WorldWideScience

Sample records for nuclear electromagnetic pulse

  1. High-Altitude Electromagnetic Pulse (HEMP) Testing

    Science.gov (United States)

    2015-07-09

    Electromagnetic Pulse Horizontal Electromagnetic Pulse Advanced Fast Electromagnetic Pulse Nuclear Weapons Effect Testing and Environments 16. SECURITY...TOP 01-2-620A 9 July 2015 G-1 APPENDIX G. ABBREVIATIONS. AFEMP Advanced Fast Electromagnetic ... Electromagnetic Pulse A burst of electromagnetic radiation from a nuclear explosion or a suddenly fluctuating magnetic field. The resulting electric and

  2. Interaction of electromagnetic pulse with commercial nuclear-power-plant systems

    Energy Technology Data Exchange (ETDEWEB)

    Ericson, D.M. Jr.; Strawe, D.F.; Sandberg, S.J.; Jones, V.K.; Rensner, G.D.; Shoup, R.W.; Hanson, R.J.; Williams, C.B.

    1983-02-01

    This study examines the interaction of the electromagnetic pulse from a high altitude nuclear burst with commercial nuclear power plant systems. The potential vulnerability of systems required for safe shutdown of a specific nuclear power plant are explored. EMP signal coupling, induced plant response and component damage thresholds are established using techniques developed over several decades under Defense Nuclear Agency sponsorship. A limited test program was conducted to verify the coupling analysis technique as applied to a nuclear power plant. The results are extended, insofar as possible, to other nuclear plants.

  3. Development of Design Information Template for Nuclear Power Plants for Electromagnetic Pulse (EMP) Effect Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minyi; Ryu, Hosan; Ye, Songhae; Lee, Euijong [KNHP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    An electromagnetic pulse (EMP) is a transient electromagnetic shock wave that has powerful electric and magnetic fields that can destroy electronic equipment. It is generally well-known that EMPs can cause the malfunction and disorder of electronic equipment and serious damages to electric power systems and communication networks. Research is being carried out to protect nuclear power plants (NPPs) from EMP threats. Penetration routes of EMPs can be roughly categorized into two groups, radioactivity and conductivity. The radioactive effect refers to an impact transmitted to the ground from high-altitude electromagnetic pulses (HEMP). Such an impact may affect target equipment through the point of entry (POE) of the concrete structure of an NPP. The conductive effect refers to induced voltage or current coupled to the NPPs cable structure. The induced voltage and current affect the target equipment via connected cables. All these factors must be considered when taking into account EMP effect analysis for NPPs. To examine all factors, it is necessary to fully understand the schemes of NPPs. This paper presents a four type design information template that can be used to analyze the EMP effect in operating nuclear power plants. In order to analyze of the effects of EMPs on operating NPPs, we must consider both the conductive and radioactive effects on the target (system, equipment, structure). For these reasons, not only the equipment information, but also the information about the structure and the external penetration will be required. We are developing a design information template for robust nuclear design information acquisition. We expect to develop a block diagram on the basis of the template.

  4. The Establishment of Object Selection Criteria for Effect Analysis of Electromagnetic Pulse (EMP) in Operating Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Song Hae; Ryu, Hosun; Kim, Minyi; Lee, Euijong [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    The electromagnetic pulse (EMP) can be used as a strategic weapon by inducing damaging voltage and currents that the electrical circuits are not designed to withstand. EMPs are lethal to electronic systems. All EMP events have three common components: a source, coupling path, and receptor. It can also travel across power grids, destroying electronics as it passes in less than a second. There have been no research studies on the effect analysis for EMP in domestic nuclear power plants and power grids. To ensure the safety of operating nuclear power plants in this environment, the emission of EMP is needed for the effect analysis and safety measures against EMPs. Actually, it is difficult and inefficient to conduct the effect analysis of EMP with all the equipment and systems in nuclear power plants (NPPs). Therefore, this paper presents the results of establishing the object selection criteria for the effect analysis of EMP in operating nuclear power plants through reviewing previous research in the US and the safety related design concepts in domestic NPPs. It is not necessary to ensure the continued operation of the plant in intense multiple EMP environments. The most probable effect of EMP on a modern nuclear power plant is an unscheduled shutdown. EMP may also cause an extended shutdown by the unnecessary activation of some safety related systems. In general, EMP can be considered a nuisance to nuclear plants, but it is not considered a serious threat to plant safety. The results of EMP effect analysis show less possibility of failure in the tested individual equipment. It was also confirmed that there is no possibility of simultaneous failure for devices in charge of the safety shutdown in the NPP.

  5. Vertical Electromagnetic Pulse (VEMP) Testing

    Science.gov (United States)

    2009-09-11

    Device Measurement Accuracy Current Current Probes ±5% E-Field D-Dot Probe ±5% H-field B-Dot Probe ±5% Test Setup Digital Camera > 2 Megapixel...electromagnetic environment produced by a nuclear weapon consists of the ionization of the atmosphere and generation of an EMP. The gamma rays, neutrons , beta...Measurements . Measurements of each illumination will be made using an Electric Flux Density per unit time (D-dot) probes, so that the magnitude of

  6. Ultra-Wideband, Short Pulse Electromagnetics 9

    CERN Document Server

    Rachidi, Farhad; Kaelin, Armin; Sabath, Frank; UWB SP 9

    2010-01-01

    Ultra-wideband (UWB), short-pulse (SP) electromagnetics are now being used for an increasingly wide variety of applications, including collision avoidance radar, concealed object detection, and communications. Notable progress in UWB and SP technologies has been achieved by investigations of their theoretical bases and improvements in solid-state manufacturing, computers, and digitizers. UWB radar systems are also being used for mine clearing, oil pipeline inspections, archeology, geology, and electronic effects testing. Ultra-wideband Short-Pulse Electromagnetics 9 presents selected papers of deep technical content and high scientific quality from the UWB-SP9 Conference, which was held from July 21-25, 2008, in Lausanne, Switzerland. The wide-ranging coverage includes contributions on electromagnetic theory, time-domain computational techniques, modeling, antennas, pulsed-power, UWB interactions, radar systems, UWB communications, and broadband systems and components. This book serves as a state-of-the-art r...

  7. Exciting dynamic anapoles with electromagnetic doughnut pulses

    Science.gov (United States)

    Raybould, Tim; Fedotov, Vassili A.; Papasimakis, Nikitas; Youngs, Ian; Zheludev, Nikolay I.

    2017-08-01

    As was predicted in 1995 by Afanasiev and Stepanovsky, a superposition of electric and toroidal dipoles can lead to a non-trivial non-radiating charge current-configuration, the dynamic anapole. The dynamic anapoles were recently observed first in microwave metamaterials and then in dielectric nanodisks. However, spectroscopic studies of toroidal dipole and anapole excitations are challenging owing to their diminishing coupling to transverse electromagnetic waves. Here, we show that anapoles can be excited by electromagnetic Flying Doughnut (FD) pulses. First described by Helwarth and Nouchi in 1996, FD pulses (also known as "Flying Toroids") are space-time inseparable exact solutions to Maxwell's equations that have toroidal topology and propagate in free-space at the speed of light. We argue that FD pulses can be used as a diagnostic and spectroscopic tool for the dynamic anapole excitations in matter.

  8. Inertial confinement fusion driven by long wavelength electromagnetic pulses

    Institute of Scientific and Technical Information of China (English)

    Baifei; Shen; Xueyan; Zhao; Longqing; Yi; Wei; Yu; Zhizhan; Xu

    2013-01-01

    A method for inertial confinement fusion driven by powerful long wavelength electromagnetic pulses(EMPs), such as CO2 laser pulses or high power microwave pulses, is proposed. Due to the high efficiency of generating such long wavelength electromagnetic pulses, this method is especially important for the future fusion electricity power. Special fuel targets are designed to overcome the shortcomings of the long wavelength electromagnetic pulses.

  9. Pulsed thrust measurements using electromagnetic calibration techniques

    Energy Technology Data Exchange (ETDEWEB)

    Tang Haibin; Shi Chenbo; Zhang Xin' ai; Zhang Zun; Cheng Jiao [School of Astronautics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China)

    2011-03-15

    A thrust stand for accurately measuring impulse bits, which ranged from 10-1000 {mu}N s using a noncontact electromagnetic calibration technique is described. In particular, a permanent magnet structure was designed to produce a uniform magnetic field, and a multiturn coil was made to produce a calibration force less than 10 mN. The electromagnetic calibration force for pulsed thrust measurements was linear to the coil current and changed less than 2.5% when the distance between the coil and magnet changed 6 mm. A pulsed plasma thruster was first tested on the thrust stand, and afterward five single impulse bits were measured to give a 310 {mu}N s average impulse bit. Uncertainty of the measured impulse bit was analyzed to evaluate the quality of the measurement and was found to be 10 {mu}N s with 95% credibility.

  10. Charged particle interaction with a chirped electromagnetic pulse

    NARCIS (Netherlands)

    Khachatryan, A.G.; Boller, K.-J.; Goor, van F.A.

    2003-01-01

    It is found that a charged particle can get a net energy gain from the interaction with an electromagnetic chirped pulse. Theoretically, the energy gain increases with the pulse amplitude and with the relative frequency variation in the pulse.

  11. Nuclear pulse. III - Playing a wild card

    Science.gov (United States)

    Broad, W. J.

    1981-06-01

    Implications of the phenomenon of electromagnetic pulse (EMP), a high-voltage by-product of nuclear explosions in space which could render useless unprotected communications equipment and power grids over a wide area, for the feasibility of conducting a limited nuclear war by the United States are discussed. Arguments on the one hand that the effects of EMP demand direct investigation and should be protected against by the hardening of U.S. military communications are summarized and contrasted with those on the other hand which assert that the presence of EMP, as well as other exotic nuclear effects, would, despite any attempts at hardening, make it impossible to maintain the precision of command and control necessary for a limited nuclear action against Soviet military targets. Uncertainties about Soviet intentions in regard to the use of EMP as a weapon are also pointed out.

  12. Shaping metallic glasses by electromagnetic pulsing

    Science.gov (United States)

    Kaltenboeck, Georg; Demetriou, Marios D.; Roberts, Scott; Johnson, William L.

    2016-01-01

    With damage tolerance rivalling advanced engineering alloys and thermoplastic forming capabilities analogous to conventional plastics, metallic glasses are emerging as a modern engineering material. Here, we take advantage of their unique electrical and rheological properties along with the classic Lorentz force concept to demonstrate that electromagnetic coupling of electric current and a magnetic field can thermoplastically shape a metallic glass without conventional heating sources or applied mechanical forces. Specifically, we identify a process window where application of an electric current pulse in the presence of a normally directed magnetic field can ohmically heat a metallic glass to a softened state, while simultaneously inducing a large enough magnetic body force to plastically shape it. The heating and shaping is performed on millisecond timescales, effectively bypassing crystallization producing fully amorphous-shaped parts. This electromagnetic forming approach lays the groundwork for a versatile, time- and energy-efficient manufacturing platform for ultrastrong metals. PMID:26853460

  13. Shaping metallic glasses by electromagnetic pulsing

    Science.gov (United States)

    Kaltenboeck, Georg; Demetriou, Marios D.; Roberts, Scott; Johnson, William L.

    2016-02-01

    With damage tolerance rivalling advanced engineering alloys and thermoplastic forming capabilities analogous to conventional plastics, metallic glasses are emerging as a modern engineering material. Here, we take advantage of their unique electrical and rheological properties along with the classic Lorentz force concept to demonstrate that electromagnetic coupling of electric current and a magnetic field can thermoplastically shape a metallic glass without conventional heating sources or applied mechanical forces. Specifically, we identify a process window where application of an electric current pulse in the presence of a normally directed magnetic field can ohmically heat a metallic glass to a softened state, while simultaneously inducing a large enough magnetic body force to plastically shape it. The heating and shaping is performed on millisecond timescales, effectively bypassing crystallization producing fully amorphous-shaped parts. This electromagnetic forming approach lays the groundwork for a versatile, time- and energy-efficient manufacturing platform for ultrastrong metals.

  14. Control over spectral characteristics of electromagnetic pulses

    Energy Technology Data Exchange (ETDEWEB)

    Bolotov, V.N., E-mail: bolotov@ukrpost.u [Karazin National University, Kharkov 61007 (Ukraine); Fedorchenko, V.D.; Gritsenko, V.I.; Muratov, V.I. [Karazin National University, Kharkov 61007 (Ukraine)

    2010-05-01

    A theory was elaborated on transition radiation (TR) from electron bunches that pass through diaphragms of various geometries. At the base of this theory are induced charges and currents in the conductive diaphragms that are generated by electron bunches. An important role of the earth points of diaphragms was proven experimentally and theoretically. A feasibility study was made on controlling the spectra of electromagnetic pulses (EMP) and their directivity patterns. A new configuration for the diaphragms was proposed: twin diaphragms. Calculated and experimentally measured were spectra of such EMPs that were formed by the induced conduction current during the flight of the electron bunch through the twin diaphragms.

  15. Nuclear Pulse Propulsion

    OpenAIRE

    Atanas, Dilov; Hasan, Osman; Nickolai, Larsen; Tom, Edwards

    2015-01-01

    This project aims to provide the reader with a comprehensive insight into the potential of nuclear fuels to accelerate spacecraft propulsion, shorten journey times and broaden our exploration of space. The current methods of space propulsion offer little in the way of efficiency in terms of cost, time and henceforth investment and research. The dwindling resources of the planet plus the exponential rise of overpopulation will ultimately push us towards exploration of worlds further afield ...

  16. Interaction of ultrashort electromagnetic pulses with matter

    CERN Document Server

    Astapenko, Valeriy

    2013-01-01

    The book is devoted to the theory describing the interaction of  ultra-short electromagnetic pulses (USP) with matter, including both classical and quantum cases. This theme is a hot topic in modern physics because of the great achievements in generating USP. Special attention is given to the peculiarities of UPS-matter interaction. One of the important items of this book is the derivation and applications of a new formula which describes the total photo-process probability under the action of USP in the framework of perturbation theory. Strong field-matter interaction is also considered with the use of the Bloch formalism in a two-level approximation for UPS with variable characteristics.  

  17. Approaches to Simulating the Prompt Electromagnetic Pulse

    Science.gov (United States)

    Friedman, Alex; Cohen, Bruce I.; Eng, Chester D.; Farmer, William A.; Grote, David P.; Kruger, Hans W.; Larson, David J.

    2016-10-01

    LLNL is developing a suite of modern tools for simulating the generation and propagation of the prompt (E1) electromagnetic pulse (EMP). These include the 3-D EMPulse code, based on PIC methods with a Cartesian grid in the laboratory frame, and a companion 3-D approach which builds on the methods used in Longmire's fast-running CHAP code. In CHAP, and in our own CHAP-lite, 1-D spherical symmetry is assumed, and the calculation takes advantage of a separation of scales. The independent coordinates are (r, τ) , where r is the distance from the source and τ = t-r/c; the pulse varies slowly with r at fixed τ, so a coarse radial grid can be used. We seek similar efficiencies in 3-D, incorporating non-spherically-symmetric physics via a vector spherical harmonic decomposition. For each (l,m) harmonic, the radial equation is similar to that in CHAP-lite. We describe this approach, along with other aspects of our project. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  18. Minimizing the Effects of Electromagnetic Pulse (EMP) on Field Medical Equipment

    Science.gov (United States)

    1991-06-07

    Keep wiring short . Unplug unused equipment, Run power cabling and tents in a magnetic North-South direction. Avoid running power cabling in the East...electromagnetic pulse (EMP) is a radiated electromagnetic (EM) wave caused by the detonation of a nuclear weapcn above the earth’s atmosphere. A one megaton...Analyzer Endoscopic Light Source Ophthalmic Diathermy Flame Photometer These wudies demons rated that selected items of otherwise unprotected medical

  19. Birefringence effects of short probe pulses of electromagnetically induced transparency

    Science.gov (United States)

    Parshkov, Oleg M.; Kochetkova, Anastasia E.; Budyak, Victoria V.

    2016-04-01

    The numerical simulation results of radiations evolution in the presence of electromagnetically induced transparency for J=0-->J=1-->J=2 scheme of degenerate quantum transitions are presented. The pulse regime of wave interaction with Doppler broadening spectral lines was investigated. It was indicated that when the control field is linear polarized, the input circular polarized probe pulse breaks up in the medium into pulses with mutually perpendicular linear polarizations. Polarization direction of one of these pulses coincides with the polarization direction of control fields. The distance, which probe pulse passes in the medium to its full separation, decreases, when input probe pulse duration or control field intensity decreases. The input probe pulse intensity variation almost does not influence separation distance and speed of the linear polarized probe pulses in the medium. The effects, described above, may be interpreted as the birefringence effects of electromagnetically induced transparency in the case of short probe pulse.

  20. Electromagnetic pulsed thermography for natural cracks inspection

    Science.gov (United States)

    Gao, Yunlai; Tian, Gui Yun; Wang, Ping; Wang, Haitao; Gao, Bin; Woo, Wai Lok; Li, Kongjing

    2017-02-01

    Emerging integrated sensing and monitoring of material degradation and cracks are increasingly required for characterizing the structural integrity and safety of infrastructure. However, most conventional nondestructive evaluation (NDE) methods are based on single modality sensing which is not adequate to evaluate structural integrity and natural cracks. This paper proposed electromagnetic pulsed thermography for fast and comprehensive defect characterization. It hybrids multiple physical phenomena i.e. magnetic flux leakage, induced eddy current and induction heating linking to physics as well as signal processing algorithms to provide abundant information of material properties and defects. New features are proposed using 1st derivation that reflects multiphysics spatial and temporal behaviors to enhance the detection of cracks with different orientations. Promising results that robust to lift-off changes and invariant features for artificial and natural cracks detection have been demonstrated that the proposed method significantly improves defect detectability. It opens up multiphysics sensing and integrated NDE with potential impact for natural understanding and better quantitative evaluation of natural cracks including stress corrosion crack (SCC) and rolling contact fatigue (RCF).

