The thermoluminescence glow-curve analysis using GlowFit - the new powerful tool for deconvolution

International Nuclear Information System (INIS)

Puchalska, M.; Bilski, P.

2005-10-01

A new computer program, GlowFit, for deconvoluting first-order kinetics thermoluminescence (TL) glow-curves has been developed. A non-linear function describing a single glow-peak is fitted to experimental points using the least squares Levenberg-Marquardt method. The main advantage of GlowFit is in its ability to resolve complex TL glow-curves consisting of strongly overlapping peaks, such as those observed in heavily doped LiF:Mg,Ti (MTT) detectors. This resolution is achieved mainly by setting constraints or by fixing selected parameters. The initial values of the fitted parameters are placed in the so-called pattern files. GlowFit is a Microsoft Windows-operated user-friendly program. Its graphic interface enables easy intuitive manipulation of glow-peaks, at the initial stage (parameter initialization) and at the final stage (manual adjustment) of fitting peak parameters to the glow-curves. The program is freely downloadable from the web site www.ifj.edu.pl/NPP/deconvolution.htm (author)

Glow discharging device

International Nuclear Information System (INIS)

Maeno, Katsuki; Kawasaki, Kozo; Hiratsuka, Hajime; Kawashima, Shuichi.

1989-01-01

In a thermonuclear device, etc. impurities adsorbed to inner walls of a vacuum vessel by glow discharge are released to clean the vacuum vessel for preventing intrusion of the impurities into plasmas. The object of the present invention is to minimize the capacity of a power source equipment for the glow discharge device to the least extent. That is, a stabilization resistance is connected in series between each of a plurality of anodes which are inserted and arranged at the inside of a vacuum vessel as a cathode and a power source respectively. The resistance value R is selected so as to satisfy the relation: R < (Vi - Vm)/Ii, in which Vi: glow discharge starting voltage, Vm: glow discharge keeping voltage, Ii: glow discharge starting current. Accordingly, if a voltage is applied from a power source to a plurality of anodes, scattering of electric discharge between the anodes can be suppressed and the effect of voltage drop during discharge by the stabilization resistance can be eliminated. As a result, it is possible to provide an economically advantageous glow discharge device with the capacity for the power source facility being to the least extent. (K.M.)

Is the negative glow plasma of a direct current glow discharge negatively charged?

International Nuclear Information System (INIS)

Bogdanov, E. A.; Saifutdinov, A. I.; Demidov, V. I.; Kudryavtsev, A. A.

2015-01-01

A classic problem in gas discharge physics is discussed: what is the sign of charge density in the negative glow region of a glow discharge? It is shown that traditional interpretations in text-books on gas discharge physics that states a negative charge of the negative glow plasma are based on analogies with a simple one-dimensional model of discharge. Because the real glow discharges with a positive column are always two-dimensional, the transversal (radial) term in divergence with the electric field can provide a non-monotonic axial profile of charge density in the plasma, while maintaining a positive sign. The numerical calculation of glow discharge is presented, showing a positive space charge in the negative glow under conditions, where a one-dimensional model of the discharge would predict a negative space charge

Luminescence properties of pure and doped CaSO4 nanorods irradiated by 15 MeV e-beam

International Nuclear Information System (INIS)

Salah, Numan; Alharbi, Najlaa D.; Enani, Mohammad A.

2014-01-01

Calcium sulfate (CaSO 4 ) doped with proper activators is a highly sensitive phosphor used in different fields mainly for radiation dosimetry, lighting and display applications. In this work pure and doped nanorods of CaSO 4 were produced by the co-precipitation technique. Samples from this material doped with Ag, Cu, Dy, Eu and Tb were exposed to different doses of 15 MeV e-beam and studied for their thermoluminesence (TL) and photoluminescence (PL) properties. Color center formation leading to PL emissions were investigated before and after e-beam irradiation. The samples doped with rare earths elements (i.e. Dy, Eu and Tb) were observed to have thinner nanorods than the other samples and have higher absorption in the UV region. The Ag and Tb doped samples have poor TL response to e-beam, while those activated by Cu, Dy and Eu have strong glow peaks at around 123 °C. Quite linear response curves in the whole studied exposures i.e. 0.1–100 Gy were also observed in Cu and Dy doped samples. The PL results show that pure CaSO 4 nanorods have active color centers without irradiation, which could be enriched/modified by these impurities mainly rare earths and further enhanced by e-beam irradiation. Eu 3+ → Eu 2+ conversion is clearly observed in Eu doped sample after e-beam irradiation. These results show that these nanorods might be useful in lighting and display devices development

Glow discharge in singlet oxygen

International Nuclear Information System (INIS)

Vagin, N.P.; Ionin, A.A.; Klimachev, Yu.M.; Sinitsyn, D.V.; Yuryshev, N.N.; Kochetov, I.V.; Napartovich, A.P.

2003-01-01

Currently, there is no experimental data on the plasma balance in gas mixtures with a high content of singlet delta oxygen O 2 ( 1 Δ g ). These data can be obtained by studying the parameters of an electric discharge in singlet oxygen produced by a chemical generator. The O 2 ( 1 Δ g ) molecules significantly change the kinetics of electrons and negative ions in plasma. Hence, the discharge conditions at low and high O 2 ( 1 Δ g ) concentrations are very different. Here, the parameters of the positive column of a glow discharge in a gas flow from a chemical singlet-oxygen generator are studied. It is experimentally shown that, at an O 2 ( 1 Δ g ) concentration of 50% and at pressures of 1.5 and 2 torr, the electric field required to sustain the discharge is considerably lower than in the case when all of the oxygen molecules are in the ground state. A theoretical model of the glow discharge is proposed whose predictions are in good agreement with the experimental data

Computational study of plasma sustainability in radio frequency micro-discharges

International Nuclear Information System (INIS)

Zhang, Y.; Jiang, W.; Zhang, Q. Z.; Bogaerts, A.

2014-01-01

We apply an implicit particle-in-cell Monte-Carlo (PIC-MC) method to study a radio-frequency argon microdischarge at steady state in the glow discharge limit, in which the microdischarge is sustained by secondary electron emission from the electrodes. The plasma density, electron energy distribution function (EEDF), and electron temperature are calculated in a wide range of operating conditions, including driving voltage, microdischarge gap, and pressure. Also, the effect of gap size scaling (in the range of 50-1000 μm) on the plasma sustaining voltage and peak electron density at atmospheric pressure is examined, which has not been explored before. In our simulations, three different EEDFs, i.e., a so-called three temperature hybrid mode, a two temperature α mode, and a two temperature γ mode distribution, are identified at different gaps and voltages. The maximum sustaining voltage to avoid a transition from the glow mode to an arc is predicted, as well as the minimum sustaining voltage for a steady glow discharge. Our calculations elucidate that secondary electrons play an essential role in sustaining the discharge, and as a result the relationship between breakdown voltage and gap spacing is far away from the Paschen law at atmospheric pressure

Spectroscopic characterisation of an atmospheric pressure glow discharge

International Nuclear Information System (INIS)

Gomez, S.; Steen, P.G.; Morrow, T.; Graham, W.G.

2001-01-01

Recently there has been considerable interest in atmospheric discharges operating in a glow discharge mode i.e. with a spatial and sheath structure similar to that of low pressure glow discharges. Here spectroscopy has been used to characterise an atmospheric pressure glow discharge (APGD), operating with either dry air, argon or helium gas flowing through the inter-electrode space and with the inter-electrode gap either free or with woven polypropylene or polyester samples present. Emission spectroscopy is used to determine the rotational and vibrational temperature of the nitrogen gas, while electron temperatures are determined from the relative intensities of Ar emission lines. Ozone production is monitored by a simple absorption technique to evaluate its potential in process control

Common Gamma-ray Glows above Thunderclouds

Science.gov (United States)

Kelley, Nicole; Smith, David; Dwyer, Joseph; Hazelton, Bryna; Grefenstette, Brian; Lowell, Alex; Splitt, Michael; Lazarus, Steven; Rassoul, Hamid

2013-04-01

Gamma-ray glows are continuous, long duration gamma- and x-ray emission seen coming from thunderclouds. The Airborne for Energetic Lightning Emissions (ADELE) observed 12 gamma-ray glows during its summer 2009 flight campaign over the areas of Colorado and Florida in the United States. For these glows we shall present their spectra, relationship to lightning activity and how their duration and size changes as a function of distance. Gamma-ray glows follow the relativistic runaway electron avalanche (RREA) spectrum and have been previously measured from the ground and inside the cloud. ADELE measured most glows as it flew above the screening layer of the cloud. During the brightest glow on August 21, 2009, we can show that we are flying directly into a downward facing relativistic runaway avalanche, indicative of flying between the upper positive and negative screening layer of the cloud. In order to explain the brightness of this glow, RREA with an electric field approaching the limit for relativistic feedback must be occurring. Using all 12 glows, we show that lightning activity diminishes during the onset of the glow. Using this along with the fact that glows occur as the field approaches the level necessary for feedback, we attempt to distinguish between two possibilities: that glows are evidence that RREA with feedback, rather than lightning, is sometimes the primary channel for discharging the cloud, or else that the overall discharging is still controlled by lightning, with glows simply appearing during times when a subsidence of lightning allows the field to rise above the threshold for RREA.

Extension of spatiotemporal chaos in glow discharge-semiconductor systems.

Science.gov (United States)

Akhmet, Marat; Rafatov, Ismail; Fen, Mehmet Onur

2014-12-01

Generation of chaos in response systems is discovered numerically through specially designed unidirectional coupling of two glow discharge-semiconductor systems. By utilizing the auxiliary system approach, [H. D. I. Abarbanel, N. F. Rulkov, and M. M. Sushchik, Phys. Rev. E 53, 4528-4535 (1996)] it is verified that the phenomenon is not a chaos synchronization. Simulations demonstrate various aspects of the chaos appearance in both drive and response systems. Chaotic control is through the external circuit equation and governs the electrical potential on the boundary. The expandability of the theory to collectives of glow discharge systems is discussed, and this increases the potential of applications of the results. Moreover, the research completes the previous discussion of the chaos appearance in a glow discharge-semiconductor system [D. D. Šijačić U. Ebert, and I. Rafatov, Phys. Rev. E 70, 056220 (2004).].

Luminescence properties of pure and doped CaSO{sub 4} nanorods irradiated by 15 MeV e-beam

Energy Technology Data Exchange (ETDEWEB)

Salah, Numan, E-mail: nsalah@kau.edu.sa [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Alharbi, Najlaa D. [Sciences Faculty for Girls, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Enani, Mohammad A. [Dept. of Nuclear Engineering, Faculty of Engineering, King Abdulaziz University, Jeddah 21589 (Saudi Arabia)

2014-01-15

Calcium sulfate (CaSO{sub 4}) doped with proper activators is a highly sensitive phosphor used in different fields mainly for radiation dosimetry, lighting and display applications. In this work pure and doped nanorods of CaSO{sub 4} were produced by the co-precipitation technique. Samples from this material doped with Ag, Cu, Dy, Eu and Tb were exposed to different doses of 15 MeV e-beam and studied for their thermoluminesence (TL) and photoluminescence (PL) properties. Color center formation leading to PL emissions were investigated before and after e-beam irradiation. The samples doped with rare earths elements (i.e. Dy, Eu and Tb) were observed to have thinner nanorods than the other samples and have higher absorption in the UV region. The Ag and Tb doped samples have poor TL response to e-beam, while those activated by Cu, Dy and Eu have strong glow peaks at around 123 °C. Quite linear response curves in the whole studied exposures i.e. 0.1–100 Gy were also observed in Cu and Dy doped samples. The PL results show that pure CaSO{sub 4} nanorods have active color centers without irradiation, which could be enriched/modified by these impurities mainly rare earths and further enhanced by e-beam irradiation. Eu{sup 3+} → Eu{sup 2+} conversion is clearly observed in Eu doped sample after e-beam irradiation. These results show that these nanorods might be useful in lighting and display devices development.

Extension of spatiotemporal chaos in glow discharge-semiconductor systems

International Nuclear Information System (INIS)

Akhmet, Marat; Fen, Mehmet Onur; Rafatov, Ismail

2014-01-01

Generation of chaos in response systems is discovered numerically through specially designed unidirectional coupling of two glow discharge-semiconductor systems. By utilizing the auxiliary system approach, [H. D. I. Abarbanel, N. F. Rulkov, and M. M. Sushchik, Phys. Rev. E 53, 4528–4535 (1996)] it is verified that the phenomenon is not a chaos synchronization. Simulations demonstrate various aspects of the chaos appearance in both drive and response systems. Chaotic control is through the external circuit equation and governs the electrical potential on the boundary. The expandability of the theory to collectives of glow discharge systems is discussed, and this increases the potential of applications of the results. Moreover, the research completes the previous discussion of the chaos appearance in a glow discharge-semiconductor system [D. D. Šijačić U. Ebert, and I. Rafatov, Phys. Rev. E 70, 056220 (2004).

Reduction of Cr(VI) in aqueous solution with DC diaphragm glow discharge

International Nuclear Information System (INIS)

Wang, Xiaoyan; Jin, Xinglong; Zhou, Minghua; Chen, Zhenhai; Deng, Kai

2013-01-01

This paper investigated the reduction of Cr(VI) in aqueous solution with direct current diaphragm glow discharge (DGD). The glow discharge sustained around the hole on a quartz tube which divided the electrolyte cell into two parts. The reduction efficiencies of Cr(VI) under different applied voltages, initial conductivities, hole diameters, hole numbers, initial pH values and initial concentrations were systematically studied. The results showed that the reduction efficiency of Cr(VI) increased with the increase of applied voltage, initial conductivity, hole diameter and hole number. The different initial pH values showed less effects on the reduction of Cr(VI). The reduction efficiency decreased with the increasing initial concentration. In addition, the simultaneous reduction of Cr(VI) and decolorization of acid orange (AO) with DGD were also fulfilled. Furthermore, the energy efficiency for Cr(VI) reduction with DGD was calculated and compared with those in photocatalysis and other glow discharge reactor

GlowPhones

DEFF Research Database (Denmark)

Merritt, Timothy Robert; Nielsen, Christine Linding; Jakobsen, Frederik Lund

2017-01-01

Location-based mobile games often utilize built-in sensors for supporting game experiences tied to the physical world, yet the visual user interface remains constrained to the small high-resolution screen. GlowPhones is a location-based mobile social game using low-resolution displays to augment...... the physical space and move the attention away from the mobile screen. Players explore the physical world and collaborate to overcome challenges relying on the screen glow intensity emitted from the phone’s screen and light flash frequency of the camera flash for navigation. Three game stages explore proxemics...

In-flight observation of long duration gamma-ray glows by aircraft

Science.gov (United States)

Kochkin, Pavlo; (Lex) van Deursen, A. P. J.; de Boer, Alte; Bardet, Michiel; Allasia, Cedric; Boissin, Jean Francois; Ostgaard, Nikolai

2017-04-01

The Gamma-Ray Glow is a long-lasting (several seconds to minutes) X- and gamma radiation presumably originated from high-electric field of thunderclouds. Such glows were previously observed by aircraft, balloons, and from the ground. When detected on ground with other particles, i.e. electrons and neutrons, they are usually called Thunderstorm Ground Enhancements (TGEs). Their measured spectra are often consistent with Relativistic Runaway Electron Avalanche (RREA) mechanism. That is why RREA is a commonly accepted explanation for their existence. The gamma-ray glows are observed to be interrupted by lightning discharge, which terminates the high-electric field region. In January 2016 an Airbus A340 factory test aircraft was performing intentional flights through thunderstorms over Northern Australia. The aircraft was equipped with a dedicated in-flight lightning detection system called ILDAS (http://ildas.nlr.nl). The system also contained two scintillation detectors each with 38x38 mm cylinder LaBr3 crystals. While being at 12 km altitude the system detected a gamma-ray flux enhancement 30 times the background counts. It lasted for 20 seconds and was abruptly terminated by a lightning flash. The flash hit the aircraft and its parameters were recorded with 10 ns sampling time including gamma radiation. Ground-based lightning detection network WWLLN detected 4 strikes in the nearby region, all in association with the same flash. The ILDAS system recorded the time-resolved spectrum of the glow. In 6 minutes, after making a U-turn, the aircraft passed the same glow region. Smaller gamma-ray enhancement was again detected. In this presentation we will show the mapped event timeline including airplane, gamma-ray glow, WWLLN, and cloud data. We will discuss the glow's properties, i.e. intensity and differential spectrum, and its possible origin. This result will also be compared to previously reported observations.

Dynamic Contraction of the Positive Column of a Self-Sustained Glow Discharge in Molecular Gas Flow

Science.gov (United States)

Shneider, Mikhail

2014-10-01

Contraction of the gas discharge, when current contracts from a significant volume of weakly ionized plasma into a thin arc channel, was attracted attention of scientists for more than a century. Studies of the contraction (also called constriction) mechanisms, besides carrying interesting science, are of practical importance, especially when contraction should be prevented. A set of time-dependent two-dimensional equations for the non-equilibrium weakly-ionized nitrogen/ air plasma is formulated. The process is described by a set of time-dependent continuity equations for the electrons, positive and negative ions; gas and vibrational temperature; by taking into account the convective heat and plasma losses by the transverse flux. Transition from the uniform to contracted state was analyzed. It was shown that such transition experiences a hysteresis, and that the critical current of the transition increases when the pressure (gas density) drops. Possible coexistence of the contracted and uniform state of the plasma in the discharge where the current flows along the density gradient of the background gas was discussed. In this talk the problems related to the dynamic contraction of the current channel inside a quasineutral positive column of a self-sustained glow discharge in molecular gas in a rectangular duct with convection cooling will be discussed. Study presented in this talk was stimulated by the fact that there are large number of experiments on the dynamic contraction of a glow discharge in nitrogen and air flows and a many of possible applications. Similar processes play a role in the powerful gas-discharge lasers. In addition, the problem of dynamic contraction in the large volume of non-equilibrium weakly ionized plasma is closely related to the problem of streamer to leader transitions in lightning and blue jets.

Micro glow plasma for localized nanostructural modification of carbon nanotube forest

Energy Technology Data Exchange (ETDEWEB)

Sarwar, Mirza Saquib us; Xiao, Zhiming; Saleh, Tanveer; Nojeh, Alireza; Takahata, Kenichi [University of British Columbia, Vancouver, British Columbia V6T 1Z4 (Canada)

2016-08-22

This paper reports the localized selective treatment of vertically aligned carbon nanotubes, or CNT forests, for radial size modification of the nanotubes through a micro-scale glow plasma established on the material. An atmospheric-pressure DC glow plasma is shown to be stably sustained on the surface of the CNT forest in argon using micromachined tungsten electrodes with diameters down to 100 μm. Experiments reveal thinning or thickening of the nanotubes under the micro glow depending on the process conditions including discharge current and process time. These thinning and thickening effects in the treated nanotubes are measured to be up to ∼30% and ∼300% in their diameter, respectively, under the tested conditions. The elemental and Raman analyses suggest that the treated region of the CNT forest is pure carbon and maintains a degree of crystallinity. The local plasma treatment process investigated may allow modification of material characteristics in different domains for targeted regions or patterns, potentially aiding custom design of micro-electro-mechanical systems and other emerging devices enabled by the CNT forest.

On the second kinetic order thermoluminescent glow curves

International Nuclear Information System (INIS)

Dang Thanh Luong; Nguyen Hao Quang; Hoang Minh Giang

1995-01-01

The kinetic parameters of thermoluminescent material such as CaF 2 -N and CaSO 4 -Dy with the different grain sizes are investigated in detail using the least square method of fitting. It was found that the activation energy E (or trap depth) and peak temperature T m ax are changed with the elapsed time between the irradiation and read-out for the low temperature glow curve peaks. The similar TL glow curve shapes are obtained for the different CaSO 4 -Dy grain size. (author). 7 refs., 5 figs., 2 tabs

Low-pressure glow discharges with oscillating electrons in different electrode systems

International Nuclear Information System (INIS)

Bersenev, V.V.; Gavriolv, N.V.; Nikulin, S.P.

1995-01-01

One of the main applications of low - pressure glow discharges is the development on their basis of charged - particle beam sources. The use of glow discharges with oscillating electrons, which can operate stably in the voltage and pressure range to the left of the left branch of Pashen's curve, shows promise, because the decrease in critical pressure p 0 , below which the discharge operation becomes impossible, in the discharge system of a source promotes an increase in the electrical strength of its accelerating system. This, in its turn, makes possible the expansion of the operation range of accelerating voltages. This experimental investigation of glow discharges in such well - known systems with oscillating electrons, as Hollow Cathode (HC), Penning's System (PS) and Inverse Magnetron (IM), is aimed at revealing the system operating at the lowest pressure. Besides, both common features and peculiarities of discharge operation in these systems are discussed. Though there is an extensive amount of published information covering all the specified discharges, the carrying out of such investigation is justified, since a comparative analysis of results obtained by different authors is hampered by various conditions of their experiments

Luminosity, Beamstrahlung energy loss and beam-beam deflections for e+e- and e-e- collisions at the ILC with 500 GeV and varying transverse beam sizes

International Nuclear Information System (INIS)

Alabau Pons, M.; Bambade, P.; Faus-Golfe, A.

2006-01-01

At the interaction point of the International Linear Collider, beam-beam effects due to the strong electromagnetic fields that the bunches experience during collisions cause a mutual focusing, called pinch effect, which enhances the luminosity in the case of e + e - collisions. The opposite is true for e - e - collisions. In this case the luminosity is reduced by mutual defocusing, or anti-pinching. The resulting Beamstrahlung energy loss and beam-beam deflection angles as function of the vertical transverse offset are also different for both modes of operation. The dependence of these quantities with transverse beam sizes are presented for the case of e - e - collisions

Glow plasma jet - experimental study of a transferred atmospheric pressure glow discharge

International Nuclear Information System (INIS)

Guerra-Mutis, Marlon H; U, Carlos V Pelaez; H, Rafael Cabanzo

2003-01-01

In this paper we present the experimental study of a glow plasma jet (GPJ) obtained from a transferred atmospheric pressure glow discharge (APGD) operating at 60 Hz. The characterization of the emission spectra for both electrical discharges is presented and the electrical circuit features for APGD generation are discussed. The potentiality of GPJ as a source of active species for depletion of contaminants in liquid hydrocarbon fractions is also established

Use of universal functional optimisation for TL glow curve analysis

International Nuclear Information System (INIS)

Pernicka, F.; Linh, H.Q.

1996-01-01

The effective use of any TL instrument requires an efficient software package to be able to fulfil different tasks required by research and practical applications. One of the standard features of the package used at the NPI Prague is the application of the interactive modular system Universal Functional Optimisation (UFO) for glow curve deconvolution. The whole system has been tested on standard glow curves using different models of the TL process (a single peak described by the Podgorsak approximation, first order kinetics and/or general order kinetics). Calculated values of basic TL parameters (E and s) show a good agreement with the results obtained by other authors. The main advantage of the system is in its modularity that enables flexible changes in the TL model and mathematical procedures of the glow curve analysis. (author)

Glow-peak stability in 6LiF:Mg, Ti (TLD-600) exposed to a Fe-ion beam

International Nuclear Information System (INIS)

Yasuda, Hiroshi

2001-01-01

The stability of glow peaks in 6 LiF:Mg, Ti (TLD-600) exposed to a high-energy Fe-ion beam was examined in comparison to 137 Cs γ-ray irradiation under changing annealing conditions. The peak areas induced by the Fe ions were much smaller than those by γ-rays. The sizes and positions of peaks 3-5 in Fe-ion irradiated samples were hardly changed after post-annealing at 100 deg C x 30 min, regardless of the pre-annealing conditions (fast quenching or subsequent pre-annealing at 100 deg C x 2 h). Whereas, the peaks in γ-ray irradiated samples were notably affected by post-annealing; the peak positions and peak-area sizes changed in different ways depending on the pre-annealing conditions. The effects of post-annealing on peak 6 were identical for Fe ions and γ-rays. These facts suggest that peaks 3-5 in TLD-600 comprised both stable and unstable luminescent centers, and that the latter part would be easily depleted in highly dense ionization. (author)

Quadrupole modes in linearized beam-beam interaction in e+e- colliding rings

International Nuclear Information System (INIS)

Matsumoto, Shuji; Hirata, Kohji.

1992-01-01

The dynamic-beta model is extended, incorporating the synchrotron radiation effects. The model yields dynamic-emittance effect. The steady-state envelope matrix is explicitly obtained. Both equal-beam and flip-flop solutions are found. The stability of the steady-state solutions are investigated by numerical calculations. The model illustrates some characteristic features of the beam-beam interaction at e + e - colliding rings in spite of containing some qualitatively unrealistic points. (author)

Changes in the artificial thermoluminescence glow curves of quartz associated with uranium deposits

Energy Technology Data Exchange (ETDEWEB)

Hochman, M.B.M.; Ypma, P.J.M.

1988-01-01

Previous laboratory-based studies have shown that quartz thermoluminescence (TL) glow curves change in intensity and shape in response to large radiation doses. Initially, low temperature peaks are sensitized though at gamma doses of greater than 10/sup 5/ - 10/sup 6/ kGy desensitization occurs. This study has examined the change in artificial TL in quartz at various distances from a uranium deposit. Such quartz has been subjected to varying palaeoradiation doses in a natural uranium rich environment. Quartz from an uranium rich environment shows that the 130/sup 0/C glow peak is the dominant glow peak in background radiation environments, though this peak decreases with increasing palaeoradiation dose. At doses greater than 10/sup 5/-10/sup 6/ kGy the 350/sup 0/C glow peak is the dominant glow peak in these quartz samples. An increase in E'/sub 1/ centre concentration also occurs from the least radiation affected sample to the most radiation affected sample. These results suggest that artificial TL is useful in uranium exploration.

Uncertainty of relative sensitivity factors in glow discharge mass spectrometry

Science.gov (United States)

Meija, Juris; Methven, Brad; Sturgeon, Ralph E.

2017-10-01

The concept of the relative sensitivity factors required for the correction of the measured ion beam ratios in pin-cell glow discharge mass spectrometry is examined in detail. We propose a data-driven model for predicting the relative response factors, which relies on a non-linear least squares adjustment and analyte/matrix interchangeability phenomena. The model provides a self-consistent set of response factors for any analyte/matrix combination of any element that appears as either an analyte or matrix in at least one known response factor.

Irradiation of wastewater with electron beam is a key to sustainable smart/green cities: a review

Science.gov (United States)

Hossain, Kaizar; Maruthi, Y. Avasn; Das, N. Lakshmana; Rawat, K. P.; Sarma, K. S. S.

2018-03-01

Remediation of wastewater, sludge and removal of objectionable substances from our environment using radiation technology is neglected. Hardly, a couple of decades ago, application of electron beam (EB) technology has gained attention for waste management. When wastewater is irradiated with electron beam, the beam can alter the physico-chemical properties of irradiated aqueous material and also transform wastewater chemicals due to the excitation or ionization of chemical molecules. Thus, chemical reactions may be capable of producing new compounds. The beam of electrons initiates primary reactions to induce the excitation or ionization of molecules at varied rates. This review paper will help to a budding researcher how to optimize the irradiation process to achieve high efficiency with low electron beam energy which is economically viable/feasible. Application of E-beam radiation for wastewater treatment may ensure future smart cities with sustainable water resources management.

Role of cathode identity in liquid chromatography particle beam glow discharge mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Krishna, M.V. Balarama [Department of Chemistry, Biosystems Research Complex, Clemson University, Clemson, SC 29634-1905 (United States); Marcus, R.K. [Department of Chemistry, Biosystems Research Complex, Clemson University, Clemson, SC 29634-1905 (United States)], E-mail: marcusr@clemson.edu

2008-06-15

A detailed evaluation of the role of cathode identity on the analytical and spectral characteristics of various organic, organometallic and metal analytes using liquid chromatography-particle beam/glow discharge mass spectrometry (LC-PB/GDMS) has been carried out. A d.c. discharge, operating with argon as the support gas, was used throughout this work. In this study, Cu which has a relatively high sputtering rate, Ni which has moderate sputtering rate and Ta which has very low sputtering rate, are taken as cathode materials to study the ionization, fragmentation, and analytical characteristics of organic (caffeine, epigallocatechin gallate, peptide as representative compounds), organometallic (selenomethionine, triethyl lead chloride as representative compounds) and metal (Fe, La, Cs and Pb) species. A range of discharge gas pressures (26.6-106.4 Pa) and currents (0.2-1.5 mA) were investigated with the test cathodes to determine their influence on the spectral composition and overall analytical response for the various test species. Calibration plots were obtained for all of the species for each of the three cathodes to determine the respective limits of detection. Relative detection limits in the range of 0.02 to 15 ng mL{sup -1} (0.002-1.5 ng, absolute) for the test species were found to be in the order of Cu > Ni > Ta; which follows the order of the sputtering characteristics of the respective cathodes. These studies rendered information about the respective discharge parameters' role in choosing the most appropriate cathode identity in PB-GDMS for application in the areas of organic, organometallic and inorganic species analysis.

Luminosity, Beamstrahlung energy loss and beam-beam deflections for e{sup +}e{sup -} and e{sup -}e{sup -} collisions at the ILC with 500 GeV and varying transverse beam sizes

Energy Technology Data Exchange (ETDEWEB)

Alabau Pons, M. [Laboratoire de l' Accelerateur Lineaire, IN2P3-CNRS et Universite de Paris-Sud XI, Bat. 200, B.P. 34, 91898 Orsay Cedex (France)]|[IFIC, Edificio Institutos de Paterna, Aptdo. 22085, 46071 Valencia (Spain); Bambade, P. [Laboratoire de l' Accelerateur Lineaire, IN2P3-CNRS et Universite de Paris-Sud XI, Bat. 200, B.P. 34, 91898 Orsay Cedex (France); Faus-Golfe, A. [IFIC, Edificio Institutos de Paterna, Aptdo. 22085, 46071 Valencia (Spain)

2006-01-15

At the interaction point of the International Linear Collider, beam-beam effects due to the strong electromagnetic fields that the bunches experience during collisions cause a mutual focusing, called pinch effect, which enhances the luminosity in the case of e{sup +}e{sup -} collisions. The opposite is true for e{sup -}e{sup -} collisions. In this case the luminosity is reduced by mutual defocusing, or anti-pinching. The resulting Beamstrahlung energy loss and beam-beam deflection angles as function of the vertical transverse offset are also different for both modes of operation. The dependence of these quantities with transverse beam sizes are presented for the case of e{sup -}e{sup -} collisions.

Detection of irradiated foods by the thermoluminescence. Relationships between the temperature ranges of integrating TL glow curves and TL glow ratios

International Nuclear Information System (INIS)

Sekiguchi, Masayuki; Yamazaki, Masao; Goto, Michiko; Todoriki, Setsuko; Hagiwara, Shoji

2007-01-01

Our study demonstrated that the effects of the several temperature ranges for integrating TL glow intensity on the TL glow ratios by using spice-set purchased at a Turkish air port. The spice set had no labeling of irradiation feeds, but nine of 12 spices were judged as irradiated food in this study. Those temperature ranges were defined by evaluating the glow curves of irradiated TLD-100 chip (167-230degC), TLD-100 disc (177-238degC) and Dolomite element (145-258degC). Those are relatively stable and the difference of typical glow peak temperatures of TLD-100 disc in two institutes was less than 2%. On the other hand, those of TLD-100 tip was shift to higher temperature side at about 4degC because of declining of thermal conductance. The temperature ranges defined by TLD-100 were showed that discriminate more clearly between irradiated and nonirradiated spices compared with the full temperature range of TL measurement (70-400degC). With the exception of low glow intensity, background measurement for estimating net glow intensity was not necessary because TL glow ratio was hardly influenced whether the background measured or not. (author)

Thermoluminescence glow-curve deconvolution functions for mixed order of kinetics and continuous trap distribution

International Nuclear Information System (INIS)

Kitis, G.; Gomez-Ros, J.M.

2000-01-01

New glow-curve deconvolution functions are proposed for mixed order of kinetics and for continuous-trap distribution. The only free parameters of the presented glow-curve deconvolution functions are the maximum peak intensity (I m ) and the maximum peak temperature (T m ), which can be estimated experimentally together with the activation energy (E). The other free parameter is the activation energy range (ΔE) for the case of the continuous-trap distribution or a constant α for the case of mixed-order kinetics

Analytical Expressions for the Mixed-Order Kinetics Parameters of TL Glow Peaks Based on the two Heating Rates Method.

Science.gov (United States)

Maghrabi, Mufeed; Al-Abdullah, Tariq; Khattari, Ziad

2018-03-24

The two heating rates method (originally developed for first-order glow peaks) was used for the first time to evaluate the activation energy (E) from glow peaks obeying mixed-order (MO) kinetics. The derived expression for E has an insignificant additional term (on the scale of a few meV) when compared with the first-order case. Hence, the original expression for E using the two heating rates method can be used with excellent accuracy in the case of MO glow peaks. In addition, we derived a simple analytical expression for the MO parameter. The present procedure has the advantage that the MO parameter can now be evaluated using analytical expression instead of using the graphical representation between the geometrical factor and the MO parameter as given by the existing peak shape methods. The applicability of the derived expressions for real samples was demonstrated for the glow curve of Li 2 B 4 O 7 :Mn single crystal. The obtained parameters compare very well with those obtained by glow curve fitting and with the available published data.

Miniature Coaxial Plasma injector Diagnostics by Beam Plasma Interaction

International Nuclear Information System (INIS)

El-Tayeb, H.; El-Gamal, H.

2003-01-01

A miniature coaxial gun has been used to study the interaction between plasma beam and low density plasma formed in glow discharge. The peak discharge current flow between the coaxial electrodes was 5.25 kA as a single pulse with pulse width of 60 mu. Investigations are carried out with argon gas at pressure 0.4 Torr. The plasma stream ejected from the coaxial discharge propagates in the neutral argon atoms with mean velocity of 1.2x10 5 cm/s. The plasma stream temperature and density were 4.2 eV and 2.4x10 13 cm -3 respectively. An argon negative glow has been used as base plasma where its electron temperature and density were 2.2 eV and 6.2x10 7 cm -3 respectively. When the plasma stream propagates through the negative glow discharge region its velocity decreased to 8.8 x 10 4 cm/s and also the plasma electron temperature decreased to 3.1 eV, while the stream density remained the same. An excited wave appeared on the electric probe having frequency equal to the plasma frequency of the plasma under consideration. Simulation of the problem showed that this method could be applied for plasma diagnostics within the region of investigation. Those further studies for high temperature, dense, and magnetized plasma will be considered

Aspects of the practical application of titanium alloys after low temperature nitriding glow discharge in hydrogen- free -gas media

International Nuclear Information System (INIS)

Mashovets, N.S.; Pastukh, I.M.; Voloshko, S.M.

2017-01-01

Highlights: • Surface modification of titanium alloys were carried out by low-temperature nitriding in a glow discharge in hydrogen-free environment. • Research into the phase composition was performed by X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). • The above material shows the promise of the technology of low-temperature hydrogen-nitriding by glow discharge. This greatly expands the range of practical applications of titanium alloys. - Abstract: X-ray diffraction analysis, X-ray photoelectron spectroscopy, and Electron Auger-spectroscopy investigation of phase transformation on the surface of the VT8 titanium alloy after a low temperature hydrogen-free nitriding in a glow discharge. Operational characteristics of titanium alloys defined physical-mechanical characteristics of the surface and their phase composition, which depend on the process parameters of nitriding. Surface modification of titanium alloys were carried out by low-temperature nitriding in a glow discharge in hydrogen-free environment. The main advantage of this method lies in the absence of hydrogen embrittlement and complete environmental safety process. Application of the glow discharge can not only speed up the process by the order of the diffusion surface saturation with nitrogen, but also significantly alters the kinetics of the process and quality of the nitrided layer, in particular its physio-mechanical properties and phase composition. For research purposes, the standards from an α + β alloy Ti-Al6-Cr2-Mo2,5 (VT8) were used. Research into the phase composition was performed by X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). Stratified analysis by AES was conducted by etching the surface of the samples’ argon ion beam with diameters of 1.5 mm with an energy of 3000 eV and a current density of 400 mA/cm 2 . The above material shows the promise of the technology of low

Aspects of the practical application of titanium alloys after low temperature nitriding glow discharge in hydrogen- free -gas media

Energy Technology Data Exchange (ETDEWEB)

Mashovets, N.S., E-mail: mashovets@rambler.ru [Khmelnickiy National University (Ukraine); Pastukh, I.M., E-mail: pastim@mail.ru [Khmelnickiy National University (Ukraine); Voloshko, S.M. [Khmelnickiy National University (Ukraine); National Technical University of Ukraine “Kyiv Polytechnic Institute” (Ukraine)

2017-01-15

Highlights: • Surface modification of titanium alloys were carried out by low-temperature nitriding in a glow discharge in hydrogen-free environment. • Research into the phase composition was performed by X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). • The above material shows the promise of the technology of low-temperature hydrogen-nitriding by glow discharge. This greatly expands the range of practical applications of titanium alloys. - Abstract: X-ray diffraction analysis, X-ray photoelectron spectroscopy, and Electron Auger-spectroscopy investigation of phase transformation on the surface of the VT8 titanium alloy after a low temperature hydrogen-free nitriding in a glow discharge. Operational characteristics of titanium alloys defined physical-mechanical characteristics of the surface and their phase composition, which depend on the process parameters of nitriding. Surface modification of titanium alloys were carried out by low-temperature nitriding in a glow discharge in hydrogen-free environment. The main advantage of this method lies in the absence of hydrogen embrittlement and complete environmental safety process. Application of the glow discharge can not only speed up the process by the order of the diffusion surface saturation with nitrogen, but also significantly alters the kinetics of the process and quality of the nitrided layer, in particular its physio-mechanical properties and phase composition. For research purposes, the standards from an α + β alloy Ti-Al6-Cr2-Mo2,5 (VT8) were used. Research into the phase composition was performed by X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). Stratified analysis by AES was conducted by etching the surface of the samples’ argon ion beam with diameters of 1.5 mm with an energy of 3000 eV and a current density of 400 mA/cm{sup 2}. The above material shows the promise of the technology of low

The role of magnetic energy on plasma localization during the glow discharge under reduced pressure

Directory of Open Access Journals (Sweden)

Chodun Rafal

2016-06-01

Full Text Available In this work, we present the first results of our research on the synergy of fields, electric and magnetic, in the initiation and development of glow discharge under reduced pressure. In the two-electrode system under reduced pressure, the breakdown voltage characterizes a minimum energy input of the electric field to initiate and sustain the glow discharge. The glow discharge enhanced by the magnetic field applied just above the surface of the cathode influences the breakdown voltage decreasing its value. The idea of the experiment was to verify whether the contribution of potential energy of the magnetic field applied around the cathode is sufficiently effective to locate the plasma of glow discharge to the grounded cathode, which, in fact, is the part of a vacuum chamber wall (the anode is positively biased in this case. In our studies, we used the grounded magnetron unit with positively biased anode in order to achieve favorable conditions for the deposition of thin films on fibrous substrates such as fabrics for metallization, assuming that locally applied magnetic field can effectively locate plasma. The results of our studies (Paschen curve with the participation of the magnetic field seem to confirm the validity of the research assumption. What is the most spectacular - the glow discharge was initiated between introduced into the chamber anode and the grounded cathode of magnetron ‘assisted’ by the magnetic field (discharge did not include the area of the anode, which is a part of the magnetron construction.

Characterization of the large area plane-symmetric low-pressure DC glow discharge

Science.gov (United States)

Avtaeva, S.; Gorokhovsky, V.; Myers, S.; Robertson, S.; Shunko, E.; Zembower, Z.

2016-10-01

Electron density and temperature as well as nitrogen dissociation degree in the low-pressure (10-50 mTorr) large area plane-symmetric DC glow discharge in Ar-N2 mixtures are studied by probes and spectral methods. Electron density measured by a hairpin probe is in good agreement with that derived from the intensity ratio of the N2 2nd positive system bands IC, 1 - 3/IC, 0 - 2 and from the intensity ratio of argon ions and atom lines IArII/IArI, while Langmuir probe data provides slightly higher values of electron density. Electron density in the low-pressure DC glow discharge varies with the discharge conditions in the limits of 108-1010 cm- 3. The concept of electron temperature can be used in low-pressure glow discharges with reservations. The intensity ratio of (0-0) vibrational bands of N2 1st negative and 2nd positive systems I391.4/I337.1 exhibits the electron temperature of 1.5-2.5 eV when argon fraction in the mixture is higher than nitrogen fraction and this ratio quickly increases with nitrogen fraction up to 10 eV in pure nitrogen. The electron temperature calculated from Langmuir probe I-V characteristics assuming a Maxwellian EEDF, gives Te 0.3-0.4 eV. In-depth analysis of the EEDF using the second derivative of Langmuir probe I-V characteristics shows that in a low-pressure glow discharge the EEDF is non-Maxwellian. The EEDF has two populations of electrons: the main background non-Maxwellian population of ;cold; electrons with the mean electron energy of 0.3-0.4 eV and the small Maxwellian population of ;hot; electrons with the mean electron energy of 1.0-2.5 eV. Estimations show that with electron temperature lower than 1 eV the rate of the direct electron impact ionization of N2 is low and the main mechanism of N2 ionization becomes most likely Penning and associative ionization. In this case, assumptions of the intensity ratio IN2+, 391/IN2, 337 method are violated. In the glow discharge, N2 dissociation degree reaches about 7% with the argon

Denton E-beam Evaporator #1

Data.gov (United States)

Federal Laboratory Consortium — Description:CORAL Name: E-Beam Evap 1This is a dual e-beam/thermal evaporator for the deposition of metal and dielectric thin films. Materials available are: Ag, Al,...

Anticipated Guilt for not Helping and Anticipated Warm Glow for Helping are Differently Impacted by Personal Responsibility to Help

Directory of Open Access Journals (Sweden)

Arvid Erlandsson

2016-09-01

Full Text Available One important motivation for people behaving prosocially is that they want to avoid negative and obtain positive emotions. In the prosocial behavior literature however, the motivations to avoid negative emotions (e.g. guilt and to approach positive emotions (e.g. warm glow are rarely separated, and sometimes even aggregated into a single mood-management construct. The aim of this study was to investigate whether anticipated guilt if not helping and anticipated warm glow if helping are influenced similarly or differently when varying situational factors related to personal responsibility to help. Helping scenarios were created and pilot tests established that each helping scenario could be formulated both in a high-responsibility version and in a low-responsibility version. In Study 1 participants read high-responsibility and low-responsibility helping scenarios, and rated either their anticipated guilt if not helping or their anticipated warm glow if helping (i.e. separate evaluation. Study 2 was similar but here participants rated both their anticipated guilt if not helping and their anticipated warm glow if helping (i.e. joint evaluation. Anticipated guilt was clearly higher in the high-responsibility versions, but anticipated warm glow was unaffected (in Studies 1a and 1b, or even higher in the low-responsibility versions (Study 2. In Studies 3 (where anticipated guilt and warm glow were evaluated separately and 4 (where they were evaluated jointly, personal responsibility to help was manipulated within-subjects. Anticipated guilt was again constantly higher in the high-responsibility versions but for many types of responsibility-manipulations, anticipated warm glow was higher in the low-responsibility versions. The results suggest that we anticipate guilt if not fulfilling our responsibility but that we anticipate warm glow primarily when doing over and beyond our responsibility. We argue that future studies investigating motivations for

Anticipated Guilt for Not Helping and Anticipated Warm Glow for Helping Are Differently Impacted by Personal Responsibility to Help

Science.gov (United States)

Erlandsson, Arvid; Jungstrand, Amanda Å.; Västfjäll, Daniel

2016-01-01

One important motivation for people behaving prosocially is that they want to avoid negative and obtain positive emotions. In the prosocial behavior literature however, the motivations to avoid negative emotions (e.g., guilt) and to approach positive emotions (e.g., warm glow) are rarely separated, and sometimes even aggregated into a single mood-management construct. The aim of this study was to investigate whether anticipated guilt if not helping and anticipated warm glow if helping are influenced similarly or differently when varying situational factors related to personal responsibility to help. Helping scenarios were created and pilot tests established that each helping scenario could be formulated both in a high-responsibility version and in a low-responsibility version. In Study 1 participants read high-responsibility and low-responsibility helping scenarios, and rated either their anticipated guilt if not helping or their anticipated warm glow if helping (i.e., separate evaluation). Study 2 was similar but here participants rated both their anticipated guilt if not helping and their anticipated warm glow if helping (i.e., joint evaluation). Anticipated guilt was clearly higher in the high-responsibility versions, but anticipated warm glow was unaffected (in Studies 1a and 1b), or even higher in the low-responsibility versions (Study 2). In Studies 3 (where anticipated guilt and warm glow were evaluated separately) and 4 (where they were evaluated jointly), personal responsibility to help was manipulated within-subjects. Anticipated guilt was again constantly higher in the high-responsibility versions but for many types of responsibility-manipulations, anticipated warm glow was higher in the low-responsibility versions. The results suggest that we anticipate guilt if not fulfilling our responsibility but that we anticipate warm glow primarily when doing over and beyond our responsibility. We argue that future studies investigating motivations for helping

Successful Beam-Beam Tuneshift Compensation

Energy Technology Data Exchange (ETDEWEB)

Bishofberger, Kip Aaron [Univ. of California, Los Angeles, CA (United States)

2005-01-01

The performance of synchrotron colliders has been limited by the beam-beam limit, a maximum tuneshift that colliding bunches could sustain. Due to bunch-to-bunch tune variation and intra-bunch tune spread, larger tuneshifts produce severe emittance growth. Breaking through this constraint has been viewed as impossible for several decades. This dissertation introduces the physics of ultra-relativistic synchrotrons and low-energy electron beams, with emphasis placed on the limits of the Tevatron and the needs of a tuneshift-compensation device. A detailed analysis of the Tevatron Electron Lens (T_EL) is given, comparing theoretical models to experimental data whenever possible. Finally, results of Tevatron operations with inclusion of the T_EL are presented and analyzed. It is shown that the T_EL provides a way to shatter the previously inescapable beam-beam limit.

tgcd: An R package for analyzing thermoluminescence glow curves

Directory of Open Access Journals (Sweden)

Jun Peng

2016-01-01

Full Text Available Thermoluminescence (TL glow curves are widely used in dosimetric studies. Many commercial and free-distributed programs are used to deconvolute TL glow curves. This study introduces an open-source R package tgcd to conduct TL glow curve analysis, such as kinetic parameter estimation, glow peak simulation, and peak shape analysis. TL glow curves can be deconvoluted according to the general-order empirical expression or the semi-analytical expression derived from the one trap-one recombination center (OTOR model based on the Lambert W function by using a modified Levenberg–Marquardt algorithm from which any of the parameters can be constrained or fixed. The package provides an interactive environment to initialize parameters and offers an automated “trial-and-error” protocol to obtain optimal fit results. First-order, second-order, and general-order glow peaks (curves are simulated according to a number of simple kinetic models. The package was developed using a combination of Fortran and R programming languages to improve efficiency and flexibility.

Numerical analysis of thermoluminescence glow curves

International Nuclear Information System (INIS)

Gomez Ros, J. M.; Delgado, A.

1989-01-01

This report presents a method for the numerical analysis of complex thermoluminescence glow curves resolving the individual glow peak components. The method employs first order kinetics analytical expressions and is based In a Marquart-Levenberg minimization procedure. A simplified version of this method for thermoluminescence dosimetry (TLD) is also described and specifically developed to operate whit Lithium Fluoride TLD-100. (Author). 36 refs

Multiplicity detector using a glow-discharge memory

International Nuclear Information System (INIS)

Mulera, T.; Elola, M.; Perez-Mendez, V.; Wiedenbeck, P.

1981-04-01

It has been proposed to eliminate the x-y cor relation ambiguities introduced by multiple tracks in a wire chamber by using the chamber itself as a memory. Hits in the chamber itself ignite glow discharges storing the x-y location of the hits in a correlated fashion. Glow ignition may be achieved by employing a multi-step avalanche chamber above a memory gap. Correlation is maintained during readout by successively pulsing each hit wire in one coordinate and sensing transmissions through glows in the other coordinate. Prototypes constructed by the authors are discussed along with the associated high voltage and readout systems

Temperature dependent electron transport and rate coefficient studies for e-beam-sustained diffuse gas discharge switching

International Nuclear Information System (INIS)

Carter, J.G.; Hunter, S.R.; Christophorou, L.G.

1987-01-01

Measurements of the electron drift velocity, w, attachment coefficient, eta/N/sub a/, and ionization coefficient, α/N, have been made in C 2 F 6 /Ar and C 2 F 6 /CH 4 gas mixtures at gas temperatures, T, of 300 and 500 0 K over the concentration range of 0.1 to 100% of the C 2 F 6 . These measurements are useful for modeling the expected behavior of repetitively operated electron-beam sustained diffuse gas discharge opening switches where gas temperatures within the switch are anticipated to rise several hundred degrees during switch operation

Beam-strahlung effects in e-p collider

International Nuclear Information System (INIS)

Cho, Y.

1982-09-01

The electromagnetic fields produced by one beam in an interaction point of a colliding-beam facility cause to the emission of synchrotron radiation by the other beam. This effect, the beam strahlung, for the e+e - colliders has been considered by several authors, and they have pointed out that the effect is very important consideration at very-high-energy e+e - colliders. At the first glance, the beam-strahlung effect can play an important role in the e-p collision due to the fact that the circulating currents in the collider are much higher than those of the e+e - machine. However the detailed study shows that is not the case because of the collision geometry involved. What follows in this note is the beam-strahlung derivations using the method previously used by Hofmann and Keil. The difference between this note and that of Hofman and Keil is that in the case of e+e - collider, equal mass particles are involved in the consideration and, in the e-p case, the electrons radiate and the protons provide the electromagnetic fields

Oxygen negative glow: reactive species and emissivity

International Nuclear Information System (INIS)

Sahli, Khaled

1991-01-01

This research thesis addresses the study of a specific type of oxygen plasma created by electron beams (1 keV, 20 mA/cm"2), negative glow of a luminescent discharge in abnormal regime. The objective is to test the qualities of this plasma as source of two 'active' species of oxygen (singlet molecular oxygen and atomic oxygen) which are useful in applications. The experiment mainly bears on the use of VUV (120 to 150 nm) absorption spectroscopy measurements of concentrations of these both species, and on the recording of plasma emissivity space profiles in the visible region (450 to 850 nm). It appears that low concentrations of singlet oxygen definitely exclude this type of discharge for iodine laser applications. On the contrary, concentrations measured for atomic oxygen show it is a good candidate for the oxidation of large surfaces by sheets of beams. The satisfying comparison of emissivity results with a published model confirm the prevailing role of fast electrons, and gives evidence of an important effect of temperature: temperature can reach 1000 K, and this is in agreement with the presented measurement [fr

Fit of second order thermoluminescence glow peaks using the logistic distribution function

International Nuclear Information System (INIS)

Pagonis, V.; Kitis, G.

2001-01-01

A new thermoluminescence glow curve deconvolution (GCD) function is introduced which accurately describes second order thermoluminescence (TL) curves. The logistic asymmetric (LA) statistical probability function is used with the function variables being the maximum peak intensity (I m ), the temperature of the maximum peak intensity (T m ) and the LA width parameter a 2 . An analytical expression is derived from which the activation energy E can be calculated as a function of T m and the LA width parameter a 2 with an accuracy of 2% or better. The accuracy of the fit was tested for E values ranging from 0.7 to 2.5 eV, for s values between 10 5 and 10 25 s -1 , and for trap occupation number n 0 /N between 1 and 10 -6 . The goodness of fit of the logistic asymmetric function is described by the Figure of Merit (FOM) which is found to be of the order of 10 -2 . Preliminary results show that the GCD described here can easily be extended to the description of general order TL glow curves by varying the asymmetry parameter of the logistic asymmetric function. It is concluded that the TL kinetic analysis of first, second and general order TL glow curves can be performed with high accuracy and speed by using commercially available statistical packages that incorporate the Weibull and logistic asymmetric functions. (author)

Atomic iodine production in a gas flow by decomposing methyl iodide in a dc glow discharge

International Nuclear Information System (INIS)

Mikheyev, P A; Shepelenko, A A; Voronov, A I; Kupryaev, Nikolai V

2002-01-01

The production of atomic iodine for an oxygen - iodine laser is studied by decomposing methyl iodide in a dc glow discharge in a vortex gas flow. The concentration of iodine atoms in discharge products was measured from the atomic iodine absorption of the radiation of a single-frequency tunable diode laser at a wavelength of 1.315 μm. Atomic iodine concentrations sufficient for the operation of an oxygen - iodine laser were obtained. The concentration of atomic iodine amounted to 3.6 x 10 15 cm -3 for a pressure of the carrying argon gas of 15 Torr. The discharge stabilisation by a vortex gas flow allowed the glow discharge to be sustained in a strongly electronegative halogen-containing gas mixture for pressures up to 20 Torr. (active media)

High electron beam dosimetry using ZrO2

International Nuclear Information System (INIS)

Lueza M, F.; Rivera M, T.; Azorin N, J.; Garcia H, M.

2009-10-01

This paper reports the experimental results of studying the thermoluminescent (Tl) properties of ZrO 2 powder embedded in polytetrafluorethylene (PTFE) exposed to high energy electron beam from linear accelerators (Linac). Structural and morphological characteristics were also reported. Irradiations were conducted using high energy electrons beams in the range from 2 to 18 MeV. Pellets of ZrO 2 +PTFE were produced using polycrystalline powder grown by the precipitation method. These pellets presented a Tl glow curve exhibiting an intense glow peak centered at around 235 C. Tl response as a function of high electron absorbed dose was linear in the range from 2 to 30 Gy. Repeatability determined by exposing a set of pellets repeatedly to the same electron absorbed dose was 0.5%. Fading along 30 days was about 50%. Then, results obtained in this study suggest than ZrO 2 +PTFE pellets could be used for high energy electron beam dosimetry provided fading correction is accounted for. (Author)

Identifying the warm glow effect in contingent valuation

NARCIS (Netherlands)

Nunes, P.A.L.D.; Schokkaert, E.

2003-01-01

This paper reports the results from a contingent valuation study designed to investigate the influence of warm glow in willingness to pay (WTP) responses. Interindividual differences in warm glow motivation are measured through a factor analysis, performed on a list of attitudinal items. The

Boundary Effect of Planar Glow Dielectric Barrier Discharge and Its Influence on the Discharge Structure

International Nuclear Information System (INIS)

Xu Shaowei; Li Lulu; Ouyang Jiting

2015-01-01

The dielectric barrier discharge (DBD) in the glow regime in neon has been investigated by experiment and two-dimensional (2D) fluid modeling. The discharge was carried out in a planar DBD system with segmented-electrodes driven by square-wave voltage. The results show that the glow DBD originates in the center of the electrode and expands outward to the electrode edge during each half cycle of the voltage, forming a radial structure. The discharge decays firstly in the inner area but sustains longer in the edge area, showing a reversed discharge area. The discharge cannot completely cover the entire electrode surface, but remains a border of non- or weak discharge. The fluid modeling shows a similar result in agreement with the experiments. The simulations indicate that the electric field in the edge area is distorted due to the boundary effect so that the electric field and charge distribution are different from that in the inner part. The distorted field reduces the longitudinal component near the edge and causes the local field to be lower than that in the center, and hence makes the discharge behindhand. It also induces a transverse field that makes the discharge extend radially outward to the edge. The boundary effect plays an important role in the glow DBD structure. (paper)

Investigation of beam self-polarization in the future e+e- circular collider

Science.gov (United States)

Gianfelice-Wendt, E.

2016-10-01

The use of resonant depolarization has been suggested for precise beam energy measurements (better than 100 keV) in the e+e- Future Circular Collider (FCC-e+e-) for Z and W W physics at 45 and 80 GeV beam energy respectively. Longitudinal beam polarization would benefit the Z peak physics program; however it is not essential and therefore it will be not investigated here. In this paper the possibility of self-polarized leptons is considered. Preliminary results of simulations in presence of quadrupole misalignments and beam position monitors (BPMs) errors for a simplified FCC-e+e- ring are presented.

I'm sexy and I glow it: female ornamentation in a nocturnal capital breeder.

Science.gov (United States)

Hopkins, Juhani; Baudry, Gautier; Candolin, Ulrika; Kaitala, Arja

2015-10-01

In many species, males rely on sexual ornaments to attract females. Females, by contrast, rarely produce ornaments. The glow-worm (Lampyris noctiluca) is an exception where wingless females glow to attract males that fly in search of females. However, little is known about the factors that promote the evolution of female ornaments in a sexual selection context. Here, we investigated if the female ornament of the glow-worm is a signal of fecundity used in male mate choice. In support of this, we found brightness to correlate with female fecundity, and males to prefer brighter dummy females. Thus, the glow emitted by females is a reliable sexual signal of female fecundity. It is likely that male preference for the fecundity-indicating ornament has evolved because of large variation among females in fecundity, and because nocturnal males cannot directly assess female size and fecundity. These results indicate that female ornamentation may evolve in capital breeders (i.e. those in which stored resources are invested in reproduction) when females vary significantly in fecundity and this variation cannot be assessed directly by males. © 2015 The Author(s).

Pulsed glow discharge mass spectrometry for molecular depth profiling of polymers

International Nuclear Information System (INIS)

Lobo, L.; Pereiro, R.; Sanz-Medel, A.; Bordel, N.; Pisonero, J.; Licciardello, A.; Tuccitto, N.; Tempez, A.; Chapon, P.

2009-01-01

Full text: Nowadays thin films of polymeric materials involve a wide range of industrial applications, so techniques capable of providing in-depth profile information are required. Most of the techniques available for this purpose are based on the use of energetic particle beams which interact with polymers producing undesirable physicochemical modifications. Radiofrequency pulsed glow discharge (rf-pulsed-GD) coupled to time-of-flight mass spectrometry (TOFMS) could afford the possibility of acquiring both elemental and molecular information creating minimal damage to surfaces and thereby obtaining depth profiles. This work will evaluate rf-GDs coupled to an orthogonal TOFMS for direct analysis of polymers. (author)

Investigation of beam self-polarization in the future e^{+}e^{-} circular collider

Directory of Open Access Journals (Sweden)

E. Gianfelice-Wendt

2016-10-01

Full Text Available The use of resonant depolarization has been suggested for precise beam energy measurements (better than 100 keV in the e^{+}e^{-} Future Circular Collider (FCC-e^{+}e^{-} for Z and WW physics at 45 and 80 GeV beam energy respectively. Longitudinal beam polarization would benefit the Z peak physics program; however it is not essential and therefore it will be not investigated here. In this paper the possibility of self-polarized leptons is considered. Preliminary results of simulations in presence of quadrupole misalignments and beam position monitors (BPMs errors for a simplified FCC-e^{+}e^{-} ring are presented.

Sustaining neutral beam power supply system for the Mirror Fusion Test Facility

International Nuclear Information System (INIS)

Eckard, R.D.; Van Ness, H.W.

1979-01-01

A fixed-price procurement contract for $24.9 million was awarded to Aydin Energy Division, Palo Alto, CA, for the design, manufacture, installation, and acceptance testing of the sustaining neutral beam power supply system (SNBPSS). This system is scheduled for completion in early 1981 and will provide the conditioned power for the 24 neutral beam source modules. Each of the 24 power supply sets will provide the accel potential of 80 kV at 88 A, the arc power, the filament power, and the suppressor power for its associated neutral beam source module

Beam-beam effects in high energy e+e- storage rings: resonant amplification of vertical dimensions for flat beams

International Nuclear Information System (INIS)

Bambade, P.

