal in a monochromator at each measurement point to compensate for mechanical errors of the monochromator, resulting in a smooth and intense X-ray photon flux during the measurement. For a detection of a weak fluorescence signal from diluted samples, a 19-element solid-state detector and digital signal processor are used. A K-edge EXAFS spectrum of iron in a myoglobin aqueous solution with a concentration of 5.58 parts per million was obtained by this system.

  9. Electron spectroscopy of dilute nitrides

    International Nuclear Information System (INIS)

    The application of electron spectroscopies in dilute nitride semiconductor research for both chemical analysis and the determination of electronic and lattice vibrational properties is described. X-ray photoelectron spectroscopy of the nitrogen bonding configurations in dilute InNxSb1-x and InNxAs1-x alloys is presented. High resolution electron-energy-loss spectroscopy (HREELS) of the plasmon excitations in InNxSb1-x is shown to provide information on the electronic properties of the material, before and after annealing. HREELS is also used to investigate the GaN-like phonon modes in GaNxAs1-x alloys

  10. Redox, solubility and sorption chemistry of technetium in dilute to concentrated saline systems (KIT Scientific Report ; 7703)

    OpenAIRE

    Yalcintas, Ezgi

    2015-01-01

    This PhD work represents a comprehensive investigation of redox processes, solubility and sorption behaviour of technetium in the absence of complexing ligands extending from dilute to concentrated NaCl, MgCl2 and CaCl2 systems. The complete chemical, thermodynamic and activity models derived in this work provide key input for understanding the chemical behaviour of Tc in conditions relevant for nuclear waste disposal.

  11. Control parameter optimal tuning method based on annealing-genetic algorithm for complex electromechanical system

    Institute of Scientific and Technical Information of China (English)

    贺建军; 喻寿益; 钟掘

    2003-01-01

    A new searching algorithm named the annealing-genetic algorithm(AGA) was proposed by skillfully merging GA with SAA. It draws on merits of both GA and SAA ,and offsets their shortcomings. The difference from GA is that AGA takes objective function as adaptability function directly, so it cuts down some unnecessary time expense because of float-point calculation of function conversion. The difference from SAA is that AGA need not execute a very long Markov chain iteration at each point of temperature, so it speeds up the convergence of solution and makes no assumption on the search space,so it is simple and easy to be implemented. It can be applied to a wide class of problems. The optimizing principle and the implementing steps of AGA were expounded. The example of the parameter optimization of a typical complex electromechanical system named temper mill shows that AGA is effective and superior to the conventional GA and SAA. The control system of temper mill optimized by AGA has the optimal performance in the adjustable ranges of its parameters.

  12. Crystallization on a sphere using the simulated annealing algorithm implemented on H.P.C. systems

    OpenAIRE

    de Voogd, J. M.; Sloot, P. M. A.; Verbraeck, A.; Kerckhoffs, E.J.H.

    1993-01-01

    The research presented here is a comparison of the scalability of the simulated annealing algorithm on a vector super computer (CRAY Y-MP) with the scalability of a parallel implementation on a massively parallel transputer surface (Parsytec GCel with 512 nodes of typeT805). Some results of the annealing procedure applied to thecrystallization of Lennard-Jones particles on a sphere arepresented.

  13. Development of GM cryocooler separate type liquid-helium-free {sup 3}He-{sup 4}He dilution refrigerator system

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, Y; Ito, T; Umeno, T; Suzuki, Y; Yoshida, S; Kamioka, Y [Taiyo Nippon Sanso Corporation, 10 Okubo, Tsukuba-shi, 300-2611 (Japan); Maehata, K [Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, Fukuoka-shi, 819-0395 (Japan)], E-mail: Yoshihiro.Yamanaka@tn-sanso.co.jp

    2009-02-01

    We developed the new liquid-helium-free dilution refrigerator system, in which the Gifford-McMahon (GM) cycle cryocooler and dilution refrigerator (DR) unit are separated. We obtained the base temperature below 50 mK in this DR system. In usual liquid-helium-free DR systems, the DR unit directly couples with GM-cryocooler in the same vacuum chamber. Therefore the mechanical vibration of GM-cryocooler is hardly removed from DR unit. In order to eliminate the vibration problem, the separated vacuum chamber contacting the GM-cryocooler is connected with the DR unit chamber by the flexible hose with length of about 1 meter. Thin flexible tubes used for circulation of the refrigerant gas and radiation shield are installed in the connection hose. The {sup 4}He gas, cooled in the GM-cryocooler unit, transfers to the DR unit throw the thin flexible tubes. After cooling the DR unit, the gas returns to GM-cryocooler unit with cooling of the radiation shield. We expect that our separate-type dilution refrigerator becomes a useful piece of apparatus for the low temperature experiments.

  14. La1-xCexB6 (x≤0.1): spin-polaron regime in dilute magnetic system

    International Nuclear Information System (INIS)

    Precision measurements of charge transport characteristics (resistivity, magnetoresistance, Hall and Seebeck coefficients) and magnetic susceptibility have been carried out on high-quality single-crystals of the so-called dilute Kondo system La1-xCexB6 (χ≤0.1) in a wide temperature range 1.8-300 K. It is shown that the low temperature magnetic contribution in resistivity obeys the power law Δρ∼T-α, which corresponds to the regime of weak localization of charge carriers with the critical exponent values α=0.47-0.49 for cerium concentrations χ≤ 0.1. Simultaneously an asymptotic behavior of Seebeck coefficient S∼ -lnT is found together with nearly constant and negative Hall coefficient RH(T) in these dilute magnetic systems. The results of comprehensive analysis contradict to the predictions of Kondo-impurity approach for this archetypal strongly correlated electron system in dilute impurity limit. An alternative interpretation of the properties of La1-xCexB6 is developed and based on spin-polaron approach, Pauli paramagnetism and the density of states renormalization effects at low temperatures.

  15. High dilutions of Sulphur and relationship with the onion thrips, downy mildew incidence and yield of onion in organic system

    Directory of Open Access Journals (Sweden)

    Paulo Antonio de Souza Gonçalves

    2015-12-01

    Full Text Available The objective of this research was to evaluate high dilutions of Sulphur on the incidence of onion thrips, downy mildew, chlorophyll content and yield of onion under organic production system. The study was carried out at Ituporanga Experiment Station of Epagri, Santa Catarina State, Brazil, from August to December of 2011, 2012 and 2013. Treatments were foliar sprays of 0.5% Sulphur at high dilutions 6, 12 and 30 CH (CH, hahnemannian centesimal scale and untreated plot as control check. The experimental design was a randomized block design with four replications. The incidence and damage of onion thrips, reduction of the severity of downy mildew, chlorophyll index, total and commercial yield, bulb weight, postharvest conservation were not influenced by the treatments.

  16. Assessment of a fuzzy based flood forecasting system optimized by simulated annealing

    Science.gov (United States)

    Reyhani Masouleh, Aida; Pakosch, Sabine; Disse, Markus

    2010-05-01

    Flood forecasting is an important tool to mitigate harmful effects of floods. Among the many different approaches for forecasting, Fuzzy Logic (FL) is one that has been increasingly applied over the last decade. This method is principally based on the linguistic description of Rule Systems (RS). A RS is a specific combination of membership functions of input and output variables. Setting up the RS can be implemented either automatically or manually, the choice of which can strongly influence the resulting rule systems. It is therefore the objective of this study to assess the influence that the parameters of an automated rule generation based on Simulated Annealing (SA) have on the resulting RS. The study area is the upper Main River area, located in the northern part of Bavaria, Germany. The data of Mainleus gauge with area of 1165 km2 was investigated in the whole period of 1984 and 2004. The highest observed discharge of 357 m3/s was recorded in 1995. The input arguments of the FL model were daily precipitation, forecasted precipitation, antecedent precipitation index, temperature and melting rate. The FL model of this study has one output variable, daily discharge and was independently set up for three different forecast lead times, namely one-, two- and three-days ahead. In total, each RS comprised 55 rules and all input and output variables were represented by five sets of trapezoidal and triangular fuzzy numbers. Simulated Annealing, which is a converging optimum solution algorithm, was applied for optimizing the RSs in this study. In order to assess the influence of its parameters (number of iterations, temperature decrease rate, initial value for generating random numbers, initial temperature and two other parameters), they were individually varied while keeping the others fixed. With each of the resulting parameter sets, a full-automatic SA was applied to gain optimized fuzzy rule systems for flood forecasting. Evaluation of the performance of the

  17. An archived multi-objective simulated annealing for a dynamic cellular manufacturing system

    Science.gov (United States)

    Shirazi, Hossein; Kia, Reza; Javadian, Nikbakhsh; Tavakkoli-Moghaddam, Reza

    2014-05-01

    To design a group layout of a cellular manufacturing system (CMS) in a dynamic environment, a multi-objective mixed-integer non-linear programming model is developed. The model integrates cell formation, group layout and production planning (PP) as three interrelated decisions involved in the design of a CMS. This paper provides an extensive coverage of important manufacturing features used in the design of CMSs and enhances the flexibility of an existing model in handling the fluctuations of part demands more economically by adding machine depot and PP decisions. Two conflicting objectives to be minimized are the total costs and the imbalance of workload among cells. As the considered objectives in this model are in conflict with each other, an archived multi-objective simulated annealing (AMOSA) algorithm is designed to find Pareto-optimal solutions. Matrix-based solution representation, a heuristic procedure generating an initial and feasible solution and efficient mutation operators are the advantages of the designed AMOSA. To demonstrate the efficiency of the proposed algorithm, the performance of AMOSA is compared with an exact algorithm (i.e., ∈-constraint method) solved by the GAMS software and a well-known evolutionary algorithm, namely NSGA-II for some randomly generated problems based on some comparison metrics. The obtained results show that the designed AMOSA can obtain satisfactory solutions for the multi-objective model.

  18. Extraction Behaviour of Hexavalent Plutonium in the System of Dilute TBP/Kerosene

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    On the basis of the preparation and stabilization of Pu(Ⅵ), the distribution of it between dilute TBP/kerosene and aqueous phase is studied. The influences of the concentration of TBP, HNO3, A1(NO3)3, TBP and UO2(NO3)2 on the extraction of Pu(Ⅵ) by 5%TBP/kerosene are investigated at 28 ℃. The extraction reaction equation, the corresponding apparent equilibrium constant and the free energy change of it at temperature of 28 ℃ are obtained as follows:

  19. Additional ferromagnetic phases in the Fe-Nd-B system and the effect of a 600 deg C annealing

    International Nuclear Information System (INIS)

    In the Fe-Nd system an additional ferromagnetic phase with Tc 245± 10 deg C is found. In the ternary Fe-Nd-B system, magnetic analysis shows two ferromagnetic phases with Tc= 245 and 285 deg C in as-cast alloys, in addition to Fe14 Nd2 B. Those phases are formed through the eutectic solidification of a neodymium-rich liquid at the boron-poor side of the system, suppressing the formation of Fe14 Nd2 B. An annealing at 600 deg C dissolves the phase with Tc=245 deg C and develops Fe14 Nd2 B. This results in an Hei increase from 3.9 k O e in the as-cast to 14.1 k O e in the annealed condition for an Fe-80 at % Nd-5 at%B alloy. This suggests that the dissolution of additional ferromagnetic phases in the intergranular regions of sintered Fe-Nd-B magnets might be the positive effect of the 600 deg C annealing. (author)

  20. Crystallization on a sphere using the simulated annealing algorithm implemented on H.P.C. systems

    NARCIS (Netherlands)

    J.M. Voogd; P.M.A. Sloot

    1993-01-01

    The research presented here is a comparison of the scalability of the simulated annealing algorithm on a vector super computer (CRAY Y-MP) with the scalability of a parallel implementation on a massively parallel transputer surface (Parsytec GCel with 512 nodes of typeT805). Some results of the anne

  1. Survey of the chemical diffusion at infinite dilution in the nickel-plutonium and aluminium-uranium systems

    International Nuclear Information System (INIS)

    Solubility S0 and chemical diffusion coefficients DPuNi at infinite dilution of plutonium in nickel have been determined by autoradiography α in poly-phased system by the welded couples method: S0 varies from 40 to 80.10-6 (atomic concentration) and DPuNi follows an Arrhenius law D = D0 exp (-Q/RT) with 0.03 cm2/s 0 2/s and 46000 cal/mole 2/s and the activation energy lies between 24000 and 34000 cal/mole. (author)

  2. Sharply increasing effective mass: a precursor of a spontaneous spin polarization in a dilute two-dimensional electron system

    International Nuclear Information System (INIS)

    We have measured the effective mass, m, and Lande g factor in very dilute two-dimensional electron systems in silicon. Two independent methods have been used: (i) measurements of the magnetic field required to fully polarize the electrons' spins and (ii) analysis of the Shubnikov-de Haas oscillations. We have observed a sharp increase of the effective mass with decreasing electron density while the g factor remains nearly constant and close to its value in bulk silicon. The corresponding strong rise of the spin susceptibility χ ∝ gm may be a precursor of a spontaneous spin polarization; unlike in the Stoner scenario, it originates from the enhancement of the effective mass rather than from the increase of g factor. Furthermore, using tilted magnetic fields, we have found that the enhanced effective mass is independent of the degree of spin polarization and, therefore, its increase is not related to spin exchange effects, in contradiction with existing theories. Our results show that the dilute 2D electron system in silicon behaves well beyond a weakly interacting Fermi liquid

  3. Optical Design of Dilute Nitride Quantum Wells Vertical Cavity Semiconductor Optical Amplifiers for Communication Systems

    Directory of Open Access Journals (Sweden)

    Faten A. Chaqmaqchee

    2016-04-01

    Full Text Available III-V semiconductors components such as Gallium Arsenic (GaAs, Indium Antimony (InSb, Aluminum Arsenic (AlAs and Indium Arsenic (InAs have high carrier mobilities and direct energy gaps. This is making them indispensable for today’s optoelectronic devices such as semiconductor lasers and optical amplifiers at 1.3 μm wavelength operation. In fact, these elements are led to the invention of the Gallium Indium Nitride Arsenic (GaInNAs, where the lattice is matched to GaAs for such applications. This article is aimed to design dilute nitride GaInNAs quantum wells (QWs enclosed between top and bottom of Aluminum (Gallium Arsenic Al(GaAs distributed bragg mirrors (DBRs using MATLAB® program. Vertical cavity semiconductor optical amplifiers (VCSOAs structures are based on Fabry Perot (FP method to design optical gain and bandwidth gain to be operated in reflection and transmission modes. The optical model gives access to the contact layer of epitaxial structure and the reflectivity for successive radiative modes, their lasing thresholds, emission wavelengths and optical field distributions in the laser cavity.

  4. 40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.

    Science.gov (United States)

    2010-07-01

    ...-displacement pump (PDP), a subsonic venturi (SSV), or an ultrasonic flow meter (UFM). Combined with an upstream... dilution system, you may use a laminar flow element, an ultrasonic flow meter, a subsonic venturi, a... § 1065.240 Dilution air and diluted exhaust flow meters. (a) Application. Use a diluted exhaust...

  5. 40 CFR 90.421 - Dilute gaseous exhaust sampling and analytical system description.

    Science.gov (United States)

    2010-07-01

    ...) Conform to the continuous NOX, CO, or CO2 sampling and analysis system to the specifications of 40 CFR... analytical system description. 90.421 Section 90.421 Protection of Environment ENVIRONMENTAL PROTECTION... analytical system description. (a) General. The exhaust gas sampling system described in this section...

  6. A quantum annealing approach for fault detection and diagnosis of graph-based systems

    Science.gov (United States)

    Perdomo-Ortiz, A.; Fluegemann, J.; Narasimhan, S.; Biswas, R.; Smelyanskiy, V. N.

    2015-02-01

    Diagnosing the minimal set of faults capable of explaining a set of given observations, e.g., from sensor readouts, is a hard combinatorial optimization problem usually tackled with artificial intelligence techniques. We present the mapping of this combinatorial problem to quadratic unconstrained binary optimization (QUBO), and the experimental results of instances embedded onto a quantum annealing device with 509 quantum bits. Besides being the first time a quantum approach has been proposed for problems in the advanced diagnostics community, to the best of our knowledge this work is also the first research utilizing the route Problem → QUBO → Direct embedding into quantum hardware, where we are able to implement and tackle problem instances with sizes that go beyond previously reported toy-model proof-of-principle quantum annealing implementations; this is a significant leap in the solution of problems via direct-embedding adiabatic quantum optimization. We discuss some of the programmability challenges in the current generation of the quantum device as well as a few possible ways to extend this work to more complex arbitrary network graphs.

  7. Design of a scanning gate microscope for mesoscopic electron systems in a cryogen-free dilution refrigerator.

    Science.gov (United States)

    Pelliccione, M; Sciambi, A; Bartel, J; Keller, A J; Goldhaber-Gordon, D

    2013-03-01

    We report on our design of a scanning gate microscope housed in a cryogen-free dilution refrigerator with a base temperature of 15 mK. The recent increase in efficiency of pulse tube cryocoolers has made cryogen-free systems popular in recent years. However, this new style of cryostat presents challenges for performing scanning probe measurements, mainly as a result of the vibrations introduced by the cryocooler. We demonstrate scanning with root-mean-square vibrations of 0.8 nm at 3 K and 2.1 nm at 15 mK in a 1 kHz bandwidth with our design. Using Coulomb blockade thermometry on a GaAs/AlGaAs gate-defined quantum dot, we demonstrate an electron temperature of 45 mK. PMID:23556823

  8. Faster annealing schedules for quantum annealing

    OpenAIRE

    Morita, Satoshi

    2007-01-01

    New annealing schedules for quantum annealing are proposed based on the adiabatic theorem. These schedules exhibit faster decrease of the excitation probability than a linear schedule. To derive this conclusion, the asymptotic form of the excitation probability for quantum annealing is explicitly obtained in the limit of long annealing time. Its first-order term, which is inversely proportional to the square of the annealing time, is shown to be determined only by the information at the initi...

  9. Modeling and Simulation of Water Allocation System Based on Simulated Annealing Hybrid Genetic Algorithm

    Science.gov (United States)

    Zhu, Jiulong; Wang, Shijun

    Presently water resource in most watersheds in China is distributed in terms of administrative instructions. This kind of allocation method has many disadvantages and hampers the instructional effect of market mechanism on water allocation. The paper studies South-to-North Water Transfer Project and discusses water allocation of the node lakes along the Project. Firstly, it advanced four assumptions. Secondly, it analyzed constraint conditions of water allocation in terms of present state of water allocation in China. Thirdly, it established a goal model of water allocation and set up a systematic model from the angle of comprehensive profits of water utilization and profits of the node lakes. Fourthly, it discussed calculation method of the model by means of Simulated Annealing Hybrid Genetic Algorithm (SHGA). Finally, it validated the rationality and validity of the model by a simulation testing.

  10. A study on eco-supplement of soybean and maize mixcropping system with 15N isotope dilution

    International Nuclear Information System (INIS)

    An eco-supplement research of maize and soybean standing plants in their mixcropping systems was conducted in plot and potting experiments using 15N isotope dilution method. The results shown that the %Ndfs and %Ndff of the maize plants in mixculture had a decrease by 9.13%∼24.58% and 7.15%∼22.52% respectively compared with the monoculture. The Ndft was 18.44%∼35.32%. The 8.75%∼24.05% of nitrogen of the maize plants in the mixculture were from the Ndfa of soybean plants. It is one of the reasons that the %Ndfa of soybean plants had an increase by 29.10%∼32.69% in the mixculture of maize and soybean plants. A mixcropping field demonstration was done. The output value per hectare had an increase by 43.12% compared with soybean monoculture and 33.44% compared with mainze monoculture. In the soybean and maize mixcropping system in which the ratio of standing plants is 2:1, the plant nitrogen content of two crops is higher and the consumption of soil nitrogen is lower than in the other mixecropping system. (5 tabs.)

  11. Isotopic dilution kinetics of phosphate and potassium ions in soil-solution system: its use in long term trials

    International Nuclear Information System (INIS)

    The method of isotopic dilution analysis is explained. The experimental procedure developped for PO4 and K ions in a stirred soil-solution system is described. The most important modifications used concern the separation of the soil solution from stirred soil-solution system with millipore filters (0,2 or 0,01 micron pore size). The following 3 kinetic parameters of isotopically exchangeable phosphate of soil are measured: r' /R, r' is the radioactivity remaining in the solution after one minute of isotopic exchange and R the total radioactivity injected in the system, n the slope of the straightline which, in logarithmic coordinates, gives the decrease of the radioactivity remaining in the solution versus time, and c the phosphate-ions concentration in the solution. Results obtained on soil samples taken up in 1938 and 1972 from a long term trial field situated a Grignon (France) are given. It can be measured that the decrease of the organic carbon between 1938 and 1972 in all treatments on all plots (farm-yard manure, N P K, N K, NP, P K and without fertilizer) increases the absorbing capacity of soil for phosphate and potassium ions. It is concluded that the actual techniques of cultivation, which cause a decrease in the organic matter level of soil, induce a decrease of the effect of phosphoric and potassium fertilizers

  12. 40 CFR 89.419 - Dilute gaseous exhaust sampling and analytical system description.

    Science.gov (United States)

    2010-07-01

    ... requires: (i) Bag sampling (see 40 CFR part 1065) and analytical capabilities (see 40 CFR part 1065), as... engines. This system utilizes the CVS concept (described in 40 CFR part 1065, subparts A and B) of...-CVS shall conform to all of the requirements listed for the exhaust gas PDP-CVS in 40 CFR part...

  13. 40 CFR 91.421 - Dilute gaseous exhaust sampling and analytical system description.

    Science.gov (United States)

    2010-07-01

    ...-alignment and dispersion specifications in 40 CFR pat 1065, subpart C. (C) Use only analytical gases conforming to the specifications of 40 CFR 1065.750 for calibration, zero, and span checks. (D) Use a... to the continuous NOX, CO, or CO2 sampling and analysis system to the specifications of 40 CFR...

  14. Non-Hermitian Quantum Annealing and Superradiance

    CERN Document Server

    Nesterov, Alexander I; de la Cruz, Fermín Aceves; Zepeda, Juan Carlos Beas

    2015-01-01

    We consider the non-Hermitian quantum annealing for the one-dimentional Ising spin chain, and for a large number of qubits. We show that the annealing time is significanly reduced for the non-Hermitian algorithm in comparison with the Hermitian one. We also demonstrtate the relation of the non-Hermitian quantum annealing with the superadiance transition in this system.

  15. Residual Energies after Slow Quantum Annealing

    OpenAIRE

    Suzuki, Sei; Okada, Masato

    2005-01-01

    Features of the residual energy after the quantum annealing are investigated. The quantum annealing method exploits quantum fluctuations to search the ground state of classical disordered Hamiltonian. If the quantum fluctuation is reduced sufficiently slowly and linearly by the time, the residual energy after the quantum annealing falls as the inverse square of the annealing time. We show this feature of the residual energy by numerical calculations for small-sized systems and derive it on th...

  16. Isothermal Vapor–Liquid Equilibria in Diluted Polystyrene + Butanone-2 System

    Czech Academy of Sciences Publication Activity Database

    Pavlíček, Jan; Bogdanić, Grozdana; Wichterle, Ivan

    Ozarow Mazowiecki : Nobell Compressing sp. z o.o, 2015 - (Kosinsky, K.; Urbanczyk, M.; Žerko, S.), s. 196 ISBN N. [European Symposium on Applied Thermodynamics ESAT 2015 /28./. Athens (GR), 11.06.2015-14.06.2015] R&D Projects: GA ČR GA15-19542S Institutional support: RVO:67985858 Keywords : polymer-solvent system * experimental data * vapour-liquid equilibria Subject RIV: CF - Physical ; Theoretical Chemistry

  17. Magnetic properties of dilute random magnetic anisotropy systems (DyxY1-x)Al2

    International Nuclear Information System (INIS)

    The magnetic phase diagram for the RMA system DyxY1-xAl2 is determined. For x ≤ 0.30 a PM/SG transition is found, while for x > 0.30 a CSG phase exists. No long range magnetic order appears, yet the initial susceptibility diverges at and below the PM/CSG transition. Scaling analysis indicates phase transitions, and the critical exponents have been determined

  18. Theory of Quantum Annealing of an Ising Spin Glass

    OpenAIRE

    Santoro, Giuseppe E.; Martonak, Roman; Tosatti, Erio; Car, Roberto

    2002-01-01

    Probing the lowest energy configuration of a complex system by quantum annealing was recently found to be more effective than its classical, thermal counterpart. Comparing classical and quantum Monte Carlo annealing protocols on the random two-dimensional Ising model we confirm the superiority of quantum annealing relative to classical annealing. We also propose a theory of quantum annealing, based on a cascade of Landau-Zener tunneling events. For both classical and quantum annealing, the re...

  19. Effect of annealing on the microstructures and Vickers hardness at room temperature of intermetallics in Mo-Si system

    Institute of Scientific and Technical Information of China (English)

    YANG Haibo; LI Wei; SHAN Aidang; WU Jiansheng

    2004-01-01

    The microstructures and Vickers hardness at room temperature of arc-melting processed intermetallics of Mo5Si3-MoSi2 hypoeutectic alloy and hypereutectic alloy annealed at 1200℃ for different time were investigated. Lamellar structure consisted of Mo5Si3 (D8m) phase and MoSi2 (C11b) phase was observed in all the alloys. For Mo5Si3-MoSi2 hypoeutectic alloy, the lamellar structure was found only after annealing and developed well with fine spacing on the order of hundred nanometers after annealing at 1200℃ for 48 h. But when the annealing time was up to 96 h, the well-developed lamellar structure was destroyed. For Mo5Si3-MoSi2 hypereutectic alloy, the lamellar structure was found both before and after annealing. However the volume fraction and spacing of the lamellar structure did not change significantly before and after annealing. The effects of the formation, development and destruction of lamellar structure on Vickers hardness of alloys were also investigated. When Mo5Si3-MoSi2 hypoeutectic alloy annealed at 1200℃ for 48 h, the Vickers hardness was improved about 19% compared with that without annealing and formation of lamellar structure. The highest Vickers hardness of Mo5Si3-MoSi2 hypereutectic was increasing about 18% when annealing at 1200℃ for 48 h.

  20. Effect of the dilution factor on 18FDG and Na18F samples for bacterial endotoxin test using PTS (portable test system)

    International Nuclear Information System (INIS)

    18FDG and Na18F are radiopharmaceuticals produced as sterile solutions suitable for intravenous administration, which must contain no more than 175 EV/V. The most commonly used approach to detect endotoxins is the gelclot technique that requires 60 minutes for results. For radiopharmaceuticals containing short-life radionuclides, such as 18F, there is an increasing interest for faster quality control methods. FDA licensed the Endosafe, PTS, a kinetic chromogenic endotoxin detection system that takes about 15 minutes for results. As other techniques, PTS test is susceptible to interferences which can be solved by product dilution. The aim of this study was to establish the best dilution of 18FDG and Na18F for PTS analysis. Two different dilution factors for 18FDG and 1:10 for Na18F were essayed: 1:10 and 1:100. 18FDG and Na18 solutions were prepared by the addition of LAL reagent water. Considering the assay acceptance criteria, the best dilution factor was 1:100 for 18FDG and 1:10 for Na18F. The recovery of the product positive control was 98-12% for 18FDG 1:100 and 104-120% for Na18F 1:10, which were, in both cases, within the specification (50-200%) and very close to 100%. Results obtained with these dilution studies were important to establish the most appropriate and non-interfering dilution factor for 18FDG and Na18F routine endotoxin test. (author)

  1. Effect of the dilution factor on {sup 18}FDG and Na{sup 18}F samples for bacterial endotoxin test using PTS (portable test system)

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Marina B.; Costa, Flavia M.; Ferreira, Soraya Z., E-mail: mbs@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Unidade de Pesquisa e Producao de Radiofarmacos

    2011-07-01

    {sup 18}FDG and Na{sup 18}F are radiopharmaceuticals produced as sterile solutions suitable for intravenous administration, which must contain no more than 175 EV/V. The most commonly used approach to detect endotoxins is the gelclot technique that requires 60 minutes for results. For radiopharmaceuticals containing short-life radionuclides, such as {sup 18}F, there is an increasing interest for faster quality control methods. FDA licensed the Endosafe, PTS, a kinetic chromogenic endotoxin detection system that takes about 15 minutes for results. As other techniques, PTS test is susceptible to interferences which can be solved by product dilution. The aim of this study was to establish the best dilution of {sup 18}FDG and Na{sup 18}F for PTS analysis. Two different dilution factors for {sup 18}FDG and 1:10 for Na{sup 18}F were essayed: 1:10 and 1:100. {sup 18}FDG and Na{sup 18} solutions were prepared by the addition of LAL reagent water. Considering the assay acceptance criteria, the best dilution factor was 1:100 for {sup 18}FDG and 1:10 for Na{sup 18}F. The recovery of the product positive control was 98-12% for {sup 18}FDG 1:100 and 104-120% for Na{sup 18}F 1:10, which were, in both cases, within the specification (50-200%) and very close to 100%. Results obtained with these dilution studies were important to establish the most appropriate and non-interfering dilution factor for {sup 18}FDG and Na{sup 18}F routine endotoxin test. (author)

  2. Extraction theory and form of the extraction complex of terbium, erbium, ytterbium, and lutecium in the synergistic system kerosene/HTTA/TBP/dilute HNO3

    International Nuclear Information System (INIS)

    Analysis of extensive distribution data taken in the synergistic system kerosene/HTTA/TBP/dilute HNO3 indicates that the rare earths terbium, erbium, ytterbium, and lutecium are extracted into the organic phase as M(NO3)(TTA)2(TBP)2. The thermodynamic stability constants for the four metals in the two-phase system have been calculated to be 41 +- 10, 26 +- 10, 19 +- 10, and 14 +- 10 percent, respectively

  3. Criticality experiments: analysis, evaluation, and programs. 8. Prompt Neutron Decay Constants in Uranium Diluted with Matrix Material Systems

    International Nuclear Information System (INIS)

    Rossi-Alpha measurements were performed on uranium diluted with matrix material systems to determine the prompt neutron decay constants. These constants represent an eigenvalue characteristic of these particular critical assemblies, which can be experimentally measured by the Rossi-Alpha or pulse neutron source techniques and calculated by a deterministic or Monte Carlo method. In the measurements presented in this paper, highly enriched foils diluted in various X/235U ratios with polyethylene and SiO2, and polyethylene and aluminum were assembled to a high multiplication, and the prompt neutron decay constants were obtained by the Rossi-Alpha technique. The uranium diluted with matrix material experiments were fueled with highly enriched uranium foils. The average dimensions of the bare foils were 22.86 cm squared and 0.00762 cm thick. The foils were laminated with plastic sheets to reduce the amount of airborne contamination. Each foil weighed ∼70 g. The diluent material consisted of SiO2, or 6061 aluminum plates, which were embedded into polyethylene plates. The SiO2 and aluminum plates were 22.86 cm square and 0.64 cm thick. The polyethylene plates were 39.12 cm square and 1.91 cm thick. Each polyethylene plate had a central recess whose dimensions were 22.86 cm by 22.86 cm by 0.64 cm deep and was used to accommodate the SiO2, or aluminum plates as well as the uranium foils. There were eight 39.12-cm-squared by 2.54-cm-thick high density polyethylene plates that form the top and bottom reflectors (four at the top and four at the bottom). Also, one of the polyethylene plates located in the center of the assembly had holes drilled in a radial direction to accommodate neutron detectors. Four 3He detectors were placed in this plate. The 3He detectors were 1.27 cm in diameter and ∼15 cm long. Rossi-Alpha measurements were performed at several subcritical separations for both experiments. The data were collected with a type I time analyzer (PATRM). This time

  4. Development and characterization of dilutable self-microemulsifying premicroemulsion systems (SMEPMS as templates for preparation of nanosized particulates

    Directory of Open Access Journals (Sweden)

    Lin SF

    2013-09-01

    Full Text Available Shen-Fu Lin,1 Ying-Chen Chen,2 Hsiu-O Ho,2 Wei-Yu Huang,2 Ming-Thau Sheu,2,3 Der-Zen Liu1,4 1Graduate Institute of Biomedical Materials and Tissue Engineering, College of Oral Medicine, 2School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan; 3Clinical Research Center and Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei, Taiwan; 4Center for General Education, Hsuan Chuang University, Hsinchu, Taiwan Abstract: The utilization of self-microemulsifying premicroemulsion systems (SMEPMS as templates for preparing poorly water-soluble compounds in the nanosized range represents a promising strategy. Fenofibrate was formulated with n-butyl L-lactate, Tween 80, and a number of cosurfactants (ethanol, 1-propanol, and PEG 600, diluted with the water phase (either water or saccharide solution and then subjected to a freeze-drying (FD process to obtain SMEPMS nanosized particulates. Results demonstrated that the particle size after resuspension of these FD SMEPMS nanosized particulates in water was too large, so the addition of saccharide solutions (lactose, mannitol, glucose, sucrose, and trehalose as the solid carrier to prevent particles from aggregating seemed to be necessary and workable due to steric hindrance and repulsion. However, instability of these resuspended FD nanosized particulates after 30–90 minutes still occurred, and the addition of 0.5% sodium lauryl sulfate in the resuspending medium was able to retard the aggregation and maintain the particle size within the nano-range. Evaluation by scanning electron microscopy and X-ray powder diffraction also confirmed the results. It was concluded that using an SMEPMS formulation with PEG 600 as the cosurfactant, and in the presence of a suitable saccharide as an anticaking agent and FD process were able to produce fenofibrate nanoparticles. Keywords: fenofibrate, saccharides, freeze-drying, nanoparticles

  5. Dilute oriented loop models

    Science.gov (United States)

    Vernier, Eric; Lykke Jacobsen, Jesper; Saleur, Hubert

    2016-02-01

    We study a model of dilute oriented loops on the square lattice, where each loop is compatible with a fixed, alternating orientation of the lattice edges. This implies that loop strands are not allowed to go straight at vertices, and results in an enhancement of the usual {{O}}(n) symmetry to {{U}}(n). The corresponding transfer matrix acts on a number of representations (standard modules) that grows exponentially with the system size. We derive their dimension and those of the centralizer by both combinatorial and algebraic techniques. A mapping onto a field theory permits us to identify the conformal field theory governing the critical range, n≤slant 1. We establish the phase diagram and the critical exponents of low-energy excitations. For generic n, there is a critical line in the universality class of the dilute {{O}}(2n) model, terminating in an {{SU}}(n+1) point. The case n = 1 maps onto the critical line of the six-vertex model, along which exponents vary continuously.

  6. Comparison of the Cathra Repliscan II, the AutoMicrobic system Gram-Negative General Susceptibility-Plus Card, and the Micro-Media System Fox Panel for dilution susceptibility testing of gram-negative bacilli.

    OpenAIRE

    Reiber, N E; Kelly, M T; Latimer, J M; Tison, D L; Hysmith, R M

    1985-01-01

    A comparative evaluation was done to test the accuracy of the Cathra Repliscan II agar dilution system (Diagnostic Equipment, Inc., St. Paul, Minn.), the AutoMicrobic system with Gram-Negative General Susceptibility-Plus Card (Vitek Systems, Inc., Hazelwood, Mo.), and the Micro-Media Fox Panel micro broth dilution system (Micro-Media Systems, Inc., San Jose, Calif.) in determining MICs of 12 antibiotics for 200 gram-negative bacilli. Of the 200 strains tested, 12 isolates did not grow in one ...

  7. Enhancement of the electrical characteristics of MOS capacitors by reducing the organic content of H2O-diluted Spin-On-Glass based oxides

    International Nuclear Information System (INIS)

    In this work, the physical, chemical and electrical properties of Metal-Oxide-Semiconductor (MOS) capacitors with Spin-On-Glass (SOG)-based thin films as gate dielectric have been investigated. Experiments of SOG diluted with two different solvents (2-propanol and deionized water) were done in order to reduce the viscosity of the SOG solution so that thinner films (down to ∼20 nm) could be obtained and their general characteristics compared. Thin films of SOG were deposited on silicon by the sol-gel technique and they were thermally annealed using conventional oxidation furnace and Rapid Thermal Processing (RTP) systems within N2 ambient after deposition. SOG dilution using non-organic solvents like deionized water and further annealing (at relatively high temperatures ≥450 deg. C) are important processes intended to reduce the organic content of the films. Fourier-Transform Infrared (FTIR) Spectroscopy results have shown that water-diluted SOG films have a significant reduction in their organic content after increasing annealing temperature and/or dilution percentage when compared to those of undiluted SOG films. Both current-voltage (I-V) and capacitance-voltage (C-V) measurements show better electrical characteristics for SOG-films diluted in deionized water compared to those diluted in 2-propanol (which is an organic solvent). The electrical characteristics of H2O-diluted SOG thin films are very similar to those obtained from high quality thermal oxides so that their application as gate dielectrics in MOS devices is promising. Finally, it has been demonstrated that by reducing the organic content of SOG-based thin films, it is possible to obtain MOS devices with better electrical properties.

  8. Enhancement of the electrical characteristics of MOS capacitors by reducing the organic content of H{sub 2}O-diluted Spin-On-Glass based oxides

    Energy Technology Data Exchange (ETDEWEB)

    Molina, Joel, E-mail: jmolina@inaoep.mx [National Institute of Astrophysics, Optics and Electronics, Electronics Department, Luis Enrique Erro 1, PO BOX 51 and 216, Tonantzintla, Puebla 72000 (Mexico); Munoz, Ana; Torres, Alfonso; Landa, Mauro; Alarcon, Pablo; Escobar, Manuel [National Institute of Astrophysics, Optics and Electronics, Electronics Department, Luis Enrique Erro 1, PO BOX 51 and 216, Tonantzintla, Puebla 72000 (Mexico)

    2011-10-25

    In this work, the physical, chemical and electrical properties of Metal-Oxide-Semiconductor (MOS) capacitors with Spin-On-Glass (SOG)-based thin films as gate dielectric have been investigated. Experiments of SOG diluted with two different solvents (2-propanol and deionized water) were done in order to reduce the viscosity of the SOG solution so that thinner films (down to {approx}20 nm) could be obtained and their general characteristics compared. Thin films of SOG were deposited on silicon by the sol-gel technique and they were thermally annealed using conventional oxidation furnace and Rapid Thermal Processing (RTP) systems within N{sub 2} ambient after deposition. SOG dilution using non-organic solvents like deionized water and further annealing (at relatively high temperatures {>=}450 deg. C) are important processes intended to reduce the organic content of the films. Fourier-Transform Infrared (FTIR) Spectroscopy results have shown that water-diluted SOG films have a significant reduction in their organic content after increasing annealing temperature and/or dilution percentage when compared to those of undiluted SOG films. Both current-voltage (I-V) and capacitance-voltage (C-V) measurements show better electrical characteristics for SOG-films diluted in deionized water compared to those diluted in 2-propanol (which is an organic solvent). The electrical characteristics of H{sub 2}O-diluted SOG thin films are very similar to those obtained from high quality thermal oxides so that their application as gate dielectrics in MOS devices is promising. Finally, it has been demonstrated that by reducing the organic content of SOG-based thin films, it is possible to obtain MOS devices with better electrical properties.

  9. Austenite formation during intercritical annealing

    Directory of Open Access Journals (Sweden)

    A. Lis

    2008-07-01

    Full Text Available Purpose: of this paper is the effect of the soft annealing of initial microstructure of the 6Mn16 steel on the kinetics of the austenite formation during next intercritical annealing.Design/methodology/approach: Analytical TEM point analysis with EDAX system attached to Philips CM20 was used to evaluate the concentration of Mn, Ni and Cr in the microstructure constituents of the multiphase steel and mainly Bainite- Martensite islands.Findings: The increase in soft annealing time from 1-60 hours at 625°C increases Mn partitioning between ferrite and cementite and new formed austenite and decreases the rate of the austenite formation during next intercritical annealing in the (α+γ temperature range at 700 and 750°C. The general equations for carbide dissolution and austenite formation in intercritical temperature range were established.Research limitations/implications: The final multiphase microstructure can be optimised by changing the time / temperature parameters of the intercritical heating in the (α+γ temperature range.Originality/value: The knowledge of partitioning of alloying elements mainly Mn during soft annealing and intercritical heating is very important to optimise the processing technology of intercritical annealing for a given amount of the austenite.

  10. Mercury species transformations in marine and biological systems studied by isotope dilution mass spectrometry and stable isotope tracers

    OpenAIRE

    Lambertsson, Lars

    2005-01-01

    This thesis focuses on the implementation of species-specific isotope dilution (SSID) methodology and stable isotope tracers to determine mercury species occurrence and transformation processes in-situ and during sample treatment. Isotope enriched tracers of methyl-, ethyl- and inorganic mercury were synthesised and applied in different combinations to marine and biological samples. Experimental results were obtained using gas chromatography-inductively coupled plasma-mass spectrometry (GC-IC...

  11. Use of an “electronic tongue” in the assessment of highly diluted systems

    Directory of Open Access Journals (Sweden)

    Antônio Riul Jr

    2011-09-01

    Full Text Available Introduction: “Eletronic tongue” is a device commonly used in the analysis of tastants, heavy metal ions, fruit juice, wines and also in the development of biosensors [1-3]. Briefly, the e-tongue is constituted by sensing units formed by ultrathin films of distinct materials deposited on gold interdigitated electrodes, which are immersed in liquid samples, followed by impedance spectroscopy measurements [1]. The e-tongue sensor is based on the global selectivity concept, i.e., the materials forming the sensing units are not selective to any substance in the samples, therefore, it allows the grouping of information into distinct patterns of response, enabling the distinction of complex liquid systems [1]. Aim: Our aim was to use e-tongue system for the assessment the homeopathic medicine Belladonna at different degrees of dilution, in attempt to differentiate highly diluted systems. Methods: Ultrathin films forming the sensing units were prepared by the layer-by-layer technique [4], using conventional polyelectrolytes such as poly(sodium styene sulfonate (PSS and poly(allylamine hydrochloride (PAH, chitosan and poly(3,4-ethylenedioxythiophene (PEDOT. Homeopathic medicines (Belladonna 1cH, 6cH, 12cH and 30cH were prepared by dilution and agitation according to Hahnemann´s method [5], using ethanol at 30% (w/w as vehicle. Experimental data acquisition was conducted by blind tests measurements involving Belladonna samples and the vehicle used in the dilutions. Five independent and consecutive measurements were taken for each solution at 1 kHz, which were further analysed by Principal Component Analysis (PCA, a statistical method largely employed to reduce the dimensionality of the original data without losing information in the correlation of the samples [3]. Results: Figure 1 shows that the five independent measurements are grouped quite closed each other for each solution analysed, with a clear

  12. Quantum Annealing for Clustering

    OpenAIRE

    Kurihara, Kenichi; Tanaka, Shu; Miyashita, Seiji

    2014-01-01

    This paper studies quantum annealing (QA) for clustering, which can be seen as an extension of simulated annealing (SA). We derive a QA algorithm for clustering and propose an annealing schedule, which is crucial in practice. Experiments show the proposed QA algorithm finds better clustering assignments than SA. Furthermore, QA is as easy as SA to implement.

  13. Classical Simulated Annealing Using Quantum Analogues

    Science.gov (United States)

    La Cour, Brian R.; Troupe, James E.; Mark, Hans M.

    2016-06-01

    In this paper we consider the use of certain classical analogues to quantum tunneling behavior to improve the performance of simulated annealing on a discrete spin system of the general Ising form. Specifically, we consider the use of multiple simultaneous spin flips at each annealing step as an analogue to quantum spin coherence as well as modifications of the Boltzmann acceptance probability to mimic quantum tunneling. We find that the use of multiple spin flips can indeed be advantageous under certain annealing schedules, but only for long anneal times.

  14. Classical Simulated Annealing Using Quantum Analogues

    Science.gov (United States)

    La Cour, Brian R.; Troupe, James E.; Mark, Hans M.

    2016-08-01

    In this paper we consider the use of certain classical analogues to quantum tunneling behavior to improve the performance of simulated annealing on a discrete spin system of the general Ising form. Specifically, we consider the use of multiple simultaneous spin flips at each annealing step as an analogue to quantum spin coherence as well as modifications of the Boltzmann acceptance probability to mimic quantum tunneling. We find that the use of multiple spin flips can indeed be advantageous under certain annealing schedules, but only for long anneal times.

  15. A Novel Low-Power, High-Performance, Zero-Maintenance Closed-Path Trace Gas Eddy Covariance System with No Water Vapor Dilution or Spectroscopic Corrections

    Science.gov (United States)

    Sargent, S.; Somers, J. M.

    2015-12-01

    Trace-gas eddy covariance flux measurement can be made with open-path or closed-path analyzers. Traditional closed-path trace-gas analyzers use multipass absorption cells that behave as mixing volumes, requiring high sample flow rates to achieve useful frequency response. The high sample flow rate and the need to keep the multipass cell extremely clean dictates the use of a fine-pore filter that may clog quickly. A large-capacity filter cannot be used because it would degrade the EC system frequency response. The high flow rate also requires a powerful vacuum pump, which will typically consume on the order of 1000 W. The analyzer must measure water vapor for spectroscopic and dilution corrections. Open-path analyzers are available for methane, but not for nitrous oxide. The currently available methane analyzers have low power consumption, but are very large. Their large size degrades frequency response and disturbs the air flow near the sonic anemometer. They require significant maintenance to keep the exposed multipass optical surfaces clean. Water vapor measurements for dilution and spectroscopic corrections require a separate water vapor analyzer. A new closed-path eddy covariance system for measuring nitrous oxide or methane fluxes provides an elegant solution. The analyzer (TGA200A, Campbell Scientific, Inc.) uses a thermoelectrically-cooled interband cascade laser. Its small sample-cell volume and unique sample-cell configuration (200 ml, 1.5 m single pass) provide excellent frequency response with a low-power scroll pump (240 W). A new single-tube Nafion® dryer removes most of the water vapor, and attenuates fluctuations in the residual water vapor. Finally, a vortex intake assembly eliminates the need for an intake filter without adding volume that would degrade system frequency response. Laboratory testing shows the system attenuates the water vapor dilution term by more than 99% and achieves a half-power band width of 3.5 Hz.

  16. Percolation threshold near the second phase transition in diluted system of Gd2-x(La, Y)xIn

    International Nuclear Information System (INIS)

    In this paper it is demonstrated that the second phase transition of Gd2In intermetallic compound gets eliminated by diluting Gd2-x(LaY)xIn at a critical composition of x=0.5. The exchange coupling for intra-cluster interactions is estimated in the correlation ranges of 3.3 ACC>4 A where the correlation length is defined as RC=kF|R→i-R→j|. The sign and strength of the exchange coupling are identified by the eigenvalues λ(k) and are obtained from zeros of the 4x4 matrix of JijRR' along the three directions of the reciprocal lattice for each dilution (x=0.25, 0.5, 0.75, 1). The transition temperature is calculated using the minimum eigenvalue λmin (k=0, π) which agrees with the experiment. Magnetic field and temperature dependence of the magnetization and electrical resistivity measurements show that: (i) Elimination of the AFM phase is caused by breaking of some FM short-range exchange couplings, and (ii) Conduction electrons order antiferromagnetically at low temperatures and ferromagnetically at high temperatures.

  17. Effects of Bio-sludge Concentration and Dilution Rate on the Efficiency of Sequencing Batch Reactor (SBR System for Textile Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    Suntud Sirianuntapiboon

    2012-06-01

    Full Text Available The color removal efficiency of a sequencing batch reactor (SBR system with synthetic textile wastewater (STWW containing 80 mg/L disperse dye increased with the increase of mixed liquor suspended solids (MLSS or solids retention time (SRT. The color removal efficiency was over 98% at an MLSS of 4,000 mg/L and SRT of over 25 days. Also, the color removal efficiency decreased with the increase of dye concentration. Both disperse blue 60 and disperse red 60 repressed the growths and activities of both heterotrophic and denitrifying bacteria, but they did not show any effect on nitrifying bacteria. However, the SBR system did not show any change in color removal efficiency of both disperse red 60 and disperse blue 60. The SBR system showed quite low color, COD and BOD5 removal efficiencies with raw textile wastewater (TWW. But, the system removal efficiencies could be increased by dilution of the TWW and supplementation with glucose. The color removal efficiency of the system with four times diluted-TWW containing 1.875 g/L glucose was 69.6±4.0%. Moreover, contaminated-NaCl in STWW could depress color adsorption yields of living as well as dead bio-sludge.

  18. Annealing behavior of ultrathin Mo layer located at interface or on surface of Ti-Si system

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Annealing behavior, at different annealing temperatures, of an ultrathin Mo layer located between a Ti film and Si substrate or deposited on the top of sur face of a Ti film was investigated by Rutherford backscattering spectrometry (RBS), cross-sectional transmission electron microscopy (TEM) and energy dispersive X-ray spectrometry (EDS). In a Ti/Mo/Si structure, partially reacted film with layer struc ture of Ti-rich silicide/TiSi2/(Mo, Ti)Si2 on a Si substrate was formed after 550℃ annealing for 30 min. The ratio of Mo to Ti in (Mo, Ti)Si2 layer decreases from near Si substrate upwards and becomes zero at about 20 nm away. In a Mo/Ti/Si structure, the surface Mo layer enhances the Si diffusion from the substrate during annealing. Mo bearing Ti rich silicide exists on the surface until 600℃ and then converts to (Mo, Ti)Si2 after 650℃ annealing, and the atomic ratio of Mo to Ti decreases from the top surface into Ti silicide film, and becomes zero at about 30 nm away from the surface. In both cases of interface Mo and surface Mo layer, the atomic ratio of Mo to Ti in the region of (Mo, Ti)Si2 was found to be very low, with an average value of less than 0.2. Low content of Mo in Mo containing ternary silicide leads easily to the formation of the stable phase of C54 (Mo, Ti)Si2, which acts as a template for the formation of C54 TiSi2 beneath when Mo is deposited on the surface.