  1. Electromagnetic pulsed thermography for natural cracks inspection

    Science.gov (United States)

    Gao, Yunlai; Tian, Gui Yun; Wang, Ping; Wang, Haitao; Gao, Bin; Woo, Wai Lok; Li, Kongjing

    2017-01-01

    Emerging integrated sensing and monitoring of material degradation and cracks are increasingly required for characterizing the structural integrity and safety of infrastructure. However, most conventional nondestructive evaluation (NDE) methods are based on single modality sensing which is not adequate to evaluate structural integrity and natural cracks. This paper proposed electromagnetic pulsed thermography for fast and comprehensive defect characterization. It hybrids multiple physical phenomena i.e. magnetic flux leakage, induced eddy current and induction heating linking to physics as well as signal processing algorithms to provide abundant information of material properties and defects. New features are proposed using 1st derivation that reflects multiphysics spatial and temporal behaviors to enhance the detection of cracks with different orientations. Promising results that robust to lift-off changes and invariant features for artificial and natural cracks detection have been demonstrated that the proposed method significantly improves defect detectability. It opens up multiphysics sensing and integrated NDE with potential impact for natural understanding and better quantitative evaluation of natural cracks including stress corrosion crack (SCC) and rolling contact fatigue (RCF). PMID:28169361

  2. Pulsed Electromagnetic Acceleration of Plasma: A Review

    Science.gov (United States)

    Thio, Y. C. Francis; Turchi, Peter J.; Markusic, Thomas E.; Cassibry, Jason T.; Sommer, James; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    Much have been learned in the acceleration mechanisms involved in accelerating a plasma electromagnetically in the laboratory over the last 40 years since the early review by Winston Bostik of 1963, but the accumulated understanding is very much scattered throughout the literature. This literature extends back at least to the early sixties and includes Rosenbluth's snowplow model, discussions by Ralph Lovberg, Colgate's boundary-layer model of a current sheet, many papers from the activity at Columbia by Robert Gross and his colleagues, and the relevant, 1-D unsteady descriptions developed from the U. of Maryland theta-pinch studies. Recent progress on the understanding of the pulsed penetration of magnetic fields into collisionless or nearly collisionless plasmas are also be reviewed. Somewhat more recently, we have the two-dimensional, unsteady results in the collisional regime associated with so-called wall-instability in large radius pinch discharges and also in coaxial plasma guns (e.g., Plasma Flow Switch). Among other things, for example, we have the phenomenon of a high- density plasma discharge propagating in a cooaxial gun as an apparently straight sheet (vs paraboloid) because mass re-distribution (on a microsecond timescale) compensates for the 1/r- squared variation of magnetic pressure. We will attempt to collate some of this vast material and bring some coherence tc the development of the subject.

  3. Design and Testing of Coils for Pulsed Electromagnetic Forming

    OpenAIRE

    Golovashchenko, S.; Bessonov, N.; Davies, R

    2006-01-01

    Coil design influences the distribution of electromagnetic forces applied to both the blank and the coil. The required energy of the process is usually defined by deformation of the blank. However, the discharge also results in a significant amount of heat being generated and accumulating in the coil. Therefore, EMF process design involves working with three different problems: 1) propagation of an electromagnetic field through the coil-blank system and generation of pulsed electromagnetic pr...

  4. Pulsed electromagnetic energy therapy in third molar surgery.

    Science.gov (United States)

    Hutchinson, D; Witt, S; Fairpo, C G

    1978-12-01

    Pulsed electromagnetic energy is being increasingly employed to reduced symptoms and enhance the healing process following tissue injury. A double-blind placebo-controlled trial has been carried out to assess the value of electromagnetic energy in third molar surgery, but no significant benefit has been found.

  5. Characteristics of Electromagnetic Pulse Coupling into Annular Apertures

    Directory of Open Access Journals (Sweden)

    Yan-Peng Sun

    2013-11-01

    Full Text Available Electromagnetic pulse (EMP coupling into the annular apertures can disturb or damage much electronic equipment. To enhance electronic system’s  capability of anti-electromagnetic interference, the finite difference time domain method (FDTD was employed to study the characteristics of electromagnetic pulse coupling into the cavity enclosures with annular apertures. The coupling characteristics of annular apertures with different shapes (rectangle, square and circle were discussed. It shows that, in the case of the same aperture area, the coupling energy of electromagnetic pulse into the circular annular aperture is smaller than that into the rectangular and the square ones. To the rectangular annular aperture, while the polarization direction of the incident electromagnetic pulse is perpendicular to the long side of the rectangular annular aperture, the coupling energy is larger when the aspect ratio of the rectangular annular aperture is larger. The coupling effect of incident pulse with short pulse width is obviously better than the one with longer pulse width. The resonance phenomenon of the coupled waveform occurs in the cavity.

  6. On e(+)e(-) pair production by colliding electromagnetic pulses

    NARCIS (Netherlands)

    Narozhny, NB; Bulanov, SS; Mur, VD; Popov, VS

    2004-01-01

    Electron-positron pair production from vacuum in an electromagnetic field created by two counterpropagating focused laser pulses interacting with each other is analyzed. The dependence of the number of produced pairs on the intensity of a laser pulse and the focusing parameter is studied with a real

  7. Interaction of free charged particles with a chirped electromagnetic pulse

    NARCIS (Netherlands)

    Khachatryan, A.G.; Goor, van F.A.; Boller, K.-J.

    2004-01-01

    We study the effect of chirp on electromagnetic (EM) pulse interaction with a charged particle. Both the one-dimensional (1D) and 3D cases are considered. It is found that, in contrast to the case of a nonchirped pulse, the charged particle energy can be changed after the interaction with a 1D EM ch

  8. Interim Report of the Defense Science Board (DSB) Task Force on the Survivability of Systems and Assets to Electromagnetic Pulse (EMP) and other Nuclear Weapon Effects (NWE)

    Science.gov (United States)

    2011-08-01

    major platforms for High Altitude EMP ( HEMP ) protection, and the Navy implemented a requirements review process. United States Strategic Command...Army improving process for independent review of survivability – Air Force committing resources for testing major platforms for HEMP protection...battlespaces where nuclear weapons are threatening or are being employed. The most likely case(s) are use of nuclear weapons by others. Although

  9. Electromagnetic studies of nucleon and nuclear structure

    Energy Technology Data Exchange (ETDEWEB)

    Heisenberg, J.H.; Calarco, J.R.; Hersman, F.W.; Dawson, J.F.

    1993-06-01

    Important objectives of the group are the study of subatomic structure through experimental measurements and the interpretation of the data through modeling. The common theme that unifies the studies of strong interactions and hadronic systems is the effort to determine the electromagnetic response as completely as possible. The general approach is coincidence detection of exclusive final states and determination of the dependence on the spin variables using polarized beams and targets and outgoing nucleon polarimetry. Direct reaction and giant resonance studies of electron quasi-elastic scattering on {sup 12}C and {sup 16}O are reported, as well as work on nuclear structure models and instrumentation development.

  10. Phase measurement of fast light pulse in electromagnetically induced absorption.

    Science.gov (United States)

    Lee, Yoon-Seok; Lee, Hee Jung; Moon, Han Seb

    2013-09-23

    We report the phase measurement of a fast light pulse in electromagnetically induced absorption (EIA) of the 5S₁/₂ (F = 2)-5P₃/₂ (F' = 3) transition of ⁸⁷Rb atoms. Using a beat-note interferometer method, a stable measurement without phase dithering of the phase of the probe pulse before and after it has passed through the EIA medium was achieved. Comparing the phases of the light pulse in air and that of the fast light pulse though the EIA medium, the phase of the fast light pulse at EIA resonance was not shifted and maintained to be the same as that of the free-space light pulse. The classical fidelity of the fast light pulse according to the advancement of the group velocity by adjusting the atomic density was estimated to be more than 97%.

  11. Transcranial stimulability of phosphenes by long lightning electromagnetic pulses

    CERN Document Server

    Peer, J

    2010-01-01

    The electromagnetic pulses of rare long (order of seconds) repetitive lightning discharges near strike point (order of 100m) are analyzed and compared to magnetic fields applied in standard clinical transcranial magnetic stimulation (TMS) practice. It is shown that the time-varying lightning magnetic fields and locally induced potentials are in the same order of magnitude and frequency as those established in TMS experiments to study stimulated perception phenomena, like magnetophosphenes. Lightning electromagnetic pulse induced transcranial magnetic stimulation of phosphenes in the visual cortex is concluded to be a plausible interpretation of a large class of reports on luminous perceptions during thunderstorms.

  12. Translation and Rotation of Transformation Media under Electromagnetic Pulse

    CERN Document Server

    Gao, Fei; Lin, Xiao; Xu, Hongyi; Zhang, Baile

    2016-01-01

    It is well known that optical media create artificial geometry for light, and curved geometry acts as an effective optical medium. This correspondence originates from the form invariance of Maxwells equations, which recently has spawned a booming field called transformation optics. Here we investigate responses of three transformation media under electromagnetic pulses, and find that pulse radiation can induce unbalanced net force on transformation media, which will cause translation and rotation of transformation media although their final momentum can still be zero. Therefore, the transformation media do not necessarily stay the same after an electromagnetic wave passes through.

  13. Translation and Rotation of Transformation Media under Electromagnetic Pulse

    Science.gov (United States)

    Gao, Fei; Shi, Xihang; Lin, Xiao; Xu, Hongyi; Zhang, Baile

    2016-06-01

    It is well known that optical media create artificial geometry for light, and curved geometry acts as an effective optical medium. This correspondence originates from the form invariance of Maxwell’s equations, which recently has spawned a booming field called ‘transformation optics’. Here we investigate responses of three transformation media under electromagnetic pulses, and find that pulse radiation can induce unbalanced net force on transformation media, which will cause translation and rotation of transformation media although their final momentum can still be zero. Therefore, the transformation media do not necessarily stay the same after an electromagnetic wave passes through.

  14. Nonlinear dynamics of electromagnetic pulses in cold relativistic plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bonatto, A.; Pakter, R.; Rizzato, F.B. [Universidade Federal do Rio Grande do Sul, Instituto de Fisica, Rio Grande do Sul (Brazil)

    2004-07-01

    The propagation of intense electromagnetic pulses in plasmas is a subject of current interest particularly for particle acceleration and laser fusion.In the present analysis we study the self consistent propagation of nonlinear electromagnetic pulses in a one dimensional relativistic electron-ion plasma, from the perspective of nonlinear dynamics. We show how a series of Hamiltonian bifurcations give rise to the electric fields which are of relevance in the subject of particle acceleration. Connections between these bifurcated solutions and results of earlier analysis are made. (authors)

  15. Transcranial stimulability of phosphenes by long lightning electromagnetic pulses

    Energy Technology Data Exchange (ETDEWEB)

    Peer, J. [Institut fuer Ionenphysik und Angewandte Physik, Universitaet Innsbruck, A-6020 Innsbruck (Austria); Kendl, A., E-mail: alexander.kendl@uibk.ac.a [Institut fuer Ionenphysik und Angewandte Physik, Universitaet Innsbruck, A-6020 Innsbruck (Austria)

    2010-06-28

    The electromagnetic pulses of rare long (order of seconds) repetitive lightning discharges near strike point (order of 100 m) are analyzed and compared to magnetic fields applied in standard clinical transcranial magnetic stimulation (TMS) practice. It is shown that the time-varying lightning magnetic fields and locally induced electric fields are in the same order of magnitude and frequency as those established in TMS experiments to study stimulated perception phenomena, like magnetophosphenes. Lightning electromagnetic pulse induced transcranial magnetic stimulation of phosphenes in the visual cortex is concluded to be a plausible interpretation of a large class of reports on luminous perceptions during thunderstorms.

  16. Translation and Rotation of Transformation Media under Electromagnetic Pulse

    Science.gov (United States)

    Gao, Fei; Shi, Xihang; Lin, Xiao; Xu, Hongyi; Zhang, Baile

    2016-01-01

    It is well known that optical media create artificial geometry for light, and curved geometry acts as an effective optical medium. This correspondence originates from the form invariance of Maxwell’s equations, which recently has spawned a booming field called ‘transformation optics’. Here we investigate responses of three transformation media under electromagnetic pulses, and find that pulse radiation can induce unbalanced net force on transformation media, which will cause translation and rotation of transformation media although their final momentum can still be zero. Therefore, the transformation media do not necessarily stay the same after an electromagnetic wave passes through. PMID:27321246

  17. Preliminary analysis of electromagnetic pulse generated by nuclear explosions in space with case signal model%深空核爆炸辐射电磁脉冲的初步解析

    Institute of Scientific and Technical Information of China (English)

    朱梦; 周辉; 程引会; 李宝忠; 吴伟; 李进玺; 马良; 赵墨

    2011-01-01

    A preliminary understanding of electromagnetic pulse generated by nuclear explosions in space has been developed with case signal model. For observers in large distances, a net dipole can be resulted from the average movements of space charges. Based on the law of electron movements, the electric dipole moment of the whole system has been analytically described. The radiation fields are closely related to the derivatives of the dipole moment with time. The peak value of radiation signal in far field increases linearly with the initial kinetic energies of electrons, and quadratically with the radius of bomb and with the rise time constant. The peak is irrelevant to explosion yield, while the peak time will be postponed as the yield decreases.%采用壳模型分析深空核爆在远场产生辐射电磁脉冲的规律,对深空核爆电磁脉冲的形成机理进行研究.在已知电子运动规律的前提下,推导了发射电子的电偶极矩表达式,并得到了辐射电磁脉冲的特性.计算结果表明:远处辐射场的峰值电场与爆炸当量无关,但达到峰值的时间随爆炸当量增加而提前;电子初始动能的增大也能线性地提高峰值强度;峰值强度与上升时间常数及弹体半径的平方成正比.

  18. Comparison of Electric Dipole and Magnetic Dipole Models for Electromagnetic Pulse Generated by Nuclear Detonation in Space%两种深空核爆炸辐射电磁脉冲模型的比较

    Institute of Scientific and Technical Information of China (English)

    朱梦; 周辉; 程引会; 李宝忠; 吴伟; 李进玺; 马良; 赵墨

    2013-01-01

    深空核爆炸通过电偶极子和磁偶极子两种辐射机制产生电磁脉冲.本文具体分析了两种辐射模型产生电磁脉冲的物理机制,并估算了远处观察点的辐射电场.计算表明,电子以高斯波形出射时,百吨TNT当量爆炸在km量级范围内产生的电偶极子和磁偶极子辐射电场强度分别为kV/m和10 V/m量级.深空中地磁感应强度较弱,电子的角向运动相比初始方向运动是小量,因而磁偶极子的辐射强度远小于电偶极子的.%Electromagnetic pulse can be generated by the nuclear detonation in space via two radiation mechanisms.The electric dipole and magnetic dipole models were analyzed.The electric radiation in the far field generated by two models was calculated as well.Investigations show that in the case of one hundred TNT yield detonations,when electrons are emitted according to the Gaussian shape,two radiation models can give rise to the electric field in great distances with amplitudes of kV/m and tens of V/m,independently.Because the geomagnetic field in space is not strong and the electrons' angular motion is much weaker than the motion in the original direction,radiations from the magnetic dipole model are much weaker than those from the electric dipole model.

  19. Numerical simulation of the early-time high altitude electromagnetic pulse

    Institute of Scientific and Technical Information of China (English)

    孟萃; 陈雨生; 刘顺坤; 谢秦川; 陈向跃; 龚建成

    2003-01-01

    In this paper, the finite difference method is used to develop the Fortran software MCHII. The physical process in which the electromagnetic signal is generated by the interaction of nuclear-explosion-induced Compton currents with the geomagnetic field is numerically simulated. The electromagnetic pulse waveforms below the burst point are investigated.The effects of the height of burst, yield and the time-dependence of ?-rays are calculated by using the MCHII code.The results agree well with those obtained by using the code CHAP.

  20. Transcranial pulsed electromagnetic fields for multiple chemical sensitivity

    DEFF Research Database (Denmark)

    Tran, Marie Thi Dao; Skovbjerg, Sine; Arendt-Nielsen, Lars

    2013-01-01

    . The symptoms may have severe impact on patients' lives, but an evidence-based treatment for the condition is nonexisting. The pathophysiology is unclarified, but several indicators point towards abnormal processing of sensory signals in the central nervous system. Pulsed electromagnetic fields (PEMF) offer...

  1. Transcranial pulsed electromagnetic fields for multiple chemical sensitivity

    DEFF Research Database (Denmark)

    Tran, Marie Thi Dao; Skovbjerg, Sine; Arendt-Nielsen, Lars

    2013-01-01

    . The symptoms may have severe impact on patients' lives, but an evidence-based treatment for the condition is nonexisting. The pathophysiology is unclarified, but several indicators point towards abnormal processing of sensory signals in the central nervous system. Pulsed electromagnetic fields (PEMF) offer...

  2. Active absorption of electromagnetic pulses in a cavity

    CERN Document Server

    Horsley, S A R; Tyc, T; Philbin, T G

    2014-01-01

    We show that a pulse of electromagnetic radiation launched into a cavity can be completely absorbed into an infinitesimal region of space, provided one has a high degree of control over the current flowing through this region. We work out explicit examples of this effect in a cubic cavity and a cylindrical one, and experimentally demonstrate the effect in the microwave regime.

  3. Effect of pulsed electromagnetic fields on orthodontic tooth movement.

    Science.gov (United States)

    Stark, T M; Sinclair, P M

    1987-02-01

    The purpose of this study was to determine whether the application of a simple surgically noninvasive, pulsed electromagnetic field could increase both the rate and amount of orthodontic tooth movement observed in guinea pigs. In addition, the objective was to evaluate the electromagnetic field's effects on bony physiology and metabolism and to search for possible systemic side effects. Laterally directed orthodontic force was applied to the maxillary central incisors of a sample of 40 young male, Hartley guinea pigs (20 experimental, 20 control) by means of a standardized intraoral coil spring inserted under constricting pressure into holes drilled in the guinea pigs' two maxillary central incisors. During the experimental period, the guinea pigs were placed in specially constructed, plastic animal holders with their heads positioned in an area of uniform electromagnetic field. Control animals were placed in similar plastic holders that did not carry the electrical apparatus. The application of a pulsed electromagnetic field to the experimental animals significantly increased both the rate and final amount of orthodontic tooth movement observed over the 10-day experimental period. The experimental animals also demonstrated histologic evidence of significantly greater amounts of bone and matrix deposited in the area of tension between the orthodontically moved maxillary incisors. This increase in cellular activity was also reflected by the presence of significantly greater numbers of osteoclasts in the alveolar bone surrounding the maxillary incisors of the experimental animals. After a 10-day exposure to pulsed electromagnetic field, minor changes in serologic parameters relating to protein metabolism and muscle activity were noted. The results of this study suggest that it is possible to increase the rate of orthodontic tooth movement and bone deposition through the application of a noninvasive, pulsed electromagnetic field.