1984-06-01

In this thesis, we present a phenomenological study of the beam-beam effect in e + e - storage rings. We are in particular interested in the blow-up of the vertical dimension observed in this kind of accelerator. A detailed analysis of the electromagnetic field generated by the very flat bunches stored, and seen by the counter-rotating particles shows that two-dimensional non-linear resonances, which couple vertical and horizontal betatron oscillations, play a very important role. Moreover, the ''weak beam-strong beam'' approximation holds rather well in the case of very flat bunches. Perturbative analysis enables us to predict the effects from the strongest coupling resonance: 20sub(x)-20sub(y) = integer. We find that mainly the tails of the vertical distribution are affected, and we give a criterion concerning the optimal distance to this resonance in the case of a storage ring such as LEP. Finally, the results and in particular the validity of the single resonance approximation are checked through a numerical simulation [fr

Laser ablation/ionization studies in a glow discharge

International Nuclear Information System (INIS)

Hess, K.R.; Harrison, W.W.

1985-01-01

The pin cathode glow discharge is used in the laboratory as an atomization/ionization source for a variety of applications, including solids mass spectrometry. Coupled with a tunable dye laser, the glow discharge may also serve as an atom reservoir for resonance ionization mass spectrometry in which the laser ionizes the discharge sputtered atoms. By tightly focusing the laser onto solid samples, various ablation effects may also be investigated. The laser may be used to generate an ionized plasma which may be directly analyzed by mass spectrometry. Alternatively, the ablated neutral atoms may be used in post-ablation excitation/ionization processes, in this case the glow discharge. The results of these investigations are the basis of this paper

TLD-100 glow-curve deconvolution for the evaluation of the thermal stress and radiation damage effects

CERN Document Server

Sabini, M G; Cuttone, G; Guasti, A; Mazzocchi, S; Raffaele, L

2002-01-01

In this work, the dose response of TLD-100 dosimeters has been studied in a 62 MeV clinical proton beams. The signal versus dose curve has been compared with the one measured in a sup 6 sup 0 Co beam. Different experiments have been performed in order to observe the thermal stress and the radiation damage effects on the detector sensitivity. A LET dependence of the TL response has been observed. In order to get a physical interpretation of these effects, a computerised glow-curve deconvolution has been employed. The results of all the performed experiments and deconvolutions are extensively reported, and the TLD-100 possible fields of application in the clinical proton dosimetry are discussed.

Beam-beam limit in e+e- circular colliders

International Nuclear Information System (INIS)

Ohmi, K.; Tawada, M.; Kamada, S.; Oide, K.; Cai, Y.; Qiang, J.

2004-01-01

Beam-beam effects limit the luminosity of circular colliders. Once the bunch population exceeds a threshold, the luminosity increases at a slower rate. This phenomenon is called the beam-beam limit. Onset of the beam-beam limit has been analyzed with various simulation methods based on the weak-strong and strong-strong models. We have observed that an incoherent phenomenon is mainly concerned in the beam-beam limit. The simulation have shown that equilibrium distributions of the two colliding beams are distorted from Gaussians when the luminosity is limited. The beam-beam limit is estimated to be ξ∼0.1 for a B factory with damping time of several thousand turns

Laser diagnostics for picosecond e-beams

International Nuclear Information System (INIS)

Pogorelsky, I.; Ben-Zvi, I.

1992-01-01

We propose a novel approach to picosecond e-bunch/laser pulse synchronization and spatial alignment based upon refraction and reflection of a laser beam on a plasma column created by relativistic electrons traveling through a gas or solid optical material. The technique may be used in laser accelerators and for general subpicosecond e-beam diagnostics

On the analysis of glow curves with the general order kinetics: Reliability of the computed trap parameters

Energy Technology Data Exchange (ETDEWEB)

Ortega, F. [Facultad de Ingeniería (UNCPBA) and CIFICEN (UNCPBA – CICPBA – CONICET), Av. del Valle 5737, 7400 Olavarría (Argentina); Santiago, M.; Martinez, N.; Marcazzó, J.; Molina, P.; Caselli, E. [Instituto de Física Arroyo Seco (UNCPBA) and CIFICEN (UNCPBA – CICPBA – CONICET), Pinto 399, 7000 Tandil (Argentina)

2017-04-15

Nowadays the most employed kinetics for analyzing glow curves is the general order kinetics (GO) proposed by C. E. May and J. A. Partridge. As shown in many articles this kinetics might yield wrong parameters characterizing trap and recombination centers. In this article this kinetics is compared with the modified general order kinetics put forward by M. S. Rasheedy by analyzing synthetic glow curves. The results show that the modified kinetics gives parameters, which are more accurate than that yield by the original general order kinetics. A criterion is reported to evaluate the accuracy of the trap parameters found by deconvolving glow curves. This criterion was employed to assess the reliability of the trap parameters of the YVO{sub 4}: Eu{sup 3+} compounds.

Beam-beam interaction in e+-e- storage rings

International Nuclear Information System (INIS)

Le Duff, J.

1977-01-01

Colliding beams in electron-positron storage rings are discussed with particular reference to the space charge forces occuring during beam-beam interactions and their effect on beam current and consequently machine performance (maximum luminosity). The first section deals with linear beam-beam effects and discussses linear tune shift; the second section considers non-linear beam-beam effects and the creation on non-linear resonances. The last section poses questions of the possibility of extrapolating present results to future machines and discusses optimization of storage ring performance. (B.D.)

Dissolution glow curve in LLD

International Nuclear Information System (INIS)

Haverkamp, U.; Wiezorek, C.; Poetter, R.

1990-01-01

Lyoluminescence dosimetry is based upon light emission during dissolution of previously irradiated dosimetric materials. The lyoluminescence signal is expressed in the dissolution glow curve. These curves begin, depending on the dissolution system, with a high peak followed by an exponentially decreasing intensity. System parameters that influence the graph of the dissolution glow curve, are, for example, injection speed, temperature and pH value of the solution and the design of the dissolution cell. The initial peak does not significantly correlate with the absorbed dose, it is mainly an effect of the injection. The decay of the curve consists of two exponential components: one fast and one slow. The components depend on the absorbed dose and the dosimetric materials used. In particular, the slow component correlates with the absorbed dose. In contrast to the fast component the argument of the exponential function of the slow component is independent of the dosimetric materials investigated: trehalose, glucose and mannitol. The maximum value, following the peak of the curve, and the integral light output are a measure of the absorbed dose. The reason for the different light outputs of various dosimetric materials after irradiation with the same dose is the differing solubility. The character of the dissolution glow curves is the same following irradiation with photons, electrons or neutrons. (author)

The breakdown and glow phases during the initiation of discharges for lamps

International Nuclear Information System (INIS)

Pitchford, L.C.; Peres, I.; Liland, K.B.; Boeuf, J.P.; Gielen, H.

1997-01-01

High intensity discharge (HID) lamps are often initiated by the application of one or more short, high-voltage, breakdown pulses superimposed on a 50 or 60 Hz generator voltage. A successful transition from the breakdown event to steady-state operating conditions in HID lamps requires that the lamp-circuit system be adequate to sustain the plasma created during breakdown until the electrodes are heated to thermionic temperatures. In this article, we use a one-dimensional (in the axial direction) transient discharge model to study the conditions needed to sustain the cold-cathode discharge after a breakdown event has occurred. While the application of our one-dimensional model to real lamps is approximate, we find that the model predictions are consistent with experimental results in HID lamps, a few of which are presented here. The main conclusion from this work is that, after breakdown, the voltage necessary to sustain a glow discharge is dependent on the source impedance, the gas composition, and on the plasma density created by the breakdown event. copyright 1997 American Institute of Physics

[The glow discharge as an atomization and ionization source

International Nuclear Information System (INIS)

1990-01-01

This is to summarize the research progress in this project at the University of Florida over the past 13 months. In keeping with the directions of the Federal Demonstration Project, the report will be brief, presenting an overview of the major findings. We have continued the study of the glow discharge, primarily as an ionization source for elemental analysis. Glow discharge interest continues to grow in the analytical chemistry community as evidenced by the number of special symposia at major conferences, by the new researchers entering the field, and by the introduction of new instrumentation. There is little doubt that glow discharge mass spectrometry, for example, is now a major technique in the elemental analysis of solids

Investigation of Gas Heating by Nanosecond Repetitively Pulsed Glow Discharges Used for Actuation of a Laminar Methane-Air Flame

KAUST Repository

Lacoste, Deanna

2017-05-24

This paper reports on the quantification of the heating induced by nanosecond repetitively pulsed (NRP) glow discharges on a lean premixed methane-air flame. The flame, obtained at room temperature and atmospheric pressure, has an M-shape morphology. The equivalence ratio is 0.95 and the thermal power released by the flame is 113 W. The NRP glow discharges are produced by high voltage pulses of 10 ns duration, 7 kV amplitude, applied at a repetition frequency of 10 kHz. The average power of the plasma, determined from current and voltage measurements, is 1 W, i.e. about 0.9 % of the thermal power of the flame. Broadband vibrational coherent anti-Stokes Raman spectroscopy of nitrogen is used to determine the temperature of the flame with and without plasma enhancement. The temperature evolution in the flame area shows that the thermal impact of NRP glow discharges is in the uncertainty range of the technique, i.e., +/- 40 K.

Surface modification of austenitic steel by various glow-discharge nitriding methods

Directory of Open Access Journals (Sweden)

Tomasz Borowski

2015-09-01

Full Text Available Recent years have seen intensive research on modifying glow-discharge nitriding processes. One of the most commonly used glow-discharge methods includes cathodic potential nitriding (conventional method, and active screen plasma nitriding. Each of these methods has a number of advantages. One very important, common feature of these techniques is full control of the microstructure, chemical and phase composition, thickness and the surface topography of the layers formed. Another advantage includes the possibility of nitriding such materials as: austenitic steels or nickel alloys, i.e. metallic materials which do not diffuse nitrogen as effectively as ferritic or martensitic steels. However, these methods have some disadvantages as well. In the case of conventional plasma nitriding, engineers have to deal with the edge effect, which makes it difficult to use this method for complexly shaped components. In turn, in the case of active screen plasma nitriding, the problem disappears. A uniform, smooth layer forms, but is thinner, softer and is not as resistant to friction compared to layers formed using the conventional method. Research is also underway to combine these methods, i.e. use an active screen in conventional plasma nitriding at cathodic potential. However, there is a lack of comprehensive data presenting a comparison between these three nitriding processes and the impact of pulsating current on the formation of the microstructure and functional properties of austenitic steel surfaces. The article presents a characterisation of nitrided layers produced on austenitic X2CrNiMo17-12-2 (AISI 316L stainless steel in the course of glow-discharge nitriding at cathodic potential, at plasma potential and at cathodic potential incorporating an active screen. All processes were carried out at 440 °C under DC glow-discharge conditions and in 100 kHz frequency pulsating current. The layers were examined in terms of their microstructure, phase and

Combustion aided by a glow plug in diesel engines under cold idling conditions

OpenAIRE

Li, Qile

2016-01-01

Glow plugs are widely used to promote the desired cold start and post-cold start combustion characteristics of light duty diesel engines. The importance of the glow plug becomes more apparent when the compression ratio is low. An experimental investigation of combustion initiation and development aided by the glow plug has been carried out on a single cylinder HPCR DI diesel engine with a low compression ratio of 15.5:1. High speed imaging of combustion initiated by the glow plug in a combust...

Means of introducing an analyte into liquid sampling atmospheric pressure glow discharge

Science.gov (United States)

Marcus, R. Kenneth; Quarles, Jr., Charles Derrick; Russo, Richard E.; Koppenaal, David W.; Barinaga, Charles J.; Carado, Anthony J.

2017-01-03

A liquid sampling, atmospheric pressure, glow discharge (LS-APGD) device as well as systems that incorporate the device and methods for using the device and systems are described. The LS-APGD includes a hollow capillary for delivering an electrolyte solution to a glow discharge space. The device also includes a counter electrode in the form of a second hollow capillary that can deliver the analyte into the glow discharge space. A voltage across the electrolyte solution and the counter electrode creates the microplasma within the glow discharge space that interacts with the analyte to move it to a higher energy state (vaporization, excitation, and/or ionization of the analyte).

E-waste: A Challenge for Sustainable Development

Directory of Open Access Journals (Sweden)

Md. Sahadat Hossain

2015-01-01

Conclusions. Sustainability is being prioritized for all development activities by integrating societal, economic, environmental, technological, cultural, and gender perspectives. Considering the adverse potential eco-toxicological impacts and diverse health effects of e-waste, an urgent global multilateral agreement is needed addressing its management (i.e., handling, storage, transportation, recycling, and final disposal, whether by land filling or incineration. Due to the global nature of the issue and the difficulty of establishing sustainable and environmentally sound processing of e-waste in low-income countries, multinational negotiation and collaboration is the only realistic solution. Furthermore, comprehensive global e-waste management and policies could help to off-set the hazards of e-waste and are the best approach for achieving sustainable development.

Analytical investigations of thermoluminescence glow curve on quartz for luminescence dating

International Nuclear Information System (INIS)

Kim, K.B.; Hong, D.G.

2015-01-01

Investigations of bleaching and thermoluminescence (TL) response to radiation dose of quartz are importance in luminescence dating. Although such research has been extensively carried out for various types of quartz, most work was performed on the basis of TL intensity integrated for a particular temperature range on the glow curve, without any peak separation. In this study we investigated bleaching by a blue light stimulation and radiation dose behaviour for separated TL glow peaks of quartz, which are thermally stable, by using the computerized glow curve deconvolution (CGCD) method combined with the T_m–T_s_t_o_p method. The T_m–T_s_t_o_p method indicates that the glow curve of quartz is the superposition of at least seven components (P1–P7) in the temperature range between room temperature and 450 °C. A bleaching experiment for four thermally stable glow peaks (P4–P7) using a blue light stimulation revealed that the bleaching rate of peak P4 exhibits three different exponential decays, whereas the peaks P5, P6 and P7 are bleached with two different exponential decays. After bleaching of 12 h, the TL intensity of peaks P4, P5, P6 and P7 were reduced to approximately 6%, 16%, 26% and 68% of the initial value, respectively. Additionally, in a study of the radiation dose response of the four thermally stable glow peaks, all peaks have a similar pattern, which are well fitted by a single saturating exponential function. - Highlights: • We studied the physical characteristics of the separated TL glow peaks on quartz. • The kinetic parameters of each separated glow peak are evaluated by a CGCD method. • The separated peaks were bleached with two or three exponential decays. • The dose responses for the separated peaks showed a similar growth curve.

Reply to comments on-The effect of the heating rate on the characteristics of some experimental thermoluminescence glow curves by Rasheedy et al

International Nuclear Information System (INIS)

Rasheedy, M S; Zahran, E M

2006-01-01

In the paper by Kumar et al, some criticism is advanced to the analysis of the glow curves measured under different heating rates in the laboratory, which appeared in our recent paper [M.S. Rasheedy and E.M. Zahran, 2006 Phys. Scr., 73 98-102]. According to this analysis the area under the glow curve is conserved in both TL-time plots and TL-temperature plots. On the contrary, Kumar et al supposed increase of the area under the glow curve with increasing the heating rate in the case of TL-temperature plots. Since this criticism discredits a physical reason for conservation of the area under the glow curves due to conservation of the imparted dose at different heating rates, a reply appears to be timely

Fuel hydrogen retention of tungsten and the reduction by inert gas glow discharges

Energy Technology Data Exchange (ETDEWEB)

Hino, T., E-mail: tomhino@qe.eng.hokudai.ac.jp [Laboratory of Plasma Physics and Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Yamauchi, Y.; Kimura, Y. [Laboratory of Plasma Physics and Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Nishimura, K. [National Institute for Fusion Science, Toki-shi, Gifu-ken 509-5292 (Japan); Ueda, Y. [Graduate School of Engineering, Osaka University, Suita-shi 565-0872 (Japan)

2012-08-15

Highlights: Black-Right-Pointing-Pointer The performances of inert gas glow discharges for reduction of fuel hydrogen retention in tungsten were systematically investigated. Black-Right-Pointing-Pointer For the tungsten with rough surface structure, the reduction of fuel hydrogen retention by inert gas discharges is quite small. Black-Right-Pointing-Pointer The deuterium glow discharge is quite useful to reduce the tritium retention in plasma facing walls in fusion reactor. Black-Right-Pointing-Pointer The wall baking with temperature higher than 700-800 K is also useful to reduce the tritium retention in plasma facing walls. - Abstract: Polycrystalline tungsten was exposed to deuterium glow discharge followed by He, Ne or Ar glow discharge. The amount of retained deuterium in the tungsten was measured using residual gas analysis. The amount of desorbed deuterium during the inert gas glow discharge was also measured. The amount of retained deuterium was 2-3 times larger compared with a case of stainless steel. The ratios of desorbed amount of deuterium by He, Ne and Ar glow discharges were 4.6, 3.1 and 2.9%, respectively. These values were one order of magnitude smaller compared with the case of stainless steel. The inert gas glow discharge is not suitable to reduce the fuel hydrogen retention for tungsten walls. However, the wall baking with a temperature higher than 700 K is suitable to reduce the fuel hydrogen retention. It is also shown that the use of deuterium glow discharge is effective to reduce the in-vessel tritium inventory in fusion reactors through the hydrogen isotope exchange.

Long pulse, plasma cathode E-gun

International Nuclear Information System (INIS)

Goebel, D.M.; Schumacher, R.W.; Watkins, R.M.

1993-01-01

A unique, long-pulse E-gun has been developed for high-power tube applications. The Hollow-Cathode-Plasma (HCP) E-gun overcomes the limitations of conventional thermionic-cathode guns that have limited current density (typically ≤ 10 A/cm 2 ) or field-emission guns that offer high current density but suffer from short pulsewidth capability (typically 50 A/cm 2 ), long-pulse operation without gap closure, and also requires no cathode-heater power. The gun employs a low-pressure glow discharge inside a hollow cathode (HC) structure to provide a stable, uniform plasma surface from which a high current-density electron beam can be extracted. The plasma density is controlled by a low-voltage HC discharge pulser to produce the desired electron current density at the first grid of a multi-grid accelerator system. A dc high-voltage electron-beam supply accelerates the electrons across the gap, while the HC pulser modulates the beam current to generate arbitrary pulse waveforms. The electron accelerator utilizes a multi-aperture array that produces a large area, high perveance (>35 μpervs) beam consisting initially of many individual beamlets. The E-beam is normally operated without an applied magnetic field in the ion-focused regime, where the plasma produced by beam ionization of a background gas space-charge neutralizes the beam, and the Bennett self-pinch compresses the beamlets and increases the current density. The self-pinched beam has been observed to propagate over a meter without beam breakup or instabilities. The HCP E-gun has been operated at voltages up to 150 kV, currents up to 750 A, and pulse lengths of up to 120 μsec

Target surface condition during reactive glow discharge sputtering of copper

International Nuclear Information System (INIS)

Depla, D; Haemers, J; Gryse, R De

2002-01-01

During reactive glow discharge sputtering of copper in an argon/nitrogen plasma, we noticed an abrupt change of the target voltage and the deposition rate when the nitrogen concentration in the plasma exceeds a critical value. To explain this behaviour, the target surface after reactive glow discharge sputtering was examined by x-ray photoelectron spectroscopy (XPS). An experimental arrangement was constructed that allows direct transfer of the glow discharge cathode to the XPS analysis chamber without air exposure. These XPS measurements revealed that several different chemical states of nitrogen are present in the layer that forms on the target surface. The relative concentration of these different states changes when the critical nitrogen concentration in the plasma is exceeded

Thermoluminescence properties of Al2O3:Tb nanoparticles irradiated by gamma rays and 85 MeV C6+ ion beam

International Nuclear Information System (INIS)

Salah, Numan; Alharbi, Najlaa D.; Habib, Sami S.; Lochab, S.P.

2015-01-01

Carbon ions beam is recently recognized as an ideal cancer treatment modality, because of its excellent local tumor control. These ions have a high relative biological effectiveness resulting from high linear energy transfer (LET) and their sharp Bragg peak. However, the dose of those energetic ions needs to be measured with great precision using a proper dosimeter. Aluminum Oxide (Al 2 O 3 ) is a highly luminescent phosphor widely used for radiation dosimetry using thermoluminesence (TL) technique. In this work nanoparticles of this material activated by different elements like Eu, Tb, Dy, Cu and Ag were evaluated for their TL response to gamma rays irradiation. Tb doped sample is found to be the most sensitive sample, which could be selected for exposure to 85 MeV C 6+ ion beam in the fluence range 10 9 –10 13 ions/cm 2 . The obtained result shows that C ion beam irradiated sample has a simple glow curve structure with a prominent glow peak at around 230 °C. This glow curve has a dosimetric peak better than those induced by gamma rays. This glow peak exhibits a linear response in the range 10 9 –10 11 ions/cm 2 , corresponding to the equivalent absorbed doses 0.285–28.5 kGy. The absorbed doses, penetration depths and main energy loss were calculated using TRIM code based on the Monte Carlo simulation. The wide linear response of Al 2 O 3 :Tb nanoparticles along with the low fading makes this low cost nanomaterial a good candidate for C ion beam dosimetry. - Highlights: • Nanoparticles of Al 2 O 3 doped with Eu, Tb, Dy, Cu and Ag were synthesised. • They were evaluated for their TL response to gamma rays and C ion beam irradiation. • Tb doped sample is the most sensitive sample to gamma rays. • Al 2 O 3 :Tb was exposed to 85 MeV C 6+ ion beam in the fluence range 10 9 -10 13 ions/cm 2 . • The glow peak induced by C ions has a linear response in the range 10 9 -10 11 ions/cm 2

Hydrodynamic Expansion of Pellicles Caused by e-Beam Heating

CERN Document Server

Ho, D

2000-01-01

Placing a pellicle in front of a x-ray converter target for radiographic applications can confine the backstreaming ions and target plasma to a shorter channel so that the cumulative effect on e-beam focusing is reduced. The pellicle is subject to heating by e-beam since the pellicle is placed upstream of the target. The calculation of the hydrodynamic expansion, caused by the heating, using the radiation hydrodynamics code LASNEX is presented in this report. Calculations show that mylar pellicles disintegrate at the end of a multi-pulse intense e-beam while beryllium and carbon pellicles remain intact. The expansions for the kapton-carbon multi-layered targets are also examined. Hydrodynamic expansions for pellicles with various e-beam spot radii are calculated for DARHT-II beam parameters. All the simulation results indicate that the backstreaming ions can be stopped.

Transmission characteristics of microwave in a glow-discharge dusty plasma

Science.gov (United States)

Jia, Jieshu; Yuan, Chengxun; Gao, Ruilin; Liu, Sha; Yue, Feng; Wang, Ying; Zhou, Zhong-Xiang; Wu, Jian; Li, Hui

2016-07-01

In this study, the propagation characteristics of electromagnetic wave in a glow discharge plasma with dust particles are experimentally investigated. A helium alternating current glow discharge plasmas have been successfully generated. Measurements of the plasma parameters using Langmuir probes, in the absence of dust particles, provide plasma densities (ne) of 1017 m-3 and electron temperatures (Te) ranging from 2 to 4 eV. Dusty plasmas are made by adding 30 nm radius aluminum oxide (Al2O3) particles into the helium plasma. The density of the dust particle (nd) in the device is about 1011-1012 m-3. The propagation characteristics of electromagnetic waves are determined by a vector network analyzer with 4-6 GHz antennas. An apparent attenuation by the dust is observed, and the measured attenuation data are approximately in accordance with the theoretical calculations. The effects of gas pressure and input power on the propagation are also investigated. Results show that the transmission attenuation increases with the gas pressure and input power, the charged dust particles play a significant role in the microwave attenuation.

Glow curve characteristics of bulb type thermoluminescent dosimeters

International Nuclear Information System (INIS)

Deme, S.; Feher, I.; Felszerfalvi, J.

1993-01-01

TL dosemeter readers are equipped usually with thermocouples connected to the heater unit. This layout can well be applied to stabilize the position of the glow curve as a function of heating-up time. Bulb type TL dosemeters do not have temperature sensors, no possibility for stabilization, which can cause an additional readout error of dose determination. For this reason, the time dependence of glow curves for bulb-type TL dosemeters was measured, and a new microprocessor controlled readout device was developed. (N.T.) 2 refs.; 2 figs

Fast and Precise Beam Energy Measurement using Compton Backscattering at e+e- Colliders

CERN Document Server

Kaminskiy, V V; Muchnoi, N Yu; Zhilich, V N

2017-01-01

The report describes a method for a fast and precise beam energy measurement in the beam energy range 0.5-2 GeV and its application at various e+e- colliders. Low-energy laser photons interact head-on with the electron or positron beam and produce Compton backscattered photons whose energy is precisely measured by HPGe detector. The method allows measuring the beam energy with relative accuracy of ∼2-5.10-5. The method was successfully applied at VEPP-4M, VEPP-3, VEPP-2000 (BINP, Russia) and BEPC-II (IHEP, China).

A Study of Electron Decay in Nitrogen Time After-glow

International Nuclear Information System (INIS)

Veis, P.; Coitout, H.; Magne, L.; Cernogora, G.

1999-01-01

This paper deals with electron density measurements in nitrogen time after-glow using hyper frequency resonant cavity. The studied pressures are from the range 9-530 Pa and discharge currents from 20 mA up to 500 mA. Electrons decreases up to the time of 1,4 ms in after-glow depending on pressure, pulse current and pulse duration (Authors)

Glow experiment documentation of OMS/RCS pod and vertical stabilizer

Science.gov (United States)

1982-01-01

Glow experiment documentation of one of the orbital maneuvering system (OMS) reaction control system (RCS) pods and a portion of the vertical stabilizer shows chemoluminescent effectresulting from atomic oxygen impacting the spacecraft and building to the point that the atomic oxygen atoms combine to form molecules of oxygen. The Image Intensifier on NIKON 35mm camera was used to record the glow.

Glow experiment documentation of OMS/RCS pods and vertical stabilizer

Science.gov (United States)

1982-01-01

Glow experiment documentation of orbital maneuvering system (OMS) reaction control system (RCS) pods and vertical stabilizer shows chemo-luminescent effect resulting from atomic oxygen impacting the spacecraft and building to the point that the atomic oxygen atoms combine to form molecules of oxygen. Image intensifier on NIKON 35mm camera was used to record glow on vertical tail and OMS pods.

A Framework for Discussing e-Research Infrastructure Sustainability

Directory of Open Access Journals (Sweden)

Daniel S Katz

2014-07-01

Full Text Available e-Research infrastructure is increasingly important in the conduct of science and engineering research, and in many disciplines has become an essential part of the research infrastructure. However, this e-Research infrastructure does not appear from a vacuum; it needs both intent and effort first to be created and then to be sustained over time. Research cultures and practices in many disciplines have not adapted to this new paradigm, due in part to the absence of a deep understanding of the elements of e-Research infrastructure and the characteristics that influence their sustainability. This paper outlines a set of contexts in which e-Research infrastructure can be discussed, proposes characteristics that must be considered to sustain infrastructure elements, and highlights models that may be used to create and sustain e-Research infrastructure. We invite feedback on the proposed characteristics and models presented herein.

Denton E-beam Evaporator #2

Data.gov (United States)

Federal Laboratory Consortium — Description:CORAL Name: E-Beam Evap 2This is an electron gun evaporator for the deposition of metals and dielectrics thin films. Materials available are: Ag, Al, Au,...

Sustaining neutral beam power supply system for the Mirror Fusion Test Facility

International Nuclear Information System (INIS)

Eckard, R.D.; Wilson, J.H.; Van Ness, H.W.

1980-01-01

In late August 1978, a fixed price procurement contract for $25,000,000 was awarded to Aydin Energy Division, Palo Alto, California, for the design, manufacture, installation and acceptance testing of the Lawrence Livermore National Laboratory Mirror Fusion Test Facility (MFTF) Sustaining Neutral Beam Power Supply System (SNBPSS). This system of 24 power supply sets will provide the conditioned power for the 24 neutral beam source modules. Each set will provide the accel potential the arc power, the filament power, and the suppressor power for its associated neutral beam source module. The design and development of the SNBPSS has progressed through the final design phase and is now in production. Testing of the major sub-assembly power supply is proceeding at Aydin and the final acceptance testing of the first two power supplies at LLNL is expected to be completed this year

Geometrical E-beam proximity correction for raster scan systems

Science.gov (United States)

Belic, Nikola; Eisenmann, Hans; Hartmann, Hans; Waas, Thomas

1999-04-01

High pattern fidelity is a basic requirement for the generation of masks containing sub micro structures and for direct writing. Increasing needs mainly emerging from OPC at mask level and x-ray lithography require a correction of the e-beam proximity effect. The most part of e-beam writers are raster scan system. This paper describes a new method for geometrical pattern correction in order to provide a correction solution for e-beam system that are not able to apply variable doses.

Determination of the plasma impedance of a glow discharge in carbon dioxide

Science.gov (United States)

Kiselev, A. S.; Smirnov, E. A.

2017-07-01

In this work an expression for the dynamic resistance of a glow discharge flowing in long tubes is obtained and analyzed. The expression describes the physical processes occurring in the positive column of a glow discharge. The frequency dependences of the active and reactive components as well as the dynamic resistance module for the discharge conditions corresponding to CO2-lasers have been calculated. Based on the simulation results developed a computer program in the C# programming language for modeling the dynamic resistance discharge of glow discharge lasers.

Construction of double discharge pulsed electron beam generator and its applications

International Nuclear Information System (INIS)

Goektas, H.

2001-12-01

Generation of fast pulsed electron beam by superposing DC and pulsed hollow cathode discharge is studied. The electrical characteristics and measurements of the electron beam generator are done dc glow discharge and for the pulsed one. The electron beam current, its density and magnetic field effect, pinch effect, have been studied. The dependence of the electron beam parameters with respect to pressure and magnetic field have been studied. The pulsing effect of the beam is reviewed. By using the generator, micron holes drilling and carbon deposition was done at the laboratory. As a target source for carbon deposition methane gas is used and for Hydrogen-free carbon deposition was graphite

[Automatic adjustment control system for DC glow discharge plasma source].

Science.gov (United States)

Wan, Zhen-zhen; Wang, Yong-qing; Li, Xiao-jia; Wang, Hai-zhou; Shi, Ning

2011-03-01

There are three important parameters in the DC glow discharge process, the discharge current, discharge voltage and argon pressure in discharge source. These parameters influence each other during glow discharge process. This paper presents an automatic control system for DC glow discharge plasma source. This system collects and controls discharge voltage automatically by adjusting discharge source pressure while the discharge current is constant in the glow discharge process. The design concept, circuit principle and control program of this automatic control system are described. The accuracy is improved by this automatic control system with the method of reducing the complex operations and manual control errors. This system enhances the control accuracy of glow discharge voltage, and reduces the time to reach discharge voltage stability. The glow discharge voltage stability test results with automatic control system are provided as well, the accuracy with automatic control system is better than 1% FS which is improved from 4% FS by manual control. Time to reach discharge voltage stability has been shortened to within 30 s by automatic control from more than 90 s by manual control. Standard samples like middle-low alloy steel and tin bronze have been tested by this automatic control system. The concentration analysis precision has been significantly improved. The RSDs of all the test result are better than 3.5%. In middle-low alloy steel standard sample, the RSD range of concentration test result of Ti, Co and Mn elements is reduced from 3.0%-4.3% by manual control to 1.7%-2.4% by automatic control, and that for S and Mo is also reduced from 5.2%-5.9% to 3.3%-3.5%. In tin bronze standard sample, the RSD range of Sn, Zn and Al elements is reduced from 2.6%-4.4% to 1.0%-2.4%, and that for Si, Ni and Fe is reduced from 6.6%-13.9% to 2.6%-3.5%. The test data is also shown in this paper.

Assessing the Warm Glow Effect in Contingent Valuations for Public Libraries

Science.gov (United States)

Lee, Soon-Jae; Chung, Hye-Kyung; Jung, Eun-Joo

2010-01-01

This article aims to present evidence of the warm glow effect in a public library setting. More specifically, it tests whether individual respondents with different values for the warm glow component report different values for their willingness to pay (WTP). The data come from a contingent valuation survey conducted on randomly selected citizens…

Effect of the interaction among traps on the shape of thermoluminescence glow curves

International Nuclear Information System (INIS)

Marcazzo, J.; Santiago, M.; Spano, F.; Lester, M.; Ortega, F.; Molina, P.; Caselli, E.

2007-01-01

The effect of the interaction among traps on the structure of thermoluminescence glow curves has been investigated by generating numerically simulated glow curves for a wide range of trap parameters. The results reported in this paper provide useful insights which assist in the analysis of experimental glow curves. The most important result shows that it is incorrect to assume beforehand that each peak is related to a specific trapping state. The validity of the quasiequilibrium approximation is briefly discussed

Simulation of nonstationary phenomena in atmospheric-pressure glow discharge

Science.gov (United States)

Korolev, Yu. D.; Frants, O. B.; Nekhoroshev, V. O.; Suslov, A. I.; Kas'yanov, V. S.; Shemyakin, I. A.; Bolotov, A. V.

2016-06-01

Nonstationary processes in atmospheric-pressure glow discharge manifest themselves in spontaneous transitions from the normal glow discharge into a spark. In the experiments, both so-called completed transitions in which a highly conductive constricted channel arises and incomplete transitions accompanied by the formation of a diffuse channel are observed. A model of the positive column of a discharge in air is elaborated that allows one to interpret specific features of the discharge both in the stationary stage and during its transition into a spark and makes it possible to calculate the characteristic oscillatory current waveforms for completed transitions into a spark and aperiodic ones for incomplete transitions. The calculated parameters of the positive column in the glow discharge mode agree well with experiment. Data on the densities of the most abundant species generated in the discharge (such as atomic oxygen, metastable nitrogen molecules, ozone, nitrogen oxides, and negative oxygen ions) are presented.

Simulation of nonstationary phenomena in atmospheric-pressure glow discharge

International Nuclear Information System (INIS)

Korolev, Yu. D.; Frants, O. B.; Nekhoroshev, V. O.; Suslov, A. I.; Kas’yanov, V. S.; Shemyakin, I. A.; Bolotov, A. V.

2016-01-01

Nonstationary processes in atmospheric-pressure glow discharge manifest themselves in spontaneous transitions from the normal glow discharge into a spark. In the experiments, both so-called completed transitions in which a highly conductive constricted channel arises and incomplete transitions accompanied by the formation of a diffuse channel are observed. A model of the positive column of a discharge in air is elaborated that allows one to interpret specific features of the discharge both in the stationary stage and during its transition into a spark and makes it possible to calculate the characteristic oscillatory current waveforms for completed transitions into a spark and aperiodic ones for incomplete transitions. The calculated parameters of the positive column in the glow discharge mode agree well with experiment. Data on the densities of the most abundant species generated in the discharge (such as atomic oxygen, metastable nitrogen molecules, ozone, nitrogen oxides, and negative oxygen ions) are presented.

Combined phenomena of beam-beam and beam-electron cloud interactionsin circular e^{+}e^{-} colliders

Directory of Open Access Journals (Sweden)

Kazuhito Ohmi

2002-10-01

Full Text Available An electron cloud causes various effects in high intensity positron storage rings. The positron beam and the electron cloud can be considered a typical two-stream system with a certain plasma frequency. Beam-beam interaction is another important effect for high luminosity circular colliders. Colliding two beams can be considered as a two-stream system with another plasma frequency. We study the combined phenomena of the beam-electron cloud and beam-beam interactions from a viewpoint of two complex two-stream effects with two plasma frequencies.

Detection of negative ions in glow discharge mass spectrometry for analysis of solid specimens

DEFF Research Database (Denmark)

Canulescu, Stela; Molchan, Igor S.; Tauziede, C.

2010-01-01

A new method is presented for elemental and molecular analysis of halogen-containing samples by glow discharge time-of-flight mass spectrometry, consisting of detection of negative ions from a pulsed RF glow discharge in argon. Analyte signals are mainly extracted from the afterglow regime...... be used to study the distribution of a tantalum fluoride layer within the anodized tantala layer. Further, comparison is made with data obtained using glow-discharge optical emission spectroscopy, where elemental fluorine can only be detected using a neon plasma. The ionization mechanisms responsible...... for the formation of negative ions in glow discharge time-of-flight mass spectrometry are briefly discussed....

Polarisation measurements on e sup+- beams

CERN Document Server

Long, K

2002-01-01

The current status of e sup+--beam polarimetry at the HERA ep collider is reviewed, giving the performance achieved to date and the status of the various upgrade projects together with a summary of the expected performance. In addition, the polarimeter that has been proposed for the TESLA e sup + e sup - collider is described.

Self-consistent model for pulsed direct-current N2 glow discharge

International Nuclear Information System (INIS)

Liu Chengsen

2005-01-01

A self-consistent analysis of a pulsed direct-current (DC) N 2 glow discharge is presented. The model is based on a numerical solution of the continuity equations for electron and ions coupled with Poisson's equation. The spatial-temporal variations of ionic and electronic densities and electric field are obtained. The electric field structure exhibits all the characteristic regions of a typical glow discharge (the cathode fall, the negative glow, and the positive column). Current-voltage characteristics of the discharge can be obtained from the model. The calculated current-voltage results using a constant secondary electron emission coefficient for the gas pressure 133.32 Pa are in reasonable agreement with experiment. (authors)

Electron beam extraction from a HVPES

International Nuclear Information System (INIS)

Marghitu, S.; Cramariuc, R.; Nicolescu, I.; Niculescu, M.

1996-01-01

The results of the research concerning the extraction system of the fast electrons from a cold cathode high voltage glow discharge plasma electron source (HVPES) are presented. For using the electron beam in a more flexible way, that is changing the shape of the minimum cross-section, (or beam cross-over), of the beam in a sample S frontal plane, without perturbing the discharge parameters, some modifications to a reference internal geometry were tested. Finally, a geometry was found in which the discharge volume may be separated in two parts, one, 'a discharge space', filled with plasma and fast electrons and another, 'working space', occupied specially by the fast electron beam. In this new geometry the electrical discharge parameters, I d - discharge current, U d - discharge voltage, were the same as for the reference geometry. (authors)

Propagation of ionizing waves in glow discharge

International Nuclear Information System (INIS)

Suzuki, T.

1977-01-01

Ionizing waves were produced along the positive column of a glow discharge in air by applying an impulse voltage to an electrode at one end of the column. Five photomultipliers and three current-sensing coils were used to observe how the waves were affected by the rise time and the magnitude of the applied impulses and by the electron density in the positive column of the glow discharge. It is shown that the speed of the ionizing waves increases with the slope of the applied impulses and with the preexisting electron density. The electron density is augmented about 100--200 times due to the buildup of ionization at the front of the waves. The theory was developed to explain the property of ionizing waves

Thermoluminescence characterization of isolated minerals to identify oranges exposed to γ-ray, e-beam, and X-ray for quarantine applications

International Nuclear Information System (INIS)

Deokjo Jo; Joong-Ho Kwon; Bhaskar Sanyal; Bhabha Atomic Research Centre, Mumbai; Ju-Woon Lee

2015-01-01

Identification of irradiated fruits is of paramount importance to address the limitation of irradiation technology because of varying national and international regulations. Thermoluminescence (TL) analysis was carried out to identify oranges irradiated with γ-ray, electron beam and X-ray. Non-irradiated samples exhibited background TL signals, but all the irradiated samples showed defined TL glow curves characterized by a prominent peak at 158-163 deg C. Characterizations of the irradiated standard minerals showed that feldspars were the major contributors to the TL emission and stable TL signals revealed a successful detection of irradiated oranges even after a prolonged storage. (author)

Sustained diffusive alternating current gliding arc discharge in atmospheric pressure air

Science.gov (United States)

Zhu, Jiajian; Gao, Jinlong; Li, Zhongshan; Ehn, Andreas; Aldén, Marcus; Larsson, Anders; Kusano, Yukihiro

2014-12-01

Rapid transition from glow discharge to thermal arc has been a common problem in generating stable high-power non-thermal plasmas especially at ambient conditions. A sustained diffusive gliding arc discharge was generated in a large volume in atmospheric pressure air, driven by an alternating current (AC) power source. The plasma column extended beyond the water-cooled stainless steel electrodes and was stabilized by matching the flow speed of the turbulent air jet with the rated output power. Comprehensive investigations were performed using high-speed movies measured over the plasma column, synchronized with simultaneously recorded current and voltage waveforms. Dynamic details of the novel non-equilibrium discharge are revealed, which is characterized by a sinusoidal current waveform with amplitude stabilized at around 200 mA intermediate between thermal arc and glow discharge, shedding light to the governing mechanism of the sustained spark-suppressed AC gliding arc discharge.

Advances in ion beam intensity at Sandia National Laboratories

International Nuclear Information System (INIS)

Mehlhorn, T.A.; Bailey, J.E.; Coats, R.S.

1995-01-01

In 1993 lithium beam intensities ≥1 TW/cm 2 were achieved and lithium-driven target experiments at the ∼1,400 TW/g level were performed on the Particle Beam Fusion Accelerator II (PBFA II) at Sandia National Laboratories. Hohlraum radiation temperatures of up to 60 eV were achieved using this lithium beam. The 1995 Light-Ion ICF Program milestone of achieving a 100 eV radiation temperature in an ion-driven hohlraum will require a lithium beam intensity of 5 ± 1 TW/cm 2 on a 4 mm diameter cylindrical target; this will require both an increase in coupled lithium power and a decrease in total lithium beam divergence. The lithium beam power has been limited to ∼5--6 TW by a so-called ''parasitic load.'' This parasitic current loss in the ion diodes has recently been identified as being carried by ions that are accelerated from plasmas that are formed when high voltage electrons are lost to anodes with many monolayers of hydrocarbon surface contamination. Control of anode and cathode plasmas on the SABRE accelerator using RF-discharge cleaning, anode heating, and cryogenic cooling of the cathode have increased the efficiency of the production of lithium current by a factor of 2--3. A new ion diode incorporating glow discharge cleaning and titanium gettering pumps has been installed in PBFA II and will be tested in December, 1994. Anode heaters should be available in January, 1995. Circuit model calculations indicate that one can more than double the coupled lithium ion power on PBFA II by eliminating the parasitic current. LiF source divergence presently dominates the total beam divergence. Progress in lithium beam focal intensity using diode cleaning techniques coupled with an active lithium source is reported

On the distribution of plasma parameters in RF glow discharge

International Nuclear Information System (INIS)

Ning Cheng; Liu Zuli; Liu Donghui; Han Caiyuan.

1993-01-01

A self-consistent numerical model based on the two-fluid equations for describing the transport of charged particles in the RF glow discharge is presented. For a plasma generator filled with low-pressure air and parallel-plate electrodes, the model is numerical solved. The space-time distribution of parameters and the spatial distribution of some time-averaged parameters in plasma, which show the physical picture of the RF glow discharge, are obtained

Effects of time-temperature profiles on glow curves of germanium-doped optical fibre

Science.gov (United States)

Lam, S. E.; Alawiah, A.; Bradley, D. A.; Mohd Noor, N.

2017-08-01

The Germanium (Ge) doped silica optical fibres have demonstrated the great potential to be developed as a thermoluminescent (TL) dosimeter that can be used in various applications in radiotherapy, diagnostic radiology, UV dosimetry system and food irradiation industry. Different time-temperature profile (TTP) parameters of the TL reader have been employed by many researchers in various of TL studies. Nevertheless, none of those studies adequately addressed the effects of the reader's preheat temperature and heating rate on the kinetic parameters of the TL glow curve specifically, the Ge-doped silica optical fibres. This research addresses the issue of TTP parameters with special attention to the determination of the kinetic parameters of the glow curve. The glow curve responses were explored and the kinetic parameters were analyzed by the WinGCF software, to show the effect of the preheat temperature and heating rate of the reader on Ge-doped fibre irradiated with 18 Gy of 6 MV photons radiation. The effect of TTP parameters was discussed and compared against the commercial fibre and tailored made fibre of 6 mol% Ge-doped of flat and cylindrical shape. The deconvolution of glow peaks and the kinetic parameters were obtained by the WinGCF software. This enables to fit accurately (1.5%glow curves. A positive, moderate linear relationship exists between the TL response and the heating rate when the specific preheat temperature was used to read commercial fibre (50 °C) and cylindrical fibre (80 °C and 160 °C). It is found that the glow peaks of cylindrical fibre exhibit the highest peak integral as compared to flat and commercial fibres. This study revealed the possible relationship between the reader's TTP parameters and the kinetic parameters of TL glow curves for the commercial and tailored made Ge-doped silica optical fibres.

TL glow curve analysis of UV, beta and gamma induced limestone collected from Amarnath holy cave

Directory of Open Access Journals (Sweden)

Vikas Dubey

2015-01-01

Full Text Available The paper reports themoluminescence glow curve analysis of UV (ultraviolet, β (beta and γ (gamma induced limestone collected from Amarnath holy cave. The collected natural sample was characterized by X-ray diffraction (XRD technique and crystallite size calculated by Scherer's formula. Surface morphology and particle size was calculated by transmission electron microscopy (TEM study. Effect of annealing temperature on collected lime stone examined by TL glow curve study. The limestone was irradiated by UV radiation (254 nm source and the TL glow curve recorded for different UV exposure time. For beta irradiation Sr90 source was used and is shows intense peak at 256 °C with a shoulder peak at higher temperature range. For gamma radiation Co60 source and TL glow curve recorded for different doses of gamma. The kinetic parameters calculation was performed for different glow curve by computerized glow curve deconvolution (CGCD technique. The chemical composition of natural limestone was analyzed by energy dispersive X-ray spectroscopy (EDXS.

Study of short atmospheric pressure dc glow microdischarge in air

Science.gov (United States)

Kudryavtsev, Anatoly; Bogdanov, Eugene; Chirtsov, Alexander; Emelin, Sergey

2011-10-01

The results of experiments and simulations of short (without positive column) atmospheric pressure dc glow discharge in air are presented. We used metal steel electrodes with a gap of 5-100 microns. The experimental voltage-current characteristic's (VAC) have a constant or slightly increasing form at low gap. The most stable microdischarges were burning with a flat cathode and rounded anode, when the length of the discharge is automatically established near the minimum of the Paschen curve by changing their binding on the anode. In this case microdischarge was stable and it had growing VAC. For simulations we used 2D fluid model with kinetic description of electrons. We solved the balance equations for the vibrationally- and the electronically-excited states of a nitrogen and oxygen molecules; nitrogen and oxygen atoms; ozone molecule; and different nitrogen and oxygen ions with different plasmochemical reactions between them. Simulations predicted the main regions of the dc glow discharges including cathode and anode sheath and plasma of negative glow, Faraday dark space and transition region. Gas heating plays an important role in shaping the discharge profiles. The results of experiments and simulations of short (without positive column) atmospheric pressure dc glow discharge in air are presented. We used metal steel electrodes with a gap of 5-100 microns. The experimental voltage-current characteristic's (VAC) have a constant or slightly increasing form at low gap. The most stable microdischarges were burning with a flat cathode and rounded anode, when the length of the discharge is automatically established near the minimum of the Paschen curve by changing their binding on the anode. In this case microdischarge was stable and it had growing VAC. For simulations we used 2D fluid model with kinetic description of electrons. We solved the balance equations for the vibrationally- and the electronically-excited states of a nitrogen and oxygen molecules; nitrogen

LHC main dipole magnet circuits: sustaining near-nominal beam energies

CERN Document Server

AUTHOR|(CDS)2085621; Auchmann, Bernhard; Knox, Andrew; O'Shea, Valentine

2016-11-04

Crossing the Franco-Swiss border, the Large Hadron Collider (LHC), designed to collide 7 TeV proton beams, is the world's largest and most powerful particle accelerator the operation of which was originally intended to commence in 2008. Unfortunately, due to an interconnect discontinuity in one of the main dipole circuit's 13 kA superconducting busbars, a catastrophic quench event occurred during initial magnet training, causing significant physical system damage. Furthermore, investigation into the cause found that such discontinuities were not only present in the circuit in question, but throughout the entire LHC. This prevented further magnet training and ultimately resulted in the maximum sustainable beam energy being limited to approximately half that of the design nominal, 3.5-4 TeV, for the first three years of operation (Run 1, 2009-2012) and a major consolidation campaign being scheduled for the first long shutdown (LS 1, 2012-2014). Throughout Run 1, a series of studies attempted to predict the amo...

Simulation Study of an Extended Density DC Glow Toroidal Plasma Source

International Nuclear Information System (INIS)

Granda-Gutierrez, E. E.; Piedad-Beneitez, A. de la; Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Benitez-Read, J. S.; Pacheco-Sotelo, J. O.; Pena-Eguiluz, R.; Mercado-Cabrera, A.; Valencia A, R.; Barocio, S. R.

2006-01-01

Conventional wisdom assigns the DC glow discharge regime to plasma currents below ∼500 mA values, beyond which the discharge falls into the anomalous glow and the turbulent arc regimes. However, we have found evidence that, during toroidal discharges, this barrier can be ostensibly extended up to 800 mA. Thus, a computer simulation has been applied to the evolution of the main electrical characteristics of such a glow discharge plasma in a toroidal vessel in order to design and construct a respective voltage/current controlled source. This should be able to generate a DC plasma in the glow regime with which currents in the range 10-3-100 A can be experimented and 109-1010 cm-3 plasma densities can be achieved to PIII optimization purposes. The plasma is modelled as a voltage-controlled current source able to be turned on whenever the breakdown voltage is reached across the gap between the anode and the vessel wall. The simulation outcome fits well our experimental measurements showing that the plasma current obeys power laws that are dependent on the power current and other control variables such as the gas pressure

PREVAIL: IBM's e-beam technology for next generation lithography

Science.gov (United States)

Pfeiffer, Hans C.

2000-07-01

PREVAIL - Projection Reduction Exposure with Variable Axis Immersion Lenses represents the high throughput e-beam projection approach to NGL which IBM is pursuing in cooperation with Nikon Corporation as alliance partner. This paper discusses the challenges and accomplishments of the PREVAIL project. The supreme challenge facing all e-beam lithography approaches has been and still is throughput. Since the throughput of e-beam projection systems is severely limited by the available optical field size, the key to success is the ability to overcome this limitation. The PREVAIL technique overcomes field-limiting off-axis aberrations through the use of variable axis lenses, which electronically shift the optical axis simultaneously with the deflected beam so that the beam effectively remains on axis. The resist images obtained with the Proof-of-Concept (POC) system demonstrate that PREVAIL effectively eliminates off- axis aberrations affecting both resolution and placement accuracy of pixels. As part of the POC system a high emittance gun has been developed to provide uniform illumination of the patterned subfield and to fill the large numerical aperture projection optics designed to significantly reduce beam blur caused by Coulomb interaction.

Electron beam extraction from a HVPES

Energy Technology Data Exchange (ETDEWEB)

Marghitu, S; Cramariuc, R [Accelerators Laboratory, Institute of Physics and Technology for Radiation Devices, PO Box MG-06, R-76900 Bucharest (Romania); Nicolescu, I; Niculescu, M [Institute of Research and Design for Electrical Engineering, ICPE - Electrostatica, Splaiul Unirii 313, Sect. 3, R-74204 Bucharest (Romania)

1997-12-31

The results of the research concerning the extraction system of the fast electrons from a cold cathode high voltage glow discharge plasma electron source (HVPES) are presented. For using the electron beam in a more flexible way, that is changing the shape of the minimum cross-section, (or beam cross-over), of the beam in a sample S frontal plane, without perturbing the discharge parameters, some modifications to a reference internal geometry were tested. Finally, a geometry was found in which the discharge volume may be separated in two parts, one, `a discharge space`, filled with plasma and fast electrons and another, `working space`, occupied specially by the fast electron beam. In this new geometry the electrical discharge parameters, I{sub d} - discharge current, U{sub d} - discharge voltage, were the same as for the reference geometry. (authors) 5 refs., 4 figs., 3 tabs.

E-beam heated linear solenoid reactors

International Nuclear Information System (INIS)

Benford, J.; Bailey, V.; Oliver, D.

1976-01-01

A conceptual design and system analysis shows that electron beam heated linear solenoidal reactors are attractive for near term applications which can use low gain fusion sources. Complete plant designs have been generated for fusion based breeders of fissile fuel over a wide range of component parameters (e.g., magnetic fields, reactor lengths, plasma densities) and design options (e.g., various radial and axial loss mechanisms). It appears possible that a reactor of 100 to 300 meters length operating at power levels of 1000 MWt can economically produce 2000 to 8000 kg/yr of 233 U to supply light water reactor fuel needs beyond 2000 A.D. Pure fusion reactors of 300 to 500 meter lengths are possible. Physics and operational features of reactors are described. Beam heating by classical and anomalous energy deposition is reviewed. The technology of the required beams has been developed to MJ/pulse levels, within a factor of 20 of that needed for full scale production reactors. The required repetitive pulsing appears practical

Leptoquark production with polarized γe beams

International Nuclear Information System (INIS)

Aliev, T.M.; Mustafaev, Kh.A.

1991-01-01

Possibilities of single production of the scalar leptoquark and also of its supersymmetric partner in polarized γe beams are studied in E 6 superstring theories. Expressions for the differential and total cross sections are obtained and analyzed. It is shown that the scalar leptoquark of mass 300 GeV can be detected even for a very small interaction constant γ 2 /4π∼10 -2 a and its supersymmetric partner can be detected for γ 2 /4π∼10 -2 a. The spin asymmetry due to the photon-beam polarization and the effect of this polarization on both the differential and the total cross sections are studied in detail. It is shown that study of the spin asymmetry and the effect of the photon-beam polarization can be used to extract information about the leptoquark masses

Oxidation of 1020 steel in the abnormal glow discharge

International Nuclear Information System (INIS)

Zúñiga, J A García; Santos, A Sarmiento; Gómez, E Y Soto

2017-01-01

1020 steel is a material very used for surface treatment in the abnormal glow discharge. Because the composition of the gaseous atmosphere has an important influence on the results of plasma treatment, in this work the oxidation process of 1020 steel is verified on the abnormal glow discharge under different concentrations of air (20% to 100%) at temperatures of 600°C and 900°C. For each atmosphere used mass variation is measured during the process of surface oxidation, the structure and microstructure of the oxide film formed is observed and also its mechanical properties through its microhardness. (paper)

Spectroscopy and probe diagnostics of dc spherical glow discharge

International Nuclear Information System (INIS)

Zhovtyansky, V.A.; Nazarenko, V.G.; Syrotyuk, R.P.

2016-01-01

Probe and spectroscopic investigations of a spherical glow discharge (GD) were done in nitrogen and argon plasma. There were obtained the distributions of electron temperature and electron density in a discharge gap as well as plasma potential distribution. These results were compared with theoretical ones and the conclusion about their convergence was done in the present study. Particular attention was paid to the anode processes role in the formation of self-organized structure in a spherical glow discharge. It was shown the necessity of taking into account the possibility of the anode potential drop forming in this discharge region

Simulation of the Beam-Beam Effects in e+e- Storage Rings with a Method of Reducing the Region of Mesh

Energy Technology Data Exchange (ETDEWEB)

Cai, Yunhai

2000-08-31

A highly accurate self-consistent particle code to simulate the beam-beam collision in e{sup +}e{sup -} storage rings has been developed. It adopts a method of solving the Poisson equation with an open boundary. The method consists of two steps: assigning the potential on a finite boundary using the Green's function, and then solving the potential inside the boundary with a fast Poisson solver. Since the solution of the Poisson's equation is unique, the authors solution is exactly the same as the one obtained by simply using the Green's function. The method allows us to select much smaller region of mesh and therefore increase the resolution of the solver. The better resolution makes more accurate the calculation of the dynamics in the core of the beams. The luminosity simulated with this method agrees quantitatively with the measurement for the PEP-II B-factory ring in the linear and nonlinear beam current regimes, demonstrating its predictive capability in detail.

A simple method of dosimetry for E-beam radiation

International Nuclear Information System (INIS)

Spencer, D.S.; Thalacker, V.P.; Chasman, J.N.; Siegel, S.

1985-01-01

A simple method utilizing a photochromic 'intensity label' for monitoring electron-beam sources was evaluated. The labels exhibit a color change upon exposure to UV or e-beam radiation. A correlation was found between absorbed energy and Gardner Color Index at low electron-beam doses. (author)

Space structure of the glow discharge with free side boundary

International Nuclear Information System (INIS)

Yatsenko, N.A.

1995-01-01

The main purpose of this work is to reveal physical reasons, which are responsible for the formation of space structure of glow type discharge with free side boundary, both in DC and in RF electric fields. By now extensive experimental material have been accumulated in discharge physics. Also many theoretical models have been proposed for describing separate parts of discharge with the cold electrodes (cathode and anode regions, positive column and transition zones - glow luminescence and Farraday's dark space of DC-discharge, electrode regions and plasma column of RF capacitive discharge). As this takes place, the majority of known works are devoted to some one part of gas discharge - positive column, electrode regions, transition zones and so on. At the same time just now we don't know anything about space structure of free, steady-state gas discharge of glow type, as a whole, especially when the pressure p much-gt 1 Torr

Conceptual design of a large E-beam-pumped KrF laser for ICF commercial applications

International Nuclear Information System (INIS)

Harris, D.B.; Waganer, L.M.; Zuckerman, D.S.; Bowers, D.A.

1986-01-01

Two types of KrF lasers appear attractive as a driver for an ICF electric power plant. The original concept uses large electron-beam-pumped amplifiers and pure angular multiplexing to deliver short, shaped pulses to the target. A recently conceived alternate concept uses many small, long-pulse e-beam sustained discharge lasers which transfer their energy through the forward Raman process to a multiplexed set of beams to deliver the energy to target. Preliminary comparisons of the two systems indicate that the original concept has both a lower cost and a lower system efficiency, and both concepts appear to be nearly equally attractive as an ICF driver for an electric power plant. This paper examines a 4.8 MJ, 5 Hz KrF laser system designed using the original concept. The laser uses 24 main amplifiers arranged in eight sets of three amplifiers each. This layout optimizes both the optical system and the gas flow system, and uses a simple target illumination scheme that provides neutron shielding to allow hands-on maintenance in the laser hall

Iridium Coating Deposited by Double Glow Plasma Technique — Effect of Glow Plasma on Structure of Coating at Single Substrate Edge

International Nuclear Information System (INIS)

Wu Wangping; Chen Zhaofeng; Liu Yong

2012-01-01

Double glow plasma technique has a high deposition rate for preparing iridium coating. However, the glow plasma can influence the structure of the coating at the single substrate edge. In this study, the iridium coating was prepared by double glow plasma on the surface of single niobium substrate. The microstructure of iridium coating at the substrate edge was observed by scanning electron microscopy. The composition of the coating was confirmed by energy dispersive spectroscopy and X-ray diffraction. There was a boundary between the coating and the substrate edge. The covered area for the iridium coating at the substrate edge became fewer and fewer from the inner area to the outer flange-area. The bamboo sprout-like particles on the surface of the substrate edge were composed of elemental niobium. The substrate edge was composed of the Nb coating and there was a transition zone between the Ir coating and the Nb coating. The interesting phenomenon of the substrate edge could be attributed to the effects of the bias voltages and the plasma cloud in the deposition chamber. The substrate edge effect could be mitigated or eliminated by adding lots of small niobium plates around the substrate in a deposition process. (plasma technology)

Polarized proton beam for eRHIC

Energy Technology Data Exchange (ETDEWEB)

Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-05-03

RHIC has provided polarized proton collisions from 31 GeV to 255 GeV in the past decade. To preserve polarization through numerous depolarizing resonances through the whole accelerator chain, harmonic orbit correction, partial snakes, horizontal tune jump system and full snakes have been used. In addition, close attentions have been paid to betatron tune control, orbit control and beam line alignment. The polarization of 60% at 255 GeV has been delivered to experiments with 1.8×10¹¹ bunch intensity. For the eRHIC era, the beam brightness has to be maintained to reach the desired luminosity. Since we only have one hadron ring in the eRHIC era, existing spin rotator and snakes can be converted to six snake configuration for one hadron ring. With properly arranged six snakes, the polarization can be maintained at 70% at 250 GeV. This paper summarizes the effort and plan to reach high polarization with small emittance for eRHIC.