  19. Hysteresis in IMC systems of AB2-H2 type. Effect of IMC composition, hydrogen concentration in solid phase and annealing

    International Nuclear Information System (INIS)

    Thermodynamic parameters of hysteresis in AB2-H2 systems were determined by equilibrium-calorimetric method. Concentration dependences of formation and decomposition heats of hydrides are presented. Sorption and desorption isotherms were obtained for four IMC: ZrCrMn, ZrMn2, Zr0.8Mn0.2Mn2 at 293 K. All investigated systems demonstrate sufficient hysteresis in sorption and desorption pressures in two-phase region. Effect of annealing on hysteresis and inclination of pressure plateau was investigated, taking Zr0.8Mn0.2Mn2 system as an example

  20. Identification of differentially expressed genes using an annealing control primer system in stage III serous ovarian carcinoma

    International Nuclear Information System (INIS)

    Most patients with ovarian cancer are diagnosed with advanced stage disease (i.e., stage III-IV), which is associated with a poor prognosis. Differentially expressed genes (DEGs) in stage III serous ovarian carcinoma compared to normal tissue were screened by a new differential display method, the annealing control primer (ACP) system. The potential targets for markers that could be used for diagnosis and prognosis, for stage III serous ovarian cancer, were found by cluster and survival analysis. The ACP-based reverse transcriptase polymerase chain reaction (RT PCR) technique was used to identify DEGs in patients with stage III serous ovarian carcinoma. The DEGs identified by the ACP system were confirmed by quantitative real-time PCR. Cluster analysis was performed on the basis of the expression profile produced by quantitative real-time PCR and survival analysis was carried out by the Kaplan-Meier method and Cox proportional hazards multivariate model; the results of gene expression were compared between chemo-resistant and chemo-sensitive groups. A total of 114 DEGs were identified by the ACP-based RT PCR technique among patients with stage III serous ovarian carcinoma. The DEGs associated with an apoptosis inhibitory process tended to be up-regulated clones while the DEGs associated with immune response tended to be down-regulated clones. Cluster analysis of the gene expression profile obtained by quantitative real-time PCR revealed two contrasting groups of DEGs. That is, a group of genes including: SSBP1, IFI6 DDT, IFI27, C11orf92, NFKBIA, TNXB, NEAT1 and TFG were up-regulated while another group of genes consisting of: LAMB2, XRCC6, MEF2C, RBM5, FOXP1, NUDCP2, LGALS3, TMEM185A, and C1S were down-regulated in most patients. Survival analysis revealed that the up-regulated genes such as DDAH2, RNase K and TCEAL2 might be associated with a poor prognosis. Furthermore, the prognosis of patients with chemo-resistance was predicted to be very poor when genes such

  1. Determination of performance criteria of safety systems in a nuclear power plant via simulated annealing optimization method

    International Nuclear Information System (INIS)

    This study presents and efficient methodology that derives design alternatives and performance criteria of safety functions/systems in commercial nuclear power plants. Determination of design alternatives and intermediate-level performance criteria is posed as a reliability allocation problem. The reliability allocation is performed for determination of reliabilities of safety functions/systems from top-level performance criteria. The reliability allocation is a very difficult multi objective optimization problem (MOP) as well as a global optimization problem with many local minima. The weighted Chebyshev norm (WCN) approach in combination with an improved Metropolis algorithm of simulated annealing is developed and applied to the reliability allocation problem. The hierarchy of probabilistic safety criteria (PSC) may consist of three levels, which ranges from the overall top level (e.g., core damage frequency, acute fatality and latent cancer fatality) through the interlnediate level (e.g., unavailiability of safety system/function) to the low level (e.g., unavailability of components, component specifications or human error). In order to determine design alternatives of safety functions/systems and the intermediate-level PSC, the reliability allocation is performed from the top-level PSC. The intermediated level corresponds to an objective space and the top level is related to a risk space. The reliability allocation is performed by means of a concept of two-tier noninferior solutions in the objective and risk spaces within the top-level PSC. In this study, two kinds of towtier noninferior solutions are defined: intolerable intermediate-level PSC and desirable design alternatives of safety functions/systems that are determined from Sets 1 and 2, respectively. Set 1 is obtained by maximizing simultaneously not only safety function/system unavailabilities but also risks. Set 1 reflects safety function/system unavailabilities in the worst case. Hence, the

  2. Isotope dilution mass spectrometry

    Science.gov (United States)

    Heumann, Klaus G.

    1992-09-01

    In the past isotope dilution mass spectrometry (IDMS) has usually been applied using the formation of positive thermal ions of metals. Especially in calibrating other analytical methods and for the certification of standard reference materials this type of IDMS became a routine method. Today, the progress in this field lies in the determination of ultra trace amounts of elements, e.g. of heavy metals in Antarctic ice and in aerosols in remote areas down to the sub-pg g-1 and sub-pg m-3 levels respectively, in the analysis of uranium and thorium at concentrations of a few pg g-1 in sputter targets for the production of micro- electronic devices or in the determination of sub-picogram amounts of230Th in corals for geochemical age determinations and of226Ra in rock samples. During the last few years negative thermal ionization IDMS has become a frequently used method. The determination of very small amounts of selenium and technetium as well as of other transition metals such as vanadium, chromium, molybdenum and tungsten are important examples in this field. Also the measurement of silicon in connection with a re-determination of Avogadro's number and osmium analyses for geological age determinations by the Re/Os method are of special interest. Inductively-coupled plasma mass spectrometry is increasingly being used for multi-element analyses by the isotope dilution technique. Determinations of heavy metals in samples of marine origin are representative examples for this type of multi-element analysis by IDMS. Gas chromatography-mass spectrometry systems have also been successfully applied after chelation of metals (for example Pt determination in clinical samples) or for the determination of volatile element species in the environment, e.g. dimethyl sulfide. However, IDMS--specially at low concentration levels in the environment--seems likely to be one of the most powerful analytical methods for speciation in the future. This has been shown, up to now, for species of

  3. Interdiffusion and growth of chromium silicide at the interface of Cr/Si(As) system during rapid thermal annealing

    International Nuclear Information System (INIS)

    In this work, the solid-state reaction between a thin film of chromium and silicon has been studied using Rutherford backscattering spectroscopy, X-ray diffraction and the sheet resistance measurements. The thickness of 100 nm chromium layer has been deposited by electronic bombardment on Si (100) substrates, part of them had previously been implanted with arsenic ions of 1015 at/cm2 doses and an energy of 100 keV. The samples were heat treated under rapid thermal annealing at 500 oC for time intervals ranging from 15 to 60 s. The rapid thermal annealing leads to a reaction at the interface Cr/Si inducing the formation and the growth of the unique silicide CrSi2, but no other phase can be detected. For samples implanted with arsenic, the saturation value of the sheet resistance is approximately 1.5 times higher than for the non-implanted case.

  4. Competitive diffusion of gold and copper in Cu/Au/Si and Au/Cu/Si annealed systems

    International Nuclear Information System (INIS)

    Full text.Thermal evaporation is used to deposit Au/Cu and Cu/Au bilayers on monocrystallin silicon substrates. The layers composition and surface morphology are performed as function of annealing temperature in the temperature range between 200 and 400 degre celsius using X-Ray diffraction, Rutherford backscattering spectroscopy and scanning electron microscopy. Independantly to the sequence of copper and gold deposition, Cu3Si and Cu4Si copper silicides result to the interdiffusion and reaction at the different interfaces. The 1000 A and 1200 A thicknesses of gold and copper diffusion barriers are insufficient to prevent the diffusion of copper and gold atoms respectively after an annealing of only 200 degre celsius

  5. Comparison of the Cathra Repliscan II, the AutoMicrobic system Gram-Negative General Susceptibility-Plus Card, and the Micro-Media System Fox Panel for dilution susceptibility testing of gram-negative bacilli.

    Science.gov (United States)

    Reiber, N E; Kelly, M T; Latimer, J M; Tison, D L; Hysmith, R M

    1985-06-01

    A comparative evaluation was done to test the accuracy of the Cathra Repliscan II agar dilution system (Diagnostic Equipment, Inc., St. Paul, Minn.), the AutoMicrobic system with Gram-Negative General Susceptibility-Plus Card (Vitek Systems, Inc., Hazelwood, Mo.), and the Micro-Media Fox Panel micro broth dilution system (Micro-Media Systems, Inc., San Jose, Calif.) in determining MICs of 12 antibiotics for 200 gram-negative bacilli. Of the 200 strains tested, 12 isolates did not grow in one of the three systems. The 188 remaining organisms included 158 members of the family Enterobacteriaceae, 20 Pseudomonas spp., 5 Acinetobacter sp., 3 Aeromonas spp., and 2 Vibrio spp. A total of 2,256 organism-antibiotic combinations were analyzed for each system. An MIC was considered correct if two of the three systems were in agreement. When disagreements occurred, correct MICs were determined by the standard agar dilution method. With this criterion, overall agreements of the Cathra Repliscan II system, AutoMicrobic system, and Micro-Media Fox Panel system were 94.7, 94.9, and 95.5%, respectively. Tetracycline (20%), nitrofurantoin (20%), and ampicillin (16%) accounted for 56% of the discrepancies observed. These results indicate that all three systems perform with a high degree of accuracy for susceptibility testing of gram-negative bacilli. PMID:4008625

  6. Generalized Simulated Annealing

    OpenAIRE

    Tsallis, Constantino; Stariolo, Daniel A.

    1995-01-01

    We propose a new stochastic algorithm (generalized simulated annealing) for computationally finding the global minimum of a given (not necessarily convex) energy/cost function defined in a continuous D-dimensional space. This algorithm recovers, as particular cases, the so called classical ("Boltzmann machine") and fast ("Cauchy machine") simulated annealings, and can be quicker than both. Key-words: simulated annealing; nonconvex optimization; gradient descent; generalized statistical mechan...

  7. Simulated Quantum Annealing Can Be Exponentially Faster than Classical Simulated Annealing

    OpenAIRE

    Crosson, Elizabeth; Harrow, Aram W.

    2016-01-01

    Simulated Quantum Annealing (SQA) is a Markov Chain Monte-Carlo algorithm that samples the equilibrium thermal state of a Quantum Annealing (QA) Hamiltonian. In addition to simulating quantum systems, SQA has also been proposed as another physics-inspired classical algorithm for combinatorial optimization, alongside classical simulated annealing. However, in many cases it remains an open challenge to determine the performance of both QA and SQA. One piece of evidence for the strength of Q...

  8. Polysaccharide-based polyanion--polycation--polyanion ternary systems. A preliminary analysis of interpolyelectrolyte interactions in dilute solutions.

    Science.gov (United States)

    Donati, Ivan; Feresini, Massimo; Travan, Andrea; Marsich, Eleonora; Lapasin, Romano; Paoletti, Sergio

    2011-11-14

    The present contribution deals with the preparation and characterization of ternary mixtures of polysaccharides with potential applications in the field of tissue engineering. Two natural polyanions, i.e., alginate and hyaluronic acid, and a polycation, a lactose-modified chitosan (chitlac), were mixed in dilute conditions. The miscibility between the three components was explored in the presence of different amounts of supporting simple salt. These analyses allowed to identify the experimental conditions avoiding polymer phase separation and leading to either solution of independent polymers or soluble nonstoichiometric interpolyelectrolyte complexes. The characterization of the interpolyelectrolyte complexes was tackled by means of viscometry, light scattering, fluorescence quenching, and energy transfer. The electrostatic interactions taking place among the different polyelectrolytes led to synergistic effects on the viscosity of the polymer mixtures which strongly depend on the ionic strength. It has been found that, starting from binary soluble complexes of alginate and chitlac, the addition of hyaluronan led to the dissolution of the complexes. At variance, the addition of alginate to a phase-separated binary mixture of hyaluronan and chitlac led to the formation of soluble complexes composed of all three polysaccharides and, eventually, to their dissolution. In addition, the results showed that at low ionic strength the overall properties of the ternary mixtures depend on their order of mixing. PMID:21995461

  9. Investigation on the strain of SiGe/Si heteroepitaxial system during high temperature annealing by RBS/Channeling

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The influence of the high temperature processing on the strain stored in SiGe hetero epilayer was studied by means of RBS/Channeling. Channeling angularscan along the < 110 > axial direction in the (100) plane was used to characterize the tetragonal distortion in the SiGe strained layer. The strained crystal structure parameters were acquired by combining the determination of strain with the elasticity theory. It is shown that the strain stored in the SiGe epilayer has significantly change (relaxation factor from 0.023 to 0.84) after high temperature annealing. The potential strain relaxation mechanisms were discussed.

  10. On lumped models for thermodynamic properties of simulated annealing problems

    OpenAIRE

    Andresen, Bjarne; Hoffmann, Karl Heinz; Mosegaard, Klaus; Nulton, Jim; Pedersen, Jacob Mørch; Salamon, Peter

    1988-01-01

    The paper describes a new method for the estimation of thermodynamic properties for simulated annealing problems using data obtained during a simulated annealing run. The method works by estimating energy-to-energy transition probabilities and is well adapted to simulations such as simulated annealing, in which the system is never in equilibrium.

  11. Continuously operating dilution refrigerator with adsorption pumps

    International Nuclear Information System (INIS)

    The main parts and performance of two versions of the continuously operating dilution refrigerator with an adsorption pumping system dedicated to physical investigations at ultralow temperatures are described. Compared to conventional dilution refrigerators these versions are more compact, economic and more vibration proof. This type of dilution refrigerator allows a single shot operation to be realized. The minimum temperature reached in a single continuous heat exchanger refrigerator is 18 mK for a continuous operation and 5 - 8 mK for a single shot are. On addition of four discrete heat exchangers, the minimum temperature for continuous operation reduces down to 8 mK

  12. Dilution, Concentration, and Flotation

    Science.gov (United States)

    Liang, Ling; Schmuckler, Joseph S.

    2004-01-01

    As both classroom teaching practice and literature show, many students have difficulties learning science concepts such as density. Here are some investigations that identify the relationship between density and floating through experimenting with successive dilution of a liquid, or the systematic change of concentration of a saltwater solution.…

  13. Evaluating impact of market changes on increasing cell-load variation in dynamic cellular manufacturing systems using a hybrid Tabu search and simulated annealing algorithms

    Directory of Open Access Journals (Sweden)

    Aidin Delgoshaei

    2016-06-01

    Full Text Available In this paper, a new method is proposed for scheduling dynamic cellular manufacturing systems (D-CMS in the presence of uncertain product demands. The aim of this method is to control the process of trading off between in-house manufacturing and outsourcing while product demands are uncertain and can be varied from period to period. To solve the proposed problem, a hybrid Tabu Search and Simulated Annealing are developed to overcome hardness of the proposed model and then results are compared with a Branch and Bound and Simulated Annealing algorithms. A Taguchi method (L_27 orthogonal optimization is used to estimate parameters of the proposed method in order to solve experiments derived from literature. An in-depth analysis is conducted on the results in consideration of various factors. For evaluating the system imbalance in dynamic market demands, a new measuring index is developed. Our findings indicate that the uncertain condition of market demands affects the routing of product parts and may induce machine-load variations that yield to cell-load diversity. The results showed that the proposed hybrid method can provide solutions with better quality.

  14. General Simulated Annealing

    Institute of Scientific and Technical Information of China (English)

    姚新; 李国杰

    1991-01-01

    Simulated annealing is a new kind of random search methods developed in recent years.It can also be considered as an extension to the classical hill-climbing method in AI--probabilistic hill-cimbing.One of its most important features is its global convergence.The convergence of simulated annealing algorithm is determined by state generating probability,state accepting probability,and temperature decreasing rate,This paper gives a generalized simulated annealing algorithm with dynamic generating and accepting probabilities.The paper also shows that the generating and accepting probabilities can adopt many different kinds of distributions while the global convergence is guaranteed.

  15. Moessbauer-spectroscopic study of structure and magnetism of the exchange-coupled layer systems Fe/FeSn2, and Fe/FeSi/Si and the ion-implanted diluted magnetic semiconductor SiC(Fe)

    International Nuclear Information System (INIS)

    In line with this work the strucural and magnetic properties of the exchange coupled layered systems Fe/FeSn2 and Fe/FeSi/Si and of the Fe ion implanted diluted magnetic semiconductor (DMS) SiC(Fe) were investigated. The main measuring method was the isotope selective 57Fe conversion electron Moessbauer spectroscopy (CEMS), mostly in connection with the 57Fe tracer layer technique, in a temperature range from 4.2 K to 340 K. Further measurement techniques were X-ray diffraction (XRD), electron diffraction (LEED, RHEED), SQUID magnetometry and FMR (Ferromagnetic Resonance). In the first part of this work the properties of thin AF FeSn2(001) films and of the exchange-bias system Fe/FeSn2(001) on InSb(001) were investigated. With the application of 57Fe-tracer layers and CEMS both the Fe-spin structure and the temperature dependence of the magnetic hyperfine field (Bhf) of FeSn2 could be examined. The evaporation of Fe films on the FeSn2 films produced in the latter ones a high perpendicular spin component at the Fe/FeSn2 interface. In some distance from the interface the Fe spins rotate back into the sample plane. Furthermore 57Fe-CEMS provided a correlation between the absolute value of the exchange field vertical stroke He vertical stroke and the amount of magnetic defects within the FeSn2. Temperature dependent CEMS-measurements yielded informations about the spin dynamics within the AF. The transition temperatures TB*, which were interpreted as superparamagnetic blocking temperatures, obtain higher values compared to the temperatures TB of the exchange-bias effect, obtained with magnetometry measurements. The second part of this work deals with the indirect exchange coupling within Fe/FeSi/Si/FeSi/Fe multilayers and FeSi diffusion barriers. The goal was to achieve Fe free Si interlayers. The CEMS results show that starting from a thickness of tFeSi=10-12 A of the ''lower'' FeSi layers the interdiffusion of Fe is inhibited. For thicker FeSi layers (tFeSi ∼ 20 A

  16. Dilution-based emissions sampling from stationary sources: Part 2--Gas-fired combustors compared with other fuel-fired systems.

    Science.gov (United States)

    England, Glenn C; Watson, John G; Chow, Judith C; Zielinska, Barbara; Chang, M C Oliver; Loos, Karl R; Hidy, George M

    2007-01-01

    With the recent focus on fine particle matter (PM2.5), new, self-consistent data are needed to characterize emissions from combustion sources. Such data are necessary for health assessment and air quality modeling. To address this need, emissions data for gas-fired combustors are presented here, using dilution sampling as the reference. The dilution method allows for collection of emitted particles under conditions simulating cooling and dilution during entry from the stack into the air. The sampling and analysis of the collected particles in the presence of precursor gases, SO2 nitrogen oxide, volatile organic compound, and NH3 is discussed; the results include data from eight gas fired units, including a dual-fuel institutional boiler and a diesel engine powered electricity generator. These data are compared with results in the literature for heavy-duty diesel vehicles and stationary sources using coal or wood as fuels. The results show that the gas-fired combustors have very low PM2.5 mass emission rates in the range of approximately 10(-4) lb/million Btu (MMBTU) compared with the diesel backup generator with particle filter, with approximately 5 x 10(-3) lb/MMBTU. Even higher mass emission rates are found in coal-fired systems, with rates of approximately 0.07 lb/MMBTU for a bag-filter-controlled pilot unit burning eastern bituminous coal. The characterization of PM2.5 chemical composition from the gas-fired units indicates that much of the measured primary particle mass in PM2.5 samples is organic or elemental carbon and, to a much less extent, sulfate. Metal emissions are quite low compared with the diesel engines and the coal- or wood-fueled combustors. The metals found in the gas-fired combustor particles are low in concentration, similar in concentration to ambient particles. The interpretation of the particulate carbon emissions is complicated by the fact that an approximately equal amount of particulate carbon (mainly organic carbon) is found on the

  17. Nested Quantum Annealing Correction

    OpenAIRE

    Vinci, Walter; Albash, Tameem; Lidar, Daniel A.

    2015-01-01

    We present a general error-correcting scheme for quantum annealing that allows for the encoding of a logical qubit into an arbitrarily large number of physical qubits. Given any Ising model optimization problem, the encoding replaces each logical qubit by a complete graph of degree $C$, representing the distance of the error-correcting code. A subsequent minor-embedding step then implements the encoding on the underlying hardware graph of the quantum annealer. We demonstrate experimentally th...

  18. Annealing of Solar Cells and Other Thin Film Devices

    Science.gov (United States)

    Escobar, Hector; Kuhlman, Franz; Dils, D. W.; Lush, G. B.; Mackey, Willie R. (Technical Monitor)

    2001-01-01

    Annealing is a key step in most semiconductor fabrication processes, especially for thin films where annealing enhances performance by healing defects and increasing grain sizes. We have employed a new annealing oven for the annealing of CdTe-based solar cells and have been using this system in an attempt to grow US on top of CdTe by annealing in the presence of H2S gas. Preliminary results of this process on CdTe solar cells and other thin-film devices will be presented.

  19. A Compact Safe Cold-Start (CS2) System for Scramjets using Dilute Triethylaluminum Fuel Mixtures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal addresses the cold-start requirements of scramjet engines by developing a safe, energy-dense, and low volume hydrocarbon fuel conditioning system...

  20. A Compact Safe Cold-Start (CS2) System for Scramjets using Dilute Triethylaluminum Fuel Mixtures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal leverages a highly successful Phase 1 feasibility effort to further develop a system that satisfies the cold-start requirements of scramjet engines....

  1. The leiden dilution refrigerator

    International Nuclear Information System (INIS)

    In march 1971, the author constructed the first version of a new type of 3He-4He dilution refrigerator through which, in contrast with the conventional dilution refrigerator, 4He instead of 3He is circulated. It is possible to keep the 4He circulation entirely at low temperatures, by using the fountain effect in superfluid 4He. The most important advantage of this refrigerator is that the precooling of nearly pure 3He simply takes place in one (spiralled or straight) capillary through which both liquid helium phases flow in opposite directions, driven by the force of gravity. Heat exchangers with their often complicated technical constructions are avoided. The lowest temperature that can be achieved in the refrigerator is about 5 mK. In this thesis, experiments with and a thermodynamic analysis of this refrigerator are described

  2. Multi-Channel Auto-Dilution System for Remote Continuous Monitoring of High Soil-CO2 Fluxes

    Energy Technology Data Exchange (ETDEWEB)

    Amonette, James E.; Barr, Jonathan L.

    2009-04-23

    Geological sequestration has the potential capacity and longevity to significantly decrease the amount of anthropogenic CO2 introduced into the atmosphere by combustion of fossil fuels such as coal. Effective sequestration, however, requires the ability to verify the integrity of the reservoir and ensure that potential leakage rates are kept to a minimum. Moreover, understanding the pathways by which CO2 migrates to the surface is critical to assessing the risks and developing remediation approaches. Field experiments, such as those conducted at the Zero Emissions Research and Technology (ZERT) project test site in Bozeman, Montana, require a flexible CO2 monitoring system that can accurately and continuously measure soil-surface CO2 fluxes for multiple sampling points at concentrations ranging from background levels to several tens of percent. To meet this need, PNNL is developing a multi-port battery-operated system capable of both spatial and temporal monitoring of CO2 at concentrations from ambient to at least 150,000 ppmv. This report describes the system components (sampling chambers, measurement and control system, and power supply) and the results of a field test at the ZERT site during the late summer and fall of 2008. While the system performed well overall during the field test, several improvements to the system are suggested for implementation in FY2009.

  3. Conversion of organic solid waste to hydrogen and methane by two-stage fermentation system with reuse of methane fermenter effluent as diluting water in hydrogen fermentation.

    Science.gov (United States)

    Jung, Kyung-Won; Moon, Chungman; Cho, Si-Kyung; Kim, Sang-Hyoun; Shin, Hang-Sik; Kim, Dong-Hoon

    2013-07-01

    In this study, a two-stage system converting organic solid waste (food waste+sewage sludge) to H2 and CH4 was operated. In the first stage of dark fermentative hydrogen production (DFHP), a recently proposed method that does not require external inoculum, was applied. In the second stage, anaerobic sequencing batch reactor (ASBR) and an up-flow anaerobic sludge blanket reactor (UASBr) were followed to treat H2 fermenter effluent. (H2+CH4-ASBR) system showed better performance in terms of total biogas conversion (78.6%), while higher biogas production rate (2.03 L H2/Lsystem/d, 1.96 L CH4/Lsystem/d) was achieved in (H2+CH4-UASBr) system. To reduce the alkali addition requirement in DFHP process, CH4 fermenter effluent was tested as a diluting water. Both the ASBR and UASBr effluent was effective to keep the pH above 6 without CH4 production. In case of using ASBR effluent, H2 production dropped by 15%, but alkali addition requirement was reduced by 50%. PMID:23648761

  4. Morphology of interior interfaces in dilute nitride III/V material systems; Morphologie innerer Grenzflaechen in verduennt stickstoffhaltigen III/V-Materialsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Oberhoff, S.

    2007-12-03

    This study aims to clarify structure formation processes in dilute N-containing III/V-based material systems, using highly selective etching methods and subsequent atomic force microscopy (AFM) to expose and analyse interior interfaces. In the first part of this study it was directly proved for the first time that adding Sb during growth interruption inhibits the GI-induced structural phase transition and reduces the diffusivity on GaAs and (GaIn)(NAs) surfaces. However, applying Sb during GI does not affect the driving force of the structural phase transition. Therefore a fundamental analysis about the incorporation of Sb into GaAs, Ga(NAs) and (GaIn)(NAs) was carried out in the second part of the study. Using a combination of high resolution X-ray diffraction, transmission electron microscopy and SIMS measurements, it was verified that incorporating Sb into (GaIn)(NAs) causes an increase of the In content and a decrease of the N content. In the third part of the study, novel etching methods for the GaP-based material system Ga(NAsP) are introduced which provide the opportunity to analyse structure formation processes on interior interfaces in this material system by AFM. (orig.)

  5. Generalization of the Lifshitz–Slyozov–Wagner coarsening theory to non-dilute multi-component systems

    International Nuclear Information System (INIS)

    The coarsening of precipitates in a matrix with a non-zero volume fraction is treated by assuming that the exchange of matter between the precipitates occurs by diffusion in the matrix within finite zones surrounding the precipitates. The thermodynamic extremal principle is used for the derivation of evolution equations for the precipitate radii. Accordingly, non-steady-state and steady-state distribution functions are deduced, depending on the system parameter characterizing the finite diffusion zones. The distribution functions tend exactly to the established Lifshitz–Slyozov–Wagner distribution for a zero volume fraction of the precipitates. The steady-state distribution functions are expressed by means of distinct volume-fraction-dependent parameters, which are presented by analytical expressions and in diagrams. To treat non-steady-state systems, ensembles of up to 106 precipitates can easily be handled by standard computational methods

  6. Is Dilution The Solution To Pollution? Municipal Sewerage Systems In Late Nineteenth Century San Francisco And London

    OpenAIRE

    Smith, Brooke Ray

    2007-01-01

    This article explores the historical development of wastewater management planning in two cities: San Francisco and London. Both cities constructed their municipal sewerage networks in the late 1800s, and both cities designed these networks as combined systems, which carry storm water and sewer water in the same pipes. Due to differences in political and public attitudes towards sewage management and to the relative status of engineers versus scientists, London and San Francisco followed diff...

  7. A pH-responsive and magnetically separable dynamic system for efficient removal of highly dilute antibiotics in water.

    Science.gov (United States)

    Liu, Wanpeng; Ma, Jianqing; Shen, Chensi; Wen, Yuezhong; Liu, Weiping

    2016-03-01

    In order to control the antibiotic-related crisis and reduce the negative impacts on the environment and human health, it is urgent to develop effective technologies to eliminate residual antibiotics in water. Herein, we successfully fabricated a novel, pH-responsive and magnetically separable dynamic system for micropollutant adsorption and oxidation degradation in graphene oxide (GO)/nanoscale zero-valent iron (nZVI) composite with macroscopic structure. The pH-responsive self-assembly behavior of GO/nZVI composite was explored. The macroscopic structure of GO/nZVI composite serves as an excellent adsorbent for antibiotic removal in water. The adsorption process is fast and highly efficient even in high salty and humic acid containing water under acid to neutral conditions. After removal antibiotics, GO/nZVI composite is conveniently separated by magnetic system and put into alkaline solution (pH > 9) for adsorbent regeneration. Interestingly, it is found that at pH > 9, GO/nZVI composite disassembles partly upon increasing pH values, leading to the elution of antibiotics for efficient antibiotics degradation by ozonization. More importantly, this pH-responsive GO/nZVI system exhibits high removal efficiency, high stability, reusability and easily separation, making it a promising method for treatment of water with micropollutants. PMID:26724436

  8. Temperature control during annealing

    International Nuclear Information System (INIS)

    Temperature control at a weld between a tube and tube plate having heat input from an inductive heating probe to effect annealing of the weld is performed with the aid of a signal generating receptor coil coupled with the probe. The signal from the coil experiences a characteristic change when the temperature of the weld reaches the required annealing temperature and this signal is used to control the heat input to the weld. The receptor coil can be inside the tube, outside the tube, embracing a number of similar tubes, or may be inside an adjacent tube. At the required anneal temperature, the materials of the tube and weld reach their Curie point which brings about a permeability change. (author)

  9. Diluted magnetic semiconductors

    CERN Document Server

    Jain, Mukesh

    1991-01-01

    This review volume presents both basic and applied aspects of diluted magnetic semiconductors (DMS). The term DMS applies generally to semiconductors in which a fraction of its constituent ions are replaced by magnetic ions. This book is only the second to review DMS materials. It presents a detailed treatment of the current state of knowledge of the established properties of DMS in the form of single crystals, quantum wells and superlattices. It also brings together recent work on new DMS materials and presents discussions on a wide range of possible DMS applications.

  10. Transfer of phosphorus in soil-plant and soil-solution systems using isotopic labeling and dilution methods

    International Nuclear Information System (INIS)

    A mechanistically-based characterization of plant-available soil P was obtained by labelling the isotopically exchangeable P and comparing, after similar periods, either the isotopic composition of P taken up by plants or the isotopic composition of P ions in soil suspensions (1 g:10 mL). The isotopic composition data did not differ significantly for different soil-solution-plant-fertilizer systems. As a consequence, plant-available soil P can be identified with the isotopically exchangeable P, i.e. soil P that has the same isotopic composition as P in solution. As a consequence, a deterministic modelling of P-ion transfer between soil and solution was developed using isotopic methods in soil suspensions for samples collected from a long-term field experiment conducted on P fertilization. The model, which is a kinetic Freundlich equation, accurately accounts for changes in the P concentration in solution and the periods of transfer. A laboratory procedure is proposed to quickly and easily determine the three-parameter estimates of the kinetic Freundlich equation. In this procedure, the range of P concentrations due to long-term P fertilization is mimicked by applying increasing rates of water-soluble P and by equilibrating these P-enriched soil suspensions before analyzing for P released to solution. The three-parameter estimates describing the soil-to-solution transfer of P ions were similar for all rates of laboratory-applied P. The modelling of the P-ion transfer is, therefore, independent of initial P concentration in solution. As a result, the time and soil-solution P dependence of the soil-to-solution transfer of P ions can be assessed by a simple and rapid laboratory procedure. (author)

  11. Measures of Fault Tolerance in Distributed Simulated Annealing

    OpenAIRE

    Prakash, Aaditya

    2012-01-01

    In this paper, we examine the different measures of Fault Tolerance in a Distributed Simulated Annealing process. Optimization by Simulated Annealing on a distributed system is prone to various sources of failure. We analyse simulated annealing algorithm, its architecture in distributed platform and potential sources of failures. We examine the behaviour of tolerant distributed system for optimization task. We present possible methods to overcome the failures and achieve fault tolerance for t...

  12. The effect of spin dilution on magnetism of the linear chain system -Cu2−ZnV2O7

    Indian Academy of Sciences (India)

    S N Bhatia; Niharika Mohapatra; R Nirmala; S K Malik

    2010-05-01

    We have measured the magnetic susceptibility () and heat capacity (p) of -Cu2−ZnV2O7 ( = 0, 0.05, 0.1, 0.15, 0.2, 0.3, 2) in the temperature range 2–300 K. A one-dimensional alternating exchange Heisenberg antiferromagnetism (HAF) is observed in all compositions with chains of infinite length. The intra-chain exchange remains uniform and decreases marginally with dilution of the magnetic state. A cooperative ordering is seen in the magnetic chains for all Zn concentrations ( ≤ 0.3). The temperature of occurrence of this transition decreases with increasing Zn concentration. Though the conventional spin-wave theory has been used here to describe the properties of the ordered phase, the presence of some contributions like the lattice heat capacity in p and the Curie–Weiss term in susceptibility introduces some uncertainties in the estimation of the proportions contributed by the spin system. Therefore, the nature of the ordered phase could not be ascertained unambiguously.

  13. Measurement of N2 fixation in Sesbania aculeata pers. and Sorghum bicolor L. grown in intercropping system, under saline conditions, using 15N isotopic dilution technique

    International Nuclear Information System (INIS)

    A field experiment was conducted under saline conditions (soil ECe 15, water ECw 8 dS/m/m) to evaluate the performance of sole crops and inter crops of Sesbania aculeata and Sorghum bicolor (1:1 row ratio) in terms of dry matter production, total N yield, soil N uptake and N2-fixation using 15N isotope dilution method. Dry matter yield in sole crop of sesbania was significantly higher that that of sole sorghum; whereas, that of the inter cropping was significantly lower than sole sesbania, but was similar to that produced by sole sorghum. Total nitrogen yield in sole sesbania was four-fold than that accumulated in sole sorghum, whereas, that of mixed cropping was 2.6 fold compared to that of sole sorghum. The LER of total N yield was higher than 1 reflecting a greater advantage of inter cropping system in terms of land use efficiency. The proportion of N derived from N2 fixation (%Ndfa) in the sesbania was increased from 63 to 79%, for sole and inter cropping system, respectively. There was no evidence of a significant transfer of N from the sesbania to the sorghum. Results on the relative growth of plants on saline soil compared with non-saline soil clearly demonstrated that sesbania was more salt tolerant than the sorghum. soil nitrogen uptake by plants, particularly in sorghum, was adversely affected by salinity. However, amounts of N2 fixed by sole sesbania grown is saline soil was close or even higher than on non-saline soil. The use of inter cropping systems of legumes and non-legumes could be a promising agricultural approach to reutilize wasted lands, after a careful selection of appropriate tolerant genotypes to prevailing saline conditions. (author)

  14. Measurement of N2 fixation in Sesbania aculeata and Sorghum bicolor L. grown in intercropping system using 15N isotopic dilution technique

    International Nuclear Information System (INIS)

    A field experiment on Sesbania aculeata and Sorghum bicolor grown in mono cropping and in inter cropping systems was conducted under non-saline conditions (soil ECe 0.16, water ECw1dS/m) to evaluate dry matter production, total N yield, soil N uptake and N2-fixation using 15N isotope dilution method. Three different row ratios of sesbania (ses) and sorghum (sor) were subjected in the inter cropping system (2ses: 1sot; 1ses: 1sor and 1ses: 2sor row ratio). Dry matter yield of sole sorghum was higher than that of sole sesbania, and it was similar to that produced by the inter cropping treatments. However, total N yield of sole sorghum was significantly the lowest, with no differences being obtained between sole sesbania and inter cropping treatments. The LERs of total N yield were, in all cases, higher than 1, reflecting a greater advantage of inter cropping system in terms of land use efficiency. Percentages of N2 fixation in the inter cropped sesbania were considerably enhanced compared with the pure stand of sesbania. This was mainly attributed to the depletion of soil N resulting from the greater apparent competitiveness of sorghum for soil N, and consequently, a greater dependence of sesbania on N2 fixation. However, the degree of the intraspecific competition for soil N uptake was affected by the proportion of crops in the mixture, and it was considerably reduced in the 2ses: 1sor row ratio. This was demonstrated when an equal depletion of soil and fertilizer N uptake occurred for both crops. We excluded in all-inter cropping treatments the possibility of N transfer from sesbania to sorghum. Row inter cropping, with crops grown in alternation of two rows of sesbania with one row of sorghum, seemed to be the most adequate row ratio in terms of total N yield, LER, N2-fixation and soil N uptake balance of the component crops. (author)

  15. A robust hybrid fuzzy-simulated annealing-intelligent water drops approach for tuning a distribution static compensator nonlinear controller in a distribution system

    Science.gov (United States)

    Bagheri Tolabi, Hajar; Hosseini, Rahil; Shakarami, Mahmoud Reza

    2016-06-01

    This article presents a novel hybrid optimization approach for a nonlinear controller of a distribution static compensator (DSTATCOM). The DSTATCOM is connected to a distribution system with the distributed generation units. The nonlinear control is based on partial feedback linearization. Two proportional-integral-derivative (PID) controllers regulate the voltage and track the output in this control system. In the conventional scheme, the trial-and-error method is used to determine the PID controller coefficients. This article uses a combination of a fuzzy system, simulated annealing (SA) and intelligent water drops (IWD) algorithms to optimize the parameters of the controllers. The obtained results reveal that the response of the optimized controlled system is effectively improved by finding a high-quality solution. The results confirm that using the tuning method based on the fuzzy-SA-IWD can significantly decrease the settling and rising times, the maximum overshoot and the steady-state error of the voltage step response of the DSTATCOM. The proposed hybrid tuning method for the partial feedback linearizing (PFL) controller achieved better regulation of the direct current voltage for the capacitor within the DSTATCOM. Furthermore, in the event of a fault the proposed controller tuned by the fuzzy-SA-IWD method showed better performance than the conventional controller or the PFL controller without optimization by the fuzzy-SA-IWD method with regard to both fault duration and clearing times.

  16. Standard dilution analysis.

    Science.gov (United States)

    Jones, Willis B; Donati, George L; Calloway, Clifton P; Jones, Bradley T

    2015-02-17

    Standard dilution analysis (SDA) is a novel calibration method that may be applied to most instrumental techniques that will accept liquid samples and are capable of monitoring two wavelengths simultaneously. It combines the traditional methods of standard additions and internal standards. Therefore, it simultaneously corrects for matrix effects and for fluctuations due to changes in sample size, orientation, or instrumental parameters. SDA requires only 200 s per sample with inductively coupled plasma optical emission spectrometry (ICP OES). Neither the preparation of a series of standard solutions nor the construction of a universal calibration graph is required. The analysis is performed by combining two solutions in a single container: the first containing 50% sample and 50% standard mixture; the second containing 50% sample and 50% solvent. Data are collected in real time as the first solution is diluted by the second one. The results are used to prepare a plot of the analyte-to-internal standard signal ratio on the y-axis versus the inverse of the internal standard concentration on the x-axis. The analyte concentration in the sample is determined from the ratio of the slope and intercept of that plot. The method has been applied to the determination of FD&C dye Blue No. 1 in mouthwash by molecular absorption spectrometry and to the determination of eight metals in mouthwash, wine, cola, nitric acid, and water by ICP OES. Both the accuracy and precision for SDA are better than those observed for the external calibration, standard additions, and internal standard methods using ICP OES. PMID:25599250

  17. Declining ecosystem health and the dilution effect.

    Science.gov (United States)

    Khalil, Hussein; Ecke, Frauke; Evander, Magnus; Magnusson, Magnus; Hörnfeldt, Birger

    2016-01-01

    The "dilution effect" implies that where species vary in susceptibility to infection by a pathogen, higher diversity often leads to lower infection prevalence in hosts. For directly transmitted pathogens, non-host species may "dilute" infection directly (1) and indirectly (2). Competitors and predators may (1) alter host behavior to reduce pathogen transmission or (2) reduce host density. In a well-studied system, we tested the dilution of the zoonotic Puumala hantavirus (PUUV) in bank voles (Myodes glareolus) by two competitors and a predator. Our study was based on long-term PUUV infection data (2003-2013) in northern Sweden. The field vole (Microtus agrestis) and the common shrew (Sorex araneus) are bank vole competitors and Tengmalm's owl (Aegolius funereus) is a main predator of bank voles. Infection probability in bank voles decreased when common shrew density increased, suggesting that common shrews reduced PUUV transmission. Field voles suppressed bank vole density in meadows and clear-cuts and indirectly diluted PUUV infection. Further, Tengmalm's owl decline in 1980-2013 may have contributed to higher PUUV infection rates in bank voles in 2003-2013 compared to 1979-1986. Our study provides further evidence for dilution effect and suggests that owls may have an important role in reducing disease risk. PMID:27499001

  18. Desynchronization in diluted neural networks

    International Nuclear Information System (INIS)

    The dynamical behavior of a weakly diluted fully inhibitory network of pulse-coupled spiking neurons is investigated. Upon increasing the coupling strength, a transition from regular to stochasticlike regime is observed. In the weak-coupling phase, a periodic dynamics is rapidly approached, with all neurons firing with the same rate and mutually phase locked. The strong-coupling phase is characterized by an irregular pattern, even though the maximum Lyapunov exponent is negative. The paradox is solved by drawing an analogy with the phenomenon of 'stable chaos', i.e., by observing that the stochasticlike behavior is 'limited' to an exponentially long (with the system size) transient. Remarkably, the transient dynamics turns out to be stationary

  19. New types of dilution refrigerator and space applications

    International Nuclear Information System (INIS)

    Dilution refrigerators are now commercially available with a lowest temperature of the order of 5 mK. However, for special applications, special purpose refrigerators are needed. After a presentation of the different possible ways to cool down by dilution of 3He in 4He, we discuss two designs that give more flexibility than the classical dilution refrigerators: (i) dilution refrigerators without 1 K pot; (ii) double still systems to allow a precooling by circulation of the mixture. In the second part, we compare the different possibilities to obtain low temperatures in space (T≤100 mK). Finally, we describe the dilution in open cycles which is presently the only dilution refrigerator insensitive to gravity. (orig.)

  20. The Trademark Dilution and Anti-dilution Protection

    Institute of Scientific and Technical Information of China (English)

    张欣月

    2015-01-01

    This paper,starting from the definition and expression of well-known trademark dilution,in developed countries for reference,on the basis of the trademark anti-dilution legislation,analyzes the problems existing in the trademark antidilution protection in China,and puts forward relevant legal suggestions.

  1. Bond-Dilution-Induced Quantum Phase Transitions in Heisenberg Antiferromagnets

    OpenAIRE

    Yasuda, Chitoshi; Todo, Synge; Takayama, Hajime

    2006-01-01

    Bond-dilution effects on the ground state of the square-lattice antiferromagnetic Heisenberg model, consisting of coupled bond-alternating chains, are investigated by means of the quantum Monte Carlo simulation. It is found that, when the ground state of the non-diluted system is a non-magnetic state with a finite spin gap, a sufficiently weak bond dilution induces a disordered state with a mid gap in the original spin gap, and under a further stronger bond dilution an antiferromagnetic long-...

  2. Analyses of beyond design basis accident homogeneous boron dilution scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Kereszturi, Andras; Hegyi, Gyoergy; Maraczy, Csaba; Trosztel, Istvan; Tota, Adam [Hungarian Academy of Sciences, Centre for Energy Research, Budapest (Hungary); Karsa, Zoltan [NUBIKI Nuclear Safety Research Institute, Ltd., Budapest (Hungary)

    2015-09-15

    Homogeneous boron dilution scenarios in a VVER-440 reactor were analyzed using the coupled KIKO3D-ATHLET code. The scenarios are named ''homogeneous'' because of the very slow dilution caused by a rupture in the heat exchanger of the makeup system. Without the presented analyses, a significant contribution of the homogeneous boron dilution to the Core Damage Frequency (CDF) had to be assumed in the Probabilistic Safety Analyses (PSA). According to the combined results of the presented deterministic and probabilistic analyses, the final conclusion is that boron dilution transients don't give significant contribution to the CDF for the investigated VVER-440 NPP.

  3. Analyses of beyond design basis accident homogeneous boron dilution scenarios

    International Nuclear Information System (INIS)

    Homogeneous boron dilution scenarios in a VVER-440 reactor were analyzed using the coupled KIKO3D-ATHLET code. The scenarios are named ''homogeneous'' because of the very slow dilution caused by a rupture in the heat exchanger of the makeup system. Without the presented analyses, a significant contribution of the homogeneous boron dilution to the Core Damage Frequency (CDF) had to be assumed in the Probabilistic Safety Analyses (PSA). According to the combined results of the presented deterministic and probabilistic analyses, the final conclusion is that boron dilution transients don't give significant contribution to the CDF for the investigated VVER-440 NPP.

  4. An optimized buffer system for NMR-based urinary metabonomics with effective pH control, chemical shift consistency and dilution minimization.

    Science.gov (United States)

    Xiao, Chaoni; Hao, Fuhua; Qin, Xiaorong; Wang, Yulan; Tang, Huiru

    2009-05-01

    NMR-based metabonomics has been widely employed to understand the stressor-induced perturbations to mammalian metabolism. However, inter-sample chemical shift variations for metabolites remain an outstanding problem for effective data mining. In this work, we systematically investigated the effects of pH and ionic strength on the chemical shifts for a mixture of 9 urinary metabolites. We found that the chemical shifts were decreased with the rise of pH but increased with the increase of ionic strength, which probably resulted from the pH- and ionic strength-induced alteration to the ionization equilibrium for the function groups. We also found that the chemical shift variations for most metabolites were reduced to less than 0.004 ppm when the pH was 7.1-7.7 and the salt concentration was less than 0.15 M. Based on subsequent optimization to minimize chemical shift variation, sample dilution and maximize the signal-to-noise ratio, we proposed a new buffer system consisting of K(2)HPO(4) and NaH(2)PO(4) (pH 7.4, 1.5 M) with buffer-urine volume ratio of 1 : 10 for human urinary metabonomic studies; we suggest that the chemical shifts for the proton signals of citrate and aromatic signals of histidine be corrected prior to multivariate data analysis especially when high resolution data were employed. Based on these, an optimized sample preparation method has been developed for NMR-based urinary metabonomic studies. PMID:19381385

  5. Influence of annealing on spin state of cobalt ions inLa1-xSrxCoO3 (0≤x≤0.5) system

    Institute of Scientific and Technical Information of China (English)

    JIANG Lizhen; XU Zhuan

    2009-01-01

    Perovskite oxide La1-xSrxCoO3 (0≤x≤0.5) series were prepared and effect of oxygen annealing on crystal structure and magnetic susceptibility were studied. High-temperature susceptibility could be well fitted by Curie-Weiss law for all Sr-doped samples. Weiss constant and effective magnetic moment were determined, and their variations with Sr doping and oxygen annealing condition were obtained. The result suggested that by assuming that the Co3+ ions were in the intermediate-spin (IS) state, most of the Co4+ ions in the as-prepared samples might be in the high-spin (HS) state, but both the Co3+ and Co4+ ions might be in the IS state after oxygen annealing, which indicated that annealing in flowing oxygen could cause transition of the spin state of Co4+ ions from the HS state to IS state.

  6. Buffer erosion in dilute groundwater

    International Nuclear Information System (INIS)

    One scenario of interest for repository safety assessment involves the loss of bentonite buffer material in contact with dilute groundwater flowing through a transmissive fracture interface. In order to examine the extrusion/erosion behavior of bentonite buffer material under such circumstances, a series of experiments were performed in a flow-through, 1 mm aperture, artificial fracture system. These experiments covered a range of solution chemistry (salt concentration and composition), material composition (sodium montmorillonite and admixtures with calcium montmorillonite), and flow velocity conditions. No erosion was observed for sodium montmorillonite against solution compositions from 0.5 g/L to 10 g/L NaCl. No erosion was observed for 50/50 calcium/sodium montmorillonite against 0.5 g/L NaCl. Erosion was observed for both sodium montmorillonite and 50/50 calcium/sodium montmorillonite against solution compositions ≤ 0.25 g/L NaCl. The calculated erosion rates for the tests with the highest levels of measured erosion, i.e., the tests run under the most dilute conditions (ionic strength (IS) < ∼1 mM), were well-correlated to flow velocity, whereas the calculated erosion rates for the tests with lower levels of measured erosion, i.e., the tests run under somewhat less dilute conditions (∼1 mM < IS < ∼4 mM), were not similarly correlated indicating that material and solution composition can significantly affect erosion rates. In every experiment, both erosive and non-erosive, emplaced buffer material extruded into the fracture and was observed to be impermeable to water flowing in the fracture effectively forming an extended diffusive barrier around the intersecting fracture/buffer interface. Additionally, a model which was developed previously to predict the rate of erosion of bentonite buffer material in low ionic strength water in rock fracture environments was applied to three different cases: sodium montmorillonite expansion in a vertical tube, a

  7. Reactor pressure vessel thermal annealing

    International Nuclear Information System (INIS)

    The steel plates and/or forgings and welds in the beltline region of a reactor pressure vessel (RPV) are subject to embrittlement from neutron irradiation. This embrittlement causes the fracture toughness of the beltline materials to be less than the fracture toughness of the unirradiated material. Material properties of RPVs that have been irradiated and embrittled are recoverable through thermal annealing of the vessel. The amount of recovery primarily depends on the level of the irradiation embrittlement, the chemical composition of the steel, and the annealing temperature and time. Since annealing is an option for extending the service lives of RPVs or establishing less restrictive pressure-temperature (P-T) limits; the industry, the Department of Energy (DOE) and the Nuclear Regulatory Commission (NRC) have assisted in efforts to determine the viability of thermal annealing for embrittlement recovery. General guidance for in-service annealing is provided in American Society for Testing and Materials (ASTM) Standard E 509-86. In addition, the American Society of Mechanical Engineers (ASME) Code Case N-557 addresses annealing conditions (temperature and duration), temperature monitoring, evaluation of loadings, and non-destructive examination techniques. The NRC thermal annealing rule (10 CFR 50.66) was approved by the Commission and published in the Federal Register on December 19, 1995. The Regulatory Guide on thermal annealing (RG 1.162) was processed in parallel with the rule package and was published on February 15, 1996. RG 1.162 contains a listing of issues that need to be addressed for thermal annealing of an RPV. The RG also provides alternatives for predicting re-embrittlement trends after the thermal anneal has been completed. This paper gives an overview of methodology and recent technical references that are associated with thermal annealing. Results from the DOE annealing prototype demonstration project, as well as NRC activities related to the

  8. Corrosion characteristics of Zr-0.8Sn-0.4Fe-0.2Cr-xNb system with the variation of intermediate annealing temperature

    International Nuclear Information System (INIS)

    To investigate the effects of Nb content and annealing parameter on corrosion resistance in Zr-0.8Sn-0.4Fe-0.2Cr-xNb (x=0.1, 0.2, 0.4, 0.8%) alloys, corrosion tests have been carried out under the 400 degree C steam condition. The corrosion resistance of the alloys decreased with increasing the Nb content and the accumulated annealing parameter. But the Nb content in precipitates and the hydrogen pick-up fraction in matrix increased when the adding Nb content and the accumulated annealing parameter increased. The fraction of t-ZrO2 in oxide layers decreased with increasing the accumulated annealing parameter. It was concluded that the corrosion resistance of Zr-0.8Sn-0.4Fe-0.2Cr-xNb alloys could be controlled by the characteristics of (Zr, Nb)(Fe, Cr)2 type precipitates with the variation of the Nb content and the accumulated annealing parameter

  9. Burst annealing of high temperature GaAs solar cells

    Science.gov (United States)

    Brothers, P. R.; Horne, W. E.