  4. A 16 MJ compact pulsed power system for electromagnetic launch

    Science.gov (United States)

    Dai, Ling; Zhang, Qin; Zhong, Heqing; Lin, Fuchang; Li, Hua; Wang, Yan; Su, Cheng; Huang, Qinghua; Chen, Xu

    2015-07-01

    This paper has established a compact pulsed power system (PPS) of 16 MJ for electromagnetic rail gun. The PPS consists of pulsed forming network (PFN), chargers, monitoring system, and current junction. The PFN is composed of 156 pulse forming units (PFUs). Every PFU can be triggered simultaneously or sequentially in order to obtain different total current waveforms. The whole device except general control table is divided into two frameworks with size of 7.5 m × 2.2 m × 2.3 m. It is important to estimate the discharge current of PFU accurately for the design of the whole electromagnetic launch system. In this paper, the on-state characteristics of pulse thyristor have been researched to improve the estimation accuracy. The on-state characteristics of pulse thyristor are expressed as a logarithmic function based on experimental data. The circuit current waveform of the single PFU agrees with the simulating one. On the other hand, the coaxial discharge cable is a quick wear part in PFU because the discharge current will be up to dozens of kA even hundreds of kA. In this article, the electromagnetic field existing in the coaxial cable is calculated by finite element method. On basis of the calculation results, the structure of cable is optimized in order to improve the limit current value of the cable. At the end of the paper, the experiment current wave of the PPS with the load of rail gun is provided.

  5. Merging Infrasound and Electromagnetic Signals as a Means for Nuclear Explosion Detection

    Science.gov (United States)

    Ashkenazy, Joseph; Lipshtat, Azi; Kesar, Amit S.; Pistinner, Shlomo; Ben Horin, Yochai

    2016-04-01

    The infrasound monitoring network of the CTBT consists of 60 stations. These stations are capable of detecting atmospheric events, and may provide approximate location within time scale of a few hours. However, the nature of these events cannot be deduced from the infrasound signal. More than two decades ago it was proposed to use the electromagnetic pulse (EMP) as a means of discriminating nuclear explosion from other atmospheric events. An EMP is a unique signature of nuclear explosion and is not detected from chemical ones. Nevertheless, it was decided to exclude the EMP technology from the official CTBT verification regime, mainly because of the risk of high false alarm rate, due to lightning electromagnetic pulses [1]. Here we present a method of integrating the information retrieved from the infrasound system with the EMP signal which enables us to discriminate between lightning discharges and nuclear explosions. Furthermore, we show how spectral and other characteristics of the electromagnetic signal emitted from a nuclear explosion are distinguished from those of lightning discharge. We estimate the false alarm probability of detecting a lightning discharge from a given area of the infrasound event, and identifying it as a signature of a nuclear explosion. We show that this probability is very low and conclude that the combination of infrasound monitoring and EMP spectral analysis may produce a reliable method for identifying nuclear explosions. [1] R. Johnson, Unfinished Business: The Negotiation of the CTBT and the End of Nuclear Testing, United Nations Institute for Disarmament Research, 2009.

  6. Transform of Lightning Electromagnetic Pulses Based on Laplace Wavelet

    Directory of Open Access Journals (Sweden)

    Qin Li

    2013-09-01

    Full Text Available In this study, the fine structures of lightning electromagnetic pulse associated with 19 preliminary breakdown pulses, 37 stepped leaders, 8 dart leaders, 73 first and 52 subsequent return strokes were analyzed by using Laplace wavelet. The main characteristics of field waveforms such as, the correlation coefficient, the time of arrival and the dominant frequency of the initial peak field, the energy and the frequency of the power spectrum peak are presented. The instantaneous initial peak field pulse can be precisely located by the value of the correlation coefficient. The dominant frequencies of the initial peak field of PB pulses and leaders range from 100 kHz to 1 MHz, and that of the first and subsequent return strokes below 100 and 50 kHz, respectively. The statistical results show that the Laplace wavelet is an effective tool and can be used to determine time and frequency of the lightning events with greater accuracy.  

  7. Pulsed Electromagnetic Field Assisted in vitro Electroporation: A Pilot Study

    Science.gov (United States)

    Novickij, Vitalij; Grainys, Audrius; Lastauskienė, Eglė; Kananavičiūtė, Rūta; Pamedytytė, Dovilė; Kalėdienė, Lilija; Novickij, Jurij; Miklavčič, Damijan

    2016-09-01

    Electroporation is a phenomenon occurring due to exposure of cells to Pulsed Electric Fields (PEF) which leads to increase of membrane permeability. Electroporation is used in medicine, biotechnology, and food processing. Recently, as an alternative to electroporation by PEF, Pulsed ElectroMagnetic Fields (PEMF) application causing similar biological effects was suggested. Since induced electric field in PEMF however is 2–3 magnitudes lower than in PEF electroporation, the membrane permeabilization mechanism remains hypothetical. We have designed pilot experiments where Saccharomyces cerevisiae and Candida lusitaniae cells were subjected to single 100–250 μs electrical pulse of 800 V with and without concomitant delivery of magnetic pulse (3, 6 and 9 T). As expected, after the PEF pulses only the number of Propidium Iodide (PI) fluorescent cells has increased, indicative of membrane permeabilization. We further show that single sub-millisecond magnetic field pulse did not cause detectable poration of yeast. Concomitant exposure of cells to pulsed electric (PEF) and magnetic field (PMF) however resulted in the increased number PI fluorescent cells and reduced viability. Our results show increased membrane permeability by PEF when combined with magnetic field pulse, which can explain electroporation at considerably lower electric field strengths induced by PEMF compared to classical electroporation.

  8. Effects of pulsed electromagnetic fields on benign prostate hyperplasia.

    Science.gov (United States)

    Giannakopoulos, Xenophon K; Giotis, Christos; Karkabounas, Spyridon Ch; Verginadis, Ioannis I; Simos, Yannis V; Peschos, Dimitrios; Evangelou, Angelos M

    2011-12-01

    Benign prostate hyperplasia (BPH) has been treated with various types of electromagnetic radiation methods such as transurethral needle ablation (TUNA), interstitial laser therapy (ILC), holmium laser resection (HoLRP). In the present study, the effects of a noninvasive method based on the exposure of patients with BPH to a pulsative EM Field at radiofrequencies have been investigated. Twenty patients with BPH, aging 68-78 years old (y.o), were enrolled in the study. Patients were randomly divided into two groups: the treatment group (10 patients, 74.0 ± 5.7 y.o) treated with the α-blocker Alfusosin, 10 mg/24 h for at least 4 weeks, and the electromagnetic group (10 patients, 73.7 ± 6.3 y.o) exposed for 2 weeks in a very short wave duration, pulsed electromagnetic field at radiofrequencies generated by an ion magnetic inductor, for 30 min daily, 5 consecutive days per week. Patients of both groups were evaluated before and after drug and EMF treatment by values of total PSA and prostatic PSA fraction, acid phosphate, U/S estimation of prostate volume and urine residue, urodynamic estimation of urine flow rate, and International Prostate Symptom Score (IPSS). There was a statistically significant decrease before and after treatment of IPSS (P < 0.02), U/S prostate volume (P < 0.05), and urine residue (P < 0.05), as well as of mean urine flow rate (P < 0.05) in patients of the electromagnetic group, in contrast to the treatment group who had only improved IPSS (P < 0.05). There was also a significant improvement in clinical symptoms in patients of the electromagnetic group. Follow-up of the patients of this group for one year revealed that results obtained by EMFs treatment are still remaining. Pulsed electromagnetic field at radiofrequencies may benefit patients with benign prostate hyperplasia treated by a non-invasive method.

  9. Pulsed electromagnetic stimulation in nonunion of tibial diaphyseal fractures

    Directory of Open Access Journals (Sweden)

    Gupta Anil

    2009-01-01

    Full Text Available Background: Nonunion of long bones is a difficult clinical problem and challenges the clinical acumen of surgeons. Multiple surgical or nonsurgical modalities have been used to treat nonunions. Noninvasive pulsed electromagnetic stimulation is an entity known to affect the piezoelectric phenomenon of bone forming cells. We conducted a study on 45 long-bone fractures of tibia treated by pulsed electromagnetic stimulation, which are analyzed and reported. Materials and Methods: A total of 45 tibial fractures with established atrophic nonunion were enrolled between 1981 and 1988. All the patients had abnormal mobility and no or minimal gap at fracture site with no evidence of callus formation across the fracture site. The patients′ age ranged between 24 and 68 years; 40 were men and 5 were women. All patients having evidence of infection, implant in situ , and gap nonunions were excluded from study. Pulsed electromagnetic stimulation was given using above-knee plaster of Paris cast (0.008 Weber/m 2 magnetic field was created for 12 h/day. The average duration for pulsed electromagnetic stimulation (PEMS therapy was 8.35 weeks, with the range being 6-12 weeks. The cases were evaluated at 6 weeks and subsequently every 6-weekly interval for clinical and radiological union. The withdrawal of therapy was decided as per clinicoradiological evidence of union. Results: All but three patients showed evidence of union. About 35% (n = 16 cases showed union in 10 weeks, and 85% (n = 38 cases showed union in 4 months. The average duration of therapy using PEMS was 8.35±0.48 weeks, and the average duration of immobilization was 3.02 ± 0.22 months. Three cases that did not show evidence of union were poorly compliant for the apparatus of PEMS. Conclusion: PEMS is a useful noninvasive modality of treatment for difficult nonunion of long bones.

  10. Detachment of Conductive Coatings by Pulsed Electromagnetic Field

    OpenAIRE

    Mironov, V.; Tatarinov, A.; Kolbe, M; Gluschenkov, V.

    2016-01-01

    The paper presents results of studies on the detachment of conductive coatings from the metal substrate by pulsed electromagnetic field (PEMF). It is known that at the boundary of a metal substrate and an electrically conductive coating having different electrical conductivities sharp changes of PEMF strength arise. This effect has been used to remove a copper layer from a steel substrate. Experimental studies were carried out in the Riga Technical University (Latvia), West Sax...

  11. Electromagnetic Pulse - A Catastrophic Threat to the Homeland

    Science.gov (United States)

    2011-03-24

    which could be very destructive to the electrical power grid. 3 A high altitude electromagnetic pulse ( HEMP ), caused by the detonation of a...recreate EMP on a large enough scale to draw reliable conclusions. But history has provided us with a few historical events to learn from. In 1962 the...circuit board systems used today are much more sensitive and vulnerable to EMP than the solid state, vacuum tube systems used 50 years ago

  12. Effects of Pulsed Electromagnetic Fields on Osteoporosis Model

    Science.gov (United States)

    Xiaowei, Yang; Liming, Wang; Guan, Z. C.; Yaou, Zhang; Xiangpeng, Wang

    The purpose of this paper was to investigate the preventive effects and long term effects of extremely low frequency pulsed electromagnetic fields (PEMFs), generated by circular coils and pulsed electromagnetic fields stimulators, on osteoporosis in bilaterally ovariectomized rats. In preventive experiment, thirty three-month old female Sprague-Dawley rats were randomly divided into three different groups: sham (SHAM), ovariectomy (OVX), PEMFs stimulation (PEMFs). All rats were subjected to bilaterally ovariectomy except those in SHAM group. The PEMFs group was exposed to pulsed electromagnetic fields with frequency 15 Hz, peak magnetic induction density 2.2mT and exposure time 2 hours per day. The bone mineral density (BMD) of vertebra and left femur were measured by dual energy X-ray absorptiometry at eighth week, twelfth week and sixteenth week after surgery. In long term effects experiment, forty four rats were randomly divided into sham (14 rats, SHAM), ovariectomy group (10 rats, OVX), 15Hz PEMFs group(10 rats, 15Hz) and 30Hz PEMFs group(10 rats, 30Hz) at twenty-sixth week after surgery. Rats in PEMFs groups were stimulated sixteen weeks. In preventive experiment, the Corrected BMD of vertebra and femur was significantly higher than that of OVX group after 16 weeks (Ptreatment of osteoporosis.

  13. Rydberg Wave Packets and Half-Cycle Electromagnetic Pulses

    Science.gov (United States)

    Raman, Chandra S.

    1998-05-01

    This dissertation summarizes an examination of the dynamics of atomic Rydberg wave packets with coherent pulses of THz electromagnetic radiation consisting of less than a single cycle of the electric field. The bulk of the energy is contained in just a half-cycle. Previous work ( R. Jones, D. You, and P. Bucksbaum, ``Ionization of Rydberg atoms by subpicosecond half-cycle electromagnetic pulses,'' Phys. Rev. Lett.), vol. 70, 1993. had shown how these half-cycle pulses can be used to ionize the highly excited states of an atom, and that a classical view of electronic motion in the atom explains the ionization mechanism. To further probe the boundary between classical trajectories and quantum mechanics, in this work I investigate dynamical combinations of Rydberg states, or Rydberg wave packets, and how they ionize under the influence of a half-cycle electromagnetic pulse. With time-domain techniques I am able to extract the dynamics of the wave packet from the ionization rate, and to observe wave packet motion in both the electronic radial ( C. Raman, C. Conover, C. Sukenik, and P. Bucksbaum, ``Ionization of Rydberg wavepackets by sub-picosecond half-cycle electromagnetic pulses,'' Phys. Rev. Lett.), vol. 76, 1996.and angular ( C. Raman, T. Weinacht, and P. Bucksbaum, ``Stark wavepackets viewed with half cycle pulses.'' Phys. Rev. A), vol. 55, No. 6, 1997. coordinates. This is the first time a wavepacket technique has been used to view electron motion everywhere on its trajectory, and not just at the nucleus. This is the principal feature of half-cycle pulse ionization. Semiclassical ideas of ionization in conjunction with quantum descriptions of the wave packet, are capable of reproducing the main trends in the data, and in the absence of a rigorous model I rely on these. Experiments of this nature provide examples of the ongoing effort to use the coherent properties of radiation to control electronic motion in an atom, as well as to probe the boundaries between

  14. Stopping x-ray pulses in a thin-film cavity via electromagnetically induced transparency

    CERN Document Server

    Kong, Xiangjin

    2015-01-01

    Stopping light via an electromagnetically induced transparency setup for x-ray pulses in a thin film planar x-ray cavity is investigated theoretically. The pulse is nearly resonant to the 14.4 keV M\\"ossbauer transition in $^{57}\\mathrm{Fe}$, with one nm-thin layer of the latter embedded in the thin-film x-ray cavity. Via a moderate hyperfine magnetic field which takes over the role of the control field, electromagnetically induced transparency and slowing down of the x-ray pulse occurs in the cavity setup. We show that by switching off the control magnetic field, a narrowband x-ray pulse can be completely stored in the cavity for approx. hundred ns. Coherent storage occurs in this scenario by imprinting the x-ray field onto nuclear coherences in a controllable and robust manner. Additional manipulation of the external magnetic field can lead to both group velocity and phase control of the pulse in the x-ray cavity sample.

  15. Effects of Electromagnetic Pulses on a Multilayered System

    Science.gov (United States)

    2014-07-01

    University at Buffalo, 230 Davis Hall, Buffalo, NY 14260 H. L. Moore, P. Haney US Army ARDEC, AMSRD-AAR-MEM, Building 65 S, Picatinny Arsenal, NJ...types of EMPs that are of concern regarding electronics and system infrastructures; they are high-altitude EMP ( HEMP ) generated from nuclear...is for 3-D full-wave electromagnetic field simulation and high frequency and high speed components [2]. The model used was designed and imported

  16. Measurement of Ultra-Short Solitary Electromagnetic Pulses

    Directory of Open Access Journals (Sweden)

    Eva Gescheidtova

    2004-01-01

    Full Text Available In connection with the events of the last few years and with the increased number of terrorist activities, the problem of identification and measurement of electromagnetic weapons or other systems impact occurred. Among these are also microwave sources, which can reach extensive peak power of up to Pmax = 100 MW. Solitary, in some cases several times repeated, impulses lasting from tp E <1, 60>ns, cause the destruction of semiconductor junctions. These days we can find scarcely no human activity, where semiconductor structures are not used. The problem of security support of the air traffic, transportation, computer nets, banks, national strategic data canter’s, and other applications crops up. Several types of system protection from the ultra-short electromagnetic pulses present itself, passive and active protection. The analysis of the possible measuring methods, convenient for the identification and measurement of the ultra-short solitary electromagnetic pulses in presented in this paper; some of the methods were chosen and used for practical measurement. This work is part of Research object MSM262200022 "Research of microelectronic systems".

  17. Octet baryon electromagnetic form factors in nuclear medium

    CERN Document Server

    Ramalho, G; Thomas, A W

    2012-01-01

    We study the octet baryon electromagnetic form factors in nuclear matter using the covariant spectator quark model extended to the nuclear matter regime. The parameters of the model in vacuum are fixed by the study of the octet baryon electromagnetic form factors. In nuclear matter the changes in hadron properties are calculated by including the relevant hadron masses and the modification of the pion-baryon coupling constants calculated in the quark-meson coupling model. In nuclear matter the magnetic form factors of the octet baryons are enhanced in the low $Q^2$ region, while the electric form factors show a more rapid variation with $Q^2$. The results are compared with the modification of the bound proton electromagnetic form factors observed at Jefferson Lab. In addition, the corresponding changes for the bound neutron are predicted.