Bidimensional characterization of the emission spectra in a direct current atmospheric pressure glow discharge

International Nuclear Information System (INIS)

Orejas, Jaime; Pisonero, Jorge; Bordel, Nerea; Nelis, Thomas; Guillot, Philippe; Sanz-Medel, Alfredo

2012-01-01

An in-house atmospheric pressure glow discharge source, designed to be used as ionization/desorption source for ambient mass spectrometry, has been electrically characterized, and its optical emission spectra evaluated in detail. Electrical characterization showed that the plasma regime can vary from glow discharge to arc discharge depending on operating conditions (i.e. He flow rate and inter electrode distance). Furthermore, bidimensional images of the optical emission of some plasma species using filters as wavelength selectors, were registered from inside and outside the discharge chamber (inner region and afterglow region respectively), showing the spatial distribution of excited species (i.e. He*, N 2 + and O*). These distribution patterns are useful to study the chemistry of the discharge plasma, since different production pathways and different excitation energies affect the presence of these species in the plasma regions. - Highlights: ► An in-house APGD is characterized through electrical and OES measurements. ► Interelectrode distance had more effect on electric regime than He flow rate. ► Internal plume images showed differences on the production pathways for each species. ► Higher interelectrode distances and He flow rates showed better afterglow conditions.

Thermoluminescence properties of Al{sub 2}O{sub 3}:Tb nanoparticles irradiated by gamma rays and 85 MeV C{sup 6+} ion beam

Energy Technology Data Exchange (ETDEWEB)

Salah, Numan, E-mail: nsalah@kau.edu.sa [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Alharbi, Najlaa D. [Sciences Faculty for Girls, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Habib, Sami S. [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Lochab, S.P. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

2015-11-15

Carbon ions beam is recently recognized as an ideal cancer treatment modality, because of its excellent local tumor control. These ions have a high relative biological effectiveness resulting from high linear energy transfer (LET) and their sharp Bragg peak. However, the dose of those energetic ions needs to be measured with great precision using a proper dosimeter. Aluminum Oxide (Al{sub 2}O{sub 3}) is a highly luminescent phosphor widely used for radiation dosimetry using thermoluminesence (TL) technique. In this work nanoparticles of this material activated by different elements like Eu, Tb, Dy, Cu and Ag were evaluated for their TL response to gamma rays irradiation. Tb doped sample is found to be the most sensitive sample, which could be selected for exposure to 85 MeV C{sup 6+} ion beam in the fluence range 10{sup 9}–10{sup 13} ions/cm{sup 2}. The obtained result shows that C ion beam irradiated sample has a simple glow curve structure with a prominent glow peak at around 230 °C. This glow curve has a dosimetric peak better than those induced by gamma rays. This glow peak exhibits a linear response in the range 10{sup 9}–10{sup 11} ions/cm{sup 2}, corresponding to the equivalent absorbed doses 0.285–28.5 kGy. The absorbed doses, penetration depths and main energy loss were calculated using TRIM code based on the Monte Carlo simulation. The wide linear response of Al{sub 2}O{sub 3}:Tb nanoparticles along with the low fading makes this low cost nanomaterial a good candidate for C ion beam dosimetry. - Highlights: • Nanoparticles of Al{sub 2}O{sub 3} doped with Eu, Tb, Dy, Cu and Ag were synthesised. • They were evaluated for their TL response to gamma rays and C ion beam irradiation. • Tb doped sample is the most sensitive sample to gamma rays. • Al{sub 2}O{sub 3}:Tb was exposed to 85 MeV C{sup 6+} ion beam in the fluence range 10{sup 9}-10{sup 13} ions/cm{sup 2}. • The glow peak induced by C ions has a linear response in the range 10{sup 9

An algorithm for unified analysis on the thermoluminescence glow curve

International Nuclear Information System (INIS)

Chung, K.S.; Park, C.Y.; Lee, J.I.; Kim, J.L.

2014-01-01

An algorithm was developed to integrally handle excitation by radiation, relaxation and luminescence by thermal or optical stimulation in thermoluminescence (TL) and optically stimulated luminescence (OSL) processes. This algorithm reflects the mutual interaction between traps through a conduction band. Electrons and holes are created by radiation in the beginning, and these electrons move to the trap through the conduction band. These holes move to the recombination center through a valence band. The ratio of the electrons allocated to each trap differs with the recombination probability and these values also relevant to the process of luminescence. Accordingly, the glow curve can be interpreted by taking the rate of electron–hole pairs created by ionizing radiation as a unique initial condition. This method differs from the conventional method of interpreting the measured glow curve with the initial electron concentration allocated to each trap at the end of irradiation. A program using the Visual Studio's C# subsystem was made to realize such a developed algorithm. To verify this algorithm it was applied to LiF:Mg,Cu,Si. The TL glow curve was deconvoluted with a model of five traps, one deep trap and one recombination center (RC). - Highlights: • TL glow curve deconvolution employing interacting model. • Simulation both irradiation and TL readout stages for various dose level. • Application in the identification TL kinetics of LiF:Mg,Cu,Si TLD

Monte Carlo simulation of fast electrons and heavy particles in the CDS of nitrogen dc glow discharge

International Nuclear Information System (INIS)

Yu, W.; Zhang, L.Z.; Wang, J.L.; Han, L.; Fu, G.S.

2001-01-01

The characteristics of fast electrons (e - ) and heavy particles (N 2 + , N + , N 2f , N f ) in the cathode dark space (CDS) of nitrogen dc glow discharge are simultaneously studied by Monte Carlo simulation. The calculated energy and angular distributions of these particles at different positions from the cathode provide a clear picture of their transport behaviours within the CDS. The density and mean energy of these particles indicate that the electrons and the atomic ions (N + ) are the main high-energy species and the molecular ions (N 2 + ) are the major ions in the CDS. It can be seen from the energy distributions of the bombarding particles at the cathode surface that the molecular ions and the fast atoms (N f ) are the main active species participating in the cathode nitride material synthesis process. The influence of the backscattering of the electrons from the negative glow to the CDS is also investigated. All the calculated results provide good information on the spatial characteristics of the particles considered in this paper and also their internal connections in the CDS of nitrogen dc glow discharge. (author)

E-beam-pumped semiconductor lasers

Science.gov (United States)

Rice, Robert R.; Shanley, James F.; Ruggieri, Neil F.

1995-04-01

The collapse of the Soviet Union opened many areas of laser technology to the West. E-beam- pumped semiconductor lasers (EBSL) were pursued for 25 years in several Soviet Institutes. Thin single crystal screens of II-VI alloys (ZnxCd1-xSe, CdSxSe1-x) were incorporated in laser CRTs to produce scanned visible laser beams at average powers greater than 10 W. Resolutions of 2500 lines were demonstrated. MDA-W is conducting a program for ARPA/ESTO to assess EBSL technology for high brightness, high resolution RGB laser projection application. Transfer of II-VI crystal growth and screen processing technology is underway, and initial results will be reported. Various techniques (cathodoluminescence, one- and two-photon laser pumping, etc.) have been used to assess material quality and screen processing damage. High voltage (75 kV) video electronics were procured in the U.S. to operate test EBSL tubes. Laser performance was documented as a function of screen temperature, beam voltage and current. The beam divergence, spectrum, efficiency and other characteristics of the laser output are being measured. An evaluation of the effect of laser operating conditions upon the degradation rate is being carried out by a design-of-experiments method. An initial assessment of the projected image quality will be performed.

Thermoluminescence glow curve analysis and CGCD method for erbium doped CaZrO{sub 3} phosphor

Energy Technology Data Exchange (ETDEWEB)

Tiwari, Ratnesh, E-mail: 31rati@gmail.com [Department of Physics, Bhilai Institute of Technology, Raipur, 493661 (India); Chopra, Seema [Department Physics, G.D Goenka Public School (India)

2016-05-06

The manuscript report the synthesis, thermoluminescence study at fixed concentration of Er{sup 3+} (1 mol%) doped CaZrO{sub 3} phosphor. The phosphors were prepared by modified solid state reaction method. The powder sample was characterized by thermoluminescence (TL) glow curve analysis. In TL glow curve the optimized concentration in 1mol% for UV irradiated sample. The kinetic parameters were calculated by computerized glow curve deconvolution (CGCD) techniaue. Trapping parameters gives the information of dosimetry loss in prepared phosphor and its usability in environmental monitoring and for personal monitoring. CGCD is the advance tool for analysis of complicated TL glow curves.

Particle control in DIII-D with helium glow discharge conditioning

International Nuclear Information System (INIS)

Jackson, G.L.; Taylor, T.S.; Taylor, P.L.

1990-01-01

Helium glow discharge conditioning of DIII-D is routinely used before every tokamak discharge to desorb hydrogen from the graphite tiles, which are the plasma facing surfaces for the floor, inner wall and top of the vessel. In addition to reducing hydrogen fuelling of the plasma by the graphite surfaces, helium glow discharges are also effective in removing low-Z impurities, primarily in the form of carbon monoxide and hydrocarbons, and this has permitted higher current divertor operation and more rapid recovery from tokamak disruptions. Since the implementation of repetitive helium glow wall conditioning, the parameter space in which tokamak discharges in DIII-D can be obtained has been expanded to include the first observations of limiter H-mode confinement, the Ohmic H-mode with periods of up to 150 ms that are free of edge localized modes, more reliable low q operation with volume averaged beta of up to 9.3%, improved control over locked modes and plasma discharges at lower electron density. (author). 37 refs, 12 figs, 1 tab

Intense e-beam interaction with matter

International Nuclear Information System (INIS)

Ritchie, R.H.; Crawford, O.H.

1984-01-01

This document describes work done in this period on certain nonlinear processes of potential importance at high energy densities in condensed matter, and on the theory of the electron slowing-down-cascade spectrum engendered in solids by e-beams

Photo-preionization stabilized high-pressure glow-discharge lasers

International Nuclear Information System (INIS)

Von Bergmann, H.M.

1980-07-01

Simple nanosecond stabilization and pulsing techniques were developed to excite high-pressure gas-discharge lasers at high overvoltages and high specific power loadings. The techniques were applied to a variety of ultraviolet and visible laser systems employing fast transmission line pulsers and conventional LC generators. The stabilization procedures are evaluated and the parameters which control the geometry and uniformity of the high-pressure glow discharges are investigated. A detailed study of the formation, distribution and spectral characteristics of the fast surface corona discharges is provided. The stabilization and pulsing techniques were used for the corona and glow discharge excitation of high-pressure ultraviolet N 2 lasers. A detailed spectrally- and temporally-resolved study of the gain, fluorescence and energy extraction characteristics of the atmospheric pressure N 2 plasmas is provided

The experience with JET's combined dc/Rf glow discharge cleaning (GDC) system

International Nuclear Information System (INIS)

Pearce, R.J.H.; Andrew, P.; Bryan, S.

1996-01-01

The JET Tokamak was fitted with four new electrodes of novel design, each powered from individual computer controlled dc and RF supplies. Details of enhancements and problems from 15 months experience with the system are outlined. Experiments were performed to assess the effect of RF on the glow discharge characteristics, and to establish stable glow at low pressure and high voltage. JET combined RF/dc glow discharge cleaning (GDC) had no significant advantages over pure dc GDC, provided highly stable dc current control was obtained. In fact, the mechanically weak electrode inductor spiral required to allow RF posed a distinct disadvantage. The electrodes were converted to simple plates, following damage caused by halo currents during Tokamak plasma disruptions. The performance of these electrodes was assessed. Future developments in the JET GDC system are outlined. (Author)

Positional glow curve simulation for thermoluminescent detector (TLD) system design

International Nuclear Information System (INIS)

Branch, C.J.; Kearfott, K.J.

1999-01-01

Multi- and thin element dosimeters, variable heating rate schemes, and glow-curve analysis have been employed to improve environmental and personnel dosimetry using thermoluminescent detectors (TLDs). Detailed analysis of the effects of errors and optimization of techniques would be highly desirable. However, an understanding of the relationship between TL light production, light attenuation, and precise heating schemes is made difficult because of experimental challenges involved in measuring positional TL light production and temperature variations as a function of time. This work reports the development of a general-purpose computer code, thermoluminescent detector simulator, TLD-SIM, to simulate the heating of any TLD type using a variety of conventional and experimental heating methods including pulsed focused or unfocused lasers with Gaussian or uniform cross sections, planchet, hot gas, hot finger, optical, infrared, or electrical heating. TLD-SIM has been used to study the impact on the TL light production of varying the input parameters which include: detector composition, heat capacity, heat conductivity, physical size, and density; trapped electron density, the frequency factor of oscillation of electrons in the traps, and trap-conduction band potential energy difference; heating scheme source terms and heat transfer boundary conditions; and TL light scatter and attenuation coefficients. Temperature profiles and glow curves as a function of position time, as well as the corresponding temporally and/or spatially integrated glow values, may be plotted while varying any of the input parameters. Examples illustrating TLD system functions, including glow curve variability, will be presented. The flexible capabilities of TLD-SIM promises to enable improved TLD system design

The Effects of Lamp Spectral Distribution on Sky Glow over Observatories

Science.gov (United States)

2015-01-01

overhead sky glow as a function of distance up to 300 km, from a variety of lamp types, including common gas discharge lamps and several types of LED...distance up to 300 km, from a variety of lamp types, in- cluding common gas discharge lamps and several types of LED lamps . We conclude for both...MAR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE The Effects of Lamp Spectral Distribution on Sky Glow

Future e+e- linear colliders and beam-beam effects

International Nuclear Information System (INIS)

Wilson, P.B.

1986-05-01

Numerous concepts, ranging from conventional to highly exotic, hae been proposed for the acceleration of electrons and positrons to very high energies. For any such concept to be viable, it must be possible to produce from it a set of consistent parameters for one of these ''benchmark'' machines. Attention is directed to the choice of parameters for a collider in the 300 GeV energy range, operating at a gradient on the order of 200 MV/m, using X-band power sources to drive a conventional disk-loaded accelerating structure. These rf power sources, while not completely conventional represent a reasonable extrapolation from present technology. The choice of linac parameters is strongly coupled to various beam-beam effects which take place when the electron and positron bunches collide. We summarize these beam-beam effects, and then return to the rf design of a 650 GeV center-of-mass collider. 14 refs

Mechanical and tribological properties of AISI 304 stainless steel nitrided by glow discharge compared to ion implantation and plasma immersion ion implantation

International Nuclear Information System (INIS)

Foerster, C.E.; Serbena, F.C.; Silva, S.L.R. da; Lepienski, C.M.; Siqueira, C.J. de M.; Ueda, M.

2007-01-01

Results about mechanical and tribological behavior of AISI 304 stainless steel nitrided by three different ion beam processes - glow discharge (GD), ion implantation (II) and plasma immersion ion implantation (PI3) are reported. Expanded austenite γ N and nitrides phases (Fe 2+x N, γ'-Fe 4 N and Cr-N) were identified as a function of nitriding conditions. Hardness (H) and elastic modulus (E) profiles were obtained by instrumented penetration. The hardness reached values as high as 21 GPa by PI3. Tribological behavior was studied by reciprocating sliding tests with a WC (Co) ball at room temperature (RT) in dry condition. Different wear regimes were identified in the friction coefficient profiles. The profile form and the running-in distance are strongly dependent on the nitriding process. Adhesive and abrasive wear components can be inferred from these friction profiles. Hardness and tribological performance, after the nitriding processes, are discussed in terms of surface microstructure

On plasma ion beam formation in the Advanced Plasma Source

International Nuclear Information System (INIS)

Harhausen, J; Foest, R; Hannemann, M; Ohl, A; Brinkmann, R P; Schröder, B

2012-01-01

The Advanced Plasma Source (APS) is employed for plasma ion-assisted deposition (PIAD) of optical coatings. The APS is a hot cathode dc glow discharge which emits a plasma ion beam to the deposition chamber at high vacuum (p ≲ 2 × 10 −4 mbar). It is established as an industrial tool but to date no detailed information is available on plasma parameters in the process chamber. As a consequence, the details of the generation of the plasma ion beam and the reasons for variations of the properties of the deposited films are barely understood. In this paper the results obtained from Langmuir probe and retarding field energy analyzer diagnostics operated in the plasma plume of the APS are presented, where the source was operated with argon. With increasing distance to the source exit the electron density (n e ) is found to drop by two orders of magnitude and the effective electron temperature (T e,eff ) drops by a factor of five. The parameters close to the source region read n e ≳ 10 11 cm −3 and T e,eff ≳ 10 eV. The electron distribution function exhibits a concave shape and can be described in the framework of the non-local approximation. It is revealed that an energetic ion population leaves the source region and a cold ion population in the plume is build up by charge exchange collisions with the background neutral gas. Based on the experimental data a scaling law for ion beam power is deduced, which links the control parameters of the source to the plasma parameters in the process chamber. (paper)

Removal of the codeposited carbon layer using He-O glow discharge

International Nuclear Information System (INIS)

Kunz, C.L.; Causey, R.A.; Clift, M.; Wampler, W.R.; Cowgill, D.F.

2007-01-01

In this study we examine the combination of a He-O glow discharge with heating as a possible technique to remove deuterium from TFTR tiles. Samples were cut from a relatively large area containing a uniform codeposited layer of deuterium and carbon. Auger/SEM was used to generate micrographs of each of the samples. The samples were also examined using Rutherford backscattering to determine the near surface composition. Individual samples were then exposed to a He-O glow discharge while being heated. After the exposure, the samples were returned for Auger/SEM and RBS of the same areas examined prior to the exposure. Comparing the samples before and after exposure revealed that the amount of the codeposited layer removed was significantly less than 1 μm. Removal rates this low would suggest that He-O glow discharge with heating is insufficient to remove the thick layers predicted for ITER in a timely fashion

Differences in TLD 600 and TLD 700 glow curves derived from distict mixed gamma/neutron field irradiations

International Nuclear Information System (INIS)

Cavalieri, Tassio A.; Castro, Vinicius A.; Siqueira, Paulo T.D.

2013-01-01

In Neutron Capture Therapy, a thermal neutron beam shall impinge on a specific nuclide, such as 10 B, to promote a nuclear reaction which releases the useful therapeutic energy. A nuclear reactor is usually used as the neutron source, and therefore field contaminants such as gamma and high energy neutrons are also present in the field. However, mixed field dosimetry still stands as a challenge in some cases, due to the difficulty to experimentally discriminate the dose from each field component. For the mixed field dosimetry, the International Commission on Radiation end Units (ICRU) recommends the use of detector pairs with different responses for each beam component. The TLD 600/700 pair meets this need, because these LiF detectors have different Li isotopes concentration, with distinct thermal neutron responses because 6 Li presents a much higher neutron capture cross section than does 7 Li for low energy neutrons. TLD 600 is 6 Li enriched while TLD 700 is 7 Li enriched. However, depending on the neutron spectrum presented in the mixed field, TLD 700 response to thermal neutrons cannot be disregarded. This work aims to study the difference in TLD 600 and TLD 700 glow curves when these TLDs are submitted to mixed fields of different energy spectra and components balance. The TLDs were irradiated in a pure gamma source, and in mixed fields from an AmBe sealed source and from the IPEN/MB-01 reactor. These TLDs were read and had their two main dosimetric regions analyzed to observe the differences in the glow curves of these TLDs in each irradiation. Field components discrimination was achieved through Monte Carlo simulations run with MCNP radiation transport code. (author)

Using the computerized glow curve deconvolution method and the R package tgcd to determination of thermoluminescence kinetic parameters of chilli powder samples by GOK model and OTOR one

Energy Technology Data Exchange (ETDEWEB)

Sang, Nguyen Duy, E-mail: ndsang@ctu.edu.vn [College of Rural Development, Can Tho University, Can Tho 270000 (Viet Nam); Faculty of Physics and Engineering Physics, University of Science, Ho Chi Minh 700000 (Viet Nam); Van Hung, Nguyen [Nuclear Research Institute, VAEI, Dalat 670000 (Viet Nam); Van Hung, Tran; Hien, Nguyen Quoc [Research and Development Center for Radiation Technology, VAEI, Ho Chi Minh 700000 (Viet Nam)

2017-03-01

Highlights: • TL analysis aims to calculate the kinetic parameters of the chilli powder. • There is difference of the kinetic parameters caused by the difference of radiation doses. • There is difference of the kinetic parameters due to applying GOK model or OTOR one. • The software R is apllied for the first time in TL glow curve analysis of the chilli powder. - Abstract: The kinetic parameters of thermoluminescence (TL) glow peaks of chilli powder irradiated by gamma rays with the different doses of 0, 4 and 8 kGy have been calculated and estimate by computerized glow curve deconvolution (CGCD) method and the R package tgcd by using the TL glow curve data. The kinetic parameters of TL glow peaks (i.e. activation energies (E), order of kinetics (b), trapping and recombination probability coefficients (R) and frequency factors (s)) are fitted by modeled general-orders of kinetics (GOK) and one trap-one recombination (OTOR). The kinetic parameters of the chilli powder are different toward the difference of the sample time-storage, radiation doses, GOK model and OTOR one. The samples spending the shorter period of storage time have the smaller the kinetic parameters values than the samples spending the longer period of storage. The results obtained as comparing the kinetic parameters values of the three samples show that the value of non-irradiated samples are lowest whereas the 4 kGy irradiated-samples’ value are greater than the 8 kGy irradiated-samples’ one time.

Quantitative approach for optimizing e-beam condition of photoresist inspection and measurement

Science.gov (United States)

Lin, Chia-Jen; Teng, Chia-Hao; Cheng, Po-Chung; Sato, Yoshishige; Huang, Shang-Chieh; Chen, Chu-En; Maruyama, Kotaro; Yamazaki, Yuichiro

2018-03-01

Severe process margin in advanced technology node of semiconductor device is controlled by e-beam metrology system and e-beam inspection system with scanning electron microscopy (SEM) image. By using SEM, larger area image with higher image quality is required to collect massive amount of data for metrology and to detect defect in a large area for inspection. Although photoresist is the one of the critical process in semiconductor device manufacturing, observing photoresist pattern by SEM image is crucial and troublesome especially in the case of large image. The charging effect by e-beam irradiation on photoresist pattern causes deterioration of image quality, and it affect CD variation on metrology system and causes difficulties to continue defect inspection in a long time for a large area. In this study, we established a quantitative approach for optimizing e-beam condition with "Die to Database" algorithm of NGR3500 on photoresist pattern to minimize charging effect. And we enhanced the performance of measurement and inspection on photoresist pattern by using optimized e-beam condition. NGR3500 is the geometry verification system based on "Die to Database" algorithm which compares SEM image with design data [1]. By comparing SEM image and design data, key performance indicator (KPI) of SEM image such as "Sharpness", "S/N", "Gray level variation in FOV", "Image shift" can be retrieved. These KPIs were analyzed with different e-beam conditions which consist of "Landing Energy", "Probe Current", "Scanning Speed" and "Scanning Method", and the best e-beam condition could be achieved with maximum image quality, maximum scanning speed and minimum image shift. On this quantitative approach of optimizing e-beam condition, we could observe dependency of SEM condition on photoresist charging. By using optimized e-beam condition, measurement could be continued on photoresist pattern over 24 hours stably. KPIs of SEM image proved image quality during measurement and

A computerized glow curve analysis (GCA) method for WinREMS thermoluminescent dosimeter data using MATLAB

International Nuclear Information System (INIS)

Harvey, John A.; Rodrigues, Miesher L.; Kearfott, Kimberlee J.

2011-01-01

A computerized glow curve analysis (GCA) program for handling of thermoluminescence data originating from WinREMS is presented. The MATLAB program fits the glow peaks using the first-order kinetics model. Tested materials are LiF:Mg,Ti, CaF 2 :Dy, CaF 2 :Tm, CaF 2 :Mn, LiF:Mg,Cu,P, and CaSO 4 :Dy, with most having an average figure of merit (FOM) of 1.3% or less, with CaSO 4 :Dy 2.2% or less. Output is a list of fit parameters, peak areas, and graphs for each fit, evaluating each glow curve in 1.5 s or less. - Highlights: → Robust algorithm for performing thermoluminescent dosimeter glow curve analysis. → Written in MATLAB so readily implemented on variety of computers. → Usage of figure of merit demonstrated for six different materials.

Bidimensional characterization of the emission spectra in a direct current atmospheric pressure glow discharge

Energy Technology Data Exchange (ETDEWEB)

Orejas, Jaime [University of Oviedo, Department of Physics, C/ Gonzazlez Quiros S/N, Mieres (Spain); Pisonero, Jorge, E-mail: pisonerojorge@uniovi.es [University of Oviedo, Department of Physics, C/ Gonzazlez Quiros S/N, Mieres (Spain); Bordel, Nerea [University of Oviedo, Department of Physics, C/ Gonzazlez Quiros S/N, Mieres (Spain); Nelis, Thomas [Bern University of Applied Sciences, Quellgasse 21, 2501 Bienne (Switzerland); Guillot, Philippe [DPHE, CUFR J. F. Champollion, Universite de Toulouse, Place de Verdun, Albi (France); Sanz-Medel, Alfredo, E-mail: asm@uniovi.es [University of Oviedo, Department of Physical and Analytical Chemistry, C/ Julian Claveria 8, Oviedo (Spain)

2012-10-15

An in-house atmospheric pressure glow discharge source, designed to be used as ionization/desorption source for ambient mass spectrometry, has been electrically characterized, and its optical emission spectra evaluated in detail. Electrical characterization showed that the plasma regime can vary from glow discharge to arc discharge depending on operating conditions (i.e. He flow rate and inter electrode distance). Furthermore, bidimensional images of the optical emission of some plasma species using filters as wavelength selectors, were registered from inside and outside the discharge chamber (inner region and afterglow region respectively), showing the spatial distribution of excited species (i.e. He*, N{sub 2}{sup +} and O*). These distribution patterns are useful to study the chemistry of the discharge plasma, since different production pathways and different excitation energies affect the presence of these species in the plasma regions. - Highlights: Black-Right-Pointing-Pointer An in-house APGD is characterized through electrical and OES measurements. Black-Right-Pointing-Pointer Interelectrode distance had more effect on electric regime than He flow rate. Black-Right-Pointing-Pointer Internal plume images showed differences on the production pathways for each species. Black-Right-Pointing-Pointer Higher interelectrode distances and He flow rates showed better afterglow conditions.

Composition dependence of glow peak temperature in KCl1-xBrx doped with divalent cations

International Nuclear Information System (INIS)

Perez-Salas, R; Aceves, R; RodrIguez-Mijangos, R; Riveros, H G; Duarte, C

2004-01-01

Thermoluminescence measurements of β-irradiated Eu 2+ - and Ca 2+ - doped KCl 1-x KBr x solid solutions excited at room temperature have been carried out to identify the effect of composition on the glow peaks. A typical glow peak has been distinguished for each composition. A linear dependence of its temperature on the composition x has been found. These results indicate that for divalent impurity-doped alkali halide solid solutions these glow peak temperatures are mostly dependent on the lattice constant of the host than on the size of the anion or impurity cation

Numerical analysis of thermoluminescence glow curves; Analisis numerico de las cruvas de termoluminiscencia

Energy Technology Data Exchange (ETDEWEB)

Gomez Ros, J M; Delgado, A

1989-07-01

This report presents a method for the numerical analysis of complex thermoluminescence glow curves resolving the individual glow peak components. The method employs first order kinetics analytical expressions and is based In a Marquart-Levenberg minimization procedure. A simplified version of this method for thermoluminescence dosimetry (TLD) is also described and specifically developed to operate whit Lithium Fluoride TLD-100. (Author). 36 refs.

E-Government Maturity Model for Sustainable E-Government Services from the Perspective of Developing Countries

Directory of Open Access Journals (Sweden)

Pusp Raj Joshi

2018-06-01

Full Text Available Electric government (e-government projects in developing countries are facing many challenges to deliver sustainable e-government services. From the existing literature, we found that most of the studies considered lack of technology, and limitations in budgets and human resources as the main hurdles in effective implementation of e-government services. Along with these limitations, we found that the e-government maturity models adopted by developing countries are failing to provide an appropriate strategic plan to deploy sustainable e-government services. While assessing the existing e-government maturity model, we made several observations on the lack of detail, the technology-centric nature, the emphasis on implementation, and the lack of an adoption strategy. This work contributes toward the proposition of a new e-government maturity model that would address the limitations of exiting e-government maturity models, and would support governments in developing countries to achieve sustainable e-government services. To achieve this goal, we considered five determinants—a detailed process, streamlined services, agile accessibility, use of state-of-the-art technology, and trust and awareness. The proposed model was validated by employing an empirical investigation through case-study and survey methods. We found that both the implementers (government and adopters (users of the e-government services benefited from the proposed model, resulting in an increased sustainability of e-government services.

E-Beam - a new transfer system for isolator technology

International Nuclear Information System (INIS)

Sadat, Theo; Huber, Thomas

2002-01-01

In every aseptic filling application, the sterile transfer of goods into the aseptic area is a challenge, and there are many different ways to do it. With isolator technology a higher sterility assurance level (SAL) is achieved. This SAL is only as good as the weakest segment in the chain of manufacturing. The transfer of goods into and out of the isolator is one of these critical segments. Today different techniques, some already well established, others still very new, are available on the market like: dry heat tunnel, autoclave, pulsed light, rapid transfer systems (RTP), H 2 O 2 tunnel, UV light, etc. all these systems are either not applicable for continuous transfer, only good for heat-compatible materials like glass, or do not guarantee a 6 log spore reduction. E-Beam opens new perspectives in this field. With E-beam technology it is possible to transfer heat-sensitive (plastic), pre-sterilised materials at high speed, continuously into an aseptic area. E-Beam unifies three different technologies, that result in a very efficient and high-speed decontamination machine designed for the pharmaceutical industry. First, there is the electron beam that decontaminates the goods and an accurate shielding that protects the surrounding from this beam. Second, there is the conveyor system that guarantees the output and the correct exposure time underneath the beam. And third, there is the isolator interface to provide correct differential pressure and clean air inside the tunnel as well as the decontamination of the tunnel with H 2 O 2 prior to production. The E-beam is a low-energy electron beam, capable of decontaminating any kind of surface. It penetrates only a few micrometers into the material and therefore does not deform the packaging media. Currently, machines are being built to transfer pre-sterilised syringes, packed in plastic tubs with a Tyvek cover into an aseptic filling isolator with the following data: decontamination efficiency of 10 6 (6 log spore

Boltzmann statistical consideration on the excitation mechanism of iron atomic lines emitted from glow discharge plasmas

International Nuclear Information System (INIS)

Zhang Lei; Kashiwakura, Shunsuke; Wagatsuma, Kazuaki

2011-01-01

A Boltzmann plot for many iron atomic lines having excitation energies of 3.3–6.9 eV was investigated in glow discharge plasmas when argon or neon was employed as the plasma gas. The plot did not show a linear relationship over a wide range of the excitation energy, but showed that the emission lines having higher excitation energies largely deviated from a normal Boltzmann distribution whereas those having low excitation energies (3.3–4.3 eV) well followed it. This result would be derived from an overpopulation among the corresponding energy levels. A probable reason for this is that excitations for the high-lying excited levels would be caused predominantly through a Penning-type collision with the metastable atom of argon or neon, followed by recombination with an electron and then stepwise de-excitations which can populate the excited energy levels just below the ionization limit of iron atom. The non-thermal excitation occurred more actively in the argon plasma rather than the neon plasma, because of a difference in the number density between the argon and the neon metastables. The Boltzmann plots yields important information on the reason why lots of Fe I lines assigned to high-lying excited levels can be emitted from glow discharge plasmas. - Highlights: ► This paper shows the excitation mechanism of Fe I lines from a glow discharge plasma. ► A Boltzmann distribution is studied among iron lines of various excitation levels. ► We find an overpopulation of the high-lying energy levels from the normal distribution. ► It is caused through Penning-type collision of iron atom with argon metastable atom.

Investigation of beam self-polarization in the future e+e− circular collider

CERN Document Server

AUTHOR|(CDS)2075800

2016-10-24

The use of resonant depolarization has been suggested for precise beam energy measurements (better than 100 keV) in the eþe− Future Circular Collider (FCC-eþe−) for Z and WW physics at 45 and 80 GeV beam energy respectively. Longitudinal beam polarization would benefit the Z peak physics program; however it is not essential and therefore it will be not investigated here. In this paper the possibility of selfpolarized leptons is considered. Preliminary results of simulations in presence of quadrupole misalignments and beam position monitors (BPMs) errors for a simplified FCC-eþe− ring are presented.

The Sustainable Role of the E-Trust in the B2C E-Commerce of Vietnam

Directory of Open Access Journals (Sweden)

Yongrok Choi

2018-01-01

Full Text Available Vietnam, as a new emerging market, especially in e-business, has been promoting its emerging e-commerce market in Southeast Asia using aggressive players such as Lazada. Nonetheless, Vietnam has strong cultural background of risk-averse attitudes, like other developing countries, thereby deferring sustainable transformation into the e-business revolution. Therefore, it is necessary to examine the factors leading to the sustainable performance of e-commerce businesses, because highly risk-avert attitudes still cause many problems due to low levels of trust. In this perspective of trust, this research may contribute to promoting Vietnamese online shopping trends and suggesting ways for sustainable business to achieve success in B2C e-commerce. The purpose of this research is to examine whether or not the characteristics of e-service quality (usefulness, convenience, security, responsiveness, and assurance have a positive influence on customer loyalty, one of the sustainable success factors in this growing e-commerce industry in Asian markets. Using questionnaires and structural equation modelling, we concluded that it is crucial to promote e-trust as a vital element, because it lacks, in the short-run, an initial e-trust.

Influence of E-beam irradiation on dielectric relaxation of recycled polypropylene

International Nuclear Information System (INIS)

Fazilova, Z.; Gafurov, U.; Tolstov, A.

2004-01-01

Full text: The dielectric relaxation connected with molecular groups and polymer chain mobility for un-irradiated and e-beam irradiated recycled polypropylene was investigated. It was studied films of samples produced from virgin (initial) and e- beam irradiated of the polymer granules (E-beam source with 5 MeV energy). The dielectric losses were measured with temperature increasing and decreasing regime. The losses were measured with E8-4 bridge help (the frequency is 1kH). Heating velocity was 2 grad/min. The dielectric losses did not appeared in minus temperature region for the initial polypropylene samples. The measurement in temperature increasing and decreasing shows that the relaxation peak at ∼ 35 o C for un-irradiated and ∼70 o C for irradiated polymer samples connected with macromolecular segments mobility with water molecular groups participation. The main relaxation peak (higher 100 o C) shifts after e-beam irradiation is result of the cross-links formation. ) The peak connected with macromolecular segments mobility in polymer amorphous regions (β-relaxation process). In irradiated polypropylene on IR spectroscopy data oxygen molecular groups is increased. The molecular groupings form inter-molecular hydrogen bonds. The intermolecular bonds also hindered molecular groups and macromolecular mobility. The e-beam stimulated cross-links formation was confirmed by method of sol-gel analyses. The work was supported by STCU Fund (Project No 3009)

Gas Breakdown of Radio Frequency Glow Discharges in Helium at near Atmospheric Pressure

International Nuclear Information System (INIS)

Liu Xinkun; Xu Jinzhou; Cui Tongfei; Guo Ying; Zhang Jing; Shi Jianjun

2013-01-01

A one-dimensional self-consistent fluid model was developed for radio frequency glow discharge in helium at near atmospheric pressure, and was employed to study the gas breakdown characteristics in terms of breakdown voltage. The effective secondary electron emission coefficient and the effective electric field for ions were demonstrated to be important for determining the breakdown voltage of radio frequency glow discharge at near atmospheric pressure. The constant of A was estimated to be 64±4 cm −1 Torr −1 , which was proportional to the first Townsend coefficient and could be employed to evaluate the gas breakdown voltage. The reduction in the breakdown voltage of radio frequency glow discharge with excitation frequency was studied and attributed to the electron trapping effect in the discharge gap

Carbon dioxide reforming of methane by atmospheric pressure pulsed glow discharge: The effect of pulse compression

International Nuclear Information System (INIS)

Ghorbanzadeh, A.; Modarresi, H.

2006-01-01

Methane reforming by carbon dioxide in atmospheric pressure pulsed glow discharge was examined. The pulse duration of plasma was compressed to ∼50 ns or lower. This compression allowed working at higher frequencies, more than 3 k Hz, without glow to arc transition. The main outlet gases were synthetic gases (H 2 , CO) and C 2 (ethylene, ethane, and acetylene) products. At equal reactants proportion CO 2 /CH 4 =1, about 42 p ercent o f plasma energy went to chemical dissociation while reactant conversions were relatively high, i.e. near 55 p ercent % (CH 4 ) and 42 p ercent ( CO 2 ). At this point, the energy expenditure was less than 3.8 eV per each converted molecule. The reactor energy performance even gets better at higher CO 2 /CH 4 proportions. At CO 2 /CH 4 =5, The conversions of about 65 p ercent a nd 45 p ercent w ere obtained for methane and carbon dioxide respectively, while energy efficiency reached near 45 p ercent . It is discussed that high nonequilibrium state of vibrational energy at short pulses, especially in carbon dioxide, leads to this improvement.

Acting green elicits a literal warm glow

Science.gov (United States)

Taufik, Danny; Bolderdijk, Jan Willem; Steg, Linda

2015-01-01

Environmental policies are often based on the assumption that people only act environmentally friendly if some extrinsic reward is implicated, usually money. We argue that people might also be motivated by intrinsic rewards: doing the right thing (such as acting environmentally friendly) elicits psychological rewards in the form of positive feelings, a phenomenon known as warm glow. Given the fact that people's psychological state may affect their thermal state, we expected that this warm glow could express itself quite literally: people who act environmentally friendly may perceive the temperature to be higher. In two studies, we found that people who learned they acted environmentally friendly perceived a higher temperature than people who learned they acted environmentally unfriendly. The underlying psychological mechanism pertains to the self-concept: learning you acted environmentally friendly signals to yourself that you are a good person. Together, our studies show that acting environmentally friendly can be psychologically rewarding, suggesting that appealing to intrinsic rewards can be an alternative way to encourage pro-environmental actions.

The e+, e- background at Relativistic Heavy Ion Collider (RHIC) generated by beam crossing

International Nuclear Information System (INIS)

Rhoades-Brown, M.J.; Ludlam, T.; Wu, J.; Bottcher, C.; Strayer, M.

1990-01-01

At the Brookhaven Relativistic Heavy Ion Collider (RHIC), fully stripped heavy ions will circulate in each of two rings up to beam energies of 250 (Z/A) GeV/u. During the beam crossing, the peripheral electromagnetic interaction between the heavy ions is sufficient to induce copious production of di-lepton pairs. These pairs are a potential source of background for the detectors at RHIC. In this paper we discuss the expected number of e + ,e - pairs, given the accepted initial luminosity value L of the collider. More importantly, we also calculate the differential cross sections for the angle, energy, rapidity and momentum distribution of the leptons. Using the luminosity L of the collider, these differential cross sections are normalized to the expected number of leptons per second. We restrict ourselves to e + ,e - production, a discussion of μ + ,μ - and τ + τ - distributions will be published later. The results are presented for the expected worst case, namely 197 Au 79+ ions at a beam kinetic energy of 100 GeV/u. This is forseen to be the heaviest ion for high luminosity experiments at RHIC. We note for a given energy, the cross section for e + ,e - production scales as Z 4 , where Z is the atomic number of the ions

Irradiation of silver and agar/silver nanoparticles with argon, oxygen glow discharge plasma, and mercury lamp.

Science.gov (United States)

Ahmad, Mahmoud M; Abdel-Wahab, Essam A; El-Maaref, A A; Rawway, Mohammed; Shaaban, Essam R

2014-01-01

The irradiation effect of argon, oxygen glow discharge plasma, and mercury lamp on silver and agar/silver nanoparticle samples is studied. The irradiation time dependence of the synthesized silver and agar/silver nanoparticle absorption spectra and their antibacterial effect are studied and compared. In the agar/silver nanoparticle sample, as the irradiation time of argon glow discharge plasma or mercury lamp increases, the peak intensity and the full width at half maximum, FWHM, of the surface plasmon resonance absorption band is increased, however a decrease of the peak intensity with oxygen glow plasma has been observed. In the silver nanoparticle sample, as the irradiation time of argon, oxygen glow discharge plasma or mercury lamp increases, the peak intensity of the surface plasmon resonance absorption band is increased, however, there is no significant change in the FWHM of the surface plasmon resonance absorption band. The SEM results for both samples showed nanoparticle formation with mean size about 50 nm and 40 nm respectively. Throughout the irradiation time with the argon, oxygen glow discharge plasma or mercury lamp, the antibacterial activity of several kinds of Gram-positive and Gram-negative bacteria has been examined.

Correlation between TL and OSL signals in KMgF3:Ce3+: Bleaching study of individual glow-peaks

International Nuclear Information System (INIS)

Dallas, G.I.; Polymeris, G.S.; Afouxenidis, D.; Tsirliganis, N.C.; Tsagas, N.F.; Kitis, G.

2010-01-01

KMgF 3 :Ce 3+ is an ultra sensitive Thermoluminescence (TL) material with a complex TL and OSL glow-curve structure. The aim of the present work is to attempt a one-to-one correspondence between specific TL glow-peaks and OSL components in KMgF 3 :Ce 3+ . The correlation study involves the deconvolution of the TL curves and the estimation of the bleaching decay constants for individual glow-peaks followed by the deconvolution of the LM-OSL curve using the estimated decay constants. It was found that the bleaching of each individual glow-peak takes place in three different rates; namely in a fast, medium and slow rate.

Glow phenomenon surrounding the vertical stabilizer and OMS pods

Science.gov (United States)

1994-01-01

This 35mm frame, photographed as the Space Shuttle Columbia was orbiting Earth during a 'night' pass, documents the glow phenomenon surrounding the vertical stabilizer and the Orbital Maneuvering System (OMS) pods of the spacecraft.

Surface characterization after subaperture reactive ion beam etching

Energy Technology Data Exchange (ETDEWEB)

Miessler, Andre; Arnold, Thomas; Rauschenbach, Bernd [Leibniz-Institut fuer Oberflaechenmodifizierung (IOM), Leipzig (Germany)

2010-07-01

In usual ion beam etching processes using inert gas (Ar, Xe, Kr..) the material removal is determined by physical sputtering effects on the surface. The admixture of suitable gases (CF{sub 4}+O{sub 2}) into the glow discharge of the ion beam source leads to the generation of reactive particles, which are accelerated towards the substrate where they enhance the sputtering process by formation of volatile chemical reaction products. During the last two decades research in Reactive Ion Beam Etching (RIBE) has been done using a broad beam ion source which allows the treatment of smaller samples (diameter sample < diameter beam). Our goal was to apply a sub-aperture Kaufman-type ion source in combination with an applicative movement of the sample with respect to the source, which enables us to etch areas larger than the typical lateral dimensions of the ion beam. Concerning this matter, the etching behavior in the beam periphery plays a decisive role and has to be investigated. We use interferometry to characterize the final surface topography and XPS measurements to analyze the chemical composition of the samples after RIBE.

On the choice of beam polarization in e{sup +}e{sup -} → ZZ/Zγ and anomalous triple gauge-boson couplings

Energy Technology Data Exchange (ETDEWEB)

Rahaman, Rafiqul; Singh, Ritesh K. [Indian Institute of Science Education and Research Kolkata, Department of Physical Sciences, Mohanpur (India)

2017-08-15

The anomalous trilinear gauge couplings of Z and γ are studied in e{sup +}e{sup -} → ZZ/Zγ with longitudinal beam polarizations using a complete set of polarization asymmetries for the Z boson. We quantify the goodness of the beam polarization in terms of the likelihood and find the best choice of e{sup -} and e{sup +} polarizations to be (+0.16, -0.16), (+0.09, -0.10) and (+0.12, -0.12) for ZZ, Zγ and combined processes, respectively. Simultaneous limits on anomalous couplings are obtained for these choices of beam polarizations using Markov-Chain-Monte-Carlo (MCMC) for an e{sup +}e{sup -} collider running at √(s) = 500 GeV and L = 100 fb{sup -1}. We find the simultaneous limits for these beam polarizations to be comparable with each other and also comparable with the unpolarized beam case. (orig.)

E-beam treatment of trichloroethylene-air mixtures: products and rates

International Nuclear Information System (INIS)

Mill, Theodore; Minggong Su; Yao, C.C.D.; Matthews, S.M.; Wang, F.T.S.

1997-01-01

Electron beam (E-beam) treatment of 3000 ppmv trichloroethylene (TCE) vapor in dry and wet air led to rapid, nearly quantitative, conversion of TCE to dichloroacetyl chloride, plus small amounts of phosgene. Higher E-beam dose, up to 110 kGy, led to oxidation of the initial products to CO, CO 2 , HCl and Cl 2 . The results parallel results found for photo- and Cl-atom initiated oxidation of TCE vapor, and are accounted for by an efficient Cl-atom chain oxidation. Lack of effect of 28,000 ppmv water vapor (90% RH) on rates or products reflects a very high efficiency for the Cl-atom chain oxidation and the very slow reaction of vapor phase water with acyl halides. Irradiation experiments conducted with TCE dissolved in aerated and deaerated water at 10 and 300 ppm showed marked differences in radiolytic products from those found in the vapor phase. A preliminary cost estimate indicates that E-beam treatment of TCE vapor is very competitive with conventional activated carbon treatment and catalytic oxidation. (author)

Computerized glow curve deconvolution of thermoluminescent emission from polyminerals of Jamaica Mexican flower

Science.gov (United States)

Favalli, A.; Furetta, C.; Zaragoza, E. Cruz; Reyes, A.

The aim of this work is to study the main thermoluminescence (TL) characteristics of the inorganic polyminerals extracted from dehydrated Jamaica flower or roselle (Hibiscus sabdariffa L.) belonging to Malvaceae family of Mexican origin. TL emission properties of the polymineral fraction in powder were studied using the initial rise (IR) method. The complex structure and kinetic parameters of the glow curves have been analysed accurately using the computerized glow curve deconvolution (CGCD) assuming an exponential distribution of trapping levels. The extension of the IR method to the case of a continuous and exponential distribution of traps is reported, such as the derivation of the TL glow curve deconvolution functions for continuous trap distribution. CGCD is performed both in the case of frequency factor, s, temperature independent, and in the case with the s function of temperature.

The Sustainable Role of the E-Trust in the B2C E-Commerce of Vietnam

OpenAIRE

Yongrok Choi; Do Quynh Mai

2018-01-01

Vietnam, as a new emerging market, especially in e-business, has been promoting its emerging e-commerce market in Southeast Asia using aggressive players such as Lazada. Nonetheless, Vietnam has strong cultural background of risk-averse attitudes, like other developing countries, thereby deferring sustainable transformation into the e-business revolution. Therefore, it is necessary to examine the factors leading to the sustainable performance of e-commerce businesses, because highly risk-aver...

Boltzmann statistical consideration on the excitation mechanism of iron atomic lines emitted from glow discharge plasmas

Energy Technology Data Exchange (ETDEWEB)

Zhang Lei; Kashiwakura, Shunsuke; Wagatsuma, Kazuaki, E-mail: wagatuma@imr.tohoku.ac.jp

2011-11-15

A Boltzmann plot for many iron atomic lines having excitation energies of 3.3-6.9 eV was investigated in glow discharge plasmas when argon or neon was employed as the plasma gas. The plot did not show a linear relationship over a wide range of the excitation energy, but showed that the emission lines having higher excitation energies largely deviated from a normal Boltzmann distribution whereas those having low excitation energies (3.3-4.3 eV) well followed it. This result would be derived from an overpopulation among the corresponding energy levels. A probable reason for this is that excitations for the high-lying excited levels would be caused predominantly through a Penning-type collision with the metastable atom of argon or neon, followed by recombination with an electron and then stepwise de-excitations which can populate the excited energy levels just below the ionization limit of iron atom. The non-thermal excitation occurred more actively in the argon plasma rather than the neon plasma, because of a difference in the number density between the argon and the neon metastables. The Boltzmann plots yields important information on the reason why lots of Fe I lines assigned to high-lying excited levels can be emitted from glow discharge plasmas. - Highlights: Black-Right-Pointing-Pointer This paper shows the excitation mechanism of Fe I lines from a glow discharge plasma. Black-Right-Pointing-Pointer A Boltzmann distribution is studied among iron lines of various excitation levels. Black-Right-Pointing-Pointer We find an overpopulation of the high-lying energy levels from the normal distribution. Black-Right-Pointing-Pointer It is caused through Penning-type collision of iron atom with argon metastable atom.

Characterization and switching performance of electron-beam controlled discharges

International Nuclear Information System (INIS)

Lowry, J.F.; Kline, L.E.; Heberlein, J.V.R.

1986-01-01

The electron-beam sustained discharge switch is an attractive concept for repetitive pulsed power switching because it has a demonstrated capability to interrupt direct current and because it is inherently scalable. The authors report on experiments with this type of switch in a 4-kV dc circuit. A wire-ion-plasma (WIP) electron-beam (e-beam) gun is used to irradiate and sustain a switch discharge with a 100-cm/sup 2/ cross-sectional area in l atm of N/sub 2/ or CH/sub 4/. Interruption of 8-10-μs pulses of up to 1.9 kA, and of 100-μs pulses of 150 A has been demonstrated in methane, and interruption against higher recovery voltages (11 kV) has been performed at 1.2 kA by adding series inductance to the circuit. These values represent power supply limitations rather than limitations of the switch itself. A comparison of the measured discharge characteristics with theoretical predictions shows that the measured switch conductivities are higher than the predicted values for given e-beam current values. A qualitative explanation for this observation is offered by considering the effects of electron reflection from the discharge anode and of nonlinear paths for the beam electrons across the discharge gap. The authors conclude that the switching performance of the e-beam controlled discharge switch corresponds to its design parameters, and that for a given switch size a lower voltage drop during the on time can be expected compared with the voltage drop predicted by previously published theory

Design and experiment of high-current low-pressure plasma-cathode e-gun

International Nuclear Information System (INIS)

Xie Wenkai; Li Xiaoyun; Wang Bin; Meng Lin; Yan Yang; Gao Xinyan

2006-01-01

The preliminary design of a new high-power low pressure plasma-cathode e-gun is presented. Based on the hollow cathode effect and low-pressure glow discharge empirical formulas, the hollow cathode, the accelerating gap, and the working gas pressure region are given. The general experimental device of the low-pressure plasma cathode electron-gun generating high current density e-beam source is shown. Experiments has been done in continuous filled-in gases and gases-puff condition, and the discharging current of 150-200 A, the width of 60 μs and the collector current of 30-80 A, the width of 60 μs are obtained. The results show that the new plasma cathode e-gun can take the place of material cathode e-gun, especially in plasma filled microwave tubes. (authors)

Altruism, warm glow, and charitable giving: Three experiments

NARCIS (Netherlands)

Bekkers, R.H.F.P.; Ottoni-Wilhelm, M.; Verkaik, D.J.

2015-01-01

One of the key questions in the science of philanthropy is to what extent donations to charity are motivated by altruism – concern for public benefits, including the well-being of recipients – and warm glow – concerns for private benefits, including emotional gratification. To disentangle altruism

Removal of a glowing spot from an image tube using laser radiation.

Science.gov (United States)

Gurski, T. R.

1972-01-01

A troublesome problem with the Kron electronograph has been the presence of a white glowing spot on the glass wall of the tube adjacent to the focus electrode. The procedure followed to eliminate the spot was to operate in the dark and apply voltage only to the focused electrode. Ruby laser radiation was unfocused, and its position was shifted on the electrode between laser shots until an effect was observed. This technique for removing the glowing spot should be applicable to other electronic image tubes.

Binary and ternary gas mixtures for use in glow discharge closing switches

Science.gov (United States)

Hunter, S.R.; Christophorou, L.G.

1988-04-27

Highly efficient binary and ternary gas mixtures for use in diffuse glow discharge closing switches are disclosed. The binary mixtures are combinations of helium or neon and selected perfluorides. The ternary mixtures are combinations of helium, neon, or argon, a selected perfluoride, and a small amount of gas that exhibits enhanced ionization characteristics. These mixtures are shown to be the optimum choices for use in diffuse glow discharge closing switches by virtue if the combines physio-electric properties of the mixture components. 9 figs.

E-Waste and the Sustainable Organisation: Griffith University's Approach to E-Waste

Science.gov (United States)

Davis, Georgina; Wolski, Malcolm

2009-01-01

Purpose: This paper seeks to provide details of Griffith University's (GU) approach for sustainably dealing with electronic waste (e-waste) and the benefits of using the e-waste programme as a valuable educational case study for ESD. Design/methodology/approach: The e-waste programme is explained with reference to key resources and literature, so…

The characteristics of epoxy resin cured by {gamma}-ray and E-beam

Energy Technology Data Exchange (ETDEWEB)

Nho, Y.C. E-mail: ycnho@kaeri.re.kr; Kang, Phil Hyun; Park, Jong Seok

2004-10-01

Epoxy resins are widely used as high-performance thermosetting resins for many industrial applications. In this study, the effect of an electron beam (E-beam) and {gamma}-ray irradiation on the curing of epoxy resins was investigated. Diglycidyl ether of bisphenol-A(DGEBA), diglycidyl ether of bisphenol-F(DGEBF) as epoxy resins, triarylsulfonium hexafluoroantimonate(TASHFA), and triarylsulfonium hexafluorophosphate(TASHFP) as initiators were used in this study. The chemical and mechanical characteristics of irradiated epoxy resins were compared after curing of E-beam and {gamma}-ray irradiation up to 50 kGy in N{sub 2} and air atmosphere. We ascertained the effect of oxygen on the radiation curing of epoxy resin. The thermal properties of cured epoxy were investigated using DMA and TGA. Mechanical properties such as flexural strength were measured. The chemical structures of cured epoxy were characterized by FT-NIR. The gel fraction and the stress at yield of epoxy resins irradiated by E-beam and {gamma}-ray in N{sub 2} atmosphere were also compared with those of epoxy resins irradiated by E-beam and {gamma}-ray in air.

A new e-beam application in the pharmaceutical industry

International Nuclear Information System (INIS)

Sadat, Theo; Malcolm, Fiona

2005-01-01

The paper presents a new electron beam application in the pharmaceutical industry: an in-line self-shielded atropic transfer system using electron beam for surface decontamination of products entering a pharmaceutical filling line. The unit was developed by Linac Technologies in response to the specifications of a multi-national pharmaceutical company, to solve the risk of microbial contamination entering a filling line housed inside an isolator. In order to fit the sterilization unit inside the pharmaceutical plant, a 'miniature' low-energy (200 keV) electron beam accelerator and e-beam tunnel were designed, all conforming to the pharmaceutical good manufacturing practice (GMP) regulations. Process validation using biological indicators is described, with reference to the regulations governing the pharmaceutical industry. Other industrial applications of a small-sized self-shielded electron beam sterilization unit are mentioned

Formation and sustainment of field reversed configuration (FRC) plasmas by spheromak merging and neutral beam injection

Energy Technology Data Exchange (ETDEWEB)

Yamada, Masaaki [Princeton Plasma Physics Laboratory, Princeton University Princeton, New Jersey USA (United States)

2016-03-25

This paper briefly reviews a compact toroid reactor concept that addresses critical issues for forming, stabilizing and sustaining a field reversed configuration (FRC) with the use of plasma merging, plasma shaping, conducting shells, neutral beam injection (NBI). In this concept, an FRC plasma is generated by the merging of counter-helicity spheromaks produced by inductive discharges and sustained by the use of neutral beam injection (NBI). Plasma shaping, conducting shells, and the NBI would provide stabilization to global MHD modes. Although a specific FRC reactor design is outside the scope of the present paper, an example of a promising FRC reactor program is summarized based on the previously developed SPIRIT (Self-organized Plasmas by Induction, Reconnection and Injection Techniques) concept in order to connect this concept to the recently achieved the High Performance FRC plasmas obtained by Tri Alpha Energy [Binderbauer et al, Phys. Plasmas 22,056110, (2015)]. This paper includes a brief summary of the previous concept paper by M. Yamada et al, Plasma Fusion Res. 2, 004 (2007) and the recent experimental results from MRX.

Time effectiveness of capillary effect improvement of ramie fabrics processed by RF glow discharging

International Nuclear Information System (INIS)

Wang Zhiwen; Wei Weixing; He Yanhe; Zhao Yuanqing; Pan Liyiji; Li Xuemei; Shi Shaodui; Li Guangxin

2010-01-01

The time effectiveness of capillary effect improvement of ramie fabrics processed by RF glow discharging was studied. The ramie fabrics were processed in fulfilling with different gas (O 2 , N 2 , Ar) by different parameters (such as pressure,power and time) plasma. The capillary effect of the ramie fabrics processed by RF glow discharging was tested at different time. The results indicate that the capillary effect of ramie fabrics processed by RF glow discharging has been improved, the improvement of the capillary effect firstly decrease rapidly, then slowly, and become stable after 15 day, it indicate that improvement of the ramie fabrics capillary has good time effectiveness, and the plasma parameter for the best capillary effect improvement of ramie fabric is 100 W and 40 Pa processed 20 min by oxygen plasma. (authors)

Detrapping of tungsten nanoparticles in a direct-current argon glow discharge

Energy Technology Data Exchange (ETDEWEB)

Couëdel, L., E-mail: lenaic.couedel@univ-amu.fr; Kumar, K. Kishor; Arnas, C. [Laboratoire de Physique des Interactions Ioniques et Moléculaires, CNRS, Aix-Marseille Université, 13397 Marseille (France)

2014-12-15

Nanoparticles are grown from the sputtering of a tungsten cathode in a direct current argon glow discharge. Laser light scattering of a vertical laser sheet going through the plasma reveals that the dust particle cloud is compressed and pushed towards the anode during the discharge. Scanning electron microscopy images of substrates exposed to the plasma for given durations show that dust particles are continuously falling down on the anode during the discharge. These observations are explained by the fact that the electrostatic force at the negative glow-anode sheath boundary cannot balance the ion drag, gravity, and thermophoresis forces for particles of more than a few tens of nanometres in diameter.