    1991-01-01

    One of the major limitations of solar cells in space power systems is their vulnerability to radiation damage. One solution to this problem is to periodically heat the cells to anneal the radiation damage. Annealing was demonstrated with silicon cells. The obstacle to annealing of GaAs cells was their susceptibility to thermal damage at the temperatures required to completely anneal the radiation damage. GaAs cells with high temperature contacts and encapsulation were developed. The cells tested are designed for concentrator use at 30 suns AMO. The circular active area is 2.5 mm in diameter for an area of 0.05 sq cm. Typical one sun AMO efficiency of these cells is over 18 percent. The cells were demonstrated to be resistant to damage after thermal excursions in excess of 600 C. This high temperature tolerance should allow these cells to survive the annealing of radiation damage. A limited set of experiments were devised to investigate the feasibility of annealing these high temperature cells. The effect of repeated cycles of electron and proton irradiation was tested. The damage mechanisms were analyzed. Limitations in annealing recovery suggested improvements in cell design for more complete recovery. These preliminary experiments also indicate the need for further study to isolate damage mechanisms. The primary objective of the experiments was to demonstrate and quantify the annealing behavior of high temperature GaAs cells. Secondary objectives were to measure the radiation degradation and to determine the effect of repeated irradiation and anneal cycles.

  10. Positron lifetime study in dilute electron irradiated lead based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Moya, G. [Lab. de Physique des Materiaux, 13 Marseille (France); Li, X.H. [D.R.F.M., S.P.2.M., M.P., C.E.N.G., 38 Grenoble (France); Menai, A. [Lab. de Physique des Materiaux, 13 Marseille (France); Kherraz, M. [Lab. de Physique des Materiaux, 13 Marseille (France); Amenzou, H. [Lab. de Physique des Materiaux, 13 Marseille (France); Bernardini, J. [Lab. de Metallurgie, 13 Marseille (France); Moser, P. [D.R.F.M., S.P.2.M., M.P., C.E.N.G., 38 Grenoble (France)

    1995-06-01

    The recovery of defects in two dilute solute-lead based alloys (Pb-Au, Pb-Cd) has been followed by positron lifetime measurements after a 3 MeV electron irradiation at 20 K. Two distinct isochronal annealing stages, the first centred at about 150 K and the other around 275 K, are to be observed as exactly the same in both the pure Pb and dilute alloys but the vacancy clustering over the second stage seen in lead and Pb-Au is completely suppressed in the Pb-Cd alloy. The results are discussed in terms of a high interaction between the cadmium atoms and vacancies in agreement with a probable presence of atomic excitons. (orig.)

  11. Positron lifetime study in dilute electron irradiated lead based alloys

    International Nuclear Information System (INIS)

    The recovery of defects in two dilute solute-lead based alloys (Pb-Au, Pb-Cd) has been followed by positron lifetime measurements after a 3 MeV electron irradiation at 20 K. Two distinct isochronal annealing stages, the first centred at about 150 K and the other around 275 K, are to be observed as exactly the same in both the pure Pb and dilute alloys but the vacancy clustering over the second stage seen in lead and Pb-Au is completely suppressed in the Pb-Cd alloy. The results are discussed in terms of a high interaction between the cadmium atoms and vacancies in agreement with a probable presence of atomic excitons. (orig.)

  12. Positron lifetime study in dilute electron irradiated lead based alloys

    International Nuclear Information System (INIS)

    The recovery of defects in two dilute solute-lead based alloys (Pb-Au, Pb-Cd) has been followed by positron lifetime measurements after a 3 MeV electron irradiation at 20 K. Two distinct isochronal annealing stages, the first centered at about 150 K and the other around 275 K, are to be observed as exactly the same in both the pure Pb and dilute alloys but the vacancy clustering over the second stage seen in lead and Pb-Au is completely suppressed in the Pb-Cd alloy. The results are discussed in terms of a high interaction between the cadmium atoms and vacancies in agreement with a probable presence of atomic excitons. (authors). 3 figs., 9 refs

  13. Defect annealing in Mn/Fe-implanted TiO2(rutile)

    CERN Document Server

    Gunnlaugsson, H P; Masenda, H; Mølholt, T E; Johnston, K; Bharuth-Ram, K; Gislason, H; Langouche, G; Naidoo, D; Ólafsson, S; Svane, A; Weyer, G

    2014-01-01

    A study of the annealing processes and charge state of dilute Fe in rutile TiO2 single crystals was performed in the temperature range 143-662 K, utilizing online 57Fe emission Mossbauer spectroscopy following low concentrations ( 350 K.

  14. Immunological models in high dilution research following M Bastide.

    Science.gov (United States)

    Bonamin, Leoni Villano; Bellavite, Paolo

    2015-10-01

    In 1994, Madeleine Bastide described experimental models in immunology that were used during the 1980s to investigate high dilution effects on several biological systems. She classified the available papers in four categories: High dilutions of antigens; High dilutions of thymus, bursa and other hormones; High dilutions of cytokines; Immunopharmacological activity of silica. The studies about high dilutions of antigens were not continued after this period, but gave rise to a long process of a series of in vitro models on antigens and histamine dilutions, that led to the demonstration of the biological modulation effects of these preparations on basophil degranulation. During this process, a multi-centre study was performed, with a high degree of reproducibility among different independent laboratories. The studies about high diluted cytokines, thymulin and other hormones opened a new line of scientific investigation, about the regulatory properties of endogenous substances prepared according to homeopathic methods. The most frequently studied substance, thymulin, when administered to mice at 5cH potency, is able to improve the activity of phagocytes in different experimental situations, such as viral, bacterial and parasitic infections. The immunopharmacological activity of silica was demonstrated, at that time, as an in vivo illustration of the homeopathic 'similia principle'. More recently, studies on silica have assumed another focus: the putative role of silica as active contaminant present in high dilutions. This paper presents a follow-up summary on these items, considering the evolution of discoveries from 1994 to 2014. PMID:26678727

  15. Recontamination following dilute chemical decontamination

    International Nuclear Information System (INIS)

    Decontamination is beneficial in reducing radiation fields before inspection, maintenance, or repair work has to be performed on reactor systems. If the fields remain low at subsequent shutdowns, further benefit is attributable to the decontamination. Conversely, if fields rapidly become as high as before the decontamination, no residual benefit derives. In the case where the field rapidly becomes higher than before the decontamination, a detriment from the decontamination is experienced at subsequent shutdowns. In this paper the recontamination data following six separate dilute chemical decontaminations are reported for surveillance periods of up to two years. Surfaces operating at low temperature hardly recontaminated at all over the two-year period; surfaces exposed to high temperatures recontaminated to about 95% of their predecontamination level over a two-year period. A rapid recontamination rate for about three months following the decontamination was followed by recontamination at a rate which is significantly below the published rates for most BWRs in the USA, and for these two plants in particular. In all six cases studied, residual benefit from the decontamination was experienced at subsequent shutdowns. (author)

  16. multicast utilizando Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Yezid Donoso

    2005-01-01

    Full Text Available En este artículo se presenta un método de optimización multiobjetivo para la solución del problema de balanceo de carga en redes de transmisión multicast, apoyándose en la aplicación de la meta-heurística de Simulated Annealing (Recocido Simulado. El método minimiza cuatro parámetros básicos para garantizar la calidad de servicio en transmisiones multicast: retardo origen destino, máxima utilización de enlaces, ancho de banda consumido y número de saltos. Los resultados devueltos por la heurística serán comparados con los resultados arrojados por el modelo matemático propuesto en investigaciones anteriores.

  17. Nanostructured diluted magnetic semiconductors within mesoporous silica

    OpenAIRE

    Brieler, Felix

    2005-01-01

    In this work the successful formation of several diluted magnetic semiconductors inside various mesoporous host matrices is shown. For that purpose, different high quality mesoporous silicas were synthesised. Because of the possibility to obtain nanostructured quantum wires inside the respective pore systems, hexagonally ordered structures of the MCM-41 and SBA-15 kind were chosen as hosts for the intra-pore formation of the DMS nanoparticles. Later on it became obvious though, that the forma...

  18. Radiation annealing in cuprous oxide

    DEFF Research Database (Denmark)

    Vajda, P.

    1966-01-01

    Experimental results from high-intensity gamma-irradiation of cuprous oxide are used to investigate the annealing of defects with increasing radiation dose. The results are analysed on the basis of the Balarin and Hauser (1965) statistical model of radiation annealing, giving a square...

  19. Quantum Annealing of Hard Problems

    OpenAIRE

    Jorg, Thomas; Krzakala, Florent; Kurchan, Jorge; Maggs, A C

    2009-01-01

    Quantum annealing is analogous to simulated annealing with a tunneling mechanism substituting for thermal activation. Its performance has been tested in numerical simulation with mixed conclusions. There is a class of optimization problems for which the efficiency can be studied analytically using techniques based on the statistical mechanics of spin glasses.

  20. Reaction kinetics of annealing of high energy implantation by XRD

    International Nuclear Information System (INIS)

    The annealing of structural defects caused by high energy implantation is studied using X-ray diffraction. The implanted sample (dose: 1 x 1014 ions/cm2) was isochronally annealed in flowing nitrogen in steps of 50 K up to 823 K for 10 min each, using a RTA system developed in Mumbai University. XRD patterns were recorded after each annealing and analyzed for strain and curvature. Also, the screw dislocation density was estimated at each stage of annealing using the FWHM of w scans in high resolution mode. The XRD profiles were simulated using the dynamical theory of X-ray diffraction for layer damage i.e. thickness, mismatch with respect to substrate, Debye Waller factor and sample curvature. The activation energy and characteristic temperature of annealing were estimated through reaction kinetics, utilizing the experimental XRD for progressive changes with temperature, of strain and dislocation density

  1. Parameters Optimization of Low Carbon Low Alloy Steel Annealing Process

    Institute of Scientific and Technical Information of China (English)

    Maoyu ZHAO; Qianwang CHEN

    2013-01-01

    A suitable match of annealing process parameters is critical for obtaining the fine microstructure of material.Low carbon low alloy steel (20CrMnTi) was heated for various durations near Ac temperature to obtain fine pearlite and ferrite grains.Annealing temperature and time were used as independent variables,and material property data were acquired by orthogonal experiment design under intercritical process followed by subcritical annealing process (IPSAP).The weights of plasticity (hardness,yield strength,section shrinkage and elongation) of annealed material were calculated by analytic hierarchy process,and then the process parameters were optimized by the grey theory system.The results observed by SEM images show that microstructure of optimization annealing material are consisted of smaller lamellar pearlites (ferrite-cementite)and refining ferrites which distribute uniformly.Morphologies on tension fracture surface of optimized annealing material indicate that the numbers of dimple fracture show more finer toughness obviously comparing with other annealing materials.Moreover,the yield strength value of optimization annealing material decreases apparently by tensile test.Thus,the new optimized strategy is accurate and feasible.

  2. Rapid thermal annealing and crystallization mechanisms study of silicon nanocrystal in silicon carbide matrix

    OpenAIRE

    Wan Zhenyu; Huang Shujuan; Green Martin; Conibeer Gavin

    2011-01-01

    Abstract In this paper, a positive effect of rapid thermal annealing (RTA) technique has been researched and compared with conventional furnace annealing for Si nanocrystalline in silicon carbide (SiC) matrix system. Amorphous Si-rich SiC layer has been deposited by co-sputtering in different Si concentrations (50 to approximately 80 v%). Si nanocrystals (Si-NC) containing different grain sizes have been fabricated within the SiC matrix under two different annealing conditions: furnace anneal...

  3. Shock, Post-Shock Annealing, and Post-Annealing Shock in Ureilites

    Science.gov (United States)

    Rubin, Alan E.

    2006-01-01

    The thermal and shock histories of ureilites can be divided into four periods: 1) formation, 2) initial shock, 3) post-shock annealing, and 4) post-annealing shock. Period 1 occurred approx.4.55 Ga ago when ureilites formed by melting chondritic material. Impact events during period 2 caused silicate darkening, undulose to mosaic extinction in olivines, and the formation of diamond, lonsdaleite, and chaoite from indigenous carbonaceous material. Alkali-rich fine-grained silicates may have been introduced by impact injection into ureilites during this period. About 57% of the ureilites were unchanged after period 2. During period 3 events, impact-induced annealing caused previously mosaicized olivine grains to become aggregates of small unstrained crystals. Some ureilites experienced reduction as FeO at the edges of olivine grains reacted with C from the matrix. Annealing may also be responsible for coarsening of graphite in a few ureilites, forming euhedral-appearing, idioblastic crystals. Orthopyroxene in Meteorite Hills (MET) 78008 may have formed from pigeonite by annealing during this period. The Rb-Sr internal isochron age of approx.4.0 Ga for MET 78008 probably dates the annealing event. At this late date, impacts are the only viable heat source. About 36% of ureilites experienced period 3 events, but remained unchanged afterwards. During period 4, approx.7% of the ureilites were shocked again, as is evident in the polymict breccia, Elephant Moraine (EET) 83309. This rock contains annealed mosaicized olivine aggregates composed of small individual olivine crystals that exhibit undulose extinction. Ureilites may have formed by impact-melting chondritic material on a primitive body with heterogeneous O isotopes. Plagioclase was preferentially lost from the system due to its low impedance to shock compression. Brief melting and rapid burial minimized the escape of planetary-type noble gases from the ureilitic melts. Incomplete separation of metal from silicates

  4. Quantum annealing speedup over simulated annealing on random Ising chains

    CERN Document Server

    Zanca, Tommaso

    2015-01-01

    We show clear evidence of a speedup of a quantum annealing (QA) Schr\\"odinger dynamics over a Glauber master-equation simulated annealing (SA) for a random Ising model in one dimension. Annealings are tackled on equal footing, by a deterministic dynamics of the resulting Jordan-Wigner fermionic problems. We find that disorder, without frustration, makes both SA and real-time QA logarithmically slow in the annealing time $\\tau$, but QA shows a quadratic speedup with respect to SA. We also find that an imaginary-time Schr\\"odinger QA dynamics provides a further exponential speedup, with an asymptotic residual error compatible with a power-law $\\tau^{-\\mu}$.

  5. Single-length-scaling analysis for antiferromagnetic fractons in dilute Heisenberg system RbMn0.4Mg0.6F3

    International Nuclear Information System (INIS)

    The dynamic structure factors S(q,w) of an ideal percolating network, the three-dimensional (3d) dilute Heisenberg antiferromagnet RbMn0.4Mg0.6F3, obtained from high resolution (ΔE = 17.5 (micro)eV) inelastic neutron scattering (INS) experiments are analyzed for the first time within the framework of the single-length-scaling postulate (SLSP). The analysis confirms the validity of the SLSP and is also used to extract the values of the key exponents governing the spin dynamics, the dynamic exponent (zAF = Df/tildedAF) being 2.5 ± 0.1 and the spectral dimension tildedAF for antiferromagnetic (AFM) fractons taking a value of unity.

  6. Irradiation and annealing sensitivity studies

    International Nuclear Information System (INIS)

    This report describes an evaluation of foreign steel production made to US guidelines for improved radiation resistance (new vessel forms) and investigations on radiation sensitivity and post-irradiation annealing for embrittlement relief (vessels produced 1971 or earlier). In the study of foreign steels, investigations coordinated by the IAEA and involving steels produced by West Germany, France, and Japan have confirmed the adequacy of the US-developed specifications. Progress of the Irradiation-Anneal-Reirradiation investigations are described, noting the synergism between copper impurities and nickel alloying in radiation sensitivity and annealing response. The PVI Surveillance Dosimetry Improvement Program, which as primary application to the more radiation sensitive vessels, is also discussed

  7. Learning FCM by chaotic simulated annealing

    International Nuclear Information System (INIS)

    Fuzzy cognitive map (FCM) is a directed graph, which shows the relations between essential components in complex systems. It is a very convenient, simple, and powerful tool, which is used in numerous areas of application. Experts who are familiar with the system components and their relations can generate a related FCM. There is a big gap when human experts cannot produce FCM or even there is no expert to produce the related FCM. Therefore, a new mechanism must be used to bridge this gap. In this paper, a novel learning method is proposed to construct FCM by using Chaotic simulated annealing (CSA). The proposed method not only is able to construct FCM graph topology but also is able to extract the weight of the edges from input historical data. The efficiency of the proposed method is shown via comparison of its results of some numerical examples with those of Simulated annealing (SA) method.

  8. Analysis of heterogeneous boron dilution sequences

    International Nuclear Information System (INIS)

    In the scope of the international SETH project (focused on boron dilution sequences), the Spanish Nuclear Regulatory Commission (CSN) and the electric energy industry of Spain (UNESA) have promoted in Spain a national project for the analysis and application of the SETH results to the Spanish nuclear power plants. As part of this project, our team has performed a review and analysis of the different sequences that could lead to a boron dilution in the primary circuit of a pressurized water reactor (PWR). On a first stage of the project we have analyzed the different sequences and the phenomenologies that could lead to inadvertent boron dilution in the primary system (about twenty different sequences are described in the literature), the core damage frequency of each one, the projects and experiments carried out on several experimental facilities and the modifications performed in order to avoid or to mitigate this kind of sequences. On a second one we have reviewed the relation between the operating procedures, Westinghouse design reactors, and this kind of sequences. Finally we have analyzed the simulation problems of these kind of sequences and performed several numerical simulations with the TRAC-M (TRACE) code applied to numerical benchmarks and also to a 3D vessel model. (author)

  9. Stochastic Annealing for Variational Inference

    OpenAIRE

    Gultekin, San; Zhang, Aonan; Paisley, John

    2015-01-01

    We empirically evaluate a stochastic annealing strategy for Bayesian posterior optimization with variational inference. Variational inference is a deterministic approach to approximate posterior inference in Bayesian models in which a typically non-convex objective function is locally optimized over the parameters of the approximating distribution. We investigate an annealing method for optimizing this objective with the aim of finding a better local optimal solution and compare with determin...

  10. Dilution Refrigeration of Multi-Ton Cold Masses

    CERN Document Server

    Wikus, P; CERN. Geneva

    2007-01-01

    Dilution refrigeration is the only means to provide continuous cooling at temperatures below 250 mK. Future experiments featuring multi-ton cold masses require a new generation of dilution refrigeration systems, capable of providing a heat sink below 10 mK at cooling powers which exceed the performance of present systems considerably. This thesis presents some advances towards dilution refrigeration of multi-ton masses in this temperature range. A new method using numerical simulation to predict the cooling power of a dilution refrigerator of a given design has been developed in the framework of this thesis project. This method does not only allow to take into account the differences between an actual and an ideal continuous heat exchanger, but also to quantify the impact of an additional heat load on an intermediate section of the dilute stream. In addition, transient behavior can be simulated. The numerical model has been experimentally verified with a dilution refrigeration system which has been designed, ...

  11. Groundwater dilution and residence times, and constraints on chloride source, in the Mokai geothermal system, New Zealand, from chemical, stable isotope, tritium, and 36Cl data

    International Nuclear Information System (INIS)

    The maximum measured temperature of the production wells is near 323C at 2500 m depth, whereas temperatures in two wells on the northern margin of the upflow are 36Cl/Cl ratio of 2.6 x 10-15 and a 36Cl concentration of 106 atoms per 10-6 kg. This fluid has a lower ration (by a factor of 90) and a higher absolute concentration (by a factor of 7) than present-day stream water. However, the marginal wells have been diluted by groundwater with at least 500 36Cl atoms per 10-6 kg, 30 times richer in 36Cl than present-day stream waters. This spike is most likely due to circulation of precipitation formed during thermonuclear testing to depths of 1,000 m. The amount of 36Cl in the deep fluid at Mokai is 5-10 times less than that predicted from a calculation of the neutron fluxes in the silicic reservoir and underlying greywacke basement rocks. This indicates that the fluids have interacted with more primitive rocks below the drilled depths of the Taupo Volcanic Zone, with the chloride possibly derived from a magmatic brine

  12. Nonsmooth trajectory optimization - An approach using continuous simulated annealing

    Science.gov (United States)

    Lu, Ping; Khan, M. A.

    1993-01-01

    An account is given of the properties of a continuous simulated annealing algorithm that can function as a global optimization tool for nonsmooth dynamic systems, as shown in the case of a trajectory-optimization program implementation. The approach is shown to successfully solve the problem of nonsmooth trajectory optimization for a high performance rigid-body aircraft. The results obtained demonstrate the superiority of the simulated annealing algorithm over widely used algorithms.

  13. Influence of annealing temperature on the magnetic properties of Cr+ implanted AlN thin films

    International Nuclear Information System (INIS)

    Diluted magnetic semiconductor (DMS) AlN:Cr films were produced by implanting various doses Cr+ ions into AlN thin films at room temperature followed by a thermal annealing process. The structural and magnetic characteristics of the samples were investigated as a function of annealing temperature by means of Rutherford backscattering and channeling spectrometry (RBS/C), X-ray diffraction (XRD), Raman spectroscopy, vibrating sample magnetometer (VSM) and SQUID. Structural analyzes demonstrate that implantation damages gradually decrease with the increasing of annealing temperature. Moreover, better recrystallization in the implanted part of the samples was observed for the sample annealed at 950 °C. Both XRD and Raman pattern illustrate that no secondary phase or metal related-peaks were appear in all the samples. Magnetic analysis reveals that annealed Cr+-implanted samples exhibit ferromagnetism at room temperature, however, the sample annealed at 950 °C shows improved magnetic characteristics. The saturation magnetization is estimated to be 9.0×10−5 emu/g and the coercive field (Hc) is approximately 200 Oe for the samples annealed 950 °C. In SQUID analysis, FC/ZFC measurements indicate that the Curie temperature (TC) is well above room temperature

  14. Trapping of self-interstitials in dilute AgCu and AgZn alloys

    International Nuclear Information System (INIS)

    Dilute alloys of AgCu and AgZn have been irradiated at various temperatures within stage II and subsequently annealed up to stage III. It is inferred from the production and the recovery data that mixed dumbbells are formed above stage I which become mobile in the middle of stage II. They are retrapped by the Cu or Zn atoms to form a more stable complex like an impurity-impurity dumbbell

  15. Trapping of self-interstitials in dilute AgCu and AgZn alloys. [Electrons

    Energy Technology Data Exchange (ETDEWEB)

    Maury, F.; Lucasson, A.; Lucasson, P. (Universite Paris 11, 91 - Orsay (France))

    1984-01-01

    Dilute alloys of AgCu and AgZn have been irradiated at various temperatures within stage II and subsequently annealed up to stage III. It is inferred from the production and the recovery data that mixed dumbbells are formed above stage I which become mobile in the middle of stage II. They are retrapped by the Cu or Zn atoms to form a more stable complex like an impurity-impurity dumbbell.

  16. Quantum annealing speedup over simulated annealing on random Ising chains

    Science.gov (United States)

    Zanca, Tommaso; Santoro, Giuseppe E.

    2016-06-01

    We show clear evidence of a quadratic speedup of a quantum annealing (QA) Schrödinger dynamics over a Glauber master equation simulated annealing (SA) for a random Ising model in one dimension, via an equal-footing exact deterministic dynamics of the Jordan-Wigner fermionized problems. This is remarkable, in view of the arguments of H. G. Katzgraber et al. [Phys. Rev. X 4, 021008 (2014), 10.1103/PhysRevX.4.021008], since SA does not encounter any phase transition, while QA does. We also find a second remarkable result: that a "quantum-inspired" imaginary-time Schrödinger QA provides a further exponential speedup, i.e., an asymptotic residual error decreasing as a power law τ-μ of the annealing time τ .

  17. Cryogen-free dilution refrigerators

    International Nuclear Information System (INIS)

    We review briefly our first cryogen-free dilution refrigerator (CF-DR) which was precooled by a GM cryocooler. We then show how today's dry DRs with pulse tube precooling have developed. A few examples of commercial DRs are explained and noteworthy features pointed out. Thereby we describe the general advantages of cryogen-free DRs, but also show where improvements are still desirable. At present, our dry DR has a base temperature of 10 mK and a cooling capacity of 700 μW at a mixing chamber temperature of 100 mK. In our cryostat, in most recent work, an additional refrigeration loop was added to the dilution circuit. This 4He circuit has a lowest temperature of about 1 K and a refrigeration capacity of up to 100 mW at temperatures slightly above 1 K; the dilution circuit and the 4He circuit can be run separately or together. The purpose of this additional loop is to increase the cooling capacity for experiments where the cooling power of the still of the DR is not sufficient to cool cold amplifiers and cables, e.g. in studies on superconducting quantum circuits or astrophysical applications.

  18. 热处理对不同溶剂制备的共混体系太阳电池性能影响%Annealing treatment effects on the performances of solar cells based on different solvent blend systems

    Institute of Scientific and Technical Information of China (English)

    於黄忠; 周晓明; 邓俊裕

    2011-01-01

    The solar cells based on different solvent blends of poly(3-hexylthiophene) (P3HT) and [6,6 ]-phenyl C61-butyric acid methyl ester (PCBM) as acceptors are fabricated. Annealing treatment effects on the performances of solar cells based on different solvent blend systems are analyzed by UV-vis absorption spectroscopy and photoluminescence (PL) spectroscopy. The results show that high boiling point solvent leads to an enhanced P3HT ordering in the P3HT:PCBM blend system, and causes an increased incident light absorption and PL spectrum, which contributes to the enhancement of device performance. After 130 ~C thermal annealing, The UV-Vis absorption, PL spectrum and the performance of the device are further enhanced. The performance of the device prepared with low boiling point chloroform solvent increases obviously after thermal annealing. The solar cell prepared with chlorobenzene solvent after 130 ~C thermal annealing achieves an open circuit voltage(Voo) of O. 57 V, short circuit current density (Iso) of 8.74 mA/cm2 , fill factor (FF) of 59.2% and power conversion efficiency (PCE) of 2.95% under 100 mW/cm2 air-mass 1.5 solar simulator illumination.%本文以poly(3-hexylthiophene)(P3HT)为电子给体材料,[6,6]-phenyl C61-butyric acid methyl ester(PCBM)为电子受体材料,制备出不同溶剂形成的共混体系太阳电池.从薄膜的紫外一可见吸收光谱(uV—vis)、光致发光谱(PL)、原子力表面图形(AFM)等方面,分析了热处理对不同溶剂制备的共混体系太阳电池性能的影响.结果表明较高沸点的溶剂有利于P3HT:PCBM共混体系中P3HT的有序化排列,薄膜的紫外一可见吸收和光致发光增强,太阳电池的能量转

  19. 基于量子退火算法的DPA防御系统优化%The Optimization of DPA Defense System Based on Quantum Annealing Algorithm

    Institute of Scientific and Technical Information of China (English)

    仲明; 贾徽徽; 姜丽莹; 王潮

    2016-01-01

    At present, in ECC side channel attacks and various anti attack measures, the most research is power consumption attack. For attackers, due to the simple power analysis (SPA) referring to the implementation algorithm of cryptographic devices, it makes more dififcult to attack the key. However, differential power analysis (DPA) can recover the correct key via the statistical analysis of multiple power consumption trajectories, and it is less dififcult. Currently, the more use of the counter measures is the power balance. In this paper, we use the quantum annealing algorithm to optimize the anti power consumption attacks based on WDDL and reduce unnecessary additional units. Compared with ExCCel optimization algorithm based on the traditional simulated annealing algorithm, quantum annealing algorithm can obtain the optimal solution with a higher probability. The analysis shows that the method can save the circuit area and power consumption to a large extent, and improves the system’s ability to resist differential power consumption.%在ECC侧信道攻击以及各种抗攻击方法中,目前研究最多的为功耗攻击。一方面,对于攻击者而言,因为简单能量分析(SPA)方法与密码实现算法有较大关联,使其攻击密码的难度较高;另一方面,对于差分功耗分析(DPA),通过多条功率消耗轨迹的分析即可破解得到相应的密钥,难度较低。当前,功耗平衡方法是应用较多的对抗手段。文章利用量子退火算法对基于WDDL的抗功耗攻击方法进行优化,减少不必要的附加单元,相对于基于传统模拟退火算法的ExCCel优化算法,量子退火算法可以以更高的概率更快获得最优解。该方法可在很大程度上节省电路面积和能耗,同时提高系统的抗差分功耗攻击能力。

  20. Thermal Annealing of Exfoliated Graphene

    Directory of Open Access Journals (Sweden)

    Wang Xueshen

    2013-01-01

    Full Text Available Monolayer graphene is obtained by mechanical exfoliation using scotch tapes. The effects of thermal annealing on the tape residues and edges of graphene are researched. Atomic force microscope images showed that almost all the residues could be removed in N2/H2 at 400°C but only agglomerated in vacuum. Raman spectra of the annealed graphene show both the 2D peak and G peak blueshift. The full width at half maximum (FWHM of the 2D peak becomes larger and the intensity ratio of the 2D peak to G peak decreases. The edges of graphene are completely attached to the surface of the substrate after annealing.

  1. Point defect annealing near voids

    International Nuclear Information System (INIS)

    Kinetic calculations were carried out for the annealing of vacancies and interstitials at voids under irradiation conditions. The case in which there is a small energy barrier between a defect and a void (such as might arise from strain effects or solute segregation at void surfaces) has been investigated in detail. With irradiation conditions which yield void swelling, it is found that a small barrier produces a significant bias parameter for preferential annealing. The bias parameter is relatively insensitive to temperature and irradiation rate, but varies with void radius, decreasing as the void size increases

  2. Potential of thermomechanical processing of dilute uranium alloys

    International Nuclear Information System (INIS)

    Preliminary results of studies on uranium-2.25 wt % niobium and uranium-0.75 wt % titanium suggest that thermomechanical processing of dilute uranium alloys might: (1) eliminate the need for quenching to obtain moderate yield strengths (approx. 900 MPa), (2) provide higher usable yield strengths (> 1050 MPa). Analysis of the stress-strain curve of annealed uranium-2.25% niobium indicates that deformation hardening should produce substantial increases in yield strength with very small decreases in ductility. Preliminary rolling experiments reveal that this material can be successfully warm worked over a wide range of conditions. Analysis of the stress-strain curve of solution treated uranium-0.75% titanium indicates that deformation hardening should produce better combinations of yield strength and ductility than can be obtained by age hardening. Preliminary rolliing experiments demonstrate that this alloy can be uniformly hardened at temperatures below 3000C and that the hardening effects of deformation and aging are approximately additive

  3. A miniaturized plastic dilution refrigerator

    International Nuclear Information System (INIS)

    We have built and tested a miniaturized dilution refrigerator, completely contained (still, heat exchanger and mixing chamber) inside a plastic (PVC) tube of 10 mm diameter and 170 mm length. With a 25 cm2 CuNi heat exchanger, it reached temperatures below 50 mK, for circulation rates below 70 μmol/s. The cooling power at 100 mK and 63 μmol/s was 45 μW. The experimental space could accommodate samples up to 6 mm in diameter. (author)

  4. The new SMC dilution refrigerator

    International Nuclear Information System (INIS)

    The dilution refrigerator for the SMC twin solid polarized target at CERN is by far the largest one in operation. The 2.5 liter, 1.5 m long target is loaded horizontally into the cold mixing chamber. A cooling power of 400 mW at 300 mK temperature is available for dynamic nuclear polarization. Proton and deuteron targets are polarized to ±94% and ±47%, respectively. The base temperature of 30 mK enables rotation of the polarization vector without losses. copyright 1995 American Institute of Physics

  5. A New Approach to Determine the Total Airborne N Input into the Soil/Plant System Using 15N Isotope Dilution (ITNI: Results for Agricultural Areas in Central Germany

    Directory of Open Access Journals (Sweden)

    Rolf W.B. Russow

    2001-01-01

    Full Text Available The atmospheric deposition of nitrogen (N in the environment is of great concern due to its impact on natural ecosystems including affecting vegetation, reducing biodiversity, increasing tree growth in forests, and the eutrophication of aquatic systems. Taking into account the average annual N emission into the atmosphere in Germany of about 2 million t N (ammonia/ammonium, NOx, and assuming homogeneous distribution throughout Germany, an average N deposition of 45 kg/ha x year can be calculated. Such high atmospheric N deposition could be confirmed by N balances from long-term field experiments in Central Germany (e.g., the Static Fertilization Experiment in Bad Lauchstädt. By contrast, estimates by standard methods indicate a deposition of only about 30 kg N/ha x year. This is because the standard methods are using wet-only or bulk collectors, which fail to take into account gaseous deposition and the direct uptake of atmospheric N by aerial plant parts. Therefore, a new system was developed using 15N isotope dilution methodology to measure the actual total atmospheric N input into a soil/plant system (Integrated Total Nitrogen Input, ITNI. A soil/plant system is labeled with [15N]ammonium-[15N]nitrate and the total input of airborne N is calculated from the dilution of this tracer by N from the atmosphere. An average annual deposition of 64 ± 11 kg/ha x year from 1994–2000 was measured with the ITNI system at the Bad Lauchst?dt research farm in the dry belt of Central Germany. Measurements in 1999/2000 at three other sites in Central Germany produced deposition rates of about 60 kg/ha x year. These data clearly show that the total atmospheric N deposition into the soil/plant system determined by the newly developed ITNI system significantly exceeds that obtained from standard wet-only and bulk collectors. The higher atmospheric N depositions found closely match those postulated from the N balances of long-term agricultural field

  6. An Introduction to Simulated Annealing

    Science.gov (United States)

    Albright, Brian

    2007-01-01

    An attempt to model the physical process of annealing lead to the development of a type of combinatorial optimization algorithm that takes on the problem of getting trapped in a local minimum. The author presents a Microsoft Excel spreadsheet that illustrates how this works.

  7. Annealing properties of rice starch.

    Science.gov (United States)

    Thermal properties of starch can be modified by annealing, i.e., a pre-treatment in excessive amounts of water at temperatures below the gelatinization temperatures. This treatment is known to improve the crystalline properties, and is a useful tool to gain a better control of the functional proper...

  8. Non-conventional Superconductors and diluted Ising Model

    CERN Document Server

    Ni, Xuan Zhong

    2016-01-01

    This paper demonstrates that the results of a Monte Carlo simulation of a diluted 2D Ising antiferromagnetic system corresponds with the phase diagram for non conventional superconductors. An energy gap of this system is defined. We also find a strange phenomenon that when the lattice size of simulation increased the crystal structure becomes more like quasi crystal at the low temperature.

  9. Metriplectic Simulated Annealing

    Science.gov (United States)

    Morrison, P. J.; Flierl, G. R.

    2015-11-01

    Metriplectic dynamics is a general form for dynamical systems that represent the first and second laws of thermodynamics, energy conservation and entropy production. Entropy production provides asymptotic stability to equilibrium states, which because of constraints need not be trivial. The formalism will be used to perform quasigeostrophic computations, akin to those of, for obtaining a variety of vortex states.

  10. Computer registration of radioactive indicator-dilution curves.

    Science.gov (United States)

    Shepherd, A P; Perry, M A; Alexander, G M; Granger, D N; Riedel, G L; Kvietys, P R; Franke, C P

    1983-12-01

    A system is described for recording indicator-dilution curves produced by gamma radiation-emitting tracers. The system consists of a flow-through cuvette in a well counter, appropriate commercially available gamma radiation-detecting equipment, an Apple II computer, and a two-channel pulse-counting interface of our own design. With the counting interface and the software described here, an investigator can simultaneously record two indicator-dilution curves produced by gamma emitters. Instead of having to wait hours or days for results, the investigator can watch the data being recorded and display the results in graphic form almost immediately after each injection. PMID:6660306

  11. Dilute Potts model in two dimensions

    Science.gov (United States)

    Qian, Xiaofeng; Deng, Youjin; Blöte, Henk W. J.

    2005-11-01

    We study the two-dimensional dilute q -state Potts model by means of transfer-matrix and Monte Carlo methods. Using the random-cluster representation, we include noninteger values of q . We locate phase transitions in the three-dimensional parameter space of q , the Potts coupling K⩾0 , and the chemical potential of the vacancies. The critical plane is found to contain a line of fixed points that divides into a critical branch and a tricritical one, just as predicted by the renormalization scenario formulated by Nienhuis for the dilute Potts model. The universal properties along the line of fixed points agree with the theoretical predictions. We also determine the density of the vacancies along these branches. For q=2-2 we obtain the phase diagram in a three-dimensional parameter space that also includes a coupling V⩾0 between the vacancies. For q=2 , the latter space contains the Blume-Capel model as a special case. We include a determination of the tricritical point of this model, as well as an analysis of percolation clusters constructed on tricritical Potts configurations for noninteger q . This percolation study is based on Monte Carlo algorithms that include local updates flipping between Potts sites and vacancies. The bond updates are performed locally for q1 . The updates for q>1 use a number of operations per site independent of the system size.

  12. Annealing relaxation of ultrasmall gold nanostructures

    Science.gov (United States)

    Chaban, Vitaly

    2015-01-01

    Except serving as an excellent gift on proper occasions, gold finds applications in life sciences, particularly in diagnostics and therapeutics. These applications were made possible by gold nanoparticles, which differ drastically from macroscopic gold. Versatile surface chemistry of gold nanoparticles allows coating with small molecules, polymers, biological recognition molecules. Theoretical investigation of nanoscale gold is not trivial, because of numerous metastable states in these systems. Unlike elsewhere, this work obtains equilibrium structures using annealing simulations within the recently introduced PM7-MD method. Geometries of the ultrasmall gold nanostructures with chalcogen coverage are described at finite temperature, for the first time.

  13. Hybrid Quantum Annealing for Clustering Problems

    OpenAIRE

    Tanaka, Shu; Tamura, Ryo; Sato, Issei; Kurihara, Kenichi

    2011-01-01

    We develop a hybrid type of quantum annealing in which we control temperature and quantum field simultaneously. We study the efficiency of proposed quantum annealing and find a good schedule of changing thermal fluctuation and quantum fluctuation. In this paper, we focus on clustering problems which are important topics in information science and engineering. We obtain the better solution of the clustering problem than the standard simulated annealing by proposed quantum annealing.

  14. Quantum annealing: An introduction and new developments

    OpenAIRE

    Ohzeki, Masayuki; Nishimori, Hidetoshi

    2010-01-01

    Quantum annealing is a generic algorithm using quantum-mechanical fluctuations to search for the solution of an optimization problem. The present paper first reviews the fundamentals of quantum annealing and then reports on preliminary results for an alternative method. The review part includes the relationship of quantum annealing with classical simulated annealing. We next propose a novel quantum algorithm which might be available for hard optimization problems by using a classical-quantum ...

  15. Quantum Annealing for Variational Bayes Inference

    OpenAIRE

    Sato, Issei; Kurihara, Kenichi; Tanaka, Shu; Nakagawa, Hiroshi; Miyashita, Seiji

    2014-01-01

    This paper presents studies on a deterministic annealing algorithm based on quantum annealing for variational Bayes (QAVB) inference, which can be seen as an extension of the simulated annealing for variational Bayes (SAVB) inference. QAVB is as easy as SAVB to implement. Experiments revealed QAVB finds a better local optimum than SAVB in terms of the variational free energy in latent Dirichlet allocation (LDA).

  16. Theory of radiation disordering and annealing semiconductors

    International Nuclear Information System (INIS)

    A new model of radiation disordering semiconductors is proposed. According to this model disordering clusters capable to the self-annealing are stabilized by autolocalized electronic excitations (electrons, holes, excitons). Impulse annealing this medium takes place if the electron stoppers are annihilated and so the disordered clusters are resolved. This model is in accordance with experimental data of amorphization and impulse annealing. (author)

  17. Characterization of the Dilute Ising Antiferromagnet

    Energy Technology Data Exchange (ETDEWEB)

    Wiener, T.

    2000-09-12

    A spin glass is a magnetic ground state in which ferromagnetic and antiferromagnetic exchange interactions compete, thereby creating frustration and a multidegenerate state with no long range order. An Ising system is a system where the spins are constrained to lie parallel or antiparallel to a primary axis. There has been much theoretical interest in the past ten years in the effects of applying a magnetic field transverse to the primary axis in an Ising spin glass at low temperatures and thus study phase transitions at the T=0 limit. The focus of this study is to search for and characterize a new Ising spin glass system. This is accomplished by site diluting yttrium for terbium in the crystalline material TbNi{sub 2}Ge{sub 2}. The first part of this work gives a brief overview of the physics of rare earth magnetism and an overview of experimental characteristics of spin glasses. This is followed by the methodology used to manufacture the large single crystals used in this study, as well as the measurement techniques used. Next, a summary of the results of magnetic measurements on across the dilution series from pure terbium to pure yttrium is presented. This is followed by detailed measurements on particular dilutions which demonstrate spin glass behavior. Pure TbNi{sub 2}Ge{sub 2} is an Ising antiferromagnet with a several distinct metamagnetic states below 17 K. As the terbium is alloyed with yttrium, these magnetic states are weakened in a consistent manner, as is seen in measurements of the transition temperatures and analysis of Curie-Weiss behavior at high temperature. At low concentrations of terbium, below 35%, long range order is no longer present and a spin-glass-like state emerges. This state is studied through various measurements, dc and ac susceptibility, resistivity, and specific heat. This magnetic behavior was then compared to that of other well characterized spin glasses. It is concluded that there is a region of concentration s for which a spin

  18. A compact rotating dilution refrigerator

    CERN Document Server

    Fear, M J; Chorlton, D A; Zmeev, D E; Gillott, S J; Sellers, M C; Richardson, P P; Agrawal, H; Batey, G; Golov, A I

    2013-01-01

    We describe the design and performance of a new rotating dilution refrigerator that will primarily be used for investigating the dynamics of quantized vortices in superfluid 4He. All equipment required to operate the refrigerator and perform experimental measurements is mounted on two synchronously driven, but mechanically decoupled, rotating carousels. The design allows for relative simplicity of operation and maintenance and occupies a minimal amount of space in the laboratory. Only two connections between the laboratory and rotating frames are required for the transmission of electrical power and helium gas recovery. Measurements on the stability of rotation show that rotation is smooth to around 0.001 rad/s up to angular velocities in excess of 2.5 rad/s. The behavior of a high-Q mechanical resonator during rapid changes in rotation has also been investigated.

  19. A compact rotating dilution refrigerator.

    Science.gov (United States)

    Fear, M J; Walmsley, P M; Chorlton, D A; Zmeev, D E; Gillott, S J; Sellers, M C; Richardson, P P; Agrawal, H; Batey, G; Golov, A I

    2013-10-01

    We describe the design and performance of a new rotating dilution refrigerator that will primarily be used for investigating the dynamics of quantized vortices in superfluid (4)He. All equipment required to operate the refrigerator and perform experimental measurements is mounted on two synchronously driven, but mechanically decoupled, rotating carousels. The design allows for relative simplicity of operation and maintenance and occupies a minimal amount of space in the laboratory. Only two connections between the laboratory and rotating frames are required for the transmission of electrical power and helium gas recovery. Measurements on the stability of rotation show that rotation is smooth to around 10(-3) rad s(-1) up to angular velocities in excess of 2.5 rad s(-1). The behavior of a high-Q mechanical resonator during rapid changes in rotation has also been investigated. PMID:24182127

  20. Estimating DNAPL composition and VOC dilution from extraction well data

    International Nuclear Information System (INIS)

    Field data from a large-scale ground-water extraction system at the Savannah River Site in South Carolina indicate that considerable dilution of volatile organic compounds (VOCs) occurs at extraction wells when compared with the effective solubilities of the VOC components (TCE and PCE) in the dense, nonaqueous phase liquid (DNAPL) source zone. This dilution is believed to be due to the convergence of both contaminated and uncontaminated streamtubes on the extraction wells studied. Thus, the measured concentrations of dissolved VOCs in extraction wells appear to be principally functions of (1) the effective solubilities of the DNAPL components, and (2) the dilution due to streamtube convergence on the extraction wells. A simple method for computing DNAPL composition and the dilution factor from extraction well data is presented for the case when dilution is the dominant mechanism that causes the measured ground-water concentrations of dissolved VOC components to be significantly less than their respective effect solubilities relative to the DNAPL mixture. This method successfully computes the molar composition of a PCE/TCE DNAPL, bailed from a pair of monitor wells at the Savannah River Site, using the measured concentrations of PCE and TCE in ground waters from the same pair of wells. The method is then used to predict the variation of DNAPL composition within the aquifer from VOC data sampled at all 11 extraction wells. Such information is of considerable use in choosing solvent-specific surfactants for enhanced remediation operations

  1. Analysis of Trivium by a Simulated Annealing variant

    DEFF Research Database (Denmark)

    Borghoff, Julia; Knudsen, Lars Ramkilde; Matusiewicz, Krystian

    2010-01-01

    characteristic of equation systems that may be efficiently solvable by the means of such algorithms is provided. As an example, we investigate equation systems induced by the problem of recovering the internal state of the stream cipher Trivium. We propose an improved variant of the simulated annealing method...

  2. Feasibility of Simulated Annealing Tomography

    CERN Document Server

    Vo, Nghia T; Moser, Herbert O

    2014-01-01

    Simulated annealing tomography (SAT) is a simple iterative image reconstruction technique which can yield a superior reconstruction compared with filtered back-projection (FBP). However, the very high computational cost of iteratively calculating discrete Radon transform (DRT) has limited the feasibility of this technique. In this paper, we propose an approach based on the pre-calculated intersection lengths array (PILA) which helps to remove the step of computing DRT in the simulated annealing procedure and speed up SAT by over 300 times. The enhancement of convergence speed of the reconstruction process using the best of multiple-estimate (BoME) strategy is introduced. The performance of SAT under different conditions and in comparison with other methods is demonstrated by numerical experiments.

  3. Recursive simulation of quantum annealing

    CERN Document Server

    Sowa, A P; Samson, J H; Savel'ev, S E; Zagoskin, A M; Heidel, S; Zúñiga-Anaya, J C

    2015-01-01

    The evaluation of the performance of adiabatic annealers is hindered by lack of efficient algorithms for simulating their behaviour. We exploit the analyticity of the standard model for the adiabatic quantum process to develop an efficient recursive method for its numerical simulation in case of both unitary and non-unitary evolution. Numerical simulations show distinctly different distributions for the most important figure of merit of adiabatic quantum computing --- the success probability --- in these two cases.

  4. Recursive simulation of quantum annealing

    International Nuclear Information System (INIS)

    The evaluation of the performance of adiabatic annealers is hindered by the lack of efficient algorithms for simulating their behaviour. We exploit the analyticity of the standard model for the adiabatic quantum process to develop an efficient recursive method for its numerical simulation in case of both unitary and non-unitary evolution. Numerical simulations show distinctly different distributions for the most important figure of merit of adiabatic quantum computing—the success probability—in these two cases. (paper)

  5. Computational algorithm for molybdenite concentrate annealing

    International Nuclear Information System (INIS)

    Computational algorithm is presented for annealing of molybdenite concentrate with granulated return dust and that of granulated molybdenite concentrate. The algorithm differs from the known analogies for sulphide raw material annealing by including the calculation of return dust mass in stationary annealing; the latter quantity varies form the return dust mass value obtained in the first iteration step. Masses of solid products are determined by distribution of concentrate annealing products, including return dust and benthonite. The algorithm is applied to computations for annealing of other sulphide materials. 3 refs

  6. Very Fast Simulated Re-Annealing

    OpenAIRE

    Ingber, Lester

    1989-01-01

    Draft An algorithm is developed to statistically find the best global fit of a nonlinear non-convex cost-function over a D-dimensional space. It is argued that this algorithm permits an annealing schedule for ‘‘temperature’’ T decreasing exponentially in annealing-time k, T = T0 exp(−ck1/D). The introduction of re-annealing also permits adaptation to changing sensitivities in the multidimensional parameter-space. This annealing schedule is faster than fast Cauchy annealing, ...

  7. Production and distribution of dilute species in semiconducting materials

    Energy Technology Data Exchange (ETDEWEB)

    James, Ralph B.; Camarda, Giuseppe; Bolotnikov, Aleksey E.; Hossain, Anwar; Yang, Ge; Kim, Kihyun

    2016-09-06

    Technologies are described effective to implement systems and methods of producing a material. The methods comprise receiving a tertiary semiconductor sample with a dilute species. The sample has two ends. The first end of the sample includes a first concentration of the dilute species lower than a second concentration of the dilute species in the second end of the sample. The method further comprises heating the sample in a chamber. The chamber has a first zone and a second zone. The first zone having a first temperature higher than a second temperature in the second zone. The sample is orientated such that the first end is in the first zone and the second end is in the second zone.

  8. Application of Cryocoolers to a Vintage Dilution Refrigerator

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Richard; Smith, Gary; Ruschman, Mark; /Fermilab; Beaty, Jim; /Minnesota U.

    2011-06-06

    A dilution refrigerator is required for 50mK detector operation of CDMS (Cryogenic Dark Matter Search). Besides shielding the dilution refrigerator itself, the liquid nitrogen shield and liquid helium bath in the refrigerator cool the detector cryostat heat shields and cool electronics, resulting in significant external heat loads at 80K and at 4K. An Oxford Instruments Kelvinox 400 has served this role for ten years but required daily transfers of liquid nitrogen and liquid helium. Complicating the cryogen supply is the location 800 meters below ground in an RF shielded, class 10000 clean room at Soudan, MN. Nitrogen and helium re-liquefiers using cryocoolers were installed outside the clean room and continuously condense room temperature gas and return the liquids to the dilution refrigerator through a transfer line. This paper will describe the design, installation, controls and performance of liquefaction systems.

  9. Thermal diffusion in dilute nanofluids investigated by photothermal interferometry

    Science.gov (United States)

    Philip, J.; Nisha, M. R.

    2010-03-01

    We have carried out a theoretical analysis of the dependence of the particle mass fraction on the thermal diffusivity of dilute suspensions of nanoparticles in liquids (dilute nanofluids). The analysis takes in to account adsorption of an ordered layer of solvent molecules around the nanoparticles. It is found that thermal diffusivity decreases with mass fraction for sufficiently small particle sizes. Beyond a critical particle size thermal diffusivity begins to increase with mass fraction for the same system. The results have been verified experimentally by measuring the thermal diffusivity of dilute suspensions of TiO2 nanoparticles dispersed in polyvinyl alcohol (PVA) medium. The effect is attributed to Kapitza resistance of thermal waves in the medium.

  10. Thermal diffusion in dilute nanofluids investigated by photothermal interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Philip, J; Nisha, M R, E-mail: jp@cusat.ac.i [Department of Instrumentation and STIC, Cochin University of Science and Technology, Cochin 682 022 (India)

    2010-03-01

    We have carried out a theoretical analysis of the dependence of the particle mass fraction on the thermal diffusivity of dilute suspensions of nanoparticles in liquids (dilute nanofluids). The analysis takes in to account adsorption of an ordered layer of solvent molecules around the nanoparticles. It is found that thermal diffusivity decreases with mass fraction for sufficiently small particle sizes. Beyond a critical particle size thermal diffusivity begins to increase with mass fraction for the same system. The results have been verified experimentally by measuring the thermal diffusivity of dilute suspensions of TiO{sub 2} nanoparticles dispersed in polyvinyl alcohol (PVA) medium. The effect is attributed to Kapitza resistance of thermal waves in the medium.