  18. Effect of pulsed electromagnetic field on inflammatory pathway markers in RAW 264.7 murine macrophages

    Directory of Open Access Journals (Sweden)

    Ross CL

    2013-03-01

    Full Text Available Christina L Ross,1,2 Benjamin S Harrison2 1Akamai University, Department of Energy Medicine, Hilo, HI, USA; 2Wake Forest Institute for Regenerative Medicine, Wake Forest Baptist Health, Winston-Salem, NC, USA Abstract: In the treatment of bacterial infections, antibiotics have proven to be very effective, but the way in which antibiotics are dosed can create a lag time between the administration of the drug and its absorption at the site of insult. The time it takes an antibiotic to reach therapeutic levels can often be significantly increased if the vascular system is compromized. Bacteria can multiply pending the delivery of the drug, therefore, developing treatments that can inhibit the inflammatory response while waiting for antibiotics to take effect could help prevent medical conditions such as septic shock. The aim of this study was to examine the effect of a pulsed electromagnetic field on the production of inflammatory markers tumor necrosis factor (TNF, transcription factor nuclear factor kappa B (NFkB, and the expression of the A20 (tumor necrosis factor-alpha-induced protein 3, in an inflamed-cell model. Lipopolysaccharide-challenged cells were exposed to a pulsed electromagnetic field at various frequencies in order to determine which, if any, frequency would affect the TNF-NFkB-A20 inflammatory response pathway. Our study revealed that cells continuously exposed to a pulsed electromagnetic field at 5 Hz demonstrated significant changes in the downregulation of TNF-α and NFkB and also showed a trend in the down regulation of A20, as compared with controls. This treatment could be beneficial in modulating the immune response, in the presence of infection. Keyword: TNFAIP3, pulsed electromagnetic field, macrophages, TNF, NFkB

  19. Clinical update of pulsed electromagnetic fields on osteoporosis

    Institute of Scientific and Technical Information of China (English)

    HUANG Li-qun; HE Hong-chen; HE Cheng-qi; CHEN Jian; YANG Lin

    2008-01-01

    Objective To understand the effects of low-frequency pulsed electromagnetic fields (PEMFs) on chronic bony pain,bone mineral density (BMD), bone strength and biochemical markers of bone metabolism in the patients of osteoporosis.Data sources Using the key words "pulsed electromagnetic fields" and "osteoporosis", we searched the PubMed for related studies published in English from January 1996 to December 2007. We also searched the China National Knowledge Infrastructure (CNKI) for studies published in Chinese from January 1996 to December 2007.Study selection Inclusion criteria: (1) all articles which referred to the effects of low-frequency pulsed magnetic fields on osteoporosis either in primary osteoporosis or secondary osteoporosis; (2) either observational studies or randomized controlled studies. Exclusion criteria: (1) articles on experimental studies about osteoporosis; (2) repetitive studies; (3)case reports; (4) meta analysis.Results Totally 111 related articles were collected, 101 of them were published in Chinese, 10 were in English.Thirty-four were included and the remaining 84 were excluded.Conclusions Low-frequency PEMFs relieves the pain of primary osteoporosis quickly and efficiently, enhances bone formation and increases BMD of secondary osteoporosis. But the effects of PEMFs on bone mineral density of primary osteoporosis and bone resorption were controversial.

  20. Stopping Narrow-Band X-Ray Pulses in Nuclear Media

    Science.gov (United States)

    Kong, Xiangjin; Pálffy, Adriana

    2016-05-01

    A control mechanism for stopping x-ray pulses in resonant nuclear media is investigated theoretically. We show that narrow-band x-ray pulses can be mapped and stored as nuclear coherence in a thin-film planar x-ray cavity with an embedded 57Fe nuclear layer. The pulse is nearly resonant to the 14.4 keV Mössbauer transition in the 57Fe nuclei. The role of the control field is played here by a hyperfine magnetic field which induces interference effects reminiscent of electromagnetically induced transparency. We show that, by switching off the control magnetic field, a narrow-band x-ray pulse can be completely stored in the cavity for approximately 100 ns. Additional manipulation of the external magnetic field can lead to both group velocity and phase control of the pulse in the x-ray cavity sample.

  1. Numerical simulation of compact intracloud discharge and generated electromagnetic pulse

    Science.gov (United States)

    Babich, L. P.; Bochkov, E. I.; Kutsyk, I. M.

    2015-06-01

    Using the concept of the relativistic runaway electron avalanche, numerical simulation of compact intracloud discharge as a generator of powerful natural electromagnetic pulses (EMPs) in the HF-UHF range was conducted. We evaluated the numbers of electrons initiating the avalanche, with which the calculated EMP characteristics are consistent with measured ones. The discharge capable of generating EMPs produces runaway electrons in numbers close to those in the source of terrestrial γ-flashes (TGF) registered in the nearest space, which may be an argument for a joint EMP and TGF source.

  2. An online database of nuclear electromagnetic moments

    Science.gov (United States)

    Mertzimekis, T. J.; Stamou, K.; Psaltis, A.

    2016-01-01

    Measurements of nuclear magnetic dipole and electric quadrupole moments are considered quite important for the understanding of nuclear structure both near and far from the valley of stability. The recent advent of radioactive beams has resulted in a plethora of new, continuously flowing, experimental data on nuclear structure - including nuclear moments - which hinders the information management. A new, dedicated, public and user friendly online database

  3. Electromagnetic pulses produced by expanding laser-produced Au plasma

    Directory of Open Access Journals (Sweden)

    De Marco Massimo

    2015-06-01

    Full Text Available The interaction of an intense laser pulse with a solid target produces large number of fast free electrons. This emission gives rise to two distinct sources of the electromagnetic pulse (EMP: the pulsed return current through the holder of the target and the outflow of electrons into the vacuum. A relation between the characteristics of laser-produced plasma, the target return current and the EMP emission are presented in the case of a massive Au target irradiated with the intensity of up to 3 × 1016 W/cm2. The emission of the EMP was recorded using a 12 cm diameter Moebius loop antennas, and the target return current was measured using a new type of inductive target probe (T-probe. The simultaneous use of the inductive target probe and the Moebius loop antenna represents a new useful way of diagnosing the laser–matter interaction, which was employed to distinguish between laser-generated ion sources driven by low and high contrast laser pulses.

  4. Electrochemotherapy by pulsed electromagnetic field treatment (PEMF in mouse melanoma B16F10 in vivo

    Directory of Open Access Journals (Sweden)

    Kranjc Simona

    2016-03-01

    Full Text Available Pulsed electromagnetic field (PEMF induces pulsed electric field, which presumably increases membrane permeabilization of the exposed cells, similar to the conventional electroporation. Thus, contactless PEMF could represent a promising approach for drug delivery.

  5. An Approach for Effect Analysis of Electromagnetic Pulse in Operating NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Ho Sun; Ye, Song Hae; Kim, Minyi; Lee, Euijong [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    Recently, there is a growing Electromagnetic Pulse (EMP) threat caused by North Korea’s nuclear weapons and unmanned aerial vehicles (UAVs). KHNP CRI is currently conducting a research project that will evaluate the safety of domestic nuclear power plants (NPPs) against EMP effects and prepare safety measures to counter vulnerable points. We will instead use simulation tools to evaluate the electromagnetic shielding ability and the conductivity of cables through vulnerable points in NPPs. Through a study of electromagnetic simulation techniques and tools, this paper suggests a simulation method for analysis of EMP effects in operating NPPs. Although 3D tools are relatively accurate, is difficult to use only 3D tools to simulate EMP effects for huge and complex structures such as NPPs. It is more efficient in terms of cost and time to use a 3D tool and an EMT tool for the simulation of such structures. We have compared the advantages and disadvantages of various methods and have selected the most appropriate tools; we will proceed in our next paper with the simulation of EMP effects.

  6. Electromagnetic studies of nuclear structure and reactions

    Science.gov (United States)

    Hersman, F. W.; Dawson, J. F.; Heisenberg, J. H.; Calarco, J. R.

    1990-06-01

    This report contains papers on the following topics: giant resonance studies; deep inelastic scattering studies; high resolution nuclear structure work; and relativistic RPA; and field theory in the Schroedinger Representation.

  7. Qubit lattice coherence induced by electromagnetic pulses in superconducting metamaterials.

    Science.gov (United States)

    Ivić, Z; Lazarides, N; Tsironis, G P

    2016-07-12

    Quantum bits (qubits) are at the heart of quantum information processing schemes. Currently, solid-state qubits, and in particular the superconducting ones, seem to satisfy the requirements for being the building blocks of viable quantum computers, since they exhibit relatively long coherence times, extremely low dissipation, and scalability. The possibility of achieving quantum coherence in macroscopic circuits comprising Josephson junctions, envisioned by Legett in the 1980's, was demonstrated for the first time in a charge qubit; since then, the exploitation of macroscopic quantum effects in low-capacitance Josephson junction circuits allowed for the realization of several kinds of superconducting qubits. Furthermore, coupling between qubits has been successfully achieved that was followed by the construction of multiple-qubit logic gates and the implementation of several algorithms. Here it is demonstrated that induced qubit lattice coherence as well as two remarkable quantum coherent optical phenomena, i.e., self-induced transparency and Dicke-type superradiance, may occur during light-pulse propagation in quantum metamaterials comprising superconducting charge qubits. The generated qubit lattice pulse forms a compound "quantum breather" that propagates in synchrony with the electromagnetic pulse. The experimental confirmation of such effects in superconducting quantum metamaterials may open a new pathway to potentially powerful quantum computing.

  8. Qubit lattice coherence induced by electromagnetic pulses in superconducting metamaterials

    Science.gov (United States)

    Ivić, Z.; Lazarides, N.; Tsironis, G. P.

    2016-07-01

    Quantum bits (qubits) are at the heart of quantum information processing schemes. Currently, solid-state qubits, and in particular the superconducting ones, seem to satisfy the requirements for being the building blocks of viable quantum computers, since they exhibit relatively long coherence times, extremely low dissipation, and scalability. The possibility of achieving quantum coherence in macroscopic circuits comprising Josephson junctions, envisioned by Legett in the 1980’s, was demonstrated for the first time in a charge qubit; since then, the exploitation of macroscopic quantum effects in low-capacitance Josephson junction circuits allowed for the realization of several kinds of superconducting qubits. Furthermore, coupling between qubits has been successfully achieved that was followed by the construction of multiple-qubit logic gates and the implementation of several algorithms. Here it is demonstrated that induced qubit lattice coherence as well as two remarkable quantum coherent optical phenomena, i.e., self-induced transparency and Dicke-type superradiance, may occur during light-pulse propagation in quantum metamaterials comprising superconducting charge qubits. The generated qubit lattice pulse forms a compound ”quantum breather” that propagates in synchrony with the electromagnetic pulse. The experimental confirmation of such effects in superconducting quantum metamaterials may open a new pathway to potentially powerful quantum computing.

  9. Qubit lattice coherence induced by electromagnetic pulses in superconducting metamaterials

    Science.gov (United States)

    Ivić, Z.; Lazarides, N.; Tsironis, G. P.

    2016-01-01

    Quantum bits (qubits) are at the heart of quantum information processing schemes. Currently, solid-state qubits, and in particular the superconducting ones, seem to satisfy the requirements for being the building blocks of viable quantum computers, since they exhibit relatively long coherence times, extremely low dissipation, and scalability. The possibility of achieving quantum coherence in macroscopic circuits comprising Josephson junctions, envisioned by Legett in the 1980’s, was demonstrated for the first time in a charge qubit; since then, the exploitation of macroscopic quantum effects in low-capacitance Josephson junction circuits allowed for the realization of several kinds of superconducting qubits. Furthermore, coupling between qubits has been successfully achieved that was followed by the construction of multiple-qubit logic gates and the implementation of several algorithms. Here it is demonstrated that induced qubit lattice coherence as well as two remarkable quantum coherent optical phenomena, i.e., self-induced transparency and Dicke-type superradiance, may occur during light-pulse propagation in quantum metamaterials comprising superconducting charge qubits. The generated qubit lattice pulse forms a compound ”quantum breather” that propagates in synchrony with the electromagnetic pulse. The experimental confirmation of such effects in superconducting quantum metamaterials may open a new pathway to potentially powerful quantum computing. PMID:27403780

  10. Electromagnetic and nuclear radiation detector using micromechanical sensors

    Science.gov (United States)

    Thundat, Thomas G.; Warmack, Robert J.; Wachter, Eric A.

    2000-01-01

    Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.

  11. Electromagnetic pulse research on electric power systems: Program summary and recommendations. Power Systems Technology Program

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, P.R.; McConnell, B.W.; Van Dyke, J.W. [Oak Ridge National Lab., TN (United States); Tesche, F.M. [Tesche (F.M.), Dallas, TX (United States); Vance, E.F. [Vance (E.F.), Fort Worth, TX (United States)

    1993-01-01

    A single nuclear detonation several hundred kilometers above the central United States will subject much of the nation to a high-altitude electromagnetic pulse (BENT). This pulse consists of an intense steep-front, short-duration transient electromagnetic field, followed by a geomagnetic disturbance with tens of seconds duration. This latter environment is referred to as the magnetohydrodynamic electromagnetic pulse (NMENT). Both the early-time transient and the geomagnetic disturbance could impact the operation of the nation`s power systems. Since 1983, the US Department of Energy has been actively pursuing a research program to assess the potential impacts of one or more BENT events on the nation`s electric energy supply. This report summarizes the results of that program and provides recommendations for enhancing power system reliability under HENT conditions. A nominal HENP environment suitable for assessing geographically large systems was developed during the program and is briefly described in this report. This environment was used to provide a realistic indication of BEMP impacts on electric power systems. It was found that a single high-altitude burst, which could significantly disturb the geomagnetic field, may cause the interconnected power network to break up into utility islands with massive power failures in some areas. However, permanent damage would be isolated, and restoration should be possible within a few hours. Multiple bursts would likely increase the blackout areas, component failures, and restoration time. However, a long-term blackout of many months is unlikely because major power system components, such as transformers, are not likely to be damaged by the nominal HEND environment. Moreover, power system reliability, under both HENT and normal operating conditions, can be enhanced by simple, and often low cost, modifications to current utility practices.

  12. Electromagnetic pulse research on electric power systems: Program summary and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, P.R.; McConnell, B.W.; Van Dyke, J.W. (Oak Ridge National Lab., TN (United States)); Tesche, F.M. (Tesche (F.M.), Dallas, TX (United States)); Vance, E.F. (Vance (E.F.), Fort Worth, TX (United States))

    1993-01-01

    A single nuclear detonation several hundred kilometers above the central United States will subject much of the nation to a high-altitude electromagnetic pulse (BENT). This pulse consists of an intense steep-front, short-duration transient electromagnetic field, followed by a geomagnetic disturbance with tens of seconds duration. This latter environment is referred to as the magnetohydrodynamic electromagnetic pulse (NMENT). Both the early-time transient and the geomagnetic disturbance could impact the operation of the nation's power systems. Since 1983, the US Department of Energy has been actively pursuing a research program to assess the potential impacts of one or more BENT events on the nation's electric energy supply. This report summarizes the results of that program and provides recommendations for enhancing power system reliability under HENT conditions. A nominal HENP environment suitable for assessing geographically large systems was developed during the program and is briefly described in this report. This environment was used to provide a realistic indication of BEMP impacts on electric power systems. It was found that a single high-altitude burst, which could significantly disturb the geomagnetic field, may cause the interconnected power network to break up into utility islands with massive power failures in some areas. However, permanent damage would be isolated, and restoration should be possible within a few hours. Multiple bursts would likely increase the blackout areas, component failures, and restoration time. However, a long-term blackout of many months is unlikely because major power system components, such as transformers, are not likely to be damaged by the nominal HEND environment. Moreover, power system reliability, under both HENT and normal operating conditions, can be enhanced by simple, and often low cost, modifications to current utility practices.

  13. Electromagnetic pulse (EMP): Exposure of missile 56 in EMP simulator sapiens

    Science.gov (United States)

    Dikvall, T.

    1985-06-01

    The effects on the electric field caused by the object (missile) in the SAPIENS electromagnetic pulse simulator were studied. A noticeable effect on the field strength is noted close to the object, due to the characteristics of the field. This effect also appears in real electromagnetic pulse environments. During these tests 200 pulses were distributed with good accuracy of reproduction. The SAPIENS is an outdoor device and tests carried out in winter show that weather has very little influence on results.

  14. Locating voids beneath pavement using pulsed electromagnetic waves

    Science.gov (United States)

    Steinway, W. J.; Echard, J. D.; Luke, C. M.

    1981-11-01

    The feasibility of using pulsed electromagnetic wave technology for locating and sizing voids beneath reinforced and nonreinforced portland cement concrete pavements is determined. The data processing techniques developed can be implemented to provide information for void depth and sizing to + or - 1/2 in. and spatial location within + or - 6 in. A very short pulse radar directly connected to a microcomputer was chosen as the equipment necessary to obtain measurements. This equipment has the required accuracy and reliability, and is a cost effective solution for the void locating problem. The radar provides a signal return from voids that has unique characteristics that can be examined to provide information regarding the location, depth, and shape of the void. The microcomputer provides a means of real time processing to extract the information from the radar signal return and record the results. Theoretical modeling of signal returns from voids led to suitable techniques for locating and sizing voids beneath the pavement. Analysis and application of these techniques to radar measurements verified the theoretical predictions that radar can be used to determine the location, size, and shape of actual voids.

  15. Pulsed Dynamic Nuclear Polarization with Trityl Radicals.

    Science.gov (United States)

    Mathies, Guinevere; Jain, Sheetal; Reese, Marcel; Griffin, Robert G

    2016-01-07

    Continuous-wave (CW) dynamic nuclear polarization (DNP) is now established as a method of choice to enhance the sensitivity in a variety of NMR experiments. Nevertheless, there remains a need for the development of more efficient methods to transfer polarization from electrons to nuclei. Of particular interest are pulsed DNP methods because they enable a rapid and efficient polarization transfer that, in contrast with CW DNP methods, is not attenuated at high magnetic fields. Here we report nuclear spin orientation via electron spin-locking (NOVEL) experiments using the polarizing agent trityl OX063 in glycerol/water at a temperature of 80 K and a magnetic field of 0.34 T. (1)H NMR signal enhancements up to 430 are observed, and the buildup of the local polarization occurs in a few hundred nanoseconds. Thus, NOVEL can efficiently dynamically polarize (1)H atoms in a system that is of general interest to the solid-state DNP NMR community. This is a first, important step toward the general application of pulsed DNP at higher fields.

  16. Influence of electromagnetic signal of antibiotics excited by low-frequency pulsed electromagnetic fields on growth of Escherichia coli.

    Science.gov (United States)

    Ke, Yin-Lung; Chang, Fu-Yu; Chen, Ming-Kun; Li, Shun-Lai; Jang, Ling-Sheng

    2013-01-01

    Energy medicine (EM) provides a new medical choice for patients, and its advantages are the noninvasive detection and nondrug treatment. An electromagnetic signal, a kind of EM, induced from antibiotic coupling with weak, extremely low-frequency pulsed electromagnetic fields (PEMFs) is utilized for investigating the growth speed of Escherichia coli (E. coli). PEMFs are produced by solenoidal coils for coupling the electromagnetic signal of antibiotics (penicillin). The growth retardation rate (GRR) of E. coli is used to investigate the efficacy of the electromagnetic signal of antibiotics. The E. coli is cultivated in the exposure of PEMFs coupling with the electromagnetic signal of antibiotics. The maximum GRR of PEMFs with and without the electromagnetic signal of antibiotics on the growth of E. coli cells in the logarithmic is 17.4 and 9.08%, respectively. The electromagnetic signal of antibiotics is successfully coupled by the electromagnetic signal coupling instrument to affect the growth of E. coli. In addition, the retardation effect on E. coli growth can be improved of by changing the carrier frequency of PEMFs coupling with the electromagnetic signal of antibiotics. GRR caused by the electromagnetic signal of antibiotics can be fixed by a different carrier frequency in a different phase of E. coli growth.