Periodic long-range transport in a large volume dc glow discharge dusty plasma

International Nuclear Information System (INIS)

Thomas, Edward Jr.; Amatucci, William E.; Compton, Christopher; Christy, Brian; Jackson, Jon David

2003-01-01

In an earlier paper, the authors reported on observations of a variety of particle transport phenomena observed in DUPLEX--the DUsty PLasma EXperiment at the Naval Research Laboratory [E. Thomas, Jr., W. E. Amatucci, C. Compton, and B. Christy, Phys. Plasmas 9, 3154 (2002)]. DUPLEX is a large, transparent polycarbonate cylinder that is 40 cm in radius and 80 cm in height. dc glow discharge argon plasmas are generated in DUPLEX. In this paper, the authors expand upon one particular feature of particle transport in DUPLEX, the long-range (i.e., greater than 15 cm), periodic (T∼2.5 min) transport of suspended alumina particles through the plasma. A detailed description of this particle motion through the plasma is presented. Finally, a qualitative model describing the phenomena that lead to this transport is also given

On the economic sustainability of ethanol E85

International Nuclear Information System (INIS)

Tatum, Shaun W.; Skinner, Sarah J.; Jackson, John D.

2010-01-01

Several studies have considered the sustainability of corn-based ethanol as produced in the US as a major fuel source from a technical perspective. However, not much attention has been paid to the market-based aspects of corn-based ethanol as a sustainable fuel. We address this question by offering an econometric analysis of the E85 (apparently the most viable of the potential substitutes for gasoline) market using demand and supply analysis. Reduced form price equation estimates indicate that the cross elasticity of E85's price with respect to the price of gasoline does not differ significantly from unity, so that any rise in gasoline prices will be matched (in percentage terms) by a corresponding rise in the price of E85. Thus, given the current market, which includes significant government subsidy, the prospect that E85 will ever be price competitive with gasoline is indeed dim. (author)

On the economic sustainability of ethanol E85

Energy Technology Data Exchange (ETDEWEB)

Tatum, Shaun W.; Skinner, Sarah J.; Jackson, John D.

2010-11-15

Several studies have considered the sustainability of corn-based ethanol as produced in the US as a major fuel source from a technical perspective. However, not much attention has been paid to the market-based aspects of corn-based ethanol as a sustainable fuel. We address this question by offering an econometric analysis of the E85 (apparently the most viable of the potential substitutes for gasoline) market using demand and supply analysis. Reduced form price equation estimates indicate that the cross elasticity of E85's price with respect to the price of gasoline does not differ significantly from unity, so that any rise in gasoline prices will be matched (in percentage terms) by a corresponding rise in the price of E85. Thus, given the current market, which includes significant government subsidy, the prospect that E85 will ever be price competitive with gasoline is indeed dim. (author)

Development of a Beam Trajectory Monitoring System Using e+/e- Pair Production Events

Science.gov (United States)

Kimura, Shota; Emoto, Yusaku; Fujihara, Kento; Ito, Hiroshi; Kawai, Hideyuki; Kobayashi, Atsushi; Mizuno, Takahiro

2018-01-01

In particle therapy, it is important to monitor the Bragg-peak position. It was simulated by GEANT4 Monte Carlo Simulation Code that the distribution of secondary generated gamma rays on the carbon beam therapy and the proton beam therapy. This simulation shows that gamma rays whose energy is 10 MeV or more are intensively generated at the Bragg-peak position. We are developing the system to monitor the Bragg-peak position which can measure pair production events occurred in the detector by gamma rays from irradiation points. The momentum direction of the gamma ray can be determined by measuring passing points and energy of e+ and e- generated by pair production. This system has 5 parts. The first is the conversion part. This part consists of several layers. Each layer is composed of a La-GPS ((Gd0.75La0.24Ce0.01)2Si2O7) scintillator plate and wavelength-shifting fibre (WLSF) sheets. The scintillator plate is sandwiched between sheets, where the directions of the sheets are in orthogonally x and y directions. In this part, gamma rays are converted to e+ e- pairs and the position where the conversion occured is determined. The second is the tracking part. This part consists of 2 layers of scintillating fibre tracker. Each layer has 6 scintillating fibre sheets for x, x', u, u', v, and v'. The third is the energy measurement part. It measures the energy of e+ and e- by scintillator array and Silicon Photomultipliers. The fourth is the veto counter for bremsstrahlung gamma rays from e+ and e-. The fifth is the beam monitor. By experiment, the number of photoelectrons of La-GPS with a WLSF (B-3(300)MJ, Kuraray) sheet and scintillating fibre (SCSF-78, Kuraray) when charged particle passed was measured as 9.7 and 7.6 respectively.

Trajectories of Attaining and Sustaining Quality in E-learning ...

African Journals Online (AJOL)

Trajectories of Attaining and Sustaining Quality in E-learning. ... Log in or Register to get access to full text downloads. ... Experts must be employed who will evaluate appropriateness of e-learning procedures, accuracy of e-learning content ...

Effects of carbon wall on the behavior of Heliotron-E plasmas

Energy Technology Data Exchange (ETDEWEB)

Noda, N; Mizuuchi, T; Akaishi, K; Senju, T; Kondo, K; Kaneko, H; Motojima, O; Baba, T; Besshou, S; Sato, M

1989-04-01

Carbonization was successfully applied to Heliotron-E. Iron-inpurity radiations were strongly reduced with the carbonized wall. Main impacts of the metal reduction on plasma behaviors are sustainment of stored energy during high power, long pulse heating by NBI, achievement of a quasi-steady discharge with a low helical field and high beta, and highest electron density with pellet injection in a quasi-steady state. Hydrogen recycling was very high with the carbonized wall and low density operation was impossible. Helium glow discharge was found to be effective to control the hydrogen recycling with a carbon-tiled wall. (orig.).

Glow discharge based device for solving mazes

Energy Technology Data Exchange (ETDEWEB)

Dubinov, Alexander E., E-mail: dubinov-ae@yandex.ru; Mironenko, Maxim S.; Selemir, Victor D. [Russian Federal Nuclear Center − All-Russian Scientific and Research Institute of Experimental Physics (RFNC-VNIIEF), Sarov, Nizhni Novgorod region 607188 (Russian Federation); Sarov Institute of Physics and Technology (SarFTI) of National Research Nuclear University “MEPhI,” Sarov, Nizhni Novgorod region 607188 (Russian Federation); Maksimov, Artem N.; Pylayev, Nikolay A. [Russian Federal Nuclear Center − All-Russian Scientific and Research Institute of Experimental Physics (RFNC-VNIIEF), Sarov, Nizhni Novgorod region 607188 (Russian Federation)

2014-09-15

A glow discharge based device for solving mazes has been designed and tested. The device consists of a gas discharge chamber and maze-transformer of radial-azimuth type. It allows changing of the maze pattern in a short period of time (within several minutes). The device has been tested with low pressure air. Once switched on, a glow discharge has been shown to find the shortest way through the maze from the very first attempt, even if there is a section with potential barrier for electrons on the way. It has been found that ionization waves (striations) can be excited in the maze along the length of the plasma channel. The dependancy of discharge voltage on the length of the optimal path through the maze has been measured. A reduction in discharge voltage with one or two potential barriers present has been found and explained. The dependency of the magnitude of discharge ignition voltage on the length of the optimal path through the maze has been measured. The reduction of the ignition voltage with the presence of one or two potential barriers has been observed and explained.

E3: Economy - Energy - Environment; Supporting Manufacturing Leadership through Sustainability

Data.gov (United States)

U.S. Environmental Protection Agency — The E3 initiative is designed to help you thrive in a new business era focused on sustainability and, working together, to promote sustainable manufacturing and...

An Investigation of LED Street Lighting's Impact on Sky Glow

Energy Technology Data Exchange (ETDEWEB)

Kinzey, Bruce R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Perrin, Tess E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Miller, Naomi J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kocifaj, Miroslav [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Aube, Martin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lamphar, Hector A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2017-04-25

A significant amount of public attention has recently focused on perceived impacts of converting street lighting from incumbent lamp-based products to LED technology. Much of this attention pertains to the higher content of short wavelength light (commonly referred to as "blue light") of LEDs and its attendant influences on sky glow (a brightening of the night sky that can interfere with astronomical observation and may be associated with a host of other issues). The complexity of this topic leads to common misunderstandings and misperceptions among the public, and for this reason the U.S. Department of Energy Solid-State Lighting Program embarked on a study of sky glow using a well-established astronomical model to investigate some of the primary factors influencing sky glow. This report details the results of the investigation and attempts to present those results in terms accessible to the general lighting community. The report also strives to put the results into a larger context, and help educate interested readers on various topics relevant to the issues being discussed.

The back-diffusion effect of air on the discharge characteristics of atmospheric-pressure radio-frequency glow discharges using bare metal electrodes

International Nuclear Information System (INIS)

Sun Wenting; Liang Tianran; Wang Huabo; Li Heping; Bao Chengyu

2007-01-01

Radio-frequency (RF), atmospheric-pressure glow discharge (APGD) plasmas using bare metal electrodes have promising prospects in the fields of plasma-aided etching, deposition, surface treatment, disinfection, sterilization, etc. In this paper, the discharge characteristics, including the breakdown voltage and the discharge voltage for sustaining a stable and uniform α mode discharge of the RF APGD plasmas are presented. The experiments are conducted by placing the home-made planar-type plasma generator in ambient and in a vacuum chamber, respectively, with helium as the primary plasma-forming gas. When the discharge processes occur in ambient, particularly for the lower plasma-working gas flow rates, the experimental measurements show that it is the back-diffusion effect of air in atmosphere, instead of the flow rate of the gas, that results in the obvious decrease in the breakdown voltage with increasing plasma-working gas flow rate. Further studies on the discharge characteristics, e.g. the luminous structures, the concentrations and distributions of chemically active species in plasmas, with different plasma-working gases or gas mixtures need to be conducted in future work

Thermoluminescence and glow curves analysis of γ-exposed Eu3+ doped K3Y(PO4)2 nanophosphors

International Nuclear Information System (INIS)

Gupta, Palvi; Bedyal, A.K.; Kumar, Vinay; Singh, Vivek K.; Khajuria, Y.; Ntwaeaborwa, O.M.; Swart, H.C.

2016-01-01

Highlights: • First time, a detailed comparative study of the glow curves and kinetic parameters was made on K 3 Y(PO 4 ) 2 nanophosphor. • Combustion method was employed to synthesize the Eu 3+ doped K 3 Y(PO 4 ) 2 nanophosphor. • The nanophosphor exhibited sublinear response suggesting that it is suitable for TL dosimetry. - Abstract: Eu 3+ doped K 3 Y(PO 4 ) 2 nanophosphor was synthesized by combustion synthesis using urea as a fuel. The crystal structure and particle morphology of the nanophosphor were investigated by using X-ray diffraction and transmission electron microscopy, respectively. A Thermoluminescence (TL) study was carried out after exposing the samples to gamma radiation. The TL glow curves exhibited a prominent peak at 407 K and a small hump at 478 K. The intensity of the peaks increased with the increase in the dose of the gamma rays (0.01–5 kGy). The K 3 Y(PO 4 ) 2 : Eu 3+ (2.5 mol%) nanophosphor exhibited sublinear TL response to γ-radiation over a wide range of gamma doses (0.01–5 kGy). The TLanal program was used to analyze the glow curves of the K 3 Y(PO 4 ) 2 nanophosphor at different doses (0.2–5 kGy) and different heating rates (3–10 K/s). A comparative study was done for kinetic trapping parameters that were determined by the peak shape methods of Chen, Grossweiner and Lushchik. The frequency factors (s) for each glow peak were also calculated. The values of the activation energy (E) obtained by the TLanal program were in good agreement with those obtained by the peak shape methods. The effect of different amount of doses and different heating rates are discussed.

Study of plasma characteristics in the cathode regime of a nitrogen glow discharge

International Nuclear Information System (INIS)

Margulis, Alvaro

1987-01-01

This research thesis reports the study of the cathode region, cathodic sheath and negative glow, of a nitrogen glow discharge. The author first presents general data regarding glow discharges, a description of the experimental installation, and measurements of discharge balancing. In the next part, he precisely describes spectroscopic methods, and the implementation of diagnoses from an experimental point of view as well as in terms of space resolution. Results are then presented and interpreted. Measurements concern space distributions of excited species, the determination of axial and radial concentrations of nitrogen ions, axial variations of rotational temperatures of the different species and variations of nitrogen ion vibrational temperature. The laser optogalvanic effect on the nitrogen molecular ion is resolved in time, and compared with the result of a theoretical model based on the mobility difference between the different nitrogen ions. Finally, the author compares experimental results on ion profiles along the discharge axis with results obtained with theoretical models [fr

Ignition Features of Plasma-Beam Discharge in Gas-Discharge Electron Gun Operation

Directory of Open Access Journals (Sweden)

Valery A. Tutyk

2013-01-01

Full Text Available The current paper presents the results of experimental researches to determine the mode features of plasma-beam discharge (PBD generation by an electron beam injected by a low-vacuum gasdischarge electron gun (LGEG with the cold cathode and hollow anode on the basis of the high-voltage glow discharge and in the range of helium pressure of P ? 10 ÷ 130 Pa. The PBD boundaries and their dependences on parameters of an electron beam are found. The influence of PBD on parameters of low-vacuum gas-discharge electron gun is revealed. It causes an avalanche increase of electron beam current and burning of plasma-beam discharge in the whole space of the vacuum chamber volume and generation of electromagnetic radiation is revealed. Achieved results will be used for implementation of various vacuum technologies in the medium of reaction gas and generated electromagnetic radiation.

Observation of bifurcation phenomena in an electron beam plasma system

International Nuclear Information System (INIS)

Hayashi, N.; Tanaka, M.; Shinohara, S.; Kawai, Y.

1995-01-01

When an electron beam is injected into a plasma, unstable waves are excited spontaneously near the electron plasma frequency f pe by the electron beam plasma instability. The experiment on subharmonics in an electron beam plasma system was performed with a glow discharge tube. The bifurcation of unstable waves with the electron plasma frequency f pe and 1/2 f pe was observed using a double-plasma device. Furthermore, the period doubling route to chaos around the ion plasma frequency in an electron beam plasma system was reported. However, the physical mechanism of bifurcation phenomena in an electron beam plasma system has not been clarified so far. We have studied nonlinear behaviors of the electron beam plasma instability. It was found that there are some cases: the fundamental unstable waves and subharmonics of 2 period are excited by the electron beam plasma instability, the fundamental unstable waves and subharmonics of 3 period are excited. In this paper, we measured the energy distribution functions of electrons and the dispersion relation of test waves in order to examine the physical mechanism of bifurcation phenomena in an electron beam plasma system

Setting-up of the Laser Induced Fluorescence diagnostic. Measurements of Cr density in a neon glow discharge

International Nuclear Information System (INIS)

Tafalla, D.; Cal, E. de la; Tabares, F.L.

1994-01-01

A plasma diagnostic based on the Laser Induced Fluorescence (LIF) technique has been set up in the Fusion Division at the CIEMAT. In a preliminary experiment, The density of sputtered chromium atoms produced in a neon glow discharge was measured. Firstly, the laser beam was characterized by calibration of its wavelength bandwidth and energy profile and Rayleigh scattering in N 2 was used for the optical system calibration. An absolute density of Cr atoms of n= 5x10''9 cm''-3 was obtained in discharges at 100 mA and pressure of 15 mTorr and a linear dependence of the LIF signal US. current was found. These values are in agreement with those expected from the tabulated sputtering yields and the thermalization and diffusion of the sputtered atoms into the Ne plasma

Transitions between corona, glow, and spark regimes of nanosecond repetitively pulsed discharges in air at atmospheric pressure

Science.gov (United States)

Pai, David Z.; Lacoste, Deanna A.; Laux, Christophe O.

2010-05-01

In atmospheric pressure air preheated from 300 to 1000 K, the nanosecond repetitively pulsed (NRP) method has been used to generate corona, glow, and spark discharges. Experiments have been performed to determine the parameter space (applied voltage, pulse repetition frequency, ambient gas temperature, and interelectrode gap distance) of each discharge regime. In particular, the experimental conditions necessary for the glow regime of NRP discharges have been determined, with the notable result that there exists a minimum and maximum gap distance for its existence at a given ambient gas temperature. The minimum gap distance increases with decreasing gas temperature, whereas the maximum does not vary appreciably. To explain the experimental results, an analytical model is developed to explain the corona-to-glow (C-G) and glow-to-spark (G-S) transitions. The C-G transition is analyzed in terms of the avalanche-to-streamer transition and the breakdown field during the conduction phase following the establishment of a conducting channel across the discharge gap. The G-S transition is determined by the thermal ionization instability, and we show analytically that this transition occurs at a certain reduced electric field for the NRP discharges studied here. This model shows that the electrode geometry plays an important role in the existence of the NRP glow regime at a given gas temperature. We derive a criterion for the existence of the NRP glow regime as a function of the ambient gas temperature, pulse repetition frequency, electrode radius of curvature, and interelectrode gap distance.

Electric probe data analysis for glow discharge diagnostics

International Nuclear Information System (INIS)

Cain, B.L.

1987-01-01

This report summarizes the development and application of digital computations for the analysis of data from an electric probe used for glow discharge diagnostics. The essential physics of the probe/discharge interaction is presented, along with formulations from modern electric probe theory. These results are then digitally implemented by a set of computer programs which both calculate discharge properties of electron temperature and density, and aid in the interpretation of these property estimates. The method of analysis, and the theories selected for implementation, are valid only for low pressure, collisionless sheath, and quiescent discharges where the single electric probe has a much smaller area than the discharge reference electrode. However, certain algorithms are included which, in some cases, can extend the analysis into intermediate pressure regimes. The digital programs' functional capabilities are demonstrated by the analysis of experimental probe data, collected using a laboratory glow discharge. Typical sources of error inherent in the electric probe method are discussed, along with an analysis of error induced by the computational methods of the programs. 27 refs., 49 figs., 20 tabs

Vertical beam size measurement in the CESR-TA e{sup +}e{sup −} storage ring using x-rays from synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Alexander, J.P.; Chatterjee, A.; Conolly, C.; Edwards, E.; Ehrlichman, M.P.; Fontes, E. [Cornell University, Ithaca, NY 14853 (United States); Heltsley, B.K., E-mail: bkh2@cornell.edu [Cornell University, Ithaca, NY 14853 (United States); Hopkins, W.; Lyndaker, A.; Peterson, D.P.; Rider, N.T.; Rubin, D.L.; Savino, J.; Seeley, R.; Shanks, J. [Cornell University, Ithaca, NY 14853 (United States); Flanagan, J.W. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan)

2014-06-01

We describe the construction and operation of an X-ray beam size monitor (xBSM), a device measuring e{sup +} and e{sup −} beam sizes in the CESR-TA storage ring using synchrotron radiation. The device can measure vertical beam sizes of 10–100μm on a turn-by-turn, bunch-by-bunch basis at e{sup ±} beam energies of ∼2GeV. At such beam energies the xBSM images X-rays of ϵ≈1–10keV (λ≈0.1–1nm) that emerge from a hard-bend magnet through a single- or multiple-slit (coded aperture) optical element onto an array of 32 InGaAs photodiodes with 50μm pitch. Beamlines and detectors are entirely in-vacuum, enabling single-shot beam size measurement down to below 0.1 mA (2.5×10{sup 9} particles) per bunch and inter-bunch spacing of as little as 4 ns. At E{sub b}=2.1GeV, systematic precision of ∼1μm is achieved for a beam size of ∼12μm; this is expected to scale as ∝1/σ{sub b} and ∝1/E{sub b}. Achieving this precision requires comprehensive alignment and calibration of the detector, optical elements, and X-ray beam. Data from the xBSM have been used to extract characteristics of beam oscillations on long and short timescales, and to make detailed studies of low-emittance tuning, intra-beam scattering, electron cloud effects, and multi-bunch instabilities.

Weak interaction effects in e+e- annihilation with polarised beams

International Nuclear Information System (INIS)

Simard, R.

1977-01-01

Although the standard gauge model of weak and electromagnetic interactions based on the work of Salam and Weinberg has met with great success, there are experimental facts that will require its extension or its modification to a new gauge model; the discovery of a heavy lepton at SLAC and the absence of parity violation in atoms that is expected from the neutral weak current coupling to electrons are discussed. Three tests are proposed that bear on these questions. First, heavy lepton production in e + e - annihilation when one of the incident beams is longitudinally polarized is considered and the purely leptonic decay of this heavy lepton is examined. An asymmetry in the inclusive angular distribution of one charged lepton (electron or muon) is important in determining the structure of weak interactions of the heavy lepton. In fact, this angular asymmetry easily distinguishes between the cases V - A and V + A for the heavy lepton current. Then, the decay channel L → ν/sub L/ + one hadron is considered (L = heavy lepton) under the same experimental set-up and the inclusive one-hadron angular distribution examined. Parity nonconservation in the decay of the heavy lepton causes a conspicuous forward-backward asymmetry in the cos theta distribution of the inclusive hadron spectrum near the high energy end that can be distinguished easily from other sources of asymmetry. It is easy then to discover the chirality (V - A or V + A) of the heavy lepton current. Finally a test is proposed which provides unambigous and clear evidence for parity violation in e + e - annihilation. It consists in measuring a possible left-right asymmetry of inclusive hadron production with highly transversely polarized e + e - incident beams. If observed, this asymmetry provides evidence of a parity violating neutral current coupling to electrons

Emission characteristics of 6.78-MHz radio-frequency glow discharge plasma in a pulsed mode

Science.gov (United States)

Zhang, Xinyue; Wagatsuma, Kazuaki

2017-07-01

This paper investigated Boltzmann plots for both atomic and ionic emission lines of iron in an argon glow discharge plasma driven by 6.78-MHz radio-frequency (RF) voltage in a pulsed operation, in order to discuss how the excitation/ionization process was affected by the pulsation. For this purpose, a pulse frequency as well as a duty ratio of the pulsed RF voltage was selected as the experimenter parameters. A Grimm-style radiation source was employed at a forward RF power of 70 W and at an argon pressures of 670 Pa. The Boltzmann plot for low-lying excited levels of iron atom was on a linear relationship, which was probably attributed to thermal collisions with ultimate electrons in the negative glow region; in this case, the excitation temperature was obtained in a narrow range of 3300-3400 K, which was hardly affected by the duty ratio as well as the pulse frequency of the pulsed RF glow discharge plasma. This observation suggested that the RF plasma could be supported by a self-stabilized negative glow region, where the kinetic energy distribution of the electrons would be changed to a lesser extent. Additional non-thermal excitation processes, such as a Penning-type collision and a charge-transfer collision, led to deviations (overpopulation) of particular energy levels of iron atom or iron ion from the normal Boltzmann distribution. However, their contributions to the overall excitation/ionization were not altered so greatly, when the pulse frequency or the duty ratio was varied in the pulsed RF glow discharge plasma.

Production of a Scalar Boson and a Fermion Pair in Arbitrarily Polarized e - e + Beams

Science.gov (United States)

Abdullayev, S. K.; Gojayev, M. Sh.; Nasibova, N. A.

2018-05-01

Within the framework of the Standard Model (Minimal Supersymmetric Standard Model) we consider the production of the scalar boson HSM (h; H) and a fermion pair ff- in arbitrarily polarized, counterpropagating electron-positron beams e - e + ⇒ HSM (h; H) ff-. Characteristic features of the behavior of the cross sections and polarization characteristics (right-left spin asymmetry, degree of longitudinal polarization of the fermion, and transverse spin asymmetry) are investigated and elucidated as functions of the energy of the electron-positron beams and the mass of the scalar boson.

Setting-up of the Laser Induced Fluorescence diagnostic. Measurements of Cr density in a neon glow discharge; Puesta a punto del diagnstico de fluorescencia inducida por laser. Medidas de densidad de Cr en Glow discharg de Neon

Energy Technology Data Exchange (ETDEWEB)

Tafalla, D.; Cal, E. de la; Tabares, F. L.

1994-07-01

A plasma diagnostic based on the Laser Induced Fluorescence (LIF) technique has been set up in the Fusion Division at the CIEMAT. In a preliminary experiment, the density of sputtered chromium atoms produced in a neon glow discharge was measured. Firstly, the laser beam was characterized by calibration of its wavelength, bandwidth and energy profile and Rayleigh scattering in N2 was used for the optical system calibration. An absolute density of Cr atoms of n {approx} 5x10 cm was obtained in discharges at 100 mA and pressure of 15 mTorr and a linear dependence of the LIF signal us. current was found. These values are in agreement with those expected from the tabulated sputtering yields and the thermalization and diffusion of the sputtered atoms into the Ne plasma. (Author) 19 refs.

Synthesis of nanoparticles in an atmospheric pressure glow discharge

International Nuclear Information System (INIS)

Barankin, M.D.; Creyghton, Y.; Schmidt-Ott, A.

2006-01-01

Nanopowders are produced in a low temperature, non-equilibrium plasma jet (APPJ), which produces a glow discharge at atmospheric pressure, for the first time. Amorphous carbon and iron nanoparticles have been synthesized from Acetylene and Ferrocene/H 2 , respectively. High generation rates are achieved from the glow discharge at near-ambient temperature (40-80 deg. C), and rise with increasing plasma power and precursor concentration. Fairly narrow particle size distributions are measured with a differential mobility analyzer (DMA) and an aerosol electrometer (AEM), and are centered around 30-35 nm for carbon and 20-25 nm for iron. Particle characteristics analyzed by TEM and EDX reveal amorphous carbon and iron nanoparticles. The Fe particles are highly oxidized on exposure to air. Comparison of the mobility and micrograph diameters reveal that the particles are hardly agglomerated or unagglomerated. This is ascribed to the unipolar charge on particles in the plasma. The generated particle distributions are examined as a function of process parameters

The edge transient-current technique (E-TCT) with high energy hadron beam

Energy Technology Data Exchange (ETDEWEB)

Gorišek, Andrej; Cindro, Vladimir; Kramberger, Gregor; Mandić, Igor [J. Stefan Institute, Ljubljana (Slovenia); Mikuž, Marko [J. Stefan Institute, Ljubljana (Slovenia); University of Ljubljana (Slovenia); Muškinja, Miha; Zavrtanik, Marko [J. Stefan Institute, Ljubljana (Slovenia)

2016-09-21

We propose a novel way to investigate the properties of silicon and CVD diamond detectors for High Energy Physics experiments complementary to the already well-established E-TCT technique using laser beam. In the proposed setup the beam of high energy hadrons (MIPs) is used instead of laser beam. MIPs incident on the detector in the direction parallel to the readout electrode plane and perpendicular to the edge of the detector. Such experiment could prove very useful to study CVD diamond detectors that are almost inaccessible for the E-TCT measurements with laser due to large band-gap as well as to verify and complement the E-TCT measurements of silicon. The method proposed is being tested at CERN in a beam of 120 GeV hadrons using a reference telescope with track resolution at the DUT of few μm. The preliminary results of the measurements are presented.

Diagnosis and dynamics of low energy electron beams using DIADYN

International Nuclear Information System (INIS)

Marghitu, S.; Oproiu, C.; Toader, D.; Ruset, C.; Grigore, E.; Marghitu, O.; Vasiliu, M.

2008-01-01

The paper presents original results concerning electron beam diagnosis and dynamics using DIADYN, a low energy (10 - 50 kV), medium intensity (0.1 - 1 A) laboratory equipment. A key stage in the operation of DIADYN is the beam diagnosis, performed by the non-destructive, modified three-gradient method (MTGM). We concentrate on the better use of experimental and computational techniques, in order to improve the consistency of the results. At present, DIADYN is equipped with a hot filament vacuum electron source (VES), consisting of a convergent Pierce diode, working in a pulse mode. Since the plasma electron sources (PES) have a longer lifetime and produce higher beam currents, we discuss the possibility to replace the VES with a PES. Special attention is given to VES results in a functioning regime typical for a low energy glow discharge PES. (authors)

Diagnosis and dynamics of low energy electron beams using DIADYN

Energy Technology Data Exchange (ETDEWEB)

Marghitu, S [Electrostatica, ICPE-CA S.A., Spaiul Unirii 313, Sector 3, RO-74204 Bucharest (Romania); Oproiu, C; Toader, D; Ruset, C; Grigore, E [National Institute for Laser, Plasma and Radiation Physics, PO Box MG-36, 409 Atomistilor Street, RO-76900 Bucharest-Magurele (Romania); Marghitu, O [Institute for Space Sciences, INCDLPFR, PO Box MG-23, RO-76911 Bucharest-Magurele (Romania); Vasiliu, M [Politehnica University, 313 Splaiul Independentei, RO-060032, Bucharest (Romania)

2008-07-01

The paper presents original results concerning electron beam diagnosis and dynamics using DIADYN, a low energy (10 - 50 kV), medium intensity (0.1 - 1 A) laboratory equipment. A key stage in the operation of DIADYN is the beam diagnosis, performed by the non-destructive, modified three-gradient method (MTGM). We concentrate on the better use of experimental and computational techniques, in order to improve the consistency of the results. At present, DIADYN is equipped with a hot filament vacuum electron source (VES), consisting of a convergent Pierce diode, working in a pulse mode. Since the plasma electron sources (PES) have a longer lifetime and produce higher beam currents, we discuss the possibility to replace the VES with a PES. Special attention is given to VES results in a functioning regime typical for a low energy glow discharge PES. (authors)

Analysis of glow curves of TL readouts of CaSO4:Dy teflon based TLD badge in semiautomatic TLD badge reader

International Nuclear Information System (INIS)

Pradhan, S.M.; Sneha, C.; Adtani, M.M.

2010-01-01

The facility of glow curve storage and recall provided in the reader software is helpful for manual screening of the glow curves; however no further analysis is possible due to absence of numerical TL data at the sampling intervals. In the present study glow curves are digitized by modifying the reader software and then normalized to make them independent of the dose. The normalized glow curves are then analyzed by dividing them into five equal parts on time scale. This method of analysis is used to correlate the variation of total TL counts of the three discs with time elapsed post irradiation

Comprehensive Evaluation of the Properties of Nanocrystalline Diamond Coatings Grown Using CVD with E/H Field Glow Discharge Stabilization

Directory of Open Access Journals (Sweden)

Iu. Nasieka

2015-01-01

Full Text Available The nanocrystalline diamond films (coatings were prepared using the plasma enhanced chemical vapor deposition (PECVD technique. In this method, direct current (DC glow discharge in the crossed E/H fields was used to activate the gas phase. The diamond coatings were deposited from the working gas mixture CH4/H2 with addition of nitrogen in various concentrations. It was ascertained that addition of N2 to the working gas mixture leads to reduction in the sizes of diamond grains as well as to the substantial decrease in the resistivity of the studied films. The electrophysical data are in good agreement with the changes induced by varying the N2 content in the Raman scattering spectra. The increase in the N2 concentration causes significant lowering of the crystalline diamond related peak and increase in the intensity of the peaks related to the sp2-bonded carbon. These changes in the spectra indicate significant disordering of the structure of prepared films and its uniformity in the nanodiamond film volume. With the great possibility, it is associated with a decrease in the sizes of diamond crystalline grains and tendency of NCD film to amorphization.

Compression of pulsed electron beams for material tests

Science.gov (United States)

Metel, Alexander S.

2018-03-01

In order to strengthen the surface of machine parts and investigate behavior of their materials exposed to highly dense energy fluxes an electron gun has been developed, which produces the pulsed beams of electrons with the energy up to 300 keV and the current up to 250 A at the pulse width of 100-200 µs. Electrons are extracted into the accelerating gap from the hollow cathode glow discharge plasma through a flat or a spherical grid. The flat grid produces 16-cm-diameter beams with the density of transported per one pulse energy not exceeding 15 J·cm-2, which is not enough even for the surface hardening. The spherical grid enables compression of the beams and regulation of the energy density from 15 J·cm-2 up to 15 kJ·cm-2, thus allowing hardening, pulsed melting of the machine part surface with the further high-speed recrystallization as well as an explosive ablation of the surface layer.

On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime

International Nuclear Information System (INIS)

Prevosto, L.; Mancinelli, B.; Chamorro, J. C.; Cejas, E.; Kelly, H.

2015-01-01

Low-frequency (100 Hz), intermediate-current (50 to 200 mA) glow discharges were experimentally investigated in atmospheric pressure air between blunt copper electrodes. Voltage–current characteristics and images of the discharge for different inter-electrode distances are reported. A cathode-fall voltage close to 360 V and a current density at the cathode surface of about 11 A/cm 2 , both independent of the discharge current, were found. The visible emissive structure of the discharge resembles to that of a typical low-pressure glow, thus suggesting a glow-like electric field distribution in the discharge. A kinetic model for the discharge ionization processes is also presented with the aim of identifying the main physical processes ruling the discharge behavior. The numerical results indicate the presence of a non-equilibrium plasma with rather high gas temperature (above 4000 K) leading to the production of components such as NO, O, and N which are usually absent in low-current glows. Hence, the ionization by electron-impact is replaced by associative ionization, which is independent of the reduced electric field. This leads to a negative current-voltage characteristic curve, in spite of the glow-like features of the discharge. On the other hand, several estimations show that the discharge seems to be stabilized by heat conduction; being thermally stable due to its reduced size. All the quoted results indicate that although this discharge regime might be considered to be close to an arc, it is still a glow discharge as demonstrated by its overall properties, supported also by the presence of thermal non-equilibrium

Electrostatic analyzer for electron and ion energy in glow discharge tube

International Nuclear Information System (INIS)

Bong Kil Yeon.

1984-01-01

The project, the construction and use of an electrostatic energy analyser (Faraday Cup) are described explaining physically its working mechanism. The analyser was used in a glow discharge tube with air and an air-argon mixture. A chapter with the theory of the glow discharge is included. The ion and electron temperatures, the plasma potential and the distribution function for ions and electrons were measured. The electron temperature and plasma potential were also measured using a Langmuir probe and the results show reasonable agreement with the results of the analyser. Good fits of the experimental electron and ion distribution functions were obtained with Maxwellian distributions centered values near the plasma potential. Finally, we discuss the performance of the analyser compared to Langmuir probes. (author) [pt

Beam-Beam Effects

International Nuclear Information System (INIS)

Herr, W; Pieloni, T

2014-01-01

One of the most severe limitations in high-intensity particle colliders is the beam-beam interaction, i.e. the perturbation of the beams as they cross the opposing beams. This introduction to beam-beam effects concentrates on a description of the phenomena that are present in modern colliding beam facilities

E3 Success Story - Advancing Performance in Sustainability and Workforce Development

Science.gov (United States)

E3: North Carolina advances performance in sustainability and workforce development strategies for the state's manufacturers. The initiative helps communities and manufacturers address energy and sustainability challenges by leveraging expertise.

E-Beam Effects on CMOS Active Pixel Sensors

International Nuclear Information System (INIS)

Kang, Dong Ook; Jo, Gyu Seong; Kim, Hyeon Daek; Kim, Hyunk Taek; Kim, Jong Yeol; Kim, Chan Kyu

2011-01-01

Three different CMOS active pixel structures manufactured in a deep submicron process have been evaluated with electron beam. The devices were exposed to 1 MeV electron beam up to 5kGy. Dark current increased after E-beam irradiation differently at each pixel structure. Dark current change is dependent on CMOS pixel structures. CMOS image sensors are now good candidates in demanding applications such as medical image sensor, particle detection and space remote sensing. In these situations, CISs are exposed to high doses of radiation. In fact radiation is known to generate trapped charge in CMOS oxides. It can lead to threshold voltage shifts and current leakages in MOSFETs and dark current increase in photodiodes. We studied ionizing effects in three types of CMOS APSs fabricated by 0.25 CMOS process. The devices were irradiated by a Co 60 source up to 50kGy. All irradiation took place at room temperature. The dark current in the three different pixels exhibits increase with electron beam exposure. From the above figure, the change of dark current is dependent on the pixel structure. Double junction structure has shown relatively small increase of dark current after electron beam irradiation. The dark current in the three different pixels exhibits increase with electron beam exposure. The contribution of the total ionizing dose to the dark current increase is small here, since the devices were left unbiased during the electron beam irradiation. Radiation hardness in dependent on the pixel structures. Pixel2 is relatively vulnerable to radiation exposure. Pixel3 has radiation hardened structure

Time dependent argon glow discharge treatment of Al-alloy

Indian Academy of Sciences (India)

The energy dispersive microanalysis by X-rays (EDX) is used to determine ... surface preparation of vacum components and vacuum system of any size. ... In this work, samples of aluminium alloy are treated under dc glow discharge .... (ii) For ałuninium, iron and germanium, relative weight percentage decreases or in-.

CP-sensitive observables in chargino production with transverse e± beam polarization

International Nuclear Information System (INIS)

Bartl, A.; Hohenwarter-Sodek, K.; Kernreiter, T.; Rud, H.

2004-01-01

We consider the process e + e - →χ + i χ - j at a linear collider with transverse e ± beam polarization. We investigate the influence of the CP phases on azimuthal asymmetries in e + e - →χ + i χ - j with subsequent two-body decays χ - j →ν l l - and χ - j →W - χ 0 1 . We show that triple product correlations involving the transverse e ± beam polarization vanish if at least one subsequent chargino decay is not observed. We derive this result within the minimal supersymmetric standard model (MSSM) with complex parameters; however, it holds also in the general MSSM with SUSY flavor violation. (orig.)

Ultra-low-energy (<10 eV/u) ion beam bombardment effect on naked DNA

Energy Technology Data Exchange (ETDEWEB)

Thopan, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thongkumkoon, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand); Suwannakachorn, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@thep-center.org [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

2014-05-01

Highlights: • Decelerated ultra-low energy ion beam bombarded naked DNA. • DNA form change induced by ion bombardment was investigated. • N-ion bombardment at 32 eV induced DNA single and double strand breaks. • Ar-ion bombardment at a-few-hundreds eV induced DNA single strand break. - Abstract: Since ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range, it is very interesting to know effects from ultra-low-energy ion interaction with DNA for understanding ion-beam-induced genetic mutation. Tens-keV Ar- and N-ion beams were decelerated to ultra-low energy ranging from 20 to 100 eV, or only a few to 10 eV/u, to bombard naked plasmid DNA. The bombarded DNA was analyzed using gel electrophoresis for DNA form changes. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks after bombarded by tens-eV ion beam. N-ion beam was found more effective in inducing DNA change and mutation than Ar-ion beam. The study demonstrated that the ion bombardment with energy as low as several-tens eV was able to break DNA strands and thus potentially to cause genetic modification of biological cells. The experimental results were discussed in terms of direct atomic collision between the ions and DNA atoms.

Ultra-low-energy (<10 eV/u) ion beam bombardment effect on naked DNA

International Nuclear Information System (INIS)

Thopan, P.; Thongkumkoon, P.; Prakrajang, K.; Suwannakachorn, D.; Yu, L.D.

2014-01-01

Highlights: • Decelerated ultra-low energy ion beam bombarded naked DNA. • DNA form change induced by ion bombardment was investigated. • N-ion bombardment at 32 eV induced DNA single and double strand breaks. • Ar-ion bombardment at a-few-hundreds eV induced DNA single strand break. - Abstract: Since ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range, it is very interesting to know effects from ultra-low-energy ion interaction with DNA for understanding ion-beam-induced genetic mutation. Tens-keV Ar- and N-ion beams were decelerated to ultra-low energy ranging from 20 to 100 eV, or only a few to 10 eV/u, to bombard naked plasmid DNA. The bombarded DNA was analyzed using gel electrophoresis for DNA form changes. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks after bombarded by tens-eV ion beam. N-ion beam was found more effective in inducing DNA change and mutation than Ar-ion beam. The study demonstrated that the ion bombardment with energy as low as several-tens eV was able to break DNA strands and thus potentially to cause genetic modification of biological cells. The experimental results were discussed in terms of direct atomic collision between the ions and DNA atoms

Is this an arc or a glow discharge?

International Nuclear Information System (INIS)

Puchkarev, V.F.; Bochkarev, M.B.

1994-01-01

A well known criterion for distinguishing an arc discharge from a glow discharge is a low voltage drop (10--30 V) and a high current density that varies from a few tens to 10 6 A/cm 2 depending on arc type. The high current density is an attribute of arcs with cathode spots. The authors report here a study of the mechanism of emission in cathode spot arc where they realized a spotless discharge with a low voltage drop (30--50 V) and a high mean current density (10 4 --10 6 A/cm 2 ). The discharge was initiated between a broad cathode and point anode. The cathode was a smooth tungsten sphere electrode of about 100 μm in diameter. The point anode was made of various materials (Mo, Cu, Cd) with initial radius 1 μm. Before the experiment the cathode was cleaned by heating at 2,000 K at high vacuum (10 -8 Torr). The discharge was initiated by self-breakdown when electrodes under the voltage 200--500 V were brought to close proximity with each other. The cathode-anode spacing d at the moment of breakdown was estimated to be < 1 μm. The discharge current was varied within 1--3 A by changing the applied voltage and impedance of coaxial cable generator. The discharge burned during 100--1,000 ns. After the single discharge the cathode and anode were examined with a scanning electron microscope. The cathode surface exposed to the discharge was smooth, i.e. no erosion pits similar to arc craters were found on the cathode surface. The anode was shortened after discharge by 5--50 μm depending on current, material and cone angle. A high current density and low voltage drop implies that this is an arc discharge, while the cold cathode and the absence f cathode spot trace are pertinent to a dense glow discharge. The mechanism of emission involving secondary electron emission is to be discussed

Study on out-gassing by baking and glow discharge during wall conditioning of vacuum chamber

International Nuclear Information System (INIS)

Wang Zhiwen; Wei Weixing; Zhao Yuanqing; He Yanhe; Liao Yikui

2007-01-01

The model of out-gassing by baking and glow discharge cleaning (GDC) is set up. The properties of them are studied. Out-gassing by baking is from bulk and it obeys the diffusion equation. Out-gassing of glow discharge cleaning is mainly on surface, it is inducement out-gassing by sputtering. Thus the properties of out-gassing for baking and GDC on the HL-1M tokamak are analyzed. Some empirical formulas are given. (authors)

Monte Carlo dose calculation improvements for low energy electron beams using eMC

International Nuclear Information System (INIS)

Fix, Michael K; Frei, Daniel; Volken, Werner; Born, Ernst J; Manser, Peter; Neuenschwander, Hans

2010-01-01

The electron Monte Carlo (eMC) dose calculation algorithm in Eclipse (Varian Medical Systems) is based on the macro MC method and is able to predict dose distributions for high energy electron beams with high accuracy. However, there are limitations for low energy electron beams. This work aims to improve the accuracy of the dose calculation using eMC for 4 and 6 MeV electron beams of Varian linear accelerators. Improvements implemented into the eMC include (1) improved determination of the initial electron energy spectrum by increased resolution of mono-energetic depth dose curves used during beam configuration; (2) inclusion of all the scrapers of the applicator in the beam model; (3) reduction of the maximum size of the sphere to be selected within the macro MC transport when the energy of the incident electron is below certain thresholds. The impact of these changes in eMC is investigated by comparing calculated dose distributions for 4 and 6 MeV electron beams at source to surface distance (SSD) of 100 and 110 cm with applicators ranging from 6 x 6 to 25 x 25 cm 2 of a Varian Clinac 2300C/D with the corresponding measurements. Dose differences between calculated and measured absolute depth dose curves are reduced from 6% to less than 1.5% for both energies and all applicators considered at SSD of 100 cm. Using the original eMC implementation, absolute dose profiles at depths of 1 cm, d max and R50 in water lead to dose differences of up to 8% for applicators larger than 15 x 15 cm 2 at SSD 100 cm. Those differences are now reduced to less than 2% for all dose profiles investigated when the improved version of eMC is used. At SSD of 110 cm the dose difference for the original eMC version is even more pronounced and can be larger than 10%. Those differences are reduced to within 2% or 2 mm with the improved version of eMC. In this work several enhancements were made in the eMC algorithm leading to significant improvements in the accuracy of the dose calculation

Monte Carlo dose calculation improvements for low energy electron beams using eMC.

Science.gov (United States)

Fix, Michael K; Frei, Daniel; Volken, Werner; Neuenschwander, Hans; Born, Ernst J; Manser, Peter

2010-08-21

The electron Monte Carlo (eMC) dose calculation algorithm in Eclipse (Varian Medical Systems) is based on the macro MC method and is able to predict dose distributions for high energy electron beams with high accuracy. However, there are limitations for low energy electron beams. This work aims to improve the accuracy of the dose calculation using eMC for 4 and 6 MeV electron beams of Varian linear accelerators. Improvements implemented into the eMC include (1) improved determination of the initial electron energy spectrum by increased resolution of mono-energetic depth dose curves used during beam configuration; (2) inclusion of all the scrapers of the applicator in the beam model; (3) reduction of the maximum size of the sphere to be selected within the macro MC transport when the energy of the incident electron is below certain thresholds. The impact of these changes in eMC is investigated by comparing calculated dose distributions for 4 and 6 MeV electron beams at source to surface distance (SSD) of 100 and 110 cm with applicators ranging from 6 x 6 to 25 x 25 cm(2) of a Varian Clinac 2300C/D with the corresponding measurements. Dose differences between calculated and measured absolute depth dose curves are reduced from 6% to less than 1.5% for both energies and all applicators considered at SSD of 100 cm. Using the original eMC implementation, absolute dose profiles at depths of 1 cm, d(max) and R50 in water lead to dose differences of up to 8% for applicators larger than 15 x 15 cm(2) at SSD 100 cm. Those differences are now reduced to less than 2% for all dose profiles investigated when the improved version of eMC is used. At SSD of 110 cm the dose difference for the original eMC version is even more pronounced and can be larger than 10%. Those differences are reduced to within 2% or 2 mm with the improved version of eMC. In this work several enhancements were made in the eMC algorithm leading to significant improvements in the accuracy of the dose

Setting-up of the Laser Induced Fluorescence diagnostic. Measurements of Cr density in a neon glow discharge

International Nuclear Information System (INIS)

Tafalla, D.; Cal, E. de la; Tabares, F. L.

1994-01-01

A plasma diagnostic based on the Laser Induced Fluorescence (LIF) technique has been set up in the Fusion Division at the CIEMAT. In a preliminary experiment, the density of sputtered chromium atoms produced in a neon glow discharge was measured. Firstly, the laser beam was characterized by calibration of its wavelength, bandwidth and energy profile and Rayleigh scattering in N2 was used for the optical system calibration. An absolute density of Cr atoms of n ∼ 5x10 cm was obtained in discharges at 100 mA and pressure of 15 mTorr and a linear dependence of the LIF signal us. current was found. These values are in agreement with those expected from the tabulated sputtering yields and the thermalization and diffusion of the sputtered atoms into the Ne plasma. (Author) 19 refs

Measurements of current density distribution in shaped e-beam writers

Czech Academy of Sciences Publication Activity Database

Bok, Jan; Horáček, Miroslav; Kolařík, Vladimír; Urbánek, Michal; Matějka, Milan; Krzyžánek, Vladislav

2016-01-01

Roč. 149, JAN 5 (2016), s. 117-124 ISSN 0167-9317 R&D Projects: GA ČR(CZ) GA14-20012S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : shaped e-beam writer * electron beam * current density Subject RIV: JB - Sensors, Measurment, Regulation Impact factor: 1.806, year: 2016

Binary and ternary gas mixtures with temperature enhanced diffuse glow discharge characteristics for use in closing switches

Science.gov (United States)

Christophorou, L.G.; Hunter, S.R.

1990-06-26

An improvement to the gas mixture used in diffuse glow discharge closing switches is disclosed which includes binary and ternary gas mixtures which are formulated to exhibit decreasing electron attachment with increasing temperature. This increases the efficiency of the conductance of the glow discharge and further inhibits the formation of an arc. 11 figs.

Design and test of-80 kV snubber core assemblies for MFTF sustaining-neutral-beam power supplies

International Nuclear Information System (INIS)

Bishop, S.R.; Mayhall, D.J.; Wilson, J.H.; De Vore, K.R.; Ross, R.I.; Sears, R.G.

1981-01-01

Core snubbers, located near the neutral beam source ends of the Mirror Fusion Test Facility (MFTF) Sustaining Neutral Beam Power Supply System (SNBPSS) source cables, protect the neutral beam source extractor grid wires from overheating and sputtering during internal sparkdowns. The snubbers work by producing an induced counter-emf which limits the fault current and by absorbing the capacitive energy stored on the 80 kV source cables and power supplies. A computer program STACAL was used in snubber magnetic design to choose appropriate tape wound cores to provide 400 Ω resistance and 25 J energy absorption. The cores are mounted horizontally in a dielectric structure. The central source cable bundle passes through the snubber and terminates on three copper buses. Multilam receptacles on the buses connect to the source module jumper cables. Corona rings and shields limit electric field stresses to allow close clearances between snubbers

Radiofrequency glow discharge time of flight mass spectrometry: pulsed vs. continuous mode

International Nuclear Information System (INIS)

Lobo, L.; Pereiro, R.; Sanz-Medel, A.; Bordel, N.; Tempez, A.; Chapon, P.; Hohl, M.; Michler, J.

2009-01-01

Full text: Glow discharge (GD) is a well established tool for the direct analysis of solids. The application field of the original direct current GD, restricted to conductive samples, has been extended by radiofrequency powered GDs that can be applied for conductive and non-conductive samples. Moreover, the introduction of pulsed GD has opened the possibility of applying higher instantaneous powers that can improve the atomization-ionization processes and therefore the sensitivity. Furthermore, pulsed-GD may enable temporal separation of discharge gas species from the sample ions. In this work the analytical performances of radiofrequency and pulsed radiofrequency glow discharges are evaluated by using a time of flight mass analyzer (TOFMS). (author)

Does exclusion of protest zeros and warm-glow bidders cause selection bias in Contingent Valuation?

DEFF Research Database (Denmark)

Grammatikopoulou, Ioanna; Olsen, Søren Bøye; Pouta, Eija

A great issue of concern in valuation studies is whether respondents provide trustworthy and reliable answers conditional on the perceived information. Respondent may report either a higher than the true Willingness-To-Pay (WTP) due to warm glow or embedding effects or zero WTP which is lower than...... the true WTP due to protest behavior. We conduct a contingent valuation study to estimate the WTP for conserving a Natura 2000 wetland area in Greece. We find that 54% of the positive bidders exert warm glow motivations while 29% of all responses can be classified as protest zero bids. We employ three....... Our findings show that removal of warm glow positive bidders does not distort the WTP estimate in any significant way. However, using the same approach for protest zero bidders, we find strong evidence of selection bias associated with removal of protest zero responses. Specifically, WTP estimates...

Modeling electron beam parameters and plasma interface position in an anode plasma electron gun with hydrogen atmosphere

Science.gov (United States)

Krauze, A.; Virbulis, J.; Kravtsov, A.

2018-05-01

A beam glow discharge based electron gun can be applied as heater for silicon crystal growth systems in which silicon rods are pulled from melt. Impacts of high-energy charged particles cause wear and tear of the gun and generate an additional source of silicon contamination. A steady-state model for electron beam formation has been developed to model the electron gun and optimize its design. Description of the model and first simulation results are presented. It has been shown that the model can simulate dimensions of particle impact areas on the cathode and anode, but further improvements of the model are needed to correctly simulate electron trajectory distribution in the beam and the beam current dependence on the applied gas pressure.

Camp GLOW (Girls Leading Our World): Handbook for Volunteers.

Science.gov (United States)

Peace Corps, Washington, DC. Information Collection and Exchange Div.

Camp GLOW (Girls Leading Our World) began in Romania in 1995 as a weeklong leadership camp with the purpose of encouraging young women to become active citizens by building their self-esteem and confidence, increasing their self-awareness, and developing their skills in goal-setting, assertiveness, and career and life planning. Since that first…

Thermoluminescent properties of LiF:NaF multilayers thin films

International Nuclear Information System (INIS)

Mauricio, Claudia Lucia P.; Mauricio, Marcos H.P.; Nunes, Raul A.

1996-01-01

LiF and NaF and LiF:NaF multilayer films were grown by the assisted physical deposition method of beam evaporation. All films were grown by the assisted physical deposition method of e-beam evaporation. All films were made with a deposition rate of 10 A/s on aluminium and stainless steel substrates. Both substrates were kept at room temperature, 150 deg C and 300 deg C. The films were irradiated with 10 Gy in a 60 Co source. The thermoluminescence (TL) glow curves are similar for both substrates, with only a small dislocation in temperature of about 10 deg C. This dislocation in temperature are supposed to be related with its different thermal conductivity. The TL glow curves of films grown on aluminium substrates are more intense. TL of LiF films are similar of the TL of LiF crystals. The TL glow curves of multilayer LiF:NaF films can not be explained as a simple superposition of the glow curves of individual LiF and NaF layers. Thin layers of NaF seems not change very much the glow peaks structure of LiF films. (author)

Study on the E-beam pulse width scaling for a 25-kilojoule KrF amplifier

International Nuclear Information System (INIS)

Ramirez, J.J.

1983-02-01

The KrF laser is being considered as an ICF driver candidate. Since this laser is not an energy storing system, the output energy of an amplifier is delivered over the entire pulse width of the excitation source. E-beam pumping is preferred for large energy systems. The e-beam pulse width is constrained to a few hundred nanoseconds by laser operation and pulsed power considerations. The target requires pulses of a few nanoseconds. Angular multiplexing of probe beams through the amplifier is a preferred scheme for bridging this difference in timing requirements. Progressively shorter target irradiation times may be obtained by using shorter pulse probe beams and by either increasing the number of angular multiplexed beams or by decreasing the e-beam pulse width. This report documents results of a study on the consequences of following the latter approach

Spectroscopic Study of Electrical Glow Discharges in Gases

Science.gov (United States)

Reyes, P. G.; Evangelista, M.; Trujillo, C.; Castillo, F.; Rangel, J.

2006-12-01

The variation of the power of the light emitted in a Glow Discharge in Gases of low pressure (GDGLP) excited by a DC source was studied. A lack of dependency of the kind of gas used and the pressure it is located at was obtained. This is comparable to the potential drop which takes place in the discharge by inelastic collisions such as ionization, recombination, excitation, relaxation, etc.

MD421: Electron cloud studies on 25 ns beam variants (BCMS, 8b+4e)

CERN Document Server

Iadarola, Giovanni; Belli, Eleonora; Carver, Lee Robert; Dijkstal, Philipp; Li, Kevin Shing Bruce; Mether, Lotta; Romano, Annalisa; Rumolo, Giovanni; CERN. Geneva. ATS Department

2017-01-01

This note describes a Machine Development session performed with the main goal of studying the e-cloud mitigation that can be obtained by injecting mixed trains of 8b+4e beam type and trains having the standard 25 ns structure. Additionally, in the course of the MD, the pure 8b+4e beam was also checked to be stable when injected with low chromaticity and octupole current settings. Subsequently, the operational BCMS 25 ns beam was also injected with the 8b+4e settings and found to be unstable. The operational settings for injection were re-found by gradually increasing the chromaticity and octupole knobs until all the bunches of the injected beam could remain stable after injection.

Studies on the Electrical Characteristics of a DC Glow Discharge by Using Langmuir Probe

International Nuclear Information System (INIS)

Safaai, S. S.; Yap, S. L.; Wong, C. S.; Muniandy, S. V.; Smith, P. W.

2010-01-01

Electrical characteristics of a DC glow discharge are studied with the aim of determining the suitable parameters for stable operation of the dusty plasma system. The presence of dust particles in plasma significantly alters the charged particle equilibrium in the plasma and leads to various phenomena. Argon plasma produced by DC glow discharge is investigated with a further goal of studying dusty plasma phenomena. The discharge system has two disc-shaped parallel plate electrodes. The electrodes are enclosed in a large cylindrical stainless steel chamber filled with argon gas. Two important physical parameters affecting the condition of the discharge are the gas pressure and the inter-electrode distance. A single Langmuir probe based on the Keithley source meter is used to determine the electron temperature of the positive column. A custom designed probe is employed to determine the potential distribution between the electrodes during the discharge. The I-V characteristic curve and the Langmuir probe measurement are then used to determine the electron energy distribution of the glow discharge plasma.

Ion-beam doping of GaAs with low-energy (100 eV) C + using combined ion-beam and molecular-beam epitaxy

Science.gov (United States)

Iida, Tsutomu; Makita, Yunosuke; Kimura, Shinji; Winter, Stefan; Yamada, Akimasa; Fons, Paul; Uekusa, Shin-ichiro

1995-01-01

A combined ion-beam and molecular-beam-epitaxy (CIBMBE) system has been developed. This system consists of an ion implanter capable of producing ions in the energy range of 30 eV-30 keV and conventional solid-source MBE. As a successful application of CIBMBE, low-energy (100 eV) carbon ion (C+) irradiation during MBE growth of GaAs was carried out at substrate temperatures Tg between 500 and 590 °C. C+-doped layers were characterized by low-temperature (2 K) photoluminescence (PL), Raman scattering, and van der Pauw measurements. PL spectra of undoped GaAs grown by CIBMBE revealed that unintentional impurity incorporation into the epilayer is extremely small and precise doping effects are observable. CAs acceptor-related emissions such as ``g,'' [g-g], and [g-g]β are observed and their spectra are significantly changed with increasing C+ beam current density Ic. PL measurements showed that C atoms were efficiently incorporated during MBE growth by CIBMBE and were optically well activated as an acceptor in the as-grown condition even for Tg as low as 500 °C. Raman measurement showed negligible lattice damage of the epilayer bombarded with 100 eV C+ with no subsequent heat treatment. These results indicate that contamination- and damage-free impurity doping without postgrowth annealing can be achieved by the CIBMBE method.

Ion-beam doping of GaAs with low-energy (100 eV) C(+) using combined ion-beam and molecular-beam epitaxy

Science.gov (United States)

Lida, Tsutomu; Makita, Yunosuke; Kimura, Shinji; Winter, Stefan; Yamada, Akimasa; Fons, Paul; Uekusa, Shin-Ichiro

1995-01-01

A combined ion-beam and molecular-beam-epitaxy (CIBMBE) system has been developed. This system consists of an ion implanter capable of producing ions in the energy range of 30 eV - 30 keV and conventional solid-source MBE. As a successful application of CIBMBE, low-energy (100 eV) carbon ion (C(+)) irradiation during MBE growth of GaAs was carried out at substrate temperatures T(sub g) between 500 and 590 C. C(+)-doped layers were characterized by low-temperature (2 K) photoluminescence (PL), Raman scattering, and van der Pauw measurements. PL spectra of undoped GaAs grown by CIBMBE revealed that unintentional impurity incorporation into the epilayer is extremely small and precise doping effects are observable. C(sub As) acceptor-related emissions such as 'g', (g-g), and (g-g)(sub beta) are observed and their spectra are significantly changed with increasing C(+) beam current density I(sub c). PL measurements showed that C atoms were efficiently incorporated during MBE growth by CIBMBE and were optically well activated as an acceptor in the as-grown condition even for T(sub g) as low as 500 C. Raman measurement showed negligible lattice damage of the epilayer bombarded with 100 eV C(+) with no subsequent heat treatment. These results indicate that contamination- and damage-free impurity doping without postgrowth annealing can be achieved by the CIBMBE method.

Pre-exponential factor in general order kinetics of thermoluminescence and its influence on glow curves

International Nuclear Information System (INIS)

Sunta, C.M.; Ayta, W.E.F.; Chen, R.; Watanabe, S.