  11. Annealing of ion implanted silicon

    International Nuclear Information System (INIS)

    The newer uses of ion implantation require a higher dose rate. This has led to the introduction of high beam current implanters; the wafers move in front of a stationary beam to give a scanning effect. This can lead to non-uniform heating of the wafer. Variations in the sheet resistance of the layers can be very non-uniform following thermal annealing. Non-uniformity in the effective doping both over a single wafer and from one wafer to another, can affect the usefulness of ion implantation in high dose rate applications. Experiments to determine the extent of non-uniformity in sheet resistance, and to see if it is correlated to the annealing scheme have been carried out. Details of the implantation parameters are given. It was found that best results were obtained when layers were annealed at the maximum possible temperature. For arsenic, phosphorus and antimony layers, improvements were observed up to 12000C and boron up to 9500C. Usually, it is best to heat the layer directly to the maximum temperature to produce the most uniform layer; with phosphorus layers however it is better to pre-heat to 10500C. (U.K.)

  12. Quantum Annealing for Constrained Optimization

    Science.gov (United States)

    Hen, Itay; Spedalieri, Federico M.

    2016-03-01

    Recent advances in quantum technology have led to the development and manufacturing of experimental programmable quantum annealers that promise to solve certain combinatorial optimization problems of practical relevance faster than their classical analogues. The applicability of such devices for many theoretical and real-world optimization problems, which are often constrained, is severely limited by the sparse, rigid layout of the devices' quantum bits. Traditionally, constraints are addressed by the addition of penalty terms to the Hamiltonian of the problem, which, in turn, requires prohibitively increasing physical resources while also restricting the dynamical range of the interactions. Here, we propose a method for encoding constrained optimization problems on quantum annealers that eliminates the need for penalty terms and thereby reduces the number of required couplers and removes the need for minor embedding, greatly reducing the number of required physical qubits. We argue the advantages of the proposed technique and illustrate its effectiveness. We conclude by discussing the experimental feasibility of the suggested method as well as its potential to appreciably reduce the resource requirements for implementing optimization problems on quantum annealers and its significance in the field of quantum computing.

  13. Negative magnetophoresis in diluted ferrofluid flow.

    Science.gov (United States)

    Hejazian, Majid; Nguyen, Nam-Trung

    2015-07-21

    We report magnetic manipulation of non-magnetic particles suspended in diluted ferrofluid. Diamagnetic particles were introduced into a circular chamber to study the extent of their deflection under the effect of a non-uniform magnetic field of a permanent magnet. Since ferrofluid is a paramagnetic medium, it also experiences a bulk magnetic force that in turn induces a secondary flow opposing the main hydrodynamic flow. Sheath flow rate, particle size, and magnetic field strength were varied to examine this complex behaviour. The combined effect of negative magnetophoresis and magnetically induced secondary flow leads to various operation regimes, which can potentially find applications in separation, trapping and mixing of diamagnetic particles such as cells in a microfluidic system. PMID:26054840

  14. Disorder Problem In Diluted Magnetic Semiconductors

    Science.gov (United States)

    Nelson, Ryky; Ekuma, Chinedu; Terletska, Hanna; Sudhindra, Vidhyadhiraja; Moreno, Juana; Jarrell, Mark

    2015-03-01

    Motivated by experimental studies addressing the role of impurity disorder in diluted magnetic semiconductors (DMS), we investigate the effects of disorder using a simple tight-binding Hamiltonian with random impurity potential and spin-fermion exchange which is self-consistently solved using the typical medium theory. Adopting the typical density of states (TDoS) as the order parameter, we find that the TDoS vanishes below a critical concentration of the impurity, which indicates an Anderson localization transition in the system. Our results qualitatively explain why at concentrations lower than a critical value DMS are insulating and paramagnetic, while at larger concentrations are ferromagnetic. We also compare several simple models to explore the interplay between ferromagnetic order and disorder induced insulating behavior, and the role of the spin-orbit interaction on this competition. We apply our findings to (Ga,Mn)As and (Ga,Mn)N to compare and contrast their phase diagrams.

  15. Rapid thermal annealing and crystallization mechanisms study of silicon nanocrystal in silicon carbide matrix

    Directory of Open Access Journals (Sweden)

    Wan Zhenyu

    2011-01-01

    Full Text Available Abstract In this paper, a positive effect of rapid thermal annealing (RTA technique has been researched and compared with conventional furnace annealing for Si nanocrystalline in silicon carbide (SiC matrix system. Amorphous Si-rich SiC layer has been deposited by co-sputtering in different Si concentrations (50 to approximately 80 v%. Si nanocrystals (Si-NC containing different grain sizes have been fabricated within the SiC matrix under two different annealing conditions: furnace annealing and RTA both at 1,100°C. HRTEM image clearly reveals both Si and SiC-NC formed in the films. Much better "degree of crystallization" of Si-NC can be achieved in RTA than furnace annealing from the research of GIXRD and Raman analysis, especially in high-Si-concentration situation. Differences from the two annealing procedures and the crystallization mechanism have been discussed based on the experimental results.

  16. Rapid thermal annealing and crystallization mechanisms study of silicon nanocrystal in silicon carbide matrix.

    Science.gov (United States)

    Wan, Zhenyu; Huang, Shujuan; Green, Martin A; Conibeer, Gavin

    2011-01-01

    In this paper, a positive effect of rapid thermal annealing (RTA) technique has been researched and compared with conventional furnace annealing for Si nanocrystalline in silicon carbide (SiC) matrix system. Amorphous Si-rich SiC layer has been deposited by co-sputtering in different Si concentrations (50 to approximately 80 v%). Si nanocrystals (Si-NC) containing different grain sizes have been fabricated within the SiC matrix under two different annealing conditions: furnace annealing and RTA both at 1,100°C. HRTEM image clearly reveals both Si and SiC-NC formed in the films. Much better "degree of crystallization" of Si-NC can be achieved in RTA than furnace annealing from the research of GIXRD and Raman analysis, especially in high-Si-concentration situation. Differences from the two annealing procedures and the crystallization mechanism have been discussed based on the experimental results. PMID:21711625

  17. Effects of Bio-sludge Concentration and Dilution Rate on the Efficiency of Sequencing Batch Reactor (SBR) System for Textile Wastewater Treatment

    OpenAIRE

    Suntud Sirianuntapiboon; Sarun Maneewon

    2012-01-01

    The color removal efficiency of a sequencing batch reactor (SBR) system with synthetic textile wastewater (STWW) containing 80 mg/L disperse dye increased with the increase of mixed liquor suspended solids (MLSS) or solids retention time (SRT). The color removal efficiency was over 98% at an MLSS of 4,000 mg/L and SRT of over 25 days. Also, the color removal efficiency decreased with the increase of dye concentration. Both disperse blue 60 and disperse red 60 repressed the growths and activit...

  18. Exactly soluble diluted random one-dimensional lattices

    NARCIS (Netherlands)

    Nieuwenhuizen, Th.M.

    1984-01-01

    Exact solutions for the characteristic function, which determines the density of states and inverse localization length, and one-particle Green function are presented for a class of lattice models with diluted randomness. (Examples are: harmonic, electronic, relaxation and X-Y spin systems.) With pr

  19. Annealing study of poly(etheretherketone)

    Science.gov (United States)

    Cebe, Peggy

    1988-01-01

    Annealing of PEEK has been studied for two materials cold-crystallized from the rubbery amorphous state. The first material is a low molecular weight PEEK; the second is commercially available neat resin. Differential scanning calorimetry was used to monitor the melting behavior of annealed samples. The effect of thermal history on melting behavior is very complex and depends upon annealing temperature, residence time at the annealing temperature, and subsequent scanning rate. Thermal stability of both materials is improved by annealing, and for an annealing temperature near the melting point, the polymer can be stabilized against reorganization during the scan. Variations of density, degree of crystallinity, and X-ray long period were studied as a function of annealing temperature for the commercial material.

  20. Recursive Branching Simulated Annealing Algorithm

    Science.gov (United States)

    Bolcar, Matthew; Smith, J. Scott; Aronstein, David

    2012-01-01

    This innovation is a variation of a simulated-annealing optimization algorithm that uses a recursive-branching structure to parallelize the search of a parameter space for the globally optimal solution to an objective. The algorithm has been demonstrated to be more effective at searching a parameter space than traditional simulated-annealing methods for a particular problem of interest, and it can readily be applied to a wide variety of optimization problems, including those with a parameter space having both discrete-value parameters (combinatorial) and continuous-variable parameters. It can take the place of a conventional simulated- annealing, Monte-Carlo, or random- walk algorithm. In a conventional simulated-annealing (SA) algorithm, a starting configuration is randomly selected within the parameter space. The algorithm randomly selects another configuration from the parameter space and evaluates the objective function for that configuration. If the objective function value is better than the previous value, the new configuration is adopted as the new point of interest in the parameter space. If the objective function value is worse than the previous value, the new configuration may be adopted, with a probability determined by a temperature parameter, used in analogy to annealing in metals. As the optimization continues, the region of the parameter space from which new configurations can be selected shrinks, and in conjunction with lowering the annealing temperature (and thus lowering the probability for adopting configurations in parameter space with worse objective functions), the algorithm can converge on the globally optimal configuration. The Recursive Branching Simulated Annealing (RBSA) algorithm shares some features with the SA algorithm, notably including the basic principles that a starting configuration is randomly selected from within the parameter space, the algorithm tests other configurations with the goal of finding the globally optimal

  1. Simulated Annealing Clustering for Optimum GPS Satellite Selection

    Directory of Open Access Journals (Sweden)

    M. Ranjbar

    2012-05-01

    Full Text Available This paper utilizes a clustering approach based on Simulated Annealing (SA method to select optimum satellite subsets from the visible satellites. Geometric Dilution of Precision (GDOP is used as criteria of optimality. The lower the values of the GDOP number, the better the geometric strength, and vice versa. Not needing to calculate the inverse matrix, which is time-consuming process, is a dramatically important advantage of using this method, so a great reduction in computational cost is achieved. SA is a powerful technique to obtain a close approximation to the global optimum for a given problem. The evaluation of the performance of the proposed method is done by validation measures. The external validation measures, entropy and purity, are used to measure the extent to which cluster labels affirm with the externally given class labels. The overall purity and entropy is 0.9015 and 0.3993, respectively which is an excellent result.

  2. Numerical diffusion and the tracking of solute fields in system codes. Part III. Application to a boron dilution transient analysis in the AP600

    International Nuclear Information System (INIS)

    For pt.II see ibid., vol.179, p.321-44, 1998. A study of a pump restart scenario in the AP600 with an unborated coolant plug in two of the four cold legs is presented. It has been performed with TRAC-PF1/MOD2 coupled with a 3-dimensional core neutronics model based on the nodal expansion method (NEM), and high order boron tracking algorithms. These are based on ULTIMATE-QUICKEST for 1-dimensional components and a flux corrected method developed by Smolarckievicz in the 3-dimensional vessel in order to reduce the numerical diffusion inherent to the upwind method used by most system codes to solve the transport equations. No turbulent diffusion model was included in the calculation to produce more conservative results. The results show that reduction of the numerical diffusion yields predictions with a significantly reduced margin in the size of the unborated plugs allowed to form in the primary side piping. In addition, two pump restart strategies have been suggested by the results, which could substantially decrease the size of an unborated plug injected into the core, in case it was suspected to have formed in a primary loop. (orig.)

  3. Cost effectiveness of dilute chemical decontamination

    International Nuclear Information System (INIS)

    The basic principles of dilute chemical decontamination are described, as well as the method of application. Methods of computing savings in radiation dose and costs are presented, with results from actual experience and illustrative examples. It is concluded that dilute chemical decontamination is beneficial in many cases. It reduces radiation exposure of workers, saves money, and simplifies maintenance work

  4. Comparison of short time annealing of implanted silicon layers with tungsten-halogen lamp and mercury arc lamp sources

    International Nuclear Information System (INIS)

    Short time anneal (STA) experiments were performed in a specially designed system which uses either a bank of Tungsten-Halogen lamps or a moving Mercury arc lamp as the light source. Both STA results were compared with conventional furnace anneal. The Mercury arc lamp anneal is found to be a critical process but optimization for wafer damage free conditions can be achieved. The anneals result in general in a better profile control which is most outspoken for shallow Boron implants while the electrical activation is comparable for all elements to that obtained with Tungsten-Halogen or furnace anneal

  5. An autonomous dilution micro refrigerator

    International Nuclear Information System (INIS)

    In the dilution refrigerator3He circulates due to its condensation in a vessel with the temperature of 0.35-0.4K. The latter is cooled by the pumping of 3He from another bath by means of a sorption pump. A temperature 12 hours. The sample holder is placed in an upper part of the refrigerator and is connected with a mixer by a copper heat conductor. They are surrounded by screens at temperatures 0.4, 4.2 and ∼100K. The low temperature part is tied to the 0.4 K screen and centered by a polymer threads. A heat flux from the 0.4 K screen to the mixer is less than 0.1 μW. Inner volumes are filled with 0.2 mol of 4He, 0.1 mol of 3He and 0.05 mol of a mixture 40%3He+60%4He respectively. These gases remain all time inside the apparatus. The refrigerator is working when inserted in a 35 l transport cryostat with a liquid helium and operate during 5-6 days. The refrigerator is designed to cool down low temperature detectors or samples in experiments that do not require a high refrigerating capacity.

  6. An autonomous dilution micro refrigerator

    Energy Technology Data Exchange (ETDEWEB)

    Edelman, V S [P. L. Kapitza Institute for Physical Problems, Russian Academy of Sciences, ul. Kosygina 2, Moscow 117334 (Russian Federation)], E-mail: edelman@kapitza.ras.ru

    2009-02-01

    In the dilution refrigerator{sup 3}He circulates due to its condensation in a vessel with the temperature of 0.35-0.4K. The latter is cooled by the pumping of {sup 3}He from another bath by means of a sorption pump. A temperature <0.1 K is maintained for >12 hours. The sample holder is placed in an upper part of the refrigerator and is connected with a mixer by a copper heat conductor. They are surrounded by screens at temperatures 0.4, 4.2 and {approx}100K. The low temperature part is tied to the 0.4 K screen and centered by a polymer threads. A heat flux from the 0.4 K screen to the mixer is less than 0.1 {mu}W. Inner volumes are filled with 0.2 mol of {sup 4}He, 0.1 mol of {sup 3}He and 0.05 mol of a mixture 40%{sup 3}He+60%{sup 4}He respectively. These gases remain all time inside the apparatus. The refrigerator is working when inserted in a 35 l transport cryostat with a liquid helium and operate during 5-6 days. The refrigerator is designed to cool down low temperature detectors or samples in experiments that do not require a high refrigerating capacity.

  7. Turbulence of Dilute Polymer Solution

    CERN Document Server

    Xi, Heng-Dong; Xu, Haitao

    2013-01-01

    In fully developed three dimensional fluid turbulence the fluctuating energy is supplied at large scales, cascades through intermediate scales, and dissipates at small scales. It is the hallmark of turbulence that for intermediate scales, in the so called inertial range, the average energy flux is constant and independent of viscosity [1-3]. One very important question is how this range is altered, when an additional agent that can also transport energy is added to the fluid. Long-chain polymers dissolved at very small concentrations in the fluid are such an agent [4,5]. Based on prior work by de Gennes and Tabor [6,7] we introduce a theory that balances the energy flux through the turbulent cascade with that of the energy flux into the elastic degrees of freedom of the dilute long-chain polymer solution. We propose a refined elastic length scale, $r_\\varepsilon$, which describes the effect of polymer elasticity on the turbulence energy cascade. Our experimental results agree excellently with this new energy ...

  8. Dilute Oxygen Combustion - Phase 3 Report

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Michael F.

    2000-05-31

    Dilute Oxygen Combustion (DOC) burners have been successfully installed and operated in the reheat furnace at Auburn Steel Co., Inc., Auburn, NY, under Phase 3 of the Dilute Oxygen Combustion project. Two new preheat zones were created employing a total of eight 6.5 MMBtu/hr capacity burners. The preheat zones provide a 30 percent increase in maximum furnace production rate, from 75 tph to 100 tph. The fuel rate is essentially unchanged, with the fuel savings expected from oxy-fuel combustion being offset by higher flue gas temperatures. When allowance is made for the high nitrogen level and high gas phase temperature in the furnace, measured NOx emissions are in line with laboratory data on DOC burners developed in Phase 1 of the project. Burner performance has been good, and there have been no operating or maintenance problems. The DOC system continues to be used as part of Auburn Steel's standard reheat furnace practice. High gas phase temperature is a result of the high firing density needed to achieve high production rates, and little opportunity exists for improvement in that area. However, fuel and NOx performance can be improved by further conversion on furnace zones to DOC burners, which will lower furnace nitrogen levels. Major obstacles are cost and concern about increased formation of oxide scale on the steel. Oxide scale formation may be enhanced by exposure of the steel to higher concentrations of oxidizing gas components (primarily products of combustion) in the higher temperature zones of the furnace. Phase 4 of the DOC project will examine the rate of oxide scale formation in these higher temperature zones and develop countermeasures that will allow DOC burners to be used successfully in these furnace zones.

  9. Dilute Oxygen Combustion Phase 3 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Riley, M.F.; Ryan, H.M.

    2000-05-31

    Dilute Oxygen Combustion (DOC) burners have been successfully installed and operated in the reheat furnace at Auburn Steel Co., Inc., Auburn, NY, under Phase 3 of the Dilute Oxygen Combustion project. Two new preheat zones were created employing a total of eight 6.5 MMBtu/hr capacity burners. The preheat zones provide a 30 percent increase in maximum furnace production rate, from 75 tph to 100 tph. The fuel rate is essentially unchanged, with the fuel savings expected from oxy-fuel combustion being offset by higher flue gas temperatures. When allowance is made for the high nitrogen level and high gas phase temperature in the furnace, measured NOx emissions are in line with laboratory data on DOC burners developed in Phase 1 of the project. Burner performance has been good and there have been no operating or maintenance problems. The DOC system continues to be used as part of Auburn Steel?s standard reheat furnace practice. High gas phase temperature is a result of the high firing density needed to achieve high production rates, and little opportunity exists for improvement in that area. However, fuel and NOx performance can be improved by further conversion of furnace zones to DOC burners, which will lower furnace nitrogen levels. Major obstacles are cost and concern about increased formation of oxide scale on the steel. Oxide scale formation may be enhanced by exposure of the steel to higher concentrations of oxidizing gas components (primarily products of combustion) in the higher temperature zones of the furnace. Phase 4 of the DOC project will examine the rate of oxide scale formation in these higher temperature zones and develop countermeasures that will allow DOC burners to be used successfully in these furnace zones.

  10. Thermal annealing, irradiation, and stress in multilayers

    International Nuclear Information System (INIS)

    The evolution of the microstructure of a TiN/B-C-N multilayered thin film during thermal annealing and irradiation has been studied by low angle X-ray diffraction and transmission electron microscopy. Stress has been determined by curvature measurements. After deposition, TiN is crystalline while B-C-N is amorphous. Thermal anneals in vacuum at 600-1000 deg. C lead to an increase of the bilayer repeat length and to a phase separation at the interfaces. After the 600 deg. C annealing, ion irradiation (Ar ions, 300 keV 1x1015 ions/cm2) causes an additional increase of the bilayer repeat length but a decrease of the quality of the interface. After annealing at 800 deg. C or 1000 deg. C, the irradiation causes a major decrease of the bilayer repeat length (more than 20% after annealing at 1000 deg. C and irradiation). The stress is highly compressive after deposition (σ=-2000 MPa). After the 600 deg. C annealing, the stress is totally relaxed (σ=0) and becomes tensile after annealing at higher temperatures (σ=+1200 MPa after 800 deg. C annealing, σ=+1500 MPa after 1000 deg. C annealing). TEM confirms the decrease of the bilayer repeat length after an irradiation of the samples subjected to high temperature anneal and reveal an increase of the roughness of the interfaces. These phenomena are discussed in terms of stress driven diffusion during irradiation

  11. The Simulated Annealing Algorithm Implemented by the MATLAB

    Directory of Open Access Journals (Sweden)

    Lin Lin

    2012-11-01

    Full Text Available This paper expounds the basic principle of simulated annealing algorithm which was applied to solve the function optimization problem and the algorithm realization process by using MATLAB language. Through the improvement algorithm results show that the method is able to function for global optimization, effectively overcome the based on the derivative of the optimization algorithm easy to fall into local optimum problems. This method not only can deepen the understanding of the simulated annealing process, but also can achieve the purpose of design intelligent system.

  12. Adiabatic quantum computation and quantum annealing theory and practice

    CERN Document Server

    McGeoch, Catherine C

    2014-01-01

    Adiabatic quantum computation (AQC) is an alternative to the better-known gate model of quantum computation. The two models are polynomially equivalent, but otherwise quite dissimilar: one property that distinguishes AQC from the gate model is its analog nature. Quantum annealing (QA) describes a type of heuristic search algorithm that can be implemented to run in the ``native instruction set'''' of an AQC platform. D-Wave Systems Inc. manufactures {quantum annealing processor chips} that exploit quantum properties to realize QA computations in hardware. The chips form the centerpiece of a nov

  13. Simulated annealing optimization for multi-objective economic dispatch solution

    Directory of Open Access Journals (Sweden)

    Ismail ZIANE

    2014-11-01

    Full Text Available This paper presents a multi-objective Simulated Annealing Optimization to solve a Dynamic Generation Dispatch problem. In this work, the problem is formulated as a multi-objective one with two competing functions, namely economic cost and emission functions, subject to different constraints. The inequality constraints considered are the generating unit capacity limits while the equality constraint is generation-demand balance. To show the advantages of the proposed algorithm, it has been applied for solving multi-objective EELD problems in a 3-generator system with NOx and SO2 emission. Results obtained with Simulated Annealing have been compared with other existing relevant approaches available in literatures. Experimental results show a proficiency of Simulated Annealing over other existing techniques in terms of robustness.

  14. Solving the Optimal Trading Trajectory Problem Using a Quantum Annealer

    Science.gov (United States)

    Rosenberg, Gili; Haghnegahdar, Poya; Goddard, Phil; Carr, Peter; Wu, Kesheng; de Prado, Marcos Lopez

    2016-09-01

    We solve a multi-period portfolio optimization problem using D-Wave Systems' quantum annealer. We derive a formulation of the problem, discuss several possible integer encoding schemes, and present numerical examples that show high success rates. The formulation incorporates transaction costs (including permanent and temporary market impact), and, significantly, the solution does not require the inversion of a covariance matrix. The discrete multi-period portfolio optimization problem we solve is significantly harder than the continuous variable problem. We present insight into how results may be improved using suitable software enhancements, and why current quantum annealing technology limits the size of problem that can be successfully solved today. The formulation presented is specifically designed to be scalable, with the expectation that as quantum annealing technology improves, larger problems will be solvable using the same techniques.

  15. Flash memory ionizing radiation effects and annealing characteristics

    International Nuclear Information System (INIS)

    Background: Studies of the radiation effects on the floating-gate flash memory have been mainly focused on functionality measurement. Purpose: According to the present situation, flash memory was irradiated and annealed by 60Co γ rays, and the TID failure mechanism of the device was analyzed. Methods: The function parameters including DC and AC were measured using a large scale integrated circuit testing system. The range of radiation-sensitive parameters was extended using the Verigy 93000 instrument and the Shmoo test. Results: The results showed that the maximum operating frequency was radiation-sensitive parameter which has a significant change in radiation and annealing. Conclusions: Under strong electric field, due to the accumulation of oxide trapped charge and interface trap charge, the performance of charge pump circuit was deteriorated and the function of device was failed. Annealing characteristics indicated that the oxide trapped charge accounts for a major role. (authors)

  16. Coordination Hydrothermal Interconnection Java-Bali Using Simulated Annealing

    Science.gov (United States)

    Wicaksono, B.; Abdullah, A. G.; Saputra, W. S.

    2016-04-01

    Hydrothermal power plant coordination aims to minimize the total cost of operating system that is represented by fuel costand constraints during optimization. To perform the optimization, there are several methods that can be used. Simulated Annealing (SA) is a method that can be used to solve the optimization problems. This method was inspired by annealing or cooling process in the manufacture of materials composed of crystals. The basic principle of hydrothermal power plant coordination includes the use of hydro power plants to support basic load while thermal power plants were used to support the remaining load. This study used two hydro power plant units and six thermal power plant units with 25 buses by calculating transmission losses and considering power limits in each power plant unit aided by MATLAB software during the process. Hydrothermal power plant coordination using simulated annealing plants showed that a total cost of generation for 24 hours is 13,288,508.01.

  17. Rapid Thermal annealing of silicon layers amorphized by ion implantation

    International Nuclear Information System (INIS)

    The recrystallization behavior and the supression mechanisms of the residual defects of silicon layers amorphized by ion implantation, were investigated. The samples were annealed with the aid of a rapid thermal annealing (RTA) system at temperature range from 850 to 12000C, and annealing time up to 120 s. Random and aligned Rutherford backscattering spectroscopy were used to analyse the samples. Similarities in the recrystallization behavior for layers implanted with ions of the same chemical groups such as As or Sb; Ge, Sn or Pb, In or Ga, are observed. The results show that the effective supression of resisual defects of the recrystallired layers is vinculated to the redistribution of impurities via thermal diffusion. (author)

  18. Effect of Annealing on Rare Earth Based Hydrogen Storage Alloys

    Institute of Scientific and Technical Information of China (English)

    Li Jinhua

    2004-01-01

    Rare earth-based hydrogen storage alloy used as negative electrode materials for nickel-metal hydride (Ni-MH) batteries are used commercially.The effect of annealing treatment with different annealing temperature and time on the MLNi3.68 Co0.78 Mn0.35 Al0.27 and MMNi3.55 Co0.75 Mn0.40 Al0.30 alloys were investigated.The crystal microstructure,pressure-composition-isotherms (p-C-T) and electrochemical properties of alloys were examined by X-ray diffraction (XRD), automatic PCI monitoring system and electrical performance testing instruments.The optimum annealing treatment conditions of two kinds of alloys were determined.

  19. Influence of annealing temperature on the magnetic properties of Cr{sup +} implanted AlN thin films

    Energy Technology Data Exchange (ETDEWEB)

    Shah, A., E-mail: attaullah77@yahoo.com [National Institute of Lasers and Optronics (NILOP), PO Nilore, Islamabad (Pakistan); Mahmood, Arshad; Ali, Zahid; Ashraf, T. [National Institute of Lasers and Optronics (NILOP), PO Nilore, Islamabad (Pakistan); Ahmed, Ishaq [Experimental Physics Lab, National Center for Physics (NCP), Islamabad (Pakistan); Mehmood, Mazhar [DMME, Pakistan Institute of Engineering and Applied Science (PIEAS), PO Nilore, Islamabad Pakistan (Pakistan); Rashid, Rashad [National Institute of Lasers and Optronics (NILOP), PO Nilore, Islamabad (Pakistan); Shakir, Imran, E-mail: shakir@skku.edu [Sustainable Energy Technologies (SET) center building No 3, Room 1c23, College of Engineering, King Saud University, PO-BOX 800, Riyadh 11421 (Saudi Arabia)

    2015-04-01

    Diluted magnetic semiconductor (DMS) AlN:Cr films were produced by implanting various doses Cr{sup +} ions into AlN thin films at room temperature followed by a thermal annealing process. The structural and magnetic characteristics of the samples were investigated as a function of annealing temperature by means of Rutherford backscattering and channeling spectrometry (RBS/C), X-ray diffraction (XRD), Raman spectroscopy, vibrating sample magnetometer (VSM) and SQUID. Structural analyzes demonstrate that implantation damages gradually decrease with the increasing of annealing temperature. Moreover, better recrystallization in the implanted part of the samples was observed for the sample annealed at 950 °C. Both XRD and Raman pattern illustrate that no secondary phase or metal related-peaks were appear in all the samples. Magnetic analysis reveals that annealed Cr{sup +}-implanted samples exhibit ferromagnetism at room temperature, however, the sample annealed at 950 °C shows improved magnetic characteristics. The saturation magnetization is estimated to be 9.0×10{sup −5} emu/g and the coercive field (H{sub c}) is approximately 200 Oe for the samples annealed 950 °C. In SQUID analysis, FC/ZFC measurements indicate that the Curie temperature (T{sub C}) is well above room temperature.

  20. Picosecond laser annealing of silicon

    International Nuclear Information System (INIS)

    The existing literature is reviewed and new results are presented on the regrowth of silicon surfaces, either virgin or amorphized by ion-implantation, following irradiation by picosecond laser pulses. The importance of melt depth, quench rate and the nature of the initial a-Si surface as revealed by cross-section TEM are emphasized in order to explain the unique halo patterns observed optically. A search for plasma annealing phenomena, as well as evidence for the buried molten layer proposed by other authors, both proved negative. (author)

  1. Loviisa Unit One: Annealing - healing

    Energy Technology Data Exchange (ETDEWEB)

    Kohopaeae, J.; Virsu, R. [ed.; Henriksson, A. [ed.

    1997-11-01

    Unit 1 of the Loviisa nuclear powerplant was annealed in connection with the refuelling outage in the summer of 1996. This type of heat treatment restored the toughness properties of the pressure vessel weld, which had been embrittled be neutron radiation, so that it is almost equivalent to a new weld. The treatment itself was an ordinary metallurgical procedure that took only a few days. But the material studies that preceded it began over fifteen years ago and have put IVO at the forefront of world-wide expertise in the area of radiation embrittlement

  2. Dilution of molybdenum on aluminum during laser surface alloying

    International Nuclear Information System (INIS)

    Highlights: •Laser surface alloying significantly increased the solubility of transition metal. •Laser surface alloying produced dense coating with good metallurgical bonding. •Laser process parameters greatly influenced the evolution of various intermetallics. •Computationally predicted results closely matched with experimental findings. •Ability to generalize present model to other metal-transition metal systems. -- Abstract: A multiphysics based computational model was developed to predict the dilution of molybdenum (Mo) on an aluminum (Al) substrate during the laser surface alloying process. The influence of laser surface alloying processing parameters such as input energy, scanning speed, and overlapping ratio on dilution of Mo in Al was explored via computational model. The computational model, closely predicts the melt pool geometry (width and depth) that subsequently helps in estimating dilution. It was observed that the dilution increases with the increase in laser power, while it decreases with the increase in scanning speed. The phase and microstructural analyses revealed the existence of Al5Mo intermetallic for most of the laser surface alloying processing conditions. However, at higher (3.18 × 107 J/m2) and lower (1.91 × 107 J/m2) laser energy densities, the Al8Mo3 intermetallic was also evolved. These experimental observations validate the model’s predictions and points to its reliability in predicting the expected intermetallics in Al–Mo system for various laser surfacing alloying processing conditions

  3. Annealing Polymer Nanocomposite Fibers and Films Via Photothermal Heating: Effects On Overall Crystallinity and Morphology

    Science.gov (United States)

    Viswanath, Vidya

    Metal nanoparticles embedded within polymeric systems can act as localized heat sources, facilitating in situ polymer processing. When irradiated with light resonant with the nanoparticle's surface plasmon resonance (SPR), a non-equilibrium electron distribution is generated which rapidly transfers energy into the surrounding medium, resulting in a temperature increase in the immediate region around the particle. This work compares the utility of such photothermal heating versus traditional heating in two different polymeric media i.e. gold nanospheres/poly (ethylene oxide) (AuNP:PEO) nanocomposite films and electrospun nanofibers. Subsequently, a brief study on the usage of gold nanorods (AuNR) to anneal polymeric nanofibers and films has also been presented. Effect of annealing by conventional and photothermal methods has been studied for AuNP:PEO films crystallized from solution and the melt, which have been annealed at average sample temperatures above the glass transition and below the melting point. For all temperatures, photothermally annealed samples reached maximum crystallinity and maximum spherulite size at shorter annealing times. Percentage crystallinity change under conventional annealing was analyzed using time-temperature superposition (TTS). Comparison of the TTS data with results from photothermal experiments enabled determination of an "effective dynamic temperature" achieved under photothermal heating which is significantly higher than the average sample temperature. Thus, the heterogeneous temperature distribution created when annealing with the plasmon-mediated photothermal effect represents a unique tool to achieve processing outcomes that are not accessible via traditional annealing. In addition, the effect of annealing AuNP:PEO electrospun nanofibrous composites via conventional and photothermal annealing has also been studied. From the studies, it was observed that not only is the maximum crystallinity achieved more quickly when the

  4. Reverse annealing of boron doped polycrystalline silicon

    International Nuclear Information System (INIS)

    Thermal activation was carried out using polycrystalline silicon (poly-Si) produced through sequential-lateral-solidification or excimer-laser-crystallization (ELC) after B+ ion shower doping. The activation efficiency of the ELC samples was found to be higher than that of the SLS ones. In this regard, grain boundaries seemed to play a critical role in terms of the activation of dopants in poly-Si at low temperatures. Reverse annealing, in which a continuous loss of charge carriers occurs, was found in this study at temperatures ranging between 400 oC and 650 oC. The samples treated by rapid thermal annealing showed a lower sheet resistance than those treated by furnace annealing. Rapid thermal annealing was found to exhibit a higher activation efficiency than furnace annealing. Reverse annealing is believed to play an important role in terms of activation efficiency

  5. Reverse annealing of boron doped polycrystalline silicon

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Beop-Jong; Hong, Won-Eui [Department of Materials Science and Engineering, Hongik University, Seoul, 121-791 (Korea, Republic of); Kim, Deok Hoi; Uemoto, Tstomu; Kim, Chi Woo [LTPS Team, AMLCD Business, Samsung Electronics, Yongin-City, Gyeonggi-Do, 449-711 (Korea, Republic of); Ro, Jae-Sang [Department of Materials Science and Engineering, Hongik University, Seoul, 121-791 (Korea, Republic of)], E-mail: jsang@wow.hongik.ac.kr

    2008-07-31

    Thermal activation was carried out using polycrystalline silicon (poly-Si) produced through sequential-lateral-solidification or excimer-laser-crystallization (ELC) after B{sup +} ion shower doping. The activation efficiency of the ELC samples was found to be higher than that of the SLS ones. In this regard, grain boundaries seemed to play a critical role in terms of the activation of dopants in poly-Si at low temperatures. Reverse annealing, in which a continuous loss of charge carriers occurs, was found in this study at temperatures ranging between 400 {sup o}C and 650 {sup o}C. The samples treated by rapid thermal annealing showed a lower sheet resistance than those treated by furnace annealing. Rapid thermal annealing was found to exhibit a higher activation efficiency than furnace annealing. Reverse annealing is believed to play an important role in terms of activation efficiency.

  6. Ferromagnetism in diluted magnetic semiconductor heterojunction systems

    Czech Academy of Sciences Publication Activity Database

    Lee, B.; Jungwirth, Tomáš; MacDonald, A. H.

    2002-01-01

    Roč. 17, - (2002), s. 393-403. ISSN 0268-1242 R&D Projects: GA ČR GA202/98/0085; GA MŠk OC P5.10 Institutional research plan: CEZ:AV0Z1010914 Keywords : ferromagnetic semiconductors * heterostructures Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.241, year: 2002

  7. Effective Field Theory for Dilute Fermi Systems

    OpenAIRE

    Hammer, H. -W.; Furnstahl, R. J.

    2000-01-01

    The virtues of an effective field theory (EFT) approach to many-body problems are illustrated by deriving the expansion for the energy of an homogeneous, interacting Fermi gas at low density and zero temperature. A renormalization scheme based on dimensional regularization with minimal subtraction leads to a more transparent power-counting procedure and diagrammatic expansion than conventional many-body approaches. Coefficients of terms in the expansion with logarithms of the Fermi momentum a...

  8. Keystream Generator Based On Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Ayad A. Abdulsalam

    2011-01-01

    Full Text Available Advances in the design of keystream generator using heuristic techniques are reported. A simulated annealing algorithm for generating random keystream with large complexity is presented. Simulated annealing technique is adapted to locate these requirements. The definitions for some cryptographic properties are generalized, providing a measure suitable for use as an objective function in a simulated annealing algorithm, seeking randomness that satisfy both correlation immunity and the large linear complexity. Results are presented demonstrating the effectiveness of the method.

  9. Simulated Annealing using Hybrid Monte Carlo

    OpenAIRE

    Salazar, Rafael; Toral, Raúl

    1997-01-01

    We propose a variant of the simulated annealing method for optimization in the multivariate analysis of differentiable functions. The method uses global actualizations via the hybrid Monte Carlo algorithm in their generalized version for the proposal of new configurations. We show how this choice can improve upon the performance of simulated annealing methods (mainly when the number of variables is large) by allowing a more effective searching scheme and a faster annealing schedule.

  10. NEW SIMULATED ANNEALING ALGORITHMS FOR CONSTRAINED OPTIMIZATION

    OpenAIRE

    LINET ÖZDAMAR; CHANDRA SEKHAR PEDAMALLU

    2010-01-01

    We propose a Population based dual-sequence Non-Penalty Annealing algorithm (PNPA) for solving the general nonlinear constrained optimization problem. The PNPA maintains a population of solutions that are intermixed by crossover to supply a new starting solution for simulated annealing throughout the search. Every time the search gets stuck at a local optimum, this crossover procedure is triggered and simulated annealing search re-starts from a new subspace. In both the crossover and simulate...

  11. Magnetoimpedance response in current annealed amorphous wires

    International Nuclear Information System (INIS)

    In this work, the magnetoimpedance (MI) effect in amorphous wires submitted to current annealing treatment in vacuum is presented. The influence of circular anisotropy and stress relaxation induced during the annealing on the impedance dependence on external magnetic field is shown. An increase in the MI ratio for the annealed wires is observed up to a maximum value which is approximately three times higher than the maximum value obtained for the as-cast wire. For high enough times of current annealing treatment a decrease in the MI ratio is observed due to the formation of crystalline phase

  12. Magnetoimpedance response in current annealed amorphous wires

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, D. [Dpto. Fisica Aplicada, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain)]. E-mail: danielgg@usal.es; Raposo, V. [Dpto. Fisica Aplicada, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain); Borza, F. [Wolfson Centre for Magnetics Technology, Cardiff University, New Port Road, P.O. Box 925, CF24 0YF Cardiff (United Kingdom); Montero, O. [Dpto. Fisica Aplicada, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain); Iniguez, J. [Dpto. Fisica Aplicada, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain)

    2006-09-15

    In this work, the magnetoimpedance (MI) effect in amorphous wires submitted to current annealing treatment in vacuum is presented. The influence of circular anisotropy and stress relaxation induced during the annealing on the impedance dependence on external magnetic field is shown. An increase in the MI ratio for the annealed wires is observed up to a maximum value which is approximately three times higher than the maximum value obtained for the as-cast wire. For high enough times of current annealing treatment a decrease in the MI ratio is observed due to the formation of crystalline phase.

  13. Rapid Annealing Of Amorphous Hydrogenated Carbon

    Science.gov (United States)

    Alterovitz, Samuel A.; Pouch, John J.; Warner, Joseph D.

    1989-01-01

    Report describes experiments to determine effects of rapid annealing on films of amorphous hydrogenated carbon. Study represents first efforts to provide information for applications of a-C:H films where rapid thermal processing required. Major finding, annealing causes abrupt increase in absorption and concomitant decrease in optical band gap. Most of change occurs during first 20 s, continues during longer annealing times. Extend of change increases with annealing temperature. Researchers hypothesize abrupt initial change caused by loss of hydrogen, while gradual subsequent change due to polymerization of remaining carbon into crystallites or sheets of graphite. Optical band gaps of unannealed specimens on silicon substrates lower than those of specimens on quartz substrates.

  14. Homeopathic and high dilution preparations for pest management to tomato crop under organic production system Manejo fitossanitário do tomateiro com uso de preparados homeopáticos e altas diluições sob sistema orgânico de produção

    OpenAIRE

    Tatiani A Modolon; Pedro Boff; Mari Inês C. Boff; David José Miquelluti

    2012-01-01

    Tomato crops (Solanum lycopersicum) under conventional production system are constantly treated against pest and diseases, with organic synthetic pesticides that are used may cause serious disturbance to environment and human health. This research was carried out in order to study the effect of homeopathic and high dilution preparations on pests and diseases management of tomato crop under organic production system. Two experiments were conducted under field conditions and one in greenhouse. ...

  15. Isotopic dilution of 233U with depleted uranium for criticality safety in processing and disposal

    International Nuclear Information System (INIS)

    The disposal of excess 233U as waste is being considered. Because 233U is a fissile material, a key requirement for processing 233U to a final waste form and disposing of it is the avoidance of nuclear criticality. For many processing and disposal options, isotopic dilution is the most feasible and preferred option to avoid nuclear criticality. Isotopic dilution is dilution of fissile 233U with nonfissile 238U. The use of isotopic dilution removes any need to control nuclear criticality in process or disposal facilities through geometry or chemical composition. Isotopic dilution allows the use of existing waste management facilities that are not designed for significant quantities of fissile materials to be used for processing and disposing of 233U. The amount of isotopic dilution required to reduce criticality concerns to reasonable levels was determined in this study to be approximately 0.53 wt % 233U. The numerical calculations used to define this limit consisted of a homogeneous system of silicon dioxide (SiO2), water (H2O), 233U and depleted uranium (DU) in which the ratio of each component was varied to learn the conditions of maximum nuclear reactivity. About 188 parts of DU (0.2 wt % 235U) are required to dilute 1 part of 233U to this limit in a water-moderated system with no SiO2 present. Thus for the U.S. inventory of 233U, several hundred metric tons of DU would be required for isotopic dilution

  16. Investigation of point defects after low temperature irradiation and qenching in diluted W57Co alloys

    International Nuclear Information System (INIS)

    In high purity tungsten foils and monocrystals with implanted 57Co probe atoms (diluted W-Co alloys) were point defects investigated using Moessbauer spectroscopy and resistivity measurements. The point defects were produced by irradiation with reactor neutrons, with 3 MeV electrons, or by quenching. It is shown that in irradiated samples moving interstitials and vacancies can be trapped by motionless 57Co atoms. Annealing of point defects was performed in the temperature range from 4.2 K to 1683 K. (GSCH)

  17. Therapeutic possibilities of Bothrops jararaca in high dilution

    Directory of Open Access Journals (Sweden)

    Eduardo Costa Gaia Nazareth

    2011-09-01

    Full Text Available Introduction: The knowledge and use of the venom of Bothrops jararaca in high dilutions is still quite limited. One of the important properties is the use of one of its components, bradykinin, for the development of antihypertensive medication known as captopril. Other situations, such as clinical, local and systemic should receive more depth to the composition of Materia Medica related to various medical actions on the man and mammals in general. The systemic action of the bite of this snake, includes hemostasis disorders, culminating as bleeding gums, in addition to sweating, hypertension, and hypothermia. The action includes local pain and swelling with bruising, bleeding and often blistering and tissue necrosis. The action on the immune system, through action on the complement C3 and other complement components may show its possible use in cases of bacterial infections, including mycobacteria, as presented in the study of 1970 Vanessa Birdsey, "Interactions of poisons toxic with the addition, "the journal of Immunology 1971. Today, this poison has a toxicology published by Anibal Melgarejo, "Venomous Animals of Brazil", 2003, which subsidizes the development of study for its use in high dilutions, and a comprehensive study of the biology of the animal itself. Published studies on biomolecular analysis add more details about the relations of the poison and mammals. All these characteristics suggest the use of poison as a homeopathic remedy. Objective: To investigate the therapeutic possibilities in high dilutions of the venom of the snake Bothrops jararaca, expanding its clinical use. Methodology: Methodological description of this poison in contemporary bases including: Origin, physical description chemistry, toxicology, pharmacology and medicine in preparation of high dilution, general action, specific actions on systems or organs, sensations, modalities, concomitants, etiological indications relations main clinics. Results: Defining

  18. DOE`s annealing prototype demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Warren, J.; Nakos, J.; Rochau, G.

    1997-02-01

    One of the challenges U.S. utilities face in addressing technical issues associated with the aging of nuclear power plants is the long-term effect of plant operation on reactor pressure vessels (RPVs). As a nuclear plant operates, its RPV is exposed to neutrons. For certain plants, this neutron exposure can cause embrittlement of some of the RPV welds which can shorten the useful life of the RPV. This RPV embrittlement issue has the potential to affect the continued operation of a number of operating U.S. pressurized water reactor (PWR) plants. However, RPV material properties affected by long-term irradiation are recoverable through a thermal annealing treatment of the RPV. Although a dozen Russian-designed RPVs and several U.S. military vessels have been successfully annealed, U.S. utilities have stated that a successful annealing demonstration of a U.S. RPV is a prerequisite for annealing a licensed U.S. nuclear power plant. In May 1995, the Department of Energy`s Sandia National Laboratories awarded two cost-shared contracts to evaluate the feasibility of annealing U.S. licensed plants by conducting an anneal of an installed RPV using two different heating technologies. The contracts were awarded to the American Society of Mechanical Engineers (ASME) Center for Research and Technology Development (CRTD) and MPR Associates (MPR). The ASME team completed its annealing prototype demonstration in July 1996, using an indirect gas furnace at the uncompleted Public Service of Indiana`s Marble Hill nuclear power plant. The MPR team`s annealing prototype demonstration was scheduled to be completed in early 1997, using a direct heat electrical furnace at the uncompleted Consumers Power Company`s nuclear power plant at Midland, Michigan. This paper describes the Department`s annealing prototype demonstration goals and objectives; the tasks, deliverables, and results to date for each annealing prototype demonstration; and the remaining annealing technology challenges.

  19. Phase boundary detection for dilution refrigerators

    CERN Document Server

    Haar, E

    2004-01-01

    We describe a device to conveniently measure the positions of the phase boundaries in a dilution refrigerator. We show how a simple modification of a standard capacitive level gauge (segmentation of one of the electrodes) permits a direct calibration of the capacitance versus phase boundary position. We compare this direct calibration with the indirect procedure that must be adopted for a conventional capacitive level gauge. The device facilitates the correct adjustment of the 3He/4He fraction in the dilution refrigerator.

  20. Annealing Reduces Free Volumes In Thermoplastics

    Science.gov (United States)

    Singh, Jag J.; St. Clair, Terry L.

    1988-01-01

    Investigation conducted to determine free volumes and water-absorption characteristics of two types of thermoplastic polymide as functions of annealing histories. Reductions reach asymptotic values after several annealing cycles. High-temperature thermoplastics excellent candidates for use in aerospace applications. Graphite-fiber composites containing thermoplastic matrices have wide applicability.

  1. Measurement of N2 fixation in Sesbania aculeata pers. and Sorghum bicolor L. grown in intercropping system, using sup 1 sup 5 N isotopic dilution technique. 1: Field evaluation under non-saline conditions

    International Nuclear Information System (INIS)

    A field experiment on Sesbania aculeata and Sorghum bicolor grown in mono cropping and in inter cropping systems was conducted under non-saline conditions (soil EC sub e 0.16, water EC sub w 1 ds/m/m) to evaluate dry matter production, total N yield, soil N uptake and N sub 2 -fixation using sup 1 sup 5 N isotope dilution method. Three different row ratios of sesbania (ses) and sorghum (sor) were subjected in the inter cropping system (2 ses: 1 sor; 1 ses: 1 sor and 1 ses: 2 sor row ratio). Dry matter yield of sole sorghum was higher than that of sole sesbania, and it was similar to that produced by the inter cropping treatments. However, total N yield of sole sorghum was significantly the lowest, with no differences being obtained between sole sesbania and inter cropping treatments. The LERs of total N yield were, in all cases, higher than 1, reflecting a greater advantage of inter cropping system in terms of land use efficiency. Percentages of N sub 2 fixation in the inter cropped sesbania were considerably enhanced compared with the pure stand of sesbania. This was mainly attributed to the depletion of soil N resulting from the greater apparent competitiveness of sorghum for soil N, and consequently, a greater dependence of sesbania on N sub 2 fixation. However, the degree of the intraspecific competition for soil N uptake was affected by the proportion of crops in the mixture, and it was considerably reduced in the 2 ses: 1 sor row ratio. This was demonstrated when an equal depletion of soil and fertilizer N uptake occurred for both crops. We excluded in all-inter cropping treatments the possibility of N transfer from sesbania to sorghum. Row inter cropping, with crops grown in alternation of two rows of sesbania with one row of sorghum, seemed to be the most adequate row ratio in terms of total N yield, LER, N sub 2 -fixation and soil N uptake balance of the component crops. (author)

  2. Ground-state statistics from annealing algorithms: Quantum vs classical approaches

    OpenAIRE

    Matsuda, Yoshiki; Nishimori, Hidetoshi; Katzgraber, Helmut G.

    2008-01-01

    We study the performance of quantum annealing for systems with ground-state degeneracy by directly solving the Schr\\"odinger equation for small systems and quantum Monte Carlo simulations for larger systems. The results indicate that naive quantum annealing using a transverse field may not be well suited to identify all degenerate ground-state configurations, although the value of the ground-state energy is often efficiently estimated. An introduction of quantum transitions to all states with...

  3. Analytical and experimental research into boron dilution events

    International Nuclear Information System (INIS)

    Research activities are being performed in Germany with the aim to improve and validate the methods for predicting boron dilution events. Integral experiments in the PKL test facility investigate the thermal-hydraulic system behaviour in a wide range of conditions. The latest test program comprises small break LOCA scenarios with boron dilution. For these tests, boric acid in the coolant is used together with an advanced instrumentation that can measure boron concentration during the transient. Mixing processes in the downcomer and lower plenum under the influence of various loop operating conditions are studied in the transparent 1:5 ROCOM four-loop test facility equipped with advanced wire mesh sensors to follow the transient concentration patterns. Analytical R and D activities include further model development and validation in the thermal-hydraulic system code ATHLET as well as assessment calculations for detailed three-dimensional mixing in the reactor pressure vessel with CFD-codes. (authors)

  4. Spin currents in diluted magnetic semiconductors

    International Nuclear Information System (INIS)

    We report on the observation of spin currents resulting in the zero-bias spin separation in unbiased diluted magnetic semiconductor structures. We demonstrate that an absorption of THz radiation in (001)-grown (Cd,Mn)Te/(Cd,Mg)Te QWs with Mn2+ magnetic ions leads to a pure spin current. The effect is investigated in a magnetic field converting the spin separation into a net electric current. We demonstrate that the polarization of the magnetic ion system enhances drastically the conversion due to the spin-dependent scattering by localized Mn2+ ions and the giant Zeeman splitting. Both effects disturb the balance of the oppositely directed spin-polarized flows yielding an electric current. In weak magnetic fields for a degenerated electron gas the scattering mechanism dominates the current conversion. We show that the spin-dependent exchange scattering of electrons by magnetic impurities plays an important role in the current generation providing a handle to manipulate the spin-polarized currents.