  17. PERCEPTION LEVEL EVALUATION OF RADIO ELECTRONIC MEANS TO A PULSE OF ELECTROMAGNETIC RADIATION

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available The method for evaluating the perception level of electronic means to pulsed electromagnetic radiation is consid- ered in this article. The electromagnetic wave penetration mechanism towards the elements of electronic systems and the impact on them are determined by the intensity of the radiation field on the elements of electronic systems. The impact of electromagnetic radiation pulses to the electronic systems refers to physical and analytical parameters of the relationship between exposure to pulses of electromagnetic radiation and the sample parameters of electronic systems. A physical and mathematical model of evaluating the perception level of electronic means to pulsed electromagnetic radiation is given. The developed model was based on the physics of electronics means failure which represents the description of electro- magnetic, electric and thermal processes that lead to the degradation of the original structure of the apparatus elements. The conditions that lead to the total equation electronic systems functional destruction when exposed to electromagnetic radia- tion pulses are described. The internal characteristics of the component elements that respond to the damaging effects are considered. The ratio for the power failure is determined. A thermal breakdown temperature versus pulse duration of expo- sure at various power levels is obtained. The way of evaluation the reliability of electronic systems when exposed to pulses of electromagnetic radiation as a destructive factor is obtained.

  18. Effect of frequency variation on electromagnetic pulse interaction with charges and plasma

    NARCIS (Netherlands)

    Khachatryan, A.G.; Goor, van F.A.; Verschuur, J.W.J.; Boller, K.-J.

    2005-01-01

    The effect of frequency variation (chirp) in an electromagnetic (EM) pulse on the pulse interaction with a charged particle and plasma is studied. Various types of chirp and pulse envelopes are considered. In vacuum, a charged particle receives a kick in the polarization direction after interaction

  19. Susceptibility of personal computer systems to electromagnetic pulses with double exponential character

    Directory of Open Access Journals (Sweden)

    M. Camp

    2004-01-01

    Full Text Available In this paper the susceptibility of personal computer systems to fast transient electromagnetic pulses with double exponential pulse shapes (EMP, UWB is determined. The influence of the computer generation, RAM-values, different program states and the pulse shape, as well as the destruction thresholds of single PC-components (CPU, RAM, BIOS, Mainboard have been investigated.

  20. Nuclear electromagnetic charge and current operators in Chiral EFT

    Energy Technology Data Exchange (ETDEWEB)

    Girlanda, Luca [Università del Salento; Marcucci, Laura Elisa [Univ. Pisa; Pastore, Saori [Department of Physics and Astronomy, University of South Carolina, Columbia, SC; Piarulli, Maria [Department of Physics, Old Dominion University, Norfolk, VA; Schiavilla, Rocco [Old Dominion U., JLAB; Viviani, Michele

    2013-08-01

    We describe our method for deriving the nuclear electromagnetic charge and current operators in chiral perturbation theory, based on time-ordered perturbation theory. We then discuss possible strategies for fixing the relevant low-energy constants, from the magnetic moments of the deuteron and of the trinucleons, and from the radiative np capture cross sections, and identify a scheme which, partly relying on {Delta} resonance saturation, leads to a reasonable pattern of convergence of the chiral expansion.

  1. Low-intensity pulsed ultrasound (LIPUS) and pulsed electromagnetic field (PEMF) treatments affect degeneration of cultured articular cartilage explants

    NARCIS (Netherlands)

    Tan, Lijun; Ren, Yijin; Kooten, van Theo G.; Grijpma, Dirk W.; Kuijer, Roel

    2015-01-01

    Purpose: Articular cartilage has some capacity for self-repair. Clinically used low-intensity pulsed ultrasound (LIPUS) and pulsed electromagnetic field (PEMF) treatments were compared in their potency to prevent degeneration using an explant model of porcine cartilage. Methods: Explants of porcine

  2. Mitigation of Electromagnetic Pulse (EMP) Effects from Short-Pulse Lasers and Fusion Neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Eder, D C; Throop, A; Brown, Jr., C G; Kimbrough, J; Stowell, M L; White, D A; Song, P; Back, N; MacPhee, A; Chen, H; DeHope, W; Ping, Y; Maddox, B; Lister, J; Pratt, G; Ma, T; Tsui, Y; Perkins, M; O' Brien, D; Patel, P

    2009-03-06

    Our research focused on obtaining a fundamental understanding of the source and properties of EMP at the Titan PW(petawatt)-class laser facility. The project was motivated by data loss and damage to components due to EMP, which can limit diagnostic techniques that can be used reliably at short-pulse PW-class laser facilities. Our measurements of the electromagnetic fields, using a variety of probes, provide information on the strength, time duration, and frequency dependence of the EMP. We measure electric field strengths in the 100's of kV/m range, durations up to 100 ns, and very broad frequency response extending out to 5 GHz and possibly beyond. This information is being used to design shielding to mitigate the effects of EMP on components at various laser facilities. We showed the need for well-shielded cables and oscilloscopes to obtain high quality data. Significant work was invested in data analysis techniques to process this data. This work is now being transferred to data analysis procedures for the EMP diagnostics being fielded on the National Ignition Facility (NIF). In addition to electromagnetic field measurements, we measured the spatial and energy distribution of electrons escaping from targets. This information is used as input into the 3D electromagnetic code, EMSolve, which calculates time dependent electromagnetic fields. The simulation results compare reasonably well with data for both the strength and broad frequency bandwidth of the EMP. This modeling work required significant improvements in EMSolve to model the fields in the Titan chamber generated by electrons escaping the target. During dedicated Titan shots, we studied the effects of varying laser energy, target size, and pulse duration on EMP properties. We also studied the effect of surrounding the target with a thick conducting sphere and cube as a potential mitigation approach. System generated EMP (SGEMP) in coaxial cables does not appear to be a significant at Titan. Our

  3. Effects of electromagnetic pulse on serum element levels in rat.

    Science.gov (United States)

    Li, Kangchu; Ma, Shirong; Ren, Dongqing; Li, Yurong; Ding, Guirong; Liu, Junye; Guo, Yao; Guo, Guozhen

    2014-04-01

    Electromagnetic pulse (EMP) was a potentially harmful factor to the human body, and a biological dosimetry to evaluate effects of EMP is necessary. Little is known about effects of EMP on concentration of macro and trace elements in serum so far. In this study, Sprague-Dawley rats were randomly divided into 50-kV/m EMP-exposed group (n = 10), 100-kV/m EMP-exposed group (n = 10), 200-kV/m EMP-exposed group (n = 40), and the sham-exposed group (n = 20). The macro and trace element concentrations in serum were examined at 6, 12, 24, and 48 h after EMP exposure at different electric field intensities. Compared with the sham-exposed groups, the concentration of sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), zinc (Zn), copper (Cu), iron (Fe), selenium (Se), and manganese (Mn) in rat serum was not changed significantly within 48 h after 200 pulses of EMP exposure at electric field intensity of 50, 100, and 200 kV/m although the K level was decreased and the Ca level was increased with the electric field intensity of EMP increasing. In addition, there was a tendency that the Zn level was decreased with the time going on within 48 h after EMP exposure. Under our experimental conditions, EMP exposure cannot affect the concentration of macro and trace elements in rat serum. There was no time-effect or dose-effect relationship between EMP exposure and serum element levels. The macro and trace elements in serum are not suitable endpoints of biological dosimetry of EMP.

  4. The Effect of Ionospheric Models on Electromagnetic Pulse Locations

    Energy Technology Data Exchange (ETDEWEB)

    Fenimore, Edward E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Triplett, Laurie A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-07-01

    Locations of electromagnetic pulses (EMPs) determined by time-of-arrival (TOA) often have outliers with significantly larger errors than expected. In the past, these errors were thought to arise from high order terms in the Appleton-Hartree equation. We simulated 1000 events randomly spread around the Earth into a constellation of 22 GPS satellites. We used four different ionospheres: “simple” where the time delay goes as the inverse of the frequency-squared, “full Appleton-Hartree”, the “BobRD integrals” and a full raytracing code. The simple and full Appleton-Hartree ionospheres do not show outliers whereas the BobRD and raytracing do. This strongly suggests that the cause of the outliers is not additional terms in the Appleton-Hartree equation, but rather is due to the additional path length due to refraction. A method to fix the outliers is suggested based on fitting a time to the delays calculated at the 5 GPS frequencies with BobRD and simple ionospheres. The difference in time is used as a correction to the TOAs.

  5. Effects of pulsed electromagnetic fields on postmenopausal osteoporosis.

    Science.gov (United States)

    Zhu, Siyi; He, Hongchen; Zhang, Chi; Wang, Haiming; Gao, Chengfei; Yu, Xijie; He, Chengqi

    2017-09-01

    Postmenopausal osteoporosis (PMOP) is considered to be a well-defined subject that has caused high morbidity and mortality. In elderly women diagnosed with PMOP, low bone mass and fragile bone strength have been proven to significantly increase risk of fragility fractures. Currently, various anabolic and anti-resorptive therapies have been employed in an attempt to retain healthy bone mass and strength. Pulsed electromagnetic fields (PEMFs), first applied in treating patients with delayed fracture healing and nonunions, may turn out to be another potential and effective therapy for PMOP. PEMFs can enhance osteoblastogenesis and inhibit osteoclastogenesis, thus contributing to an increase in bone mass and strength. However, accurate mechanisms of the positive effects of PEMFs on PMOP remain to be further elucidated. This review attempts to summarize recent advances of PEMFs in treating PMOP based on clinical trials, and animal and cellular studies. Possible mechanisms are also introduced, and the future possibility of application of PEMFs on PMOP are further explored and discussed. Bioelectromagnetics. 38:406-424, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. In vitro exposure of human chondrocytes to pulsed electromagnetic fields

    Directory of Open Access Journals (Sweden)

    V Nicolin

    2009-08-01

    Full Text Available The effect of pulsed electromagnetic fields (PEMFs on the proliferation and survival of matrix-induced autologous chondrocyte implantation (MACI®-derived cells was studied to ascertain the healing potential of PEMFs. MACI-derived cells were taken from cartilage biopsies 6 months after surgery and cultured. No dedifferentiation towards the fibroblastic phenotype occurred, indicating the success of the surgical implantation. The MACI-derived cultured chondrocytes were exposed to 12 h/day (short term or 4 h/day (long term PEMFs exposure (magnetic field intensity, 2 mT; frequency, 75 Hz and proliferation rate determined by flow cytometric analysis. The PEMFs exposure elicited a significant increase of cell number in the SG2M cell cycle phase. Moreover, cells isolated from MACI® scaffolds showed the presence of collagen type II, a typical marker of chondrocyte functionality. The results show that MACI® membranes represent an optimal bioengineering device to support chondrocyte growth and proliferation in surgical implants. The surgical implant of MACI® combined with physiotherapy is suggested as a promising approach for a faster and safer treatment of cartilage traumatic lesions.

  7. Electromagnetic pulse (EMP) survey of the FEMA Region X Federal Regional Center, Bothell, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Crutcher, R.I.; Buchanan, M.E.; Jones, R.W.

    1991-11-01

    The purpose of this report is to develop an engineering design package to protect the Federal Emergency Management Agency (FEMA) National Radio System (FNARS) facilities against the effects of high-altitude electromagnetic pulses (HEMPS). This report refers to the FEMA Federal Regional Center (FRC) in Bothell, Washington. It is highly probably that there will be a heavy dependence upon high-frequency (hf) radio communications for long-haul communications following a nuclear attack on the continental United States, should one occur. To maintain the viability of the FEMA hf radio network during such a situation, the FNARS facilities must take measures to protect against the effects of HEMP that are likely to be created in a nuclear confrontation. The equipment under stress has already been designed and built so that little opportunity exists for equipment design changes that could raise the threshold levels at which malfunctions occur. The solution must then be to reduce HEMP-induced stresses on the system by means of tailored retrofit hardening measures using commercial protection devices when available. If is the intent of this report to define the particular hardening measures that will minimize the susceptibility of the network components to HEMP effects. To the extent economically viable, protective actions have been recommended for implementation, along with necessary changes or additions, during the period of the FNARS upgrade program. This report addresses electromagnetic pulse (EMP) effects only, and disregards any condition in which radiation effects may be a factor. This report identifies the systems in the facility considered critical for emergency option. To identify the critical systems in the facility and the EMP coupling paths into these systems, an EMP survey of the facility was conducted. Results of the survey are presented along with recommendations for tailored retrofit hardening measures to be implemented to protect the facility from EMP.

  8. Strategies, Protections and Mitigations for Electric Grid from Electromagnetic Pulse Effects

    Energy Technology Data Exchange (ETDEWEB)

    Foster, Rita Ann [Idaho National Lab. (INL), Idaho Falls, ID (United States); Frickey, Steven Jay [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-01-01

    The mission of DOE’s Office of Electricity Delivery and Energy Reliability (OE) is to lead national efforts to modernize the electricity delivery system, enhance the security and reliability of America’s energy infrastructure and facilitate recovery from disruptions to the energy supply. One of the threats OE is concerned about is a high-altitude electro-magnetic pulse (HEMP) from a nuclear explosion and eletro-magnetic pulse (EMP) or E1 pulse can be generated by EMP weapons. DOE-OE provides federal leadership and technical guidance in addressing electric grid issues. The Idaho National Laboratory (INL) was chosen to conduct the EMP study for DOE-OE due to its capabilities and experience in setting up EMP experiments on the electric grid and conducting vulnerability assessments and developing innovative technology to increase infrastructure resiliency. This report identifies known impacts to EMP threats, known mitigations and effectiveness of mitigations, potential cost of mitigation, areas for government and private partnerships in protecting the electric grid to EMP, and identifying gaps in our knowledge and protection strategies.

  9. Strategies, Protections and Mitigations for Electric Grid Affets from Electro-Magnetic Pulse

    Energy Technology Data Exchange (ETDEWEB)

    Foster, Rita Ann [Idaho National Lab. (INL), Idaho Falls, ID (United States); Frickey, Steven Jay [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-01-01

    The mission of DOE’s Office of Electricity Delivery and Energy Reliability (OE) is to lead national efforts to modernize the electricity delivery system, enhance the security and reliability of America’s energy infrastructure and facilitate recovery from disruptions to the energy supply. One of the threats OE is concerned about is a high-altitude electro-magnetic pulse (HEMP) from a nuclear explosion and eletro-magnetic pulse (EMP) or E1 pulse can be generated by EMP weapons. DOE-OE provides federal leadership and technical guidance in addressing electric grid issues. The Idaho National Laboratory (INL) was chosen to conduct the EMP study for DOE-OE due to its capabilities and experience in setting up EMP experiments on the electric grid and conducting vulnerability assessments and developing innovative technology to increase infrastructure resiliency. This report identifies known impacts to EMP threats, known mitigations and effectiveness of mitigations, potential cost of mitigation, areas for government and private partnerships in protecting the electric grid to EMP, and identifying gaps in our knowledge and protection strategies.

  10. THE INFLUENCE OF NANOSECOND ELECTROMAGNETIC PULSES TO OBTAIN TIN AND THE PROPERTIES OF ITS ALLOYS

    Directory of Open Access Journals (Sweden)

    V. G. Komkov

    2012-01-01

    Full Text Available Experimentally found that the effect of nanosecond electromagnetic pulses to melt the charge, while the carbon thermal recovery of the tin ore, accelerates the formation of the metallic phase.

  11. Experimental study and mechanism analysis on bioeffects by nanosecond electromagnetic pulses

    Institute of Scientific and Technical Information of China (English)

    王保义; 杨杰斌; 郭庆功; 徐润民; 刘长军; 张弘; 邹方东; 王子淑

    1997-01-01

    The athermal bioeffects caused by nanosecond electromagnetic pulses with body cells was studied by using a broad band transverse EM-wave cell (BTEM CELL). The experimental system and preliminary mechanism analysis were presented.

  12. Direct space-time observation of pulse tunneling in an electromagnetic band gap

    Science.gov (United States)

    Doiron, Serge; Haché, Alain; Winful, Herbert G.

    2007-08-01

    We present space-time-resolved measurements of electromagnetic pulses tunneling through a coaxial electromagnetic band gap structure. The results show that during the tunneling process the field distribution inside the barrier is an exponentially decaying standing wave whose amplitude increases and decreases as it slowly follows the temporal evolution of the input pulse. At no time is a pulse maximum found inside the barrier, and hence the transmitted peak is not the incident peak that has propagated to the exit. The results support the quasistatic interpretation of tunneling dynamics and confirm that the group delay is not the traversal time of the input pulse peak.

  13. Damage assessment of long-range rocket system by electromagnetic pulse weapon

    Science.gov (United States)

    Cao, Lingyu; Liu, Guoqing; Li, Jinming

    2017-08-01

    This paper analyzes the damage mechanism and characteristics of electromagnetic pulse weapon, establishes the index system of survivability of long-range rocket launcher system, and uses AHP method to establish the combat effectiveness model of long-range rocket missile system. According to the damage mechanism and characteristics of electromagnetic pulse weapon, the damage effect of the remote rocket system is established by using the exponential method to realize the damage efficiency of the remote rocket system.

  14. A new online database of nuclear electromagnetic moments

    Science.gov (United States)

    Mertzimekis, Theo J.

    2017-09-01

    Nuclear electromagnetic (EM) moments, i.e., the magnetic dipole and the electric quadrupole moments, provide important information of nuclear structure. As in other types of experimental data available to the community, measurements of nuclear EM moments have been organized systematically in compilations since the dawn of nuclear science. However, the wealth of recent moments measurements with radioactive beams, as well as earlier existing measurements, lack an online, easy-to-access, systematically organized presence to disseminate information to researchers. In addition, available printed compilations suffer a rather long life cycle, being left behind experimental measurements published in journals or elsewhere. A new, online database (http://magneticmoments.info">http://magneticmoments.info) focusing on nuclear EM moments has been recently developed to disseminate experimental data to the community. The database includes non-evaluated experimental data of nuclear EM moments, giving strong emphasis on frequent updates (life cycle is 3 months) and direct connection to the sources via DOI and NSR hyperlinks. It has been recently integrated in IAEA LiveChart [1], but can also be found as a standalone webapp [2]. A detailed review of the database features, as well as plans for further development and expansion in the near future is discussed.