1997-01-01

A model of thermoluminescence kinetics based on a physically meaningful approach shows that the glow curve shapes undergo systematic changes with the change of trap occupancy (dose). In terms of the general order kinetics model it means that the kinetic order changes with sample dose. In parallel to the kinetic order, the pre-exponential factor also changes. In contrast to these results the glow curves calculated from the general order kinetics model show that the peak shape remains nearly constant when the trap occupancy is changed. When appropriately defined, the pre-exponential factor also has a fixed value independent of trap occupancy. In these respects the general order kinetics model, though empirical, seems to describe the glow peak behaviour quite successfully. However, regarding the peak temperature the theoretical results both from the physical as well as the empirical model seem to diverge from the experimental observations when the experimentally determined kinetics is non-first order. (author)

Direct measurements of particle transport in dc glow discharge dusty plasmas

International Nuclear Information System (INIS)

Thomas, E. Jr.

2001-01-01

Many recent experiments in dc glow discharge plasmas have shown that clouds of dust particles can be suspended near the biased electrodes. Once formed, the dust clouds have well defined boundaries while particle motion within the clouds can be quite complex. Because the dust particles in the cloud can remain suspended in the plasma for tens of minutes, it implies that the particles have a low diffusive loss rate and follow closed trajectories within the cloud. In the experiments discussed in this paper, direct measurements of the dust particle velocities are made using particle image velocimetry (PIV) techniques. From the velocity measurements, a reconstruction of the three-dimensional transport of the dust particles is performed. A qualitative model is developed for the closed motion of the dust particles in a dc glow discharge dusty plasma. (orig.)

E-plane Beam Width Reconfigurable Dipole Antenna with Tunable Parasitic Strip

DEFF Research Database (Denmark)

Zhang, Jin; Zhang, Shuai; Pedersen, Gert F.

2018-01-01

A 3-dB E-plane beam width (EPBW) reconfig- urable dipole antenna is proposed in this paper. By introducing a tunable C-shape strip, the EPBW of the dipole antenna can switch in three different modes: narrow, middle and wide. Three pairs of PIN diodes are used for controlling. The beam width tuning...

Beams of fast neutral atoms and molecules in low-pressure gas-discharge plasma

Energy Technology Data Exchange (ETDEWEB)

Metel, A. S., E-mail: ametel@stankin.ru [Moscow State University of Technology ' Stankin,' (Russian Federation)

2012-03-15

Fast neutral atom and molecule beams have been studied, the beams being produced in a vacuum chamber at nitrogen, argon, or helium pressure of 0.1-10 Pa due to charge-exchange collisions of ions accelerated in the sheath between the glow discharge plasma and a negative grid immersed therein. From a flat grid, two broad beams of molecules with continuous distribution of their energy from zero up to e(U + U{sub c}) (where U is voltage between the grid and the vacuum chamber and U{sub c} is cathode fall of the discharge) are propagating in opposite directions. The beam propagating from the concave surface of a 0.2-m-diameter grid is focused within a 10-mm-diameter spot on the target surface. When a 0.2-m-diameter 0.2-m-high cylindrical grid covered by end disks and composed of parallel 1.5-mm-diameter knitting needles spaced by 4.5 mm is immersed in the plasma, the accelerated ions pass through the gaps between the needles, turn inside the grid into fast atoms or molecules, and escape from the grid through the gaps on its opposite side. The Doppler shift of spectral lines allows for measuring the fast atom energy, which corresponds to the potential difference between the plasma inside the chamber and the plasma produced as a result of charge-exchange collisions inside the cylindrical grid.

Analysis of nickel-base alloys by Grimm-type glow discharge emission and x-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Ferreira, N.P.; Strauss, J.A.; Van Maarseveen, I.; Ivanfy, A.B.

1985-01-01

Nickel-base alloys can be analysed as satisfactorily as steels by XRF as well as by the Grimm-type source, in spite of problems caused by element combinations, spectral line overlap and the influence of the structure and heat conduction properties on sputtering in the glow discharge source. This extended abstract briefly discusses the use of Grimm-type glow discharge emission and XRF as techniques for the analysis of nickel-base alloys

Image-projection ion-beam lithography

International Nuclear Information System (INIS)

Miller, P.A.

1989-01-01

Image-projection ion-beam lithography is an attractive alternative for submicron patterning because it may provide high throughput; it uses demagnification to gain advantages in reticle fabrication, inspection, and lifetime; and it enjoys the precise deposition characteristics of ions which cause essentially no collateral damage. This lithographic option involves extracting low-mass ions (e.g., He + ) from a plasma source, transmitting the ions at low voltage through a stencil reticle, and then accelerating and focusing the ions electrostatically onto a resist-coated wafer. While the advantages of this technology have been demonstrated experimentally by the work of IMS (Austria), many difficulties still impede extension of the technology to the high-volume production of microelectronic devices. We report a computational study of a lithography system designed to address problem areas in field size, telecentricity, and chromatic and geometric aberration. We present a novel ion-column-design approach and conceptual ion-source and column designs which address these issues. We find that image-projection ion-beam technology should in principle meet high-volume-production requirements. The technical success of our present relatively compact-column design requires that a glow-discharge-based ion source (or equivalent cold source) be developed and that moderate further improvement in geometric aberration levels be obtained. Our system requires that image predistortion be employed during reticle fabrication to overcome distortion due to residual image nonlinearity and space-charge forces. This constitutes a software data preparation step, as do correcting for distortions in electron lithography columns and performing proximity-effect corrections. Areas needing further fundamental work are identified

Molecular beam (1-50eV) production by duoplasmatron source

International Nuclear Information System (INIS)

Delmas, M.; Gautherin, G.; Lejeune, C.

1974-01-01

The duoplasmatron discharge is commonly used to produce intense ion beams. A theoretical model of this discharge has been previously developed. The analysis of charge exchange processes between ions and neutral within the discharge shows that the source is able to deliver intense neutral beams (10 16 part s -1 ), the energy being in the range 1-50 eV. The intensity and energy distribution may be controlled from the discharge parameter variations. An experimental device has been realized in order to separate the neutral beam and the flux of charged particles; these latter are injected axially in a toroidal magnetic field configuration [fr

Beam Extinction Monitoring in the Mu2e Experiment

Energy Technology Data Exchange (ETDEWEB)

Prebys, Eric [Fermilab; Bartoszek, Larry [Technicare; Gaponenko, Andrei [Fermilab; Kasper, Peter [Fermilab

2015-06-01

The Mu2e Experiment at Fermilab will search for the conversion of a muon to an electron in the field of an atomic nucleus with unprecedented sensitivity. The experiment requires a beam consisting of proton bunches approximately 200ns FW long, separated by 1.7 microseconds, with no out-of-time protons at the 10⁻¹⁰ fractional level. The verification of this level of extinction is very challenging. The proposed technique uses a special purpose spectrometer which will observe particles scattered from the production target of the experiment. The acceptance will be limited such that there will be no saturation effects from the in-time beam. The precise level and profile of the out-of-time beam can then be built up statistically, by integrating over many bunches.

Testing the nature of the electroweak breaking from polarized e+e- beams

International Nuclear Information System (INIS)

Narison, S.; Wallet, J.C.

1985-01-01

We present a quite general expression of the longitudinal Asub(parallel) and the transverse Asub(perpendicular to) asymmetries for the single and pair production of electroweak (pseudo) scalars (Higgs, π tilde, sigma tilde, ssub(μ) ...) from polarized e + e - colliding beams via annihilation mechanism. We suggest hat the measurements of Asub(parallel) and Asub(perpendicular to) can reveal the nature of such spinless bosons and, then, the nature of the electroweak breaking, if these spinless bosons are produced at LEP and SLC energies. (orig.)

Closed form analytic solutions describing glow discharge plasma

International Nuclear Information System (INIS)

Pai, S.T.; Guo, X.M.; Zhou, T.D.

1996-01-01

On the basis of an analytic model developed previously [S. T. Pai, J. Appl. Phys. 71, 5820 (1992)], an improved version of the model for the description of dc glow discharge plasma was successfully developed. A set of closed form solutions was obtained from the governing equations. The two-dimensional, analytic solutions are functional and completely satisfy the governing equations, the actual boundary conditions, and Maxwell equations. They can be readily used to carry out numerical calculations without the necessity of employing any assumed boundary conditions. Results obtained from the model reveal that as the discharge gap spacing or pressure increases the maximum value in the electron density distribution moves toward the cathode. At a sufficiently large value of gap spacing, the positive column phenomenon begins to appear in the discharge region. The model has the capability of treating the positive column and negative glow as a continuous system without the necessity of studying them separately. The model also predicts a sharp rise of the positive ion density near the cathode and field reversal in the anode region. Variation of the electrode radius produces little effect on the axial spatial distribution of physical quantities studied. copyright 1996 American Institute of Physics

Thermoluminescence glow curves of irradiated PMMA and low density polyethylene

International Nuclear Information System (INIS)

Matsuda, Koji; Nakase, Yoshiaki; Kumakiri, Yasuhito; Tsuji, Yoshio.

1985-03-01

Light emission from polymers is observed when polymers preirradiated with ionizing radiation at low temperature are heated gradually. The light emission is supposedly resulted from recombination of electrons with active centers produced in polymers or from some other processes involving charge transfer, but no definite explanation has been given at present on the thermoluminescent centers. This report describes our studies on the effects of impurities contained in polymers and pressure of ambient gases on the thermoluminescent glow curve of PMMA and low density polyethylene, which are often used for plastic film dosimeters. In the glow curve of PMMA, only one peak was observed at 110 K in an H 2 or He atmosphere at 760 Torr, but the intensity of the peak decreased with decreasing the H 2 or He gas pressure. At 10 -5 Torr H 2 or He atmosphere the peak disappered, and two sharp peaks appeared in the temperature range from 200 to 250 K. On the other hand, in the glow curve of low density polyethylene, three peaks were observed at 120 K, 180 K and 250 K in the presence of H 2 or He gas at 760 Torr. The effects of pressure of ambient gases and impurities in the polyethylene on these peaks indicate that the peak at 120 K is due to luminescent center produced on the surface or just below the surface of the matrix by collision of excited atoms or molecules of gases with polymer molecules, the peak at 120 K is originated from impurities in the matrix, and the peak at 250 0 K corresponds to luminescent center produced in polyethylene matrix. (author)

Discharge current characteristics as an 'electrical method' for glow discharge plasma diagnosis

International Nuclear Information System (INIS)

Toma, M.; Paraschivescu, Alina; Morminches, Anisoara

2001-01-01

In its simplest form, the glow discharge can be established by passing an electric current through gas between two electrodes. The gas and the electrodes are contained in an insulating envelope. In many technological applications, and not only, the plasma devices are often treated like a black box. There is a series of external parameters or control variables which can be adjusted to obtain a desired effect, namely, the operating voltage, gas pressure, gas nature, gas flow rate, magnetic field strength and magnetic field configuration, electric field geometry, interelectrode distance, and cathode characteristics. The discharge current can be controlled by each of the above control variables. The core idea of this work is the following: a lot of information about the phenomena from the discharge volume, at electrodes or at the discharge bounding wall surface, can be obtained knowing how the change of one of the control parameters influences the discharge current. The following regimes were analyzed: dark discharges (background ionization, saturation regime, Townsend regime, corona regime), glow discharge (the normal and abnormal discharge) and arc discharge (glow to arc transition, non-thermal arcs, thermal arcs). It was concluded that the nonlinearity in the shape of the discharge current characteristics as a function of an external control parameter, can be correlated with the elementary processes and the dynamics of different space charge structures generated in plasma devices. (authors)

Hydrogen ion species analysis and related neutral beam injection power assessment in the Heliotron E neutral beam injection system

International Nuclear Information System (INIS)

Sano, Fumimichi; Obiki, Tokuhiro; Sasaki, Akihiko; Iiyoshi, Atsuo; Uo, Koji

1982-01-01

The hydrogen ion species in a Heliotron E neutral beam injection system of maximum electric power 6.3 MW were analyzed in order to assess the neutral beam power injected into the torus. The masimum p roton ratio of the cylindrical bucket type ion source used was observed to be more than 90 percent assuming that the angular divergences for the respective species in the beam are the same. The experimental data are compared with calculations using a particle balance model. The analysis indicates that the net injection power reaches nearly 2.7 MW at the optimal conditions of the system considering the geometrical limitation of the neutral beam path. (author)

Suppressing Ghost Diffraction in E-Beam-Written Gratings

Science.gov (United States)

Wilson, Daniel; Backlund, Johan

2009-01-01

A modified scheme for electron-beam (E-beam) writing used in the fabrication of convex or concave diffraction gratings makes it possible to suppress the ghost diffraction heretofore exhibited by such gratings. Ghost diffraction is a spurious component of diffraction caused by a spurious component of grating periodicity as described below. The ghost diffraction orders appear between the main diffraction orders and are typically more intense than is the diffuse scattering from the grating. At such high intensity, ghost diffraction is the dominant source of degradation of grating performance. The pattern of a convex or concave grating is established by electron-beam writing in a resist material coating a substrate that has the desired convex or concave shape. Unfortunately, as a result of the characteristics of electrostatic deflectors used to control the electron beam, it is possible to expose only a small field - typically between 0.5 and 1.0 mm wide - at a given fixed position of the electron gun relative to the substrate. To make a grating larger than the field size, it is necessary to move the substrate to make it possible to write fields centered at different positions, so that the larger area is synthesized by "stitching" the exposed fields.

Auxiliary glow discharge in the trigger unit of a hollow-cathode thyratron

Energy Technology Data Exchange (ETDEWEB)

Korolev, Yu. D.; Landl, N. V., E-mail: landl@lnp.hcei.tsc.ru; Geyman, V. G.; Frants, O. B.; Shemyakin, I. A.; Nekhoroshev, V. O. [Russian Academy of Sciences, Institute of High-Current Electronics, Siberian Branch (Russian Federation)

2016-08-15

Results from studies of a low-current glow discharge with a hollow cathode are presented. A specific feature of the discharge conditions was that a highly emissive tablet containing cesium carbonate was placed in the cathode cavity. In the absence of a tablet, the discharge ignition voltage was typically ≥3.5 kV, while the burning voltage was in the range of 500–600 V. The use of the tablet made it possible to decrease the ignition voltage to 280 V and maintain the discharge burning voltage at a level of about 130 V. A model of the current sustainment in a hollow-cathode discharge is proposed. Instead of the conventional secondary emission yield, the model uses a generalized emission yield that takes into account not only ion bombardment of the cathode, but also the emission current from an external source. The model is used to interpret the observed current−voltage characteristics. The results of calculations agree well with the experimental data. It is shown that, in some discharge modes, the external emission current from the cathode can reach 25% of the total discharge current.

Evaluation of trapping parameters of thermally stimulated luminescence glow curves in Cu-doped Li2B4O7 phosphor

International Nuclear Information System (INIS)

Manam, J.; Sharma, S.K.

2005-01-01

Evaluation of trapping parameters, including order of kinetics, activation energy and frequency factor, is one of the most important aspect of studies in the field of thermally stimulated luminescence (TSL). A polycrystalline sample of Cu-doped Li 2 B 4 O 7 was prepared by the melting method. Formation of the doped compound was checked by use of Fourier-transform infrared (FTIR) spectroscopy. TSL studies of the Cu-doped lithium tetraborate sample shows three glow peaks, the maximum emission occurring, respectively, at a temperature of 175 deg. C, 290 deg. C and 350 deg. C, the intensity of the 175 deg. C-glow peak being the maximum. The trapping parameters associated with this prominent glow peak of Cu-doped lithium tetraborate are reported herein, using the isothermal luminescence decay and glow curve shape (Chen's) methods. Our results show very good agreement between the trapping parameters calculated by the two methods

Surface science analysis of GaAs photocathodes following sustained electron beam delivery

Directory of Open Access Journals (Sweden)

V. Shutthanandan

2012-06-01

Full Text Available Degradation of the photocathode materials employed in photoinjectors represents a challenge for sustained operation of nuclear physics accelerators and high power free electron lasers (FEL. Photocathode quantum efficiency degradation is due to residual gases in the electron source vacuum system being ionized and accelerated back to the photocathode. These investigations are a first attempt to characterize the nature of the photocathode degradation, and employ multiple surface and bulk analysis techniques to investigate damage mechanisms including sputtering of the Cs-oxidant surface monolayer, other surface chemistry effects, and ion implantation. Surface and bulk analysis studies were conducted on two GaAs photocathodes, which were removed from the JLab FEL DC photoemission gun after delivering electron beam, and two control samples. The analysis techniques include helium ion microscopy, Rutherford backscattering spectrometry (RBS, atomic force microscopy, and secondary ion mass spectrometry (SIMS. In addition, two high-polarization strained superlattice GaAs photocathode samples, one removed from the continuous electron beam accelerator facility (CEBAF photoinjector and one unused, were also analyzed using transmission electron microscopy (TEM and SIMS. It was found that heat cleaning the FEL GaAs wafer introduces surface roughness, which seems to be reduced by prolonged use. The bulk GaAs samples retained a fairly well organized crystalline structure after delivering beam but show evidence of Cs depletion on the surface. Within the precision of the SIMS and RBS measurements, the data showed no indication of hydrogen implantation or lattice damage from ion back bombardment in the bulk GaAs wafers. In contrast, SIMS and TEM measurements of the strained superlattice photocathode show clear crystal damage in the wafer from ion back bombardment.

Singlet oxygen in the low-temperature plasma of an electron-beam-sustained discharge

International Nuclear Information System (INIS)

Vagin, N. P.; Ionin, A. A.; Klimachev, Yu. M.; Kotkov, A. A.; Kochetov, I. V.; Napartovich, A. P.; Podmar'kov, Yu. P.; Rulev, O. A.; Seleznev, L. V.; Sinitsyn, D. V.; Frolov, M. P.; Yuryshev, N. N.

2006-01-01

Results are presented from experimental and theoretical studies of the production of singlet delta oxygen in a pulsed electron-beam-sustained discharge ignited in a large (∼18-1) volume at a total gas mixture pressure of up to 210 Torr. The measured yield of singlet oxygen reaches 10.5%. It is found that varying the reduced electric field from ∼2 to ∼11 kV/(cm atm) slightly affects singlet oxygen production. It is shown experimentally that an increase in the gas mixture pressure or the specific input energy reduces the duration of singlet oxygen luminescence. The calculated time evolution of the singlet oxygen concentration is compared with experimental results

BaSO4:Eu as an energy independent thermoluminescent radiation dosimeter for gamma rays and C6+ ion beam

Science.gov (United States)

Sharma, Kanika; Bahl, Shaila; Singh, Birendra; Kumar, Pratik; Lochab, S. P.; Pandey, Anant

2018-04-01

BaSO4:Eu nanophosphor is delicately optimized by varying the concentration of the impurity element and compared to the commercially available thermoluminescent dosimeter (TLD) LiF:Mg,Ti (TLD-100) and by extension also to CaSO4:Dy (TLD-900) so as to achieve its maximum thermoluminescence (TL) sensitivity. Further, the energy dependence property of this barite nanophosphor is also explored at length by exposing the phosphor with 1.25 MeV of Co-60, 0.662 MeV of Cs-137, 85 MeV and 65 MeV of Carbon ion beams. Various batches of the phosphor at hand (with impurity concentrations being 0.05, 0.10, 0.20, 0.50 and 1.00 mol%) are prepared by the chemical co-precipitation method out of which BaSO4:Eu with 0.20 mol% Eu exhibits the maximum TL sensitivity. Further, the optimized nanophosphor exhibits a whopping 28.52 times higher TL sensitivity than the commercially available TLD-100 and 1.426 times higher sensitivity than TLD-900, a noteworthy linear response curve for an exceptionally wide range of doses i.e. 10 Gy to 2 kGy and a simple glow curve structure. Furthermore, when the newly optimized nanophosphor is exposed with two different energies of gamma radiations, namely 1.25 MeV of Co-60 (dose range- 10-300 Gy) and 0.662 MeV of Cs-137 (dose range- 1-300 Gy), it is observed that the shape and structure of the glow curves remain remarkably similar for different energies of radiation while the TL response curve shows little to no variation. When exposed to different energies of carbon ion beam BaSO4:Eu displays energy independence at lower doses i.e. from 6.059 to 14.497 kGy. Finally, even though energy independence is lost at higher doses, the material shows high sensitivity to higher energy (85 MeV) of carbon beam compared to the lower energy (65 MeV of C6+) and saturation is apparent only after 121.199 kGy. Therefore the present nanophosphor displays potential as an energy independent TLD.

Transitions between corona, glow, and spark regimes of nanosecond repetitively pulsed discharges in air at atmospheric pressure

OpenAIRE

Pai , David ,; Lacoste , Deanna ,; Laux , C.

2010-01-01

International audience; In atmospheric pressure air preheated from 300 to 1000 K, the nanosecond repetitively pulsed (NRP) method has been used to generate corona, glow, and spark discharges. Experiments have been performed to determine the parameter space (applied voltage, pulse repetition frequency, ambient gas temperature, and interelectrode gap distance) of each discharge regime. In particular, the experimental conditions necessary for the glow regime of NRP discharges have been determine...

Incorporating Sustainability into Engineering and Chemical Education Using E-Learning

Directory of Open Access Journals (Sweden)

Edmond Sanganyado

2018-03-01

Full Text Available The purpose of this study was to develop e-learning activities that could facilitate the integration of sustainability concepts and practices in engineering and chemical education. Using an online learning management system (LMS, undergraduate students in an applied chemistry program at a public university in Zimbabwe participated in an online discussion on the role of chemical reaction engineering in achieving environmental sustainability goals. In the second activity, the students were instructed to prepare a design report for a cost-effective and innovative wastewater treatment plant for a rural hospital. The design report was evaluated through peer review online. Quantitative and qualitative analyses were performed on the two online activities to evaluate student engagement, quality of responses and the incorporation of sustainability into their learning. In the online discussion, 97 comments were made averaging 120 words per comment. Furthermore, the students averaged 3.88 comments, with the majority of comments exhibiting simple and complex argumentation, a deep reflection and widespread use of terms associated with sustainability such as recycling, pollution, waste and the environment. Furthermore, the evaluation of peer reviews revealed that participants demonstrated they could identify the strengths and shortcomings in the design reports. Therefore, this study demonstrated that e-learning, particularly peer review and online discussion, could help chemistry and engineering students appreciate the need for chemical and engineering activities that encourage sustainable development.

Methane Conversion to C2 Hydrocarbons by Abnormal Glow Discharge at Atmospheric Pressure

International Nuclear Information System (INIS)

Dai Wei; Yu Hui; Chen Qi; Yin Yongxiang; Dai Xiaoyan

2005-01-01

Methane conversion to C 2 hydrocarbons has been investigated with the addition of hydrogen in a plasma reactor of abnormal glow discharge at atmospheric pressure. The aim of this experiment is to minimize coke formation and improve discharge stability. The typical conditions in the experiment are 300 ml of total feed flux and 400 W of discharge power. The experimental results show that methane conversion is from 91.6% to 35.2% in mol, acetylene selectivity is from 90.2% to 57.6%, and ethylene selectivity is approximately from 7.8% to 3.6%, where the coke increases gradually along with the increase of CH 4 /H 2 from 2: 8 to 9: 1. A stable discharge for a considerable running time can be obtained only at a lower ratio of CH 4 /H 2 2: 8 or 3: 7. These phenomena indicate that the coke deposition during methane conversion is obviously reduced by adding a large amount of hydrogen during an abnormal glow discharge. A qualitative interpretation is presented, namely, with abundant hydrogen, the possibility that hydrogen molecules are activated to hydrogen radicals is increased with the help of the abnormal glow discharge. These hydrogen radicals react with carbon radicals to form C 2 hydrocarbon products. Therefore, the deposition of coke is restrained

Characterization for Ceramic-coated magnets using E-beam and thermal annealing methods

International Nuclear Information System (INIS)

Kim, Hyug Jong; Kim, Hee Gyu; Kang, In Gu; Kim, Min Wan; Yang, Ki Ho; Lee, Byung Cheol; Choi, Byung Ho

2009-01-01

Hard magnet was usually used by coating SiO 2 ceramic thick films followed by the thermal annealing process. In this work, the alternative annealing process for NdFeB magnets using e-beam sources(1∼2 MeV, 50∼400 kGy) was investigated. NdFeB magnets was coated with ceramic thick films using the spray method. The optimal annealing parameter for e-beam source reveals to be 1 MeV and 300 kGy. The sample prepared at 1 MeV and 300 kGy was characterized by the analysis of the surface morphology, film hardness, adhesion and chemical stability. The mechanical property of thick film, especially film hardness, is better than that of thermal annealed samples at 180 .deg. C. As a result, e-beam annealing process will be one of candidate and attractive heat treatment process. In future, manufacturing process will be carried out in cooperation with the magnet company

Combined e-beam lithography using different energies

Czech Academy of Sciences Publication Activity Database

Krátký, Stanislav; Kolařík, Vladimír; Horáček, Miroslav; Meluzín, Petr; Král, Stanislav

2017-01-01

Roč. 177, JUN (2017), s. 30-34 ISSN 0167-9317 R&D Projects: GA TA ČR TE01020233; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : grayscale e-beam lithography * mix and match process * absorbed energy density * resist sensitivity * micro-optical elements Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Nano-processes (applications on nano-scale) Impact factor: 1.806, year: 2016

Diode laser excited optogalvanic spectroscopy of glow discharges

International Nuclear Information System (INIS)

Barshick, C. M.; Shaw, R. W.; Jennings, L. W.; Post-Zwicker, A.; Young, J. P.; Ramsey, J. M.

1997-01-01

The development of diode-laser-excited isotopically-selective optogalvanic spectroscopy (OGS) of uranium metal, oxide and fluoride in a glow discharge (GD) is presented. The technique is useful for determining 235 U/( 235 U+ 238 U) isotope ratios in these samples. The precision and accuracy of this determination is evaluated, and a study of experimental parameters pertaining to optimization of the measurement is discussed. Application of GD-OGS to other f-transition elements is also described

Diode laser excited optogalvanic spectroscopy of glow discharges

International Nuclear Information System (INIS)

Barshick, C.M.; Shaw, R.W.; Post-Zwicker, A., Young, J.P.; Ramsey, J.M.

1996-01-01

The development of diode-laser-excited isotopically-selective optogalvanic spectroscopy (OGS) of uranium metal, oxide and fluoride in a glow discharge (GD) is presented. The technique is useful for determining isotopic ratios of 235 U/( 235 U + 238 U) in the above samples. The precision and accuracy of this determination is evaluated, and a study of experimental parameters pertaining to optimization of he measurement is discussed. Application of the GD-OGS to other f-transition elements is also described

Glow discharge depth analysis of metallic elements in steels

International Nuclear Information System (INIS)

Berneron, R.

The glow discharge lamp designed by Grimm gives new possibilities in the optical spectrometry. The plasma produced is a cool emissive source and its advantages are the following: low spectral background, no reabsorption, linear calibration, very stable emission, very high yield. The sputtering produced by ionic bombardment of the sample enables the depth repartition of several elements to be made in the same run [fr

CRESCIMENTO ECONÔMICO E SUSTENTABILIDADE / Economic Growth and Sustainability

Directory of Open Access Journals (Sweden)

Gilberto Montibeller-Filho

2007-06-01

Full Text Available The subject “economic growth and sustainability” refers to the relationship between economicgrowth and its positive impact on the wellbeing of the population and on the environment. It is,therefore, about economic, as well as social and environmental, sustainability, i.e. the root ofthe sustainable development paradigm. A historical review is needed for understanding theroots of the emergence of this new socio-political and scientific paradigm. It starts from themoment when the economy was mainly viewed as an evil against the environment, to the pointwhen the new sustainable development, or eco-development, is developed. Then the paperpresents the present, and most important, ways that several public and private actions attemptto develop their economic activities guided by this paradigm, emphasising the Brazilian context.

V-I curves and plasma parameters in a high density DC glow discharge generated by a current-source

International Nuclear Information System (INIS)

Granda-Gutierrez, E E; Lopez-Callejas, R; Piedad-Beneitez, A de la; BenItez-Read, J S; Pacheco-Sotelo, J O; Pena-Eguiluz, R; A, R Valencia; Mercado-Cabrera, A; Barocio, S R

2008-01-01

Nitrogen DC glow discharges, conducted in a cylindrical geometry, have been characterized using a new current-source able to provide 10 -3 - 3 A for the sustainment of the discharge, instead of a conventional voltage-source. The V-I characteristic curves obtained from these discharges were found to fit the general form i(v) = A(p)v k(p) , whereby the plasma itself can be modeled as a voltage-controlled current-source. We conclude that the fitting parameters A and k, which mainly depend on the gas pressure p, are strongly related to the plasma characteristics, so much so that they can indicate the pressure interval in which the maximum plasma density is located, with values in the order of 10 16 m -3 at reduced discharge potential (300-600 V) and low working pressure (10 -1 - 10 1 Pa)

Thermoluminescence and glow curves analysis of γ-exposed Eu{sup 3+} doped K{sub 3}Y(PO{sub 4}){sub 2} nanophosphors

Energy Technology Data Exchange (ETDEWEB)

Gupta, Palvi; Bedyal, A.K. [School of Physics, Shri Mata Vaishno Devi University, Katra-182320, J& K (India); Kumar, Vinay, E-mail: vinaykdhiman@yahoo.com [School of Physics, Shri Mata Vaishno Devi University, Katra-182320, J& K (India); Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein 9300 (South Africa); Singh, Vivek K.; Khajuria, Y. [School of Physics, Shri Mata Vaishno Devi University, Katra-182320, J& K (India); Ntwaeaborwa, O.M.; Swart, H.C. [Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein 9300 (South Africa)

2016-01-15

Highlights: • First time, a detailed comparative study of the glow curves and kinetic parameters was made on K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor. • Combustion method was employed to synthesize the Eu{sup 3+} doped K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor. • The nanophosphor exhibited sublinear response suggesting that it is suitable for TL dosimetry. - Abstract: Eu{sup 3+} doped K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor was synthesized by combustion synthesis using urea as a fuel. The crystal structure and particle morphology of the nanophosphor were investigated by using X-ray diffraction and transmission electron microscopy, respectively. A Thermoluminescence (TL) study was carried out after exposing the samples to gamma radiation. The TL glow curves exhibited a prominent peak at 407 K and a small hump at 478 K. The intensity of the peaks increased with the increase in the dose of the gamma rays (0.01–5 kGy). The K{sub 3}Y(PO{sub 4}){sub 2}: Eu{sup 3+} (2.5 mol%) nanophosphor exhibited sublinear TL response to γ-radiation over a wide range of gamma doses (0.01–5 kGy). The TLanal program was used to analyze the glow curves of the K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor at different doses (0.2–5 kGy) and different heating rates (3–10 K/s). A comparative study was done for kinetic trapping parameters that were determined by the peak shape methods of Chen, Grossweiner and Lushchik. The frequency factors (s) for each glow peak were also calculated. The values of the activation energy (E) obtained by the TLanal program were in good agreement with those obtained by the peak shape methods. The effect of different amount of doses and different heating rates are discussed.

New developments in glow discharge optical emission and mass spectrometry

International Nuclear Information System (INIS)

Hoffmann, Volker; Dorka, Roland; Wilken, Ludger; Wetzig, Klaus

2000-01-01

This paper describes new developments in flow discharge optical emission (GD-OES) and mass spectrometry (GD-MS) at IFW and presents corresponding new applications (analysis of microelectronic multi-layer system by radio frequency glow discharge optical emission spectrometry (RF-GD-OES) and analysis of pure iron by a new Grimm-type GD-MS source)

Silicon solar cells made by ion implantation and glow discharge

International Nuclear Information System (INIS)

Ponpon, J.P.; Siffert, P.

1975-01-01

Three different methods of silicon solar cell preparation are considered and investigated: low energy implantation, glow discharge and prebombarded Schottky barriers. The properties of the contact layers realized by these processes are compared in terms of junction depth and sheet resistance. Preliminary results show the usefulness of these techniques for terrestrial solar cell realization [fr

Characterization of a 5-eV neutral atomic oxygen beam facility

Science.gov (United States)

Vaughn, J. A.; Linton, R. C.; Carruth, M. R., Jr.; Whitaker, A. F.; Cuthbertson, J. W.; Langer, W. D.; Motley, R. W.

1991-01-01

An experimental effort to characterize an existing 5-eV neutral atomic oxygen beam facility being developed at Princeton Plasma Physics Laboratory is described. This characterization effort includes atomic oxygen flux and flux distribution measurements using a catalytic probe, energy determination using a commercially designed quadrupole mass spectrometer (QMS), and the exposure of oxygen-sensitive materials in this beam facility. Also, comparisons were drawn between the reaction efficiencies of materials exposed in plasma ashers, and the reaction efficiencies previously estimated from space flight experiments. The results of this study show that the beam facility is capable of producing a directional beam of neutral atomic oxygen atoms with the needed flux and energy to simulate low Earth orbit (LEO) conditions for real time accelerated testing. The flux distribution in this facility is uniform to +/- 6 percent of the peak flux over a beam diameter of 6 cm.

An FFAG-ERL at Cornell University for eRHIC prototyping and bright-beam applications

Energy Technology Data Exchange (ETDEWEB)

Hoffstaetter, Georg [Cornell University, Ithaca, NY (United States)

2016-07-01

Cornell University has prototyped technology essential for any high-brightness electron ERL. This includes a DC gun and an SRF injector Linac with world-record current and normalized brightness in a bunch train, a high-current CW cryomodule for 70 MeV energy gain, a high-power beam stop, and several diagnostics tools for high-current and high-brightness beams, e.g. slid measurements for 6-D phase-space densities, a fast wire scanner for beam profiles, and beam loos diagnostics. All these are now available to equip a one-cryomodule ERL, and laboratory space has been cleared out and is radiation shielded to install this ERL at Cornell. BNL has designed a multi-turn ERL for eRHIC, where beam is transported more than 20 times around the RHIC tunnel. The number of transport lines is minimized by using two non-scaling (NS) FFAG arcs. A collaboration between BNL and Cornell has been formed to investigate the new NS-FFAG optics and the multi-turn eRHIC ERL design by building a 4-turn, one-cryomodule ERL at Cornell. It has a NS-FFAG return loop built with permanent magnets and is meant to accelerate 40 mA beam to 250 MeV.

Study of critical beta non-circular tokamak equilibria sustained in steady state by beam driven currents

International Nuclear Information System (INIS)

Okano, K.; Ogawa, Y.; Naitou, H.

1988-07-01

A new MHD-equilibrium/current-drive analysis code was developed to analyse the high beta tokamak equilibria consistent with the beam driven current profiles. In this new code, the critical beta equilibrium, which is stable against the ballooning mode, the kink mode and the Mercier mode, is determined first using MHD equilibrium and stability analysis codes (EQLAUS/ERATO). Then, the current drive parameters and the plasma parameters, required to sustain this critical beta equilibrium, are determined by iterative calculations. The beam driven current profiles are evaluated by the Fokker-Planck calculations on individual flux surfaces, where the toroidal effects on the beam ion and plasma electron trajectories are considered. The pressure calculation takes into account the beam ion and fast alpha components. A peculiarity of our new method is that the obtained solution is not only consistent with the MHD equilibrium but also consistent with the critical beta limit conditions, in the current profile and the pressure profile. Using this new method, β ∼ 21 % bean and β ∼ 6 % D-type critical beta equilibria were scanned for various parameters; the major radius, magnetic field, temperature, injection energy, etc. It was found that the achievable Q value for the bean type was always about 30 % larger than for the D-type cases, where Q = fusion power/beam power. With strong beanness, Q ∼ 6 for DEMO type tokamaks (∼500 MWth) and Q ∼ 20 for power reactor size (4.5 GWth) are achievable. On the other hand, the Q value would not exceed sixteen for the D-type machines. (author)

e-Biologics: Fabrication of Sustainable Electronics with "Green" Biological Materials.

Science.gov (United States)

Lovley, Derek R

2017-06-27

The growing ubiquity of electronic devices is increasingly consuming substantial energy and rare resources for materials fabrication, as well as creating expansive volumes of toxic waste. This is not sustainable. Electronic biological materials (e-biologics) that are produced with microbes, or designed with microbial components as the guide for synthesis, are a potential green solution. Some e-biologics can be fabricated from renewable feedstocks with relatively low energy inputs, often while avoiding the harsh chemicals used for synthesizing more traditional electronic materials. Several are completely free of toxic components, can be readily recycled, and offer unique features not found in traditional electronic materials in terms of size, performance, and opportunities for diverse functionalization. An appropriate investment in the concerted multidisciplinary collaborative research required to identify and characterize e-biologics and to engineer materials and devices based on e-biologics could be rewarded with a new "green age" of sustainable electronic materials and devices. Copyright © 2017 Lovley.

Quantum machine learning with glow for episodic tasks and decision games

Science.gov (United States)

Clausen, Jens; Briegel, Hans J.

2018-02-01

We consider a general class of models, where a reinforcement learning (RL) agent learns from cyclic interactions with an external environment via classical signals. Perceptual inputs are encoded as quantum states, which are subsequently transformed by a quantum channel representing the agent's memory, while the outcomes of measurements performed at the channel's output determine the agent's actions. The learning takes place via stepwise modifications of the channel properties. They are described by an update rule that is inspired by the projective simulation (PS) model and equipped with a glow mechanism that allows for a backpropagation of policy changes, analogous to the eligibility traces in RL and edge glow in PS. In this way, the model combines features of PS with the ability for generalization, offered by its physical embodiment as a quantum system. We apply the agent to various setups of an invasion game and a grid world, which serve as elementary model tasks allowing a direct comparison with a basic classical PS agent.

Influence of the circuit impedance on an electron beam controlled diffuse discharge with a negative differential conductivity

International Nuclear Information System (INIS)

Schaefer, G.; Schoenbach, K.H.; Kristiansen, M.; Strickland, B.E.; Korzekwa, R.A.; Hutcheson, G.Z.

1986-01-01

The use of attaching gases in an externally sustained diffuse discharge opening switch with a low attachment rate at low values of E/N and a high attachment rate at high values of E/N allows the discharge to operate with low losses in the closed switch phase and to achieve fast opening after the sustainment source is turned off. Such an attacher generates a J-E/N characteristic with a negative differential conductivity in an intermediate E/N range. Such a characteristic obstructs the closing process of the discharge if it is operated in a high impedance system. Experiments demonstrating these effects are presented for electron beam sustained discharges in mixtures of argon and C 2 F 6

SU-E-T-50: Automatic Validation of Megavoltage Beams Modeled for Clinical Use in Radiation Therapy

International Nuclear Information System (INIS)

Melchior, M; Salinas Aranda, F; Sciutto, S; Dodat, D; Larragueta, N

2014-01-01

Purpose: To automatically validate megavoltage beams modeled in XiO™ 4.50 (Elekta, Stockholm, Sweden) and Varian Eclipse™ Treatment Planning Systems (TPS) (Varian Associates, Palo Alto, CA, USA), reducing validation time before beam-on for clinical use. Methods: A software application that can automatically read and analyze DICOM RT Dose and W2CAD files was developed using MatLab integrated development environment.TPS calculated dose distributions, in DICOM RT Dose format, and dose values measured in different Varian Clinac beams, in W2CAD format, were compared. Experimental beam data used were those acquired for beam commissioning, collected on a water phantom with a 2D automatic beam scanning system.Two methods were chosen to evaluate dose distributions fitting: gamma analysis and point tests described in Appendix E of IAEA TECDOC-1583. Depth dose curves and beam profiles were evaluated for both open and wedged beams. Tolerance parameters chosen for gamma analysis are 3% and 3 mm dose and distance, respectively.Absolute dose was measured independently at points proposed in Appendix E of TECDOC-1583 to validate software results. Results: TPS calculated depth dose distributions agree with measured beam data under fixed precision values at all depths analyzed. Measured beam dose profiles match TPS calculated doses with high accuracy in both open and wedged beams. Depth and profile dose distributions fitting analysis show gamma values < 1. Relative errors at points proposed in Appendix E of TECDOC-1583 meet therein recommended tolerances.Independent absolute dose measurements at points proposed in Appendix E of TECDOC-1583 confirm software results. Conclusion: Automatic validation of megavoltage beams modeled for their use in the clinic was accomplished. The software tool developed proved efficient, giving users a convenient and reliable environment to decide whether to accept or not a beam model for clinical use. Validation time before beam-on for clinical use

Development of polarized e+ beams for future linear colliders

International Nuclear Information System (INIS)

Chiba, M.; Hamatsu, R.; Endo, A.

1995-01-01

We have so far been carrying out systematic investigations to create polarized e + on the basis of two new methods. One method is to use β + decay of radioactive nuclei with short life-time produced with a proton cyclotron and the other method is to use e + e - pair creation from polarized γ beams made through backward Compton scattering of laser lights. Here we describe technical details on productions of polarized e + and measurements of the polarization. The experiments of producing polarized e + will soon start. Although the e + intensity is not sufficiently high, we will acquire lots of know-how for further development of polarized e + sources with high quality which will possibly be applied to future linear colliders. (author)

Dosimetry of a prototype retractable eMLC for fixed-beam electron therapy

International Nuclear Information System (INIS)

Hogstrom, Kenneth R.; Boyd, Robert A.; Antolak, John A.; Svatos, Michelle M.; Faddegon, Bruce A.; Rosenman, Julian G.

2004-01-01

An electron multileaf collimator (eMLC) has been designed that is unique in that it retracts to 37 cm from the isocenter [63-cm source-to-collimator distance (SCD)] and can be deployed to distances of 20 and 10 cm from the isocenter (80 and 90 cm SCD, respectively). It is expected to be capable of arc therapy at 63 cm SCD; isocentric, fixed-beam therapy at 80 cm SCD; and source-to-surface distance (SSD), fixed-beam therapy at 90 cm SCD. In all positions, its leaves could be used for unmodulated or intensity-modulated therapy. Our goal in the present work is to describe the general characteristics of the eMLC and to demonstrate that its leakage characteristics and dosimetry are adequate for SSD, fixed-beam therapy as an alternative to Cerrobend cutouts with applicators once the prototype's leaves are motorized. Our eMLC data showed interleaf electron leakage at 15 MeV to be less than 0.1% based on a 0.0025 cm manufacturing tolerance, and lateral electron leakage at 5 and 15 MeV to be less than 2%. X-ray leakage through the leaves was 1.6% at 15 MeV. Our data showed that beam penumbra was independent of direction and leaf position. The dosimetric properties of square fields formed by the eMLC were very consistent with those formed by Cerrobend inserts in the 20x20 cm 2 applicator. Output factors exhibited similar field-size dependence. Airgap factors exhibited almost identical field-size dependence at two SSDs (105 and 110 cm), consistent with the common assumption that airgap factors are applicator independent. Percent depth-dose curves were similar, but showed variations up to 3% in the buildup region. The pencil-beam algorithm (PBA) fit measured data from the eMLC and applicator-cutout systems equally well, and the resulting two-dimensional (2-D) dose distributions, as predicted by the PBA, agreed well at common airgap distance. Simulating patient setups for breast and head and neck treatments showed that almost all fields could be treated using similar SSDs as

Glow plug ignitor tests in H2 mixtures

International Nuclear Information System (INIS)

Liparulo, N.J.; Olhoeft, J.E.; Paddleford, D.F.

1981-01-01

The AEP, TVA and DUKE Electric Power companies, in cooperation with Westinghouse Electric Corporation have defined a testing program to determine the effectiveness of a glow plug hydrogen ignition system. The ignitor's capability was demonstrated for both static and dynamic conditions. Tests were performed with both spray addition and fan induced turbulence. It ignited hydrogen for all tests performed. The results of tests did not differ significantly from similar tests data previously reported. This report presents a discussion of the test results

Diode laser excited optogalvanic spectroscopy of glow discharges

International Nuclear Information System (INIS)

Barshick, C.M.; Shaw, R.W.; Jennings, L.W.; Post-Zwicker, A.; Young, J.P.; Ramsey, J.M.

1997-01-01

The development of diode-laser-excited isotopically-selective optogalvanic spectroscopy (OGS) of uranium metal, oxide and fluoride in a glow discharge (GD) is presented. The technique is useful for determining 235 U/( 235 U+ 238 U) isotope ratios in these samples. The precision and accuracy of this determination is evaluated, and a study of experimental parameters pertaining to optimization of the measurement is discussed. Application of GD-OGS to other f-transition elements is also described. copyright 1997 American Institute of Physics

Tailoring the luminescence properties of Y_2O_3:Sm"3"+ nanophosphors by 6 MeV electron beam irradiation

International Nuclear Information System (INIS)

Sunitha, D.V.; Nagabhushana, H.; Hareesh, K.; Bhoraskar, V.N.; Dhole, S.D.

2017-01-01

Sm"3"+ (3 mol%) ions doped Y_2O_3 nanophosphors were synthesized by green synthesis route using Aloe Vera gel as fuel. The final product was irradiated by 6 MeV electron beam (E-beam) to different fluences in the range (2–10 × 10"1"3 e"− cm"−"2) and well characterized. Powder X-ray Diffractogram (PXRD) results revealed the loss of crystalline nature due to lattice disorder created during irradiation. Fourier Transform Infrared (FTIR) spectroscopic results showed absorption peaks around 688–843 cm"−"1 (Y-O bond), 1076 and 1398 cm"−"1 (C-O bond), 1505–1765 cm"−"1 and 3498 cm"−"1 (O-H bond). Scanning Electron Microscopic (SEM) images showed flake like morphological features. The Photoluminescence (PL) emission spectrum recorded at 407 nm excitation showed magnetic and electric dipole transitions at ∼569–575 ("4G_5_/_2 → "6H_5_/_2), ∼607–623 ("4G_5_/_2 → "6H_7_/_2) and ∼655–668 nm ("4G_5_/_2 → "6H_9_/_2) respectively. Thermoluminescence (TL) glow curve consists of three peaks in E-beam irradiated nanophosphors at 158, 243 and 352 °C due to creation of more number of trapping and luminescent centers. The E-beam irradiated Y_2O_3:Sm"3"+ nanophosphors showed strong PL emission with color co-ordinate values lying in the orange-red region. Therefore, this material can be potentially used as a red component in WLEDs (White LEDs). - Highlights: • Y_2O_3:Sm"3"+ nanophosphor was synthesized by solution combustion technique using Aloe Vera gel as a fuel. • Y_2O_3:Sm"3"+ nanophosphor was irradiated with 6 MeV E-beam in the fluence range 2–10 × 10"1"3e"− cm"−"2. • The size of the particle decreases and surface area increases with increase in E-beam fluence. • The E-beam irradiated Y_2O_3:Sm"3"+ nanophosphors PL intensity increases and CIE coordinate values moves towards red region indicating the potential usage of this phosphor for LED applications.

Dust acoustic waves in a dc glow-discharge plasma

International Nuclear Information System (INIS)

Molotkov, V.I.; Nefedov, A.P.; Torchinskii, V.M.; Fortov, V.E.; Khrapak, A.G.

1999-01-01

The spontaneous excitation of low-frequency oscillations of the macroparticle density in ordered dust structures levitating in standing striations of a dc glow discharge is discovered. It is concluded on the basis of a simplified linear model of an ideal collisionless plasma that the observed instability is caused by the drift motion of ions relative to the dust, which leads to the excitation of dust acoustic oscillations of the plasma

Influence of e-Beam Irradiation on the Performance of Energy Storage and Conversion Electrode

Energy Technology Data Exchange (ETDEWEB)

Baeok, Sung Hyeon; Jo, Won Jun; Lee, Duwon; Lee, Myung An [Inha Univ., Incheon (Korea, Republic of); Shin, Joong Hyeok; Lee, Byung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-07-01

Electron beam irradiation was known as an effective method to improve the stability and performance of electrodes by varying the chemical and physical properties. It has been reported that surface morphology, oxidation state, optical properties, and electrochemical properties can be modified by e-beam irradiation. In this work, influence of electron beam irradiation on the performance of electrode was studied for the applications in energy storage and conversion, such as secondary battery, supercapacitor, and fuel cell. Changes in physical and chemical properties of electrodes before and after e-beam irradiation were investigated. The crystallinity of the synthesized materials was investigated by X-ray diffraction, and the oxidation states were determined by X-ray photoelectron spectroscopy. Scanning electron microscopy was utilized to examine surface morphology. Crystallinity, surface morphology, and oxidation state were significantly changed by electron beam irradiation, and were found to be strongly dependent on irradiation time.

Acrylic acid grafted PDMS preliminary activated by Ar{sup +}beam plasma and cell observation

Energy Technology Data Exchange (ETDEWEB)

Kostadinova, A.; Zaekov, N. [Institute of Biophysics, BAS, Sofia (Bulgaria); Keranov, I. [Department of Polymer Engineering, University of Chemical Technology and Metallurgy (UCTM), Sofia (Bulgaria)

2007-07-01

Plasma based Ar{sup +} beam performed in RF (13.56 MHz) low-pressure (200 mTorr) glow discharge (at 100 W, 1200 W and 2500 W) with a serial capacitance was employed for surface modification of poly(dimethylsiloxane) (PDMS) aimed at improvement of its interactions with living cells. The presence of a serial capacitance ensures arise of an ion-flow inside the plasma volume directed toward the treated sample and the vary of the discharge power ensures varied density of the ion-flow The initial adhesion of human fibroblast cells was studied on the described above plasma based Ar{sup +}beam modified and acrylic acid (AA) grafted or not fibronectin (FN) pre-coated or ba resurfaces. The cell response seem sto be related with the peculiar structure and wettability of the modified PDMS surface layer after plasma based Ar{sup +} beam treatment followed or not by AA grafting. Key words: Biomaterials; Surface treatment of PDMS; Plasma based Ar{sup +} beam; Acrylic acid grafting; Fibroblast cells.

Pascal software structures achieve definite control of the 24 MFTF sustaining neutral-beam power supplies

International Nuclear Information System (INIS)

Anon.

1982-01-01

Precise control of large, complex systems is not assured unless there is known to be no unintended interactions in the control system. The software controlling the sustaining neutral-beam power supplies of the Mirror Fusion Test Facility accomplishes this feat. The software structures comprise some 16,000 lines of commented Pascal code, distributed amoung 10 different tasks. Each task may control any of the 24 power supplies. All the tasks are strictly event-driven, and are not subject to any system mode. Since there is no global information in the software, we know that all the power supplies are controlled independently

Unique heavy lepton signature at e+e- linear collider with polarized beams

International Nuclear Information System (INIS)

Moortgat-Pick, G.; Osland, P.; Pankov, A.A.; Tsytrinov, A.V.

2013-03-01

We explore the effects of neutrino and electron mixing with exotic heavy leptons in the process e + e - →W + W - within E 6 models. We examine the possibility of uniquely distinguishing and identifying such effects of heavy neutral lepton exchange from Z-Z' mixing within the same class of models and also from analogous ones due to competitor models with anomalous trilinear gauge couplings (AGC) that can lead to very similar experimental signatures at the e + e - International Linear Collider (ILC) for √(s)=350, 500 GeV and 1 TeV. Such clear identification of the model is possible by using a certain double polarization asymmetry. The availability of both beams being polarized plays a crucial role in identifying such exotic-lepton admixture. In addition, the sensitivity of the ILC for probing exotic-lepton admixture is substantially enhanced when the polarization of the produced W ± bosons is considered.

TL glow ratios at different temperature intervals of integration in thermoluminescence method. Comparison of Japanese standard (MHLW notified) method with CEN standard methods

International Nuclear Information System (INIS)

Todoriki, Setsuko; Saito, Kimie; Tsujimoto, Yuka

2008-01-01

The effect of the integration temperature intervals of TL intensities on the TL glow ratio was examined in comparison of the notified method of the Ministry of Health, Labour and Welfare (MHLW method) with EN1788. Two kinds of un-irradiated geological standard rock and three kinds of spices (black pepper, turmeric, and oregano) irradiated at 0.3 kGy or 1.0 kGy were subjected to TL analysis. Although the TL glow ratio exceeded 0.1 in the andesite according to the calculation of the MHLW notified method (integration interval; 70-490degC), the maximum of the first glow were observed at 300degC or more, attributed the influence of the natural radioactivity and distinguished from food irradiation. When the integration interval was set to 166-227degC according to EN1788, the TL glow ratios became remarkably smaller than 0.1, and the evaluation of the un-irradiated sample became more clear. For spices, the TL glow ratios by the MHLW notified method fell below 0.1 in un-irradiated samples and exceeded 0.1 in irradiated ones. Moreover, Glow1 maximum temperatures of the irradiated samples were observed at the range of 168-196degC, and those of un-irradiated samples were 258degC or more. Therefore, all samples were correctly judged by the criteria of the MHLW method. However, based on the temperature range of integration defined by EN1788, the TL glow ratio of un-irradiated samples remarkably became small compared with that of the MHLW method, and the discrimination of the irradiated sample from non-irradiation sample became clearer. (author)

Nonlinear time-series analysis of current signal in cathodic contact glow discharge electrolysis

International Nuclear Information System (INIS)

Allagui, Anis; Abdelkareem, Mohammad Ali; Rojas, Andrea Espinel; Bonny, Talal; Elwakil, Ahmed S.

2016-01-01

In the standard two-electrode configuration employed in electrolytic process, when the control dc voltage is brought to a critical value, the system undergoes a transition from conventional electrolysis to contact glow discharge electrolysis (CGDE), which has also been referred to as liquid-submerged micro-plasma, glow discharge plasma electrolysis, electrode effect, electrolytic plasma, etc. The light-emitting process is associated with the development of an irregular and erratic current time-series which has been arbitrarily labelled as “random,” and thus dissuaded further research in this direction. Here, we examine the current time-series signals measured in cathodic CGDE configuration in a concentrated KOH solution at different dc bias voltages greater than the critical voltage. We show that the signals are, in fact, not random according to the NIST SP. 800-22 test suite definition. We also demonstrate that post-processing low-pass filtered sequences requires less time than the native as-measured sequences, suggesting a superposition of low frequency chaotic fluctuations and high frequency behaviors (which may be produced by more than one possible source of entropy). Using an array of nonlinear time-series analyses for dynamical systems, i.e., the computation of largest Lyapunov exponents and correlation dimensions, and re-construction of phase portraits, we found that low-pass filtered datasets undergo a transition from quasi-periodic to chaotic to quasi-hyper-chaotic behavior, and back again to chaos when the voltage controlling-parameter is increased. The high frequency part of the signals is discussed in terms of highly nonlinear turbulent motion developed around the working electrode.

Study of the radiation effect on the mechanical properties of flammability and the glow wire of polyamide 6.6 with and without fiber glass reinforcement

International Nuclear Information System (INIS)

Ferro, Waldir Pedro; Silva, Leonardo Gondim de Andrade e

2002-01-01

The Automotive, Electric and Electronic Component Industry, more and more employ the Engineering Plastic as a viable alternative for the reduction of costs and increase of productivity without loss of quality. Polyamide 6.6 is an Engineering Plastic with distinguished role on this category of polymers due to its high thermal and chemical resistances and strength. The aim of this work is to present the results of Tensile Strength, Flexural Strength and Izod Notched Impact Strength as well as thermal experiments of Flammability (Automotive and Electronic Components Industry) and of Glow Wire (Electric Components Industry) of Polyamide 6.6 with or without Fiber Glass reinforcement, irradiated by Electron Beams in different doses. (author)

Sustainability of a Primary Care-Driven eConsult Service.

Science.gov (United States)

Liddy, Clare; Moroz, Isabella; Afkham, Amir; Keely, Erin

2018-03-01

Excessive wait times for specialist appointments pose a serious barrier to patient care. To improve access to specialist care and reduce wait times, we launched the Champlain BASE (Building Access to Specialists through eConsultation) eConsult service in April 2011. The objective of this study is to report on the impact of our multiple specialty eConsult service during the first 5 years of use after implementation, with a focus on growth and sustainability. We conducted a cross-sectional study of all eConsult cases submitted between April 1, 2011 and April 30, 2016, and measured impact with system utilization data and mandatory close-out surveys completed at the end of each eConsult. Impact indicators included time interval to obtain specialist advice, effect of specialist advice on the primary care clinician's course of action, and rate of avoidance of face-to-face visits. A total of 14,105 eConsult cases were directed to 56 different medical specialty groups, completed with a median response time of 21 hours, and 65% of all eConsults were resolved without a specialist visit. We observed rapid growth in the use of eConsult during the study period: 5 years after implementation the system was in use by 1,020 primary care clinicians, with more than 700 consultations taking place per month. This study presents the first in-depth look at the growth and sustainability of the multispecialty eConsult service. The results show the positive impact of an eConsult service and can inform other regions interested in implementing similar systems. © 2018 Annals of Family Medicine, Inc.

Velocity persistence of Brownian particles generated in a glow discharge

International Nuclear Information System (INIS)

Hurd, A.J.; Ho, P.

1989-01-01

Quasielastic light scattering from Brownian particles in the rarefied environment of a glow discharge exhibits Gaussianlike intensity correlation functions owing to the long mean free paths of the particles. The shape of the correlation function depends on the particles' average thermal velocity and friction coefficient, which can be related to aggregate mass and structure, and indicates a crossover from kinetic to hydrodynamic behavior

Investigation of plasma potential and pulsed discharge characteristics in enhanced glow discharge plasma immersion ion implantation and deposition

International Nuclear Information System (INIS)

Li Liuhe; Lu Qiuyuan; Fu, Ricky K.Y.; Chu, Paul K.

2009-01-01

Enhanced glow discharge plasma immersion ion implantation and deposition (EGD-PII and D) does not require external plasma sources. In this technique, the plasma is produced by self-glow discharge when a high negative voltage is applied to the sample. The small-area, pointed-shape hollow anode and large area tabular cathode form an electron-focused electric field. Using a special electric field design, the electrons from either the plasma or target (secondary electrons) are focused to a special hollow anode. As a result of the special electron-focusing field, the self-glow discharge process can be enhanced to achieve effective ion implantation into the substrate. In this work, the plasma potential distribution is investigated in details and the possible pulse discharge mechanism is discussed. The unique characteristics of the pulsed plasma and plasma extinction are studied.

Nature and mechanism of blue glow of corundum crystals; new point of view

International Nuclear Information System (INIS)

Bessonova, T.S.; Zabara, A.S.

1987-01-01

The photoluminescence and radioluminescence spectra were investigated for corrundum crystals grown by Verneil method with following thermal treatment in different conditions: 1) annealing in oxygen 8p=10 5 Pa, T=1770 K, t=5x10 5 s); 2) vacuum annealing (p=10 -3 Pa, T=2220 K, t=10 5 s); 3) annelaing in high reducing atmosphere. Two kinds of luminescence processes is shown to exist at 415-420 nm. Blue glow with δ ∼ 55 nm (band halfwidth) is due to anion vacancies while glow with δ ∼ 100 nm is caused by titanium ions of valancy 4. mechanisms of mentioned kinds of luminescence and their distinctive features presented. New model of electron transitions in Al 2 O 3 -lattice including anion vacancie for different excitation means is proposed

A comparison of hydrogen vs. helium glow discharge effects on fusion device first-wall conditioning

International Nuclear Information System (INIS)

Dylla, H.F.