  5. Studies of deep-level defects in flash lamp annealing of ion-implanted silicon

    International Nuclear Information System (INIS)

    The spatial uniformity and in-depth profile of phosphorus-ion-implanted silicon annealed by flash lamps were studied with Hall effect, spreading resistance and minority-carrier lifetime measurements. Deep levels in flash-lamp-annealed n+p diodes were examined using deep-level transient spectroscopy (DLTS) and reverse current measurements. A uniformly annealed area, about 40x40 mm2, was obtained, which coincided with the uniformly light-irradiated area of the flash lamp annealing system. In n+p diodes, two hole traps H1(Esub(v)+0.39 eV) and H2(Esub(v)+0.46 eV) were observed at 26 J cm-2, and two hole traps H1(Esub(v)+0.39 eV) and H3(Esub(v)+0.47 eV) were observed at 20 J cm-2. The spatial reverse current distributions within the wafer were similar to those of H2 defects. To remove these residual defects in diodes, effects of the additional furnace annealing and the multiple-shot irradiations were also investigated. H1 defects were annealed out with 7000C additional furnace heating for 30 min. H1 and H2 defects of 26 J cm-2 flash-lamp-annealed samples were annealed out by two-shot flash lamp irradiations. (author)

  6. High-Throughput ab-initio Dilute Solute Diffusion Database

    OpenAIRE

    Wu, Henry; Mayeshiba, Tam; Morgan, Dane

    2016-01-01

    We demonstrate automated generation of diffusion databases from high-throughput density functional theory (DFT) calculations. A total of more than 230 dilute solute diffusion systems in Mg, Al, Cu, Ni, Pd, and Pt host lattices have been determined using multi-frequency diffusion models. We apply a correction method for solute diffusion in alloys using experimental and simulated values of host self-diffusivity. We find good agreement with experimental solute diffusion data, obtaining a weighte...

  7. Ab-initio calculations for dilute magnetic semiconductors

    OpenAIRE

    Belhadji, Brahim

    2008-01-01

    This thesis focusses on ab-initio calculations for the electronic structure and the magnetic properties of dilute magnetic semiconductors (DMS). In particular we aim at the understanding of the complex exchange interactions in these systems. Our calculations are based on density functional theory, being ideally suited for a description of the material specific properties of the considered DMS. Moreover we use the KKR Green function method in connection with the coherent potential approximatio...

  8. Biodiversity inhibits parasites: Broad evidence for the dilution effect

    OpenAIRE

    Civitello, David J.; Cohen, Jeremy; Fatima, Hiba; Halstead, Neal T.; Liriano, Josue; McMahon, Taegan A.; Ortega, C. Nicole; Sauer, Erin Louise; Sehgal, Tanya; Young, Suzanne; Rohr, Jason R.

    2015-01-01

    The dilution effect hypothesis suggests that diverse ecological communities limit disease spread via several mechanisms. Therefore, biodiversity losses could worsen epidemics that harm humans and wildlife. However, there is contentious debate over whether the hypothesis applies broadly, especially for parasites that infect humans. We address this fundamental question with a formal meta-analysis of >200 assessments relating biodiversity to disease in >60 host–parasite systems. We find overwhel...

  9. Influence of thermal annealing and ion irradiation on zinc silicate phases in nanocomposite ZnO–SiOx thin films

    International Nuclear Information System (INIS)

    Highlights: • Nc ZnO–SiOx thin films were grown by rf magnetron sputtering. • Rhombohedral zinc silica phase formed in annealed thin films. • Dilution of zinc silicate phases observed in the irradiated thin films. • Visible PL emission due to defects in ZnO changed with ion fluence. • The results are explained in terms of possible ion beam effects in the material. - Abstract: The formation of zinc silicate phase in nanocomposite (nc) ZnO–SiOx thin films, its dilution by ion irradiation and subsequent developments were investigated. The nc ZnO–SiOx thin films used in the study were grown using rf magnetron sputter deposition on silicon (Si) substrates. Thin films were also grown on transmission electron microscopy (TEM) grids in identical conditions. The as-deposited films on Si substrates were annealed at 750 and 900 °C in air for growth of crystalline zinc silicate phase. The as-deposited and 750 °C annealed films were irradiated with 50 MeV oxygen ions in the fluence range from 5 × 1011 to 1 × 1014 ions cm−2. The presence of zinc silicate was observed by X-ray diffraction (XRD) analysis of the annealed films and by Fourier transform infrared (FT-IR) spectroscopy measurements. XRD and FT-IR analyses of the films show increase in zinc silicate phase with annealing and dilution of zinc silicate phase with irradiation. Photoluminescence (PL) analysis of irradiated as-deposited films show change in defects of ZnO. The results are explained in terms of possible ion irradiation induced modifications in the material

  10. Cortical attractor network dynamics with diluted connectivity.

    Science.gov (United States)

    Rolls, Edmund T; Webb, Tristan J

    2012-01-24

    The connectivity of the cerebral cortex is diluted, with the probability of excitatory connections between even nearby pyramidal cells rarely more than 0.1, and in the hippocampus 0.04. To investigate the extent to which this diluted connectivity affects the dynamics of attractor networks in the cerebral cortex, we simulated an integrate-and-fire attractor network taking decisions between competing inputs with diluted connectivity of 0.25 or 0.1, and with the same number of synaptic connections per neuron for the recurrent collateral synapses within an attractor population as for full connectivity. The results indicated that there was less spiking-related noise with the diluted connectivity in that the stability of the network when in the spontaneous state of firing increased, and the accuracy of the correct decisions increased. The decision times were a little slower with diluted than with complete connectivity. Given that the capacity of the network is set by the number of recurrent collateral synaptic connections per neuron, on which there is a biological limit, the findings indicate that the stability of cortical networks, and the accuracy of their correct decisions or memory recall operations, can be increased by utilizing diluted connectivity and correspondingly increasing the number of neurons in the network, with little impact on the speed of processing of the cortex. Thus diluted connectivity can decrease cortical spiking-related noise. In addition, we show that the Fano factor for the trial-to-trial variability of the neuronal firing decreases from the spontaneous firing state value when the attractor network makes a decision. This article is part of a Special Issue entitled "Neural Coding". PMID:21875702

  11. Water in oil microemulsions : criteria for dilution at constant droplet size

    OpenAIRE

    Cazabat, A.M.

    1983-01-01

    The validity of the customary method for diluting water in oil (w/o) microemulsions is discussed. In concentrated systems and in the vicinity of critical consolute points, the method has deficiencies.

  12. Investigation of annealing techniques for aluminum implanted layers in 4H-silicon carbide

    International Nuclear Information System (INIS)

    This thesis discusses annealing techniques for aluminum implanted layers in 4H-silicon carbide. The purpose is to minimize the surface degradation and to maximize the degree of activation for the implanted atoms. Annealing temperatures necessary for aluminum implanted layers are about 1700 C. Therefore, surface degradation was examined for two different annealing systems. First, a special developed vertical furnace was used with the possibility to add silane during annealing in order to control the silicon partial pressure. The result was a reduced surface degradation. Further reduction of the surface degradation was possible by using implantation temperatures up to 1000 C. A decrease in the surface roughness of about 40% down to 12 nm was achieved for an implantation dose of 1.2.1015 cm-2. The second annealing system investigated was a lamp heated furnace. The sample was put into a box system during annealing. Due to evaporation of box material during annealing, a controlled annealing atmosphere could be achieved by using an appropriate box material. The lowest surface roughness was obtained by annealing in a silicon carbide coated graphite box. An implantation dose of 1.2.1015 cm-2 resulted in a surface roughness of 5 nm. For electrical characterization, a model for calculating resistivity was developed. The base of this model was the neutrality equation for calculating free carrier concentrations and an improved Thomas-Caughey model for mobility determination. Using this model, the degree of activation and the compensation ratio were calculated based on temperature dependent resistivity measurements. The activation degree is larger and the compensation ratio is smaller for annealing in the vertical furnace compared to the lamp system for the same annealing temperature. This is due to the longer annealing time of 30min instead of times between 20s and 5min. Annealing at 1700 C for 30min resulted in a 100% activation and a compensation ratio of 33%. By using

  13. Cylinder packing by simulated annealing

    Directory of Open Access Journals (Sweden)

    M. Helena Correia

    2000-12-01

    Full Text Available This paper is motivated by the problem of loading identical items of circular base (tubes, rolls, ... into a rectangular base (the pallet. For practical reasons, all the loaded items are considered to have the same height. The resolution of this problem consists in determining the positioning pattern of the circular bases of the items on the rectangular pallet, while maximizing the number of items. This pattern will be repeated for each layer stacked on the pallet. Two algorithms based on the meta-heuristic Simulated Annealing have been developed and implemented. The tuning of these algorithms parameters implied running intensive tests in order to improve its efficiency. The algorithms developed were easily extended to the case of non-identical circles.Este artigo aborda o problema de posicionamento de objetos de base circular (tubos, rolos, ... sobre uma base retangular de maiores dimensões. Por razões práticas, considera-se que todos os objetos a carregar apresentam a mesma altura. A resolução do problema consiste na determinação do padrão de posicionamento das bases circulares dos referidos objetos sobre a base de forma retangular, tendo como objetivo a maximização do número de objetos estritamente posicionados no interior dessa base. Este padrão de posicionamento será repetido em cada uma das camadas a carregar sobre a base retangular. Apresentam-se dois algoritmos para a resolução do problema. Estes algoritmos baseiam-se numa meta-heurística, Simulated Annealling, cuja afinação de parâmetros requereu a execução de testes intensivos com o objetivo de atingir um elevado grau de eficiência no seu desempenho. As características dos algoritmos implementados permitiram que a sua extensão à consideração de círculos com raios diferentes fosse facilmente conseguida.

  14. A study on track annealing in Chaoyang No.1 polycarbonate

    International Nuclear Information System (INIS)

    This paper describes annealing characteristics of 208Pb and 93Nb ion tracks in Chaoyang No.1 polycarbonate, including the effect of annealing temperature on track etching rate and the effect of annealing temperature and annealing time on annealing rate. The result shows that activation energy of annealing for 208Pb and 93Nb in Chaoyang No.1 polycarbonate is 0.891 eV and 0.352 eV respectively

  15. Optimizing production of serially diluted compounds and distribution to multiple targets

    OpenAIRE

    2001-01-01

    The need for a multiple-target compound selectivity programme led to the establishment of a single robotic system that produces a compound's serial dilution and its distribution to multiple replicate assay plates. A Genesis RSP 150 integrated into a Zymate Laboratory Automation System XP produced the serial dilutions, and the subsequent replicate assay plates were produced quickly and accurately by an efficient use of the carousels and rapid plate. Currently, this process allows for the produ...

  16. Precision Laser Annealing of Focal Plane Arrays

    Energy Technology Data Exchange (ETDEWEB)

    Bender, Daniel A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); DeRose, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Starbuck, Andrew Lea [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Verley, Jason C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jenkins, Mark W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    We present results from laser annealing experiments in Si using a passively Q-switched Nd:YAG microlaser. Exposure with laser at fluence values above the damage threshold of commercially available photodiodes results in electrical damage (as measured by an increase in photodiode dark current). We show that increasing the laser fluence to values in excess of the damage threshold can result in annealing of a damage site and a reduction in detector dark current by as much as 100x in some cases. A still further increase in fluence results in irreparable damage. Thus we demonstrate the presence of a laser annealing window over which performance of damaged detectors can be at least partially reconstituted. Moreover dark current reduction is observed over the entire operating range of the diode indicating that device performance has been improved for all values of reverse bias voltage. Additionally, we will present results of laser annealing in Si waveguides. By exposing a small (<10 um) length of a Si waveguide to an annealing laser pulse, the longitudinal phase of light acquired in propagating through the waveguide can be modified with high precision, <15 milliradian per laser pulse. Phase tuning by 180 degrees is exhibited with multiple exposures to one arm of a Mach-Zehnder interferometer at fluence values below the morphological damage threshold of an etched Si waveguide. No reduction in optical transmission at 1550 nm was found after 220 annealing laser shots. Modeling results for laser annealing in Si are also presented.

  17. Small angles X-ray diffraction and Mössbauer characterization of annealed Tb/Fe multilayer

    Indian Academy of Sciences (India)

    O M Lemine

    2011-02-01

    The effect of thermal annealing on the structure and magnetic properties of crystalline Tb/Fe multilayers has been studied using conversion electron Mössbauer spectrometry and small-angle X-ray diffraction. The growth of Tb–Fe amorphous alloy from the interface is observed with increasing annealing temperature. After annealing at 873 K, a clear total mixing of the multilayers by interdiffusion has been evidenced. The results are compared with the effect of ion irradiation in the same system.

  18. Impacts of hydrogen dilution on growth and optical properties of a-SiC:H films

    Institute of Scientific and Technical Information of China (English)

    HU; Zhihua; LIAO; Xianbo; DIAO; Hongwei; KONG; Guanglin; Z

    2004-01-01

    Hydrogenated amorphous silicon-carbon (a-SiC:H) films were deposited by plasma enhanced chemical vapor deposition (PECVD) with a fixed methane to silane ratio ([CH4]/[SiH4]) of 1.2 and a wide range of hydrogen dilution (RH=[H2]/[SiH4 + CH4]) values of 12, 22, 33, 102 and 135. The impacts of RH on the structural and optical properties of the films were investigated by using UV-VIS transmission, Fourier transform infrared (FTIR) absorption, Raman scattering and photoluminescence (PL) measur- ements. The effects of high temperature annealing on the films were also probed. It is found that with increasing hydrogen dilution, the optical band gap increases, and the PL peak blueshifts from ~1.43 to 1.62 Ev. In annealed state, the room temperature PL peak for the low RH samples disappears, while the PL peak for the high RH samples appears at ~2.08 Ev, which is attributed to nanocrystalline Si particles confined by Si-C and Si-O bonds.

  19. The kinetic theory of a dilute ionized plasma

    CERN Document Server

    García-Colin, L S

    2008-01-01

    This book results from recent studies aimed at answering questions raised by astrophycists who use values of transport coefficients that are old and often unsatisfactory. The few books dealing with the rigorous kinetic theory of a ionized plasma are based on the so called Landau (Fokker-Planck) equation and they seldom relate the microscopic results with their macroscopic counterpart provided by classical non-equilibrium thermodynamics. In this book both issues are thoroughly covered. Starting from the full Boltzmann equation for inert dilute plasmas and using the Hilbert-Chapman-Enskog method to solve the first two approximations in Knudsen´s parameter, we construct all the transport properties of the system within the framework of linear irreversible thermodynamics. This includes a systematic study of all possible cross effects (which, except for a few cases, were never treated in the literature) as well as the famous H-theorem. The equations of magneto-hydrodynamics for dilute plasmas, including the rathe...

  20. Mössbauer Studies of dilute Magnetic Semiconductors

    CERN Multimedia

    Gislason, H P; Debernardi, A; Dlamini, W B

    2002-01-01

    The recent discovery of (dilute) magnetic semiconductors with wide band gaps, e.g. GaN, ZnO and other oxides, having Curie temperatures, T$_{\\textrm{c}}$, well above room temperature, has prompted extraordinary experimental and theoretical efforts to understand, control and exploit this unexpected finding not least in view of the obvious potential of such materials for the fabrication of "spin-(elec)tronic" or magneto-optic devices. Ferromagnetism (FM) was achieved mostly by doping with dilute 3d transition metal impurities, notably Mn, Fe, and Co (in \\% concentrations), during growth or by subsequent ion implantation. However, it is fair to state that experimentally the conditions for the occurrence of ferro-, antiferro- or paramagnetism with these impurities are not yet controlled as generally at least two conflicting forms of magnetism or none have been reported for each system - albeit often produced by different techniques. Theory is challenged as "conventional" models seem to fail and no generally accep...

  1. Exchange bias in diluted-antiferromagnet/antiferromagnet bilayers

    International Nuclear Information System (INIS)

    The hysteresis-loop properties of a diluted-antiferromagnetic (DAF) layer exchange coupling to an antiferromagnetic (AF) layer are investigated by means of numerical simulations. Remarkable loop shift and coercivity enhancement are observed in such DAF/AF bilayers, while they are absent in the uncoupled DAF single layer. The influences of pinned domains, dilution, cooling field and DAF layer thickness on the loop shift are investigated systematically. The result unambiguously confirms an exchange bias (EB) effect in the DAF/AF bilayers. It also reveals that the EB effect originates from the pinned AF domains within the DAF layer. In contrast to conventional EB systems, frozen uncompensated spins are not found at the interface of the AF pinning layer. (paper)

  2. Monte Carlo Methods for Rough Free Energy Landscapes: Population Annealing and Parallel Tempering

    OpenAIRE

    Machta, Jon; Ellis, Richard S.

    2011-01-01

    Parallel tempering and population annealing are both effective methods for simulating equilibrium systems with rough free energy landscapes. Parallel tempering, also known as replica exchange Monte Carlo, is a Markov chain Monte Carlo method while population annealing is a sequential Monte Carlo method. Both methods overcome the exponential slowing associated with high free energy barriers. The convergence properties and efficiency of the two methods are compared. For large systems, populatio...

  3. Isotope dilution inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    The potential of isotope dilution inductively coupled plasma mass spectrometry (ICP-MS) was evaluated for the determination of trace amounts of uranium and thorium in silicate rocks. Compared with conventional isotope dilution methods using thermal ionization mass spectrometers, the major benefit is a large increase in sample through-put without a significant decrease in precision and accuracy. This results from direct liquid sampling at atmospheric pressure and from the capability of measuring isotope ratios on raw solutions, without chemical separation of the analytes from the matrix elements. Isotope dilution ICP-MS alleviates the need for matrix-matched standards. Further, it is insensitive to possible causes of intensity drift (e.g., clogging of the plasma/mass spectrometer interface and defocusing of the ion beam) and to chemical effects (e.g. oxide formulation). Results obtained on some international rock standards are in good agreement with recommended values. (author). 26 refs.; 1 fig., tabs

  4. Moessbauer-spectroscopic study of structure and magnetism of the exchange-coupled layer systems Fe/FeSn{sub 2}, and Fe/FeSi/Si and the ion-implanted diluted magnetic semiconductor SiC(Fe); Moessbauerspektroskopische Untersuchung von Struktur und Magnetismus der austauschgekoppelten Schichtsysteme Fe/FeSn{sub 2} und Fe/FeSi/Si und des ionenimplantierten verduennten magnetischen Halbleiters SiC(Fe)

    Energy Technology Data Exchange (ETDEWEB)

    Stromberg, Frank

    2009-07-07

    In line with this work the structural and magnetic properties of the exchange coupled layered systems Fe/FeSn{sub 2} and Fe/FeSi/Si and of the Fe ion implanted diluted magnetic semiconductor (DMS) SiC(Fe) were investigated. The main measuring method was the isotope selective {sup 57}Fe conversion electron Moessbauer spectroscopy (CEMS), mostly in connection with the {sup 57}Fe tracer layer technique, in a temperature range from 4.2 K to 340 K. Further measurement techniques were X-ray diffraction (XRD), electron diffraction (LEED, RHEED), SQUID magnetometry and FMR (Ferromagnetic Resonance). In the first part of this work the properties of thin AF FeSn{sub 2}(001) films and of the exchange-bias system Fe/FeSn{sub 2}(001) on InSb(001) were investigated. With the application of {sup 57}Fe-tracer layers and CEMS both the Fe-spin structure and the temperature dependence of the magnetic hyperfine field (B{sub hf}) of FeSn{sub 2} could be examined. The evaporation of Fe films on the FeSn{sub 2} films produced in the latter ones a high perpendicular spin component at the Fe/FeSn{sub 2} interface. In some distance from the interface the Fe spins rotate back into the sample plane. Furthermore {sup 57}Fe-CEMS provided a correlation between the absolute value of the exchange field vertical stroke He vertical stroke and the amount of magnetic defects within the FeSn{sub 2}. Temperature dependent CEMS-measurements yielded informations about the spin dynamics within the AF. The transition temperatures T{sub B}{sup *}, which were interpreted as superparamagnetic blocking temperatures, obtain higher values compared to the temperatures T{sub B} of the exchange-bias effect, obtained with magnetometry measurements. The second part of this work deals with the indirect exchange coupling within Fe/FeSi/Si/FeSi/Fe multilayers and FeSi diffusion barriers. The goal was to achieve Fe free Si interlayers. The CEMS results show that starting from a thickness of t{sub FeSi}=10-12 A of the

  5. Characterizing storm water dispersion and dilution from small coastal streams

    Science.gov (United States)

    Romero, Leonel; Siegel, David A.; McWilliams, James C.; Uchiyama, Yusuke; Jones, Charles

    2016-06-01

    Characterizing the dispersion and dilution of storm water from small coastal creeks is important for understanding the importance of land-derived subsidies to nearby ecosystems and the management of anthropogenic pollutants. In Southern California, creek runoff is episodic, intense, and short-lived while the plumes are buoyant, all of which make the field sampling of freshwater plumes challenging. Numerical modeling offers a viable way to characterize these systems. The dilution and dispersion of freshwater from two creeks that discharge into the Santa Barbara Channel, California is investigated using Regional Ocean Modeling System (ROMS) simulations with a horizontal resolution of 100 m. Tight coupling is found among precipitation, hydrologic discharge, wind forcing, and submesoscale flow structures which all contribute to plume evolution. During flooding, plumes are narrow and attached to the coast, due to downwelling/onshore wind forcing and intense vorticity filaments lying parallel to the shelf. As the storm passes, the winds typically shift to offshore/upwelling favorable conditions and the plume is advected offshore which enhances its dilution. Plumes reach the bottom nearshore while they form thin layers a few meters thick offshore. Dilution field of passive tracers released with the runoff is strongly anisotropic with stronger cross-shelf gradients than along-shelf. Dispersion analysis of statistical moments of the passive tracer distribution results in scale-dependent diffusivities consistent with the particle-pair analysis of Romero et al. Model validation, the roles of submesoscale processes, and wind forcing on plume evolution and application to ecological issues and marine resource management are discussed.

  6. Assessing wastewater dilution in small rivers with high resolution conductivity probes.

    Science.gov (United States)

    Ort, Christoph; Siegrist, Hansruedi

    2009-01-01

    Installation and maintenance of flow gauging stations to assess wastewater dilution in small creeks is expensive. The method outlined in this paper provides a flexible and cheap alternative for situations with dilution factors smaller than 10 and unambiguous flow direction. It is shown that conductivity profiles from three sampling locations enable accurate identification of the dilution factor with an uncertainty of +/-10-30%. Furthermore, much insight can be gained on the temporal behavior of both, the receiving water and the wastewater treatment system by combined analysis of conductivity and temperature data. In this case study the data also enabled identification and tracking down of illegal polluters. PMID:19403973

  7. Solving geometric constraints with genetic simulated annealing algorithm

    Institute of Scientific and Technical Information of China (English)

    刘生礼; 唐敏; 董金祥

    2003-01-01

    This paper applies genetic simulated annealing algorithm (SAGA) to solving geometric constraint problems. This method makes full use of the advantages of SAGA and can handle under-/over- constraint problems naturally. It has advantages (due to its not being sensitive to the initial values) over the Newton-Raphson method, and its yielding of multiple solutions, is an advantage over other optimal methods for multi-solution constraint system. Our experiments have proved the robustness and efficiency of this method.

  8. Adaptive Simulated Annealing Based Protein Loop Modeling of Neurotoxins

    Institute of Scientific and Technical Information of China (English)

    陈杰; 黄丽娜; 彭志红

    2003-01-01

    A loop modeling method, adaptive simulated annealing, for ab initio prediction of protein loop structures, as an optimization problem of searching the global minimum of a given energy function, is proposed. An interface-friendly toolbox-LoopModeller in Windows and Linux systems, VC++ and OpenGL environments is developed for analysis and visualization. Simulation results of three short-chain neurotoxins modeled by LoopModeller show that the method proposed is fast and efficient.

  9. Linking manipulative experiments to field data to test the dilution effect.

    Science.gov (United States)

    Venesky, Matthew D; Liu, Xuan; Sauer, Erin L; Rohr, Jason R

    2014-05-01

    The dilution effect, the hypothesis that biodiversity reduces disease risk, has received support in many systems. However, few dilution effect studies have linked mechanistic experiments to field patterns to establish both causality and ecological relevance. We conducted a series of laboratory experiments and tested the dilution effect hypothesis in an amphibian-Batrachochytrium dendrobatidis (Bd) system and tested for consistency between our laboratory experiments and field patterns of amphibian species richness, host identity and Bd prevalence. In our laboratory experiments, we show that tadpoles can filter feed Bd zoospores and that the degree of suspension feeding was positively associated with their dilution potential. The obligate suspension feeder, Gastrophryne carolinensis, generally diluted the risk of chytridiomycosis for tadpoles of Bufo terrestris and Hyla cinerea, whereas tadpoles of B. terrestris (an obligate benthos feeder) generally amplified infections for the other species. In addition, G. carolinensis reduced Bd abundance on H. cinerea more so in the presence than absence of B. terrestris and B. terrestris amplified Bd abundance on H. cinerea more so in the absence than presence of G. carolinensis. Also, when ignoring species identity, species richness was a significant negative predictor of Bd abundance. In our analysis of field data, the presence of Bufo spp. and Gastrophryne spp. were significant positive and negative predictors of Bd prevalence, respectively, even after controlling for climate, vegetation, anthropogenic factors (human footprint), species richness and sampling effort. These patterns of dilution and amplification supported our laboratory findings, demonstrating that the results are likely ecologically relevant. The results from our laboratory and field data support the dilution effect hypothesis and also suggest that dilution and amplification are predictable based on host traits. Our study is among the first to link

  10. Mean-field analysis of quantum annealing with XX-type terms

    Science.gov (United States)

    Nishimori, Hidetoshi

    I analyze the role of XX-type terms in quantum annealing for a few mean-field systems including the Ising ferromagnet and the Hopfield model, both with many-body interactions. The XX-type terms are shown to be effective to remove first-order quantum phase transitions, which exist in the conventional implementation of quantum annealing using only transverse fields. This means an exponential increase in efficiency, and is suggestive for the design of quantum annealers. I will discuss how and why this phenomenon emerges and what may happen on realistic finite-dimensional lattices.

  11. Effect of Anneal on the Release Behaviour of LY12-Al Alloy

    Institute of Scientific and Technical Information of China (English)

    HU Jian-Bo; YU Yu-Ying; TAN Hua; DAI Cheng-Da

    2006-01-01

    @@ The sound velocities along the release path of annealed LY12-Al are measured by using a velocity interferometer system for any reflector (VISAR) technique. The shear modulus and yield strength are then obtained. Comparison of the experimental results with those of unannealed LY12-Al shows that anneal has little influence on sound velocities and shear modulus though it weakens the yield strength considerably, and changes the dependence of yield strength upon shock stress. The ratio of shear modulus to yield strength of unannealed LY12-Al increases with shock stress monotonically while that of annealed LY12-Al exhibits much more complicated behaviour.

  12. Quantum Annealing of a Disordered Magnet

    OpenAIRE

    Brooke, J.; Bitko, D.; Rosenbaum, T. F.; Aeppli, G.

    2001-01-01

    Traditional simulated annealing utilizes thermal fluctuations for convergence in optimization problems. Quantum tunneling provides a different mechanism for moving between states, with the potential for reduced time scales. We compare thermal and quantum annealing in a model disordered Ising magnet, Li\\sub{Ho}{0.44}\\sub{Y}{0.56}\\sub{F}{4}, where the effects of quantum mechanics can be tuned in the laboratory by varying a magnetic field applied transverse to the Ising axis. Our results indicat...

  13. Adaptive simulated annealing (ASA): Lessons learned

    OpenAIRE

    Ingber, L.

    2000-01-01

    Adaptive simulated annealing (ASA) is a global optimization algorithm based on an associated proof that the parameter space can be sampled much more efficiently than by using other previous simulated annealing algorithms. The author's ASA code has been publicly available for over two years. During this time the author has volunteered to help people via e-mail, and the feedback obtained has been used to further develop the code. Some lessons learned, in particular some which are relevant to ot...

  14. Structural relaxation in annealed hyperquenched basaltic glasses

    DEFF Research Database (Denmark)

    Guo, Xiaoju; Mauro, John C.; Potuzak, M.;

    2012-01-01

    The enthalpy relaxation behavior of hyperquenched (HQ) and annealed hyperquenched (AHQ) basaltic glass is investigated through calorimetric measurements. The results reveal a common onset temperature of the glass transition for all the HQ and AHQ glasses under study, indicating that the primary...... relaxation is activated at the same temperature regardless of the initial departure from equilibrium. The analysis of secondary relaxation at different annealing temperatures provides insights into the enthalpy recovery of HQ glasses....

  15. Irradiation embrittlement and optimisation of annealing

    International Nuclear Information System (INIS)

    This conference is composed of 30 papers grouped in 6 sessions related to the following themes: neutron irradiation effects in pressure vessel steels and weldments used in PWR, WWER and BWR nuclear plants; results from surveillance programmes (irradiation induced damage and annealing processes); studies on the influence of variations in irradiation conditions and mechanisms, and modelling; mitigation of irradiation effects, especially through thermal annealing; mechanical test procedures and specimen size effects

  16. Morphological changes during annealing of polyethylene nanocrystals

    OpenAIRE

    Basu, Nandita; Osichow, Anna; Mecking, Stefan; Reiter, Günter

    2012-01-01

    Polymer crystals are metastable and exhibit morphological changes when being annealed. To observe morphological changes on molecular scales we started from small nanometer-sized crystals of highly folded long-chain polymers. Micron-sized stripes consisting of monolayers or stacks of several layers of flat-on oriented polyethylene nanocrystals were generated via evaporative dewetting from an aqueous dispersion. We followed the morphological changes in time and at progressively higher annealing...

  17. The Effect of SF6 dilution in an Argon plasma

    Science.gov (United States)

    Koirala, Sudip; Gordon, Matt

    2010-02-01

    Plasma etching is widely used in semiconductor industries. There have been extensive studies in the dilution of rare gases; however, limited studies are found in the dilution of electronegative gases. In this work, SF6 content is varied from 5% to 60% in an Ar plasma in a deep reactive ion etching system. A Langmuir probe is used to measure electron temperature (Te), electron density (ne), and electron energy distribution function (eedf). Te decreases monotonically with increasing SF6 at first, and then increases for SF6 content greater than 20%. This increase is attributed to the loss of low energy electrons in attachment and high energy electrons in excitation and ionization. As the content of SF6 is increased above 20%, the dissociation of SF6 increases and most of the low energy electrons are lost in attachment and hence the average electron temperature increases. ne decreases by an order of magnitude as the SF6 dilution is increased from 5% to 60%. eedf shows that the distribution shifts towards high energy with the increase of SF6 content, which is because of the depletion of low energy electrons. )

  18. Influence of alloying and secondary annealing on anneal hardening effect at sintered copper alloys

    Indian Academy of Sciences (India)

    Svetlana Nestorovic

    2005-08-01

    This paper reports results of investigation carried out on sintered copper alloys (Cu, 8 at%; Zn, Ni, Al and Cu–Au with 4 at%Au). The alloys were subjected to cold rolling (30, 50 and 70%) and annealed isochronally up to recrystallization temperature. Changes in hardness and electrical conductivity were followed in order to investigate the anneal hardening effect. This effect was observed after secondary annealing also. Au and Al have been found to be more effective in inducing anneal hardening effect.

  19. First application of quantum annealing to IMRT beamlet intensity optimization

    International Nuclear Information System (INIS)

    Optimization methods are critical to radiation therapy. A new technology, quantum annealing (QA), employs novel hardware and software techniques to address various discrete optimization problems in many fields. We report on the first application of quantum annealing to the process of beamlet intensity optimization for IMRT.We apply recently-developed hardware which natively exploits quantum mechanical effects for improved optimization. The new algorithm, called QA, is most similar to simulated annealing, but relies on natural processes to directly minimize a system’s free energy. A simple quantum system is slowly evolved into a classical system representing the objective function. If the evolution is sufficiently slow, there are probabilistic guarantees that a global minimum will be located.To apply QA to IMRT-type optimization, two prostate cases were considered. A reduced number of beamlets were employed, due to the current QA hardware limitations. The beamlet dose matrices were computed using CERR and an objective function was defined based on typical clinical constraints, including dose-volume objectives, which result in a complex non-convex search space. The objective function was discretized and the QA method was compared to two standard optimization methods, simulated annealing and Tabu search, run on a conventional computing cluster.Based on several runs, the average final objective function value achieved by the QA was 16.9 for the first patient, compared with 10.0 for Tabu and 6.7 for the simulated annealing (SA) method. For the second patient, the values were 70.7 for the QA, 120.0 for Tabu and 22.9 for the SA. The QA algorithm required 27–38% of the time required by the other two methods.In this first application of hardware-enabled QA to IMRT optimization, its performance is comparable to Tabu search, but less effective than the SA in terms of final objective function values. However, its speed was 3–4 times faster than the other two methods

  20. Dilute Oxygen Combustion Phase 2 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, H.M.; Riley, M.F.; Kobayashi, H.

    2005-09-30

    A novel burner, in which fuel (natural gas) and oxidant (oxygen or air) are separately injected into a furnace, shows promise for achieving very low nitrogen oxide(s) (NOx) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NOx through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NOx production. The results of a fundamental and applied research effort on the development of the DOC burner are presented. In addition, the results of a market survey detailing the potential commercial impact of the DOC system are disclosed. The fundamental aspects of the burner development project involved examining the flame characteristics of a natural gas turbulent jet in a high-temperature (~1366 K) oxidant (7-27% O2 vol. wet). Specifically, the mass entrainment rate, the flame lift-off height, the velocity field and major species field of the jet were evaluated as a function of surrounding-gas temperature and composition. The measured entrainment rate of the fuel jet decreased with increasing oxygen content in the surrounding high-temperature oxidant, and was well represented by the d+ scaling correlation found in the literature. The measured flame lift-off height decreased with increasing oxygen content and increasing temperature of the surrounding gas. An increase in surrounding-gas oxygen content and/or temperature inhibited the velocity decay within the jet periphery as a function of axial distance as compared to isothermal turbulent jets. However, the velocity measurements were only broadly represented by the d+ scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW (~0.63 MMBtu/h). The flue gas composition was recorded as a function of furnace nitrogen content, furnace temperature, burner geometric arrangement, firing rate, and fuel injection velocity. NOx emissions

  1. Dilution kicker for the SPS beam dump

    CERN Multimedia

    1974-01-01

    In order to reduce thermal stress on the SPS dump material, the fast-ejected beam was swept horizontally across the dump. This was done with the "dilution kicker" MKDH, still in use at the time of writing. The person on the left is Manfred Mayer. See also 7404072X.

  2. Dilution kicker for the SPS beam dump

    CERN Multimedia

    1974-01-01

    In order to reduce thermal stress on the SPS dump material, the fast-ejected beam was swept horizontally across the dump. This was done with the "dilution kicker" MKDH, still in use at the time of writing. See also 7402051X.

  3. Dry Dilution Refrigerator with High Cooling Power

    Science.gov (United States)

    Uhlig, K.

    2008-03-01

    We present the construction concept and cooling capacity measurements of a 3,4He dilution refrigerator (DR), which was pre-cooled by a commercial pulse tube refrigerator (PTR). No cryogens are needed for the operation of this type of cryostat. The condensation of the helium mash was done in an integrated Joule-Thomson circuit, which was part of the dilution unit. The composition of the dilution unit was standard, but its components (still, heat exchangers, mixing chamber) were designed for high 3He flow. For thermometry, calibrated RuO chip resistance thermometers were available. In order to condense the mixture before an experiment, the fridge was operated like a Joule-Thomson liquefier with a relatively high inlet pressure (4 bar), where the liquid fraction of the circulating 3,4He mixture was accumulated in the dilution unit. The condensation took about 2 hours, and after 2 more hours of running, the temperature of the mixing chamber approached its minimum temperature of 10 mK. The maximum flow rate of the fridge was 1 mmol/s, and the refrigeration capacity of the mixing chamber was 700 μW at 100 mK. High cooling capacity, ease of operation and reliability distinguish this type of milli-Kelvin cooler.

  4. Liquid volumes measurements by isotopic dilution

    International Nuclear Information System (INIS)

    By the nuclear technique, isotopic dilution industrial liquid volumes may be measured in large size recipients of irregular shapes using radiotracers. In the present work laboratory and pilot test are made with 2 radiotracers for optimizing the technique and later done on an industrial scale, obtaining a maximum deviation of +-2%, some recommendations are given to improve the performance of the technique. (author)

  5. LAKE RESTORATION BY DILUTION: MOSES LAKE, WASHINGTON

    Science.gov (United States)

    Dilution water, low in macronutrients, was added to Moses Lake on three occasions in 1977 and once in 1978 during the spring-summer period. The addition resulted in reducing the annual average inflow concentration of phosphorus from about 130-140 micrograms/l to 100 micrograms/l....

  6. Steadiness in Dilute Pyroclastic Density Currents

    Science.gov (United States)

    Andrews, B. J.

    2015-12-01

    Pyroclastic density currents (PDCs) are often unsteady, as evidenced by direct observations of dilute lobes or jets emerging from the fronts of larger currents and by deposits that indicate transient transport and depositional regimes. We used scaled experiments to investigate unsteadiness in dilute PDCs. The experimental currents were run in an 8.5x6.1x2.6 m tank and comprised heated or ambient temperature 20-μm talc powder turbulently suspended in air. Experiments were scaled such that densimetric and thermal Richardson numbers, Froude number, and particle Stokes and settling numbers were dynamically similar to natural dilute PDCs. Although the experiment Reynolds numbers are substantially lower than those of natural PDCs, the experiments are fully turbulent. Experiments were observed with video and high-speed cameras and high-frequency thermocouples. Currents were generated with total eruption durations of 100 s. Unsteadiness in source conditions was produced by interrupting supply for intervals, t, with durations of 1, 2.5, 5, and 10 s in the experimental runs at 35 and 70 s. When t3t>τ, unsteadiness decays such that at a distance of ~4Ut, the currents are again steady. Applied to natural dilute PDCs, our results suggest that currents and their resulting deposits, will only show evidence of unsteadiness if they are disrupted for many seconds and those breaks may "heal" over distances of 100s of meters.

  7. Sulfuric Acid and Water: Paradoxes of Dilution

    Science.gov (United States)

    Leenson, I. A.

    2004-01-01

    On equilibrium properties of aqueous solutions of sulfuric acid, Julius Thomsen has marked that the heat evolved on diluting liquid sulfuric acid with water is a continuous function of the water used, and excluded absolutely the acceptance of definite hydrates as existing in the solution. Information about thermochemical measurement, a discussion…

  8. Diluted magnetic III-V semiconductors

    Science.gov (United States)

    Munekata, H.; Ohno, H.; von Molnar, S.; Segmüller, Armin; Chang, L. L.; Esaki, L.

    1989-10-01

    A new diluted magnetic III-V semiconductor of In1-xMnxAs (xMnAs clusters. Films grown 200 °C, however, are predominantly paramagnetic, and the lattice constant decreases with increasing Mn composition; both are indicative of the formation of a homogeneous alloy. These films have n-type conductivity and reduced band gaps.

  9. PERBANDINGAN KINERJA ALGORITMA GENETIKA DAN SIMULATED ANNEALING UNTUK MASALAH MULTIPLE OBJECTIVE PADA PENJADWALAN FLOWSHOP

    Directory of Open Access Journals (Sweden)

    I Gede Agus Widyadana

    2002-01-01

    Full Text Available The research is focused on comparing Genetics algorithm and Simulated Annealing in the term of performa and processing time. The main purpose is to find out performance both of the algorithm to solve minimizing makespan and total flowtime in a particular flowshop system. Performances of the algorithms are found by simulating problems with variation of jobs and machines combination. The result show the Simulated Annealing is much better than the Genetics up to 90%. The Genetics, however, only had score in processing time, but the trend that plotted suggest that in problems with lots of jobs and lots of machines, the Simulated Annealing will run much faster than the Genetics. Abstract in Bahasa Indonesia : Penelitian ini difokuskan pada pembandingan algoritma Genetika dan Simulated Annealing ditinjau dari aspek performa dan waktu proses. Tujuannya adalah untuk melihat kemampuan dua algoritma tersebut untuk menyelesaikan problem-problem penjadwalan flow shop dengan kriteria minimasi makespan dan total flowtime. Kemampuan kedua algoritma tersebut dilihat dengan melakukan simulasi yang dilakukan pada kombinasi-kombinasi job dan mesin yang berbeda-beda. Hasil simulasi menunjukan algoritma Simulated Annealing lebih unggul dari algoritma Genetika hingga 90%, algoritma Genetika hanya unggul pada waktu proses saja, namun dengan tren waktu proses yang terbentuk, diyakini pada problem dengan kombinasi job dan mesin yang banyak, algoritma Simulated Annealing dapat lebih cepat daripada algoritma Genetika. Kata kunci: Algoritma Genetika, Simulated Annealing, flow shop, makespan, total flowtime.

  10. Influence of annealing temperature on ZnO thin films grown by dual ion beam sputtering

    Indian Academy of Sciences (India)

    Sushil Kumar Pandey; Saurabh Kumar Pandey; Vishnu Awasthi; Ashish Kumar; Uday P Deshpande; Mukul Gupta; Shaibal Mukherjee

    2014-08-01

    We have investigated the influence of in situ annealing on the optical, electrical, structural and morphological properties of ZnO thin films prepared on -type Si(100) substrates by dual ion beam sputtering deposition (DIBSD) system. X-ray diffraction (XRD) measurements showed that all ZnO films have (002) preferred orientation. Full-width at half-maximum (FWHM) of XRD from the (002) crystal plane was observed to reach to a minimum value of 0.139° from ZnO film, annealed at 600 °C. Photoluminescence (PL) measurements demonstrated sharp near-band-edge emission (NBE) at ∼ 380 nm along with broad deep level emissions (DLEs) at room temperature. Moreover, when the annealing temperature was increased from 400 to 600 °C, the ratio of NBE peak intensity to DLE peak intensity initially increased, however, it reduced at further increase in annealing temperature. In electrical characterization as well, when annealing temperature was increased from 400 to 600 °C, room temperature electron mobility enhanced from 6.534 to 13.326 cm2/V s, and then reduced with subsequent increase in temperature. Therefore, 600 °C annealing temperature produced good-quality ZnO film, suitable for optoelectronic devices fabrication. X-ray photoelectron spectroscopy (XPS) study revealed the presence of oxygen interstitials and vacancies point defects in ZnO film annealed at 400 °C.

  11. Microstructural evolution and pitting resistance of annealed lean duplex stainless steel UNS S32304

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Ziying [Department of Materials Science, Fudan University, Shanghai 200433 (China); Key Laboratory of Ecophysics, Department of Physics, Shihezi University, Shihezi 832003 (China); Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters, Yili Normal University, Yining 835000 (China); Han Dong; Jiang Yiming; Shi Chong [Department of Materials Science, Fudan University, Shanghai 200433 (China); Li Jin, E-mail: jinli@fudan.edu.cn [Department of Materials Science, Fudan University, Shanghai 200433 (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer The relationship between pitting corrosion resistance and annealing temperature for UNS S32304 was systemically studied. Black-Right-Pointing-Pointer The specimens annealed at 1080 Degree-Sign C for 1 h, quenched in water exhibit the best pitting corrosion resistance. Black-Right-Pointing-Pointer The relationship between microstructural evolution and pitting resistance of annealed UNS S32304 was discussed in detail. Black-Right-Pointing-Pointer The pitting corrosion resistance is consistent with pitting resistance equivalent number of weaker phase for UNS S32304 alloy. - Abstract: The effect of annealing temperature in the range from 1000 to 1200 Degree-Sign C on the pitting corrosion behavior of duplex stainless steel UNS S32304 was investigated by the potentiodynamic polarization and potentiostatic critical pitting temperature techniques. The microstructural evolution and pit morphologies were studied using a scanning electron microscopy with energy dispersive X-ray spectroscopy. The results demonstrated that the nucleation of metastable pits transformed from austenite phase to ferrite phase with the increasing annealing temperature. As the annealing temperature increased, the pitting corrosion resistance firstly increased and then decreased. The highest pitting corrosion resistance was obtained at 1080 Degree-Sign C with the highest critical pitting temperature value and pitting nucleation resistance. The results could be well explained by the microstructural evolution of ferrite and austenite phases induced by annealing treatment.

  12. Static critical properties of the pure and diluted Heisenberg or Ising models

    OpenAIRE

    Davies, Mathew Raymond.; Stinchcombe, R. B.; Dr. R. B. Stinchcombe

    1982-01-01

    Real space renormalisation group scaling techniques are used to investigate the static critical behaviour of the pure and dilute, classical, anisotropic Heisenberg model. Transfer matrix methods are employed to obtain asymptotically exact expressions for the correlation lengths and susceptibilities of the one-dimensional system. The resulting scaling relationships are combined with an approximate bond moving scheme to treat pure and dilute models in higher dimensionaliti...

  13. Direct observations of the vacancy and its annealing in germanium

    DEFF Research Database (Denmark)

    Slotte, J.; Kilpeläinen, S.; Tuomisto, F.;

    2011-01-01

    K. This is identified as the positron lifetime in a germanium monovacancy. Annealing experiments in the temperature interval 35–300 K reveal two annealing stages. The first at 100 K is tentatively associated with the annealing of the Frenkel pair, the second at 200 K with the annealing of the...

  14. Temperature-dependent permittivity of annealed and unannealed gold films

    CERN Document Server

    Shen, Po-Ting; Lin, Cheng-Wei; Liu, Hsiang-Lin; Chang, Chih-Wei; Chu, Shi-Wei

    2016-01-01

    Due to local field enhancement and subwavelength confinements, nano-plasmonics provide numerous novel applications. Simultaneously, as an efficient nanoscale heat generator from inherent absorption, thermo-plasmonics is emerging as an important branch. However, although significant temperature increase is involved in applications, detailed characterization of metal permittivity at different temperatures is lacking. In this work, we extract the permittivity of gold film from 300K to the annealing temperature of 570K. By comparing annealed and unannealed films, more than one-order difference in thermo-derivative of permittivity is revealed, resulting in unexpectedly large variation of plasmonic properties. Our result is valuable not only for characterizing extensively used unannealed nanoparticles, but also for designing future thermo-nano-plasmonic systems.

  15. Direct Immersion Annealing (DIA) of Block Copolymer Thin Film

    Science.gov (United States)

    Modi, Arvind; Karim, Alamgir

    2014-03-01

    Solvent Vapor Annealing (SVA) methodologies of block copolymer (BCP) films have demonstrated excellent potential for control of nanostructures and morphologies. However, SVA designs require sophisticated instrumentation, and fine control of system parameters in batch processing mode which is relatively complex and limits its feasibility. We developed a faster and robust solvent immersion strategy for microphase separation and nanostructure control of as-cast BCP thin films with minimal sophistication. Our Direct Immersion Annealing (DIA) method requires immersion in a mixture of non-solvent and good solvent (for BCP) for annealing. A non-solvent component prevents dissolution of the film resting on substrate while a good solvent percolates through the film, plasticizes it, and shifts glass-transition below room temperature leading to microphase separation and ordering. Our study of PS-PMMA system demonstrates that a robust control over thin film ordering and transient swelling could be achieved through a fine control of solubility parameter of solvent mixture and temperature with no dead-time. Further, we exhibit the utility of DIA for alignment of BCP domains on topographically patterned substrates. University of Akron Research Foundation (UARF).

  16. Reactor controller design using genetic algorithms with simulated annealing

    International Nuclear Information System (INIS)

    This chapter presents a digital control system for ITU TRIGA Mark-II reactor using genetic algorithms with simulated annealing. The basic principles of genetic algorithms for problem solving are inspired by the mechanism of natural selection. Natural selection is a biological process in which stronger individuals are likely to be winners in a competing environment. Genetic algorithms use a direct analogy of natural evolution. Genetic algorithms are global search techniques for optimisation but they are poor at hill-climbing. Simulated annealing has the ability of probabilistic hill-climbing. Thus, the two techniques are combined here to get a fine-tuned algorithm that yields a faster convergence and a more accurate search by introducing a new mutation operator like simulated annealing or an adaptive cooling schedule. In control system design, there are currently no systematic approaches to choose the controller parameters to obtain the desired performance. The controller parameters are usually determined by test and error with simulation and experimental analysis. Genetic algorithm is used automatically and efficiently searching for a set of controller parameters for better performance. (orig.)

  17. Study of annealing effects in Al–Sb bilayer thin films

    Indian Academy of Sciences (India)

    R K Mangal; B Tripathi; M Singh; Y K Vijay

    2007-02-01

    In this paper, we present preparation and characterization of Al–Sb bilayer thin films. Thin films of thicknesses, 3000/1000 Å and 3000/1500 Å, were obtained by the thermal evaporation (resistive heating) method. Vacuum annealing and rapid thermal annealing methods were used to mix bilayer thin film structure. Results obtained from optical band gap data and Rutherford back scattering spectrometry showed mixing of Al–Sb bilayer system.

  18. Investigation of the impact of annealing on global molecular mobility in glasses: optimization for stabilization of amorphous pharmaceuticals.