  15. Giant elves: Lightning-generated electromagnetic pulses in giant planets.

    Science.gov (United States)

    Luque Estepa, Alejandro; Dubrovin, Daria; José Gordillo-Vázquez, Francisco; Ebert, Ute; Parra-Rojas, Francisco Carlos; Yair, Yoav; Price, Colin

    2015-04-01

    We currently have direct optical observations of atmospheric electricity in the two giant gaseous planets of our Solar System [1-5] as well as radio signatures that are possibly generated by lightning from the two icy planets Uranus and Neptune [6,7]. On Earth, the electrical activity of the troposphere is associated with secondary electrical phenomena called Transient Luminous Events (TLEs) that occur in the mesosphere and lower ionosphere. This led some researchers to ask if similar processes may also exist in other planets, focusing first on the quasi-static coupling mechanism [8], which on Earth is responsible for halos and sprites and then including also the induction field, which is negligible in our planet but dominant in Saturn [9]. However, one can show that, according to the best available estimation for lightning parameters, in giant planets such as Saturn and Jupiter the effect of the electromagnetic pulse (EMP) dominates the effect that a lightning discharge has on the lower ionosphere above it. Using a Finite-Differences, Time-Domain (FDTD) solver for the EMP we found [10] that electrically active storms may create a localized but long-lasting layer of enhanced ionization of up to 103 cm-3 free electrons below the ionosphere, thus extending the ionosphere downward. We also estimate that the electromagnetic pulse transports 107 J to 1010 J toward the ionosphere. There emissions of light of up to 108 J would create a transient luminous event analogous to a terrestrial elve. Although these emissions are about 10 times fainter than the emissions coming from the lightning itself, it may be possible to target them for detection by filtering the appropiate wavelengths. [1] Cook, A. F., II, T. C. Duxbury, and G. E. Hunt (1979), First results on Jovian lightning, Nature, 280, 794, doi:10.1038/280794a0. [2] Little, B., C. D. Anger, A. P. Ingersoll, A. R. Vasavada, D. A. Senske, H. H. Breneman, W. J. Borucki, and The Galileo SSI Team (1999), Galileo images of

  16. Light nuclear charge measurement with Alpha Magnetic Spectrometer Electromagnetic Calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Basara, Laurent [Trento Institute for Fundamental Physics and Applications, Povo 38123 (Italy); Choutko, Vitaly [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Li, Qiang, E-mail: q.li@cern.ch [Harbin Institute of Technology, Harbin, 150001 (China)

    2016-06-11

    The Alpha Magnetic Spectrometer (AMS) is a high energy particle detector installed and operating on board of the International Space Station (ISS) since May 2011. So far more than 70 billion cosmic ray events have been recorded by AMS. In the present paper the Electromagnetic Calorimeter (ECAL) detector of AMS is used to measure cosmic ray nuclear charge magnitudes up to Z=10. The obtained charge magnitude resolution is about 0.1 and 0.3 charge unit for Helium and Carbon, respectively. These measurements are important for an accurate determination of the interaction probabilities of various nuclei with the AMS materials. The ECAL charge calibration and measurement procedures are presented.

  17. 7th conference on ultra-wideband, short-pulse electromagnetics

    CERN Document Server

    Schenk, Uwe; Nitsch, Daniel; Sabath, Frank; Ultra-Wideband, Short-Pulse Electromagnetics 7; UWBSP7

    2007-01-01

    Ultra-wideband (UWB), short-pulse (SP) electromagnetics are now being used for an increasingly wide variety of applications, including collision avoidance radar, concealed object detection, and communications. Notable progress in UWB and SP technologies has been achieved by investigations of their theoretical bases and improvements in solid-state manufacturing, computers, and digitizers. UWB radar systems are also being used for mine clearing, oil pipeline inspections, archeology, geology, and electronic effects testing. Ultra-Wideband Short-Pulse Electromagnetics 7 presents selected papers of deep technical content and high scientific quality from the UWB-SP7 Conference, including wide-ranging contributions on electromagnetic theory, scattering, UWB antennas, UWB systems, ground penetrating radar (GPR), UWB communications, pulsed-power generation, time-domain computational electromagnetics, UWB compatibility, target detection and discrimination, propagation through dispersive media, and wavelet and multi-res...

  18. Pulsed electromagnetic field radiation from a narrow slot antenna with a dielectric layer

    NARCIS (Netherlands)

    Štumpf, M.; De Hoop, A.T.; Lager, I.E.

    2010-01-01

    Analytic time domain expressions are derived for the pulsed electromagnetic field radiated by a narrow slot antenna with a dielectric layer in a two‐dimensional model configuration. In any finite time window of observation, exact pulse shapes for the propagated, reflected, and refracted wave constit

  19. 8th conference on Ultra-Wideband Short-Pulse Electromagnetics

    CERN Document Server

    Tyo, J. Scott; Baum, Carl E; Ultra-Wideband Short-Pulse Electromagnetics 8; UWBSP8

    2007-01-01

    The purpose of the Ultra-Wideband Short-Pulse Electromagnetics Conference series is to focus on advanced technologies for the generation, radiation and detection of ultra-wideband short pulse signals, taking into account their propagation and scattering from and coupling to targets of interest. This Conference series reports on developments in supporting mathematical and numerical methods and presents current and potential future applications of the technology. Ultra-Wideband Short-Pulse Electromagnetics 8 is based on the American Electromagnetics 2006 conference held from June 3-7 in Albuquerque, New Mexico. Topical areas covered in this volume include pulse radiation and measurement, scattering theory, target detection and identification, antennas, signal processing, and communications.

  20. Influence of Turbulent Atmosphere on Polarization Properties of Stochastic Electromagnetic Pulsed Beams

    Institute of Scientific and Technical Information of China (English)

    DING Chao-Liang; ZHAO Zhi-Guo; LI Xiao-Feng; PAN Liu-Zhan; YUAN Xiao

    2011-01-01

    Using the coherence theory of non-stationary fields and the characterization of stochastic electromagnetic pulsed beams, the analytical expression for the spectral degree of polarization of stochastic electromagnetic Gaussian Schell-model pulsed (GSMP) beams in turbulent atmosphere is derived and is used to study the polarization properties of stochastic electromagnetic GSMP beams propagating through turbulent atmosphere. The results of numerical calculation are given to illustrate the dependence of spectral degree of polarization on the pulse frequency, refraction index structure constant and spatial correlation length. It is shown that, compared with free-space case, in turbulent atmosphere propagation there are two positions at which the on-axis spectral degree of polarization P is equal to zero. The position change depends on the pulse frequency, refraction index structure constant and spatial correlation length.%@@ Using the coherence theory of non-stationary fields and the characterization of stochastic electromagnetic pulsed beams, the analytical expression for the spectral degree of polarization of stochastic electromagnetic Gaussian Schell-model pulsed (GSMP) beams in turbulent atmosphere is derived and is used to study the polarization properties of stochastic electromagnetic GSMP beams propagating through turbulent atmosphere.The results of numerical calculation are given to illustrate the dependence of spectral degree of polarization on the pulse frequency, refraction index structure constant and spatial correlation length.It is shown that, compared with free-space case, in turbulent atmosphere propagation there are two positions at which the on-axis spectral degree of polarization P is equal to zero.The position change depends on the pulse frequency, refraction index structure constant and spatial correlation length.

  1. Pulsed electron-nuclear-electron triple resonance spectroscopy

    Science.gov (United States)

    Thomann, Hans; Bernardo, Marcelino

    1990-05-01

    A new experimental technique, pulsed electron-nuclear-electron triple resonance spectroscopy, is demonstrated. It is based on a modification of the pulse sequence for electron-nuclear double resonance (ENDOR) in which two EPR and one NMR transition are irradiated. The irradiation of one EPR transition is detected via a second EPR transition. The nuclear hyperfine coupling, which separates these EPR transition frequencies, is the irradiated NMR transition. The major advantages of triple resonance spectroscopy include the ability to resolve overlapping nuclear resonances in the ENDOR spectrum and a more direct quantitative assignment of nuclear hyperfine and quadrupole couplings. The triple resonance experiment is an alternative to the recently proposed method of employing rapid magnetic field jumps between microwave pulses for generating hyperfine selective ENDOR spectra.

  2. Optoelectronics Generation and Detection of Intense Terahertz Electromagnetic Pulses.

    Science.gov (United States)

    2007-11-02

    GaAs p-i-n diodes 19 C. Study of the physical mechanism of THz generation in bulk GaAs 19 D. Observation of Gunn Oscillation by triggering a vertical... Gunn diode with 25 femtosecond optical pulses IV. Tunable narrowband THz radiation 26 A. Chirped pulse beating 27 1. Optical cross-correlation...appropriately biased vertical transferred electron device ( Gunn diode ) with femtosecond optical pulses. " Investigation of the dynamics of photoinjected

  3. Electromagnetic Pulse Weapons as an Emergent Technology and Their Place on Battlefields of the Future

    Science.gov (United States)

    2010-04-19

    relationship of target’s hardening with respect to the generated electromagnetic pulse strength, electromagnetic atmospherics, and the electronic...Here targeting analysis becomes marked more complex and needs to encompass neighboring population centers which may be codependent on power or water...How is there relationship here at all? At first glance, it may seem absurd to consider an EMP a weapon of mass destruction. If improperly employed

  4. 10th and 11th conference on Ultra-Wideband Short-Pulse Electromagnetics

    CERN Document Server

    Mokole, Eric; UWB SP 10; UWB SP 11

    2014-01-01

    This book presents contributions of deep technical content and high scientific quality in the areas of electromagnetic theory, scattering, UWB antennas, UWB systems, ground penetrating radar (GPR), UWB communications, pulsed-power generation, time-domain computational electromagnetics, UWB compatibility, target detection and discrimination, propagation through dispersive media, and wavelet and multi-resolution techniques. Ultra-wideband (UWB), short-pulse (SP) electromagnetics are now being used for an increasingly wide variety of applications, including collision avoidance radar, concealed object detection, and communications. Notable progress in UWB and SP technologies has been achieved by investigations of their theoretical bases and improvements in solid-state manufacturing, computers, and digitizers. UWB radar systems are also being used for mine clearing, oil pipeline inspections, archeology, geology, and electronic effects testing. Like previous books in this series, Ultra-Wideband Short-Pulse Electrom...

  5. Pulse Design in Solid-State Nuclear Magnetic Resonance

    DEFF Research Database (Denmark)

    Palani, Ravi Shankar

    2017-01-01

    The work presented in this dissertation is centred on the theory of experimental methods in solid-state Nuclear Magnetic Resonance (NMR) spectroscopy, which deals with interaction of electromagnetic radiation with nuclei in a magnetic field and possessing a fundamental quantum mechanical property...

  6. Propagation of an ultrashort electromagnetic pulse in solid-state plasma

    CERN Document Server

    Astapenko, V A

    2013-01-01

    The change of the shape of an ultrashort electromagnetic pulse in its propagation in solid-state plasma was calculated in the linear approximation. A case of solid-state silver plasma and of a "Mexican hat" wavelet pulse was considered. The dielectric permittivity of the medium was calculated in the Drude model. Strong dispersion spreading of a pulse at distances of the order of several microns was shown, and the comparison of evolution of the pulse shape for different center frequencies was carried out.

  7. Focused electromagnetic doughnut pulses and their interaction with interfaces and nanostructures.

    Science.gov (United States)

    Raybould, Tim; Fedotov, Vassili; Papasimakis, Nikitas; Youngs, Ian; Zheludev, Nikolay

    2016-02-22

    "The "focused doughnut", a single-cycle electromagnetic perturbation of toroidal topology with inseparable time and spatial dependencies propagates at the speed of light in vacuum, as was shown by Hellwarth and Nouchi in 1996. While normal incidence reflection and refraction of conventional electromagnetic pulses in isotropic media do not lead to polarization changes, "focused doughnut" pulses undergo complex field transformations owing to the toroidal field structure and the presence of longitudinal components. We also demonstrate that "focused doughnuts" can interact strongly with structured media exciting dominant dynamic toroidal dipoles in spherical dielectric particles."

  8. Measurement of high-power microwave pulse under intense electromagnetic noise

    Indian Academy of Sciences (India)

    Amitava Roy; S K Singh; R Menon; D Senthil Kumar; R Venkateswaran; M R Kulkarni; P C Saroj; K V Nagesh; K C Mittal; D P Chakravarthy

    2010-01-01

    KALI-1000 pulse power system has been used to generate single pulse nanosecond duration high-power microwaves (HPM) from a virtual cathode oscillator (VIRCATOR) device. HPM power measurements were carried out using a transmitting–receiving system in the presence of intense high frequency (a few MHz) electromagnetic noise. Initially, the diode detector output signal could not be recorded due to the high noise level persisting in the ambiance. It was found that the HPM pulse can be successfully detected using wide band antenna, RF cable and diode detector set-up in the presence of significant electromagnetic noise. Estimated microwave peak power was ∼ 59.8 dBm (∼ 1 kW) at 7 m distance from the VIRCATOR window. Peak amplitude of the HPM signal varies on shot-to-shot basis. Duration of the HPM pulse (FWHM) also varies from 52 ns to 94 ns for different shots.

  9. Focused electromagnetic doughnut pulses and their interaction with interfaces and nanostructures

    CERN Document Server

    Raybould, T A; Papasimakis, N; Youngs, I J; Zheludev, N I

    2015-01-01

    We study the propagation properties and light-matter interactions of the focused doughnut pulses, broadband, single-cycle electromagnetic perturbations of toroidal topology first described by Hellwarth and Nouchi in 1996. We show how focused doughnuts are reflected and refracted at planar metallic and vacuum-dielectric interfaces leading to complex distortions of the field structure. We also identify the conditions under which these toroidal pulses excite dominant dynamic toroidal dipoles in spherical dielectric particles.

  10. Analysis of electromagnetic pulse (EMP measurements in the National Ignition Facility's target bay and chamber

    Directory of Open Access Journals (Sweden)

    Brown C.G.

    2013-11-01

    Full Text Available From May 2009 to the present we have recorded electromagnetic pulse (EMP strength and spectrum (100 MHz – 5 GHz in the target bay and chamber of the National Ignition Facility (NIF. The dependence of EMP strength and frequency spectrum on target type and laser energy is discussed. The largest EMP measured was for relatively low-energy, short-pulse (100 ps flat targets.

  11. Atomic Interferometry with Detuned Counter-Propagating Electromagnetic Pulses

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Ming -Yee [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-09-05

    Atomic fountain interferometry uses atoms cooled with optical molasses to 1 μK, which are then launched in a fountain mode. The interferometer relies on the nonlinear Raman interaction of counter-propagating visible light pulses. We present models of these key transitions through a series of Hamiltonians. Our models, which have been verified against special cases with known solutions, allow us to incorporate the effects of non-ideal pulse shapes and realistic laser frequency or wavevector jitter.

  12. Did high-altitude EMP (electromagnetic pulse) cause the Hawaiian streetlight incident

    Energy Technology Data Exchange (ETDEWEB)

    Vittitoe, C N

    1989-04-01

    Studies of electromagnetic pulse (EMP) effects on civilian and military systems predict results ranging from severe destruction to no damage. Convincing analyses that support either extreme are rare. The Hawaiian streetlight incident associated with the Starfish nuclear burst is the most widely quoted observed damage. We review the streetlight characteristics and estimate the coupling between the Starfish EMP and a particular streetlight circuit identified as one of the few that failed. Evidence indicates that the damage was EMP-generated. The main contributing factors were the azimuthal angle of the circuit relative to the direction of EMP propagation, and the rapid rise of the EMP signal. The azimuthal angle provided coherent buildup of voltage as the EMP swept across the transmission line. The rapid rise allowed substantial excitation before the canceling effects of ground reflections limited the signals. Resulting voltages were at the threshold for causing the observed fuse damage and are consistent with this damage occurring in only some of the strings in the systems. 15 refs., 16 figs., 4 tabs.

  13. Observation of Electromagnetically Induced Transparency by a Train of Short Pulses

    Institute of Scientific and Technical Information of China (English)

    YE Cun-Yun

    2004-01-01

    @@ We report the experimental demonstration of electromagnetically induced transparency in hot rubidium (85 Rb)atomic vapour by using an actively mode-locked external cavity diode laser in Littman-Metcalf configuration.We can make opaque resonant transitions transparent to any two optical comb components in the pulse trains which excite atomic coherence in the ground states of 85Rb.

  14. Field test and theoretical analysis of electromagnetic pulse propagation velocity on crossbonded cable systems

    DEFF Research Database (Denmark)

    Jensen, Christian Flytkjær; Bak, Claus Leth; Gudmundsdottir, Unnur Stella

    2014-01-01

    In this paper, the electromagnetic pulse propagation velocity on a three-phase cable system, consisting of three single core (SC) cables in flat formation with an earth continuity conductor is under study. The propagation velocity is an important parameter for most travelling wave off- and online...

  15. Transcranial low voltage pulsed electromagnetic fields in patients with treatment-resistant depression

    DEFF Research Database (Denmark)

    Martiny, Klaus Per Juul; Lunde, Marianne; Bech, Per

    2010-01-01

    of a new principle using low-intensity transcranially applied pulsed electromagnetic fields (T-PEMF) in combination with antidepressants in patients with treatment-resistant depression. METHODS: This was a sham-controlled double-blind study comparing 5 weeks of active or sham T-PEMF in patients...

  16. [Effect of pulsed electromagnetic field on orthodontic tooth movement through transmission electromicroscopy].

    Science.gov (United States)

    Chen, Q

    1991-01-01

    This experiment is to observe the effect of pulsed electromagnetic field (PEMF) on orthodontic tooth movement of guinea pigs through transmission electron microscope (TEM). 14-days observations indicate that PEMF could accelerate the rate of orthodontic tooth movement as a result of the increase in quantity of active cell without changing the ultrastructures of cells and have no unfavorable effects on periodontal tissues.