1989-09-01

Hydrogen- and deuterium-fueled glow discharges are used for the initial conditioning of magnetic fusion device vacuum vessels following evacuation from atmospheric pressure. Hydrogenic glow discharge conditioning (GDC) significantly reduces the near-surface concentration of simple adsorbates, such as H 2 O, CO, and CH 4 , and lowers ion-induced desorption coefficients by typically three orders of magnitude. The time evolution of the residual gas production observed during hydrogen-glow discharge conditioning of the carbon first-wall structure of the TFTR device is similar to the time evolution observed during hydrogen GDC of the initial first-wall configuration in TFTR, which was primarily stainless steel. Recently, helium GDC has been investigated for several wall-conditioning tasks on a number of tokamaks including TFTR. Helium GDC shows negligible impurity removal with stainless steel walls. For impurity conditioning with carbon walls, helium GDC shows significant desorption of H 2 O, CO, and CO 2 ; however, the total desorption yield is limited to the monolayer range. In addition, helium GDC can be used to displace hydrogen isotopes from the near-surface region of carbon first-walls in order to lower hydrogenic retention and recycling. 38 refs., 6 figs

Development of chloride-induced corrosion in pre-cracked RC beams under sustained loading: Effect of load-induced cracks, concrete cover, and exposure conditions

Energy Technology Data Exchange (ETDEWEB)

Yu, Linwen [Université de Toulouse, UPS, INSA, LMDC, Toulouse (France); Université de Sherbrooke, Quebec (Canada); François, Raoul, E-mail: raoul.francois@insa-toulouse.fr [Université de Toulouse, UPS, INSA, LMDC, Toulouse (France); Dang, Vu Hiep [Hanoi Architectural University, Faculty of Civil Engineering, Hanoi (Viet Nam); L' Hostis, Valérie [CEA Saclay, CEA, DEN, DPC, SECR, Laboratoire d' Etude du Comportement des Bétons et des Argiles, Gif-sur-Yvette (France); Gagné, Richard [Université de Sherbrooke, Quebec (Canada)

2015-01-15

This paper deals with corrosion initiation and propagation in pre-cracked reinforced concrete beams under sustained loading during exposure to a chloride environment. Specimen beams that were cast in 2010 were compared to specimens cast in 1984. The only differences between the two sets of beams were the casting direction in relation to tensile reinforcement and the exposure conditions in the salt-fog chamber. The cracking maps, corrosion maps, chloride profiles, and cross-sectional loss of one group of two beams cast in 2010 were studied and their calculated corrosion rates were compared to that of beams cast in 1984 in order to investigate the factors influencing the natural corrosion process. Experimental results show that, after rapid initiation of corrosion at the crack tip, the corrosion process practically halted and the time elapsing before corrosion resumed depended on the exposure conditions and cover depth.

Investigation of the characteristics of thermoluminescence glow curves of natural hydrothermal quartz from Hakkari area in Turkey

International Nuclear Information System (INIS)

Topaksu, M.; Yüksel, M.; Dogan, T.; Nur, N.; Akkaya, R.; Yegingil, Z.; Topak, Y.

2013-01-01

In this study the dosimetric characteristics of some natural hydrothermal quartz (NHQ) samples collected from Hakkari were investigated by using the thermoluminescence (TL) technique for the purpose of determining whether they are suitable as dosimetric materials or not and calculating the kinetic parameters. The experiments carried out can be outlined as: analyzing TL glow curves of NHQ; determining the annealing conditions; the effects of pre-irradiation annealing procedures on TL sensitivity; the investigation of the characteristics of TL glow curves obtained after annealing the samples; determination of the trap parameters with the computerized glow curve deconvolution (CGCD) method and the peak shape (PS) method. The obtained results showed that the trap depths and the frequency factor values are consistent with the literature. The studied samples have linear dose responses for the absorbed doses ranging between ∼6.689 Gy and ∼301 Gy. In conclusion, the examined quartz samples can be used as dosimetric materials in high dose applications

Dynamic Mechanical Analysis of E-Beam and Thermally Curable IPN Thermosets

National Research Council Canada - National Science Library

Jensen, Robert

2002-01-01

.... E-beam curing of composites and adhesives offers advantages, such as reduced cure shrinkages, over traditional autoclave processing by curing multiple resins through the thickness for thick-section...

Surface analysis of uranyl fluoride layers with a glow discharge lamp

International Nuclear Information System (INIS)

Nel, J.T.; Stander, C.M.; Boehmer, R.G.

1991-01-01

Surface analysis with a Grimm-type glow discharge lamp was used to analyse uranyl fluoride layers that had formed on a nickel substrate after exposure to UF 6 . Narrow-band optical filters were used to isolate the intensities of three fluorine emission lines. An in-depth profile of layer composition was obtained. (author)

Research on the Plasma Anemometer Based on AC Glow Discharge

Directory of Open Access Journals (Sweden)

Bing Yu

2017-01-01

Full Text Available A new plasma anemometer based on AC glow discharge is designed in this article. Firstly, theoretical analysis of plasma anemometer working principle is introduced to prove the feasibility of the experimental measurement method. Then the experiments are carried out to study the effects of different parameters on the static discharge characteristics of the plasma anemometer system, by which the system optimization methods are obtained. Finally, several groups of appropriate parameters are selected to build the plasma anemometer system based on resistance capacitance coupling negative feedback AC glow discharge, and different airflow speeds are applied to obtain the achievable velocity measurement range. The results show that there is a linear relationship between airflow velocity and discharge current in an allowable error range, which can be applied for airflow velocity measurement. Negative feedback coupling module, which is composed of the coupling resistance and the coupling capacitance, has good effects on improving the system stability. The measurement range of the airflow velocity is significantly increased when the electrode gap is 3 mm, coupling resistance is 470 Ω, and coupling capacitance is 220 pF.

Sustained diffusive alternating current gliding arc discharge in atmospheric pressure air

DEFF Research Database (Denmark)

Zhu, Jiajian; Gao, Jinlong; Li, Zhongshan

2014-01-01

Rapid transition from glow discharge to thermal arc has been a common problem in generating stable high-power non-thermal plasmas especially at ambient conditions. A sustained diffusive gliding arc discharge was generated in a large volume in atmospheric pressure air, driven by an alternating...... current (AC) power source. The plasma column extended beyond the water-cooled stainless steel electrodes and was stabilized by matching the flow speed of the turbulent air jet with the rated output power. Comprehensive investigations were performed using high-speed movies measured over the plasma column...

E-beam direct write versus reticle/stepper technology for ASICS in small volume production

International Nuclear Information System (INIS)

Wheeler, M.J.

1987-01-01

The pros and cons of using e-beam direct writing or reticles plus optical/UV steppers in fast prototyping and the small volume production of ASICs are discussed. The main conclusion is that fast prototyping is best achieved by e-beam direct write whereas small volume production of ASICs is best done via reticles and optical/UV stepping provided that the reticles are made in-house rather than by commercial maskhouses

Study on application of the physical detection methods for electron beam-irradiated agricultural products

International Nuclear Information System (INIS)

Kim, Dong Yong; Park, Yong Dae; Jin, Chang Hyun; Choi, Dae Seong; Jeong, Il Yun; Yook, Hong Sun

2010-01-01

Physical detection methods, photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) were applied to detect electron beam-irradiated agricultural products, such as red pepper, black pepper, raisin, walnut, beef seasoning and pistachio. The absorbed irradiation doses for representative samples were controlled at 0, 1, 3, 5 and 10 kGy. PSL values for non-irradiated samples were 1 ) except beef seasoning, whereas those of irradiated samples were more than 5,000 photon counts, upper threshold (T 2 ) in black pepper, raisin, and beef seasoning and intermediates values of T 1 -T 2 in red pepper, walnut, and pistachio. Minerals separated from the samples for TL measurement showed that non-irradiated samples except pistachio (TL ratio, 0.12) were characterized by no glow curves situated at temperature range of 50 ∼ 400 .deg. C with TL ratio (0.01 ∼ 0.08), while irradiated samples except pistachio at only 1 kGy (TL ratio, 0.08) indicated glow curve at about 150 ∼ 250 .deg. C with TL ratio (0.28 ∼ 3.10). ESR measurements of irradiated samples any specific signals to irradiation. The samples of both red pepper ad pistachio were produced specific signals derived from cellulose radicals as well as single line signals for black pepper and walnut, and multiple signals derived from crystalline sugar radicals for raisin and beef seasoning. In conclusion, The ESR methods can apply for detection of pistachio exposed to electron beam but PSL and TL are not suitable methods. Furthermore, TL and ESR suggested that both techniques were more useful detection method than PSL to confirm whether red pepper, walnut and beef seasoning samples have been exposed to electron beam

Modeling Laser and e-Beam Generated Plasma-Plume Experiments Using LASNEX

CERN Document Server

Ho, D

1999-01-01

The hydrodynamics code LASNEX is used to model the laser and e-beam generated plasma-plume experiments. The laser used has a wavelength of 1 (micro)m and the FWHM spot size is 1 mm. The total laser energy is 160 mJ. The simulation shows that the plume expands at a velocity of about 6 cm/(micro)s. The e-beam generated from the Experimental Test Accelerator (ETA) has 5.5 MeV and FWHM spot size ranges from 2 to 3.3 mm. From the simulations, the plasma plume expansion velocity ranges from about 3 to 6 mm/(micro)s and the velocity increases with decreasing spot size. All the simulation results reported here are in close agreement with experimental data.

Proposed method to produce a highly polarized e+ beam for future linear colliders

International Nuclear Information System (INIS)

Okugi, Toshiyuki; Chiba, Masami; Kurihara, Yoshimasa

1996-01-01

We propose a method to produce a spin-polarized e + beam using e + e - pair-creation by circularly polarized photons. Assuming Compton scattering of an unpolarized e - beam and circularly polarized laser light, scattered γ-rays at the high end of the energy spectrum are also circularly polarized. If those γ-rays are utilized to create e ± pairs on a thin target, the spin-polarization is preserved for e + 's at the high end of their energy spectrum. By using the injector linac of Accelerator Test Facility at KEK and a commercially available Nd:YAG pulse laser, we can expect about 10 5 polarized e + 's per second with a degree of polarization of 80% and a kinetic energy of 35-80 MeV. The apparatus for creation and measurement of polarized e + 's is being constructed. We present new idea for possible application of our method to future linear colliders by utilizing a high-power CO 2 laser. (author)

Inner surface modification of a tube by magnetic glow-arc plasma source ion implantation

International Nuclear Information System (INIS)

Zhang Guling; Chinese Academy of Sciences, Beijing; Wang Jiuli; Feng Wenran; Chen Guangliang; Gu Weichao; Niu Erwu; Fan Songhua; Liu Chizi; Yang Size; Wu Xingfang

2006-01-01

A new method named the magnetic glow-arc plasma source ion implantation (MGA-PSII) is proposed for inner surface modification of tubes. In MGA-PSII, under the control of an axial magnetic field, which is generated by an electric coil around the tube sample, glow arc plasma moves spirally into the tube from its two ends. A negative voltage applied on the tube realized its inner surface implantation. Titanium nitride (TiN) films are prepared on the inner surface of a stainless steel tube in diameter 90 mm and length 600 mm. Hardness tests show that the hardness at the tube centre is up to 20 GPa. XRD, XPS and AES analyses demonstrate that good quality of TiN films can be achieved. (authors)

Inner Surface Modification of a Tube by Magnetic Glow-Arc Plasma Source Ion Implantation

Science.gov (United States)

Zhang, Gu-Ling; Wang, Jiu-Li; Wu, Xing-Fang; Feng, Wen-Ran; Chen, Guang-Liang; Gu, Wei-Chao; Niu, Er-Wu; Fan, Song-Hua; Liu, Chi-Zi; Yang, Si-Ze

2006-05-01

A new method named the magnetic glow-arc plasma source ion implantation (MGA-PSII) is proposed for inner surface modification of tubes. In MGA-PSII, under the control of an axial magnetic field, which is generated by an electric coil around the tube sample, glow arc plasma moves spirally into the tube from its two ends. A negative voltage applied on the tube realized its inner surface implantation. Titanium nitride (TiN) films are prepared on the inner surface of a stainless steel tube in diameter 90 mm and length 600 mm. Hardness tests show that the hardness at the tube centre is up to 20 GPa. XRD, XPS and AES analyses demonstrate that good quality of TiN films can be achieved.

Fluid model of dc glow discharge with nonlocal ionization source term

International Nuclear Information System (INIS)

Rafatov, I R; Bogdanov, E A; Kudryavtsev, A A

2012-01-01

We developed and tested a simple hybrid model for a glow discharge, which incorporates nonlocal ionization by fast electrons into the fluid framework. Calculations have been performed for an argon gas. Comparison with the experimental data as well as with the hybrid (particle) and fluid modelling results demonstated good applicability of the proposed model.

Electric field measurements at near-atmospheric pressure by coherent Raman scattering of laser beams

International Nuclear Information System (INIS)

Ito, Tsuyohito; Kobayashi, Kazunobu; Hamaguchi, Satoshi; Mueller, Sarah; Czarnetzki, Uwe

2010-01-01

Electric field measurements at near-atmospheric pressure environments based on electric-field induced Raman scattering are applied to repetitively pulsed nanosecond discharges. The results have revealed that the peak electric field near the centre of the gap is almost independent of the applied voltage. Minimum sustainable voltage measurements suggests that, at each discharge pulse, charged particles that remain from the previous pulse serve as discharge seeds and play an important role for generation of uniform glow-like discharges.

Effect of e-beam irradiation on graphene layer grown by chemical vapor deposition

International Nuclear Information System (INIS)

Iqbal, M. Z.; Kumar Singh, Arun; Iqbal, M. W.; Seo, Sunae; Eom, Jonghwa

2012-01-01

We have grown graphene by chemical vapor deposition (CVD) and transferred it onto Si/SiO 2 substrates to make tens of micron scale devices for Raman spectroscopy study. The effect of electron beam (e-beam) irradiation of various doses (600 to 12 000 μC/cm 2 ) on CVD grown graphene has been examined by using Raman spectroscopy. It is found that the radiation exposures result in the appearance of the strong disorder D band attributed the damage to the lattice. The evolution of peak frequencies, intensities, and widths of the main Raman bands of CVD graphene is analyzed as a function of defect created by e-beam irradiation. Especially, the D and G peak evolution with increasing radiation dose follows the amorphization trajectory, which suggests transformation of graphene to the nanocrystalline and then to amorphous form. We have also estimated the strain induced by e-beam irradiation in CVD graphene. These results obtained for CVD graphene are in line with previous findings reported for the mechanically exfoliated graphene [D. Teweldebrhan and A. A. Balandin, Appl. Phys. Lett. 94, 013101 (2009)]. The results have important implications for CVD graphene characterization and device fabrication, which rely on the electron microscopy.

Application of Glow Curve Deconvolution Method to Evaluate Low Dose TLD LiF

International Nuclear Information System (INIS)

Kurnia, E; Oetami, H R; Mutiah

1996-01-01

Thermoluminescence Dosimeter (TLD), especially LiF:Mg, Ti material, is one of the most practical personal dosimeter in known to date. Dose measurement under 100 uGy using TLD reader is very difficult in high precision level. The software application is used to improve the precision of the TLD reader. The objectives of the research is to compare three Tl-glow curve analysis method irradiated in the range between 5 up to 250 uGy. The first method is manual analysis, dose information is obtained from the area under the glow curve between pre selected temperature limits, and background signal is estimated by a second readout following the first readout. The second method is deconvolution method, separating glow curve into four peaks mathematically and dose information is obtained from area of peak 5, and background signal is eliminated computationally. The third method is deconvolution method but the dose is represented by the sum of area of peak 3,4 and 5. The result shown that the sum of peak 3,4 and 5 method can improve reproducibility six times better than manual analysis for dose 20 uGy, the ability to reduce MMD until 10 uGy rather than 60 uGy with manual analysis or 20 uGy with peak 5 area method. In linearity, the sum of peak 3,4 and 5 method yields exactly linear dose response curve over the entire dose range

Observation of an excess of νe, νe events in a beam dump experiment at 400 GeV

Directory of Open Access Journals (Sweden)

P. Alibran

1978-03-01

Full Text Available A beam dump experiment has been performed at CERN in Gargamelle using the neutrino facility to look for penetrating particles produced either directly in the beam interaction or by prompt decay of new particles. A total of 32 interactions with a visible energy greater than 10 GeV has been found, classified, aftercorrections, into 18 charged current νμ or νμ, 5.1 neutral current and 8.9 νe or νe charged current events. An excess of νe events remains after all subtractions from any established sources. Results are presented in terms of the product of the cross section and the leptonic decay branching ratio of the possible source.

Anode pattern formation in atmospheric pressure air glow discharges with water anode

NARCIS (Netherlands)

Verreycken, T.; Bruggeman, P.J.; Leys, C.

2009-01-01

Pattern formation in the anode layer at a water electrode in atmospheric pressure glow discharges in air is studied. With increasing current a sequence of different anode spot structures occurs from a constricted homogeneous spot in the case of small currents to a pattern consisting of small

Source of high-voltage power supply for ozone generators at glow discharge

International Nuclear Information System (INIS)

Bruev, A.A.; Golota, V.I.; Zavada, L.M.; Taran, G.V.

2000-01-01

High-voltage power supply source on quasi-resonance inverter base which works at direct current regime is described. This source forms 20 kV voltage with 0 - 10 mA current regulation. It protects the source from current break-downs and feeds ozone generators at glow discharge

Benchmarking the minimum Electron Beam (eBeam) dose required for the sterilization of space foods

Science.gov (United States)

Bhatia, Sohini S.; Wall, Kayley R.; Kerth, Chris R.; Pillai, Suresh D.

2018-02-01

As manned space missions extend in length, the safety, nutrition, acceptability, and shelf life of space foods are of paramount importance to NASA. Since food and mealtimes play a key role in reducing stress and boredom of prolonged missions, the quality of food in terms of appearance, flavor, texture, and aroma can have significant psychological ramifications on astronaut performance. The FDA, which oversees space foods, currently requires a minimum dose of 44 kGy for irradiated space foods. The underlying hypothesis was that commercial sterility of space foods could be achieved at a significantly lower dose, and this lowered dose would positively affect the shelf life of the product. Electron beam processed beef fajitas were used as an example NASA space food to benchmark the minimum eBeam dose required for sterility. A 15 kGy dose was able to achieve an approximately 10 log reduction in Shiga-toxin-producing Escherichia coli bacteria, and a 5 log reduction in Clostridium sporogenes spores. Furthermore, accelerated shelf life testing (ASLT) to determine sensory and quality characteristics under various conditions was conducted. Using Multidimensional gas-chromatography-olfactometry-mass spectrometry (MDGC-O-MS), numerous volatiles were shown to be dependent on the dose applied to the product. Furthermore, concentrations of off -flavor aroma compounds such as dimethyl sulfide were decreased at the reduced 15 kGy dose. The results suggest that the combination of conventional cooking combined with eBeam processing (15 kGy) can achieve the safety and shelf-life objectives needed for long duration space-foods.

On the feasibility of inversion methods based on models of urban sky glow

International Nuclear Information System (INIS)

Kolláth, Z.; Kránicz, B.

2014-01-01

Multi-wavelength imaging luminance photometry of sky glow provides a huge amount of information on light pollution. However, the understanding of the measured data involves the combination of different processes and data of radiation transfer, atmospheric physics and atmospheric constitution. State-of-the-art numerical radiation transfer models provide the possibility to define an inverse problem to obtain information on the emission intensity distribution of a city and perhaps the physical properties of the atmosphere. We provide numerical tests on the solvability and feasibility of such procedures. - Highlights: • A method of urban sky glow inversion is introduced based on Monte-Carlo calculations. • Imaging photometry can provide enough information for basic inversions. • The inversion technique can be used to construct maps of light pollution. • The inclusion of multiple scattering in the models plays an important role

Dynamic Mechanical Analysis of E-Beam and Thermally Curable IPN Thermosets

National Research Council Canada - National Science Library

Jensen, Robert

2002-01-01

... composites in a single step. Because of the complexity and thickness of composite integral armor structures, e-beam curing is an attractive processing method for Future Combat System applications, and the development...

Analysis of soils by glow discharge mass spectrometry

International Nuclear Information System (INIS)

Duckworth, D.C.; Barshick, C.M.; Smith, D.H.

1993-01-01

The analysis of soils by conventional solution-based techniques, such as inductively coupled plasma and thermal ionization mass spectrometry, is complicated by the need for sample dissolution or the combination of a solids atomizer with an auxiliary ionization source. Since time is an important consideration in waste remediation, there exists a need for a method of rapidly analysing many soil samples with little sample preparation; glow discharge mass spectrometry (GDMS) has the potential to meet this need. Because GDMS is a bulk solids technique, sample preparation is simplified in comparison to other methods. Even with the most difficult samples (geological materials, such as soils and volcanic rock), all that is required is grinding, drying and mixing with a conducting host material prior to electrode formation. As a first test of GDMS for soil analysis, a National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) was analysed by direct current GDMS. Fifty-one elements were quantified from a single cathode using ion beam ratios and ''standard'' relative elemental sensitivity factors (RSF). Average errors for the suite of elements were less than a factor of 4 and 1.4 for uncorrected and corrected values, respectively. User-generated RSF values were applied to the analysis of several elements in NIST SRM 2704 Buffalo River Sediment. In the absence of isobaric interferences, accuracies ranging from 0.6 to 73% were observed, demonstrating the potential of the technique for the determination of many elements. The presence of entrained water and inhomogeneity resulting from cathode preparation is thought to affect matrix-to-matrix reproducibility. While further success depends on developing means of circumventing mass spectral interferences and addressing factors affecting plasma chemistry, the immediate goal of developing a screening method for priority metals in soils was met. (Author)

Beam-beam issues in asymmetric colliders

International Nuclear Information System (INIS)

Furman, M.A.

1992-07-01

We discuss generic beam-beam issues for proposed asymmetric e + - e - colliders. We illustrate the issues by choosing, as examples, the proposals by Cornell University (CESR-B), KEK, and SLAC/LBL/LLNL (PEP-II)

Indium-tin-oxide thin film deposited by a dual ion beam assisted e-beam evaporation system

International Nuclear Information System (INIS)

Bae, J.W.; Kim, J.S.; Yeom, G.Y.

2001-01-01

Indium-tin-oxide (ITO) thin films were deposited on polycarbonate (PC) substrates at low temperatures (<90 deg. C) by a dual ion beam assisted e-beam evaporation system, where one gun (gun 1) is facing ITO flux and the other gun (gun 2) is facing the substrate. In this experiment, effects of rf power and oxygen flow rate of ion gun 2 on the electrical and optical properties of depositing ITO thin films were investigated. At optimal deposition conditions, ITO thin films deposited on the PC substrates larger than 20 cmx20 cm showed the sheet resistance of less than 40 Ω/sq., the optical transmittance of above 90%, and the uniformity of about 5%

Globalization and sustainable development an E7 point of view

Energy Technology Data Exchange (ETDEWEB)

Strassburg, W.

1998-07-01

The energy sector is a crucial feedstock to economic development. One example of this industry sector's contribution towards sustainable development is the so-called E7 initiative on sustainable energy development of some of the biggest electric utilities. E7 members from Canada, France, Germany, Italy, Japan and the US are demonstrating the functioning of the requested globally synchronized approach between developed and developing countries. E7 members focus their activities on (1) the efficient use of primary energy resources, (2) maximizing the use of renewable energy resources, (3) maximizing efficiency in the generation, delivery, and use of electricity, (4) minimizing environmental impacts of energy production and use and, (5) implementing innovative options to promote win-win benefits for the environment and the economy through their network of expertise on a pro bono basis. A main emphasis lies in the consistent Joint Implementation given the fact that innovative and efficient Green House Gas reduction measures will be the core of future E7 activities. Especially commercial projects will provide valuable contributions to Green House Gas reductions as well as to economic development of the recipient country. Other instruments, such Emission Trading and Clean Development Mechanism will have to be investigated appropriately in terms of their practicability for Green House Gas reductions so that their will be a notification by the international climate protection regime. Therefore Emission Trading and Clean Development Mechanism are of importance for E7 members' future operations, too. With respect to Sustainable Development industry, energy and environmental policy in leading industry countries must be more closely aligned to a global approach than has so far been the case. The electricity sector is called on to make a major contribution.

RIKEN RI Beam Factory and recent research activities

International Nuclear Information System (INIS)

Ueno, H.

2014-01-01

RIKEN has started the operation of the new facility for the Radioactive-Isotope Beam Factory (RIBF) project since 2006. In this project, intense primary beams are delivered at the energy E/A = 345 MeV over the whole range of the atomic number under the cyclotron-cascade acceleration scheme. The current, stability and sustainability in beam delivery have been increased significantly by recent improvement of the accelerator system. A high-current primary beam is then used to produce radioactive-isotope beams at the world's highest current utilizing the superconducting in-flight RI separator BigRIPS. Following the BigRIPS separator, several large-scale experimental key devices have been / will be installed, in order to fully capitalize the RIBF project. Owing to these progresses, nuclear structure information on far-unstable nuclei, which cannot be obtained by conventional technology, are now capable of being measured. Furthermore, in addition to such BigRIPS-related devices, other original experimental devices have been also newly installed at the lower energy experimental sites. Unique research opportunities are now available at the RIBF facility. (author)

e-Healthcare in India: critical success factors for sustainable health systems.

Science.gov (United States)

Taneja, Udita; Sushil

2007-01-01

As healthcare enterprises seek to move towards an integrated, sustainable healthcare delivery model an IT-enabled or e-Healthcare strategy is being increasingly adopted. In this study we identified the critical success factors influencing the effectiveness of an e-Healthcare strategy in India. The performance assessment criteria used to measure effectiveness were increasing reach and reducing cost of healthcare delivery. A survey of healthcare providers was conducted. Analytic Hierarchy Process (AHP) and Interpretive Structural Modeling (ISM) were the analytical tools used to determine the relative importance of the critical success factors in influencing effectiveness of e-Healthcare and their interplay with each other. To succeed in e-Healthcare initiatives the critical success factors that need to be in place are appropriate government policies, literacy levels, and telecommunications and power infrastructure in the country. The focus should not be on the IT tools and biomedical engineering technologies as is most often the case. Instead the nontechnology factors such as healthcare provider and consumer mindsets should be addressed to increase acceptance of, and enhance the effectiveness of, sustainable e-Healthcare services.

Properties of the positive column of a glow discharge in flowing hydrogen

International Nuclear Information System (INIS)

Brunet, H.; Rocca Serra, J.; Mabru, M.

1981-01-01

Results of a theoretical model for predicting the effects of gas flow on the properties of the positive column in a glow discharge are presented. A cylindrical discharge at low pressure ( 2 molecules and H atoms produced by the discharge are calculated. Comparison with available experimental data is made

Development of a wireless, self-sustaining damage detection sensor system based on chemiluminescence for structural health monitoring

Science.gov (United States)

Kuang, K. S. C.

2014-03-01

A novel application of chemiluminescence resulting from the chemical reaction in a glow-stick as sensors for structural health monitoring is demonstrated here. By detecting the presence of light emitting from these glow-sticks, it is possible to develop a low-cost sensing device with the potential to provide early warning of damage in a variety of engineering applications such as monitoring of cracks or damage in concrete shear walls, detecting of ground settlement, soil liquefaction, slope instability, liquefaction-related damage of underground structure and others. In addition, this paper demonstrates the ease of incorporating wireless capability to the sensor device and the possibility of making the sensor system self-sustaining by means of a renewable power source for the wireless module. A significant advantage of the system compared to previous work on the use of plastic optical fibre (POF) for damage detection is that here the system does not require an electrically-powered light source. Here, the sensing device, embedded in a cement host, is shown to be capable of detecting damage. A series of specimens with embedded glow-sticks have been investigated and an assessment of their damage detection capability will be reported. The specimens were loaded under flexure and the sensor responses were transmitted via a wireless connection.

Study of a contracted glow in low-frequency plasma-jet discharges operating with argon

Energy Technology Data Exchange (ETDEWEB)

Minotti, F.; Giuliani, L.; Xaubet, M.; Grondona, D. [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EHA, Buenos Aires, Argentina and Instituto de Física del Plasma (INFIP), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires - UBA, C1428EHA, Buenos Aires (Argentina)

2015-11-15

In this work, we present an experimental and theoretical study of a low frequency, atmospheric plasma-jet discharge in argon. The discharge has the characteristics of a contracted glow with a current channel of submillimeter diameter and a relatively high voltage cathode layer. In order to interpret the measurements, we consider the separate modeling of each region of the discharge: main channel and cathode layer, which must then be properly matched together. The main current channel was modeled, extending a previous work, as similar to an arc in which joule heating is balanced by lateral heat conduction, without thermal equilibrium between electrons and heavy species. The cathode layer model, on the other hand, includes the emission of secondary electrons by ion impact and by additional mechanisms, of which we considered emission due to collision of atoms excited at metastable levels, and field-enhanced thermionic emission (Schottky effect). The comparison of model and experiment indicates that the discharge can be effectively sustained in its contracted form by the secondary electrons emitted by collision of excited argon atoms, whereas thermionic emission is by far insufficient to provide the necessary electrons.

Parametric scaling studies of energy-confinement time for neutral-beam-heated Heliotron-E plasmas

International Nuclear Information System (INIS)

Sano, F.; Takeiri, Y.; Hanatani, K.

1989-02-01

Kinetic analysis of the global energy confinement time for neutral-beam-heated Heliotron-E plasmas has been performed with the 1-D, time-independent transport analysis code, PROCTR-Mod. Beam-power scans were performed by firing various number of hydrogen neutral beams, while density scans were performed by puffing gas and/or pellet fueling under the metallic or carbonized wall conditions. The wall carbonization facilitated the density increase due to the enhanced particle recycling on the walls, and also enabled long-pulse, quasi-stationary, currentless ECH + NBI operation with reduced heavy-impurity contamination. The data analysis shows that the favorable density dependence partially offsets the unfavorable power dependence, and that the anomalous electron transport loss becomes dominant in the over-all energy balance as the beam power and plasma density are increased. An alternative scaling law is also presented which is to fit τ E G [ms] by an 'offset-linear' law. The latter scaling is found to provide a better fit to the presented data sets in spite of its simple form. The parametric scaling of the local electron thermal diffusivity, χ e , is also discussed on the basis of the kinetic analysis. (J.P.N.)

Geometrical correction of the e-beam proximity effect for raster scan systems

Science.gov (United States)

Belic, Nikola; Eisenmann, Hans; Hartmann, Hans; Waas, Thomas

1999-06-01

Increasing demands on pattern fidelity and CD accuracy in e- beam lithography require a correction of the e-beam proximity effect. The new needs are mainly coming from OPC at mask level and x-ray lithography. The e-beam proximity limits the achievable resolution and affects neighboring structures causing under- or over-exposion depending on the local pattern densities and process settings. Methods to compensate for this unequilibrated does distribution usually use a dose modulation or multiple passes. In general raster scan systems are not able to apply variable doses in order to compensate for the proximity effect. For system of this kind a geometrical modulation of the original pattern offers a solution for compensation of line edge deviations due to the proximity effect. In this paper a new method for the fast correction of the e-beam proximity effect via geometrical pattern optimization is described. The method consists of two steps. In a first step the pattern dependent dose distribution caused by back scattering is calculated by convolution of the pattern with the long range part of the proximity function. The restriction to the long range part result in a quadratic sped gain in computing time for the transformation. The influence of the short range part coming from forward scattering is not pattern dependent and can therefore be determined separately in a second step. The second calculation yields the dose curve at the border of a written structure. The finite gradient of this curve leads to an edge displacement depending on the amount of underground dosage at the observed position which was previously determined in the pattern dependent step. This unintended edge displacement is corrected by splitting the line into segments and shifting them by multiples of the writers address grid to the opposite direction.

Enabling inspection solutions for future mask technologies through the development of massively parallel E-Beam inspection

Science.gov (United States)

Malloy, Matt; Thiel, Brad; Bunday, Benjamin D.; Wurm, Stefan; Jindal, Vibhu; Mukhtar, Maseeh; Quoi, Kathy; Kemen, Thomas; Zeidler, Dirk; Eberle, Anna Lena; Garbowski, Tomasz; Dellemann, Gregor; Peters, Jan Hendrik

2015-09-01

The new device architectures and materials being introduced for sub-10nm manufacturing, combined with the complexity of multiple patterning and the need for improved hotspot detection strategies, have pushed current wafer inspection technologies to their limits. In parallel, gaps in mask inspection capability are growing as new generations of mask technologies are developed to support these sub-10nm wafer manufacturing requirements. In particular, the challenges associated with nanoimprint and extreme ultraviolet (EUV) mask inspection require new strategies that enable fast inspection at high sensitivity. The tradeoffs between sensitivity and throughput for optical and e-beam inspection are well understood. Optical inspection offers the highest throughput and is the current workhorse of the industry for both wafer and mask inspection. E-beam inspection offers the highest sensitivity but has historically lacked the throughput required for widespread adoption in the manufacturing environment. It is unlikely that continued incremental improvements to either technology will meet tomorrow's requirements, and therefore a new inspection technology approach is required; one that combines the high-throughput performance of optical with the high-sensitivity capabilities of e-beam inspection. To support the industry in meeting these challenges SUNY Poly SEMATECH has evaluated disruptive technologies that can meet the requirements for high volume manufacturing (HVM), for both the wafer fab [1] and the mask shop. Highspeed massively parallel e-beam defect inspection has been identified as the leading candidate for addressing the key gaps limiting today's patterned defect inspection techniques. As of late 2014 SUNY Poly SEMATECH completed a review, system analysis, and proof of concept evaluation of multiple e-beam technologies for defect inspection. A champion approach has been identified based on a multibeam technology from Carl Zeiss. This paper includes a discussion on the

Period multiplication and chaotic phenomena in atmospheric dielectric-barrier glow discharges

International Nuclear Information System (INIS)

Wang, Y. H.; Zhang, Y. T.; Wang, D. Z.; Kong, M. G.

2007-01-01

In this letter, evidence of temporal plasma nonlinearity in which atmospheric dielectric-barrier discharges undergo period multiplication and chaos using a one-dimensional fluid model is reported. Under the conditions conducive for chaotic states, several frequency windows are identified in which period multiplication and secondary bifurcations are observed. Such time-domain nonlinearity is important for controlling instabilities in atmospheric glow discharges

Generalized eMC implementation for Monte Carlo dose calculation of electron beams from different machine types.

Science.gov (United States)

Fix, Michael K; Cygler, Joanna; Frei, Daniel; Volken, Werner; Neuenschwander, Hans; Born, Ernst J; Manser, Peter

2013-05-07

The electron Monte Carlo (eMC) dose calculation algorithm available in the Eclipse treatment planning system (Varian Medical Systems) is based on the macro MC method and uses a beam model applicable to Varian linear accelerators. This leads to limitations in accuracy if eMC is applied to non-Varian machines. In this work eMC is generalized to also allow accurate dose calculations for electron beams from Elekta and Siemens accelerators. First, changes made in the previous study to use eMC for low electron beam energies of Varian accelerators are applied. Then, a generalized beam model is developed using a main electron source and a main photon source representing electrons and photons from the scattering foil, respectively, an edge source of electrons, a transmission source of photons and a line source of electrons and photons representing the particles from the scrapers or inserts and head scatter radiation. Regarding the macro MC dose calculation algorithm, the transport code of the secondary particles is improved. The macro MC dose calculations are validated with corresponding dose calculations using EGSnrc in homogeneous and inhomogeneous phantoms. The validation of the generalized eMC is carried out by comparing calculated and measured dose distributions in water for Varian, Elekta and Siemens machines for a variety of beam energies, applicator sizes and SSDs. The comparisons are performed in units of cGy per MU. Overall, a general agreement between calculated and measured dose distributions for all machine types and all combinations of parameters investigated is found to be within 2% or 2 mm. The results of the dose comparisons suggest that the generalized eMC is now suitable to calculate dose distributions for Varian, Elekta and Siemens linear accelerators with sufficient accuracy in the range of the investigated combinations of beam energies, applicator sizes and SSDs.

Modeling of Pulsed Direct-Current Glow Discharge

International Nuclear Information System (INIS)

Du Mu; Zheng Yaru; Fan Yujia; Zhang Nan; Liu Chengsen; Wang Dezhen

2010-01-01

A self-consistent model was adopted to study the time evolution of low-voltage pulsed DC glow discharge. The distributions of electric field, ion density and electron density in nitrogen were investigated in our simulation, and the temporal shape of the discharge current was also obtained. Our results show that the dynamic behaviors of the discharge depends strongly on the applied pulse voltage, and the use of higher pulse voltages results in a significantly increase of discharge current and a decrease of discharge delay time. The current-voltage characteristic calculated by adjusting secondary electron emission coefficient for different applied pulse voltage under the gas pressure of 1 Torr is found in a reasonable agreement with the experimental results.

Glow discharge, its sensitivity to infra-red radiation. Observations made during the testing of multiwire proportional chambers

International Nuclear Information System (INIS)

Marsh, J.B.; Souten, K.H.; O'Hagan, B.

1979-05-01

It has been shown that under glow discharge conditions, multiwire proportional chambers are sensitive to infra-red radiation. Discharge current measurements and light change measurements have been made and the effect of the input window on the output signal and the importance of the finish of the anode and HT wires have been investigated. From these observations it would appear that a glow discharge in the form detailed in this report is sensitive to infra-red radiation though work is still required to optimise the parameters of such a device for IR detection or solar cell technology. (UK)

The hydrogen and oxygen content of self-supporting carbon foils prepared by dc glow discharge in ethylene

International Nuclear Information System (INIS)

Tait, N.R.S.; Tolfree, D.W.L.; John, P.; Odeh, I.M.; Thomas, M.J.K.; Tricker, M.J.; Wilson, J.J.B.; England, J.B.A.; Newton, D.

1980-01-01

The hydrogen and oxygen content of self-supporting carbon films produced by dc glow discharge have been determined using a precise method involving the elastic scattering of 25 MeV α-particles. The number of carbon-hydrogen bonds has been determined for similar samples using infrared spectroscopy. The results are compared with those for samples made by the carbon arc process. Assuming that the glow discharge carbon contains graphitic regions surrounded by amorphous tetrahedrally bonded material to which hydrogen can attach, a simple estimate is made of the relative numbers of carbon atoms in the two forms. (orig.)

Study relating to an e+e- storage ring of very high luminosity, with and without monochromatization of the beams (for the Tau-Charm Factory)

International Nuclear Information System (INIS)

Faus-Golfe, A.

1994-01-01

When two e + e - beams collide the effective luminosity is reduced due to the finite energy spread of each beam. If a scheme is used to separate the particle orbits, at the interaction point, with respect to their energy deviation, and with opposite polarities for the two beams, then a positron with energy (E+ΔE) will collide an electron with energy (E-ΔE). This allows an increase of the effective luminosity following a reduction of the energy spread in the CM. This original idea, though it was known since a long time, has never been experienced on existing machines. Since more recently, new e + e - circular colliders are being envisaged at energies already covered, but with design luminosities 2 or 3 orders of magnitude above past performances. These projects are called ''Factories'', and namely ''Tau-Charm Factory'' with 2.0 GeV beam energy and a luminosity of 10 33 cm -2 s -1 is being considered in Europe. Its performances can be enhanced using a monochromatization scheme, as described above. However the lack of past experience suggests to design the machine in such a way that a back up standard mode of operation is included from the beginning. The present study deals with optics developments which allow the two modes of operation within the same geometrical machine configuration. The corresponding lattices are called ''versatile''. (orig.)

Thermoluminescent characteristics of CaSO4:Dy+PTFE irradiated with high energy electron beams

International Nuclear Information System (INIS)

Alvarez, R.; Rivera, T.; Calderon, J. A.; Jimenez, Y.; Rodriguez, J.; Oviedo, O.; Azorin, J.

2011-10-01

In the present work thermoluminescent response of dysprosium doped calcium sulfate embedded in polytetrafluorethylene (CaSO 4 :Dy+PTFE) under high electron beam irradiations from linear accelerator for clinical applications was investigated. The irradiations were carried out using high electron beams (6 to 18 MeV) from a linear accelerator Varian, C linac 2300C/D, for clinical practice purpose. The electron irradiations were obtained by using the water solid in order to guarantee electronic equilibrium conditions. Field shaping for electron beams was obtained with electron cones. Glow curve and other thermoluminescent characteristics of CaSO 4 :Dy+PTFE were conducted under high electron beams irradiations. The thermoluminescent response of the pellets showed and intensity peak centered at around 235 C. Thermoluminescent response of CaSO 4 :Dy+PTFE as a function of high electron absorbed dose showed a linearity in a wide range. To obtain reproducibility characteristic, a set of pellets were exposed repeatedly for the same electron absorbed dose. The results obtained in this study can suggest the applicability of CaSO 4 :Dy+PTFE pellets for high electron beam dosimetry, provided fading is correctly accounted for. (Author)

Determination of trapping parameters of dosimetric thermoluminescent glow peak of lithium triborate (LiB{sub 3}O{sub 5}) activated by aluminum

Energy Technology Data Exchange (ETDEWEB)

Kafadar, V. Emir [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey); Yazici, A. Necmeddin, E-mail: yazici@gantep.edu.t [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey); Yildirim, R. Gueler [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey)

2009-07-15

Lithium triborate (LBO) is a newly developed ideal nonlinear optical (NLO) crystal used in laser weapon, welder, radar, tracker, surgery, communication, etc. The effective atomic number (Z{sub eff}=7.3) makes it a tissue equivalent material and this encourages studies on its thermoluminescence (TL) properties for a radiation dosimetry. The previous studies have shown that Al-doped LiB{sub 3}O{sub 5} is a promising thermoluminescent dosimetric (TLD) material for dosimetric purposes and continuous and systematic investigations to improve its quality to get ones suited for dosimeter applications are worthy. In the given study, the additive dose (AD), initial rise with partial cleaning (IR), variable heating rate (VHR), peak shape (PS), three-points method (TPM) and computerized glow deconvolution (CGCD) methods were used to determine the kinetic parameters, namely the order of kinetics (b), activation energy (E{sub a}) and the frequency factor (s) associated with the dosimetric thermoluminescent glow peak (P3) of Al-doped LiB{sub 3}O{sub 5} after different dose levels with beta-irradiation.

Applicability of the Child-Langmuir laws versions for describing the glow discharge cathode sheath in CO2

Science.gov (United States)

Lisovskiy, Valeriy; Krol, Hennadii; Osmayev, Ruslan; Yegorenkov, Vladimir

2016-09-01

This work is devoted to the determination of the law that may be applicable to the description of the cathode sheath in CO2. To this end three versions of the Child-Langmuir law have been considered - a collision free one (for the ions moving through a cathode sheath without collisions with gas molecules) as well as two collision- related versions- one for a constant mean free path of positive ions and one for a constant mobility of positive ions. The current-voltage characteristics and the cathode sheath thickness of the glow discharge in carbon oxide have been simultaneously measured in the pressure range from 0.05 to 1 Torr and with the discharge current values up to 80 mA. The inter-electrode distance has been chosen such that the discharge consists only of the cathode sheath and a small portion of the negative glow, i.e. the experiments have been performed in short tubes. In this case the voltage drop across the cathode sheath is equal approximately to the voltage drop across the electrodes. In the whole range of the discharge conditions we have studied the cathode sheath characteristics are found to obey correctly only to the Child-Langmuir law version with a constant ion mobility. The reason for this phenomenon may be related with a significant conversion of carbon dioxide molecules.

Study of Beam-Beam Effects at PEP-II

International Nuclear Information System (INIS)

Narsky, I

2004-01-01

Using a self-consistent three-dimensional simulation running on parallel supercomputers, we have modeled the beam-beam interaction at the PEP-II asymmetric e + e - collider. To provide guidance for luminosity improvement, we scanned the tunes and currents in both rings and computed their impact on the luminosity and transverse beam sizes. We also studied the effects of colliding the beams with a small crossing angle. Where possible, the code was benchmarked against experimental measurements of luminosity and beam sizes, yielding an acceptable agreement

Study on application of the physical detection methods for electron beam-irradiated agricultural products

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong Yong; Park, Yong Dae; Jin, Chang Hyun; Choi, Dae Seong; Jeong, Il Yun [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Yook, Hong Sun [Chungnam National University, Daejeon (Korea, Republic of)

2010-09-15

Physical detection methods, photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) were applied to detect electron beam-irradiated agricultural products, such as red pepper, black pepper, raisin, walnut, beef seasoning and pistachio. The absorbed irradiation doses for representative samples were controlled at 0, 1, 3, 5 and 10 kGy. PSL values for non-irradiated samples were <700 counts/60s (lower threshold, T{sub 1}) except beef seasoning, whereas those of irradiated samples were more than 5,000 photon counts, upper threshold (T{sub 2}) in black pepper, raisin, and beef seasoning and intermediates values of T{sub 1}-T{sub 2} in red pepper, walnut, and pistachio. Minerals separated from the samples for TL measurement showed that non-irradiated samples except pistachio (TL ratio, 0.12) were characterized by no glow curves situated at temperature range of 50 {approx} 400 .deg. C with TL ratio (0.01 {approx} 0.08), while irradiated samples except pistachio at only 1 kGy (TL ratio, 0.08) indicated glow curve at about 150 {approx} 250 .deg. C with TL ratio (0.28 {approx} 3.10). ESR measurements of irradiated samples any specific signals to irradiation. The samples of both red pepper ad pistachio were produced specific signals derived from cellulose radicals as well as single line signals for black pepper and walnut, and multiple signals derived from crystalline sugar radicals for raisin and beef seasoning. In conclusion, The ESR methods can apply for detection of pistachio exposed to electron beam but PSL and TL are not suitable methods. Furthermore, TL and ESR suggested that both techniques were more useful detection method than PSL to confirm whether red pepper, walnut and beef seasoning samples have been exposed to electron beam.

In-situ reactive glow discharge cleaning of NSLS distributed ion pumps

Energy Technology Data Exchange (ETDEWEB)

Johnson, E.D.; Chou, T.S.

1988-01-01

Based on our experience with the in-situ cleaning of optical systems by reactive r.f. glow discharges and the conditioning and preparation of distributed ion pump (DIP) elements, we have sought to develop strategies for recovering from severe vacuum accidents by restoring DIP elements of storage rings such as those at the NSLS in-situ. In this paper we will describe a series of experiments conducted in a test apparatus to condition a so called ''egg-crate'' DIP in-situ, (this older type element being common in older storage rings). A new untreated element which was unable to pump below 5x10 /sup /minus/8/ Torr in its initial condition was treated in oxygen and subsequent argon r.f. discharges utilizing the pump element as the discharge electrode producing a nitrogen pumping speed of 168 l/s at 2x10 /sup /minus/8/ Torr. A light bake at 75/degree/C increased this to nearly 500 l/s at 5x10 /sup /minus/8/ Torr. After exposure to atmosphere the speed was reduced to nil at these pressures but subsequently recovered, without bakeout, by glow discharge cleaning. 22 refs., 6 figs.

In-situ reactive glow discharge cleaning of NSLS distributed ion pumps

International Nuclear Information System (INIS)

Johnson, E.D.; Chou, T.S.

1988-01-01

Based on our experience with the in-situ cleaning of optical systems by reactive r.f. glow discharges and the conditioning and preparation of distributed ion pump (DIP) elements, we have sought to develop strategies for recovering from severe vacuum accidents by restoring DIP elements of storage rings such as those at the NSLS in-situ. In this paper we will describe a series of experiments conducted in a test apparatus to condition a so called ''egg-crate'' DIP in-situ, (this older type element being common in older storage rings). A new untreated element which was unable to pump below 5x10 /sup /minus/8/ Torr in its initial condition was treated in oxygen and subsequent argon r.f. discharges utilizing the pump element as the discharge electrode producing a nitrogen pumping speed of 168 l/s at 2x10 /sup /minus/8/ Torr. A light bake at 75/degree/C increased this to nearly 500 l/s at 5x10 /sup /minus/8/ Torr. After exposure to atmosphere the speed was reduced to nil at these pressures but subsequently recovered, without bakeout, by glow discharge cleaning. 22 refs., 6 figs

Formation and evolution of the glow-like dielectric barrier discharge at atmospheric pressure

NARCIS (Netherlands)

Starostin, S.A.; ElSabbagh, M.A.M.; Premkumar, P.A.; Vries, de H.W.; Paffen, R.M.J.; Creatore, M.; Sanden, van de M.C.M.

2008-01-01

Time resolved process of formation and evolution of the atmospheric pressure glow discharge was studied in the roll-to- roll plasma- enhanced chemical vapor deposition dielectric barrier discharge reactor operating in helium-free gas mixtures by means of fast ICCD imaging. It was observed that the

Thermoluminescence glow curve for UV induced ZrO2:Ti phosphor with variable concentration of dopant and various heating rate

Directory of Open Access Journals (Sweden)

Neha Tiwari

2014-10-01

Full Text Available The present paper reports the synthesis and characterization of Ti doped ZrO2 nanophosphors. The effects of variable concentration of titanium on thermoluminescence (TL behaviour are studied. The samples were prepared by combustion a synthesis technique which is suitable for less time taking techniques also for large scale production for nano phosphors. The starting material used for sample preparation are Zr(NO33 and Ti(NO33 and urea used as a fuel. The prepared sample was characterized by X-ray diffraction technique (XRD with variable concentration of Ti (0.05–0.5 mol% there is no any phase change found with increase the concentration of Ti. Sample shows cubic structure and the particle size calculated by Scherer's formula. The surface morphology of prepared phosphor was determined by field emission gun scanning electron microscopy (FEGSEM technique for optimized concentration of dopant. The good connectivity with grains and the semi-sphere like structure was found by FEGSEM. The functional group analysis was determined by Fourier transform infrared (FTIR spectroscopic techniques. The prepared phosphor examined by thermoluminescence technique. For recording TL glow curve every time 2 mg phosphor was irradiated by UV 254 nm source and fixed the heating rate at 5 °C s−1. Sample shows well resolved peak at 167 °C with a shoulder peak at 376 °C. The higher temperature peak shows the well stability and less fading in prepared phosphor. Also the effect of Ti concentration at fixed UV exposure time was studied. The effect of UV exposure time and dose versus intensity plot was studied. Sample shows linear response with dose and broaden peak with high temperature shows the more stability and less fading in TL glow curve. The linear dose response, high stability and less fading phenomenon shows the sample may be useful for thermoluminescence dosimetry application. Trapping parameters are calculated for every recorded glow curve. The

Out-of-Time Beam Extinction in the MU2E Experiment

Energy Technology Data Exchange (ETDEWEB)

Prebys, E. J. [Fermilab; Werkema, S. [Fermilab

2015-06-01

The Mu2e Experiment at Fermilab will search for the conversion of a muon to an electron in the field of an atomic nucleus with unprecedented sensitivity. The experiment requires a beam consisting of proton bunches 250 ns FW long, separated by 1.7 $\\mu$ sec, with no out-of-time protons at the $10^{10}$ fractional level. Satisfying this "extinction" requirement is very challenging. The formation of the bunches is expected to result in an extinction on the order of $10^5$. The remaining extinction will be accomplished by a system of resonant magnets and collimators, configured such that only in-time beam is delivered to the experiment. Our simulations show that the total extinction achievable by the system is on the order of $10^{12}$, with an efficiency for transmitting in-time beam of 99.6%.

Instability of compensated beam-beam collisions

International Nuclear Information System (INIS)

Rosenzweig, J.B.; Autin, B.; Chen, Pisin.

1989-01-01

The beam-beam disruption phenomena in linear colliders are increasingly seen as a source of serious problems for these machines. A plasma compensation scheme, in which the motion of the plasma electrons in the presence of the colliding beams provides neutralizing charge and current densities, has been proposed and studied. But natural alternative to this scheme is to consider the overlapping of nearly identical high energy e + and e/sup /minus// bunches, and the collision of two such pairs - in other words, collision of two opposing relativistic positronium plasmas. It should be noticed that while the luminosity for all collisions is increased by a factor of four in this scheme, the event rate for e + e/sup /minus// collisions is only increased by a factor of two. The other factor of two corresponds to the addition of e + e + and e/sup /minus//e/sup /minus// collisions to the interaction point. This beam compensation scheme, which has been examined through computer simulation by Balakin and Solyak in the Soviet Union, promises full neutralization of beam charges and currents. These numerical investigations have shown that plasma instabilities exist in this nominally neutral system. Although the implementation of this idea seems technically daunting, the potential benefits (beamstrahlung and disruption suppression, relaxation of final focus system constraints) are such that we should consider the physics of these collisions further. In the remainder of this paper, we theoretically analyze the issues of stability and bunch parameter tolerances in this scheme. 11 refs

Epitaxial GaN films by hyperthermal ion-beam nitridation of Ga droplets

Energy Technology Data Exchange (ETDEWEB)

Gerlach, J. W.; Ivanov, T.; Neumann, L.; Hoeche, Th.; Hirsch, D.; Rauschenbach, B. [Leibniz-Institut fuer Oberflaechenmodifizierung (IOM), D-04318 Leipzig (Germany)

2012-06-01

Epitaxial GaN film formation on bare 6H-SiC(0001) substrates via the process of transformation of Ga droplets into a thin GaN film by applying hyperthermal nitrogen ions is investigated. Pre-deposited Ga atoms in well defined amounts form large droplets on the substrate surface which are subsequently nitridated at a substrate temperature of 630 Degree-Sign C by a low-energy nitrogen ion beam from a constricted glow-discharge ion source. The Ga deposition and ion-beam nitridation process steps are monitored in situ by reflection high-energy electron diffraction. Ex situ characterization by x-ray diffraction and reflectivity techniques, Rutherford backscattering spectrometry, and electron microscopy shows that the thickness of the resulting GaN films depends on the various amounts of pre-deposited gallium. The films are epitaxial to the substrate, exhibit a mosaic like, smooth surface topography and consist of coalesced large domains of low defect density. Possible transport mechanisms of reactive nitrogen species during hyperthermal nitridation are discussed and the formation of GaN films by an ion-beam assisted process is explained.

Thermoluminescence of contaminating minerals for the detection of radiation treatment of dried fruits

Energy Technology Data Exchange (ETDEWEB)

Khan, H M; Bhatti, Ijaz A; Delincee, Henry

2002-03-01

Several types of dry fruits (pistachio nut, dried apricot, almond and raisins) have been investigated for detection of their radiation treatment by gamma rays or electron beam using thermoluminescence (TL) measurements. These samples were irradiated to 1.0-3.0 kGy (gamma rays) or 0.75-3.9 kGy (10 MeV electron beam). Thermoluminescence glow curves for the contaminating minerals separated from the dry fruits were recorded between the temperature range of 50 deg. C and 500 deg. C. In all the cases, the intensity of TL signal for the irradiated dry fruits was 1-3 orders of magnitudes higher than the TL intensity of the corresponding unirradiated control samples allowing clear distinction between the irradiated and unirradiated samples. These results were normalized by re-irradiating the mineral grains with a gamma-ray dose of 1.0 kGy, and a second glow curve was recorded. The ratio of intensity of the first glow curve (TL{sub 1}) to that after the normalization dose (TL{sub 2}), i.e. (TL{sub 1}/TL{sub 2}) was determined and compared with the recommended threshold values. These parameters, together with comparison of the shape of the first glow curve, gave unequivocal results about the radiation treatment of the dry fruit samples.

Thermoluminescence of contaminating minerals for the detection of radiation treatment of dried fruits

International Nuclear Information System (INIS)

Khan, H.M.; Bhatti, Ijaz A.; Delincee, Henry

2002-01-01

Several types of dry fruits (pistachio nut, dried apricot, almond and raisins) have been investigated for detection of their radiation treatment by gamma rays or electron beam using thermoluminescence (TL) measurements. These samples were irradiated to 1.0-3.0 kGy (gamma rays) or 0.75-3.9 kGy (10 MeV electron beam). Thermoluminescence glow curves for the contaminating minerals separated from the dry fruits were recorded between the temperature range of 50 deg. C and 500 deg. C. In all the cases, the intensity of TL signal for the irradiated dry fruits was 1-3 orders of magnitudes higher than the TL intensity of the corresponding unirradiated control samples allowing clear distinction between the irradiated and unirradiated samples. These results were normalized by re-irradiating the mineral grains with a gamma-ray dose of 1.0 kGy, and a second glow curve was recorded. The ratio of intensity of the first glow curve (TL 1 ) to that after the normalization dose (TL 2 ), i.e. (TL 1 /TL 2 ) was determined and compared with the recommended threshold values. These parameters, together with comparison of the shape of the first glow curve, gave unequivocal results about the radiation treatment of the dry fruit samples

Transition rate diagrams and excitation of titanium in a glow discharge in argon and neon

Science.gov (United States)

Weiss, Zdeněk; Steers, Edward B. M.; Pickering, Juliet C.

2018-06-01

Emission spectra of titanium in a Grimm-type glow discharge in argon and neon were studied using the formalism of transition rate diagrams. Ti I spectra in argon and neon discharges are similar, without signs of selective excitation, and populations of Ti I levels exhibit a decreasing trend as function of energy, except for some scatter. A major excitation process of Ti II in argon discharge is charge transfer from argon ions to neutral titanium. In neon discharge, a strong selective excitation was observed of Ti II levels at ≈13.3-13.4 eV relative to the Ti I ground state. It was attributed to charge transfer from doubly charged titanium ions to neutral titanium, while the Ti++ ions are produced by charge transfer and ionization of neutral titanium by neon ions. Cascade excitation is important for Ti II levels up to an energy of ≈13 eV relative to the Ti I ground state, both in argon and neon discharges.

Influence of an electric probe on the anode layer of a glow discharge in nitrogen

Science.gov (United States)

Taran, M. D.; Dyatko, N. A.; Kochetov, I. V.; Napartovich, A. P.; Akishev, Yu S.

2018-05-01

A two-dimensional (2D) numerical model of a DC glow discharge in nitrogen is developed for the case when the electric probe is mounted in the discharge gap. Within this model, calculations are performed for the gas pressure of 50 Torr and discharge current densities of 22 and 90 mA cm‑2. A cylindrical probe 1 mm in diameter is located parallel to the anode at a distance of 5 or 10 mm. The probe potential is varied in a wide range relative to the floating potential. Numerical simulations predict the 2D plasma perturbation pattern induced by the electric probe and the influence of the probe on anode layer characteristics. In particular, conditions are determined under which a region with no glow forms in the anode layer.

Simulation of the beam halo from the beam-beam interaction in LEP

International Nuclear Information System (INIS)

Chen, T.; Irwin, J.; Siemann, R.

1994-02-01

The luminosity lifetimes of e + e - colliders are often dominated by the halo produced by the beam-beam interaction. They have developed a simulation technique to model this halo using the flux across boundaries in amplitude space to decrease the CPU time by a factor of one-hundred or more over 'brute force' tracking. It allows simulation of density distributions and halos corresponding to realistic lifetimes. Reference 1 shows the agreement with brute force tracking in a number of cases and the importance of beam-beam resonances in determining the density distribution of large amplitudes. this research is now directed towards comparisons with operating colliders and studies of the combined effects of lattice and beam-beam nonlinearities. LEP offers an ideal opportunity for both, and in this paper they are presenting the first results of LEP simulations

An intense lithium ion beam source using vacuum baking and discharge cleaning techniques

International Nuclear Information System (INIS)

Moschella, J.J.; Kusse, B.R.; Longfellow, J.P.; Olson, J.C.