    Science.gov (United States)

    Luthra, Suman A; Hodge, Ian M; Pikal, Michael J

    2008-09-01

    The purpose of this research was to investigate the effect of annealing on the molecular mobility in lyophilized glasses using differential scanning calorimetry (DSC) and isothermal microcalorimetry (IMC) techniques. A second objective that emerged was a systematic study of the unusual pre-T(g) thermal events that were observed during DSC warming scans after annealing. Aspartame lyophilized with three different excipients; sucrose, trehalose and poly vinyl pyrrolidone (PVP) was studied. The aim of this work was to quantify the decrease in mobility in amorphous lyophilized aspartame formulations upon systematic postlyophilization annealing. DSC scans of aspartame:sucrose formulation (T(g) = 73 degrees C) showed the presence of a pre-T(g) endotherm which disappeared upon annealing. Aspartame:trehalose (T(g) = 112 degrees C) and aspartame:PVP (T(g) = 100 degrees C) showed a broad exotherm before T(g) and annealing caused appearance of endothermic peaks before T(g). This work also employed IMC to measure the global molecular mobility represented by structural relaxation time (tau(beta)) in both un-annealed and annealed formulations. The effect of annealing on the enthalpy relaxation of lyophilized glasses, as measured by DSC and IMC, was consistent with the behavior predicted using the Tool-Narayanaswamy-Moynihan (TNM) phenomenology (Luthra et al., 2007, in press). The results show that the systems annealed at T(g) -15 degrees C to T(g) -20 degrees C have the lowest molecular mobility. PMID:18200533

  19. Improved AMOLED with aligned poly-Si thin-film transistors by laser annealing and chemical solution treatments

    International Nuclear Information System (INIS)

    Low-temperature polycrystalline silicon (LTPS) thin-film transistors (TFT) were prepared for the active-matrix organic light-emitting displays (AMOLED). The excimer laser annealing (ELA) recrystallization technique was employed with a chemical solution treatment process to improve the TFT characteristic uniformity and the AMOLED display image quality. The characteristics of the poly-Si array thin films were influenced by XeCl ELA optic module design, TFT device channel direction, and laser irradiation overlap ratio. The ELA system module provided aligned poly-Si grain size of 0.3 μm by the homogenization lens design. The chemical solution treatment process included a dilute HF solution (DHF), ozone (O3) water, and buffer oxide etching solution (BOE). The PMOS TFT showed better field effect mobility of 87.6 cm2/V s, and the threshold voltage was -1.35 V. The off current (Ioff) was 1.25x10-11 A, and the on/off current ratio was 6.27x106. In addition, the image quality of the AMOLED display was highly improved using the 2T1C structure design without any compensation circuit.

  20. Improved AMOLED with aligned poly-Si thin-film transistors by laser annealing and chemical solution treatments

    Science.gov (United States)

    Wu, G. M.; Chen, C. N.; Feng, W. S.; Lu, H. C.

    2009-12-01

    Low-temperature polycrystalline silicon (LTPS) thin-film transistors (TFT) were prepared for the active-matrix organic light-emitting displays (AMOLED). The excimer laser annealing (ELA) recrystallization technique was employed with a chemical solution treatment process to improve the TFT characteristic uniformity and the AMOLED display image quality. The characteristics of the poly-Si array thin films were influenced by XeCl ELA optic module design, TFT device channel direction, and laser irradiation overlap ratio. The ELA system module provided aligned poly-Si grain size of 0.3 μm by the homogenization lens design. The chemical solution treatment process included a dilute HF solution (DHF), ozone (O 3) water, and buffer oxide etching solution (BOE). The PMOS TFT showed better field effect mobility of 87.6 cm 2/V s, and the threshold voltage was -1.35 V. The off current ( Ioff) was 1.25×10 -11 A, and the on/off current ratio was 6.27×10 6. In addition, the image quality of the AMOLED display was highly improved using the 2T1C structure design without any compensation circuit.

  1. Improved AMOLED with aligned poly-Si thin-film transistors by laser annealing and chemical solution treatments

    Energy Technology Data Exchange (ETDEWEB)

    Wu, G.M., E-mail: wu@mail.cgu.edu.t [Institute of Electro-Optical Engineering, Department of Electronic Engineering, Department of Chemical and Materials Engineering, Chang Gung University, Taoyuan 333, Taiwan, ROC (China); Chen, C.N.; Feng, W.S.; Lu, H.C. [Institute of Electro-Optical Engineering, Department of Electronic Engineering, Department of Chemical and Materials Engineering, Chang Gung University, Taoyuan 333, Taiwan (China)

    2009-12-15

    Low-temperature polycrystalline silicon (LTPS) thin-film transistors (TFT) were prepared for the active-matrix organic light-emitting displays (AMOLED). The excimer laser annealing (ELA) recrystallization technique was employed with a chemical solution treatment process to improve the TFT characteristic uniformity and the AMOLED display image quality. The characteristics of the poly-Si array thin films were influenced by XeCl ELA optic module design, TFT device channel direction, and laser irradiation overlap ratio. The ELA system module provided aligned poly-Si grain size of 0.3 mum by the homogenization lens design. The chemical solution treatment process included a dilute HF solution (DHF), ozone (O{sub 3}) water, and buffer oxide etching solution (BOE). The PMOS TFT showed better field effect mobility of 87.6 cm{sup 2}/V s, and the threshold voltage was -1.35 V. The off current (I{sub off}) was 1.25x10{sup -11} A, and the on/off current ratio was 6.27x10{sup 6}. In addition, the image quality of the AMOLED display was highly improved using the 2T1C structure design without any compensation circuit.

  2. Post-annealing effect on the room-temperature ferromagnetism in Cu-doped ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yu-Min, E-mail: ymhu@nuk.edu.tw; Kuang, Chein-Hsiun; Han, Tai-Chun; Yu, Chin-Chung [Department of Applied Physics, National University of Kaohsiung, Kaohsiung 811, Taiwan (China); Li, Sih-Sian [Institute of Electro-Optical Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan (China)

    2015-05-07

    In this work, we investigated the structural and magnetic properties of both as-deposited and post-annealed Cu-doped ZnO thin films for better understanding the possible mechanisms of room-temperature ferromagnetism (RT-FM) in ZnO-based diluted magnetic oxides. All of the films have a c-axis-oriented wurtzite structure and display RT-FM. X-ray photoelectron spectroscopy results showed that the incorporated Cu ions in as-deposited films are in 1+ valence state merely, while an additional 2+ valence state occurs in post-annealed films. The presence of Cu{sup 2+} state in post-annealed film accompanies a higher magnetization value than that of as-deposited film and, in particular, the magnetization curves at 10 K and 300 K of the post-annealed film separate distinctly. Since Cu{sup 1+} ion has a filled 3d band, the RT-FM in as-deposited Cu-doped ZnO thin films may stem solely from intrinsic defects, while that in post-annealed films is enhanced due to the presence of CuO crystallites.

  3. U-Mo Plate Blister Anneal Interim Report

    Energy Technology Data Exchange (ETDEWEB)

    Francine J. Rice; Daniel M. Wachs; Adam B. Robinson; Dennis D. Keiser Jr.; Jan-Fong Jue; Danielle M. Perez; Ross Finlay

    2010-10-01

    Blister thresholds in fuel elements have been a longstanding performance parameter for fuel elements of all types. This behavior has yet to be fully defined for the RERTR U-Mo fuel types. Blister anneal studies that began in 2007 have been expanded to include plates from more recent RERTR experiments. Preliminary data presented in this report encompasses the early generations of the U-Mo fuel systems and the most recent but still developing fuel system. Included is an overview of relevant dispersion fuel systems for the purposes of comparison.

  4. U-Mo Plate Blister Anneal Interim Report

    International Nuclear Information System (INIS)

    Blister thresholds in fuel elements have been a longstanding performance parameter for fuel elements of all types. This behavior has yet to be fully defined for the RERTR U-Mo fuel types. Blister anneal studies that began in 2007 have been expanded to include plates from more recent RERTR experiments. Preliminary data presented in this report encompasses the early generations of the U-Mo fuel systems and the most recent but still developing fuel system. Included is an overview of relevant dispersion fuel systems for the purposes of comparison.

  5. 3-D Surface Visualization of pH Titration "Topos": Equivalence Point Cliffs, Dilution Ramps, and Buffer Plateaus

    Science.gov (United States)

    Smith, Garon C.; Hossain, Md Mainul; MacCarthy, Patrick

    2014-01-01

    3-D topographic surfaces ("topos") can be generated to visualize how pH behaves during titration and dilution procedures. The surfaces are constructed by plotting computed pH values above a composition grid with volume of base added in one direction and overall system dilution on the other. What emerge are surface features that…

  6. Origin of reverse annealing effect in hydrogen-implanted silicon

    Energy Technology Data Exchange (ETDEWEB)

    Di, Zengfeng [Los Alamos National Laboratory; Nastasi, Michael A [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory

    2009-01-01

    In contradiction to conventional damage annealing, thermally annealed H-implanted Si exhibits an increase in damage or reverse annealing behavior, whose mechanism has remained elusive. On the basis of quantitative high resolution transmission electron microscopy combined with channeling Rutherford backscattering analysis, we conclusively elucidate that the reverse annealing effect is due to the nucleation and growth of hydrogen-induce platelets. Platelets are responsible for an increase in the height and width the channeling damage peak following increased isochronal anneals.

  7. The annealing robust backpropagation (ARBP) learning algorithm.

    Science.gov (United States)

    Chuang, C C; Su, S F; Hsiao, C C

    2000-01-01

    Multilayer feedforward neural networks are often referred to as universal approximators. Nevertheless, if the used training data are corrupted by large noise, such as outliers, traditional backpropagation learning schemes may not always come up with acceptable performance. Even though various robust learning algorithms have been proposed in the literature, those approaches still suffer from the initialization problem. In those robust learning algorithms, the so-called M-estimator is employed. For the M-estimation type of learning algorithms, the loss function is used to play the role in discriminating against outliers from the majority by degrading the effects of those outliers in learning. However, the loss function used in those algorithms may not correctly discriminate against those outliers. In this paper, the annealing robust backpropagation learning algorithm (ARBP) that adopts the annealing concept into the robust learning algorithms is proposed to deal with the problem of modeling under the existence of outliers. The proposed algorithm has been employed in various examples. Those results all demonstrated the superiority over other robust learning algorithms independent of outliers. In the paper, not only is the annealing concept adopted into the robust learning algorithms but also the annealing schedule k/t was found experimentally to achieve the best performance among other annealing schedules, where k is a constant and is the epoch number. PMID:18249835

  8. Standard Guide for In-Service Annealing of Light-Water Moderated Nuclear Reactor Vessels

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2003-01-01

    1.1 This guide covers the general procedures to be considered for conducting an in-service thermal anneal of a light-water moderated nuclear reactor vessel and demonstrating the effectiveness of the procedure. The purpose of this in-service annealing (heat treatment) is to improve the mechanical properties, especially fracture toughness, of the reactor vessel materials previously degraded by neutron embrittlement. The improvement in mechanical properties generally is assessed using Charpy V-notch impact test results, or alternatively, fracture toughness test results or inferred toughness property changes from tensile, hardness, indentation, or other miniature specimen testing (1). 1.2 This guide is designed to accommodate the variable response of reactor-vessel materials in post-irradiation annealing at various temperatures and different time periods. Certain inherent limiting factors must be considered in developing an annealing procedure. These factors include system-design limitations; physical constrain...

  9. Annealing effect on structural and optical properties of chemical bath deposited MnS thin film

    Science.gov (United States)

    Ulutas, Cemal; Gumus, Cebrail

    2016-03-01

    MnS thin film was prepared by the chemical bath deposition (CBD) method on commercial microscope glass substrate deposited at 30 °C. The as-deposited film was given thermal annealing treatment in air atmosphere at various temperatures (150, 300 and 450 °C) for 1 h. The MnS thin film was characterized by using X-ray diffraction (XRD), UV-vis spectrophotometer and Hall effect measurement system. The effect of annealing temperature on the structural, electrical and optical properties such as optical constants of refractive index (n) and energy band gap (Eg) of the film was determined. XRD measurements reveal that the film is crystallized in the wurtzite phase and changed to tetragonal Mn3O4 phase after being annealed at 300 °C. The energy band gap of film decreased from 3.69 eV to 3.21 eV based on the annealing temperature.

  10. Bond diluted anisotropic quantum Heisenberg model

    International Nuclear Information System (INIS)

    Effects of the bond dilution on the critical temperatures, phase diagrams and the magnetization behaviors of the isotropic and anisotropic quantum Heisenberg model have been investigated in detail. For the isotropic case, bond percolation threshold values have been determined for several numbers of two (2D) and three (3D) dimensional lattices. In order to investigate the effect of the anisotropy in the exchange interaction on the results obtained for the isotropic model, a detailed investigation has been made on a honeycomb lattice. Some interesting results, such as second order reentrant phenomena in the phase diagrams have been found. - Highlights: • Anisotropic quantum Heisenberg model with bond dilution investigated. • Bond percolation threshold values given for 2D and 3D lattices in isotropic case. • Phase diagrams and ground state magnetizations investigated in detail. • Variation of the bond percolation threshold values with anisotropy determined

  11. The linear stability of dilute particulate rings

    CERN Document Server

    Latter, H N; Latter, Henrik N.; Ogilvie, Gordon I.

    2006-01-01

    Irregular structure in planetary rings is often attributed to the intrinsic instabilities of a homogeneous state undergoing Keplerian shear. Previously these have been analysed with simple hydrodynamic models. We instead employ a kinetic theory, in which we solve the linearised moment equations derived in Shu and Stewart 1985 for a dilute ring. This facilitates an examination of velocity anisotropy and non-Newtonian stress, and their effects on the viscous and viscous/gravitational instabilities thought to occur in Saturn's rings. Because we adopt a dilute gas model, the applicability of our results to the actual dense rings of Saturn are significantly curtailled. Nevertheless this study is a necessary preliminary before an attack on the difficult problem of dense ring dynamics. We find the Shu and Stewart formalism admits analytic stability criteria for the viscous overstability, viscous instability, and thermal instability. These criteria are compared with those of a hydrodynamic model incorporating the eff...

  12. Dilute chemical decontamination program. Final report

    International Nuclear Information System (INIS)

    An evaluation of dilute chemical decontamination technology for Boiling Water Reactor (BWRs) was completed under the Dilute Chemical Decontamination Program. An integrated process was developed and demonstrated under simulated BWR decontamination chemical conditions using a 76 cm long section of 15 cm piping removed from an operating BWR. Reasonable process conditions are: 0.012 M oxalic acid and 0.005 M citric acid at pH 3.0 and 900C with a controlled dissolved oxygen concentration of 0.75 ppM. A novel reagent regeneration process using anion-exchange resin preloaded with oxalate and citrate anions was developed to remove the dissolved corrosion products, including Fe(III), from solution during the decontamination. A limited corrosion testing program was completed and no severe adverse effects were identified

  13. Metallic nanowire networks: effects of thermal annealing on electrical resistance

    Science.gov (United States)

    Langley, D. P.; Lagrange, M.; Giusti, G.; Jiménez, C.; Bréchet, Y.; Nguyen, N. D.; Bellet, D.

    2014-10-01

    Metallic nanowire networks have huge potential in devices requiring transparent electrodes. This article describes how the electrical resistance of metal nanowire networks evolve under thermal annealing. Understanding the behavior of such films is crucial for the optimization of transparent electrodes which find many applications. An in-depth investigation of silver nanowire networks under different annealing conditions provides a case study demonstrating that several mechanisms, namely local sintering and desorption of organic residues, are responsible for the reduction of the systems electrical resistance. Optimization of the annealing led to specimens with transmittance of 90% (at 550 nm) and sheet resistance of 9.5 Ω sq-1. Quantized steps in resistance were observed and a model is proposed which provides good agreement with the experimental results. In terms of thermal behavior, we demonstrate that there is a maximum thermal budget that these electrodes can tolerate due to spheroidization of the nanowires. This budget is determined by two main factors: the thermal loading and the wire diameter. This result enables the fabrication and optimization of transparent metal nanowire electrodes for solar cells, organic electronics and flexible displays.

  14. Nuclear techniques of analysis in diamond synthesis and annealing

    Energy Technology Data Exchange (ETDEWEB)

    Jamieson, D. N.; Prawer, S.; Gonon, P.; Walker, R.; Dooley, S.; Bettiol, A.; Pearce, J. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    Nuclear techniques of analysis have played an important role in the study of synthetic and laser annealed diamond. These measurements have mainly used ion beam analysis with a focused MeV ion beam in a nuclear microprobe system. A variety of techniques have been employed. One of the most important is nuclear elastic scattering, sometimes called non-Rutherford scattering, which has been used to accurately characterise diamond films for thickness and composition. This is possible by the use of a database of measured scattering cross sections. Recently, this work has been extended and nuclear elastic scattering cross sections for both natural boron isotopes have been measured. For radiation damaged diamond, a focused laser annealing scheme has been developed which produces near complete regrowth of MeV phosphorus implanted diamonds. In the laser annealed regions, proton induced x-ray emission has been used to show that 50 % of the P atoms occupy lattice sites. This opens the way to produce n-type diamond for microelectronic device applications. All these analytical applications utilize a focused MeV microbeam which is ideally suited for diamond analysis. This presentation reviews these applications, as well as the technology of nuclear techniques of analysis for diamond with a focused beam. 9 refs., 6 figs.

  15. Correlation of annealing with chemical stability in lyophilized pharmaceutical glasses.

    Science.gov (United States)

    Luthra, Suman A; Hodge, Ian M; Utz, Marcel; Pikal, Michael J

    2008-12-01

    This research constitutes a thorough study of the relationship between the chemical stability, aging state and global molecular motion on the one hand, and microscopic local mobility in multi-component systems on the other hand. The objective of the present work was to determine whether annealing a glass below T(g) affects its chemical stability and determine if the rate of chemical degradation couples with global relaxation times determined using calorimetery, and/or with T(1) and T(1rho) relaxation times measured using ssNMR. Model compounds chosen for this research were lyophilized aspartame/sucrose and aspartame/trehalose (1:10 w/w) formulations. The chemical degradation was assessed at various temperatures using high-performance liquid chromatography (HPLC) to determine the impact of annealing on chemical stability. The rate constant for chemical degradation was estimated using stretched time kinetics. The results support the hypothesis that thermal history affects the molecular mobility required for structural relaxation and such effect is critical for chemical stability, that is, a stabilization effect upon annealing is observed. PMID:18481306

  16. Valence Bond Glass Phase in the Diluted Kagome Antiferromagnets

    OpenAIRE

    Singh, R. R. P.

    2010-01-01

    We present a theory for site dilution in the Valence Bond Crystal Phase of the Kagome Lattice Heisenberg Model. The presence of an empty site leads to strong singlet bond across the impurity. It also creates a free spin, which delocalizes inside the unit cell. Finite concentration of quenched impurities leads to a Valence Bond Glass phase. This phase has short-range Valence Bond order, no spin-gap, large spin susceptibilities, linear specific heat due to two-level systems, as well as singlet ...

  17. Destabilization of liquid sheets of dilute emulsions

    OpenAIRE

    Vernay, Clara

    2015-01-01

    One of the major environmental issues related to spraying of pesticides on cultivated crops is the drift phenomenon. Because of the wind, small droplets may drift away from the targeted crop and cause contamination. One way to reduce the drift is to control the spray drop size distribution and reduce the proportion of small drops. In this context, anti-drift additives have been developed, including dilute oil-in-water emulsions. Although being documented, the effects of oil-in-water emulsions...

  18. Bond diluted anisotropic quantum Heisenberg model

    OpenAIRE

    Akıncı, Ümit

    2013-01-01

    Effects of the bond dilution on the critical temperatures, phase diagrams and the magnetization behaviors of the isotropic and anisotropic quantum Heisenberg model have been investigated in detail. For the isotropic case, bond percolation threshold values have been determined for several numbers of two (2D) and three (3D) dimensional lattices. In order to investigate the effect of the anisotropy in the exchange interaction on the results obtained for the isotropic model, a detailed investigat...

  19. Ionic liquids behave as dilute electrolyte solutions

    OpenAIRE

    Gebbie, Matthew A.; Valtiner, Markus; Banquy, Xavier; Fox, Eric T.; Henderson, Wesley A.; Israelachvili, Jacob N.

    2013-01-01

    We combine direct surface force measurements with thermodynamic arguments to demonstrate that pure ionic liquids are expected to behave as dilute weak electrolyte solutions, with typical effective dissociated ion concentrations of less than 0.1% at room temperature. We performed equilibrium force–distance measurements across the common ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C4mim][NTf2]) using a surface forces apparatus with in situ electrochemical contr...

  20. Exchange interaction in diluted magnetic semiconductors

    Czech Academy of Sciences Publication Activity Database

    Sato, K.; Dederichs, P. H.; Katayama-Yoshida, H.; Kudrnovský, Josef

    2004-01-01

    Roč. 16, - (2004), s. S5491-S5497. ISSN 0953-8984 R&D Projects: GA AV ČR IAA1010203 Grant ostatní: RT(XE) RTN1-1999-00145 Institutional research plan: CEZ:AV0Z1010914 Keywords : diluted magnetic semiconductors * Zener p-d excahnge vs superexchange * Curie temperature * mean-field approximation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.049, year: 2004

  1. Isotope dilution strategies for absolute quantitative proteomics

    International Nuclear Information System (INIS)

    The development of mass spectrometry (MS)-based methodologies for high-throughput protein identification has generated a concomitant need for protein quantification. Numerous MS-based relative quantification methodologies have been dedicated to the extensive comparison of multiple proteomes. On the other hand, absolute quantification methodologies, which allow the determination of protein concentrations in biological samples, are generally restricted to defined sets of proteins. Depending on the selected analytical procedure, absolute quantification approaches can provide accurate and precise estimations. These analytical performances are crucial for specific applications such as the evaluation of clinical bio-marker candidates. According to bioanalytical guidelines, accurate analytical processes require internal standards and quality controls. Regarding MS-based analysis of small molecules, isotope dilution has been recognized as the reference method for internal standardization. However, protein quantification methodologies which rely on the isotope dilution principle have been implemented in the proteomic field only recently. In these approaches, the sample is spiked with defined amounts of isotope-labeled analogue(s) of specific proteolytic peptide(s) (AQUA and QconCAT strategies) or protein(s) (PSAQ strategy). In this review, we present a critical overview of these isotope dilution methodologies. (authors)

  2. Dilution physics modeling: Dissolution/precipitation chemistry

    International Nuclear Information System (INIS)

    This report documents progress made to date on integrating dilution/precipitation chemistry and new physical models into the TEMPEST thermal-hydraulics computer code. Implementation of dissolution/precipitation chemistry models is necessary for predicting nonhomogeneous, time-dependent, physical/chemical behavior of tank wastes with and without a variety of possible engineered remediation and mitigation activities. Such behavior includes chemical reactions, gas retention, solids resuspension, solids dissolution and generation, solids settling/rising, and convective motion of physical and chemical species. Thus this model development is important from the standpoint of predicting the consequences of various engineered activities, such as mitigation by dilution, retrieval, or pretreatment, that can affect safe operations. The integration of a dissolution/precipitation chemistry module allows the various phase species concentrations to enter into the physical calculations that affect the TEMPEST hydrodynamic flow calculations. The yield strength model of non-Newtonian sludge correlates yield to a power function of solids concentration. Likewise, shear stress is concentration-dependent, and the dissolution/precipitation chemistry calculations develop the species concentration evolution that produces fluid flow resistance changes. Dilution of waste with pure water, molar concentrations of sodium hydroxide, and other chemical streams can be analyzed for the reactive species changes and hydrodynamic flow characteristics

  3. Atomic displacements in bcc dilute alloys

    Indian Academy of Sciences (India)

    Hitesh Sharma; S Prakash

    2007-04-01

    We present here a systematic investigation of the atomic displacements in bcc transition metal (TM) dilute alloys. We have calculated the atomic displacements in bcc (V, Cr, Fe, Nb, Mo, Ta and W) transition metals (TMs) due to 3d, 4d and 5d TMs at the substitutional site using the Kanzaki lattice static method. Wills and Harrison interatomic potential is used to calculate the atomic force constants, the dynamical matrix and the impurity-induced forces. We have thoroughly investigated the atomic displacements using impurities from 3d, 4d and 5d series in the same host metal and the same impurity in different hosts. We have observed a systematic pattern in the atomic displacements for Cr-, Fe-, Nb-, Mo-, Ta- and W-based dilute alloys. The atomic displacements are found to increase with increase in the number of d electrons for all alloys considered except for V dilute alloys. The 3d impurities are found to be more easily dissolved in the 3d host metals than 4d or 5d TMs whereas 4d and 5d impurities show more solubility in 4d and 5d TMs. In general, the relaxation energy calculation suggests that impurities may be easily solvable in 5d TM hosts when compared to 3d or 4d TMs.

  4. Microstructural tuning of polycrystalline silicon films from hydrogen diluted amorphous silicon films by AIC

    Energy Technology Data Exchange (ETDEWEB)

    Prathap, P.; Tuzun, O.; Roques, S.; Schmitt, S.; Slaoui, A. [InESS, CNRS-UdS, Strasbourg Cedex-2 (France); Maurice, C. [SMS Centre, UMR CNRS 5146, Ecole des Mines de Saint Etienne, 158 Cours Fauriel, 42023 Saint Etienne Cedex 2 (France)

    2011-03-15

    In the present study, the effect of hydrogen dilution in amorphous silicon on its crystallization kinetics and defect distribution using AIC has been studied. The a -Si films were deposited at different ratios of H{sub 2}/(H{sub 2}+SiH{sub 4}) using plasma enhanced chemical vapour deposition (ECR-PECVD) on glass-ceramic substrates. The thicknesses of aluminium and a -Si:H films were 0.20 {mu}m and 0. 37 {mu}m, respectively. The bi-layer structures were annealed in a tube furnace at 475 C for 8 hours in a nitrogen atmosphere. The results indicated that as the hydrogen dilution for a -Si:H films increased from 0% to 85%, the AIC grown poly-Si films were more stressed compressively, while the Raman peak broadened from 6.7 cm{sup -1} to 8.6 cm{sup -1}. It was found that the initiation of crystallization temperature as well as microstructure of poly-Si films was dramatically influenced by the hydrogen content in precursor a -Si films. The distribution of microstructural defects analysed by Electron Back Scattering Diffraction (EBSD) method indicated that frequency of low angle grain boundaries (LAGB) were more at higher hydrogen dilution ratios while coincident site lattice boundaries (CSL) of first order ({sigma}3), second order ({sigma}9) and third order ({sigma}27) were less sensitive to the hydrogen dilutions/content (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Computational multiqubit tunnelling in programmable quantum annealers

    Science.gov (United States)

    Boixo, Sergio; Smelyanskiy, Vadim N.; Shabani, Alireza; Isakov, Sergei V.; Dykman, Mark; Denchev, Vasil S.; Amin, Mohammad H.; Smirnov, Anatoly Yu; Mohseni, Masoud; Neven, Hartmut

    2016-01-01

    Quantum tunnelling is a phenomenon in which a quantum state traverses energy barriers higher than the energy of the state itself. Quantum tunnelling has been hypothesized as an advantageous physical resource for optimization in quantum annealing. However, computational multiqubit tunnelling has not yet been observed, and a theory of co-tunnelling under high- and low-frequency noises is lacking. Here we show that 8-qubit tunnelling plays a computational role in a currently available programmable quantum annealer. We devise a probe for tunnelling, a computational primitive where classical paths are trapped in a false minimum. In support of the design of quantum annealers we develop a nonperturbative theory of open quantum dynamics under realistic noise characteristics. This theory accurately predicts the rate of many-body dissipative quantum tunnelling subject to the polaron effect. Furthermore, we experimentally demonstrate that quantum tunnelling outperforms thermal hopping along classical paths for problems with up to 200 qubits containing the computational primitive.

  6. Hydrogen Annealing Of Single-Crystal Superalloys

    Science.gov (United States)

    Smialek, James L.; Schaeffer, John C.; Murphy, Wendy

    1995-01-01

    Annealing at temperature equal to or greater than 2,200 degrees F in atmosphere of hydrogen found to increase ability of single-crystal superalloys to resist oxidation when subsequently exposed to oxidizing atmospheres at temperatures almost as high. Supperalloys in question are principal constituents of hot-stage airfoils (blades) in aircraft and ground-based turbine engines; also used in other high-temperature applications like chemical-processing plants, coal-gasification plants, petrochemical refineries, and boilers. Hydrogen anneal provides resistance to oxidation without decreasing fatigue strength and without need for coating or reactive sulfur-gettering constituents. In comparison with coating, hydrogen annealing costs less. Benefits extend to stainless steels, nickel/chromium, and nickel-base alloys, subject to same scale-adhesion and oxidation-resistance considerations, except that scale is chromia instead of alumina.

  7. Simulation of Storm Occurrences Using Simulated Annealing.

    Science.gov (United States)

    Lokupitiya, Ravindra S.; Borgman, Leon E.; Anderson-Sprecher, Richard

    2005-11-01

    Modeling storm occurrences has become a vital part of hurricane prediction. In this paper, a method for simulating event occurrences using a simulated annealing algorithm is described. The method is illustrated using annual counts of hurricanes and of tropical storms in the Atlantic Ocean and Gulf of Mexico. Simulations closely match distributional properties, including possible correlations, in the historical data. For hurricanes, traditionally used Poisson and negative binomial processes also predict univariate properties well, but for tropical storms parametric methods are less successful. The authors determined that simulated annealing replicates properties of both series. Simulated annealing can be designed so that simulations mimic historical distributional properties to whatever degree is desired, including occurrence of extreme events and temporal patterning.

  8. Stochastic annealing simulation of cascades in metals

    Energy Technology Data Exchange (ETDEWEB)

    Heinisch, H.L.

    1996-04-01

    The stochastic annealing simulation code ALSOME is used to investigate quantitatively the differential production of mobile vacancy and SIA defects as a function of temperature for isolated 25 KeV cascades in copper generated by MD simulations. The ALSOME code and cascade annealing simulations are described. The annealing simulations indicate that the above Stage V, where the cascade vacancy clusters are unstable,m nearly 80% of the post-quench vacancies escape the cascade volume, while about half of the post-quench SIAs remain in clusters. The results are sensitive to the relative fractions of SIAs that occur in small, highly mobile clusters and large stable clusters, respectively, which may be dependent on the cascade energy.

  9. Magnetic analysis of a melt-spun Fe-dilute Cu60Ag35Fe5 alloy

    International Nuclear Information System (INIS)

    The magnetic properties of a melt-spun Fe-dilute Cu60Ag35Fe5 alloy are examined by X-ray diffraction, magnetic measurements, and transmission electron microscopy (TEM). The X-ray diffraction patterns show that the as-spun and annealed (773 K×36 ks) samples contain Cu and Ag phases and no Fe phases; thus, most Fe atoms are dispersed as clusters. Magnetic measurements indicate that the as-spun and annealed samples exhibit superparamagnetic behavior at 300 K, whereas ferromagnetic and superparamagnetic behaviors coexist at 4.2 K. The magnetic moments of small clusters at 300 K are determined by the nonlinear least squares method as 5148 and 4671 μB for as-spun and annealed samples, respectively, whereas those at 300 K are experimentally determined as 3500 and 3200 μB. This decrease in magnetic moments may imply the formation of anti-ferromagnetic coupling by annealing. TEM observation of the melt-spun sample suggests that there are three regions with different compositions: Cu-rich, Ag-rich, and Fe-rich with no precipitation in the matrix. In addition, these regions have obscure interfaces. The magnetic clusters are attributed to the Fe-rich regions

  10. Infrared luminescence of annealed germanosilicate layers

    International Nuclear Information System (INIS)

    In the light of growing importance of semiconductor nanocrystals for photonics, we report on the growth and characterization of annealed germanosilicate layers used for Ge nanocrystal formation. The films are grown using plasma enhanced chemical vapor deposition (PECVD) and post-annealed in nitrogen at temperatures between 600 and 1200 °C for as long as 2 h. Transmission electron microscopy (TEM), Raman scattering and photoluminescence spectroscopy (PL) has been used to characterize the samples both structurally and optically. Formation of Ge precipitates in the germanosilicate layers have been observed using Raman spectroscopy for a variety of PECVD growth parameters, annealing temperatures and times. Ge–Ge mode at ∼300 cm−1 is clearly observed at temperatures as low as 700 °C for annealing durations for 45 min. Raman results indicate that upon annealing for extended periods of time at temperatures above 900 °C; nanocrystals of few tens of nanometers in diameter inside the oxide matrix and precipitation and interdiffusion of Ge, forming SiGe alloy at the silicon and oxide interface take place. Low temperature PL spectroscopy has been used to observe luminescence from these samples in the vicinity of 1550 nm, an important wavelength for telecommunications. Observed luminescence quenches at 140 K. The photoluminescence data displays three peaks closely interrelated at approximately 1490, 1530 and 1610 nm. PL spectra persist even after removing the oxide layer indicating that the origin of the infrared luminescent centers are not related to the Ge nanocrystals in the oxide layer. -- Highlights: • Nanostructures of Ge formed by precipitation of germanium in PECVD grown germanosilicate films were studied. • We have fabricated SiOx:Ge thin films using PECVD. • Annealing of SiOx:Ge films result in of formation of Ge nanocrystals and SiGe alloy the oxide Si interface. • Low temperature photoluminescence around 1500 nm has been indentified as Ge islands

  11. Infrared luminescence of annealed germanosilicate layers

    Energy Technology Data Exchange (ETDEWEB)

    Tokay, M.S. [Department of Physics, Kırıkkale University, 71450 Kırıkkale (Turkey); Yasar, E., E-mail: erdemyasar@kku.edu.tr [Department of Physics, Kırıkkale University, 71450 Kırıkkale (Turkey); Ağan, S. [Department of Physics, Kırıkkale University, 71450 Kırıkkale (Turkey); Aydınlı, A. [Department of Physics, Bilkent University, 06800 Ankara (Turkey)

    2014-03-15

    In the light of growing importance of semiconductor nanocrystals for photonics, we report on the growth and characterization of annealed germanosilicate layers used for Ge nanocrystal formation. The films are grown using plasma enhanced chemical vapor deposition (PECVD) and post-annealed in nitrogen at temperatures between 600 and 1200 °C for as long as 2 h. Transmission electron microscopy (TEM), Raman scattering and photoluminescence spectroscopy (PL) has been used to characterize the samples both structurally and optically. Formation of Ge precipitates in the germanosilicate layers have been observed using Raman spectroscopy for a variety of PECVD growth parameters, annealing temperatures and times. Ge–Ge mode at ∼300 cm{sup −1} is clearly observed at temperatures as low as 700 °C for annealing durations for 45 min. Raman results indicate that upon annealing for extended periods of time at temperatures above 900 °C; nanocrystals of few tens of nanometers in diameter inside the oxide matrix and precipitation and interdiffusion of Ge, forming SiGe alloy at the silicon and oxide interface take place. Low temperature PL spectroscopy has been used to observe luminescence from these samples in the vicinity of 1550 nm, an important wavelength for telecommunications. Observed luminescence quenches at 140 K. The photoluminescence data displays three peaks closely interrelated at approximately 1490, 1530 and 1610 nm. PL spectra persist even after removing the oxide layer indicating that the origin of the infrared luminescent centers are not related to the Ge nanocrystals in the oxide layer. -- Highlights: • Nanostructures of Ge formed by precipitation of germanium in PECVD grown germanosilicate films were studied. • We have fabricated SiOx:Ge thin films using PECVD. • Annealing of SiOx:Ge films result in of formation of Ge nanocrystals and SiGe alloy the oxide Si interface. • Low temperature photoluminescence around 1500 nm has been indentified as Ge

  12. Quantum annealing correction with minor embedding

    Science.gov (United States)

    Vinci, Walter; Albash, Tameem; Paz-Silva, Gerardo; Hen, Itay; Lidar, Daniel A.

    2015-10-01

    Quantum annealing provides a promising route for the development of quantum optimization devices, but the usefulness of such devices will be limited in part by the range of implementable problems as dictated by hardware constraints. To overcome constraints imposed by restricted connectivity between qubits, a larger set of interactions can be approximated using minor embedding techniques whereby several physical qubits are used to represent a single logical qubit. However, minor embedding introduces new types of errors due to its approximate nature. We introduce and study quantum annealing correction schemes designed to improve the performance of quantum annealers in conjunction with minor embedding, thus leading to a hybrid scheme defined over an encoded graph. We argue that this scheme can be efficiently decoded using an energy minimization technique provided the density of errors does not exceed the per-site percolation threshold of the encoded graph. We test the hybrid scheme using a D-Wave Two processor on problems for which the encoded graph is a two-level grid and the Ising model is known to be NP-hard. The problems we consider are frustrated Ising model problem instances with "planted" (a priori known) solutions. Applied in conjunction with optimized energy penalties and decoding techniques, we find that this approach enables the quantum annealer to solve minor embedded instances with significantly higher success probability than it would without error correction. Our work demonstrates that quantum annealing correction can and should be used to improve the robustness of quantum annealing not only for natively embeddable problems but also when minor embedding is used to extend the connectivity of physical devices.

  13. 2种检测系统测定血、尿淀粉酶高值标本时稀释液的评价与选择%Evaluate and select the dilution for high blood and urine amylase among two measurement system

    Institute of Scientific and Technical Information of China (English)

    周洪; 陈志菊; 周绍英

    2015-01-01

    目的:对湿生化和干生化检测系统测定血、尿淀粉酶高值标本时的稀释液进行评价与选择,期望筛选出与检测系统和标本类型匹配的稀释液。方法纯水、生理盐水(NS)、7%牛血清清蛋白(BSA)、低值血清、低值尿液作为候选稀释液,稀释对应的标本后在湿生化和干生化系统中测定,以卫计委颁布的最新标准分别对偏差和线性进行评价。结果对高值血清标本,同一稀释液在2个系统间的偏差存在较大差异,在湿生化检测系统中,纯水、7% BSA、低值血清作稀释液的偏差均小于行业标准规定的总允许误差(15%),但以低值血清最优;在干生化检测系统中,纯水、NS、低值血清作稀释液的偏差均小于行业标准的规定,以NS最优。对高值尿液标本,在湿生化检测系统中,纯水、低值尿液作稀释液的偏差均小于行业标准规定的总允许误差,以低值尿液最优;在干生化检测系统中,仅低值尿液作稀释液的偏差小于行业标准之规定。线性评价显示,NS不适合作高值血清标本在湿生化检测系统和高值尿液标本在干生化系统的稀释液,7% BSA不适合作高值血清标本在干生化检测系统的稀释液。结论相同稀释液在不同的检测系统中造成的影响不同。高值血清、尿液标本在湿生化检测系统中的最适稀释液分别是低值血清和低值尿液,在干生化检测系统最适稀释液分别是NS和低值尿液。%Objective To evaluate and select the dilution for high blood and urinary amylase among wet chemical & dry chemical de‐tection system ,hope to screen the optimum dilution for different measurement system and specimen type .Methods Pure water (H2 O) ,nor‐mal saline (NS) ,7% bovine serum albumin(7% BSA) ,low amylase specimen of serum and urine selected as candidate dilution .The high amylase specimen was diluted ,then was measured among

  14. Copper ion implanted aluminum nitride dilute magnetic semiconductors (DMS) prepared by molecular beam epitaxy

    International Nuclear Information System (INIS)

    Highlights: • AlN:Cu dilute magnetic semiconductors were successfully prepared by molecular beam epitaxy followed by Cu+ implantation. • Room temperature ferromagnetism was observed after annealing the samples at appropriate temperature. • XRD and Raman spectrometry excluded the possibility of formation of any secondary phases. • By doping intrinsically nonmagnetic dopants (Cu), it has been proved experimentally that their precipitates do not contribute to ferromagnetism. • The reason for ferromagnetism in Cu-doped AlN as observed was explained on the basis of p–d hybridization mechanism (Wu et al.). - Abstract: Diluted magnetic semiconductor (DMS) AlN:Cu films were fabricated by implanting Cu+ ions into AlN thin films at various ion fluxes. AlN films were deposited on c-plane sapphire by molecular beam epitaxy followed by Cu+ ion implantation. The structural and magnetic characterization of the samples was performed through Rutherford backscattering and channeling spectrometry (RBS/C), X-ray diffraction (XRD), Raman spectroscopy, vibrating sample magnetometer (VSM) and SQUID. Incorporation of copper into the AlN lattice was confirmed by RBS, while XRD revealed that no new phase was formed as a result of ion implantation. RBS also indicated formation of defects as a result of implantation process and the depth and degree of damage increased with an increase in ion fluence. Raman spectra showed only E2 (high) and A1 (LO) modes of wurtzite AlN crystal structure and confirmed that no secondary phases were formed. It was found that both Raman modes shift with Cu+ fluences, indicating that Cu ion may go to interstitial or substitutional sites resulting in distortion or damage of lattice. Although as implanted samples showed no magnetization, annealing of the samples resulted in appearance of room temperature ferromagnetism. The saturation magnetization increased with both the annealing temperature as well as with ion fluence. FC/ZFC measurements indicated

  15. Kredsløbsmonitorering med lithium dilution cardiac output-systemet

    DEFF Research Database (Denmark)

    Christiansen, Christian; Hostrup, Anette; Tønnesen, Else;

    2008-01-01

    The lithium dilution cardiac output (LiDCO) system measures cardiac output beat-to-beat with high precision. The system is based on an arterial pulse power analysis which is calibrated every eight hours with a small non-pharmacological dose of lithium. The system is minimally invasive; it requires...

  16. Annealing Increases Stability Of Iridium Thermocouples

    Science.gov (United States)

    Germain, Edward F.; Daryabeigi, Kamran; Alderfer, David W.; Wright, Robert E.; Ahmed, Shaffiq

    1989-01-01

    Metallurgical studies carried out on samples of iridium versus iridium/40-percent rhodium thermocouples in condition received from manufacturer. Metallurgical studies included x-ray, macroscopic, resistance, and metallographic studies. Revealed large amount of internal stress caused by cold-working during manufacturing, and large number of segregations and inhomogeneities. Samples annealed in furnace at temperatures from 1,000 to 2,000 degree C for intervals up to 1 h to study effects of heat treatment. Wire annealed by this procedure found to be ductile.

  17. Transport and stability studies on high band gap a-Si:H films prepared by argon dilution

    Indian Academy of Sciences (India)

    Purabi Gogoi; P N Dixit; Pratima Agarwal

    2008-02-01

    Device quality hydrogenated amorphous silicon films (a-Si:H) are deposited at a high deposition rate (4-5 Å/s) using a mixture of argon and hydrogen-diluted silane. The films exhibit good opto-electronic properties and show less degradation upon light soaking. Light-induced changes in conductivity could be annealed at much lower temperature. The presence of Ar* and atomic hydrogen in plasma replaces the weak Si-Si bonds, which are responsible for light-induced degradation by strong Si-Si bonds. This results in the improved stability of the films.

  18. Preparation of standard mixtures of gas hydrocarbons in air by the diffusion dilution method

    International Nuclear Information System (INIS)

    An original diffusion system able to produce continuously gaseous samples is described. This system can generate samples with concentrations of benzene in air from 0.1 to 1 ppm a reproducible way. The diffusion dilution method used Is also studied. The use of this diffusion system has been extended to the preparation of binary mixtures (benzene-toluene). Whit a secondary dilution device is possible preparing these mixtures over a wide range of concentrations (0.11 to 0.04 ppm for benzene and 0.06 to 0.02 for toluene). (Author) 7 refs

  19. Topologically Ordered Graph Clustering via Deterministic Annealing

    OpenAIRE

    Rossi, Fabrice; Villa-Vialaneix, Nathalie

    2009-01-01

    This paper proposes an organized generalization of Newman and Girvan's modularity measure for graph clustering. Optimized via a deterministic annealing scheme, this measure produces topologically ordered graph partitions that lead to faithful and readable graph representations on a 2 dimensional SOM like planar grid.

  20. Hierarchical Network Design Using Simulated Annealing

    DEFF Research Database (Denmark)

    Thomadsen, Tommy; Clausen, Jens

    2002-01-01

    networks are described and a mathematical model is proposed for a two level version of the hierarchical network problem. The problem is to determine which edges should connect nodes, and how demand is routed in the network. The problem is solved heuristically using simulated annealing which as a sub...

  1. Interference Alignment Using Variational Mean Field Annealing

    DEFF Research Database (Denmark)

    Badiu, Mihai Alin; Guillaud, Maxime; Fleury, Bernard Henri

    2014-01-01

    We study the problem of interference alignment in the multiple-input multiple- output interference channel. Aiming at minimizing the interference leakage power relative to the receiver noise level, we use the deterministic annealing approach to solve the optimization problem. In the corresponding...

  2. Thermal annealing in neutron-irradiated tribromobenzenes

    DEFF Research Database (Denmark)

    Siekierska, K.E.; Halpern, A.; Maddock, A. G.

    1968-01-01

    The distribution of 82Br among various products in neutron-irradiated isomers of tribromobenzene has been investigated, and the effect of thermal annealing examined. Reversed-phase partition chromatography was employed for the determination of radioactive organic products, and atomic bromine in the...

  3. Positron prevacancy effects in pure annealed metals

    International Nuclear Information System (INIS)

    The low-temperature prevacancy effects sometimes observed with positrons in well-annealed high-purity metals are discussed. It is shown that these effects are not experimental artifacts, but are due to trapping of the positrons. It is suggested that dislocations are responsible for these trapping effects. 46 references, 5 figures

  4. Annealing of gold nanostructures sputtered on polytetrafluoroethylene

    Science.gov (United States)

    Siegel, Jakub; Krajcar, Robert; Kolská, Zdeňka; Hnatowicz, Vladimír; Švorčík, Václav

    2011-11-01

    Gold nanolayers sputtered on polytetrafluoroethylene (PTFE) surface and their changes induced by post-deposition annealing at 100°C to 300°C are studied. Changes in surface morphology and roughness are examined by atomic force microscopy, electrical sheet resistance by two point technique, zeta potential by electrokinetic analysis and chemical composition by X-ray photoelectron spectroscopy (XPS) in dependence on the gold layer thickness. Transition from discontinuous to continuous gold coverage takes place at the layer thicknesses 10 to 15 nm and this threshold remains practically unchanged after the annealing at the temperatures below 200°C. The annealing at 300°C, however, leads to significant rearrangement of the gold layer and the transition threshold increases to 70 nm. Significant carbon contamination and the presence of oxidized structures on gold-coated samples are observed in XPS spectra. Gold coating leads to a decrease in the sample surface roughness. Annealing at 300°C of pristine PTFE and gold-coated PTFE results in significant increase of the sample surface roughness.

  5. Annealing Ni nanocrystalline on WC-Co

    International Nuclear Information System (INIS)

    The effects of annealing temperature on nanocrystalline sputter-deposited Ni thin films (500 nm) deposited on WC-Co (4 wt.%) were investigated. Special attention was focused on quantitative evaluation of residual stress and Ni diffusion into the WC-Co, after heat treatment, from 873 to 1273 K. The estimated level of residual stress, as measured by X-ray diffraction, is around -1.3 ± 0.1 GPa for the as-deposited film, whereas after annealing at 1273 K it decreases significantly. Atomic force microscopy shows that high annealing temperature results into an exponential increase of the roughness. An intermixing between the nanocrystalline Ni and the Co from WC substrate occurs, as it is revealed by quantitative depth-resolved Rutherford backscattering spectrometry analysis and also supported by X-ray photoelectron spectroscopy. We ascribe a significant stress relief with the increasing annealing temperature to the diffusion process. The understanding of this process is particularly important in WC-Co parts with the surface treated with Ni in order to improve the maximum surface service temperature.

  6. Annealing Ni nanocrystalline on WC-Co

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, C.M.; Guisbiers, G.; Pereira, S. [CICECO, University of Aveiro, 3810-193 Aveiro (Portugal); Barradas, N.P.; Alves, E. [Nuclear and Technological Institute, E.N. 10, 2686-953 Sacavem (Portugal); Senos, A.M.R., E-mail: anamor@ua.p [CICECO, University of Aveiro, 3810-193 Aveiro (Portugal); Vieira, M.T. [Mechanical Engineering Department, ICEMS, Polo II, 3030-201 Coimbra (Portugal)

    2009-08-12

    The effects of annealing temperature on nanocrystalline sputter-deposited Ni thin films (500 nm) deposited on WC-Co (4 wt.%) were investigated. Special attention was focused on quantitative evaluation of residual stress and Ni diffusion into the WC-Co, after heat treatment, from 873 to 1273 K. The estimated level of residual stress, as measured by X-ray diffraction, is around -1.3 +- 0.1 GPa for the as-deposited film, whereas after annealing at 1273 K it decreases significantly. Atomic force microscopy shows that high annealing temperature results into an exponential increase of the roughness. An intermixing between the nanocrystalline Ni and the Co from WC substrate occurs, as it is revealed by quantitative depth-resolved Rutherford backscattering spectrometry analysis and also supported by X-ray photoelectron spectroscopy. We ascribe a significant stress relief with the increasing annealing temperature to the diffusion process. The understanding of this process is particularly important in WC-Co parts with the surface treated with Ni in order to improve the maximum surface service temperature.

  7. Study of annealing behaviour in GaAs implanted with 70 MeV 120Sn ions by XRD

    International Nuclear Information System (INIS)

    In this study, we have investigated by x-ray diffraction the annealing of damage in GaAs created by 70 MeV 120Sn ion implantation. Annealing has been done isochronally over temperature range up to 600K. A Philips X'Pert system with CuKα1 x-rays of 12 inch beam divergence has been utilized to measure profiles of several Bragg reflections. By introducing an analyzer after the diffraction at the sample w-scans were taken which yielded estimates for the screw dislocation density at different annealing stages. The profiles were simulated at each annealing stage. Also, the variation of sample curvature with annealing temperature was studied. (author)

  8. Quantitative determination of the solidus line in the dilute limit of succinonitrile-camphor alloys

    Science.gov (United States)

    Mota, F. L.; Fabietti, L. M.; Bergeon, N.; Strutzenberg, L. L.; Karma, A.; Billia, B.; Trivedi, R.

    2016-08-01

    Different phase diagram measurements for succinonitrile-camphor alloys to date have yielded different values of the solute partition coefficient and the freezing range of the alloy. These parameters are critical to model solidification microstructure evolution. New measurements are made to precisely characterize the dilute limit of the succinonitrile-camphor phase diagram using thin-sample directional solidification experiments where convection is negligible, so that solute transport in the melt is purely diffusive, and the temperature gradient is constant in time. These results are confirmed through complementary measurements by differential scanning calorimetry and isothermal annealing. Possible measurement uncertainties in previously measured solidus lines are discussed. Experimental results were further confirmed using a boundary layer model of transient planar interface dynamics.

  9. Isochronal recovery and damage rate measurements in electron-irradiated dilute NiGe

    Energy Technology Data Exchange (ETDEWEB)

    Bartels, A.; Weigert, M.; Dworschak, F.

    1987-07-01

    Dilute NiGe alloys were irradiated with 3 MeV electrons below 5 K and subsequently isochronally annealed. In stage II a main recovery stage occurs at 115 K and a smaller one at 150 K both caused by the addition of Ge atoms. Reciprocal damage rates at temperatures immediately above stage I show that single Ge atoms act as stable traps for migrating Ni-selfinterstitials at 73 K. With increasing temperature the trapping radii evaluated from reciprocal damage rates decrease and at temperatures above 115 K trapping of selfinterstitials by Ge atoms cannot be detected any more. The behaviour of the isochronal recovery and of the trapping radii allow us to characterize the 115 K peak as a detrapping stage of interstitials from Ge atoms. Reciprocal damage rates at 73 K performed after pre-irradiation with 3 MeV electrons at high temperatures do not give any indication of a radiation induced segregation of the Ge atoms.