  17. analysis of large electromagnetic pulse simulators using the electric field integral equation method in time domain

    CERN Document Server

    Jamali, J; Moini, R; Sadeghi, H

    2002-01-01

    A time-domain approach is presented to calculate electromagnetic fields inside a large Electromagnetic Pulse (EMP) simulator. This type of EMP simulator is used for studying the effect of electromagnetic pulses on electrical apparatus in various structures such as vehicles, a reoplanes, etc. The simulator consists of three planar transmission lines. To solve the problem, we first model the metallic structure of the simulator as a grid of conducting wires. The numerical solution of the governing electric field integral equation is then obtained using the method of moments in time domain. To demonstrate the accuracy of the model, we consider a typical EMP simulator. The comparison of our results with those obtained experimentally in the literature validates the model introduced in this paper.

  18. Generation of powerful ultrashort electromagnetic pulses based on superradiance

    CERN Document Server

    Ginzburg, N S; Novozhilova, Y V; Sergeev, A S; Phelps, A D R; Cross, A W; Wiggins, S M; Ronald, K; Shpak, V G; Yalandin, M I; Shunailov, S A; Ulmaskulov, M R

    2001-01-01

    Experimental results of the observation of superradiation from intense, subnanosecond electron bunches moving through a periodic waveguide and interacting with a backward propagating TM sub 0 sub 1 wave are presented. The ultra-short microwave pulses in Ka, W, and G band were generated with repetition frequencies of up to 25 Hz. Observation of RF breakdown of ambient air, as well as direct measurements by hot-carrier germanium detectors, leads to an estimate of the peak power as high as 60-120 MW for the 300-400 ps pulses at 38 GHz. The initial observation of 75 GHz 10-15 MW radiation pulses with duration less than 150 ps, and of 150 GHz microwave spikes with a risetime of 75ps are also reported. Comparison with simulations is discussed as well.

  19. An Optimization of Pulsed ElectroMagnetic Fields Study

    Science.gov (United States)

    Goodwin, Thomas J.

    2006-01-01

    To date, in our research we have focused on the use of normal human neuronal progenitor (NHNP) cells because of their importance in human nervous system regeneration, development and maintenance, but we have developed 2-D and 3-D bioreactors that can accommodate any cell line. In this Project, we will include the use of tissues important for physiological regeneration: Human osteoblasts or chondrocytes, and vascular cells. Our initial results with the NHNP cells were quite startling using extremely low-level electromagnetic fields (5 microtesla at 10Hz; 6mA). The low-amplitude, rapidly time-varying electromagnetic fields exert a very potent effect on the proliferation, morphology, and gene expression of the cells in culture, both in standard 2-dimensional culture plates as well as cells organized into 3-dimensional tissue-like assemblies (TLAs) in a 3D bioreactor. We have replicated our preliminary results many, many times, have analyzed the gene expression using gene arrays (followed by Luminex analysis for protein production), and have monitored cell proliferation, orientation, morphology, and glucose metabolism, and we are confident that we have a stable and reliable model to study the control of high-level cellular processes by application of low-amplitude, time varying electromagnetic fields (TVEMF) (1, 2). In additional studies at the University of Michigan, we have been able to generate functional in vitro engineered mammalian skeletal muscle, and have employed nerve-muscle co-culture techniques to promote axonal sprouting. We believe that nearly all tissues, in particular, neural, are susceptible to the influences of low-level TVEMF.

  20. Development of electromagnetic welding facility of flat plates for nuclear industry

    Science.gov (United States)

    Kumar, Rajesh; Sahoo, Subhanarayan; Sarkar, Biswanath; Shyam, Anurag

    2017-04-01

    Electromagnetic pulse welding (EMPW) process, one of high speed welding process uses electromagnetic force from discharged current through working coil, which develops a repulsive force between the induced current flowing parallel and in opposite direction. For achieving the successful weldment using this process the design of working coil is the most important factor due to high magnetic field on surface of work piece. In case of high quality flat plate welding factors such as impact velocity, angle of impact standoff distance, thickness of flyer and overlap length have to be chosen carefully. EMPW has wide applications in nuclear industry, automotive industry, aerospace, electrical industries. However formability and weldability still remain major issues. Due to ease in controlling the magnetic field enveloped inside tubes, the EMPW has been widely used for tube welding. In case of flat components control of magnetic field is difficult. Hence the application of EMPW gets restricted. The present work attempts to make a novel contribution by investigating the effect of process parameters on welding quality of flat plates. The work emphasizes the approaches and engineering calculations required to effectively use of actuator in EMPW of flat components.

  1. High Dynamic Range Electric Field Sensor for Electromagnetic Pulse Detection

    CERN Document Server

    Lin, Che-Yun; Lee, Beom Suk; Zhang, Xingyu; Chen, Ray T

    2014-01-01

    We design a high dynamic range electric field sensor based on domain inverted electro-optic (E-O) polymer Y-fed directional coupler for electromagnetic wave detection. This electrode-less, all optical, wideband electrical field sensor is fabricated using standard processing for E-O polymer photonic devices. Experimental results demonstrate effective detection of electric field from 16.7V/m to 750KV/m at a frequency of 1GHz, and spurious free measurement range of 70dB.

  2. Protection of Medical Equipment against Electromagnetic Pulse (EMP): phase I

    Science.gov (United States)

    1986-06-12

    characteriitic associated with a typical EMP pin threat. This pin threat can be s ecified either as a damped sine wave or a rectangular pulse having a short ...Spectrophotometer, Stasar ............................... 77 7.12 Opthalmic Diathermy , TR 3000 ........................... 80 7.13 Birtcher 771 Micro...Opthalmic Diathermy TR 3000 ............................................. 82 7.12b Opthalmic Diathermy TR 3000 ................................... 83 7.13

  3. Interactions of Low-Frequency, Pulsed Electromagnetic Fields with Living Tissue: Biochemical Responses and Clinical Results

    DEFF Research Database (Denmark)

    Rahbek, Ulrik L.; Tritsaris, Katerina; Dissing, Steen

    2005-01-01

    In recent years many studies have demonstrated stimulatory effects of pulsed electromagnetic fields (PEMF) on biological tissue. However, controversies have also surrounded the research often due to the lack of knowledge of the different physical consequences of static versus pulsed electromagnetic...... fields. PEMF is widely used for treating fractures and non-unions as well as for treating diseases of the joints. Furthermore, new research has suggested that the technology can be used for nerve regeneration and wound healing although conclusive clinical trials, besides those for fracture healing......, are still lacking. Despite the apparent success of the PEMF technology very little is known regarding the coupling between pulsed electrical fields and biochemical events leading to cellular responses. Insight into this research area is therefore of great importance. In this review we describe the physical...

  4. Experimental and Theoretical Investigation of Directional Wideband Electromagnetic Pulse Photoemission Generator

    Science.gov (United States)

    Petrov, P. V.; Afonin, V. I.; Zamuraev, D. O.; Zavolokov, E. V.; Kupyrin, N. V.; Lazarev, Yu. N.; Romanov, Yu. O.; Syrtsova, Yu. G.; Sorokin, I. A.; Tischenko, A. S.; Brukhnevich, G. I.; Voronkova, N. P.; Pekarskaya, L. Z.; Belolipetskiy, V. S.

    The effect of electromagnetic wave generation by the electric current pulse propagating at the superluminal velocity along a conducting surface might be promising to create a high-power wideband microwave generator. The system comprising a plane vacuum photodiode with a transparent anode and using laser radiation to initialize electron emission is a variant to realize this scheme of electromagnetic pulse generation. This chapter presents results of experimental researches in characteristics of such radiating element with the cesium-antimonide cathode of Ø50 mm. The performed researches have shown that the generated wideband pulse (f_0 ≈ 3.3 {{GHz}},Δ f/f_0 ˜ 1) propagates in the direction corresponding to specular reflection of the incident laser radiation. Under the voltage of about 50 kV the electric field strength of 44 kV/m at the distance of 1.3 m has been recorded that corresponds to the generator power ˜10 MW.

  5. Scattering-induced changes in the degree of polarization of a stochastic electromagnetic plane-wave pulse.

    Science.gov (United States)

    Ding, Chaoliang; Cai, Yangjian; Zhang, Yongtao; Pan, Liuzhan

    2012-06-01

    The scattering of a stochastic electromagnetic plane-wave pulse on a deterministic spherical medium is investigated. An analytical formula for the degree of polarization (DOP) of the scattered field in the far zone is derived. Letting pulse duration T(0) → ∞, our formula can be applied to study the scattering of a stationary stochastic electromagnetic light wave. Numerical results show that the DOP of the far zone field is closely determined by the size of the spherical medium when the incident field is a stochastic electromagnetic plane-wave pulse. This is much different from the case when the incident field is a stationary stochastic electromagnetic light wave, where the DOP of the far zone field is independent of the size of the medium. One may obtain the information of the spherical medium by measuring the scattering-induced changes in the DOP of a stochastic electromagnetic plane-wave pulse.

  6. Pulse Structure of Hot Electromagnetic Outflows with Embedded Baryons

    CERN Document Server

    Thompson, Christopher

    2014-01-01

    Gamma-ray bursts (GRBs) show a dramatic pulse structure that requires bulk relativistic motion, but whose physical origin has remained murky. We focus on a hot, magnetized jet that is emitted by a black hole and interacts with a confining medium. Strongly relativistic expansion of the magnetic field, as limited by a corrugation instability, may commence only after it forms a thin shell. Then the observed $T_{90}$ burst duration is dominated by the curvature delay, and null periods arise from angular inhomogeneities, not the duty cycle of the engine. We associate the $O(1)$ s timescale observed in the pulse width distribution of long GRBs with the collapse of the central 2.5-3$M_\\odot$ of a massive stellar core. A fraction of the baryons are shown to be embedded in the magnetized outflow by the hyper-Eddington radiation flux; they strongly disturb the magnetic field after the compactness drops below $\\sim 4\\times 10^3(Y_e/0.5)^{-1}$. The high-energy photons so created have a compressed pulse structure. Delayed...

  7. Special nuclear material detection using pulsed neutron interrogation

    Science.gov (United States)

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

    2007-04-01

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

  8. Dynamical equations and transport coefficients for the metals at high pulse electromagnetic fields

    CERN Document Server

    Volkov, N B; Yalovets, A P

    2016-01-01

    We offer a metal model suitable for the description of fast electrophysical processes in conductors under influence of powerful electronic and laser radiation of femto- and picosecond duration, and also high-voltage electromagnetic pulses with picosecond front and duration less than 1 ns. The obtained dynamic equations for metal in approximation of one quasineutral liquid are in agreement with the equations received by other authors formerly. New wide-range expressions for the electronic conduction in strong electromagnetic fields are obtained and analyzed.

  9. Dynamical equations and transport coefficients for the metals at high pulse electromagnetic fields

    Science.gov (United States)

    Volkov, N. B.; Chingina, E. A.; Yalovets, A. P.

    2016-11-01

    We offer a metal model suitable for the description of fast electrophysical processes in conductors under influence of powerful electronic and laser radiation of femto- and picosecond duration, and also high-voltage electromagnetic pulses with picosecond front and duration less than 1 ns. The obtained dynamic equations for metal in approximation of one quasineutral liquid are in agreement with the equations received by other authors formerly. New wide-range expressions for the electronic conduction in strong electromagnetic fields are obtained and analyzed.

  10. Group delay of electromagnetic pulses through multilayer dielectric mirrors combined with gravitational wave.

    Science.gov (United States)

    Liu, J T; Wu, X; Liu, N H; Li, J; Su, F H

    2013-07-01

    Group delay of electromagnetic pulses through multilayer dielectric mirrors (MDM) combined with gravitational wave (GW) is investigated. Unlike in traditional quantum tunneling, the group delay of a transmitted wave packet irradiated by a GW increases linearly with MDM length. This peculiar tunneling effect can be attributed to electromagnetic wave leakage in a time-dependent photonic bandgap caused by the GW. In particular, we find that the group delay of the tunneling photons is sensitive to GW. Our study provides insight into the nature of the quantum tunnelling as well as a novel process by which to detect the GW.

  11. Electromagnetic activity before initial breakdown pulses of lightning

    Science.gov (United States)

    Marshall, T.; Stolzenburg, M.; Karunarathna, N.; Karunarathne, S.

    2014-11-01

    Lightning flash initiation is studied using electric field change (E-change) measurements made in Florida. An initial E-change (IEC) was found immediately before the first initial breakdown (IB) pulse in both cloud-to-ground (CG) and intracloud (IC) flashes if the E-change sensor was within 80% of the reversal distance of the IEC. For 18 CG flashes, the IECs had an average point dipole moment of 23 C m and an average duration of 0.18 ms; these parameters for 18 IC flashes were -170 C m and 1.53 ms. The IECs of CG flashes began with a change in the slope of the E-change (with respect to time) from zero slope to a positive slope, consistent with downward motion of negative charge and/or upward motion of positive charge. For IECs of IC flashes, the beginning slope change was from zero to negative slope, consistent with upward motion of negative charge and/or downward motion of positive charge. During an IEC, the E-change monotonically increased for CG flashes and monotonically decreased for IC flashes. In 14 of 36 cases, the IEC beginning was coincident with a discrete, impulsive source of VHF radiation; another 13 cases had at least one VHF source during the IEC or the first IB pulse. Before the IECs, there were no preliminary variations detected in the 36 flashes. It is hypothesized that lightning initiation begins with an ionizing event that causes the IEC and that the IEC enhances the ambient electric field to produce the first IB pulse.

  12. Three-dimensional electromagnetic model of the pulsed-power Z-pinch accelerator

    Science.gov (United States)

    Rose, D. V.; Welch, D. R.; Madrid, E. A.; Miller, C. L.; Clark, R. E.; Stygar, W. A.; Savage, M. E.; Rochau, G. A.; Bailey, J. E.; Nash, T. J.; Sceiford, M. E.; Struve, K. W.; Corcoran, P. A.; Whitney, B. A.

    2010-01-01

    A three-dimensional, fully electromagnetic model of the principal pulsed-power components of the 26-MA ZR accelerator [D. H. McDaniel , in Proceedings of the 5th International Conference on Dense Z-Pinches (AIP, New York, 2002), p. 23] has been developed. This large-scale simulation model tracks the evolution of electromagnetic waves through the accelerator’s intermediate-storage capacitors, laser-triggered gas switches, pulse-forming lines, water switches, triplate transmission lines, and water convolute to the vacuum insulator stack. The insulator-stack electrodes are coupled to a transmission-line circuit model of the four-level magnetically insulated vacuum-transmission-line section and double-post-hole convolute. The vacuum-section circuit model is terminated by a one-dimensional self-consistent dynamic model of an imploding z-pinch load. The simulation results are compared with electrical measurements made throughout the ZR accelerator, and are in good agreement with the data, especially for times until peak load power. This modeling effort demonstrates that 3D electromagnetic models of large-scale, multiple-module, pulsed-power accelerators are now computationally tractable. This, in turn, presents new opportunities for simulating the operation of existing pulsed-power systems used in a variety of high-energy-density-physics and radiographic applications, as well as even higher-power next-generation accelerators before they are constructed.

  13. Remote system for counting of nuclear pulses; Sistema remoto de conteo de pulsos nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Nieves V, J.A.; Garcia H, J.M.; Aguilar B, M.A. [Instituto Nacional de Investigaciones Nucleares, Ingenieria Electronica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    In this work, it is describe technically the remote system for counting of nuclear pulses, an integral system of the project radiological monitoring in a petroleum distillation tower. The system acquires the counting of incident nuclear particles in a nuclear detector which process this information and send it in serial form, using the RS-485 toward a remote receiver, which can be a Personal computer or any other device capable to interpret the communication protocol. (Author)

  14. First physics pulses in the Barrel Electromagnetic Calorimeter with cosmics

    CERN Multimedia

    Laurent Serin

    2006-01-01

    The electromagnetic barrel calorimeter has been installed in its final position in October 2005. Since then, the calorimeter is being equipped with front-end electronics. Starting in April 2006, electronics calibration runs are taken a few times per week to debug the electronics and to study the performance in the pit (stability, noise). Today, 10 out of the 32 Front End crates are being read out, amounting to about 35000 channels. cool down, few little typos --> After a 6-week cool down, the barrel cryostat was filled with Liquid Argon in May. The presence of a few shorts (~1MΩ) at the edges of the modules was indicating the possibility of conducting dust having entered into the calorimeter with the flowing liquid. In order to try to improve this situation, the calorimeter was emptied and filled again, but this time by condensating the argon instead of flowing it in liquid phase. The new High Voltage tests are not showing any significant improvement but the situation is statisfactory for ATLAS runn...

  15. The cause of outliers in electromagnetic pulse (EMP) locations

    Energy Technology Data Exchange (ETDEWEB)

    Fenimore, Edward E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-02

    We present methods to calculate the location of EMP pulses when observed by 5 or more satellites. Simulations show that, even with a good initial guess and fitting a location to all of the data, there are sometime outlier results whose locations are much worse than most cases. By comparing simulations using different ionospheric transfer functions (ITFs), it appears that the outliers are caused by not including the additional path length due to refraction rather than being caused by not including higher order terms in the Appleton-Hartree equation. We suggest ways that the outliers can be corrected. These correction methods require one to use an electron density profile along the line of sight from the event to the satellite rather than using the total electron content (TEC) to characterize the ionosphere.

  16. Communication: Neutral atom imaging using a pulsed electromagnetic lens

    Science.gov (United States)

    Gardner, Jamie R.; Anciaux, Erik M.; Raizen, Mark G.

    2017-02-01

    We report on progress towards a neutral atom imaging device that will be used for chemically sensitive surface microscopy and nanofabrication. Our novel technique for improving refractive power and correcting chromatic aberration in atom lenses is based on a fundamental paradigm shift from continuous-beam focusing to a pulsed, three-dimensional approach. Simulations of this system suggest that it will pave the way toward the long-sought goal of true atom imaging on the nanoscale. Using a prototype lens with a supersonic beam of metastable neon, we have imaged complex patterns with lower distortion and higher resolution than has been shown in any previous experiment. Comparison with simulations corroborates the underlying theory and encourages further refinement of the process.

  17. Excitation of plasma waves by nonlinear currents induced by a high-frequency electromagnetic pulse

    Energy Technology Data Exchange (ETDEWEB)

    Grishkov, V. E.; Uryupin, S. A., E-mail: uryupin@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2017-03-15

    Excitation of plasma waves by nonlinear currents induced by a high-frequency electromagnetic pulse is analyzed within the kinetic approach. It is shown that the most efficient source of plasma waves is the nonlinear current arising due to the gradient of the energy density of the high-frequency field. Generation of plasma waves by the drag current is usually less efficient but not negligibly small at relatively high frequencies of electron–ion collisions. The influence of electron collisions on the excitation of plasma waves by pulses of different duration is described quantitatively.