1991-01-01

We have developed a high-purity, intense, lithium ion beam source which operates at 500 kV and 120 A/cm 2 with pulse widths of 125 ns full width half maximum. The beams were generated using a lithium chloride anode in planar magnetically insulated geometry. We have found that the combination of vacuum baking of the anode at 250 degree C followed by the application of 100 W of pure argon, steady-state, glow discharge cleaning reduced the impurity concentration in the beam to approximately 10% (components other than chlorine or lithium were considered impurities). Although the impurities were low, the concentration of chlorine in the 1+ and 2+ charge states was significant (∼25%). The remaining 65% of the beam consisted of Li + ions. Without the special cleaning process, over half the beam particles were impurities. It was determined that these impurities entered the beam at the anode surface but came originally from material in the vacuum chamber. After the cleaning process, recontamination was observed to occur in approximately 6 min. This long recontamination time, which was much greater than the expected monolayer formation time, was attributed to the elevated temperature of the anode. We also compared the electrical characteristics of the beams produced by LiCl anodes to those generated by a standard polyethylene proton source. In contrast to the polyethylene anode, the LiCl source exhibited a higher impedance, produced beams of lower ion current efficiency and had longer turn on times

The structural design of an electron gun for an E-beam irradiator

International Nuclear Information System (INIS)

Yu Xiaojuan; Wu Xunlei; Jiang Zhenbo; Meng Mingfeng

2011-01-01

In this paper, an electron gun for a linac E-beam irradiator is developed with a replaceable cathode and filament. The structure of cathode and filament and the concentric technique, with molds and clamps, are described in detail. The electron gun was assembled with care to reduce the error, and ensure the concentricity of electron gun. The test results indicated a 99.99% pass ratio of the electron beams at 60-65 kV. The electron gun design meets the technical requirement of clients. (authors)

Aligned Carbon Nanotubes Array by DC Glow Plasma Etching for Supercapacitor

Directory of Open Access Journals (Sweden)

Yongfeng Luo

2013-01-01

Full Text Available To open the end of carbon nanotubes and make these ends connect with functional carboxyl group, aligned carbon nanotubes (CNTs arrays was etched by DC glow oxygen-argon plasma. With these open-ended carbon nanotubes array as electrode materials to build supercapacitor, we found that the capacity (32.2 F/g increased significantly than that of pure carbon nanotubes (6.7 F/g.

Tour operators, environment and sustainable development; Tour operator, ambiente e sviluppo sostenibile

Energy Technology Data Exchange (ETDEWEB)

Andriola, L.; Chirico, R.; Declich, P. [ENEA, Divisione Caratterizzazione dell' Ambiente e del Territorio, Centro Ricerche Casaccia, Rome (Italy)

2001-07-01

The purpose of this work is to characterize the role of the tour operators in achieving sustainable development meaning a process of development which leaves at least the same amount of capital, natural and man-made, to future generations as current generations have access to. Tourism is one of the largest and fastest growing global industries, creating significant employment and economic development, particularly in many developing countries. Tourism can also have negative environmental and social impact resulting from resource consumption, pollution, generation of wastes and from the compromise of local culture while introducing new activities. Most tour operators has started to recognised that a clean environment is critical to their success, but few tour operators have the management tools or experience to design and conduct tours that minimize their negative environmental and social impacts. A group of tour operators from different parts of the world have joined forces to create the Tour Operators' Initiative for Sustainable Tourism Development. With this initiatives, tour operators are moving towards sustainable tourism by committing themselves to address the environmental, social, and cultural aspects of sustainable development within the tourism sector. [Italian] Lo scopo del presente lavoro e' individuare il ruolo dei Tour Operator nel perseguire uno sviluppo sostenibile ossia un processo di sviluppo che lasci alle generazioni future lo stesso capitale, naturale e creato dall'uomo, di cui dispone l'attuale generazione. Il turismo e' tra le industrie globali piu' vaste ed in rapida crescita che crea una occupazione ed uno sviluppo economico significativo, particolarmente in molti paesi in via di sviluppo. Il turismo puo' anche generare impatti sia ambientali che sociali derivanti dallo sfruttamento delle risorse, dall'inquinamento, dalla produzione di rifiuti e dalla compromissione delle culture locali introducendo

Tour operators, environment and sustainable development; Tour operator, ambiente e sviluppo sostenibile

Energy Technology Data Exchange (ETDEWEB)

Andriola, L; Chirico, R; Declich, P [ENEA, Divisione Caratterizzazione dell' Ambiente e del Territorio, Centro Ricerche Casaccia, Rome (Italy)

2001-07-01

The purpose of this work is to characterize the role of the tour operators in achieving sustainable development meaning a process of development which leaves at least the same amount of capital, natural and man-made, to future generations as current generations have access to. Tourism is one of the largest and fastest growing global industries, creating significant employment and economic development, particularly in many developing countries. Tourism can also have negative environmental and social impact resulting from resource consumption, pollution, generation of wastes and from the compromise of local culture while introducing new activities. Most tour operators has started to recognised that a clean environment is critical to their success, but few tour operators have the management tools or experience to design and conduct tours that minimize their negative environmental and social impacts. A group of tour operators from different parts of the world have joined forces to create the Tour Operators' Initiative for Sustainable Tourism Development. With this initiatives, tour operators are moving towards sustainable tourism by committing themselves to address the environmental, social, and cultural aspects of sustainable development within the tourism sector. [Italian] Lo scopo del presente lavoro e' individuare il ruolo dei Tour Operator nel perseguire uno sviluppo sostenibile ossia un processo di sviluppo che lasci alle generazioni future lo stesso capitale, naturale e creato dall'uomo, di cui dispone l'attuale generazione. Il turismo e' tra le industrie globali piu' vaste ed in rapida crescita che crea una occupazione ed uno sviluppo economico significativo, particolarmente in molti paesi in via di sviluppo. Il turismo puo' anche generare impatti sia ambientali che sociali derivanti dallo sfruttamento delle risorse, dall'inquinamento, dalla produzione di rifiuti e dalla compromissione delle culture locali introducendo nuove attivita'. La maggiore parte dei

Unique heavy lepton signature at e{sup +}e{sup -} linear collider with polarized beams

Energy Technology Data Exchange (ETDEWEB)

Moortgat-Pick, G. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Osland, P. [Univ. Bergen (Norway). Dept. of Physics and Technology; Pankov, A.A.; Tsytrinov, A.V. [Technical Univ. Gomel (Belarus). Abdus Salam ICTP Affliated Centre

2013-03-15

We explore the effects of neutrino and electron mixing with exotic heavy leptons in the process e{sup +}e{sup -}{yields}W{sup +}W{sup -} within E{sub 6} models. We examine the possibility of uniquely distinguishing and identifying such effects of heavy neutral lepton exchange from Z-Z' mixing within the same class of models and also from analogous ones due to competitor models with anomalous trilinear gauge couplings (AGC) that can lead to very similar experimental signatures at the e{sup +}e{sup -} International Linear Collider (ILC) for {radical}(s)=350, 500 GeV and 1 TeV. Such clear identification of the model is possible by using a certain double polarization asymmetry. The availability of both beams being polarized plays a crucial role in identifying such exotic-lepton admixture. In addition, the sensitivity of the ILC for probing exotic-lepton admixture is substantially enhanced when the polarization of the produced W{sup {+-}} bosons is considered.

Hosing Instability of the Drive Electron Beam in the E157 Plasma-Wakefield Acceleration Experiment at the Stanford Linear Accelerator

International Nuclear Information System (INIS)

Blue, Brent Edward

2005-01-01

In the plasma-wakefield experiment at SLAC, known as E157, an ultra-relativistic electron beam is used to both excite and witness a plasma wave for advanced accelerator applications. If the beam is tilted, then it will undergo transverse oscillations inside of the plasma. These oscillations can grow exponentially via an instability know as the electron hose instability. The linear theory of electron-hose instability in a uniform ion column predicts that for the parameters of the E157 experiment (beam charge, bunch length, and plasma density) a growth of the centroid offset should occur. Analysis of the E157 data has provided four critical results. The first was that the incoming beam did have a tilt. The tilt was much smaller than the radius and was measured to be 5.3 (micro)m/(delta) z at the entrance of the plasma (IP1.) The second was the beam centroid oscillates in the ion channel at half the frequency of the beam radius (betatron beam oscillations), and these oscillations can be predicted by the envelope equation. Third, up to the maximum operating plasma density of E157 (∼2 x 10 14 cm -3 ), no growth of the centroid offset was measured. Finally, time-resolved data of the beam shows that up to this density, no significant growth of the tail of the beam (up to 8ps from the centroid) occurred even though the beam had an initial tilt

Hosing Instability of the Drive Electron Beam in the E157 Plasma-Wakefield Acceleration Experiment at the Stanford Linear Accelerator

Energy Technology Data Exchange (ETDEWEB)

Blue, Brent Edward; /SLAC /UCLA

2005-10-10

In the plasma-wakefield experiment at SLAC, known as E157, an ultra-relativistic electron beam is used to both excite and witness a plasma wave for advanced accelerator applications. If the beam is tilted, then it will undergo transverse oscillations inside of the plasma. These oscillations can grow exponentially via an instability know as the electron hose instability. The linear theory of electron-hose instability in a uniform ion column predicts that for the parameters of the E157 experiment (beam charge, bunch length, and plasma density) a growth of the centroid offset should occur. Analysis of the E157 data has provided four critical results. The first was that the incoming beam did have a tilt. The tilt was much smaller than the radius and was measured to be 5.3 {micro}m/{delta}{sub z} at the entrance of the plasma (IP1.) The second was the beam centroid oscillates in the ion channel at half the frequency of the beam radius (betatron beam oscillations), and these oscillations can be predicted by the envelope equation. Third, up to the maximum operating plasma density of E157 ({approx}2 x 10{sup 14} cm{sup -3}), no growth of the centroid offset was measured. Finally, time-resolved data of the beam shows that up to this density, no significant growth of the tail of the beam (up to 8ps from the centroid) occurred even though the beam had an initial tilt.

Effect of e-beam irradiation and microwave heating on the fatty acid composition and volatile compound profile of grass carp surimi

International Nuclear Information System (INIS)

Zhang, Hongfei; Wang, Wei; Wang, Haiyan; Ye, Qingfu

2017-01-01

In this study, we evaluated the effects of e-beam irradiationпј€1–7 kGyпј‰ and irradiation coupled to microwave heating (e-I-MC, 70 °C internal temperature) on the fatty acid composition and volatile compound profile of grass carp surimi. Compared to control samples, e-beam irradiation generated three novel volatile compounds (heptane, 2,6-dimethyl-nonane, and dimethyl disulfide) and increased the relative proportions of alcohols, aldehydes, and ketones. Meanwhile, e-I-MC significantly increased aldehyde levels and generated five heterocyclic compounds along with these three novel compounds. No significant difference in volatile compounds were detected in e-I-MC samples with increasing irradiation dose (p>0.05), comparing to the control group. E-beam irradiation at 5 and 7 kGy increased the levels of saturated fatty acids (SFAs) and decreased the levels of unsaturated fatty acids (p≤0.05), but did not affect the content of trans fatty acid levels (p>0.05). Irradiation, which had no significant effects on (Eicosapentaenoic acid) EPA, decreased (Docose Hexaenoie Acid) DHA levels. In the e-I-MC group, SFA levels increased and PUFA levels decreased. Additionally, MUFA levels were unaffected and trans fatty acid levels increased slightly following e-I-MC. - Highlights: • E-beam irradiation generated three novel volatile compounds. • E-beam irradiation increased the relative proportions of alcohols, aldehydes, and ketones. • E-beam irradiation coupled to microwave heating increased aldehyde levels and generated five heterocyclic compounds. • E-beam irradiation at 5 and 7 kGy decreased the levels of unsaturated fatty acids, but did not affect trans fatty acid levels.

Helicity description of e+e- → qanti qg and e+e- → Qanti Q(1--) → ggg on and off the Z0: quark, gluon and beam polarization effects

International Nuclear Information System (INIS)

Schiller, D.H.; Koerner, J.G.

1981-07-01

We develop the helicity description for the processes e + e - → qanti qg and e + e - → Qanti Q(1 -- ) → ggg(γgg) in the purely electromagnetic case, in the γ-Z 0 interference region and on the Z 0 -pole. We present complete differential cross section formulas including beam, quark and gluon polarization effects. We also treat the corresponding processes e + e - → qanti qS and e + e - → Qanti Q(1 -- ) → SSS(γSS) involving scalar gluons. (orig.)

New Opportunities for eBeam Technologies in One Health. Chapter 2

Energy Technology Data Exchange (ETDEWEB)

Pillai, S. D. [National Center for Electron Beam Research, Texas A& M University (United States)

2014-07-15

Globally, there is a growing recognition that, in order to address current and emerging risks and provide system-level solutions, one has to look at public health, animal health, and environmental health at a holistic level. Several international and federal agencies such as the United Nations, World Health Organization, the Centers for Disease Control and Prevention (CDC), and the United States Department of Agriculture (USDA) have come to embrace the One Health concept. The One Health concept is based on the premise that the health of humans, animals, and the environment are interconnected. Ionizing radiation technology, especially eBeam (electron beam) technology, can play a major role in providing solutions pertinent to the One Health concept. There can be no discussion of public health without confronting the issue of food safety and quality. There can be no discussion of animal health without tackling the pre-harvest pathogen protection strategies involving vaccination. And there can be no discussion of environmental health without discussing the proper management of the burgeoning levels of animal and human wastes. The salient features of eBeam technology such as high dose rate, economic feasibility, and that it is the ultimate “green technology”, can be exploited commercially to develop materials from natural and man-made sources that can be used for high value agricultural, industrial and therapeutic applications. (author)

Comparison of the response of various TLDs to cosmic radiation and ion beams: Current results of the HAMLET project

International Nuclear Information System (INIS)

Bilski, P.; Berger, T.; Hajek, M.; Reitz, G.

2011-01-01

HAMLET is an European Commission research project aiming at optimal scientific exploitation of the data produced within the space experiment MATROSHKA. During phase 1 of this experiment a human phantom equipped with several thousands of radiation detectors (mainly TLDs) was exposed outside the International Space Station for 1.5 years. Besides the measurements realized in Earth orbit, the HAMLET project includes also a ground-based program of intercomparison of detector response to high-energy ion beams. Within the paper, the relative response of main glow-curve peaks of various TLDs (mostly based on LiF) used in frame of the MATROSHKA experiment by three laboratories (DLR Cologne, ATI Vienna and IFJ Krakow) for radiation in space and several ion beams, has been compared. For LiF:Mg,Ti detectors a very good agreement between results obtained by the three laboratories was observed, both for space and accelerator-based exposures. This should be considered a remarkable result, taking into account that the studied TLDs originated from six different batches, manufactured by two producers exploiting different production techniques and were processed by three laboratories, using significantly different protocols (annealing, readout, calibration, glow-curve analysis). Another type of TL detectors, LiF:Mg,Cu,P, was found to show response to cosmic radiation lower than that of LiF:Mg,Ti by 5%–18%.

COATING AND MANDREL EFFECTS ON FABRICATION OF GLOW DISCHARGE POLYMER NIF SCALE INDIRECT DRIVE CAPSULES

International Nuclear Information System (INIS)

NIKROO, A.; PONTELANDOLFO, J.M.; CASTILLO, E.R.

2002-01-01

OAK A271 COATING AND MANDREL EFFECTS ON FABRICATION OF GLOW DISCHARGE POLYMER NIF SCALE INDIRECT DRIVE CAPSULES. Targets for the National Ignition Facility (NIF) need to be about 200 (micro)m thick and 2 mm in diameter. These dimensions are well beyond those currently fabricated on a routine basis. They have investigated fabrication of near NIF scale targets using the depolymerizable mandrel technique. Poly-alpha-methylstyrene (PAMS) mandrels, about 2 mm in diameter, of varying qualities were coated with as much as 125 (micro)m of glow discharge polymer (GDP). The surface finish of the final shells was examined using a variety of techniques. A clear dependence of the modal spectrum of final GDP shell on the quality of the initial PAMS mandrels was observed. isolated features were found to be the greatest cause for a shell not meeting the NIF standard

Comparison of the effects of gamma ray and e-beam irradiation on the quality of minced beef during storage

International Nuclear Information System (INIS)

Park, Jae Nam; Han, In Jun; Kim, Wang Geun; Song, Beom Seok; Kim, Jae Hun; Choi, Jong Il; Yoon, Yo Han; Byun, Myung Woo; Hwang, Han Joon; Lee, Ju Woon; Park, Jin Gyu

2009-01-01

This study was conducted to compare the microbiological and physicochemical qualities of minced beef irradiated with gamma ray of e-beam at the absorbed doses from 5 to 20 kGy. The total bacterial counts of minced beef were decreased depending upon the irradiation doses, but sterilizing effect of gamma irradiation was higher than that of e-beam irradiation. The contents of malondialdegyde of minced beef were increased depending upon irradiation doses as well as storage periods (p< 0.05). Volatile basic nitrogen in minced beef was constantly increased during storage, but the increasing rate were retarded by irradiation. The hunter's color values(L*, a* and b*) of gamma or e-beam irradiated minced beef were decreased as irradiation dose increasing. Meanwhile, the quality changes of gamma irradiated samples were faster than e-beam irradiated samples

Observation of an excess of nu$_{e}$, n$\\overline{u}_{e}$ events in a beam dump experiment at 400 GeV

CERN Document Server

Alibran, P; Arnold, R; Bartley, J H; Bellotti, E; Bertrand, D; Blaes, R; Blondel, A; Blum, D; Bolognese, T; Bonetti, S; Bonneaud, G R; Bourotte, J; Bullock, F W; Burmeister, H; Carnesecchi, G; Cavalli, D; Conforto, G; Degrange, B; Dewit, M; Erriquez, O; Escoubés, B; Fiorini, Ettore; Frodesen, A G; Gillespie, J; Haguenauer, Maurice; Heusse, P; Jacquet, F; Jones, T W; Lutz, A M; Matteuzzi, C; Morfín, J G; Muciaccia, M T; Musset, P; Natali, S; Nguyen-Khac, U; Nuzzo, S; Pascaud, C; Pattison, B; Paty, M; Petitjean, P; Price, M; Pullia, Antonio; Riester, J L; Rognebakke, A; Rollier, M; Romano, F; Sacton, J; Skjeggestad, O; Sleeman, J C; Van Doninck, W K; Vialle, J P; Weerts, H; Welch, L; Willutzky, M; Zanotti, L

1978-01-01

A beam dump experiment has been performed at CERN in Gargammelle using the neutrino facility to look for penetrating particles produced either directly in the beam interaction or by prompt decay of new particles. A total of 32 interactions with a visible energy greater than 10 GeV has been found, classified, after corrections, into 18 charged current nu /sub mu / or nu /sub mu /, 5.1 neutral current and 8.9 nu /sub e/ or nu /sub e/ charged current events. An excess of nu /sub e/ events remains after all subtractions from any established sources. Results are presented in terms of the product of the cross section and the leptonic decay branching ratio of the possible source. (11 refs).

Spatially Resolved Gas Temperature Measurements in an Atmospheric Pressure DC Glow Microdischarge with Raman Scattering

Science.gov (United States)

Belostotskiy, S.; Wang, Q.; Donnelly, V.; Economou, D.; Sadeghi, N.

2006-10-01

Spatially resolved rotational Raman spectroscopy of ground state nitrogen N2(X^1σg^+) was used to measure the gas temperature (Tg) in a nitrogen dc glow microdischarge (gap between electrodes d˜500 μm). An original backscattering, confocal optical system was developed for collecting Raman spectra. Stray laser light and Raleigh scattering were blocked by using a triple grating monochromator and spatial filters, designed specifically for these experiments. The optical system provided a spatial resolution of electrodes, Tg increased linearly with jd, reaching 500 K at 1000 mA/cm^2 jd for a pressure of 720 Torr. Spatially resolved gas temperature measurements will also be presented and discussed in combination with a mathematical model for gas heating in the microplasma. This work is supported by DoE/NSF.

KBr-Li Br and KBr-LiBr doped with Ti mixed single crystal by Czochralski method and glow curve studies

International Nuclear Information System (INIS)

Faripour, H.; Faripour, N.

2003-01-01

Mixed-single Crystals: pure KBr-LiBr and KBr-LiBr with Ti dopant were grown by Czochralski method. Because of difference between lattice parameters of KBr and LiBr, the growth speed of crystals were relatively low, and they were annealed in a special temperature condition providing some cleavages. They were exposed by β radiation and the glow curve was analysed for each crystal. Analysing of glow curve, showed that Ti impurity has been the curves of main peak curve appearance temperature decreasing

Fatal defect in computerized glow curve deconvolution of thermoluminescence

International Nuclear Information System (INIS)

Sakurai, T.

2001-01-01

The method of computerized glow curve deconvolution (CGCD) is a powerful tool in the study of thermoluminescence (TL). In a system where the plural trapping levels have the probability of retrapping, the electrons trapped at one level can transfer from this level to another through retrapping via the conduction band during reading TL. However, at present, the method of CGCD has no affect on the electron transition between the trapping levels; this is a fatal defect. It is shown by computer simulation that CGCD using general-order kinetics thus cannot yield the correct trap parameters. (author)

Use of glow discharge in measurement of diffusion profile

International Nuclear Information System (INIS)

Baudin, Guy

1976-05-01

The composition of a glow discharge plasma is a good image of the composition of the surface being erroded without fusion. The depth of metal eated away is a linear function of time in 10 to 60μ range, that is too say between 2 and 20 minutes after lightning of the lamp. So measuring the emission of the discharge is function of time gives the diffusion profile of elements either by measuring instantaneous signal or by integrating during short periods of time for weak concentration. Examples of application for diffusion of N 2 and C in steel will be given [fr

Analysing bifurcations encountered in numerical modelling of current transfer to cathodes of dc glow and arc discharges

International Nuclear Information System (INIS)

Almeida, P G C; Benilov, M S; Cunha, M D; Faria, M J

2009-01-01

Bifurcations and/or their consequences are frequently encountered in numerical modelling of current transfer to cathodes of gas discharges, also in apparently simple situations, and a failure to recognize and properly analyse a bifurcation may create difficulties in the modelling and hinder the understanding of numerical results and the underlying physics. This work is concerned with analysis of bifurcations that have been encountered in the modelling of steady-state current transfer to cathodes of glow and arc discharges. All basic types of steady-state bifurcations (fold, transcritical, pitchfork) have been identified and analysed. The analysis provides explanations to many results obtained in numerical modelling. In particular, it is shown that dramatic changes in patterns of current transfer to cathodes of both glow and arc discharges, described by numerical modelling, occur through perturbed transcritical bifurcations of first- and second-order contact. The analysis elucidates the reason why the mode of glow discharge associated with the falling section of the current-voltage characteristic in the solution of von Engel and Steenbeck seems not to appear in 2D numerical modelling and the subnormal and normal modes appear instead. A similar effect has been identified in numerical modelling of arc cathodes and explained.

Borax as flux on sintering of iron Ancor Steel 1000® under glow discharge

Science.gov (United States)

Ariza Suarez, H. G.; Sarmiento Santos, A.; Ortiz Otálora, C. A.

2016-02-01

This work studies the flux effect of borax (di sodium tetraborate decahydrate) on sintering of iron Ancor Steel 1000® in abnormal glow discharge. The incidence of the percentage by weight of borax and the sintering temperature in the process were observed. Samples of powder metallurgical iron were prepared with proportions of 0.50%, 2.0%, 4.0% and 6.0% by weight of borax using the procedures of powder metallurgy. The samples were sintered at 800 and 1100°C for 30min, by glow discharge at low pressure in a reducing atmosphere composed of 20% H2+80% Ar. The samples in compact green-state were analyzed by TGA-DSC to determine the fusion process and mass loss during sintering. The analysis of microhardness and density, shows that at a sintering temperature of 800°C the sample density decreases and the sample microhardness increases with respect to sintered samples without borax. Sintered samples were analysed by DRX showing the absence of precipitates.

Thermoluminescence response and glow curve structure of Sc2TiO5 ß-irradiated

International Nuclear Information System (INIS)

Muñoz, I.C.; Brown, F.; Durán-Muñoz, H.; Cruz-Zaragoza, E.; Durán-Torres, B.; Alvarez-Montaño, V.E.

2014-01-01

Discandium titanate (Sc 2 TiO 5 ) powder was synthesized in order to analyze its thermoluminescence (TL) response. The TL glow curve structure shows two peaks: at 453–433 K and at 590–553 K. The TL beta dose–response has a linear behavior over the dose range 50–500 Gy. The T stop preheat method shows five glow peaks that were taken into account to calculate the kinetic parameters using the CGCD procedure. TL results support the possible use of Sc 2 TiO 5 as a new phosphor in high ß-dose dosimetry. - Highlights: • Discandium titanate was synthesized, and its TL properties were analyzed. • The beta dose–response has a linear behavior on the dose range 50–500 Gy. • The kinetic parameters were obtained by the CGCD procedure. • Results support the possible use of Sc 2 TiO 5 as a new phosphor for ß-dose dosimetry

Microbial decontaminations of species by 10 MeV E- Beam

International Nuclear Information System (INIS)

Mehdizadeh Shahi, A.; Fallahnejad, N.

2005-01-01

Spices are used significantly in food industries. These substances contain high microbial contamination that causes the spoilage of the products and it is also hazardous for the health of consumers. Irradiation is one of the most effective methods to decontaminate spices. In this research , the optimum dose of e-beams to reduce microbial contamination of spices is determined. Samples of spices such as: turmeric, black pepper, garlic powder, onion powder, oregano and spice, were packaged in 10 grams, and they were irradiated at the dose of 0-10 kGy by 10 MeV e-beams. After irradiation, the total microbial counts were determined by the pour plating method. The bacterial contamination of different spices was between 10 5 to 4.7 x 10 7 cfu/gr and the molds count was between 1.8x10 2 to 7.2 x 10 3 cfu/gr. The survival curve of the bacteria was drawn in terms of bio burden versus the radiation dose rates. By determining the D 10 value, the minimum dose for reducing the spices microbial contamination up to the optimum limit, were identified

2D DC Subnormal Glow Discharge in Argon

International Nuclear Information System (INIS)

Bouchikhi, A.; Hamid, A.

2010-01-01

A two-dimensional time-dependent fluid model was developed and used to describe a DC subnormal glow discharge in argon with Cartesian geometry. This configuration allows us to take into account the transverse expansion of the discharge. A hydrodynamic fluid model used in this paper is based on the moments of the Boltzmann transport equation. The resultant set of governing equations consists of continuity equations (fluxes and densities) for electrons and ions, an energy equation for electrons, and Poisson's equation. Simulation results are presented for the densities of charged particles, the electric voltage, the electric field, and the electron temperature of the discharge. The results were compared with those obtained in the literature.

Low-energy electron beam proximity projection lithography (LEEPL): the world's first e-beam production tool, LEEPL 3000

Science.gov (United States)

Behringer, Uwe F. W.

2004-06-01

In June 2000 ago the company Accretech and LEEPL corporation decided to develop an E-beam lithography tool for high throughput wafer exposure, called LEEPL. In an amazing short time the alpha tool was built. In 2002 the beta tool was installed at Accretech. Today the first production tool the LEEPL 3000 is ready to be shipped. The 2keV E-beam tool will be used in the first lithography strategy to expose (in mix and match mode with optical exposure tools) critical levels like gate structures, contact holes (CH), and via pattern of the 90 nm and 65 nm node. At the SEMATECH EPL workshop on September 22nd in Cambridge, England it was mentioned that the amount of these levels will increase very rapidly (8 in 2007; 13 in 2010 and 17 in 2013). The schedule of the production tool for 45 nm node is mid 2005 and for the 32 nm node 2008. The Figure 1 shows from left to right α-tool, the β-tool and the production tool LEEPL 3000. Figure 1 also shows the timetable of the 4 LEEPL forum all held in Japan.

Computer code determination of tolerable accel current and voltage limits during startup of an 80 kV MFTF sustaining neutral beam source

International Nuclear Information System (INIS)

Mayhall, D.J.; Eckard, R.D.

1979-01-01

We have used a Lawrence Livermore Laboratory (LLL) version of the WOLF ion source extractor design computer code to determine tolerable accel current and voltage limits during startup of a prototype 80 kV Mirror Fusion Test Facility (MFTF) sustaining neutral beam source. Arc current limits are also estimated. The source extractor has gaps of 0.236, 0.721, and 0.155 cm. The effective ion mass is 2.77 AMU. The measured optimum accel current density is 0.266 A/cm 2 . The gradient grid electrode runs at 5/6 V/sub a/ (accel voltage). The suppressor electrode voltage is zero for V/sub a/ < 3 kV and -3 kV for V/sub a/ greater than or equal to 3 kV. The accel current density for optimum beam divergence is obtained for 1 less than or equal to V/sub a/ less than or equal to 80 kV, as are the beam divergence and emittance

A study on the equivalent electric circuit simulation model of DBD streamer and glow alternate discharge

International Nuclear Information System (INIS)

Yao, J; Zhang, Z T; Xu, S J; Yu, Q X; Yu, Z; Zhao, J S

2013-01-01

This paper presents a dynamic simulating model of the dielectric barrier discharge (DBD), structured as an equivalent electric circuit of the streamer and glow discharge generated alternately in DBD. The main parameters of DBD have been established by means of analysing the structural characteristics of a single discharge cell. An electrical comprehensive Simulink /MATLAB model was developed in order to reveal the interaction of the adjacent two discharge cell. A series of simulations was carried out in order to estimate the key structural parameters that affect the alternate streamer and glow discharge mode. The comparison results of experimental and simulate indicate that there exists a close similarity of the current waveforms graphic. Therefore, we can grasp a deep understanding mechanism of the dielectric barrier discharge and optimize the plasma reactor.

E-line: A new crystal collimator beam line for source size measurements at CHESS

International Nuclear Information System (INIS)

White, Jeffrey A.; Revesz, Peter; Finkelstein, Ken

2007-01-01

A new X-ray beam line has been constructed at cornell high energy synchrotron source (CHESS) to measure the vertical and horizontal source size of the positron particle beam. The cornell laboratory of elementary particle physics (LEPP) operates the storage ring (CESR) for X-ray generation for the CHESS user community by circulating electrons and their antimatter counterpart positrons in counter-rotating beams. As the laboratory reduces the emittances of particle beams to increase X-ray brilliance, there has been an increasing need for diagnostic tools to measure and monitor source size. A beam line front end that accesses the positron synchrotron light has been fitted with an experimental chamber and apparatus of compact design capable of horizontal and vertical source size measurement using the 'crystal collimator' technique, and an additional setup for vertical beam position monitoring using a luminescence-based X-ray video beam position monitoring system. The crystal collimators each consist of two Si(2 2 0) crystals in a dispersive (+,+) arrangement that diffract X-rays to a fluorescent material coated on a view port observed with a CCD camera. Measurements of the positron vertical beam size using the crystal collimation method at E-line are compared with measurements of visible synchrotron light at a remotely located dedicated port on the storage ring

Development of a Beam Trajectory Monitoring System Using e+/e− Pair Production Events

Directory of Open Access Journals (Sweden)

KIMURA Shota

2018-01-01

Full Text Available In particle therapy, it is important to monitor the Bragg-peak position. It was simulated by GEANT4 Monte Carlo Simulation Code that the distribution of secondary generated gamma rays on the carbon beam therapy and the proton beam therapy. This simulation shows that gamma rays whose energy is 10 MeV or more are intensively generated at the Bragg-peak position. We are developing the system to monitor the Bragg-peak position which can measure pair production events occurred in the detector by gamma rays from irradiation points. The momentum direction of the gamma ray can be determined by measuring passing points and energy of e+ and e− generated by pair production. This system has 5 parts. The first is the conversion part. This part consists of several layers. Each layer is composed of a La-GPS ((Gd0.75La0.24Ce0.012Si2O7 scintillator plate and wavelength-shifting fibre (WLSF sheets. The scintillator plate is sandwiched between sheets, where the directions of the sheets are in orthogonally x and y directions. In this part, gamma rays are converted to e+ e- pairs and the position where the conversion occured is determined. The second is the tracking part. This part consists of 2 layers of scintillating fibre tracker. Each layer has 6 scintillating fibre sheets for x, x’, u, u’, v, and v’. The third is the energy measurement part. It measures the energy of e+ and e− by scintillator array and Silicon Photomultipliers. The fourth is the veto counter for bremsstrahlung gamma rays from e+ and e-. The fifth is the beam monitor. By experiment, the number of photoelectrons of La-GPS with a WLSF (B-3(300MJ, Kuraray sheet and scintillating fibre (SCSF-78, Kuraray when charged particle passed was measured as 9.7 and 7.6 respectively.

Long-term deflection and flexural behavior of reinforced concrete beams with recycled aggregate

International Nuclear Information System (INIS)

Choi, Won-Chang; Yun, Hyun-Do

2013-01-01

Highlights: • Long-term deformation of recycled aggregate concrete beams was examined. • Three beams were monitored for over 380 days. • Influence of recycled aggregate on the long-term performance. • Comparison of that between normal and recycled aggregate concrete beams. - Abstract: This paper presents experimental results on the long-term deformations of recycled aggregate concrete (RAC) beams for over 1 year (380 days) and flexural behavior of RAC beams after exposure to sustained loading. Three reinforced concrete (RC) beam specimens were fabricated with replacement percentage of aggregate (100% natural aggregate, 100% recycled coarse aggregate, and 50% recycled fine aggregate) and subjected to sustained loading that is 50% of the nominal flexural capacity. During the sustained loading period (380 days), the long-term deflection due to creep and shrinkage was recorded and compared with predicted behavior that was determined based on current specifications (ACI 318 Code). After measuring the long-term deflection for 380 days, four-point bending tests were conducted to investigate the flexural behavior of RC beams after exposure to sustained loading and determine any reduction in flexural capacity. A modified equation to predict the long-term deflection values for RC beams with recycled aggregate is proposed, and the experimental results are compared with the predictions calculated using the ACI 318 Code provisions

Shock wave interaction with pulsed glow discharge and afterglow plasmas

International Nuclear Information System (INIS)

Podder, N.K.; LoCascio, A.C.

2009-01-01

Acoustic shock waves are launched by the spark-discharge of a high voltage capacitor in pulsed glow discharge and afterglow plasmas. The glow discharge section of the shock tube is switched on for a period of less than one second at a time, during which a shock wave is launched starting with a large delay between the plasma switch-on and the shock-launch. In the subsequent runs this delay is decremented in equal time intervals up to the plasma switch-on time. A photo acoustic deflection method sensitive to the density gradient of the shock wave is used to study the propagating shock structure and velocity in the igniting plasma. A similar set of measurements are also performed at the plasma switch-off, in which the delay time is incremented in equal time intervals from the plasma switch-off time until the afterglow plasma fully neutralizes itself into the room-temperature gas. Thus, complete time histories of the shock wave propagation in the igniting plasma, as well as in the afterglow plasma, are produced. In the igniting plasma, the changes in the shock-front velocity and dispersion are found to be a strong non-linear function of delay until a saturation point is reached. On the other hand, in the afterglow plasma the trend has been opposite and reversing towards the room temperature values. The observed shock wave properties in both igniting and afterglow plasmas correlate well with the inferred temperature changes in the two plasmas

Plasma based Ar+ beam assisted poly(dimethylsiloxane) surface modification

International Nuclear Information System (INIS)

Vladkova, T.G.; Keranov, I.L.; Dineff, P.D.; Youroukov, S.Y.; Avramova, I.A.; Krasteva, N.; Altankov, G.P.

2005-01-01

Plasma based Ar + beam performed in RF (13.56 MHz) low-pressure (200 mTorr) glow discharge (at 100 W, 1200 W and 2500 W) with a serial capacitance was employed for surface modification of poly(dimethylsiloxane) (PDMS) aimed at improvement of its interactions with living cells. The presence of a serial capacitance ensures arise of an ion-flow inside the plasma volume directed toward the treated sample and the vary of the discharge power ensures varied density of the ion-flow. XPS analysis was performed to study the changes in the surface chemical composition of the modified samples and the corresponding changes in the surface energy were monitored by contact angle measurements. We found that plasma based Ar + beam transforms the initially hydrophobic PDMS surface into a hydrophilic one mainly due to a raising of the polar component of the surface tension, this effect being most probably due to an enrichment of the modified surface layer with permanent dipoles of a [SiO x ]-based network and elimination of the original methyl groups. The initial adhesion of human fibroblast cells was studied on the described above plasma based Ar + beam modified and acrylic acid (AA) grafted or not fibronectin (FN) pre-coated or bare surfaces. The cell response seems to be related with the peculiar structure and wettability of the modified PDMS surface layer after plasma based Ar + beam treatment followed or not by AA grafting

Glow discharge processing vs bakeout for aluminum storage ring vacuum chambers

International Nuclear Information System (INIS)

Dean, N.R.; Hoyt, E.W.; Palrang, M.T.; Walker, B.G.

1977-11-01

Experiments were carried out on laboratory and prototype scale systems in order to establish the feasibility of argon discharge processing the PEP storage ring aluminum vacuum chambers. Electron-induced desorption rates showed significant reductions following bakeout and/or argon glow discharge treatment (>10 19 ions cm -1 ). Data are presented and discussed in relation to advantages and problems associated with: water removal, argon trapping and subsequent release, electron energy dependence, discharge distribution, and surface plasma chemical effects

Demonstration of electronic design automation flow for massively parallel e-beam lithography

Science.gov (United States)

Brandt, Pieter; Belledent, Jérôme; Tranquillin, Céline; Figueiro, Thiago; Meunier, Stéfanie; Bayle, Sébastien; Fay, Aurélien; Milléquant, Matthieu; Icard, Beatrice; Wieland, Marco

2014-07-01

For proximity effect correction in 5 keV e-beam lithography, three elementary building blocks exist: dose modulation, geometry (size) modulation, and background dose addition. Combinations of these three methods are quantitatively compared in terms of throughput impact and process window (PW). In addition, overexposure in combination with negative bias results in PW enhancement at the cost of throughput. In proximity effect correction by over exposure (PEC-OE), the entire layout is set to fixed dose and geometry sizes are adjusted. In PEC-dose to size (DTS) both dose and geometry sizes are locally optimized. In PEC-background (BG), a background is added to correct the long-range part of the point spread function. In single e-beam tools (Gaussian or Shaped-beam), throughput heavily depends on the number of shots. In raster scan tools such as MAPPER Lithography's FLX 1200 (MATRIX platform) this is not the case and instead of pattern density, the maximum local dose on the wafer is limiting throughput. The smallest considered half-pitch is 28 nm, which may be considered the 14-nm node for Metal-1 and the 10-nm node for the Via-1 layer, achieved in a single exposure with e-beam lithography. For typical 28-nm-hp Metal-1 layouts, it was shown that dose latitudes (size of process window) of around 10% are realizable with available PEC methods. For 28-nm-hp Via-1 layouts this is even higher at 14% and up. When the layouts do not reach the highest densities (up to 10∶1 in this study), PEC-BG and PEC-OE provide the capability to trade throughput for dose latitude. At the highest densities, PEC-DTS is required for proximity correction, as this method adjusts both geometry edges and doses and will reduce the dose at the densest areas. For 28-nm-hp lines critical dimension (CD), hole&dot (CD) and line ends (edge placement error), the data path errors are typically 0.9, 1.0 and 0.7 nm (3σ) and below, respectively. There is not a clear data path performance difference between

Evaluation of the glow curves of a new glass matrix

International Nuclear Information System (INIS)

Oliveira, Nathália S.; Souza, Samara P.; Ferreira, Pâmela Z.; Dantas, Noelio O.; Silva, Anielle C.A.; Neves, Lucio P.; Perini, Ana P.; Carrera, Betzabel N.S.; Watanabe, Shigueo

2017-01-01

Thermoluminescence is a dosimetric technique with may be used to personal, clinical, environmental and high doses. In this work a new glass matrix, with nominal composition of 20Li 2 CO 3 .10Al 2 O 3 .25BaO.45B 2 O 3 (mol%), was studied by the thermoluminescence technique. The glow curves was be analyzed, after the irradiation of this glass matrix with high doses. The results showed that this new glass matrix has a temperature peak in 260°C, which is ideal for dosimetry applications. (author)

The mechanism of nickel ferrite formation by glow discharge effect

Science.gov (United States)

Frolova, L. A.

2018-04-01

The influence of various factors on the formation of nickel ferrite by the glow discharge effect has been studied. The ferritization process in the system FeSO4-NiSO4-NaOH-H2O has been studied by the methods of potentiometric titration, measurement of electrical conductivity, residual concentrations and apparent sediment volume. It has been established that the process proceeds in a multistage fashion at pH 11-12 with the formation of polyhydroxo complexes, an intermediate compound and the ferrite formation by its oxidation with active radicals.

Glow discharge optical emission spectroscopy for accurate and well resolved analysis of coatings and thin films

KAUST Repository

Wilke, Marcus; Teichert, Gerd; Gemma, Ryota; Pundt, Astrid; Kirchheim, Reiner; Romanus, Henry; Schaaf, Peter

2011-01-01

overview on new developments in instrument design for accurate and well resolved thin film analyses is presented. The article focuses on the analytical capabilities of glow discharge optical emission spectrometry in the analysis of metallic coatings

Electron beam energy monitoring using thermoluminescent dosimeters and electron back scattering

International Nuclear Information System (INIS)

Nelson, Vinod; Gray, Alison

2013-01-01

Periodic checks of megavoltage electron beam quality are a fundamental requirement in ensuring accurate radiotherapy treatment delivery. In the present work, thermoluminescent dosimeters (TLDs) positioned on either side of a lead sheet at the surface of a water equivalent phantom were used to monitor electron beam quality using the electron backscattering method. TLD100 and TLD100H were evaluated as upstream detectors and TLD200, TLD400 and TLD500 were evaluated as downstream detectors. The evaluation assessed the test sensitivity and correlation, long and short term reproducibility, dose dependence and glow curve features. A prototype of an in-air jig suitable for use in postal TLD dose audits was also developed and an initial evaluation performed. The results indicate that the TLD100-TLD200 combination provides a sensitive and reproducible method to monitor electron beam quality. The light weight and easily fabricated in-air jig was found to produce acceptable results and has the potential to be used by radiation monitoring agencies to carry out TLD postal quality assurance audits, similar to audits presently being conducted for photon beams. -- Highlights: ► Monitoring electron beam quality via electron backscattering was investigated. ► Different thermoluminescent materials were evaluated as detectors. ► A TLD100-TLD200 combination produced the most sensitive and reproducible results. ► An in-air jig was evaluated to allow measurements via postal dose audits

Focusing of submicron beams for TeV-scale e+e- linear colliders

International Nuclear Information System (INIS)

Balakin, V.; Alexandrov, V.A.; Mikhailichenko, A.; Floettmann, K.; Peters, F.; Voss, G.; Bharadwaj, V.; Halling, M.; Holt, J.A.; Buon, J.; Jeanjean, J.; LeDiberder, F.; Lepeltier, V.; Puzo, P.; Heimlinger, G.; Settles, R.; Stierlin, U.; Hayano, H.; Ishihara, N.; Nakayama, H.; Oide, K.; Shintake, T.; Takeuchi, Y.; Yamamoto, N.; Bulos, F.; Burke, D.; Field, R.; Hartman, S.; Helm, R.; Irwin, J.; Iverson, R.; Rokni, S.; Roy, G.; Spence, W.; Tenenbaum, P.; Wagner, S.R.; Walz, D.; Williams, S.

1995-01-01

First experimental results from the final focus test beam (FFTB) are reported. The vertical dimension of a 47-GeV electron beam from the SLAC linac has been reduced at the focal point of the FFTB by a demagnification of 320 to a beam height of approximately 70 nm

The impact of molecular emission in compositional depth profiling using Glow Discharge-Optical Emission Spectroscopy

International Nuclear Information System (INIS)

Bengtson, Arne

2008-01-01

The scope of this paper is to investigate and discuss how molecular emission can affect elemental analysis in glow discharge optical emission (GD-OES), particularly in compositional depth profiling (CDP) applications. Older work on molecular emission in glow discharges is briefly reviewed, and the nature of molecular emission spectra described. Work on the influence of hydrogen in the plasma, in particular elevated background due to a continuum spectrum, is discussed. More recent work from sputtering of polymers and other materials with a large content of light elements in a Grimm type source is reviewed, where substantial emission has been observed from several light diatomic molecules (CO, CH, OH, NH, C 2 ). It is discussed how the elevated backgrounds from such molecular emission can lead to significant analytical errors in the form of 'false' depth profile signals of several atomic analytical lines. Results from a recent investigation of molecular emission spectra from mixed gases in a Grimm type glow discharge are presented. An important observation is that dissociation and subsequent recombination processes occur, leading to formation of molecular species not present in the original plasma gas. Experimental work on depth profiling of a polymer coating and a thin silicate film, using a spectrometer equipped with channels for molecular emission lines, is presented. The results confirm that molecular emission gives rise to apparent depth profiles of elements not present in the sample. The possibilities to make adequate corrections for such molecular emission in CDP of organic coatings and very thin films are discussed

The impact of molecular emission in compositional depth profiling using Glow Discharge-Optical Emission Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Bengtson, Arne [Corrosion and Metals Research Institute, Dr. Kristinas vaeg 48, Stockholm (Sweden)], E-mail: arne.bengtson@kimab.com

2008-09-15

The scope of this paper is to investigate and discuss how molecular emission can affect elemental analysis in glow discharge optical emission (GD-OES), particularly in compositional depth profiling (CDP) applications. Older work on molecular emission in glow discharges is briefly reviewed, and the nature of molecular emission spectra described. Work on the influence of hydrogen in the plasma, in particular elevated background due to a continuum spectrum, is discussed. More recent work from sputtering of polymers and other materials with a large content of light elements in a Grimm type source is reviewed, where substantial emission has been observed from several light diatomic molecules (CO, CH, OH, NH, C{sub 2}). It is discussed how the elevated backgrounds from such molecular emission can lead to significant analytical errors in the form of 'false' depth profile signals of several atomic analytical lines. Results from a recent investigation of molecular emission spectra from mixed gases in a Grimm type glow discharge are presented. An important observation is that dissociation and subsequent recombination processes occur, leading to formation of molecular species not present in the original plasma gas. Experimental work on depth profiling of a polymer coating and a thin silicate film, using a spectrometer equipped with channels for molecular emission lines, is presented. The results confirm that molecular emission gives rise to apparent depth profiles of elements not present in the sample. The possibilities to make adequate corrections for such molecular emission in CDP of organic coatings and very thin films are discussed.

Doppler spectroscopy of hydrogen Balmer lines in a hollow cathode glow discharge in ammonia and argon-ammonia mixture

International Nuclear Information System (INIS)

Sisovic, N. M.; Konjevic, N.

2008-01-01

The results of Doppler spectroscopy of hydrogen Balmer lines from a stainless steel (SS) and copper (Cu) hollow cathode (HC) glow discharge in ammonia and argon-ammonia mixture are reported. The experimental profiles in ammonia discharge are fitted well by superposing three Gaussian profiles. The half widths, in energy units, of narrow and medium Gaussians are in the ranges 0.3-0.4 eV and 3-4 eV, respectively, for both hollow cathodes what is expected on the basis of earlier electron beam→NH 3 experiments. The half widths of the largest Gaussian in ammonia are 46 and 55 eV for SS and Cu HC, respectively. In argon-ammonia discharge, three Gaussians are also required to fit experimental profiles. While half widths of narrow and medium Gaussians are similar to those in ammonia, the half widths of the largest Gaussians are 35 and 42 eV for SS and Cu HC, respectively. The half widths of the largest Gaussians in ammonia and in argon-ammonia mixture indicate the presence of excessive Doppler broadening.

Decomposition of toluene in a steady-state atmospheric-pressure glow discharge

International Nuclear Information System (INIS)

Trushkin, A. N.; Grushin, M. E.; Kochetov, I. V.; Trushkin, N. I.; Akishev, Yu. S.

2013-01-01

Results are presented from experimental studies of decomposition of toluene (C 6 H 5 CH 3 ) in a polluted air flow by means of a steady-state atmospheric pressure glow discharge at different water vapor contents in the working gas. The experimental results on the degree of C 6 H 5 CH 3 removal are compared with the results of computer simulations conducted in the framework of the developed kinetic model of plasma chemical decomposition of toluene in the N 2 : O 2 : H 2 O gas mixture. A substantial influence of the gas flow humidity on toluene decomposition in the atmospheric pressure glow discharge is demonstrated. The main mechanisms of the influence of humidity on C 6 H 5 CH 3 decomposition are determined. The existence of two stages in the process of toluene removal, which differ in their duration and the intensity of plasma chemical decomposition of C 6 H 5 CH 3 is established. Based on the results of computer simulations, the composition of the products of plasma chemical reactions at the output of the reactor is analyzed as a function of the specific energy deposition and gas flow humidity. The existence of a catalytic cycle in which hydroxyl radical OH acts a catalyst and which substantially accelerates the recombination of oxygen atoms and suppression of ozone generation when the plasma-forming gas contains water vapor is established.

Decomposition of toluene in a steady-state atmospheric-pressure glow discharge

Science.gov (United States)

Trushkin, A. N.; Grushin, M. E.; Kochetov, I. V.; Trushkin, N. I.; Akishev, Yu. S.

2013-02-01

Results are presented from experimental studies of decomposition of toluene (C6H5CH3) in a polluted air flow by means of a steady-state atmospheric pressure glow discharge at different water vapor contents in the working gas. The experimental results on the degree of C6H5CH3 removal are compared with the results of computer simulations conducted in the framework of the developed kinetic model of plasma chemical decomposition of toluene in the N2: O2: H2O gas mixture. A substantial influence of the gas flow humidity on toluene decomposition in the atmospheric pressure glow discharge is demonstrated. The main mechanisms of the influence of humidity on C6H5CH3 decomposition are determined. The existence of two stages in the process of toluene removal, which differ in their duration and the intensity of plasma chemical decomposition of C6H5CH3 is established. Based on the results of computer simulations, the composition of the products of plasma chemical reactions at the output of the reactor is analyzed as a function of the specific energy deposition and gas flow humidity. The existence of a catalytic cycle in which hydroxyl radical OH acts a catalyst and which substantially accelerates the recombination of oxygen atoms and suppression of ozone generation when the plasma-forming gas contains water vapor is established.

Dependence of electron beam instability growth rates on the beam-plasma system parameters

International Nuclear Information System (INIS)

Strangeway, R.J.

1982-01-01

Electron beam instabilites are studied by using a simple model for an electron beam streaming through a cold plasma, the beam being of finite width perpendicular to the ambient magnetic field. Through considerations of finite geometry and the coldness of the beam and background plasma, an instability similar to the two stream instability is assumed to be the means for wave growth in the system. Having found the maximum growth rate for one set of beam-plasma system parameters, this maximum growth rate is traced as these parameters are varied. The parameters that describe the system are the beam velocity (v/sub b/), electron gyrofrequency to ambient electron plasma frequency ratio (Ω/sub e//ω/sub p/e), the beam to background number density ratio (n/sub b//n/sub a/), and the beam width (a). When Ω/sub e//ω/sub p/e>1, a mode with Ω/sub e/<ω<ω/sub u/hr is found to be unstable, where Ω is the wave frequency and ω/sub u/hr is the upper hybrid resonance frequency. For low values of n/sub b//n/sub a/ and Ω/sub e/<ω/sub p/e, this mode is still present with ω/sub p/e<ω<ω/sub u/hr. If the beam density is large, n/sub b//n/sub a/approx. =1, the instability occures for frequencies just above the electron gyrofrequency. This mode may well be that observed in laboratory plasma before the system undergoes the beam-plasma discharge. There is another instability present, which occurs for ωapprox. =ω/sub p/e. The growth rates for this mode, which are generally larger than those found for the ωapprox. =ωuhr mode, are only weakly dependent on Ω/sub d//ω/sub p/e. That this mode is not always observed in the laboratory implies that some factors not considered in the present theory suppress this mode, specifically, finite beam length

Epitaxial Ni films, e-beam nano-patterning and BMR

Science.gov (United States)

Lukaszew, R. Alejandra; Zhang, Zhengdong; Pearson, Dave; Zambano, Antonio

2004-05-01

We have attempted to clarify possible domain-wall processes present in the recently reported large ballistic magnetoresistance effects in nano-contacts. To that effect we have used e-beam lithography applied to epitaxial Ni films to fabricate nano-bridges in more controlled geometry than electrochemical deposition. Our preliminary results indicate that magnetic domains do play a role in the magneto-resistance of these nano-bridges but the order of magnitude of the observed effect is considerably smaller than the reported observations in electrochemically prepared nano-contacts.

Epitaxial Ni films, e-beam nano-patterning and BMR

International Nuclear Information System (INIS)

Lukaszew, R.A.; Zhang Zhengdong; Pearson, Dave; Zambano, Antonio

2004-01-01

We have attempted to clarify possible domain-wall processes present in the recently reported large ballistic magnetoresistance effects in nano-contacts. To that effect we have used e-beam lithography applied to epitaxial Ni films to fabricate nano-bridges in more controlled geometry than electrochemical deposition. Our preliminary results indicate that magnetic domains do play a role in the magneto-resistance of these nano-bridges but the order of magnitude of the observed effect is considerably smaller than the reported observations in electrochemically prepared nano-contacts

E-line: A new crystal collimator beam line for source size measurements at CHESS

Energy Technology Data Exchange (ETDEWEB)

White, Jeffrey A. [CHESS, Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY 14850-8001 (United States)], E-mail: jaw7@cornell.edu; Revesz, Peter; Finkelstein, Ken [CHESS, Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY 14850-8001 (United States)

2007-11-11

A new X-ray beam line has been constructed at cornell high energy synchrotron source (CHESS) to measure the vertical and horizontal source size of the positron particle beam. The cornell laboratory of elementary particle physics (LEPP) operates the storage ring (CESR) for X-ray generation for the CHESS user community by circulating electrons and their antimatter counterpart positrons in counter-rotating beams. As the laboratory reduces the emittances of particle beams to increase X-ray brilliance, there has been an increasing need for diagnostic tools to measure and monitor source size. A beam line front end that accesses the positron synchrotron light has been fitted with an experimental chamber and apparatus of compact design capable of horizontal and vertical source size measurement using the 'crystal collimator' technique, and an additional setup for vertical beam position monitoring using a luminescence-based X-ray video beam position monitoring system. The crystal collimators each consist of two Si(2 2 0) crystals in a dispersive (+,+) arrangement that diffract X-rays to a fluorescent material coated on a view port observed with a CCD camera. Measurements of the positron vertical beam size using the crystal collimation method at E-line are compared with measurements of visible synchrotron light at a remotely located dedicated port on the storage ring.

Optimizing the e-beam profile of a single carbon nanotube field emission device for electric propulsion systems

Directory of Open Access Journals (Sweden)

Juliano Fujioka Mologni

2010-04-01

Full Text Available Preliminary studies on field emission (FE arrays comprised of carbon nanotubes (CNT as an electron source for electric propulsion system show remarkably promising results. Design parameters for a carbon nanotube (CNT field-emission device operating on triode configuration were numerically simulated and optimized in order to enhance the e-beam focusing quality. An additional focus gate (FG was integrated to the device to control the profile of the emitted e-beam. An axisymmetric finite element model was developed to calculate the electric field distribution on the vacuum region and a modified Fowler-Nordheim (FN equation was used to evaluate the current density emission and the effective emitter area. Afterward, a FE simulation was employed in order to calculate the trajectory of the emitted electrons and define the electron-optical properties of the e-beam. The integration of the FG was fully investigated via computational intelligence techniques. The best performance device according to our simulations presents a collimated e-beam profile that suits well for field emission displays, magnetic field detection and electron microscopy. The automated computational design tool presented in this study strongly benefits the robust design of integrated electron-optical systems for vacuum field emission applications, including electrodynamic tethering and electric propulsion systems.

DC negative corona discharge in atmospheric pressure helium: transition from the corona to the ‘normal’ glow regime

International Nuclear Information System (INIS)

Hasan, Nusair; Farouk, Bakhtier; Antao, Dion S

2014-01-01

Direct current (dc) negative corona discharges in atmospheric pressure helium are simulated via detailed numerical modeling. Simulations are conducted to characterize the discharges in atmospheric helium for a pin plate electrode configuration. A self-consistent two-dimensional hybrid model is developed to simulate the discharges and the model predictions are validated with experimental measurements. The discharge model considered consists of momentum and energy conservation equations for a multi-component (electrons, ions, excited species and neutrals) gas mixture, conservation equations for each component of the mixture and state relations. A drift–diffusion approximation for the electron and the ion fluxes is used. A model for the external circuit driving the discharge is also considered and solved along with the discharge model. Many of the key features of a negative corona discharge, namely non-linear current–voltage characteristics, spatially flat cathode current density and glow-like discharge in the high current regime are displayed in the predictions. A transition to the ‘normal’ glow discharge from the corona discharge regime is also observed. The transition is identified from the calculated current–voltage characteristic curve and is characterized by the radial growth of the negative glow and the engulfment of the cathode wire. (paper)

E-CITY KNOWWARE: KNOWLEDGE MIDDLEWARE FOR COORDINATED MANAGEMENT OF SUSTAINABLE CITIES

Directory of Open Access Journals (Sweden)

Tamer E. El-Diraby

2009-12-01

Full Text Available The realization of e-city is a necessary component for achieving the green city. This paper outlines a vision for an e-city platform that is based on knowledge brokerage in the green city. The proposed platform will be a venue for creating dynamic virtual organizations to harness collective intelligence of knowledge hubs to analyze and manage sustainability knowledge in urban areas. Knowledge assets of participating organizations will be presented in three dimensions: process structures, human profile and software systems. These three facets of knowledge will be accessible and viewable through a self-describing mechanism. Cities can post their geospatial and real-time data on the net. Relevant environmental and energy-use data will be extracted using topic maps and data extraction services. Local decision makers can synchronize work processes (from participating hubs to create an integrated workflow for a new ad hoc virtual organization to collaboratively analyze the multifaceted nature of sustainable decision making. An e-city platform is envisioned in this paper that will be realized through intelligent, agent-like, domain-specific middleware (KnowWare. Through triangulation between people, software and processes, these KnowWare will discover, negotiate, integrate, reason and communicate knowledge (related to energy and environment from across organizations to the right person at the right time. KnowWare is fundamentally, a portal of social semantic services that resides on a cloud computing infrastructure. Knowware exploits thee main tools: 1 existing ontologies to represent knowledge in a semantic manner, 2 topic maps to profile sources of knowledge and match these to the complex needs of sustainability analysis, 3 domain-specific middleware for knowledge integration and reasoning.