  10. Simultaneous high crystallinity and sub-bandgap optical absorptance in hyperdoped black silicon using nanosecond laser annealing

    Energy Technology Data Exchange (ETDEWEB)

    Franta, Benjamin, E-mail: bafranta@gmail.com; Pastor, David; Gandhi, Hemi H.; Aziz, Michael J.; Mazur, Eric [School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States); Rekemeyer, Paul H.; Gradečak, Silvija [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2015-12-14

    Hyperdoped black silicon fabricated with femtosecond laser irradiation has attracted interest for applications in infrared photodetectors and intermediate band photovoltaics due to its sub-bandgap optical absorptance and light-trapping surface. However, hyperdoped black silicon typically has an amorphous and polyphasic polycrystalline surface that can interfere with carrier transport, electrical rectification, and intermediate band formation. Past studies have used thermal annealing to obtain high crystallinity in hyperdoped black silicon, but thermal annealing causes a deactivation of the sub-bandgap optical absorptance. In this study, nanosecond laser annealing is used to obtain high crystallinity and remove pressure-induced phases in hyperdoped black silicon while maintaining high sub-bandgap optical absorptance and a light-trapping surface morphology. Furthermore, it is shown that nanosecond laser annealing reactivates the sub-bandgap optical absorptance of hyperdoped black silicon after deactivation by thermal annealing. Thermal annealing and nanosecond laser annealing can be combined in sequence to fabricate hyperdoped black silicon that simultaneously shows high crystallinity, high above-bandgap and sub-bandgap absorptance, and a rectifying electrical homojunction. Such nanosecond laser annealing could potentially be applied to non-equilibrium material systems beyond hyperdoped black silicon.

  11. Simultaneous high crystallinity and sub-bandgap optical absorptance in hyperdoped black silicon using nanosecond laser annealing

    International Nuclear Information System (INIS)

    Hyperdoped black silicon fabricated with femtosecond laser irradiation has attracted interest for applications in infrared photodetectors and intermediate band photovoltaics due to its sub-bandgap optical absorptance and light-trapping surface. However, hyperdoped black silicon typically has an amorphous and polyphasic polycrystalline surface that can interfere with carrier transport, electrical rectification, and intermediate band formation. Past studies have used thermal annealing to obtain high crystallinity in hyperdoped black silicon, but thermal annealing causes a deactivation of the sub-bandgap optical absorptance. In this study, nanosecond laser annealing is used to obtain high crystallinity and remove pressure-induced phases in hyperdoped black silicon while maintaining high sub-bandgap optical absorptance and a light-trapping surface morphology. Furthermore, it is shown that nanosecond laser annealing reactivates the sub-bandgap optical absorptance of hyperdoped black silicon after deactivation by thermal annealing. Thermal annealing and nanosecond laser annealing can be combined in sequence to fabricate hyperdoped black silicon that simultaneously shows high crystallinity, high above-bandgap and sub-bandgap absorptance, and a rectifying electrical homojunction. Such nanosecond laser annealing could potentially be applied to non-equilibrium material systems beyond hyperdoped black silicon

  12. Combustion of hythane diluted with CO2

    Directory of Open Access Journals (Sweden)

    Hraiech Ibtissem

    2015-01-01

    Full Text Available With increasing concern about energy shortage and environmental protection, improving engine fuel economy and reducing exhaust emissions have become major research topics in combustion and engine development. Hythane (a blend of hydrogen H2 and natural gas NG has generated a significant interest as an alternative fuel for the future. This paper describes an experimental study of the effects of CO2 addition on the stability of a turbulent jet diffusion NG-H2 flame. The mole fraction of hydrogen (% H2 in NG-H2 mixture was varied from 0% to 50%. The equivalence ratio of the hythane/CO2/air mixture was kept at stoichiometry. The results show that the lift-off height increases with the addition of CO2 at various % H2 content in hythane. However, we observe that with 20% H2, we can obtain a stable flame diluted with 40% CO2, while for 0% H2, the flame is blown out above 20% CO2. This means that the limits of flame blowing out are pushed with the additions of H2. Moreover, the results show that for %H2 content in NG-H2 fuel up to 10%, the addition of CO2 could produce lifted flame if the % CO2 is low. At higher % CO2 dilution, flame would remain attached until blow-out. This is mainly due to the fact that the dilution leads to ejection velocities very high but reactivity of the mixture does not change so the flame tends to stretch.

  13. Magnetopolaron effect in diluted semimagnetic semiconductors

    Science.gov (United States)

    Tarasov, Georgiy G.; Mazur, Yuri I.; Rakitin, Andrey S.; Lavoric, S. R.; Tomm, Jens W.; Hoerstel, W.

    1997-08-01

    Phonon-assisted self-trapping of free carrier is considered in diluted semimagnetics. It is shown that the binding energy of free magnetic polaron can be substantially larger when the 'spin-phonon' coupling is taken into account. For the particular case of 'soft' lattice dynamics the region of stability for hole-induced polaron can be promoted to the temperature of tenths of degrees and magnetic field of a few Tesla. The possible hybridized excitations with the partition of free magnetic polaron are discussed in semimagnetic semiconductors.

  14. Effect of Annealing Ambience on the Chemical Stability of Zr-Si-N Diffusion Barrier

    Institute of Scientific and Technical Information of China (English)

    SONG Zhong-xiao; WANG Yuan; XU Ke-wei; LIU Chun-liang

    2004-01-01

    Zr-Si-N films were deposited by RF magnetron sputtering (MS) technique. A Cu film on the top of Zr-Si-N films was prepared by DC pulsed magnetron sputtering. The Cu/Zr-Si-N systems were annealed in vacuum and N2/H2 gas mixture at 800℃, respectively. The structure of the films were characterized by X-ray diffraction (XRD), Auger electron spectroscopy (AES) and four-point probe method. The sheet resistances of the Cu/Zr-Si-N/Si contact systems annealed in N2/H2 gas mixture were lower than those of the specimens annealed in vacuum at 800℃. The residual oxygen contamination from vacuum annealing ambience influences the sheet resistances of the Cu/Zr-Si-N/Si contact systems due to residual oxygen contamination and/or voids in Cu films. Though thermal stabilities of the Cu/Zr-Si-N/Si systems were maintained up to 800℃ when annealed in vacuum and N2/H2 gas mixture, the changes of thermal stability of specimens were noticeable. The vacuum can accelerate the oxidation and decomposition of Zr-Si-N barrier. On the contrary, N2/H2 gas mixture prevent from the Zr-Si-N barrier oxidation and decomposition.

  15. Effect of Annealing Ambience on the Chemical Stability of Zr-Si-N Diffusion Barrier

    Institute of Scientific and Technical Information of China (English)

    SONGZhong-xiao; WANGYuan; XUKe-wei; LIUChun-liang

    2004-01-01

    Zr-Si-N films were deposited by RF magnetron sputtering (MS) technique. A Cu film on the top of Zr-Si-N films was prepared by DC pulsed magnetron sputtering. The Cu/Zr-Si-N systems were annealed in vacuum and N2/H2 gasmixture at 800℃, respectively. The structure of the films were characterized by X-ray diffraction (XRD), Auger electron spectroscopy (AES) and four-point probe method. The sheet resistances of the Cu/Zr-Si-N/Si contact systems annealed in N2/H2 gas mixture were lower than those of the specimens annealed in vacuum at 800℃. The residual oxygen contamination from vacuum annealing ambience influences the sheet resistances of the Cu/Zr-Si-N/Si contact systems due to residual oxygen contamination and/or voids in Cu films. Though thermal stabilities of the Cu/Zr-Si-N/Si systems were maintained up to 800℃ when annealed in vacuum and N2/H2 gas mixture, the changes of thermal stability of specimens were noticeable. The vacuum can accelerate the oxidation and decomposition of Zr-Si-N barrier. On the contrary, N2/H2 gas mixture prevent from the Zr-Si-N barrier oxidation and decomposition.

  16. Cauchy Annealing Schedule: An Annealing Schedule for Boltzmann Selection Scheme in Evolutionary Algorithms

    OpenAIRE

    Dukkipati, Ambedkar; Murty, Narasimha M; Bhatnagar, Shalabh

    2004-01-01

    Boltzmann selection is an important selection mechanism in evolutionary algorithms as it has theoretical properties which help in theoretical analysis. However, Boltzmann selection is not used in practice because a good annealing schedule for the `inverse temperature' parameter is lacking. In this paper we propose a Cauchy annealing schedule for Boltzmann selection scheme based on a hypothesis that selection-strength should increase as evolutionary process goes on and distance between two sel...

  17. Laser annealing of amorphous silicon core optical fibers

    OpenAIRE

    Healy, N; Mailis, S.; Day, T. D.; Sazio, P.J.A.; Badding, J. V.; A.C. Peacock

    2012-01-01

    Laser annealing of an optical fiber with an amorphous silicon core is demonstrated. The annealing process produces a fiber that has a highly crystalline core, whilst reducing the optical transmission losses by ~3 orders of magnitude.

  18. Hypocoercivity in metastable settings and kinetic simulated annealing

    OpenAIRE

    Monmarché, Pierre

    2015-01-01

    Classical analysis of the simulated annealing algorithm is combined with the more recent hypocoercive method of distorted entropy to prove the convergence for large time of the kinetic Langevin annealing with logarithmic cooling schedule.

  19. Influence of thermal annealing and ion irradiation on zinc silicate phases in nanocomposite ZnO–SiO{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Valiveti, Venkata Siva Kumar, E-mail: vvsk@iuac.res.in; Singh, F.; Ojha, S.; Kanjilal, D.

    2014-10-30

    Highlights: • Nc ZnO–SiOx thin films were grown by rf magnetron sputtering. • Rhombohedral zinc silica phase formed in annealed thin films. • Dilution of zinc silicate phases observed in the irradiated thin films. • Visible PL emission due to defects in ZnO changed with ion fluence. • The results are explained in terms of possible ion beam effects in the material. - Abstract: The formation of zinc silicate phase in nanocomposite (nc) ZnO–SiO{sub x} thin films, its dilution by ion irradiation and subsequent developments were investigated. The nc ZnO–SiO{sub x} thin films used in the study were grown using rf magnetron sputter deposition on silicon (Si) substrates. Thin films were also grown on transmission electron microscopy (TEM) grids in identical conditions. The as-deposited films on Si substrates were annealed at 750 and 900 °C in air for growth of crystalline zinc silicate phase. The as-deposited and 750 °C annealed films were irradiated with 50 MeV oxygen ions in the fluence range from 5 × 10{sup 11} to 1 × 10{sup 14} ions cm{sup −2}. The presence of zinc silicate was observed by X-ray diffraction (XRD) analysis of the annealed films and by Fourier transform infrared (FT-IR) spectroscopy measurements. XRD and FT-IR analyses of the films show increase in zinc silicate phase with annealing and dilution of zinc silicate phase with irradiation. Photoluminescence (PL) analysis of irradiated as-deposited films show change in defects of ZnO. The results are explained in terms of possible ion irradiation induced modifications in the material.

  20. Aplikasi Simulasi Annealing Untuk Menyelesaikan Traveling Salesman Problem

    OpenAIRE

    Larasati, Tuti

    2012-01-01

    Traveling salesman problem is one of combinatorial optimization problems that aim to obtain an optimal solution which determines the route that most minimum. And to resolve and find solutions to these problems one algorithm to be used is simulated annealing. Simulated annealing is an analogy of a liquid metals cooling process called annealing. Annealing is the metallurgical process of heating up a solid and then cooling slowly until it crystallizes. At this final task will shown an analogy an...

  1. Corrosion Behaviour of Annealed Cnx/Tiny Multilayers

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-dong; PAN Chun-xu; FU Qiang; ZHANG Fu-ju; ZOU Yang; ZHANG Shao-hua

    2004-01-01

    The corrosion behaviour of annealed CNx/TiNy multilayers have been investigated using potentiodynamic test in a 0.5MH2SO4 solution. The coating has been deposited on W6Mo5Cr4V2 steel by reactive magnetron sputtering and then annealed at different temperature. The annealed multilayers showed superior corrosion resistance as compared to the as-deposited coating. The corrosion model of annealed CNx/TiNy multilayers has been set up.

  2. Corrosion Behaviour of Annealed Cnx/Tiny Multilayers

    Institute of Scientific and Technical Information of China (English)

    ZHANGGuo-dong; PANChun-xu; FUQiang; ZHANGFu-ju; ZOUYang; ZHANGShao-hua

    2004-01-01

    The corrosion behaviour of annealed CNx/TiNy multilayers have been investigated using potentiodynamic test in a 0.5MH2SO4 solution. The coating has been deposited on W6MoSCr4V2 steel by reactive magnetron sputtering and then annealed at different temperature. The annealed multilayers showed superior corrosion resistance as compared to the as-deposited coating, The corrosion model of annealed CNx/TiNy multilayers has been set up.

  3. Simulated Annealing with Tsallis Weights - A Numerical Comparison

    OpenAIRE

    Hansmann, Ulrich H.E.

    1997-01-01

    We discuss the use of Tsallis generalized mechanics in simulated annealing algorithms. For a small peptide it is shown that older implementations are not more effective than regular simulated annealing in finding ground state configurations. We propose a new implementation which leads to an improvement over regular simulated annealing.

  4. An Effect of Annealing on Shielding Properties of Shungite

    Science.gov (United States)

    Belousova, E. S.; Mahmoud, M. Sh.; Lynkou, L. M.

    2013-05-01

    Annealing of shungite is studied in oxidizing conditions in a chamber with NH4Cl, and in vacuum at 900 °C for 2h. Frequency dependencies of transmission and reflection coefficients of annealed shungite are measured in the frequency range of 8-12 GHz. The minimum reflection at 8-10 GHz was shown for shungite annealed in the oxidizing atmosphere.

  5. Laser beam annealing of heavily damaged implanted layers on silicon

    International Nuclear Information System (INIS)

    The behavior during annealing of heavily doped silicon layers obtained by high current density ion implantation is investigated. The annealing is performed by a laser pulse and the surface layers are studied by Rutherford backscattering, SIMS, ellipsometry and conductivityy measurements. Comparisons with thermal annealing show the advantage of using laser pulses to restore the original cristallinity

  6. Periodic Mg distribution in GaN:{delta}-Mg and the effect of annealing on structural and optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Wegscheider, M. [Institute of Semiconductor/Solid State Physics, Johannes Kepler University of Linz (Austria)], E-mail: Matthias.Wegscheider@jku.at; Simbrunner, C.; Li, Tian [Institute of Semiconductor/Solid State Physics, Johannes Kepler University of Linz (Austria); Jakiela, R. [Institute of Physics, Polish Academy of Sciences, Warsaw (Poland); Navarro-Quezada, A.; Quast, M.; Sitter, H.; Bonanni, A. [Institute of Semiconductor/Solid State Physics, Johannes Kepler University of Linz (Austria)

    2008-11-30

    High p-type conductivity of GaN - commonly achieved via doping with Mg - is a challenge to be faced on the way to the realization of a GaN-based diluted magnetic semiconductor showing ferromagnetism at room temperature. In this work we present a study of GaN:Mg films grown in a metalorganic vapor phase epitaxy process where the Mg atoms are incorporated in a {delta}-doping fashion. The effect of a post-growth annealing step on the diffusivity of magnesium is studied by means of atomic force microscopy and photoluminescence measurements in the ultraviolet regime. A comparison of the presented results with transmission electron microscopy studies leads to the conclusion that a considerable amount of Mg is transported towards the surface where it is thermally removed during the annealing step.

  7. Nonthermal plasma assisted photocatalytic oxidation of dilute benzene

    Indian Academy of Sciences (India)

    J Karuppiah; E Linga Reddy; L Sivachandiran; R Karvembu; Ch Subrahmanyam

    2012-07-01

    Oxidative decomposition of low concentrations (50-1000 ppm) of diluted benzene in air was carried out in a nonthermal plasma (NTP) dielectric barrier discharge (DBD) reactor with the inner electrode made up of stainless steel fibres (SMF) modified with transition metal oxides in such a way to integrate the catalyst in discharge zone. Typical results indicate the better performance of MnO and TiO2/MnO modified systems, which may be attributed to the in situ decomposition of ozone on the surface of MnO that may lead to the formation of atomic oxygen; whereas ultraviolet light induced photocatalytic oxidation may be taking place with TiO2 modified systems. Water vapour improved the selectivity to total oxidation.

  8. Criteria for the evaluation of a dilute decontamination demonstration

    International Nuclear Information System (INIS)

    This document provides the prerequisite technical information required to evaluate and/or develop a project to demonstrate the dilute chemical decontamination of the primary coolant system of light water reactors. The document focuses on five key areas: the basis for establishing programmatic prerequisites and the key decision points that are required for proposal evaluation and/or RFP (Request for Proposal) issuance; a technical review of the state-of-the-art to identify the potential impacts of a reactor's primary-system decontamination on typical BWR and PWR plants; a discussion of the licensing, recertification, fuel warranty, and institutional considerations and processes; a preliminary identification and development of the selection criteria for the reactor and the decontamination process; and a preliminary identification of further research and development that might be required

  9. Criteria for the evaluation of a dilute decontamination demonstration

    Energy Technology Data Exchange (ETDEWEB)

    FitzPatrick, V.F.; Divine, J.R.; Hoenes, G.R.; Munson, L.F.; Card, C.J.

    1981-12-01

    This document provides the prerequisite technical information required to evaluate and/or develop a project to demonstrate the dilute chemical decontamination of the primary coolant system of light water reactors. The document focuses on five key areas: the basis for establishing programmatic prerequisites and the key decision points that are required for proposal evaluation and/or RFP (Request for Proposal) issuance; a technical review of the state-of-the-art to identify the potential impacts of a reactor's primary-system decontamination on typical BWR and PWR plants; a discussion of the licensing, recertification, fuel warranty, and institutional considerations and processes; a preliminary identification and development of the selection criteria for the reactor and the decontamination process; and a preliminary identification of further research and development that might be required.

  10. Homeopathic and high dilution preparations for pest management to tomato crop under organic production system Manejo fitossanitário do tomateiro com uso de preparados homeopáticos e altas diluições sob sistema orgânico de produção

    Directory of Open Access Journals (Sweden)

    Tatiani A Modolon

    2012-03-01

    Full Text Available Tomato crops (Solanum lycopersicum under conventional production system are constantly treated against pest and diseases, with organic synthetic pesticides that are used may cause serious disturbance to environment and human health. This research was carried out in order to study the effect of homeopathic and high dilution preparations on pests and diseases management of tomato crop under organic production system. Two experiments were conducted under field conditions and one in greenhouse. All of them in randomized block design with the cultivar Santa Cruz Kada. The treatments consisted of homeopathic preparations Staphysagria, Arsenicum album, Sulphur, Arnica montana, high dilution preparations of Solanum lycopersicum and Solanum aculeatissimum, at the decimal (DH or centesimal (CH scale of hahnemanian high dilution. Bordeaux mixture, cupric preparation, and Bacillus thuringiensis were also included in weight doses. The preparation Arnica montana 12DH increased the tomato yield under field conditions. The damage incidence of small borer was efficiently reduced with applications of Sulphur 12CH that equalling to B. thuringiensis. The same treatment did not reduce the large borers. B. thuringiensis reduced also the septoria leaf spot incidence in the field. In greenhouse, the high dilution preparation of tomato at 12DH completely suppressed the septoria leaf spot and drastically reduced the same disease at 24DH. The homeopathic and high dilution preparations have the potential to be effective on replacing pesticides that are used on tomato, and could be suitable to fill legal requirement for organic production system.O tomateiro (Solanum lycopersicum sob sistema de produção convencional está constantemente sujeito a pragas e doenças, os pesticidas orgânicos sintéticos que são usados podem causar graves perturbações ao meio ambiente e à saúde humana. O objetivo deste trabalho foi avaliar o efeito de preparados homeopáticos e altas

  11. Globules of annealed amphiphilic copolymers: Surface structure and interactions

    Science.gov (United States)

    Jarkova, E.; Johner, A.; Maresov, E. A.; Semenov, A. N.

    2006-12-01

    A mean-field theory of globules of random amphiphilic copolymers in selective solvents is developed for the case of an annealed copolymer sequence: each unit can be in one of two states, H (insoluble) or P (soluble or less insoluble). The study is focussed on the regime when H and P units tend to form long blocks, and when P units dominate in the dilute phase, but are rare in the globule core. A first-order coil-to-globule transition is predicted at some T = Tcg. The globule core density at the transition point increases as the affinity of P units to the solvent, tildeɛ, is increased. Two collapse transitions, coil → “loose” globule and “loose” globule → “dense” globule, are predicted if tildeɛ is high enough and P units are marginally soluble or weakly insoluble. H and P concentration profiles near the globule surface are obtained and analyzed in detail. It is shown that the surface excess of P units rises as tildeɛ is increased. The surface tension decreases in parallel. Considering the interaction between close enough surfaces of two globules, we show that they always attract each other at a complete equilibrium. It is pointed out, however, that such equilibrium may be difficult to reach, so that partially equilibrium structures (defined by the condition that a chain forming one globule does not penetrate into the core of the other globule) are relevant. It is shown that at such partial equilibrium the interaction is repulsive, so the globules may be stabilized from aggregation. The strongest repulsion is predicted at the coil-to-globule transition point Tcg: the repulsion force decreases with the distance between the surfaces according to a power law. In the general case (apart from Tcg) the force vs. distance decay becomes exponential; the decay length ξ diverges as T → Tcg. The developed theory explains certain anomalous properties observed for globules of amphiphilic homopolymers.

  12. Simulated annealing in orbital flight planning

    Science.gov (United States)

    Soller, Jeffrey

    1990-01-01

    Simulated annealing is used to solve a minimum fuel trajectory problem in the space station environment. The environment is unique because the space station will define the first true multivehicle environment in space. The optimization yields surfaces which are potentially complex, with multiple local minima. Because of the likelihood of these local minima, descent techniques are unable to offer robust solutions. Other deterministic optimization techniques were explored without success. The simulated annealing optimization is capable of identifying a minimum-fuel, two-burn trajectory subject to four constraints. Furthermore, the computational efforts involved in the optimization are such that missions could be planned on board the space station. Potential applications could include the on-site planning of rendezvous with a target craft of the emergency rescue of an astronaut. Future research will include multiwaypoint maneuvers, using a knowledge base to guide the optimization.

  13. Thermal annealing of selected individual quantum dots

    International Nuclear Information System (INIS)

    Cathodoluminescence spectra of single InAs/GaAs quantum dots were recorded before and after consecutive thermal annealing steps. The annealing process leads to an overall blueshift of the spectra indicating In/Ga interdiffusion. Excitonic fine-structure splitting and binding energies of charged and neutral excitonic complexes were monitored. A drastic reduction of the fine-structure splitting from 170 μeV to less than 20 μeV can be observed accompanied by a change of the character of the biexciton from anti-binding to binding with respect to the exciton. Tailoring the fine-structure splitting is especially important for the use of single quantum dots in opto-electronic devices for quantum key distribution where a degeneracy of the exciton ground state (i.e. a fine-structure splitting below the homogeneous linewidth) is required for the on-demand production of entangled photon pairs

  14. Code Generator for Quantum Simulated Annealing

    CERN Document Server

    Tucci, Robert R

    2009-01-01

    This paper introduces QuSAnn v1.2 and Multiplexor Expander v1.2, two Java applications available for free. (Source code included in the distribution.) QuSAnn is a "code generator" for quantum simulated annealing: after the user inputs some parameters, it outputs a quantum circuit for performing simulated annealing on a quantum computer. The quantum circuit implements the algorithm of Wocjan et al. (arXiv:0804.4259), which improves on the original algorithm of Somma et al. (arXiv:0712.1008). The quantum circuit generated by QuSAnn includes some quantum multiplexors. The application Multiplexor Expander allows the user to replace each of those multiplexors by a sequence of more elementary gates such as multiply controlled NOTs and qubit rotations.

  15. Free electron laser annealing of silicon carbide

    International Nuclear Information System (INIS)

    We have studied the application of FEL for the semiconductor processing on the practical device fabrication. FEL annealing at a variety of wavelengths (10.0-13.0 μm) have been performed under room temperature for amorphous silicon carbide (a-SiC) and Nitrogen implanted cubic silicon carbide (3C-SiC) films. Infrared absorption spectroscopy indicated that the annealing at 12.6 μm, corresponding to the absorption peak of Si-C stretch mode, was effective for recrystallization. On the other hand, Hall effect measurements showed the increase of carrier density for N-implanted 3C-SiC films at around 10.4 μm, whereas the absorption was weak at this wavelength. The present results demonstrated that the direct excitation of the lattice vibration with FEL can induce the reconstruction of disordered atoms and activating dopants even at room temperature. (author)

  16. Comparison of Poly-Si Thin Films Prepared by Conventional Furnace Annealing and Pulsed Rapid Thermal Annealing

    Institute of Scientific and Technical Information of China (English)

    JIN Rui-min; ZHENG Xiao-yan; CHEN Lan-li; LUO Peng-hui; GUO Xin-feng; LU Jing-xiao

    2009-01-01

    Amorphous silicon films prepared by PECVD on glass substrate were crystallized by conventional furnace annealing (FA) and rapid thermal annealing ( RTA),respectively. From the Raman spectra and scanning electronic microscope(SEM),it found that the thin films made by RTA had smooth and perfect structure,while the thin films annealed by FA had a higher degree of structural disorder.

  17. EDITORIAL: Focus on Dilute Magnetic Semiconductors FOCUS ON DILUTE MAGNETIC SEMICONDUCTORS

    Science.gov (United States)

    Chambers, Scott A.; Gallagher, Bryan

    2008-05-01

    This focus issue of New Journal of Physics is devoted to the materials science of dilute magnetic semiconductors (DMS). A DMS is traditionally defined as a diamagnetic semiconductor doped with a few to several atomic per cent of some transition metal with unpaired d electrons. Several kinds of dopant-dopant interactions can in principle couple the dopant spins leading to a ferromagnetic ground state in a dilute magnetic system. These include superexchange, which occurs principally in oxides and only between dopants with one intervening oxygen, and double exchange, in which dopants of different formal charges exchange an electron. In both of these mechanisms, the ferromagnetic alignment is not critically dependent on free carriers in the host semiconductor because exchange occurs via bonds. A third mechanism, discovered in the last few years, involves electrons associated with lattice defects that can apparently couple dopant spins. This mechanism is not well understood. Finally, the most desirable mechanism is carrier-mediated exchange interaction in which the dopant spins are coupled by itinerant electrons or holes in the host semiconductor. This mechanism introduces a fundamental link between magnetic and electrical transport properties and offers the possibility of new spintronic functionalities. In particular electrical gate control of ferromagnetism and the use of spin polarized currents to carry signals for analog and digital applications. The spin light emitting diode is a prototypical device of this kind that has been extensively used to characterize the extent of spin polarization in the active light emitting semiconductor heterostructure. The prototypical carrier mediated ferromagnetic DMS is Mn-doped GaAs. This and closely related narrow gap III-V materials have been very extensively studied. Their properties are generally quite well understood and they have led to important insights into fundamental properties of ferromagnetic systems with strong spin

  18. Pyrolytic citrate synthesis and ozone annealing

    International Nuclear Information System (INIS)

    A pyrolytic procedure is described that via a citrate synthesis allowed us to obtain very fine grained YBCO powders that, after a first furnace thermal treatment in ozone, results already to contain a large amount of superconducting microcrystals. A second identical thermal treatment gives a final product strongly textured, as shown by magnetic torque measurements. Complementary structural and diamagnetic measurement show the high quality of these sintered pellets. The role covered by both the pyrolytic preparation and the ozone annealing are discussed

  19. Pyrolitic citrate synthesis and ozone annealing

    International Nuclear Information System (INIS)

    A pyrolytic procedure that via a citrate synthesis allowed to obtain very fine grained YBCO powders that, after a first furnace thermal treatment in ozone, result already to contain a large amount of superconducting microcystals is described. A second identical thermal treatment gives a final product strongly textured, as shown by magnetic torque measurements. Complementary structural and diamagnetic measurements show the high quality of these sintered pellets. The role covered by both the pyrolytic preparation and the ozone annealing are discussed

  20. Using Simulated Annealing to Factor Numbers

    OpenAIRE

    Altschuler, Eric Lewin; Williams, Timothy J.

    2014-01-01

    Almost all public secure communication relies on the inability to factor large numbers. There is no known analytic or classical numeric method to rapidly factor large numbers. Shor[1] has shown that a quantum computer can factor numbers in polynomial time but there is no practical quantum computer that can yet do such computations. We show that a simulated annealing[2] approach can be adapted to find factors of large numbers.

  1. MEDICAL STAFF SCHEDULING USING SIMULATED ANNEALING

    OpenAIRE

    Ladislav Rosocha; Silvia Vernerova; Robert Verner

    2015-01-01

    Purpose: The efficiency of medical staff is a fundamental feature of healthcare facilities quality. Therefore the better implementation of their preferences into the scheduling problem might not only rise the work-life balance of doctors and nurses, but also may result into better patient care. This paper focuses on optimization of medical staff preferences considering the scheduling problem. Methodology/Approach: We propose a medical staff scheduling algorithm based on simulated annealing, a...

  2. MEDICAL STAFF SCHEDULING USING SIMULATED ANNEALING

    OpenAIRE

    Ladislav Rosocha; Silvia Vernerova; Robert Verner

    2015-01-01

    Purpose: The efficiency of medical staff is a fundamental feature of healthcare facilities quality. Therefore the better implementation of their preferences into the scheduling problem might not only rise the work-life balance of doctors and nurses, but also may result into better patient care. This paper focuses on optimization of medical staff preferences considering the scheduling problem.Methodology/Approach: We propose a medical staff scheduling algorithm based on simulated annealing, a ...

  3. Laser-annealing of thin semiconductor films

    OpenAIRE

    Boneberg, Johannes; Nedelcu, Johann; Bucher, Ernst; Leiderer, Paul

    1994-01-01

    Optical reflectivity and transmissivity measurements have been used to investigate the dynamics of melting and recrystallisation of thin films of Si and Ge after laser-annealing with a ns Nd:YAG-laser pulse. We report on temperature dependent changes of the reflectivity of the liquid phase above and below the melting point and on various nucleation and solidification scenarios in thin film, depending on the energy density of the amding laser.

  4. Solving maximum cut problems by simulated annealing

    OpenAIRE

    Myklebust, Tor G. J.

    2015-01-01

    This paper gives a straightforward implementation of simulated annealing for solving maximum cut problems and compares its performance to that of some existing heuristic solvers. The formulation used is classical, dating to a 1989 paper of Johnson, Aragon, McGeoch, and Schevon. This implementation uses no structure peculiar to the maximum cut problem, but its low per-iteration cost allows it to find better solutions than were previously known for 40 of the 89 standard maximum cut instances te...

  5. Thermal annealing of fission fragment radiation damage in CR-39

    International Nuclear Information System (INIS)

    The annealing behavior of fission fragment tracks in CR-39 has been studied at different temperatures for various time intervals. Experimental data, obtained in isothermal and isochronal annealing experiments carried out on CR-39 irradiated with fission fragments of 252Cf, has been analyzed on the basis of different annealing models. It has been attempted to find out the validity of these models, developed on the basis of annealing data in minerals and other detectors, to the annealing data of fission fragment tracks in CR-39

  6. Stored energy and annealing behavior of heavily deformed aluminium

    DEFF Research Database (Denmark)

    Kamikawa, Naoya; Huang, Xiaoxu; Kondo, Yuka;

    2012-01-01

    It has been demonstrated in previous work that a two-step annealing treatment, including a low-temperature, long-time annealing and a subsequent high-temperature annealing, is a promising route to control the microstructure of a heavily deformed metal. In the present study, structural parameters...... 175°C followed by 0.5 h annealing at 200-600°C, where the former treatment leads to discontinuous recrystallization and the latter to uniform structural coarsening. This behavior has been analyzed in terms of the relative change during annealing of energy stored as elastic energy in the dislocation...

  7. Study Of Microstructure And Hardness Of Assab Corrax Steel Annealing

    International Nuclear Information System (INIS)

    Hardness testing and microstructures investigation have been performed at annealed Assab Corrax steel. This preliminary research is gain to look for the high temperature operation resisting materials. The steels were annealed to observe grains and hardness changes in two ways; annealing-temperature constant (400oC) and annealing-time hold constant (4 hours). The results show that the hardness vs. time-hold fluctuates between 200 Hv and 400 Hv, meanwhile it tends to increase due to precipitation hardening by means annealing temperatures. In summary, the hardness is unpredictable by means time-hold and it improves due to precipitation role. The surface micrographs support the phenomena

  8. Reduced-Complexity Deterministic Annealing for Vector Quantizer Design

    Directory of Open Access Journals (Sweden)

    Ortega Antonio

    2005-01-01

    Full Text Available This paper presents a reduced-complexity deterministic annealing (DA approach for vector quantizer (VQ design by using soft information processing with simplified assignment measures. Low-complexity distributions are designed to mimic the Gibbs distribution, where the latter is the optimal distribution used in the standard DA method. These low-complexity distributions are simple enough to facilitate fast computation, but at the same time they can closely approximate the Gibbs distribution to result in near-optimal performance. We have also derived the theoretical performance loss at a given system entropy due to using the simple soft measures instead of the optimal Gibbs measure. We use thederived result to obtain optimal annealing schedules for the simple soft measures that approximate the annealing schedule for the optimal Gibbs distribution. The proposed reduced-complexity DA algorithms have significantly improved the quality of the final codebooks compared to the generalized Lloyd algorithm and standard stochastic relaxation techniques, both with and without the pairwise nearest neighbor (PNN codebook initialization. The proposed algorithms are able to evade the local minima and the results show that they are not sensitive to the choice of the initial codebook. Compared to the standard DA approach, the reduced-complexity DA algorithms can operate over 100 times faster with negligible performance difference. For example, for the design of a 16-dimensional vector quantizer having a rate of 0.4375 bit/sample for Gaussian source, the standard DA algorithm achieved 3.60 dB performance in 16 483 CPU seconds, whereas the reduced-complexity DA algorithm achieved the same performance in 136 CPU seconds. Other than VQ design, the DA techniques are applicable to problems such as classification, clustering, and resource allocation.

  9. Anisotropic pseudopotential for polarized dilute quantum gases

    International Nuclear Information System (INIS)

    An anisotropic pseudopotential arising in the context of collisions of two particles polarized by an external field is rigorously derived and its properties are investigated. Such a low-energy pseudopotential may be useful in describing collective properties of dilute quantum gases, such as molecules polarized by an electric field or metastable 3P2 atoms polarized by a magnetic field. The pseudopotential is expressed in terms of the reactance (K) matrix and derivatives of the Dirac δ function. In most applications, it may be represented as a sum of a traditional spherically symmetric contact term and an anisotropic part. The former contribution may be parametrized by a generalized scattering length. The anisotropic part of the pseudopotential may be characterized by the off-diagonal scattering length for dipolar interactions and off-diagonal scattering volume for quadrupolar interactions. The two-body matrix element of the pseudopotential in a basis of plane waves is also derived

  10. Tunnel backfill erosion by dilute water

    International Nuclear Information System (INIS)

    The goal was to estimate smectite release from tunnel backfill due to dilute groundwater pulse during post glacial conditions. The plan was to apply VTT's two different implementations (BESWD and BESWS) of well-known model of Neretnieks et al. (2009). It appeared difficult to produce repeatable results using this model in COMSOL 4.2 environment, therefore a semi-analytical approximate approach was applied, which enabled to take into account both different geometry and smectite content in tunnel backfill as compared to buffer case. The results are quite similar to buffer results due to the decreasing effect of smaller smectite content and the increasing effect of larger radius. (orig.)

  11. Tunnel backfill erosion by dilute water

    Energy Technology Data Exchange (ETDEWEB)

    Olin, M. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2014-03-15

    The goal was to estimate smectite release from tunnel backfill due to dilute groundwater pulse during post glacial conditions. The plan was to apply VTT's two different implementations (BESW{sub D} and BESW{sub S}) of well-known model of Neretnieks et al. (2009). It appeared difficult to produce repeatable results using this model in COMSOL 4.2 environment, therefore a semi-analytical approximate approach was applied, which enabled to take into account both different geometry and smectite content in tunnel backfill as compared to buffer case. The results are quite similar to buffer results due to the decreasing effect of smaller smectite content and the increasing effect of larger radius. (orig.)

  12. Stable isotope dilution assays in mycotoxin analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rychlik, Michael; Asam, Stefan [Universitaet Muenchen, Lehrstuhl fuer Lebensmittelchemie der Technischen, Garching (Germany)

    2008-01-15

    The principle and applications of stable isotope dilution assays (SIDAs) in mycotoxin analysis are critically reviewed. The general section includes historical aspects of SIDAs, the prerequisites and limitations of the use of stable isotopically labelled internal standards, and possible calibration procedures. In the application section actual SIDAs for the analysis of trichothecenes, zearalenone, fumonisins, patulin, and ochratoxin A are presented. The syntheses and availability of labelled mycotoxins for use as internal standards is reviewed and specific advances in food analysis and toxicology are demonstrated. The review indicates that LC-MS applications, in particular, require the use of stable isotopically labelled standards to compensate for losses during clean-up and for discrimination due to ion suppression. As the commercial availability of these compounds continues to increase, SIDAs can be expected to find expanding use in mycotoxin analysis. (orig.)

  13. Optical processes in dilute nitrides Semiconductors; Alloys

    CERN Document Server

    Potter, R J

    2003-01-01

    This thesis is concerned with the narrow bandgap semiconductor alloys known as dilute nitrides. The initial part of this project was concerned with characterisation of chemical beam epitaxy (CBE) grown samples so that growth techniques could be refined. Early samples show evidence of structural/compositional disorder resulting from the large miscibility gap induced by nitrogen. Non-equilibrium growth was employed to overcome this, eventually resulting in improved material. In the second part of this project, steady-state and time-resolved photoluminescence, along with photomodulated reflectance were employed to investigate the optical properties of molecular beam epitaxy (MBE) grown GalnNAs, GaNAs and InGaAs quantum wells (QWs). Low temperature results show evidence of carrier localization, which was interpreted in terms of structural/compositional fluctuations induced by the nitrogen incorporation. Poor photoluminescence efficiency and rapid decay of emission kinetics indicate the presence of strong non-radi...

  14. Investigation into dilution of zircon suspensions

    International Nuclear Information System (INIS)

    Investigated is the influence of a number of dilution additives in acid as well as in alkali media on the viscosity of utterly destructed structure of zircon suspensions. It is shown that practically all tested additives, except the extracts of fir (0.5 %) and quebracho (0.25-0.5 %), decrease more or less the ultimate stress of the shift and viscosity of utterly destructed structure. It is stated that the usage of complex additive on the basis of syntan-5, triethanolamine and oxalic acid ammonium, in certain ratios provide suspensions of fine-dispersed zircon after washing with polyacrylamide addition, sufficient yield and viscosity in alkali medium. The properties of castings of such suspensions correspond to ones of suspensions with acid media without polyacrilamide usage

  15. Delay of Disorder by Diluted Polymers

    CERN Document Server

    Kityk, A V

    2005-01-01

    We study the effect of diluted flexible polymers on a disordered capillary wave state. The waves are generated at an interface of a dyed water sugar solution and a low viscous silicon oil. This allows for a quantitative measurement of the spatio-temporal Fourier spectrum. The primary pattern after the first bifurcation from the flat interface are squares. With increasing driving strength we observe a melting of the square pattern. It is replaced by a weak turbulent cascade. The addition of a small amount of polymers to the water layer does not affect the critical acceleration but shifts the disorder transition to higher driving strenghs and the short wave length - high frequency fluctuations are suppressed.

  16. Mechanisms of urine concentration and dilution (1961)

    International Nuclear Information System (INIS)

    This paper is devoted to the analysis of a problem in the field of renal physiology which has shown many new developments during the course of the last few years. The following are treated successively: a) the data obtained from measurements of free water clearance and their interpretation; b) the data provided by nephron morphology and the comparative anatomy of the kidney ; c) the data relative to the existence of an intrarenal osmotic gradient; d) the principle of concentration multiplication by a counter current technique; e) the present day theory of counter current concentration of urine, and f) the physiological check on dilution and concentration mechanisms in urine. Lastly, the advantages of the modern theory and the unknown factors which remain are discussed. (authors)

  17. Dilution in a Dense Bottom Jet in Cross Currents

    DEFF Research Database (Denmark)

    Petersen, O.; Larsen, Torben

    1998-01-01

    A 3-dimensional numerical model describing the dilution in the near field around dense vertical jets in a cross flow is formulated and validated against laboratory experiments. The validation shows that the model reproduces the flow pattern well, though the dilution is underestimated by 20%. The ...... model is applied to a case study where the dilution from two vertical jets at an angle in shallow water is described. It is demonstrated that a 20% increase in dilution is possible. It is concluded that the model may become a valuable tool in diffusor design.......A 3-dimensional numerical model describing the dilution in the near field around dense vertical jets in a cross flow is formulated and validated against laboratory experiments. The validation shows that the model reproduces the flow pattern well, though the dilution is underestimated by 20%. The...

  18. The activity of enzymes can be modified by homeopathic dilutions of their effectors

    Directory of Open Access Journals (Sweden)

    Elzbieta Malarczyk

    2012-09-01

    Full Text Available Introduction: The fungal and bacterial materials are very useful for testing the influence of low and very low doses of low molecular phenolic effectors on enzymatic system of phenoloxidases when they are incubated together in the reaction space. Aim: Searching for the model useful biological systems to study the action of diluted low molecular substances on living organisms, which is based on common physical and biochemical analytical procedures. Methods: The fungal and actinomycetal bacterial materials from laboratory cultures as a source of common phenoloxidases, laccase, peroxidase and O-demethylase as well as the pure plant peroxidase were used in experiments described earlier [1-5]. Subsequent dilutions of low molecular phenolic metabolites, appropriate for studied enzymatic systems, prepared in 75% ethanol in the proportion of 1:100 (centesimal and dynamized by shaking in accordance with homeopathic procedures were prepared in our laboratory. During experiments with bacterial and fungal materials and a pure plant peroxidase, which were incubated together with subsequent dilutions of proper phenolic effector, different analytic methods were used including a gel (PAGE [4] and capillary (MEKCE electrophoresis [5], spectral and colorimetric methods [1,2,3] as well as the electron microscopy [5]. Results: In the light of presented data [1-5], the incubation of biological material with diluted phenolic effectors induces various effects on tested enzyme activity. It changed in sinusoidal manner with an gradual growth of dilution rate of tested effectors, which was distinctly visible on the diagram when the number of dilutions was localized on abscissa and biological activity on the ordinate. Exemplary results of the chosen experiments will be presented. For tested enzymes: laccase, peroxidase and O-demethylase, the distance between maximal points of enzymatic activity, shown on a sine curve, repeats more often every 10 subsequent centesimal

  19. Simulated annealing with probabilistic analysis for solving traveling salesman problems

    Science.gov (United States)

    Hong, Pei-Yee; Lim, Yai-Fung; Ramli, Razamin; Khalid, Ruzelan

    2013-09-01

    Simulated Annealing (SA) is a widely used meta-heuristic that was inspired from the annealing process of recrystallization of metals. Therefore, the efficiency of SA is highly affected by the annealing schedule. As a result, in this paper, we presented an empirical work to provide a comparable annealing schedule to solve symmetric traveling salesman problems (TSP). Randomized complete block design is also used in this study. The results show that different parameters do affect the efficiency of SA and thus, we propose the best found annealing schedule based on the Post Hoc test. SA was tested on seven selected benchmarked problems of symmetric TSP with the proposed annealing schedule. The performance of SA was evaluated empirically alongside with benchmark solutions and simple analysis to validate the quality of solutions. Computational results show that the proposed annealing schedule provides a good quality of solution.

  20. Laboratory study to compare the effectiveness of chemical dispersants when applied dilute versus neat

    Energy Technology Data Exchange (ETDEWEB)

    Belore, R.; Ross, S. [S.L. Ross Environmental Research Ltd., Ottawa, ON (Canada)

    2000-07-01

    This study was aimed at comparing the effectiveness of chemical dispersants in neat and dilute form. Two dispersants were selected for this study: Corexit 9500 and Corexit 9527 on Alaska North Slope crude oil. Tests were conducted in the laboratory where the dispersants were applied neat and diluted with salt water. When diluted with salt water in a ratio 1:10, Corexit 9527 did not show a reduction in its effectiveness when used on Alaska North Slope (ANS) crude oil. Corexit 9500, on the other hand, saw its effectiveness on ANS crude oil drastically reduced when diluted with salt water at a ratio 1:10 and 3:10. Since these results are preliminary, the use of diluted Corexit 9500 with salt water in high capacity fire-monitor systems must be carefully considered. Reduced effectiveness of Corexit 9500 could be avoided by using a single-nozzle application in neat form. Further testing was recommended to determine the cause of the reduced efficiency. Some factors to be considered could be the type of oil, method of mixing or delivery of the dispersant, or the contact time between the dispersant and the water carrier. 12 refs., 8 tabs., 5 figs., 1 append.

  1. Dilution in a Dense Bottom Jet in Cross Currents

    DEFF Research Database (Denmark)

    Petersen, O.; Larsen, Torben

    1998-01-01

    A 3-dimensional numerical model describing the dilution in the near field around dense vertical jets in a cross flow is formulated and validated against laboratory experiments. The validation shows that the model reproduces the flow pattern well, though the dilution is underestimated by 20......%. The model is applied to a case study where the dilution from two vertical jets at an angle in shallow water is described. It is demonstrated that a 20% increase in dilution is possible. It is concluded that the model may become a valuable tool in diffusor design....

  2. Ethanol fermentation of a diluted molasses medium by Saccharomyces cerevisiae immobilized on chrysotile

    Directory of Open Access Journals (Sweden)

    Monte Alegre Ranulfo

    2003-01-01

    Full Text Available In this work, the catalytic role of chrysotile support on the acceleration of alcoholic fermentation under non-aseptic conditions by Saccharomyces cerevisiae was investigated. The fermentation medium employed consisted only of diluted sugar-cane molasses. In the batch fermentations process with immobilized yeasts, the initial rate of CO2 production increased roughly 27 % during the first 30 minutes, compared to systems containing no chrysotile. A study of continuous alcoholic fermentation with chrysotile in the reactor bed showed a higher ethanol production rate at the different dilution rates investigated compared to similar fermentations without chrysotile.

  3. Commensurability effects in Nb thin films with randomly diluted pinning arrays

    International Nuclear Information System (INIS)

    We study experimentally the critical depinning current Ic versus applied magnetic field B in Nb thin films, which contain 2D arrays of circular antidots arranged in randomly diluted triangular lattices. For measurements of electric transport close to the Nb transition temperature Tc, the sample temperature is controlled and stabilized via an optical, very low noise heating system. We investigate samples with fixed lattice constant as well as such with fixed antidot-density and compare dilutions between 0% and 80%. Our results show some interesting features in the Ic(B) patterns as commensurability effects at nonmatching fields and a significant suppression of vortex channeling for higher magnetic fields as predicted

  4. The determination of the critical exponent β for dilute magnets by neutron diffraction

    International Nuclear Information System (INIS)

    The critical behaviour of the dilute antiferromagnetic substance (Crsub(x)Alsub(1-x))2O3 is measured by neutron diffraction and the critical exponent β of the magnetization of the sublattices is determined as a function of the concentration ratio. (Crsub(x)Alsub(1-x))2O3 is an Ising system with statistically distributed local magnetic moments. For growing dilution of the magnetic moments and close by the percolation limit a raise of the exponent β is observed. Thus the result supports the theory that the exponent β depends on the concentration. (BHO)

  5. A Tiltable Single-Shot Miniature Dilution Refrigerator for Astrophysical Applications

    CERN Document Server

    Melhuish, Simon J; Piccirillo, Lucio

    2012-01-01

    We present a 3He / 4He dilution refrigerator designed for cooling astronomical mm-wave telescope receivers to around 100 mK. Used in combination with a Gi?fford-McMahon closed-cycle refrigerator, 4He and 3He sorption-pumped refrigerators, our cryogen-free system is capable of achieving 2 microW cooling power at 87 mK. A receiver attached directly to the telescope optics is required to rotate with respect to the downward direction. This scenario, of variable tilt, has proved difficult for typical dilution refrigerators, but our design has a geometry chosen to allow tilt to 45 degrees and beyond.

  6. Prototype Repository. Tracer dilution tests during operation phase, test campaign 3

    Energy Technology Data Exchange (ETDEWEB)

    Harrstroem, Johan; Andersson, Peter (Geosigma AB (Sweden))

    2010-05-15

    The Prototype Repository project is focused on testing and demonstrating the function of the SKB deep repository system. The third tracer dilution campaign during the Prototype Repository operation period was performed in January 2010. The purpose was to estimate the groundwater flows and hydraulic gradients in the boreholes vicinity and will function as a reference for comparison with results from modeling and prior assumptions. The test campaign consisted of tracer dilution tests in 13 different borehole sections. Each test consisted of approximately 15-55 min tracer injection time and about 1-3 days dilution test time depending on the transmissivity of the test section. The data interpretation also included estimates of the local hydraulic gradients in the vicinity of the borehole sections

  7. Prototype Repository. Tracer dilution tests during operation phase, test campaign 3

    International Nuclear Information System (INIS)

    The Prototype Repository project is focused on testing and demonstrating the function of the SKB deep repository system. The third tracer dilution campaign during the Prototype Repository operation period was performed in January 2010. The purpose was to estimate the groundwater flows and hydraulic gradients in the boreholes vicinity and will function as a reference for comparison with results from modeling and prior assumptions. The test campaign consisted of tracer dilution tests in 13 different borehole sections. Each test consisted of approximately 15-55 min tracer injection time and about 1-3 days dilution test time depending on the transmissivity of the test section. The data interpretation also included estimates of the local hydraulic gradients in the vicinity of the borehole sections

  8. A mobile melt-dilute module for the treatment of aluminum research reactor spent fuel

    International Nuclear Information System (INIS)

    A mobile melt-dilute (MMD) module for the treatment of aluminum research reactor spent fuel is being developed jointly by the Savannah River National Laboratory and Argonne National Laboratory. The process utilizes a closed system approach to retain fission products/gases inside a sealed canister after treatment. The MMD process melts and dilutes spent fuel with depleted uranium to obtain an isotopic content of less than 20%. The final ingot is solidified inside the sealed canister and can be stored safely either wet or dry until final disposition or reprocessing. The MMD module can be staged at or near the research reactor fuel storage sites to facilitate the melt-dilute treatment of the spent fuel into a stable non-proliferable form. (author)

  9. High-throughput ab-initio dilute solute diffusion database.

    Science.gov (United States)

    Wu, Henry; Mayeshiba, Tam; Morgan, Dane

    2016-01-01

    We demonstrate automated generation of diffusion databases from high-throughput density functional theory (DFT) calculations. A total of more than 230 dilute solute diffusion systems in Mg, Al, Cu, Ni, Pd, and Pt host lattices have been determined using multi-frequency diffusion models. We apply a correction method for solute diffusion in alloys using experimental and simulated values of host self-diffusivity. We find good agreement with experimental solute diffusion data, obtaining a weighted activation barrier RMS error of 0.176 eV when excluding magnetic solutes in non-magnetic alloys. The compiled database is the largest collection of consistently calculated ab-initio solute diffusion data in the world. PMID:27434308

  10. Elimination of charge carrier trapping in diluted semiconductors

    Science.gov (United States)

    Abbaszadeh, D.; Kunz, A.; Wetzelaer, G. A. H.; Michels, J. J.; Crăciun, N. I.; Koynov, K.; Lieberwirth, I.; Blom, P. W. M.