An influence of ion and sputtered atom flows inhomogeneity on time evolution of the target surface relief in glow discharge

International Nuclear Information System (INIS)

Bondarenko, G G; Kristya, V I

2008-01-01

A mathematical model of ion and sputtered atom transport in the vicinity of the target with a periodical surface relief in glow discharge in pure gas is developed. Under the assumption that the relief amplitude is small, analytical expressions for their flows are found by the perturbation method and an equation describing the relief amplitude time evolution is derived. It is shown that intensity of sputtering exceeds intensity of sputtered material re-deposition at the relief tops, and relief smoothing always takes place in the process of homogeneous target treatment in glow discharge in pure gas

Development of a wood-polymer composite by electron beam hardening

International Nuclear Information System (INIS)

Gotoda, Masao

1974-01-01

An incombustible wood-polymer composite (WPC) was studied. The dimensional stability was also tested. The comparison of conversion ratio was made between gamma-ray and electron beam and between a vinylidene chloride 100% impregnated beech composite and bulk. In the case of gamma-ray of low dose rate, the conversion ratio in the vinylidene chloride beech composite was lower than the bulk. In the case of electron beam, though dose rate was higher than that of gamma-ray, the conversion ratio was low, and was influenced by the moisture content of wood. The conversion ratio markedly decreased with the increase of the dose rate of electron beam. Roughly 50% polymer loading can be obtained when the dose rate of electron beam is low. In the case of gamma-ray, the effect of dimensional stability was approximately none with small polymer loading, whereas in the case of electron beam irradiation of moist wood, marked effect of dimensional stability was shown. Incombustibility effect was tested by burning a 150 mm long piece, in which three small pieces of 5 x 10 x 50 mm were connected with epoxy resin adhesive, with a Bunsen burner for 30 seconds. After the completion of burning, the long piece was separated back into three small pieces, and the char length, weight loss and after glow time were tested. The beech composite was expected to become incombustible at 40% polymer loading. The vinyl monomer solution of chlorinated aryl chloride oligomer can be easily hardened by electron beam irradiation. Addition of crosslinking agent such as trimethylol propane trimethracrylate prevents the dissolution of hardened methyl acrylate and methyl methacrylate by acetone. The electron beam hardening of aryl resin compound is possible, using benzen peroxide as a catalyst. Floor material can be produced by this process from low density, low price wood. (Iwakiri, K.)

On the regime transitions during the formation of an atmospheric pressure dielectric barrier glow discharge

International Nuclear Information System (INIS)

Martens, T; Bogaerts, A; Brok, W J M; Van Dijk, J

2009-01-01

The atmospheric pressure dielectric barrier discharge in helium is a pulsed discharge in nature. If during the electrical current pulse a glow discharge is reached, then this pulse will last only a few microseconds in operating periods of sinusoidal voltage with lengths of about 10 to 100 μs. In this paper we demonstrate that right before a glow discharge is reached, the discharge very closely resembles the commonly assumed Townsend discharge structure, but actually contains some significant differing features and hence should not be considered as a Townsend discharge. In order to clarify this, we present calculation results of high time and space resolution of the pulse formation. The results indicate that indeed a maximum of ionization is formed at the anode, but that the level of ionization remains high and that the electric field at that time is significantly disturbed. Our results also show where this intermediate structure comes from. (fast track communication)

Atmospheric-pressure solution-cathode glow discharge: A versatile ion source for atomic and molecular mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Schwartz, Andrew J. [Department of Chemistry, Indiana University, Bloomington, IN, 47405 (United States); Williams, Kelsey L. [Department of Chemistry and Biochemistry, Kent State University, Kent, OH, 44242 (United States); Hieftje, Gary M. [Department of Chemistry, Indiana University, Bloomington, IN, 47405 (United States); Shelley, Jacob T., E-mail: shellj@rpi.edu [Department of Chemistry and Biochemistry, Kent State University, Kent, OH, 44242 (United States); Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY, 12180 (United States)

2017-01-15

An atmospheric-pressure solution-cathode glow discharge (SCGD) has been evaluated as an ion source for atomic, molecular, and ambient desorption/ionization mass spectrometry. The SCGD consists of a direct-current plasma, supported in the ambient air in the absence of gas flows, and sustained upon the surface of a flowing liquid cathode. Analytes introduced in the flowing liquid, as an ambient gas, or as a solid held near the plasma are vaporized and ionized by interactions within or near the discharge. Introduction of acidic solutions containing metal salts produced bare elemental ions as well as H{sub 2}O, OH{sup −} and NO{sub 3}{sup −} adducts. Detection limits for these elemental species ranged from 0.1 to 4 ppb, working curves spanned more than 4 orders of linear dynamic range, and precision varied between 5 and 16% relative standard deviation. Small organic molecules were also efficiently ionized from solution, and both the intact molecular ion and fragments were observed in the resulting SCGD mass spectra. Fragmentation of molecular species was found to be tunable; high discharge currents led to harder ionization, while low discharge currents produced stronger molecular-ion signals. Ambient gases and solids, desorbed by the plasma from a glass probe, were also readily ionized by the SCGD. Indeed, strong analyte signals were obtained from solid samples placed at least 2 cm from the plasma. These findings indicate that the SCGD might be useful also for ambient desorption/ionization mass spectrometry. Combined with earlier results that showed the SCGD is useful for ionization of labile biomolecules, the results here indicate that the SCGD is a highly versatile ion source capable of providing both elemental and molecular mass-spectral information. - Highlights: • Solution-cathode glow discharge used as an ionization source for mass spectrometry. • SCGD-MS can provide atomic as well as intact molecular mass spectra. • Atomic limits of detection range

Development of realtime monitoring technology for laser photoreaction product - Development of glow discharge-mass spectrometry (GD-MS) hybrid techniques for trace analysis of refractory elements

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang Chun [Kyungnam University, Masan (Korea); Kim, Ha Suck [Seoul National University, Seoul (Korea); Kim, Hyo Jin [Dongduk Women' s University, Seoul (Korea)

2000-04-01

This research is focusing on development of hybrid techniques of glow discharge-mass spectrometry for the trace analysis of refractory elements. At first, we developed a glow discharge(GD) ionization cell and its characteristics was investigated. The new GD cell was designed based on direct current hollow cathode glow discharge and it is used for quadrupole mass analyzer and time-of-flight mass analyzer. Currently, GD-quadrupole mass spectrometry is working for the analysis of refractory elements. The experimental results show relatively good for trace analysis. In addition, ion mobile spectrometry using plasma and liquid discharge technique were investigated for the analysis of refractory elements and both techniques need more investigation to deduce the their usefulness. 30 refs., 67 figs., 4 tabs. (Author)

Effect of volume and surface charges on discharge structure of glow dielectric barrier discharge

Energy Technology Data Exchange (ETDEWEB)

Xu, Shao-Wei; He, Feng; Wang, Yu; Li, Lulu; Ouyang, Ji-Ting [School of Physics, Beijing Institute of Technology, Beijing 100081 (China)

2013-08-15

The effect of volume and surface charges on the structure of glow dielectric barrier discharge (DBD) has been investigated numerically by using two-dimensional (2D) fluid modeling. The local increase of volume or surface charges induces a kind of activation-inhibition effect, which enhances the local volume discharge and inhibits the discharge in neighborhoods, resulting in non-uniform discharge. The activation-inhibition effect due to the non-uniform volume and/or surface charges depends on the non-uniformity itself and the applied voltage. The activation-inhibition of non-uniform charges has different effects on the volume charges and the accumulated surface charges. The distribution of remaining free charges (seed electrons) in volume at the beginning of voltage pulse plays a key role for the glow DBD structure, resulting in a patterned DBD, when the seed electrons are non-uniform at higher frequency and moderate voltage or uniform DBD, when the seed electrons are uniform at lower frequency or high voltage. The distribution of surface charges is not the determining factor but a result of the formed DBD structure.

Re-design of ITER Glow Discharge Cleaning system based on a fixed electrode concept

International Nuclear Information System (INIS)

Yang, Y.; Maruyama, S.; Kiss, G.; O’Connor, M.; Zhang, Y.; Pitts, R.A.; Shimada, M.; Fang, T.; Wang, Y.; Wang, M.; Pan, Y.; Li, B.; Li, L.

2014-01-01

Highlights: •This paper summarizes the approved new design of ITER GDC. •It is based on the fixed electrode design instead of the previous movable concept. •Estimates were made on the glow current density. •R and D topics on initiation, steady state and heat load were presented. •Other relevant considerations were listed in an exhaustive manner. -- Abstract: A new design of ITER Glow Discharge Cleaning (GDC) system based on a fixed electrode concept replaces the previous design which was based on a movable electrode integrated with the ITER In-Vessel-Viewing-System. Recently the conceptual design of the GDC system was reviewed successfully on the functions, safety, operation and maintenance. The design proposed was checked against the requirements and found to be feasible. This paper gives an overall description of the requirements from physics and operation viewpoints and introduces the design at the conceptual level. Main R and D activities are listed and summarized. Further detailed studies are to be performed in the following design stage

Beam-helicity associated electroproduction of real photons ep {yields} e{gamma}{pi}N in the {Delta}-resonance region

Energy Technology Data Exchange (ETDEWEB)

Airapetian, A. [Giessen Univ. (Germany). 2. Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Akopov, N. [Yerevan Physics Institute (Argentina); Aschenauer, E.C. [DESY Zeuthen (Germany)] [and others; Collaboration: HERMES Collaboration

2013-10-15

The beam-helicity asymmetry in associated electroproduction of real photons, ep {yields} e{gamma}{pi}N, in the {Delta}(1232)-resonance region is measured using the longitudinally polarized HERA positron beam and an unpolarized hydrogen target. Azimuthal Fourier amplitudes of this asymmetry are extracted separately for two channels, ep {yields} e{gamma}{pi}{sup 0}p and ep {yields} e{gamma}{pi}{sup +}n, from a data set collected with a recoil detector. All asymmetry amplitudes are found to be consistent with zero.

Intense low energy positron beams

International Nuclear Information System (INIS)

Lynn, K.G.; Jacobsen, F.M.

1993-01-01

Intense positron beams are under development or being considered at several laboratories. Already today a few accelerator based high intensity, low brightness e + beams exist producing of the order of 10 8 - 10 9 e + /sec. Several laboratories are aiming at high intensity, high brightness e + beams with intensities greater than 10 9 e + /sec and current densities of the order of 10 13 - 10 14 e + sec - 1 cm -2 . Intense e + beams can be realized in two ways (or in a combination thereof) either through a development of more efficient B + moderators or by increasing the available activity of B + particles. In this review we shall mainly concentrate on the latter approach. In atomic physics the main trust for these developments is to be able to measure differential and high energy cross-sections in e + collisions with atoms and molecules. Within solid state physics high intensity, high brightness e + beams are in demand in areas such as the re-emission e + microscope, two dimensional angular correlation of annihilation radiation, low energy e + diffraction and other fields. Intense e + beams are also important for the development of positronium beams, as well as exotic experiments such as Bose condensation and Ps liquid studies

Techniques for evaluation of E-beam evaporative processes

International Nuclear Information System (INIS)

Meier, T.C.; Nelson, C.M.

1996-01-01

High dynamic range video imaging of the molten pool surface has provided insight regarding process responses at the melt pool liquid-vapor interface. A water-cooled video camera provides continuous high resolution imaging of the pool surface from a low angle position within 20 cm of the liquid-vapor interface. From the vantage point, the e-beam footprint is clearly defined and melt pool free surface shape can be observed. Effects of changes in a beam footprint, power distribution, and sweep frequency on pool surface shape and stability of vaporization are immediately shown. Other events observed and recorded include: formation of the pool and dissipation of ''rafts'' on the pool surface during startup, behavior of feed material as it enters the pool, effects of feed configuration changes on mixing of feed entering the pool volume and behaviors of co-evaporated materials of different vapor pressures at the feed/pool boundary. When used in conjunction with laser vapor monitoring, correlation between pool surface phenomena and vaporizer performance has been identified. This video capability was used in verifying the titanium evaporation model results presented at this conference by confirming the calculated melt pool surface deformations caused by vapor pressure of the departing evaporant at the liquid-vapor interface

Techniques for evaluation of E-beam evaporative processes

Energy Technology Data Exchange (ETDEWEB)

Meier, T.C.; Nelson, C.M.

1996-10-01

High dynamic range video imaging of the molten pool surface has provided insight regarding process responses at the melt pool liquid-vapor interface. A water-cooled video camera provides continuous high resolution imaging of the pool surface from a low angle position within 20 cm of the liquid-vapor interface. From the vantage point, the e-beam footprint is clearly defined and melt pool free surface shape can be observed. Effects of changes in a beam footprint, power distribution, and sweep frequency on pool surface shape and stability of vaporization are immediately shown. Other events observed and recorded include: formation of the pool and dissipation of ``rafts`` on the pool surface during startup, behavior of feed material as it enters the pool, effects of feed configuration changes on mixing of feed entering the pool volume and behaviors of co-evaporated materials of different vapor pressures at the feed/pool boundary. When used in conjunction with laser vapor monitoring, correlation between pool surface phenomena and vaporizer performance has been identified. This video capability was used in verifying the titanium evaporation model results presented at this conference by confirming the calculated melt pool surface deformations caused by vapor pressure of the departing evaporant at the liquid-vapor interface.

Peculiarities of glow modes of argon atmospheric pressure radio-frequency capacitive discharge with isolated electrodes

International Nuclear Information System (INIS)

Bazhenov, V.Yu.; Tsiolko, V.V.; Piun, V.M.; Chaplinskiy, R.Yu.; Kuzmichev, A.I.

2013-01-01

Glow characteristics of capacitive radio frequency discharge with isolated electrodes in low-current α and highcurrent gamma modes are determined experimentally. It is shown that transition from α mode to gamma mode occurs through a phase of coexistence of both modes in different parts of the discharge gap.

Hardening of alloys in glow discharge with the use of pulsed electric current

International Nuclear Information System (INIS)

Shipko, M.N.; Pomel'nikova, A.S.; Solunin, A.M.; Solunin, M.A.

2002-01-01

The effect of ex/ternal pulsed electric field on the thickness of a hardened surface layer of a Nd-Fe-B system alloy during chemical heat treatment in a glow discharge is studied. The relationship is established between the hardened layer thickness and the frequency of external electric field which is verified by derived equations for the relation between electron energy and pulsed electric field frequency [ru

Beam-based alignment and tuning procedures for e+e- collider final focus systems

International Nuclear Information System (INIS)

Bulos, F.; Burke, D.; Helm, R.; Irwin, J.; Odian, A.; Roy, G.; Ruth, R.; Yamamoto

1991-01-01

For future linear colliders, with very small emittances and beam sizes and demanding tolerances on final focus system alignment and magnet errors, it becomes increasingly important to use the beam as a diagnostic tool. The authors report here procedures they have identified and will be implemented in the Final Focus Test Beam at SLAC incorporating (1) quadrupole strength changes, (2) central orbit modifications, (3) spot size measurements, and (4) beam stability monitoring

SU-E-T-464: On the Equivalence of the Quality Correction Factor for Pencil Beam Scanning Proton Therapy

International Nuclear Information System (INIS)

Sorriaux, J; Paganetti, H; Testa, M; Giantsoudi, D; Schuemann, J; Bertrand, D; Orban de Xivry, J.; Lee, J; Palmans, H; Vynckier, S; Sterpin, E

2014-01-01

Purpose: In current practice, most proton therapy centers apply IAEA TRS-398 reference dosimetry protocol. Quality correction factors (kQ) take into account in the dose determination process the differences in beam qualities used for calibration unit and for treatment unit. These quality correction factors are valid for specific reference conditions. TRS-398 reference conditions should be achievable in both scattered proton beams (i.e. DS) and scanned proton beams (i.e. PBS). However, it is not a priori clear if TRS-398 kQ data, which are based on Monte Carlo (MC) calculations in scattered beams, can be used for scanned beams. Using TOPAS-Geant4 MC simulations, the study aims to determine whether broad beam quality correction factors calculated in TRS-398 can be directly applied to PBS delivery modality. Methods: As reference conditions, we consider a 10×10×10 cm 3 homogeneous dose distribution delivered by PBS system in a water phantom (32/10 cm range/modulation) and an air cavity placed at the center of the spread-out-Bragg-peak. In order to isolate beam differences, a hypothetical broad beam is simulated. This hypothetical beam reproduces exactly the same range modulation, and uses the same energy layers than the PBS field. Ion chamber responses are computed for the PBS and hypothetical beams and then compared. Results: For an air cavity of 2×2×0.2 cm 3 , the ratio of ion chamber responses for the PBS and hypothetical beam qualities is 0.9991 ± 0.0016. Conclusion: Quality correction factors are insensitive to the delivery pattern of the beam (broad beam or PBS), as long as similar dose distributions are achieved. This investigation, for an air cavity, suggests that broad beam quality correction factors published in TRS-398 can be applied for scanned beams. J. Sorriaux is financially supported by a public-private partnership involving the company Ion Beam Applications (IBA)

Beam-beam interaction working group summary

International Nuclear Information System (INIS)

Siemann, R.H.

1995-01-01

The limit in hadron colliders is understood phenomenologically. The beam-beam interaction produces nonlinear resonances and makes the transverse tunes amplitude dependent. Tune spreads result from the latter, and as long as these tune spreads do not overlap low order resonances, the lifetime and performance is acceptable. Experience is that tenth and sometimes twelfth order resonances must be avoided, and the hadron collider limit corresponds roughly to the space available between resonances of that and lower order when operating near the coupling resonance. The beam-beam interaction in e + e - colliders is not understood well. This affects the performance of existing colliders and could lead to surprises in new ones. For example. a substantial amount of operator tuning is usually required to reach the performance limit given above, and this tuning has to be repeated after each major shutdown. The usual interpretation is that colliding beam performance is sensitive to small lattice errors, and these are being reduced during tuning. It is natural to ask what these errors are, how can a lattice be characterized to minimize tuning time, and what aspects of a lattice should receive particular attention when a new collider is being designed. The answers to this type of question are not known, and developing ideas for calculations, simulations and experiments that could illuminate the details of the beam-beam interaction was the primary working group activity

Analysis of the different zones of glow discharge of ethyl alcohol (C2H6O)

International Nuclear Information System (INIS)

Torres, C; Reyes, P G; Mulia, J; Castillo, F; Martínez, H

2014-01-01

The aim of this work is to explore the emission spectroscopy of ethyl alcohol in some regions, also is determine the result elements of the glow discharge, the spectrums were observed in a range of 200 at 1100 nm in the different zones inside of the tube at different distances of 20 and 30 cm. The elements are: in anode region C 6 H 5 (483.02 nm), CHO (519.56 nm) and H 2 (560.47 nm), in the positive column CO 2 + (315.52 y 337.00 nm), O + (357.48 nm), CH + (380.61 nm) and CO + (399.73 nm); in the cathode region we observed O + (391.19 nm), CHOCHO (428.00 nm), CO + (471.12 nm) and H 2 (656.52 nm). C 6 H 5 , CHO y H 2 species occurring in all regions analyzed varying the glow discharge emission intensity.

Beam-based alignment and tuning procedures for e+e- collider final focus systems

International Nuclear Information System (INIS)

Bulos, F.; Burke, D.; Helm, R.; Irwin, J.; Odian, A.; Roy, G.; Ruth, R.; Yamamoto, N.

1991-05-01

For future linear colliders, with very small emittances and beam sizes and demanding tolerances on final focus system alignment and magnet errors, it becomes increasingly important to use the beam as a diagnostic tool. We report here procedures we have identified and will be implemented in the Final Focus Test Beam at SLAC incorporating (1) quadrupole strength changes, (2) central orbit modifications, (3) spot size measurements, and (4) beam stability monitoring. 3 refs., 4 figs., 3 tabs

A kinetic model for low pressure glow discharges in the presence of dust particles

International Nuclear Information System (INIS)

Wang Dezhen; Dong, J.Q.; Mahajan, S.M.

1996-05-01

A kinetic model for electrons in dusty plasmas is developed. The Boltzmann and the dust charging balance equations are solved self-consistently. The dependence of the dust particle surface potential on plasma parameters and the effects of particulate contamination on electron energy distribution are investigated for direct-current argon glow discharges. It is shown that the dust particle surface potential obtained from this model is higher than that obtained for a Maxwellian electron distribution, and that the higher energy portion of the electron distribution is reduced in the presence of dust particles. Electron-dust collection and electron-atom inelastic collision are the main electron energy loss processes, and the electron energy loss due to electron-dust elastic collision is negligibly small for 10 -16 V cm 2 -15 V cm 2 under the discharge conditions considered in this work, where E is the externally applied electric field and N is the argon atom density. (author). 16 refs, 8 figs

Probiotic Bacteria Induce a ‘Glow of Health’

Science.gov (United States)

Smillie, Christopher; Varian, Bernard J.; Ibrahim, Yassin M.; Lakritz, Jessica R.; Alm, Eric J.; Erdman, Susan E.

2013-01-01

Radiant skin and hair are universally recognized as indications of good health. However, this ‘glow of health’ display remains poorly understood. We found that feeding of probiotic bacteria to aged mice induced integumentary changes mimicking peak health and reproductive fitness characteristic of much younger animals. Eating probiotic yogurt triggered epithelial follicular anagen-phase shift with sebocytogenesis resulting in thick lustrous fur due to a bacteria-triggered interleukin-10-dependent mechanism. Aged male animals eating probiotics exhibited increased subcuticular folliculogenesis, when compared with matched controls, yielding luxuriant fur only in probiotic-fed subjects. Female animals displayed probiotic-induced hyperacidity coinciding with shinier hair, a feature that also aligns with fertility in human females. Together these data provide insights into mammalian evolution and novel strategies for integumentary health. PMID:23342023

High-Energy Radiation from Thunderstorms with ADELE: TGFs, Steps, and Glows

Science.gov (United States)

Smith, David M.; Kelley, Nicole; Martinez-McKinney, Forest; Zhang, Zi Yan; Hazelton, Bryna; Grefenstette, Brian; Splitt, Michael; Lazarus, Steven; Ulrich, William; Levine, Steven;

Visualizing ignition and combustion of methanol mixtures in a diesel engine; Methanol funmu no glow chakka to nensho no kashika

Energy Technology Data Exchange (ETDEWEB)

Inomoto, Y; Harada, T; Kusaka, J; Daisho, Y; Kihara, R; Saito, T [Waseda University, Tokyo (Japan)

1997-10-01

A glow-assisted ignition system tends to suffer from poor ignitability and slow flame propagation at low load in a direct-injection diesel engine fueled with methanol. To investigate the ignition process and improve such disadvantages, methanol sprays, their ignition and flames were visualized at high pressures and temperatures using a modified two-stroke engine. The results show that parameters influencing ignition, the location of a glow-plug, swirl level, pressure and temperature are important. In addition, a full kinetics calculation was conducted to predict the delay of methanol mixture ignition by taking into account 39 chemical species and 157 elementary reactions. 3 refs., 9 figs.

Accelerators for E-beam and X-ray processing

Energy Technology Data Exchange (ETDEWEB)

Auslender, V.L. E-mail: auslen@inp.nsk.su; Bryazgin, A.A.; Faktorovich, B.L.; Gorbunov, V.A.; Kokin, E.N.; Korobeinikov, M.V.; Krainov, G.S.; Lukin, A.N.; Maximov, S.A.; Nekhaev, V.E.; Panfilov, A.D.; Radchenko, V.N.; Tkachenko, V.O.; Tuvik, A.A.; Voronin, L.A

2002-03-01

During last years the demand for pasteurization and desinsection of various food products (meat, chicken, sea products, vegetables, fruits, etc.) had increased. The treatment of these products in industrial scale requires the usage of powerful electron accelerators with energy 5-10 MeV and beam power at least 50 kW or more. The report describes the ILU accelerators with energy range up to 10 MeV and beam power up to 150 kW.The different irradiation schemes in electron beam and X-ray modes for various products are described. The design of the X-ray converter and 90 deg. beam bending system are also given.

Effect of F- and Z2-light illumination on thermal glow curves of pretreated NaCl:Ca phosphors

International Nuclear Information System (INIS)

Joshi, R.V.; Dhake, K.P.; Joshi, T.R.

1985-01-01

It is known that colour centres are produced when doped or undoped alkali halides are exposed to ionizing radiation. Earlier work has also revealed an intimate relationship between the thermoluminescence (TL) centres associated with the glow peaks and different species of colour centres. The aim of the present investigation has been to find out the species of colour centres associated with the observed thermal glow peaks. The measurements were carried out on thermally treated Ca-doped NaCl phosphors. The thermal treatment involves annealing of the phosphors at 550 C. The specimens were irradiated by a 90 Sr 20 mCi source. A figure showing the glow curves recorded immediately after β-irradiation, after β-irradiation followed by F-light illumination and after β-irradiation followed by 20 min decay at room temperature. The F-light illumination leads to the quenching of the peak at 137 C and generates new peaks at 113 and 157 C. The bleaching effect becomes more significant with the increase in the duration of F-light illumination. The effect of F-light illumination followed by Z 2 -light illumination shows that of the two peaks appearing earlier, the 113 C peak is selectively suppressed. The isothermal bleaching at room temperature for 20 min does not affect the intensity of the 137 C peak. The results are discussed. (author)

E-beam crosslinked, biocompatible functional hydrogels incorporating polyaniline nanoparticles

International Nuclear Information System (INIS)

Dispenza, C.; Sabatino, M.-A.; Niconov, A.; Chmielewska, D.; Spadaro, G.

2012-01-01

PANI aqueous nanocolloids in their acid-doped, inherently conductive form were synthesised by means of suitable water soluble polymers used as stabilisers. In particular, poly(vinyl alcohol) (PVA) or chitosan (CT) was used to stabilise PANI nanoparticles, thus preventing PANI precipitation during synthesis and upon storage. Subsequently, e-beam irradiation of the PANI dispersions has been performed with a 12 MeV Linac accelerator. PVA-PANI nanocolloid has been transformed into a PVA-PANI hydrogel nanocomposite by radiation induced crosslinking of PVA. CT-PANI nanoparticles dispersion, in turn, was added to PVA to obtain wall-to-wall gels, as chitosan mainly undergoes chain scission under the chosen irradiation conditions. While the obtainment of uniform PANI particle size distribution was preliminarily ascertained with laser light scattering and TEM microscopy, the typical porous structure of PVA-based freeze dried hydrogels was observed with SEM microscopy for the hydrogel nanocomposites. UV−visible absorption spectroscopy demonstrates that the characteristic, pH-dependent and reversible optical absorption properties of PANI are conferred to the otherwise optically transparent PVA hydrogels. Selected formulations have been also subjected to MTT assays to prove the absence of cytotoxicity. - Highlights: ► PANI nanocolloids were chemically synthesised in the presence of PVA and chitosan. ► PANI dispersions were transformed into hydrogel nanocomposites by e-beam irradiation. ► Characteristic optical properties of PANI were shown by the nanocomposite hydrogels. ► Absence of cytotoxicity for the nanocomposite hydrogels is demonstrated. ► Results encourage developments for application in biosensing and smart drug delivery.

Sustainable and ICT-Enabled Development in Developing Areas: An E-Heritage E-Commerce Service for Handicraft Marketing

Science.gov (United States)

Muhammad, Tufail; Kim, Kwan Myung

2018-04-01

Human-induced threats serve as potential hazards to cultural heritage assets, especially in developing areas where the local community, in general, is a deprived class. Sustainable tourism development is acknowledged as an economic activity to ensure careful management of assets along with local community empowerment and participation. As such, ICT-enabled development is applied in rural development projects to promote sustainable rural livelihood, but success is still limited due to a lack of community involvement and sharing in the economic gains of tourism. With this perspective in mind, the present study focuses on emerging marketing models (e-commerce) that can provide new business ventures for local communities by identifying critical online marketing elements driven by local residents.

Studies of reaction difference between γ-ray and glow discharge on hydrogenation of unsaturated fatty acid esters

International Nuclear Information System (INIS)

Sakoda, Tatsuya; Nieda, Hiroshi; Kitahara, Kazuta; Ando, Kiyomi

2000-01-01

Hydrogenation of unsaturated fatty acid esters using an inductively coupled plasma at low pressure was performed, and electron temperature and density were measured using a double-probe in order to investigate the reaction difference between γ-ray and glow discharge on hydrogenation. In this experiment, unsaturated fatty acid esters were partly hydrogenated by the hydrogen plasma that had electron temperature of 3.5 eV, which was more efficient than γ-ray irradiation method. As a result, it was found that the plasma can effectively supply electrons that had the optimum energy for hydrogenation at the interface of fatty acids as well as excited atoms and ions. Also, the plasma generated at low pressure would be possible to convert unsaturated fatty acids into saturated fatty acids without breaking the starting monomer. (author)

Beam structure and transverse emittance studies of high-energy ion beams

International Nuclear Information System (INIS)

Saadatmand, K.; Johnson, K.F.; Schneider, J.D.

1991-01-01

A visual diagnostic technique has been developed to monitor and study ion beam structure shape and size along a transport line. In this technique, a commercially available fluorescent screen is utilized in conjunction with a video camera. This visual representation of the beam structure is digitized and enhanced through use of false-color coding and displayed on a TV monitor for on-line viewing. Digitized information is stored for further off-line processing (e.g., extraction of beam profiles). An optional wire grid placed upstream of the fluor screen adds the capability of transverse emittance (or angular spread) measurement to this technique. This diagnostic allows real-time observation of the beam response to parameter changes (e.g., evolution of the beam structure, shifts in the beam intensity at various spatial locations within the beam perimeter, and shifts in the beam center and position). 3 refs., 5 figs

Individual and Social Requirement Aspects of Sustainable eLearning Systems

OpenAIRE

Alharthi, Ahmed D.; Spichkova, Maria

2017-01-01

Internationalization of the higher education has created the so-called borderless university, which provides better opportunities for learning and increases the human and social sustainability. eLearning systems are a special kind of software systems, developed to provide a platform for accessible teaching and learning, including also online access to learning materials and online support for learning and teaching. The aim of our current work is to extract, analyse, and combine the results fr...

Analysis of read-out heating rate effects on the glow peaks of TLD-100 using WinGCF software

Energy Technology Data Exchange (ETDEWEB)

Bauk, Sabar, E-mail: sabar@usm.my [Physics Section, School of Distance Education, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Hussin, Siti Fatimah [School of Physics, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Alam, Md. Shah [Physics Section, School of Distance Education, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Physics Department, Shahjalal University of Science and Technology, Sylhet (Bangladesh)

2016-01-22

This study was done to analyze the effects of the read-out heating rate on the LiF:Mg,Ti (TLD-100) thermoluminescent dosimeters (TLD) glow peaks using WinGCF computer software. The TLDs were exposed to X-ray photons with a potential difference of 72 kVp and 200 mAs in air and were read-out using a Harshaw 3500 TLD reader. The TLDs were read-out using four read-out heating rates at 10, 7, 4 and 1 °C s{sup −1}. It was observed that lowering the heating rate could separate more glow peaks. The activation energy for peak 5 was found to be lower than that for peak 4. The peak maximum temperature and the integral value of the main peak decreased as the heating rate decreases.

Evolution of the Tl glow curve of Zn S:Mn nanocrystalline; Evolucion de la curva de brillo Tl de ZnS:Mn nanocristalino

Energy Technology Data Exchange (ETDEWEB)

Ortiz H, A. A. [Universidad Autonoma de San Luis Potosi, Doctorado en Ingenieria y Ciencia de Materiales, 78000 San Luis Potosi (Mexico); Mendez G, V. H. [Universidad Autonoma de San Luis Potosi, Coordinacion para la Innovacion y Aplicacion de la Ciencia y la Tecnologia, 78000 San Luis Potosi (Mexico); Perez A, M. L.; Ortega S, J. J.; Araiza, J. J. [Universidad Autonoma de Zacatecas, Unidad Academica de Fisica, 98000, Zacatecas, Zac. (Mexico); Rivera, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Alfaro C, M. R. [Centro de Investigacion en Materiales Avanzados, Alianza Norte 202, 66600 Apodaca, Nuevo Leon (Mexico); Vega C, H. R., E-mail: icearturoortiz@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, 98068 Zacatecas, Zac. (Mexico)

2015-10-15

Full text: In the last two decades, the search for new materials for dosimetry has included semiconductor nano materials because of their luminescent properties. This search has included the study, synthesis, characterization and performance of nano structured semiconductors, which optoelectronic properties determine their applications. In this paper the evolution of the thermoluminescent glow curve of nanocrystalline powder samples (40-70 nm) of zinc sulfide doped with manganese (Zn S:Mn) was analyzed at a dose of 500 Gy using a {sup 60}Co source. This material was synthesized by the coprecipitation method and heat treated at 500 degrees C in forming gas atmosphere (80 N{sub 2}:20H{sub 2}). Photoluminescence results indicate a direct relationship between the concentration of manganese and the intensity of a peak at λ ≅ 600 nm. By means of numerical deconvolution the behavior of the glow curves obtained at different times after exposure was analyzed. The causing traps of thermoluminescence are to 0.60 ± 0.05 and 1.7 ± 0.4 eV below the conduction band and within the band gap. The fading and a variation in the shape of the brightness curve (evolution) caused by non radiative transitions (rotational and vibrational) within the crystal structure of the material is also reported. (Author)

A research of possibility for negative muon production by a low energy electron beam accompanying ion beam

International Nuclear Information System (INIS)

Uramoto, Joshin.

1993-12-01

A low energy electron beam (≤ 2000 eV) is injected perpendicularly to a uniform magnetic field, together with a low energy positive ion beam. On this magnetic mass analysis (using the uniform magnetic field), a peak of secondary electron current to the beam collector (arranging as a mass analyzer of 90deg type), appears at an analyzing magnetic field which corresponds exactly to a relation of negative muon μ - (the mass m=207 m e and the charge q=e, where m e and e are mass and charge of electron). The ion beam is essential for the peak appearance, which is produced by decelerating electrically the electron beam in front of the entrance slit of the mass analyzer, and by introducing a neutral gas into the electron beam region and producing a plasma through the ionization. We consider that a very small amount of negative muons may be produced through local cyclotron motions of the injected beam electrons in the ion beam or by an interaction between the bunched beam electrons and beam ions. (author)

Secondary electron emission and glow discharge properties of 12CaO·7Al2O3 electride for fluorescent lamp applications

International Nuclear Information System (INIS)

Watanabe, Satoru; Watanabe, Toshinari; Ito, Kazuhiro; Miyakawa, Naomichi; Ito, Setsuro; Hosono, Hideo; Mikoshiba, Shigeo

2011-01-01

12CaO·7Al 2 O 3 electride, a sub-nanoporous compound having a work function of 2.4 eV, was examined as a candidate cathode material in fluorescent lamps. The electron emission yield was higher and the discharge voltage was lower for 12CaO·7Al 2 O 3 than for existing cathode materials such as Ni, Mo or W; therefore, the energy consumption of the fluorescent lamps can be improved using 12CaO·7Al 2 O 3 cathodes. Prototype glow-discharge lamps using 12CaO·7Al 2 O 3 were constructed and exhibited reasonable durability.

Secondary electron emission and glow discharge properties of 12CaO·7Al2O3 electride for fluorescent lamp applications.

Science.gov (United States)

Watanabe, Satoru; Watanabe, Toshinari; Ito, Kazuhiro; Miyakawa, Naomichi; Ito, Setsuro; Hosono, Hideo; Mikoshiba, Shigeo

2011-06-01

12CaO·7Al 2 O 3 electride, a sub-nanoporous compound having a work function of 2.4 eV, was examined as a candidate cathode material in fluorescent lamps. The electron emission yield was higher and the discharge voltage was lower for 12CaO·7Al 2 O 3 than for existing cathode materials such as Ni, Mo or W; therefore, the energy consumption of the fluorescent lamps can be improved using 12CaO·7Al 2 O 3 cathodes. Prototype glow-discharge lamps using 12CaO·7Al 2 O 3 were constructed and exhibited reasonable durability.

Secondary electron emission and glow discharge properties of 12CaOcenterdot7Al2O3 electride for fluorescent lamp applications

Directory of Open Access Journals (Sweden)

Satoru Watanabe, Toshinari Watanabe, Kazuhiro Ito, Naomichi Miyakawa, Setsuro Ito, Hideo Hosono and Shigeo Mikoshiba

2011-01-01

Full Text Available 12CaOcenterdot7Al2O3 electride, a sub-nanoporous compound having a work function of 2.4 eV, was examined as a candidate cathode material in fluorescent lamps. The electron emission yield was higher and the discharge voltage was lower for 12CaOcenterdot7Al2O3 than for existing cathode materials such as Ni, Mo or W; therefore, the energy consumption of the fluorescent lamps can be improved using 12CaOcenterdot7Al2O3 cathodes. Prototype glow-discharge lamps using 12CaOcenterdot7Al2O3 were constructed and exhibited reasonable durability.

The quest for μ → eγ and its experimental limiting factors at future high intensity muon beams

Energy Technology Data Exchange (ETDEWEB)

Cavoto, G. [' ' Sapienza' ' Univ., Roma (Italy). Dipt. di Fisica; Istituto Nazionale di Fisica Nucleare, Rome (Italy); Papa, A. [Paul Scherrer Institut, Villigen (Switzerland); Renga, F.; Voena, C. [Istituto Nazionale di Fisica Nucleare, Rome (Italy); Ripiccini, E. [Geneve Univ. (Switzerland). Dept. de Physique Nucleaire et Corpusculaire

2018-01-15

The search for the lepton flavor violating decay μ{sup +} → e{sup +}γ will reach an unprecedented level of sensitivity within the next five years thanks to the MEG-II experiment. This experiment will take data at the Paul Scherrer Institut where continuous muon beams are delivered at a rate of about 10{sup 8} muons per second. On the same time scale, accelerator upgrades are expected in various facilities, making it feasible to have continuous beams with an intensity of 10{sup 9} or even 10{sup 10} muons per second. We investigate the experimental limiting factors that will define the ultimate performances, and hence the sensitivity, in the search for μ{sup +} → e{sup +}γ with a continuous beam at these extremely high rates. We then consider some conceptual detector designs and evaluate the corresponding sensitivity as a function of the beam intensity. (orig.)

Dynamic model based on voltage transfer curve for pattern formation in dielectric barrier glow discharge

Energy Technology Data Exchange (ETDEWEB)

Li, Ben; He, Feng; Ouyang, Jiting, E-mail: jtouyang@bit.edu.cn [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Duan, Xiaoxi [Research Center of Laser Fusion, CAEP, Mianyang 621900 (China)

2015-12-15

Simulation work is very important for understanding the formation of self-organized discharge patterns. Previous works have witnessed different models derived from other systems for simulation of discharge pattern, but most of these models are complicated and time-consuming. In this paper, we introduce a convenient phenomenological dynamic model based on the basic dynamic process of glow discharge and the voltage transfer curve (VTC) to study the dielectric barrier glow discharge (DBGD) pattern. VTC is an important characteristic of DBGD, which plots the change of wall voltage after a discharge as a function of the initial total gap voltage. In the modeling, the combined effect of the discharge conditions is included in VTC, and the activation-inhibition effect is expressed by a spatial interaction term. Besides, the model reduces the dimensionality of the system by just considering the integration effect of current flow. All these greatly facilitate the construction of this model. Numerical simulations turn out to be in good accordance with our previous fluid modeling and experimental result.

Glow discharge lamp: a light source for optical emission spectroscopy

International Nuclear Information System (INIS)

Vishwanathan, K.S.; Srinivasan, V.; Nalini, S.; Mahalingam, T.R.

1990-01-01

A glow discharge lamp based on a modified version of the Grimm design has been fabricated. Its utility as a radiation source for optical emmission spectrography by standardising a method for the analysis of low alloy steels using a set of certified standards from DMRL, Hyderabad, has been demonstrated. A model has been proposed where the sputtering rates of different metals have been correlated with their heats of sublimation, metallic radii and densities. Sputtering rates of ten different metals obtained from literature have been used to test this model, and the correlation appears to be excellent. (author). 19 re fs., 13 figs., 2 tabs

Experimental study of spatial distribution of Ar glow discharge plasma

International Nuclear Information System (INIS)

Guo, X.M.; Zhou, T.D.; Pai, S.T.

1996-01-01

The characteristics of the spatial distribution of Ar glow discharge plasma were experimentally investigated. By means of direct comparisons between theory and experiment, the effects of the variation of gap separation, gas pressure, and electrode radius on the spatial distributions of electron density and electric field were studied. Results indicate that the maximum electron density moves toward the cathode as the gap separation or gas pressure increases while variation of electrode radius produces little effect. Predictions from a theoretical model have been experimentally verified. General agreements between theory and experiment were found to be reasonably good except in the cathode region, where discrepancy exists. copyright 1996 American Institute of Physics

Mobile e-Commerce Recommendation System Based on Multi-Source Information Fusion for Sustainable e-Business

Directory of Open Access Journals (Sweden)

Yan Guo

2018-01-01

Full Text Available A lack of in-depth excavation of user and resources information has become the main bottleneck restricting the predictive analytics of recommendation systems in mobile commerce. This article provides a method which makes use of multi-source information to analyze consumers’ requirements for e-commerce recommendation systems. Combined with the characteristics of mobile e-commerce, this method employs an improved radial basis function (RBF network in order to determine the weights of recommendations, and an improved Dempster–Shafer theory to fuse the multi-source information. Power-spectrum estimation is then used to handle the fusion results and allow decision-making. The experimental results illustrate that the traditional method is inferior to the proposed approach in terms of recommendation accuracy, simplicity, coverage rate and recall rate. These achievements can further improve recommendation systems, and promote the sustainable development of e-business.

The influence of impurity and particle control on TMX-U [Tandem Mirror Experiment Upgrade] plasma operation

International Nuclear Information System (INIS)

Allen, S.L.; Yu, T.L.; Foote, J.H.; Pickles, W.L.

1985-11-01

A variety of techniques are used in TMX-U to control impurities and reflux: repeated plasma pulses, glow discharge cleaning (GDC), and gettering. A series of experiments under three different plasma-wall conditions was performed: no wall conditioning after a machine maintenance cycle, a glow-discharge-cleaned wall, and a gettered wall. Several plasma diagnostics to determine the effect of these procedures on TMX-U plasma parameters were used. Spectroscopic measurements indicated that GDC reduced impurities and increased the electron temperature, enabling full-duration beam-sustained plasma operation without a large number of repeated plasma pulses. Gettering further reduced the impurities and the neutral pressure, and this improved condition persisted for several shots after gettering was stopped. Measurements from residual gas analyzers and an end-loss ion spectrometer indicated that hydrogen is present in the plasma during the initial deuterium operation after pumpdown; the hydrogen level decreased after plasma operation with gettering, indicating reduced wall recycling

Use of laser-ablated fast particle beams for the measurement of n/sub e/ and T/sub e/ profiles in the TEXTOR boundary layer

International Nuclear Information System (INIS)

Pospieszczyk, A.; Ross, G.G.

1988-01-01

We have developed a source of suprathermal atoms consisting of a laser system, which ablates small portions of coating materials from the rear side of a glass substrate. The coating can be either a single species or a multilayer of several-thousand-angstrom thickness. Neutral particle beams produced by this method can have energies in the range of about 10 eV and penetrate into the plasma up to line densities of about n/sub e/l = 1 x 10 13 cm -2 . For the determination of the electron temperature we have chosen two elements, the ionization and excitation cross sections of which differ in the range up to 100 eV. For TEXTOR a two-component target with a C-LiF coating is used, which delivers a Li and C beam with about 5- and 15-eV energy, respectively, ablated by a ruby laser with 1-J energy. The beam attenuation is determined from the emitted light by using a camera with a Si-diode array system for spatial recording. The different attenuations and emission characteristics then allow the determination of radial electron density and temperature profiles over the spatial range from the liner into a few centimeters beyond the limiter

Measurement of νμ and νe Events in an Off-Axis Horn-Focused Neutrino Beam

International Nuclear Information System (INIS)

Adamson, P.; Brice, S. J.; Brown, B. C.; Choudhary, B. C.; Finley, D. A.; Ford, R.; Garcia, F. G.; Harris, D.; Hylen, J.; Kasper, P.; Kobilarcik, T.; Kourbanis, I.; Marchionni, A.; Marsh, W.; Mills, F.; Moore, C. D.; Prebys, E.; Russell, A. D.; Smart, W.; Spentzouris, P.

2009-01-01

We report the first observation of off-axis neutrino interactions in the MiniBooNE detector from the NuMI beam line at Fermilab. The MiniBooNE detector is located 745 m from the NuMI production target, at 110 mrad angle (6.3 deg.) with respect to the NuMI beam axis. Samples of charged-current quasielastic ν μ and ν e interactions are analyzed and found to be in agreement with expectation. This provides a direct verification of the expected pion and kaon contributions to the neutrino flux and validates the modeling of the NuMI off-axis beam.

Study of beam-beam long range compensation with octupoles

CERN Document Server

AUTHOR|(CDS)2068329; Pieloni, Tatiana; Buffat, Xavier; Tambasco, Claudia

2017-01-01

Long range beam-beam effects are responsible for particle losses and define fundamental operational parameters of colliders (i.e. crossing angles, intensities, emittances, ${\\beta}$${^∗}$). In this study we propose octuple magnets as a possible scheme to efficiently compensate long-range beam-beam interactions with a global correction scheme. The impact and improvements on the dynamic aperture of colliding beams together with estimates of the luminosity potentials are dis- cussed for the HL-LHC upgrade and extrapolations made for the FCC project.

On the exploration of effect of critical beam power on the propagation of Gaussian laser beam in collisionless magnetized plasma

Science.gov (United States)

Urunkar, T. U.; Valkunde, A. T.; Vhanmore, B. D.; Gavade, K. M.; Patil, S. D.; Takale, M. V.

2018-05-01

It is quite known that critical power of the laser plays vital role in the propagation of Gaussian laser beam in collisionless plasma. The nonlinearity in dielectric constant considered herein is due to the ponderomotive force. In the present analysis, the interval of critical beam power has been explored to sustain the competition between diffraction and self-focusing of Gaussian laser beam during propagation in collisionless magnetized plasma. Differential equation for beam-width parameter has been established by using WKB and paraxial approximations under parabolic equation approach. The effect of critical power on the propagation of Gaussian laser beam has been presented graphically and discussed.

High energy electron beams characterization using CaSO{sub 4}:Dy+PTFE Phosphors for clinical therapy applications

Energy Technology Data Exchange (ETDEWEB)

Rivera, T., E-mail: trivera@ipn.mx [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, Col. Irrigacion. 11500 Mexico DF (Mexico); Espinoza, A.; Von, S.M. [Centro Estatal de Cancerologia de los Servicios de Salud de Nayarit, Enfermeria S/n, Fracc, Fray Junipero Serra, 63169 Tepic Nay (Mexico); Alvarez, R.; Jimenez, Y. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, Col. Irrigacion. 11500 Mexico DF (Mexico)

2012-07-15

In the present work high energy electron beam dosimetry from linear accelerator (LINACs) for clinical applications using dysprosium doped calcium sulfate embedded in polytetrafluorethylene (CaSO{sub 4}:Dy+PTFE) was studied. The irradiations were carried out using high electron beams (6 to 18 MeV) from a linear accelerator (LINAC) Varian, CLINAC 2300C/D, for clinical practice purpose. The electron irradiations were obtained using the water solid in order to guarantee electronic equilibrium conditions (EEC). Field shaping for electron beams was obtained with electron cones. Glow curve and other thermoluminescent characteristics of CaSO{sub 4}:Dy+PTFE were conducted under high electrons beams irradiations. The TL response of the pellets showed an intensity peak centered at around 215 Degree-Sign C. TL response of CaSO{sub 4}:Dy+PTFE as a function of high electron absorbed dose showed a linearity in a wide range. To obtain reproducibility characteristic, a set of pellets were exposed repeatedly for the same electron absorbed dose. The results obtained in this study can suggest the applicability of CaSO{sub 4}:Dy+PTFE pellets for high electron beam dosimetry, provided fading is correctly accounted for. - Highlights: Black-Right-Pointing-Pointer Developing of CaSO{sub 4}:Dy to electron beams dosimetry. Black-Right-Pointing-Pointer Characterization of caSO{sub 4}:Dy to radiation safety in LINACs. Black-Right-Pointing-Pointer TL characteristics of CaSO{sub 4}:Dy for electron beams quality control.

Model Insensitive and Calibration Independent Method for Determination of the Downstream Neutral Hydrogen Density Through Ly-alpha Glow Observations

Science.gov (United States)

Gangopadhyay, P.; Judge, D. L.

1996-01-01

Our knowledge of the various heliospheric phenomena (location of the solar wind termination shock, heliopause configuration and very local interstellar medium parameters) is limited by uncertainties in the available heliospheric plasma models and by calibration uncertainties in the observing instruments. There is, thus, a strong motivation to develop model insensitive and calibration independent methods to reduce the uncertainties in the relevant heliospheric parameters. We have developed such a method to constrain the downstream neutral hydrogen density inside the heliospheric tail. In our approach we have taken advantage of the relative insensitivity of the downstream neutral hydrogen density profile to the specific plasma model adopted. We have also used the fact that the presence of an asymmetric neutral hydrogen cavity surrounding the sun, characteristic of all neutral densities models, results in a higher multiple scattering contribution to the observed glow in the downstream region than in the upstream region. This allows us to approximate the actual density profile with one which is spatially uniform for the purpose of calculating the downstream backscattered glow. Using different spatially constant density profiles, radiative transfer calculations are performed, and the radial dependence of the predicted glow is compared with the observed I/R dependence of Pioneer 10 UV data. Such a comparison bounds the large distance heliospheric neutral hydrogen density in the downstream direction to a value between 0.05 and 0.1/cc.

Use of E-Beam for Shelf-Life Extension and Sanitizing of Marinated Pork Loin

Science.gov (United States)

García-Márquez, I.; Ordóñez, J. A.; Cambero, M. I.; Cabeza, M. C.

2012-01-01

The effectiveness of E-beam radiation to extend the shelf-life of marinated pork loin slices stored at 4 and 8°C (temperature abuse) has been studied. The shelf-life was extended from 7 to 16 and >20 days after the application of 1 and 2 kGy, respectively. In the event of a temperature abuse occuring during the product distribution (e.g., increase to 8°C), the shelf-life would be extended from 5 to 10 and 16 days, respectively, when applying the doses mentioned previously. From a public health point of view, the irradiation of marinated pork loin may be marketable for a longer period of time of up to two weeks, and guarantees a practically Salmonella and Listeria-free product. Minor changes are produced by the E-beam treatment in the main sensory and rheological characteristics. The odor was the most affected feature, but the off-odors diminished with increased storage. In any case, testers judged the samples to be adequate for marketing. PMID:23227053

Use of E-Beam for Shelf-Life Extension and Sanitizing of Marinated Pork Loin

Directory of Open Access Journals (Sweden)

I. García-Márquez

2012-01-01

Full Text Available The effectiveness of E-beam radiation to extend the shelf-life of marinated pork loin slices stored at 4 and 8°C (temperature abuse has been studied. The shelf-life was extended from 7 to 16 and >20 days after the application of 1 and 2 kGy, respectively. In the event of a temperature abuse occuring during the product distribution (e.g., increase to 8°C, the shelf-life would be extended from 5 to 10 and 16 days, respectively, when applying the doses mentioned previously. From a public health point of view, the irradiation of marinated pork loin may be marketable for a longer period of time of up to two weeks, and guarantees a practically Salmonella and Listeria-free product. Minor changes are produced by the E-beam treatment in the main sensory and rheological characteristics. The odor was the most affected feature, but the off-odors diminished with increased storage. In any case, testers judged the samples to be adequate for marketing.

Plasma actuators for active flow control based on a glow discharge

International Nuclear Information System (INIS)

Kühn, M.; Kühn-Kauffeldt, M.; Schein, J.; Belinger, A.

2017-01-01

In this work a glow discharge based active flow control for high flow velocities and low Reynolds numbers is presented. Unlike common plasma actuators such as dielectric barrier discharge (DBD) or spark jets, this actuator uses small impulse bits at frequencies. The actuator is optimized for frequencies up to 40 kHz to counter Tollmien Schlichting wave effects and so reduce overall air foil drag. Several measurements to prove the non-eroding effect of the actuator and the electrical properties were performed. It was found that the actuator is capable of operating at high frequencies without measurable erosion. (paper)

Visualisation of the high-current e-beams on solid surfaces

Energy Technology Data Exchange (ETDEWEB)

Solomonov, V I; Osipov, V V; Mikhajlov, S G; Lipchak, A I [Russian Academy of Sciences, Ural Division, Ekaterinburg (Russian Federation). Institute of Electrophysics

1997-12-31

Natural minerals such as spodumen, calcite, and Mn-doped apatite crystals may serve as suitable low-cost materials for visualization of high-current electron beams. High-intensity luminescence lasting several tens of minutes has been observed when irradiating natural specimen by electron beams with the current density of 10-1000 A/sq.cm, with energy of 100-300 keV, and pulse duration of 2-50 ns. The luminescent images of the beam cross-section provide information on the beam density profiles, while the images taken in the plane parallel to the beam axis make it possible to estimate the beam penetration depth and, therefore, the beam energy. The method is illustrated by examples of luminescent images taken from the experiment. (J.U.).

Structural investigation of e-beam cured epoxy resins through solid state NMR

International Nuclear Information System (INIS)

Alessi, Sabina; Spinella, Alberto; Caponetti, Eugenio; Dispenza, Clelia; Spadaro, Giuseppe

2012-01-01

In this paper the network structure of e-beam cured DGEBF based epoxy resins is investigated. Two epoxy systems, having different reactivity and cured in different process conditions, were analyzed through solid state NMR spectroscopy. The analysis shows that the more reactive system has higher cross-linking density and higher uniformity of network distribution. Similar information were obtained, in a previous work, on the same systems through dynamic mechanical thermal analysis. It is worth noting that unlike DMTA tests, which interfere with the molecular structure of the analyzed material, due to the heating during the analysis itself, more reliable information, without any artefact, are obtained by solid state NMR, carried out at constant room temperature. - Highlights: ► The structure of two e-beam cured epoxy systems is investigated through solid state NMR. ► The aim is to have direct information about the structure without inducing modifications. ► The different molecular structures are able to emphasize the response of solid state NMR. ► T 1 H, T 1ρ H and T CH measurements indicate different cross-linking degrees. ► The NMR results are in agreement with DMTA analysis performed in a previous paper.

The nonlocal electron kinetics for a low-pressure glow discharge dusty plasma

Science.gov (United States)

Liang, Yonggan; Wang, Ying; Li, Hui; Tian, Ruihuan; Yuan, Chengxun; Kudryavtsev, A. A.; Rabadanov, K. M.; Wu, Jian; Zhou, Zhongxiang; Tian, Hao

2018-05-01

The nonlocal electron kinetic model based on the Boltzmann equation is developed in low-pressure argon glow discharge dusty plasmas. The additional electron-dust elastic and inelastic collision processes are considered when solving the kinetic equation numerically. The orbital motion limited theory and collision enhanced collection approximation are employed to calculate the dust surface potential. The electron energy distribution function (EEDF), effective electron temperature Teff, and dust surface potential are investigated under different plasma and dust conditions by solving the Boltzmann and the dust charging current balance equations self-consistently. A comparison of the calculation results obtained from nonlocal and local kinetic models is made. It is shown that the appearance of dust particles leads to a deviation of the EEDF from its original profile for both nonlocal and local kinetic models. With the increase in dust density and size, the effective electron temperature and dust surface potential decrease due to the high-energy electron loss on the dust surface. Meanwhile, the nonlocal and local results differ much from each other under the same calculation condition. It is concluded that, for low-pressure (PR ≤ 1 cm*Torr) glow discharge dusty plasmas, the existence of dust particles will amplify the difference of local and nonlocal EEDFs, which makes the local kinetic model more improper to determine the main parameters of the positive column. The nonlocal kinetic model should be used for the calculation of the EEDFs and dusty plasma parameters.

Gas Temperature Measurement in a Glow Discharge Plasma

Science.gov (United States)

Sloneker, Kenneth; Podder, Nirmol; McCurdy, William E.; Shi, Shi

2009-10-01

In this study a relatively inexpensive quartz protected thermocouple is used to measure the gas temperature in the positive column of a glow discharge plasma. For simplicity a K-type thermocouple is used to interpret the gas temperature from the sensor voltage at pressures from 0.5 Torr to 15 Torr and discharge currents from 5 mA to 120 mA. Gas temperature is investigated as a function of the gas pressure at fixed discharge currents and as a function of discharge current at fixed gas pressures in three different gas species (Ar, N2, and He). An infinite cylinder model is used to compute the average gas temperature of the discharge from joule heating and gas thermal conductivity. The model and measurement data agree within 1% to 10% depending on plasma parameters. Data for all three gases have a similar quasi-linear increasing error as compared to the model.

Enhancing DC Glow Discharge Tube Museuum Displays using a Theremin Controlled Helmholtz Coil to Demonstrate Magnetic Confinement

Science.gov (United States)

Siu, Theodore; Wissel, Stephanie; Guttadora, Larry; Liao, Susan; Zwicker, Andrew

2010-11-01

Since their discovery in the mid 1800's, DC glow discharge apparatuses have commonly been used for spectral analysis, the demonstration of the Frank-Hertz experiment, and to study plasma breakdown voltages following from the Paschen Curve. A DC glow discharge tube museum display was outfitted with a Helmholtz Coil electromagnet in order to demonstrate magnetic confinement for a science museum display. A device commonly known as a ``theremin'' was designed and built in order to externally control the Helmholtz Coil current and the plasma current. Originally a musical instrument, a theremin has two variable capacitors connected to two radio frequency oscillators which determine pitch and volume. Using a theremin to control current and ``play'' the plasma adds appeal and durability by providing a new innovative means of interacting with a museum exhibit. Educationally, students can use the display to not only learn about plasma properties but also electronic properties of the human body.

PASOTRON high-energy microwave source

Science.gov (United States)

Goebel, Dan M.; Schumacher, Robert W.; Butler, Jennifer M.; Hyman, Jay, Jr.; Santoru, Joseph; Watkins, Ron M.; Harvey, Robin J.; Dolezal, Franklin A.; Eisenhart, Robert L.; Schneider, Authur J.

1992-04-01

A unique, high-energy microwave source, called PASOTRON (Plasma-Assisted Slow-wave Oscillator), has been developed. The PASOTRON utilizes a long-pulse E-gun and plasma- filled slow-wave structure (SWS) to produce high-energy pulses from a simple, lightweight device that utilizes no externally produced magnetic fields. Long pulses are obtained from a novel E-gun that employs a low-pressure glow discharge to provide a stable, high current- density electron source. The electron accelerator consists of a high-perveance, multi-aperture array. The E-beam is operated in the ion-focused regime where the plasma filling the SWS space-charge neutralizes the beam, and the self-pinch force compresses the beamlets and increases the beam current density. A scale-model PASOTRON, operating as a backward- wave oscillator in C-band with a 100-kV E-beam, has produced output powers in the 3 to 5 MW range and pulse lengths of over 100 microsecond(s) ec, corresponding to an integrated energy per pulse of up to 500 J. The E-beam to microwave-radiation power conversion efficiency is about 20%.

Analysis of iron-base alloys by low-wattage glow discharge emission spectrometry

International Nuclear Information System (INIS)

Wagatsuma, K.; Hirokawa, K.

1984-01-01

Several iron-base alloys were investigated by low-wattage glow discharge emission spectrometry. The emission intensity principally depended on the sputtering parameters of constituent elements in the alloy. However, in the case of chromium, stable and firm oxides formed on the surface influencing the yield of ejected atoms. This paper discusses the relation between the sputtering parameters in Fe-Ni, Fe-Cr, and Fe-Co alloys and their relative emission intensities. Additionally, quantitative analysis was performed for some ternary iron-base alloys and commercial stainless steels with the calibration factors of binary alloy systems

Radiative corrections to the beam spin asymmetry in photon electroproduction e polarized p {yields} ep{gamma}

Energy Technology Data Exchange (ETDEWEB)

Fonvieille, H.; Bensafa, I. [LPC-Clermont-Fd, Universite Blaise Pascal, F-63170 Aubiere Cedex (France)

2006-11-15