    2016-06-01

    In 1962, Mark and Helfrich demonstrated that the current in a semiconductor containing traps is reduced by N/Ntr, with N the amount of transport sites, Nt the amount of traps and r a number that depends on the trap energy distribution. For r > 1, the possibility opens that trapping effects can be nearly eliminated when N and Nt are simultaneously reduced. Solution-processed conjugated polymers are an excellent model system to test this hypothesis, because they can be easily diluted by blending them with a high-bandgap semiconductor. We demonstrate that in conjugated polymer blends with 10% active semiconductor and 90% high-bandgap host, the typical strong electron trapping can be effectively eliminated. As a result we were able to fabricate polymer light-emitting diodes with balanced electron and hole transport and reduced non-radiative trap-assisted recombination, leading to a doubling of their efficiency at nearly ten times lower material costs.

  11. Studies of defects and annealing behavior of silicon irradiated with 70 MeV 56Fe ions

    International Nuclear Information System (INIS)

    The effects of 70 MeV irradiation of iron ions in p-type silicon at fluences between 1 x 1012 and 5 x 1014 ions cm-2 were investigated by high resolution X-ray diffraction (HRXRD), electron spin resonance (ESR) and current-voltage measurements. The irradiated samples were isochronally annealed in nitrogen ambient up to 973 K for 2 min using the rapid thermal annealing (RTA) system. The screw dislocation density of the annealed sample (5 x 1014 ions cm-2) estimated at each stage of annealing from the broadening of the HRXRD peak was observed to change from 8.70 x 107 to 1.58 x 107 cm-2 with increasing temperatures. The strain and stress parameters estimated at each stage of annealing using the FWHM of ω-scan clearly indicate relative trend towards the un-irradiated silicon sample. The electron spin resonance studies indicate the presence of the dangling bond state of silicon (Si≡Si) and complex defects. The annealing at 873 K was found to be sufficient for complete removal of the defect centers induced due to irradiation. The I-V studies performed on the irradiated samples before and after annealing indicate that the defects created as a consequence of irradiation trap the charge carriers

  12. The extrinsic hysteresis behavior of dilute binary ferrofluids.

    Science.gov (United States)

    Lin, Lihua; Li, Jian; Lin, Yueqiang; Liu, Xiaodong; Chen, Longlong; Li, Junming; Li, Decai

    2014-10-01

    We report on the magnetization behavior of dilute binary ferrofluids based on γ-Fe(2)O(3)/Ni(2)O(3) composite nanoparticles (A particles), with diameter about 11 nm, and ferrihydrite (Fe(5)O(7)(OH) ・4H2O) nanoparticles (B particles), with diameter about 6 nm. The results show that for the binary ferrofluids with A-particle volume fraction φ(A) = 0.2% and B-particle volume fractions φ(B) = 0.1% and φ(B) = 0.6%, the magnetization curves exhibit quasi-magnetic hysteresis behavior. The demagnetizing curves coincide with the magnetizing curves at high fields. However, for single γ-Fe(2)O(3)/Ni(2)O(3) ferrofluids with φ(A) = 0.2% and binary ferrofluids with φ(A) = 0.2% and φ(B) = 1.0%, the magnetization curves do not behave in this way. Additionally, at high field (750 kA/m), the binary ferrofluid with φ(B) = 1.0% has the smallest magnetization. From the model-of-chain theory, the extrinsic hysteresis behavior of these samples is attributed to the field-induced effects of pre-existing A particle chains, which involve both Brownian rotation of the chains'moments and a Néel rotation of the particles' moments in the chains. The loss of magnetization for the ferrofluids with φ(B) = 1.0% is attributed to pre-existing ring-like A-particle aggregates. These magnetization behaviors of the dilute binary ferrofluids not only depend on features of the strongly magnetic A-particle system, but also modifications of the weaker magnetic B-particle system. PMID:25365919

  13. Debt dilution: when it is a major problem and how to deal with it

    OpenAIRE

    Eyigungor, Burcu

    2013-01-01

    Today we recognize sovereign default, which was once largely confined to developing economies, as a threat not only to investors and to the defaulting country's economic and political stability but also to the global financial system. Burcu Eyigungor explains that a major reason that countries are prone to debt crises is a phenomenon called debt dilution.

  14. Local annealing of complex mechanical devices: a new approach for developing monolithic micro-devices

    Energy Technology Data Exchange (ETDEWEB)

    Bellouard, Y. [Ecole Polytechnique Federale, Lausanne (Switzerland). Inst. de Microtechnique; Lehnert, T.; Bidaux, J.-E. [Departement de Physique (DP), Institut de Genie Atomique (IGA), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Lausanne (Switzerland); Sidler, T. [Departement de Microtechnique (DMT), Institut d' Optique Appliquee (IOA), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Lausanne (Switzerland); Clavel, R. [Departement de Microtechnique (DMT), Institut de Systemes Robotiques (ISR), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Lausanne (Switzerland); Gotthardt, R. [Departement de Physique (DP), Institut de Genie Atomique (IGA), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Lausanne (Switzerland)

    1999-12-15

    The concept of monolithic shape memory alloys (SMA) micro-devices is to integrate all device functions within the same piece of material. This is very interesting in the field of micro-systems, because assembly is avoided. In such devices, the main problem is to create a reversible motion. Recently, the use of the two-way shape memory effect has been investigated. A simpler solution could be to integrate a pullback spring within the monolithic structure. This implies introducing shape memory properties only in some predefined parts of the material. In this paper, an approach based on local annealing of the material is proposed. The annealed parts will exhibit a shape memory effect and the remaining non-annealed parts will have an elastic behavior. Two methods of local annealing have been investigated. The first one is done by an electrical current, which needs a special design of the electrical path. The second one is done by local laser heating, which allows complete freedom in choosing the 'memory regions' of the material. With these tools, complex mechanical devices with active and passive parts can be designed. To illustrate this idea, two mechanical structures containing locally annealed parts are presented. (orig.)

  15. High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films

    Energy Technology Data Exchange (ETDEWEB)

    R. Farrell; V. R. Pagan; A. Kabulski; Sridhar Kuchibhatl; J. Harman; K. R. Kasarla; L. E. Rodak; P. Famouri; J. Peter Hensel; D. Korakakis

    2008-05-01

    A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

  16. Effects of photoassisted O2 annealing on the properties of (Ba,Sr)TiO3 thin films

    International Nuclear Information System (INIS)

    A photoassisted O2 annealing method is proposed to anneal (Ba0.75Sr0.25)TiO3 thin films grown by rf magnetron sputtering. A deuterium lamp, which emits strong ultraviolet and vacuum ultraviolet light, was used as the light source of our photoassisted O2 annealing system. It was found that we could achieve a leakage current density lower than 3x10-8 A/cm2 at 2 V and a dielectric constant, ε, as high as 158.6 by annealing (Ba0.75Sr0.25)TiO3 thin films in this system at 650 deg. C for 2 h

  17. Ion implant rapid thermal anneal international round robin

    Science.gov (United States)

    Yarling, C. B.; Andrew Keenan, W.

    1989-02-01

    The Greater Silicon Valley Implant Users' Group (GSVIUG) has conducted two round robin evaluations to determine the uniformity and repeatability available on commercial rapid thermal processing (RTP) equipment when processing implanted wafers. Twelve RTF vendors have participated, including AET Addax, A.G. Associates, Dainippon Screen, Eaton, Koyo Lindberg, Nanosil, Nichiden Machinery, Peak Systems, Process Products, Tamarack Scientific, Thermco/TEL, and Varian Associates. Sheet resistance contour maps were used to compare sheet resistance, uniformity and repeatability of each vendor. The first round robin was conducted using 100 mm wafers, implanted with high doses (1 × 10 15 and 1 × 10 6 ions/cm 2) of 100 keV boron and arsenic. The time and temperature ( t- T) of the anneal was left to the individual vendors to provide the best repeatability and uniformity for their equipment. The results indicate that excellent repeatability and uniformity are possible using RTP, but no single vendor was superior for all implant conditions. The second round robin was done using 150 mm wafers implanted with 5 × 10 15 ions/cm 2 arsenic at 80 keV. Each vendor was given four wafers to anneal at 1100 °C for 5, 10, 15 and 20 s. Results indicate that each vendor has a characteristic pattern, that much work needs to be done to standardize the t- T measurement, and that the uniformity on 150 mm wafers requires work by some vendors.

  18. Fast assembly of ordered block copolymer nanostructures through microwave annealing.

    Science.gov (United States)

    Zhang, Xiaojiang; Harris, Kenneth D; Wu, Nathanael L Y; Murphy, Jeffrey N; Buriak, Jillian M

    2010-11-23

    Block copolymer self-assembly is an innovative technology capable of patterning technologically relevant substrates with nanoscale precision for a range of applications from integrated circuit fabrication to tissue interfacing, for example. In this article, we demonstrate a microwave-based method of rapidly inducing order in block copolymer structures. The technique involves the usage of a commercial microwave reactor to anneal block copolymer films in the presence of appropriate solvents, and we explore the effect of various parameters over the polymer assembly speed and defect density. The approach is applied to the commonly used poly(styrene)-b-poly(methyl methacrylate) (PS-b-PMMA) and poly(styrene)-b-poly(2-vinylpyridine) (PS-b-P2VP) families of block copolymers, and it is found that the substrate resistivity, solvent environment, and anneal temperature all critically influence the self-assembly process. For selected systems, highly ordered patterns were achieved in less than 3 min. In addition, we establish the compatibility of the technique with directed assembly by graphoepitaxy. PMID:20964379

  19. Dilute Surfactant Methods for Carbonate Formations

    Energy Technology Data Exchange (ETDEWEB)

    Kishore K. Mohanty

    2006-02-01

    There are many fractured carbonate reservoirs in US (and the world) with light oil. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). The process of using dilute anionic surfactants in alkaline solutions has been investigated in this work for oil recovery from fractured oil-wet carbonate reservoirs both experimentally and numerically. This process is a surfactant-aided gravity drainage where surfactant diffuses into the matrix, lowers IFT and contact angle, which decrease capillary pressure and increase oil relative permeability enabling gravity to drain the oil up. Anionic surfactants have been identified which at dilute concentration of 0.05 wt% and optimal salinity can lower the interfacial tension and change the wettability of the calcite surface to intermediate/water-wet condition as well or better than the cationic surfactant DTAB with a West Texas crude oil. The force of adhesion in AFM of oil-wet regions changes after anionic surfactant treatment to values similar to those of water-wet regions. The AFM topography images showed that the oil-wetting material was removed from the surface by the anionic surfactant treatment. Adsorption studies indicate that the extent of adsorption for anionic surfactants on calcite minerals decreases with increase in pH and with decrease in salinity. Surfactant adsorption can be minimized in the presence of Na{sub 2}CO{sub 3}. Laboratory-scale surfactant brine imbibition experiments give high oil recovery (20-42% OOIP in 50 days; up to 60% in 200 days) for initially oil-wet cores through wettability alteration and IFT reduction. Small (<10%) initial gas saturation does not affect significantly the rate of oil recovery in the imbibition process, but larger gas saturation decreases the oil recovery rate. As the core permeability decreases, the rate of oil recovery reduces

  20. Insights into fractal feature evolution from Au/Ge thin films after annealing

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Z.W.; Zhang, S.Y.; Tan, S.; Hou, J.G. [Structure Research Laboratory, University of Science and Technology of China, Hefei, 230026, Anhui (China); Wu, Z.Q. [Fundamental Physics Center, University of Science and Technology of China, Hefei, 230026, Anhui (China)

    2004-03-01

    We report a perplexing behavior of fractal shape transition that results from a change in the annealing temperature and time or the film thickness ratio. We find that a compact-to-open fractal shape transition can be induced by increasing the annealing temperature and time or decreasing the thickness ratio of the Au and Ge films. This behavior is not completely consistent with what is predicted by theories based on diffusion-limited aggregation and previous experimental observations. In this new system, we find that fractal shape transitions are truly dominated by the random-successive nucleation and growth mechanism. (orig.)

  1. Thermal annealing induced structural and optical properties of Se72Te25In3 thin films

    Science.gov (United States)

    Pathak, H. P.; Shukla, Nitesh; Kumar, Vipin; Dwivedi, D. K.

    2016-05-01

    Thin films of a- Se72Te25In3 were prepared by vacuum evaporation technique in a base pressure of 10-6 Torr on to well cleaned glass substrate. a-Se72Te25In3 thin films were annealed at different temperatures below their crystallization temperatures for 2h. The structural analysis of the films has been investigated using X-ray diffraction technique. The optical absorption spectra of these films were measured in the wavelength range 400-1100 nm in order to derive the absorption coefficient of these films. The optical band gap of as prepared and annealed films as a function of photon energy has been studied. It has been found that the optical band gap decreases with increasing annealing temperatures in the present system.

  2. Optimal actuator placement on an active reflector using a modified simulated annealing technique

    Science.gov (United States)

    Kuo, Chin-Po; Bruno, Robin

    1991-01-01

    The development of a lightweight actuation system for maintaining the surface accuracy of a composite honeycomb panel using piezoelectric actuators is discussed. A modified simulated annealing technique is used to optimize the problem with both combinatorial and continuous criteria and with inequality constraints. Near optimal solutions for the location of the actuators, using combinatorial optimization, and for the required actuator forces, employing continuous optimization, are sought by means of the modified simulated annealing technique. The actuator locations are determined by first seeking a near optimum solution using the modified simulated annealing technique. The final actuator configuration consists of an arrangement wherein the piezoelectric actuators are placed along six radial lines. Numerical results showing the achievable surface correction by means of this configuration are presented.

  3. Optimal design of hydraulic manifold blocks based on niching genetic simulated annealing algorithm

    Institute of Scientific and Technical Information of China (English)

    Jia Chunqiang; Yu Ling; Tian Shujun; Gao Yanming

    2007-01-01

    To solve the combinatorial optimization problem of outer layout and inner connection integrated schemes in the design of hydraulic manifold blocks(HMB),a hybrid genetic simulated annealing algorithm based on niche technology is presented.This hybrid algorithm,which combines genetic algorithm,simulated annealing algorithm and niche technology,has a strong capability in global and local search,and all extrema can be found in a short time without strict requests for preferences.For the complex restricted solid spatial layout problems in HMB,the optimizing mathematical model is presented.The key technologies in the integrated layout and connection design of HMB,including the realization of coding,annealing operation and genetic operation,are discussed.The framework of HMB optimal design system based on hybrid optimization strategy is proposed.An example is given to testify the effectiveness and feasibility of the algorithm.

  4. Annealing Behaviour of Helium Bubbles in Titanium Films by Thermal Desorption Spectroscopy and Positron Beam Analysis

    Institute of Scientific and Technical Information of China (English)

    LIU Chao-Zhuo; ZHOU Zhu-Ying; SHI Li-Qun; WANG Bao-Yi; HAO Xiao-Peng; ZHAO Guo-Qing

    2007-01-01

    @@ Helium-containing Ti films are prepared using magnetron sputtering in the helium-argon atmosphere. Isochronal annealing at different temperatures for an hour is employed to reveal the behaviour of helium bubble growth. Ion beam analysis is used to measure the retained helium content. Helium can release largely when annealing above 970 K. A thermal helium desorption spectroscopy system is constructed for assessment of the evolution of helium bubbles in the annealed samples by linear heating (0.4K/s) from room temperature to 1500K. Also, Doppler broadening measurements of positron annihilation radiation spectrum are performed by using changeable energy positron beam. Bubble coarsening evolves gradually below 680K, migration and coalescence of small bubbles dominates in the range of 680-970K, and the Ostwald ripening mechanism enlarges the bubbles with a massive release above 970K.

  5. Study of annealing effects in In–Sb bilayer thin films

    Indian Academy of Sciences (India)

    R K Mangal; Y K Vijay

    2007-04-01

    The thin films of In–Sb having different thicknesses of antimony keeping constant thickness of indium was deposited by thermal evaporation method on ITO coated conducting glass substrates at room temperature and a pressure of 10-5 torr. The samples were annealed for 1 h at 433 K at a pressure of 10-5 torr. The optical transmission spectra of as deposited and annealed films have been carried out at room temperature. The variation in optical band gap with thickness was also observed. Rutherford back scattering and X-ray diffraction analysis confirms mixing of bilayer system. The transverse – characteristic shows mixing effect after annealing at 433 K for 1 h. This study confirms mixing of bilayer structure of semiconductor thin films.

  6. Simulated annealing to handle energy and ancillary services joint management considering electric vehicles

    DEFF Research Database (Denmark)

    Sousa, Tiago M; Soares, Tiago; Morais, Hugo;

    2016-01-01

    The massive use of distributed generation and electric vehicles will lead to a more complex management of the power system, requiring new approaches to be used in the optimal resource scheduling field. Electric vehicles with vehicle-to-grid capability can be useful for the aggregator players in the...... mitigation of renewable sources intermittency and in the ancillary services procurement. In this paper, an energy and ancillary services joint management model is proposed. A simulated annealing approach is used to solve the joint management for the following day, considering the minimization of the...... aggregator total operation costs. The case study considers a distribution network with 33-bus, 66 distributed generation and 2000 electric vehicles. The proposed simulated annealing is matched with a deterministic approach allowing an effective and efficient comparison. The simulated annealing presents a...

  7. Preparation and Luminescence Properties of Y2O3:Eu3+ Nanorods via Post Annealing Process

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Yttrium oxide doped with europium has a great prospective for FED and PDP phosphor application. In present study, the precursor of yttrium oxide hydroxide nitrate nanorod, which was prepared via hydrothermal reaction route using PEG-6000 as template from the starting Y(NO3)3 and KOH reactant system, was used to prepare Y2O3:Eu3+ nanorod via a post annealing process during which the precursor with adjustable shape and size was transformed to final Y2O3:Eu3+ product. XRD, field emission scanning electron microscopy (FE-SEM) and photoluminescence spectra (PL) were used to characterize the crystalline, morphology and luminescence properties of as-formed Y2O3:Eu3+ products synthesized at different post annealing temperatures, respectively. The results indicate that grain morphology of obtained Y2O3:Eu3+ product was nanorod with a mean diameter of about 40~60 nm and length of about 500~700 nm, the nanorod structure and morphology of obtained Y2O3:Eu3+ product maintained during post annealing process and the size varied slightly with different annealing temperatures. Pure cubic Y2O3:Eu3+ phase was formed and the size was the smallest at annealing treatment of 500 ℃. Under the annealing temperature below 500 ℃ its diameter increased with increasing annealing temperature, and remained in a stable size when the annealing temperature was above 500 ℃. The PL spectra of excitation spectra of Y2O3:Eu3+ product show that it exhibits excitation band located at about 395 and 468 nm, respectively. Above two excitation bands could be ascribed to the transition 4f-4f of Eu3+ ions in the Y2O3 host. On the other hand, the main emission peaks of the as-prepared products could be ascribed to the Eu3+ ions transition from 5D0 to 7F2. Furthermore, the luminescent intensity was improved about three times when the annealing temperature increased from 500 to 1000 ℃.

  8. Enhancing performance of amorphous SiGe single junction solar cells by post-deposition thermal annealing

    International Nuclear Information System (INIS)

    In this work, amorphous silicon-germanium (a-SiGe:H) p-i-n single junction solar cells are fabricated using a 40 MHz plasma-enhanced chemical vapor deposition system. Their s-curve characteristics were observed by current density-voltage measurements. Thermal annealing of cells at 150 °C in a vacuum effectively overcame the s-curve behavior. Additionally, comparing the external quantum efficiency spectra of annealed samples with those of as-deposited samples revealed that the spectral response of annealed cells was higher in the long wavelength range (600 ∼ 900 nm). Raman spectroscopy and electrical conductivity analyses revealed that the n-type microcrystalline silicon (n-μc-Si:H) layers of as-deposited cells were not optimal. Experimental results indicate that the i/n barrier heights of the as-deposited and annealed samples were 0.31 eV and 0.20 eV , respectively. The high energy barrier implies that the bad collection ability of charge carriers near the i/n interfaces of solar cells. An energy conversion efficiency of 6.38% was achieved after post-deposition annealing. The improvement in efficiency is concluded to have been caused largely by retention of n-μc-Si:H layers of high crystallinity and electrical conductivity after annealing. - Highlights: ► Demonstration of thermal annealing in overcoming the s-curve behavior. ► Annealing treatments lead to better n-type microcrystalline silicon thin films. ► Energy conversion efficiency of 6.38% was achieved after post-deposition annealing

  9. Effect of RF power and annealing on chemical bonding and morphology of a-CNx thin films as humidity sensor

    International Nuclear Information System (INIS)

    Amorphous carbon nitride (a-CNx) thin films were deposited using radio frequency plasma enhanced chemical vapor deposition (rf-PECVD) technique. A set of a-CNx thin films were prepared using pure methane (CH4) gas diluted with nitrogen (N2) gas. The rf power was varied at 50, 60, 70, 80, 90 and 100 W. These films were then annealed at 400 °C in a quartz tube furnace in argon (Ar) gas. The effects of rf power and thermal annealing on the chemical bonding and morphology of these samples were studied. Surface profilometer was used to measure film thickness. Fourier transform infra-red spectroscopy (FTIR) and Field emission scanning electron microscopy (FESEM) measurements were used to determine their chemical bonding and morphology respectively. The deposition rate of the films increased constantly with increasing rf power up to 80W, before decreasing with further increase in rf power. Fourier transform infra-red spectroscopy (FTIR) studies showed a systematic change in the spectra and revealed three main peaks included C-N, C=N, C=C and C≡N triple bond. C=N and C≡N bonds decreased with increased C-N bonds after thermal annealing process. The FESEM images showed that the structure is porous for as-deposited and covered by granule-like grain structure after thermal annealing process was done. The resistance of the a-CNx thin film changed from 23.765 kΩ to 5.845 kΩ in the relative humidity range of 5 to 92 % and the film shows a good response and repeatability as a humidity sensing materials. This work showed that rf power and thermal annealing has significant effects on the chemical bonding and surface morphology of the a-CNx films and but yield films which are potential candidate as humidity sensor device

  10. Annealing texture of nanostructured IF steel

    International Nuclear Information System (INIS)

    In the present work, the evolution of annealing texture in nanostructured interstitial free steel fabricated via accumulative roll bonding (ARB) process was investigated. Textural evolution after post-annealing of ARB-processed samples was evaluated using X-ray diffraction. There were several texture transitions in the γ-fiber and ζ-fiber during ARB and post-annealing treatment. It was found that with increasing the number of ARB cycles, the volume fraction of the low angle grain boundary decreased and the high angle grain boundary fraction increased. Also, the shear texture was dominant after the first cycle, while for other samples, the rolling texture was dominant. The one-cycle sample clearly indicated a weak α-fiber and γ-fiber and a relatively strong ζ-fiber. In addition, during the recrystallization and before the grain growth, the intensity of α-fiber and γ-fiber decreased, the intensity of ζ-fiber increased, and the intensity of (011)〈100〉 orientation in the ε-fiber and η-fiber increased. Moreover, it was concluded that the transition from the rolling texture to the shear one was a sign of occurrence of the recrystallization (before the grain growth). Finally, with increasing the number of ARB cycles, the intensity of rolling and shear textures saturated and a stable texture formed. - Highlights: • There were texture transitions in the γ-fiber and ζ-fiber. • When the number of cycles increased, the low angle grain boundaries decreased. • The shear texture was dominant after the first cycle. • Transition from rolling texture to shear one was a sign of recrystallization. • With increasing the number of ARB cycles, a stable texture formed

  11. Simulated annealing and joint manufacturing batch-sizing

    Directory of Open Access Journals (Sweden)

    Sarker Ruhul

    2003-01-01

    Full Text Available We address an important problem of a manufacturing system. The system procures raw materials from outside suppliers in a lot and processes them to produce finished goods. It proposes an ordering policy for raw materials to meet the requirements of a production facility. In return, this facility has to deliver finished products demanded by external buyers at fixed time intervals. First, a general cost model is developed considering both raw materials and finished products. Then this model is used to develop a simulated annealing approach to determining an optimal ordering policy for procurement of raw materials and also for the manufacturing batch size to minimize the total cost for meeting customer demands in time. The solutions obtained were compared with those of traditional approaches. Numerical examples are presented. .

  12. Static Security Enhancement and Loss Minimization Using Simulated Annealing

    Directory of Open Access Journals (Sweden)

    A.Y. Abdelaziz

    2013-03-01

    Full Text Available This paper presents a developed algorithm for optimal placement of thyristor controlled series capacitors (TCSC’s for enhancing the power system static security and minimizing the system overall power loss. Placing TCSC’s at selected branches requires analysis of the system behavior under all possible contingencies. A selective procedure to determine the locations and settings of the thyristor controlled series capacitors is presented. The locations are determined by evaluating contingency sensitivity index (CSI for a given power system branch for a given number of contingencies. This criterion is then used to develop branches prioritizing index in order to rank the system branches possible for placement of the thyristor controlled series capacitors. Optimal settings of TCSC’s are determined by the optimization technique of simulated annealing (SA, where settings are chosen to minimize the overall power system losses. The goal of the developed methodology is to enhance power system static security by alleviating/eliminating overloads on the transmission lines and maintaining the voltages at all load buses within their specified limits through the optimal placement and setting of TCSC’s under single and double line outage network contingencies. The proposed algorithm is examined using different IEEE standard test systems to shown its superiority in enhancing the system static security and minimizing the system losses.

  13. Solubilization of tea seed oil in a food-grade water-dilutable microemulsion.

    Directory of Open Access Journals (Sweden)

    Lingli Deng

    Full Text Available Food-grade microemulsions containing oleic acid, ethanol, Tween 20, and water were formulated as a carrier system for tea seed oil (Camellia oleifera Abel.. The effect of ethanol on the phase behavior of the microemulsion system was clearly reflected in pseudo-ternary diagrams. The solubilization capacity and solubilization efficiency of tea seed oil dispersions were measured along the dilution line at a 70/30 surfactant/oil mass ratio with Tween 20 as the surfactant and oleic acid and ethanol (1:3, w/w as the oil phase. The dispersed phase of the microemulsion (1.5% weight ratio of tea seed oil to the total amount of oil, surfactant, and tea seed oil could be fully diluted with water without phase separation. Differential scanning calorimetry and viscosity measurements indicated that both the carrier and solubilized systems underwent a similar microstructure transition upon dilution. The dispersion phases gradually inverted from the water-in-oil phase ( 45% water along the dilution line.

  14. Synergistic cosolubilization of omega-3 fatty acid esters and CoQ10 in dilutable microemulsions.

    Science.gov (United States)

    Deutch-Kolevzon, Rivka; Aserin, Abraham; Garti, Nissim

    2011-10-01

    Water-dilutable microemulsions were prepared and loaded with two types of omega-3 fatty acid esters (omega-3 ethyl esters, OEE; and omega-3 triacylglycerides, OTG), each separately and together with ubiquinone (CoQ(10)). The microemulsions showed high and synergistic loading capabilities. The linear fatty acid ester (OEE) solubilization capacity was greater than that of the bulky and robust OTG. The location of the guest molecules within the microemulsions at any dilution point were determined by electrical conductivity, viscosity, DSC, SAXS, cryo-TEM, SD-NMR, and DLS. We found that OEE molecules pack well within the surfactant tails to form reverse micelles that gradually, upon water dilution, invert into bicontinuous phase and finally into O/W droplets. The CoQ(10) increases the stabilization and solubilization of the omega-3 fatty acid esters because it functions as a kosmotropic agent in the micellar system. The hydrophobic and bulky OTG molecule strongly interferes with the tail packing and spaces them significantly - mainly in the low and medium range water dilutions. When added to the micellar system, CoQ(10) forms some reverse hexagonal mesophases. The inversion into direct micelles is more difficult in comparison to the OEE system and requires additional water dilution. The OTG with or without CoQ(10) destabilizes the structures and decreases the solubilization capacity since it acts as a chaotropic agent to the micellar system and as a kosmotropic agent to hexagonal packing. These results explain the differences in the behavior of these molecules with vehicles that solubilize them in aqueous phases. Temperature disorders the bicontinuous structures and reduces the supersaturation of the system containing OEE with CoQ(10); as a result CoQ(10) crystallization is retarded. PMID:21723268

  15. Influence of sputtering conditions on the optical and electrical properties of laser-annealed and wet-etched room temperature sputtered ZnO:Al thin films

    Energy Technology Data Exchange (ETDEWEB)

    Boukhicha, Rym, E-mail: rym.boukhicha@polytechnique.edu [CNRS, LPICM, Ecole Polytechnique, 91128 Palaiseau (France); Charpentier, Coralie [CNRS, LPICM, Ecole Polytechnique, 91128 Palaiseau (France); Total S and M — New Energies Division, R and D Division, Department of Solar Energies EN/BO/RD/SOL, Tour Michelet, 24 cours Michelet, La Défense 10, 92069 Paris La Défense Cedex (France); Prod' Homme, Patricia [Total S and M — New Energies Division, R and D Division, Department of Solar Energies EN/BO/RD/SOL, Tour Michelet, 24 cours Michelet, La Défense 10, 92069 Paris La Défense Cedex (France); Roca i Cabarrocas, Pere [CNRS, LPICM, Ecole Polytechnique, 91128 Palaiseau (France); Lerat, Jean-François; Emeraud, Thierry [Photovoltaic Business Unit, Excico Group NV, Kempische Steenweg 305/2, B-3500 Hasselt (Belgium); Johnson, Erik [CNRS, LPICM, Ecole Polytechnique, 91128 Palaiseau (France)

    2014-03-31

    We explore the influence of the sputtering deposition conditions on the outcome of an excimer laser anneal and chemical etching process with the goal of producing highly textured substrates for thin film silicon solar cells. Aluminum-doped zinc oxide (ZnO:Al) thin films were prepared on glass substrates by radio frequency magnetron sputtering from a ceramic target at room temperature. The effects of the process pressure (0.11–1.2 Pa) and oxygen flow (0–2 sccm) on the optical and electrical properties of ZnO:Al thin films have been studied both before and after an excimer laser annealing treatment followed by a dilute HCl chemical etch. The as-deposited films varied from completely opaque to yellowish. Thin film laser annealing dramatically improves the optical properties of the most opaque thin films. After laser annealing at the optimum fluence, the average transmittance in the visible wavelength range was around 80% for most films, and reasonable electrical performance was obtained for the films deposited at lower pressures and without oxygen flux (7 Ω/□ for films of 1 μm). After etching, all films displayed a dramatic improvement in haze, but only the low pressure, low oxygen films retained acceptable electrical properties (< 11 Ω/□). - Highlights: • Al:ZnO thin films were deposited at room temperature. • The ZnO:Al films were excimer laser annealed and then wet-etched. • The optical and electrical properties were studied in details.

  16. Error correction for encoded quantum annealing

    Science.gov (United States)

    Pastawski, Fernando; Preskill, John

    2016-05-01

    Recently, W. Lechner, P. Hauke, and P. Zoller [Sci. Adv. 1, e1500838 (2015), 10.1126/sciadv.1500838] have proposed a quantum annealing architecture, in which a classical spin glass with all-to-all pairwise connectivity is simulated by a spin glass with geometrically local interactions. We interpret this architecture as a classical error-correcting code, which is highly robust against weakly correlated bit-flip noise, and we analyze the code's performance using a belief-propagation decoding algorithm. Our observations may also apply to more general encoding schemes and noise models.

  17. Binary Sparse Phase Retrieval via Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Wei Peng

    2016-01-01

    Full Text Available This paper presents the Simulated Annealing Sparse PhAse Recovery (SASPAR algorithm for reconstructing sparse binary signals from their phaseless magnitudes of the Fourier transform. The greedy strategy version is also proposed for a comparison, which is a parameter-free algorithm. Sufficient numeric simulations indicate that our method is quite effective and suggest the binary model is robust. The SASPAR algorithm seems competitive to the existing methods for its efficiency and high recovery rate even with fewer Fourier measurements.

  18. Batch-annealed dual-phase steel

    International Nuclear Information System (INIS)

    Dual-phase steel, consisting essentially of a ferrite matrix containing islands of martensite, is produced by batch annealing of hot or cold rolled steel having carbon below 0.2% and manganese below 2% and at least critical contents of copper (0.4%) and nickel (0.6%), with heat to the alpha plus gamma region, followed by slow cooling. This procedure is effective and controllable, and yields a dual-phase steel product that has high tensile strength with excellent elongation properties and that develops good yield strength upon moderate deformation

  19. Asymptotic Behavior of a Chemostat Model with Stochastic Perturbation on the Dilution Rate

    Directory of Open Access Journals (Sweden)

    Chaoqun Xu

    2013-01-01

    Full Text Available We present a stochastic simple chemostat model in which the dilution rate was influenced by white noise. The long time behavior of the system is studied. Mainly, we show how the solution spirals around the washout equilibrium and the positive equilibrium of deterministic system under different conditions. Furthermore, the sufficient conditions for persistence in the mean of the stochastic system and washout of the microorganism are obtained. Numerical simulations are carried out to support our results.

  20. Operation features of the dilution refrigerator with condensation pumping

    International Nuclear Information System (INIS)

    Dilution refrigerators with cryogenic circulation cycle of 3 He have advantages in comparison with other models. One of the most promising designs of such refrigerators is the dilution refrigerator with condensation pumping of 3 He. The design is described and its operation analyzed

  1. The Heats of Dilution Calorimetry and Van't-Hoff

    CERN Document Server

    Stepanov, I A

    2000-01-01

    Earlier it has been found that there is a big difference between heats of dilution measured by calorimetry and by the Van't-Hoff equation. In the present paper a reason for that is proposed. Experimental data for dilution of benzene and n-hexane in water were used.

  2. The Melt-Dilute Treatment Technology Offgas Development Status Report

    International Nuclear Information System (INIS)

    The melt-dilute treatment technology is being developed to facilitate the ultimate disposition of highly enriched Al-Base DOE spent nuclear fuels in a geologic repository such as that proposed for Yucca Mountain. The melt-dilute process is a method of preparing DOE spent nuclear fuel for long term storage

  3. The Heats of Dilution. Calorimetry and Van't-Hoff

    OpenAIRE

    Stepanov, I. A.

    2000-01-01

    Earlier it has been found that there is a big difference between heats of dilution measured by calorimetry and by the Van't-Hoff equation. In the present paper a reason for that is proposed. Experimental data for dilution of benzene and n-hexane in water were used.

  4. Water Metabolism of Walruses by Isotope Dilution

    DEFF Research Database (Denmark)

    Acquarone, M.; Born, E. W.; Chwalibog, A.; Griffiths, D.

    In August 2000, the hydrogen isotope dilution method was used on 7 adult male Atlantic walruses (Odobenus rosmarus rosmarus) (weight: 1197±148 kg, mean±SD, range 1013-1508 kg) at a terrestrial haul-out in Northeastern Greenland to determine their body water pool sizes and body water turnover rates...... was sampled via an epidural catheter, at regular intervals, for up to seven hours after the initial enrichment to assess isotope equilibration in the body water pools. Five individuals returned to the haul-out after feeding trips of varying duration (158±86 hr, 44-287 hr) where they were immobilized...... again and sampled for blood. The equilibration time for the isotope was found to be as short as 2 hours, total body water contents ranged between 60 and 64% of the calculated total body mass, and the half-life of body water ranged between 3.03 and 33.39 days. The results indicate that stable isotopes...

  5. Quenching of dilute Be-H alloys

    International Nuclear Information System (INIS)

    Be is a relevant material in nuclear and reactor technology. It has recently gained additional prominence as a coating material for Tokamak fusion devices. In this latter context, the reactions of Be with the hydrogen isotopes are very important. Recently, rather precise hydrogen solubility measurements both in α-Be and in β-Be became available. This paper presents an adapted form the solubility of H in Be in the α-phase. The solubility in terms of the atom ratio H/M can be expressed by: S = 1.723 x 10-4 sq. root p exp(-16700/RT) [H][M] where p is the pressure in MPa, T the temperature and R the gas constant. Thus, α-Be is an endothermic occluder of hydrogen. Another endothermic occluder of H is, for instance, Cu where TEM techniques showed the quenching of dilute Cu-H alloys from high temperatures leads to the formation of hydrogen bubbles around room temperature. Matter is ejected from the growing bubble by prismatic dislocation loop punching. In other TEM studies, it was established that quenching of the exothermic occluder of hydrogen, Mg, does not lead to bubble precipitation but to the formation of small hydride particles

  6. Spin photocurrents in diluted magnetic semiconductors

    International Nuclear Information System (INIS)

    We report on the observation of spin photocurrents resulting from the zero-bias spin separation in diluted magnetic semiconductors (DMS). We show that in (001)-grown (Cd,Mn)Te/(Cd,Mg)Te quantum wells the absorption of THz radiation leads to pure spin currents. Although the electric current is zero, spin up and down carriers pile up on opposed sample edges. By means of an in plane magnetic field B the balance between the spin currents is disturbed due to the Zeeman splitting and leads to a electron flow increasing with B. In DMS this conversion is strongly enhanced due to the giant Zeeman splitting and the spin-dependent exchange scattering of e- by Mn2+ ions polarized in the external magnetic field. Both contributions affect the balance between the contrarily spin flows additionally and give rise to the electric current. For weak B and a degenerated 2DEG the scattering mechanism dominates the conversion. We demonstrate the importance of the spin-dependent scattering in the current generation giving an additional access to the manipulation of spin-polarized currents.

  7. Dispersal and air entrainment in unconfined dilute pyroclastic density currents

    Science.gov (United States)

    Andrews, Benjamin J.

    2014-09-01

    Unconfined scaled laboratory experiments show that 3D structures control the behavior of dilute pyroclastic density currents (PDCs) during and after liftoff. Experiments comprise heated and ambient temperature 20 μm talc powder turbulently suspended in air to form density currents within an unobstructed 8.5 × 6 × 2.6-m chamber. Comparisons of Richardson, thermal Richardson, Froude, Stokes, and settling numbers and buoyant thermal to kinetic energy densities show good agreement between experimental currents and dilute PDCs. The experimental Reynolds numbers are lower than those of PDCs, but the experiments are fully turbulent; thus, the large-scale dynamics are similar between the two systems. High-frequency, simultaneous observation in three orthogonal planes shows that the currents behave very differently than previous 2D (i.e., confined) currents. Specifically, whereas ambient temperature currents show radial dispersal patterns, buoyancy reversal, and liftoff of heated currents focuses dispersal along narrow axes beneath the rising plumes. The aspect ratios, defined as the current length divided by a characteristic width, are typically 2.5-3.5 in heated currents and 1.5-2.5 in ambient temperature currents, reflecting differences in dispersal between the two types of currents. Mechanisms of air entrainment differ greatly between the two currents: entrainment occurs primarily behind the heads and through the upper margins of ambient temperature currents, but heated currents entrain air through their lateral margins. That lateral entrainment is much more efficient than the vertical entrainment, >0.5 compared to ˜0.1, where entrainment is defined as the ratio of cross-stream to streamwise velocity. These experiments suggest that generation of coignimbrite plumes should focus PDCs along narrow transport axes, resulting in elongate rather than radial deposits.

  8. Annealing-induced Ge/Si(100) island evolution

    International Nuclear Information System (INIS)

    Ge/Si(100) islands were found to coarsen during in situ annealing at growth temperature. Islands were grown by molecular-beam epitaxy of pure Ge and annealed at substrate temperatures of T=450, 550, 600, and 650 deg. C, with Ge coverages of 6.5, 8.0, and 9.5 monolayers. Three coarsening mechanisms operate in this temperature range: wetting-layer consumption, conventional Ostwald ripening, and Si interdiffusion. For samples grown and annealed at T=450 deg. C, consumption of a metastably thick wetting layer causes rapid initial coarsening. Slower coarsening at longer annealing times occurs by conventional Ostwald ripening. Coarsening of samples grown and annealed at T=550 deg. C occurs via a combination of Si interdiffusion and conventional Ostwald ripening. For samples grown and annealed at T≥600 deg. C, Ostwald ripening of SiGe alloy clusters appears to be the dominant coarsening mechanism

  9. Microstructural evolution of ECAPed 1050 alloy under magnetic annealing

    Science.gov (United States)

    Cao, Yi-heng; Jia, Pin-feng; Wang, Kang; He, Li-zi; Wang, Ping; Cui, Jian-zhong

    2014-12-01

    Hardness and microstructure evolutions in 1050 aluminum alloy prepared by equal-channel angular pressing (ECAP) were investigated by hardness testing, optical microscopy, and transmission electron microscopy after samples were annealed at different temperatures for 1 h both in the absence and presence of a 12-T magnetic field. The results showed that the hardness of samples after magnetic annealing were lower than that of samples after normal annealing at 150-250°C, but it was higher than that of samples after normal annealing at >250°C. During annealing, the rate of softening was faster, and the grains were more homogeneous in 8-ECAPed samples than in 2-ECAPed samples. A rapid grain growth occurred when 2-ECAPed samples were annealed at high temperature (≥300°C). The magnetic field enhanced the mobility of dislocations and grain boundaries. A more homogeneous grain size was observed in samples prepared under an applied magnetic field.

  10. Visible photoluminescence from the annealed TEOS SiO2

    International Nuclear Information System (INIS)

    We report the visible photoluminescence (PL) excited by Ar-ion laser (514.5 nm) at room temperature from the TEOS SiO2 films annealed under the protection of flowing N2. It was found that the PL peak position located at between 610 and 640 nm does not significantly change with the annealing temperature (T anneal). The PL intensity of TEOS SiO2 films first exhibits a gradual increase as T anneal is below 850 deg. C; thereafter it keeps almost constant when 850 deg. C anneal anneal is increased up to 1200 deg. C. The results of Raman scattering, Fourier-Transform infrared absorption and X-ray photoelectron spectra indicate that the PL mechanism in TEOS SiO2 films should be attributed to the defect emission at the surface of the SiO2 film

  11. Preparation and Thermal Characterization of Annealed Gold Coated Porous Silicon

    Directory of Open Access Journals (Sweden)

    Afarin Bahrami

    2012-01-01

    Full Text Available Porous silicon (PSi layers were formed on a p-type Si wafer. Six samples were anodised electrically with a 30 mA/cm2 fixed current density for different etching times. The samples were coated with a 50–60 nm gold layer and annealed at different temperatures under Ar flow. The morphology of the layers, before and after annealing, formed by this method was investigated by scanning electron microscopy (SEM. Photoacoustic spectroscopy (PAS measurements were carried out to measure the thermal diffusivity (TD of the PSi and Au/PSi samples. For the Au/PSi samples, the thermal diffusivity was measured before and after annealing to study the effect of annealing. Also to study the aging effect, a comparison was made between freshly annealed samples and samples 30 days after annealing.

  12. Study on thermal annealing of cadmium zinc telluride (CZT) crystals

    Energy Technology Data Exchange (ETDEWEB)

    Yang, G.; Bolotnikov, A.E.; Fochuk, P.M.; Camarda, G.S.; Cui, Y.; Hossain, A.; Kim, K.; Horace, J.; McCall, B.; Gul, R.; Xu, L.; Kopach, O.V.; and James, R.B.

    2010-08-01

    Cadmium Zinc Telluride (CZT) has attracted increasing interest with its promising potential as a room-temperature nuclear-radiation-detector material. However, different defects in CZT crystals, especially Te inclusions and dislocations, can degrade the performance of CZT detectors. Post-growth annealing is a good approach potentially to eliminate the deleterious influence of these defects. At Brookhaven National Laboratory (BNL), we built up different facilities for investigating post-growth annealing of CZT. Here, we report our latest experimental results. Cd-vapor annealing reduces the density of Te inclusions, while large temperature gradient promotes the migration of small-size Te inclusions. Simultaneously, the annealing lowers the density of dislocations. However, only-Cd-vapor annealing decreases the resistivity, possibly reflecting the introduction of extra Cd in the lattice. Subsequent Te-vapor annealing is needed to ensure the recovery of the resistivity after removing the Te inclusions.

  13. Results of Waste Transfer and Back-Dilution in Tanks 241-SY-101 and 241-SY-102

    International Nuclear Information System (INIS)

    This report chronicles the process of remediation of the flammable gas hazard in Tank 241-SY-101 (SY-101) by waste transfer and back-dilution from December 18, 1999 through April 2, 2000. A brief history is given of the development of the flammable gas retention and release hazard in this tank, and the transfer and dilution systems are outlined. A detailed narrative of each of the three transfer and dilution campaigns is given to provide structure for the balance of the report. Details of the behavior of specific data are then described, including the effect of transfer and dilution on the waste levels in Tanks SY-101 and SY-102, data from strain gauges on equipment suspended from the tank dome, changes in waste configuration as inferred from neutron and gamma logs, headspace gas concentrations, waste temperatures, and the mixerpump operating performance. Operating data and performance of the transfer pump in SY-101 are also discussed

  14. Assessment of effective parameters on dilution using approximate reasoning methods in longwall mining method, Iran coal mines

    CERN Document Server

    Owladeghaffari, H; Saeedi, G H R

    2008-01-01

    Approximately more than 90% of all coal production in Iranian underground mines is derived directly longwall mining method. Out of seam dilution is one of the essential problems in these mines. Therefore the dilution can impose the additional cost of mining and milling. As a result, recognition of the effective parameters on the dilution has a remarkable role in industry. In this way, this paper has analyzed the influence of 13 parameters (attributed variables) versus the decision attribute (dilution value), so that using two approximate reasoning methods, namely Rough Set Theory (RST) and Self Organizing Neuro- Fuzzy Inference System (SONFIS) the best rules on our collected data sets has been extracted. The other benefit of later methods is to predict new unknown cases. So, the reduced sets (reducts) by RST have been obtained. Therefore the emerged results by utilizing mentioned methods shows that the high sensitive variables are thickness of layer, length of stope, rate of advance, number of miners, type of...

  15. The role of particles annealing temperature on magnetorheological effect

    OpenAIRE

    Sedlačík, M.; Pavlínek, V.; Sáha, P.; Švrčinová, P. (Petra); Filip, P.

    2012-01-01

    The spinel nanocrystalline cobalt ferrite (CoFe.sub.2./sub.O.sub.4./sub.) particles were prepared via a solgel method followed by the annealing process. Their structural, magnetic and magnetorheological (MR) properties depending upon the annealing temperature were investigated. The X-ray diffraction analysis revealed that the higher annealing temperature, the larger grain size of CoFe.sub.2./sub.O.sub.4./sub. particles resulting in larger magnetic domains in particles. The saturation magnetiz...

  16. The role of particles annealing temperature on magnetorheological effect

    OpenAIRE

    Sedlačík, M.; Pavlínek, V.; Sáha, P.; Švrčinová, P. (Petra); Filip, P.

    2011-01-01

    The spinel cobalt ferrite (CoFe.sub.2./sub.O.sub.4./sub.) nanoparticles were prepared via a sol-gel method followed by the annealing process. Their structural, magnetic and magnetorheological (MR) properties depending upon the annealing temperature were investigated. The X-ray diffraction analysis revealed that the higher annealing temperature, the larger grain size of CoFe.sub.2./sub.O.sub.4./sub. particles resulting in larger magnetic domains in particles. The saturation magnetization, dete...

  17. Tunneling through high energy barriers in simulated quantum annealing

    OpenAIRE

    Crosson, Elizabeth; Deng, Mingkai

    2014-01-01

    We analyze the performance of simulated quantum annealing (SQA) on an optimization problem for which simulated classical annealing (SA) is provably inefficient because of a high energy barrier. We present evidence that SQA can pass through this barrier to find the global minimum efficiently. This demonstrates the potential for SQA to inherit some of the advantages of quantum annealing (QA), since this problem has been previously shown to be efficiently solvable by quantum adiabatic optimization.

  18. Annealing effect and stability of carbon nanotubes in hydrogen flame

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Annealing of carbon nanotubes (CNTs) by the hydrogen flame in air was investigated in this study. Raman spectroscopy and scanning electron microscopy were used to characterize the products. The peak width of Raman spectra decreased with the increase in the annealing time. The CNTs were not stable in the hydrogen flame and the etching rate of the CNTs by hydrogen flame was very high. The hydrogen flame annealing had some effects on improving the crystallinity of CNTs.

  19. ANNEALING OF HOT-CARRIER-INDUCED MOSFET DEGRADATION

    OpenAIRE

    Mahnkopf, R.; Przyrembel, G.; Wagemann, H.

    1988-01-01

    The annealing of fixed oxide charge and interface states generated by hot-carrier stress is investigated in the temperature range of 100°C - 450°C. First order rate equations are given, which approximately describe two subsequent processes involved in the annealing and ending at neutralization. The related activation energies are determined. For comparison the annealing of synchrotron light induced damage is examined.

  20. Magnetic field annealing for improved creep resistance

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Michael P.; Ludtka, Gail M.; Ludtka, Gerard M.; Muralidharan, Govindarajan; Nicholson, Don M.; Rios, Orlando; Yamamoto, Yukinori

    2015-12-22

    The method provides heat-resistant chromia- or alumina-forming Fe-, Fe(Ni), Ni(Fe), or Ni-based alloys having improved creep resistance. A precursor is provided containing preselected constituents of a chromia- or alumina-forming Fe-, Fe(Ni), Ni(Fe), or Ni-based alloy, at least one of the constituents for forming a nanoscale precipitate MaXb where M is Cr, Nb, Ti, V, Zr, or Hf, individually and in combination, and X is C, N, O, B, individually and in combination, a=1 to 23 and b=1 to 6. The precursor is annealed at a temperature of 1000-1500.degree. C. for 1-48 h in the presence of a magnetic field of at least 5 Tesla to enhance supersaturation of the M.sub.aX.sub.b constituents in the annealed precursor. This forms nanoscale M.sub.aX.sub.b precipitates for improved creep resistance when the alloy is used at service temperatures of 500-1000.degree. C. Alloys having improved creep resistance are also disclosed.