  18. Traversal of electromagnetic pulses through dispersive media with negative refractive index

    Science.gov (United States)

    Nanda, L.; Ramakrishna, S. A.

    2017-05-01

    We investigate the traversal of electromagnetic pulses through dispersive media with negative refractive index in such a way that no resonant effects come into play. It has been verified that for evanescent waves, the definitions of the group delay and the reshaping delay times get interchanged in comparison to the propagating waves. We show that for a negative refractive index medium (NRM) with ɛ(ω)=μ(ω), the reshaping delay time identically vanishes for propagating waves. The total delay time in NRM is otherwise contributed by both the group and the reshaping delay times, whereas for the case of broadband pulses in NRM the total delay time is always subluminal.

  19. America’s Achilles Heel: Defense Against High-altitude Electromagnetic Pulse-policy vs. Practice

    Science.gov (United States)

    2014-12-12

    Energy Regulatory Commission FM Field Manual GRID Act Grid Reliability and Infrastructure Defense Act HEMP High-Altitude Electromagnetic Pulse JP...product to the end user.41 Across the U.S., there are upwards of 40,000 miles of gathering lines from the oil wells, both on and offshore , that feed into...particles are emitted at nearly the speed of light. The emissions can cause disturbances in the solar wind that disrupt satellites and create powerful

  20. Effects of Presowing Pulsed Electromagnetic Treatment of Tomato Seed on Growth, Yield, and Lycopene Content

    OpenAIRE

    Aspasia Efthimiadou; Nikolaos Katsenios; Anestis Karkanis; Panayiota Papastylianou; Vassilios Triantafyllidis; Ilias Travlos; Bilalis, Dimitrios J.

    2014-01-01

    The use of magnetic field as a presowing treatment has been adopted by researchers as a new environmental friendly technique. The aim of this study was to determine the effect of magnetic field exposure on tomato seeds covering a range of parameters such as transplanting percentage, plant height, shoot diameter, number of leaves per plant, fresh weight, dry weight, number of flowers, yield, and lycopene content. Pulsed electromagnetic field was used for 0, 5, 10, and 15 minutes as a presowing...

  1. On the HEMP (high-altitude electromagnetic pulse) environment for protective relays

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, D.E.; Wiggins, C.M.; Salas, T.M. (BDM International, Inc., Albuquerque, NM (USA)); Barnes, P.R. (Oak Ridge National Lab., TN (USA))

    1990-01-01

    An assessment of the transient environment for protective relays produced by high-altitude electromagnetic pulse (HEMP) events is presented in this paper. Several mechanisms for coupling of HEMP to relay terminals are used to develop estimates of possible HEMP threats to relays. These predicted relay responses to HEMP events are compared to measured data on a solid state based relay's impulse strength. 12 refs., 13 figs., 3 tabs.

  2. A Concept for Directly Coupled Pulsed Electromagnetic Acceleration of Plasmas

    Science.gov (United States)

    Thio, Y.C. Francis; Cassibry, Jason T.; Eskridge, Richard; Smith, James; Wu, S. T.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Plasma jets with high momentum flux density are required for a variety of applications in propulsion research. Methods of producing these plasma jets are being investigated at NASA Marshall Space Flight Center. The experimental goal in the immediate future is to develop plasma accelerators which are capable of producing plasma jets with momentum flux density represented by velocities up to 200 km/s and ion density up to 10(exp 24) per cu m, with sufficient precision and reproducibility in their properties, and with sufficiently high efficiency. The jets must be sufficiently focused to allow them to be transported over several meters. A plasma accelerator concept is presented that might be able to meet these requirements. It is a self-switching, shaped coaxial pulsed plasma thruster, with focusing of the plasma flow by shaping muzzle current distribution as in plasma focus devices, and by mechanical tapering of the gun walls. Some 2-D MHD modeling in support of the conceptual design will be presented.

  3. Effects of Pulsed Electromagnetic Field on Differentiation of HUES-17 Human Embryonic Stem Cell Line

    Directory of Open Access Journals (Sweden)

    Yi-Lin Wu

    2014-08-01

    Full Text Available Electromagnetic fields are considered to potentially affect embryonic development, but the mechanism is still unknown. In this study, human embryonic stem cell (hESC line HUES-17 was applied to explore the mechanism of exposure on embryonic development to pulsed electromagnetic field (PEMF for 400 pulses at different electric field intensities and the differentiation of HUES-17 cells was observed after PEMF exposure. The expression of alkaline phosphatase (AP, stage-specific embryonic antigen-3 (SSEA-3, SSEA-4 and the mRNA level and protein level of Oct4, Sox2 and Nanog in HUES-17 cells remained unchanged after PEMF exposure at the electric field intensities of 50, 100, 200 or 400 kV/m. Four hundred pulses PEMF exposure at the electric field intensities of 50, 100, 200 or 400 kV/m did not affect the differentiation of HUES-17 cells. The reason why electromagnetic fields affect embryonic development may be due to other mechanisms rather than affecting the differentiation of embryonic stem cells.

  4. Effects of Multipolar Radiofrequency and Pulsed Electromagnetic Field Treatment for Face and Neck Rejuvenation

    Science.gov (United States)

    de Oliveira, Thais Cristina Ferraz; Rocha, Sheyla de Fatima Soares; Ramos, Daniel Gontijo; Ramos, Camila Gontijo; Carvalho, Michelle Vanessa dos Anjos

    2017-01-01

    Skin aging is a gradual process that leads to wrinkle formation, laxity, and overall changes in skin appearance. In recent years, the demands to noninvasive treatments for facial rejuvenation increased, along with a variety of technologies and devices, such as radiofrequency. The present study aimed to evaluate the clinical effects of a multipolar radiofrequency and pulsed electromagnetic field treatment for face and neck rejuvenation. Eleven patients with mild to moderate grades of photoaging underwent eight radiofrequency and pulsed electromagnetic field treatment sessions, once a week. Clinical photographs were taken before and a week after the end of the treatment, and improvement of facial skin parameters was evaluated by two different investigators. Significant improvement in skin laxity was observed in all eleven patients (100%). Improvement in facial contour was noted in 73% and 100% of patients when analyzed by investigators A and B, respectively. The score for overall improvement in skin condition was 3 ± 0.78 for investigator A and 3.6 ± 0.67 for investigator B. All patients were satisfied with the procedure and noted significant improvement in the skin. The combined multipolar radiofrequency and pulsed electromagnetic field device is effective and safe for treatment of aged skin in Brazilian patients. PMID:28373880

  5. FDTD Computation of Human Eye Exposure to Ultra-wideband Electromagnetic Pulses

    CERN Document Server

    Simicevic, Neven

    2007-01-01

    With an increase in the application of ultra-wideband (UWB) electromagnetic pulses in the communications industry, radar, biotechnology and medicine, comes an interest in UWB exposure safety standards. Despite an increase of the scientific research on bioeffects of exposure to non-ionizing UWB pulses, characterization of those effects is far from complete. A numerical computational approach, such as a finite-difference time domain (FDTD) method, is required to visualize and understand the complexity of broadband electromagnetic interactions. The FDTD method has almost no limits in the description of the geometrical and dispersive properties of the simulated material, it is numerically robust and appropriate for current computer technology. In this paper, a complete calculation of exposure of the human eye to UWB electromagnetic pulses in the frequency range of 3.1-10.6, 22-29, and 57-64 GHz is performed. Computation in this frequency range required a geometrical resolution of the eye of $\\rm 0.1 \\: mm$ and an...

  6. Effects of Multipolar Radiofrequency and Pulsed Electromagnetic Field Treatment for Face and Neck Rejuvenation

    Directory of Open Access Journals (Sweden)

    Thais Cristina Ferraz de Oliveira

    2017-01-01

    Full Text Available Skin aging is a gradual process that leads to wrinkle formation, laxity, and overall changes in skin appearance. In recent years, the demands to noninvasive treatments for facial rejuvenation increased, along with a variety of technologies and devices, such as radiofrequency. The present study aimed to evaluate the clinical effects of a multipolar radiofrequency and pulsed electromagnetic field treatment for face and neck rejuvenation. Eleven patients with mild to moderate grades of photoaging underwent eight radiofrequency and pulsed electromagnetic field treatment sessions, once a week. Clinical photographs were taken before and a week after the end of the treatment, and improvement of facial skin parameters was evaluated by two different investigators. Significant improvement in skin laxity was observed in all eleven patients (100%. Improvement in facial contour was noted in 73% and 100% of patients when analyzed by investigators A and B, respectively. The score for overall improvement in skin condition was 3 ± 0.78 for investigator A and 3.6 ± 0.67 for investigator B. All patients were satisfied with the procedure and noted significant improvement in the skin. The combined multipolar radiofrequency and pulsed electromagnetic field device is effective and safe for treatment of aged skin in Brazilian patients.

  7. Cloaking a metal object from an electromagnetic pulse: A comparison between various cloaking techniques

    CERN Document Server

    Alitalo, Pekka; Tretyakov, Sergei

    2009-01-01

    Electromagnetic cloaks are devices that can be used to reduce the total scattering cross section of various objects. An ideal cloak removes all scattering from an object and thus makes this object "invisible" to the electromagnetic fields that impinge on the object. However, ideal cloaking appears to be possible only at a single frequency. To study cloaking from an electromagnetic pulse we consider propagation of a pulse inside a waveguide with a cloaked metal object inside. There are several ways to achieve cloaking and in this paper we study three such methods, namely, the coordinate-transformation cloak, the transmission-line cloak, and the metal-plate cloak. In the case of the two last cloaks, pulse propagation is studied using experimental data whereas the coordinate-transformation cloak is studied with numerical simulations. The results show that, at least in the studied cases where the cloaked object's diameter is smaller than the wavelength, the cloaks based on transmission-line meshes and metal plate...

  8. The effects of samarium-cobalt magnets and pulsed electromagnetic fields on tooth movement.

    Science.gov (United States)

    Darendeliler, M A; Sinclair, P M; Kusy, R P

    1995-06-01

    The purpose of this study was to determine whether the application of either samarium cobalt magnets or pulsed electromagnetic fields could increase the rate and amount of orthodontic tooth movement observed in guinea pigs. In addition, the objective was to evaluate the effect of a magnetic field on bony physiology and metabolism and to monitor for possible systemic side effects. Fifteen grams of laterally directed orthodontic force were applied to move the maxillary central incisors of a sample of 18 young male Hartley guinea pigs divided into three groups: group 1, an orthodontic coil spring was used to move the incisors; group 2, a pair of samarium-cobalt magnets provided the tooth moving force; and group 3, a coil spring was used in combination with a pulsed electromagnetic field. The results showed that both the static magnetic field produced by the samarium-cobalt magnets and the pulsed electromagnetic field used in combination with the coil spring were successful in increasing the rate of tooth movement over that produced by the coil springs alone. The mechanism producing this effect appears to have involved a reduction in the "lag" phase often seen in orthodontic tooth movement. Both magnetically stimulated groups also showed increases in both the organization and amount of new bone deposited in the area of tension between the orthodontically moved maxillary incisors.

  9. A Search for Meteoroid Lunar Impact Generated Electromagnetic Pulses

    Science.gov (United States)

    Kesaraju, Saiveena; Mathews, John D.; Vierinen, Juha; Perillat, Phil; Meisel, David D.

    2016-11-01

    Lunar white light flashes associated with meteoroid impacts are now regularly observed using modest optical instrumentation. In this paper, we hypothesize that the developing, optically-dense hot ejecta cloud associated with these hypervelocity impacts also produce an associated complex plasma component that rapidly evolves resulting in a highly-transient electro magnetic pulse (EMP) in the VHF/UHF spectral region. Discovery of the characteristics and event frequency of impact EMPs would prove interesting to meteoroid flux and complex plasma physics studies especially if EMPs from the same event are detected from at least two locations on the Earth with relative delays appropriate to the propagation paths. We describe a prototype observational search, conducted in May 2014, for meteoroid lunar-impact EMPs that was conducted using simultaneous, overlapping-band, UHF radio observations at the Arecibo (AO; Puerto Rico) and Haystack (HO, Massachusetts, USA) Observatories. Monostatic/bistatic lunar radar imaging observations were also performed with HO transmitting and HO/AO receiving to confirm tracking, the net delay, and the pointing/timing ephemeris at both observatories. Signal analysis was performed using time-frequency signal processing techniques. Although, we did not conclusively identify EMP returns, this search detected possible EMPs and we have confirmed the search paradigm and established the sensitivity of the AO-HO system in detecting the hypothesized events. We have also characterized the difficult radio-frequency interference environment surrounding these UHF observations. We discuss the wide range of terrestrial-origin, Moon-bounce signals that were observed which additionally validate the observational technique. Further observations are contemplated.

  10. Electromagnetic compatibility (EMC) design guidelines for I and C systems for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, In Koo; Lee, Dong Young; Cha, Kyung Ho; Park, Joo Hyun; Lee, Ki Young [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-02-01

    This report describes the research results on Electromagnetic Compatibility technologies for I and C(Instrumentation and Control) systems for nuclear power plants. As the nuclear industries are adopting the digital equipment rather than the conventional analog type equipment for safety I and C systems as well as non-safety systems of nuclear power plants(NPPs), it is necessary to secure compatibility against EMI(electromagnetic interference) for the digital safety I and C systems. EMI qualification, identified as a regulatory compliance item by US NRC and Korean regulatory body, should be performed in accordance with appropriate standards, because the electromagnetic environment is regarded as one of the environmental factors possible to affect the safety functions. As a technical guide on this EMI issue, this report includes description of code and standards scheme, EMI qualification methods, noise reduction strategies, and survey on noise levels in nuclear power plants. 29 refs., 72 figs., 5 tabs. (Author)

  11. Survey of ambient electromagnetic and radio-frequency interference levels in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kercel, S.W.; Moore, M.R.; Blakeman, E.D.; Ewing, P.D.; Wood, R.T.

    1996-11-01

    This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended observations. The data presented in this report were measured at eight different nuclear units and required 14 months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site location) monitored over extended observation periods (up to 5 weeks) were selected to more completely determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the electromagnetic ambient environment across all measurement conditions at each site provide frequency-dependent profiles for EMI/RFI levels in nuclear power plants.

  12. Measurement of electromagnetic pulses generated during interactions of high power lasers with solid targets

    Science.gov (United States)

    De Marco, M.; Krása, J.; Cikhardt, J.; Pfeifer, M.; Krouský, E.; Margarone, D.; Ahmed, H.; Borghesi, M.; Kar, S.; Giuffrida, L.; Vrana, R.; Velyhan, A.; Limpouch, J.; Korn, G.; Weber, S.; Velardi, L.; Delle Side, D.; Nassisi, V.; Ullschmied, J.

    2016-06-01

    A target irradiated with a high power laser pulse, blows off a large amount of charge and as a consequence the target itself becomes a generator of electromagnetic pulses (EMP) owing to high return current flowing to the ground through the target holder. The first measurement of the magnetic field induced by the neutralizing current reaching a value of a few kA was performed with the use of an inductive target probe at the PALS Laser Facility (Cikhardt et al. Rev. Sci. Instrum. 85 (2014) 103507). A full description of EMP generation should contain information on the spatial distribution and temporal variation of the electromagnetic field inside and outside of the interaction chamber. For this reason, we consider the interaction chamber as a resonant cavity in which different modes of EMP oscillate for hundreds of nanoseconds, until the EMP is transmitted outside through the glass windows and EM waves are attenuated. Since the experimental determination of the electromagnetic field distribution is limited by the number of employed antennas, a mapping of the electromagnetic field has to be integrated with numerical simulations. Thus, this work reports on a detailed numerical mapping of the electromagnetic field inside the interaction chamber at the PALS Laser Facility (covering a frequency spectrum from 100 MHz to 3 GHz) using the commercial code COMSOL Multiphysics 5.2. Moreover we carried out a comparison of the EMP generated in the parallelepiped-like interaction chamber used in the Vulcan Petawatt Laser Facility at the Rutherford Appleton Laboratory, against that produced in the spherical interaction chamber of PALS.

  13. Temporal Skewness of Electromagnetic Pulsed Waves Propagating Through Random Media with Embedded Irregularity Slab

    Institute of Scientific and Technical Information of China (English)

    许正文; 吴健; 霍文平; 吴振森

    2003-01-01

    Electromagnetic pulsed waves can be distorted in the propagation through random media, and their energy dis tributions change along the leading and trailing edge of the waveform, which can be presented by the temporal skewness. The skewness presents asymmetry and is treated by the third-order temporal moment, in which an analytic solution for the two-frequency mutual coherence function is obtained recently. Then, transionospheric pulses are discussed in details. Both theoretical analysis and numerical computation indicate that the contri butions from scattering and dispersion of irregularities dominate over those of background, so the latter can be neglected in most cases. Also, the temporal skewness of a transionospheric pulse is negative and energy is shifted to the leading edge.

  14. Effect of Electromagnetic Pulse Exposure on Brain Micro Vascular Permeability in Rats

    Institute of Scientific and Technical Information of China (English)

    GUI-RONG DING; KANG-CHU LI; XIAO-WU WANG; YONG-CHUN ZHOU; LIAN-BO QIU; JUAN TAN; SHENG-LONG XU; GUO-ZHEN GUO

    2009-01-01

    Objective To observe the effect of electromagnetic pulse (EMP) exposure on cerebral micro vascular permeability in rats.Methods The whole-body of male Sprague-Dawley rats were exposed or sham exposed to 200 pulses or 400 pulses (1 Hz) of EMP at 200 kV/m.At 0.5,1,3,6,and 12 h after EMP exposure,the permeability of cerebral micro vascular was detected by transmission electron microscopy and immunohistochemistry using lanthanum nitrate and endogenous albumin as vascular tracers,respectively. Results The lanthanum nitrate tracer was limited to the micro vascular lumen with no lanthanum nitrate or albumin tracer extravasation in control rat brain.After EMP exposure,the lanthanum nitrate ions reached the tight junction,basal lamina and pericapillary tissue.Similarly,the albumin immunopositive staining was identified in pericapillary tissue.The changes in brain micro vascular permeability were transient,the leakage of micro vascular vessels appeared at 1 h,and reached its peak at 3 h,and nearly recovered at 12 h,after EMP exposure.In addition,the leakage of micro vascular was more obvious after exposure of EMP at 400 pulses than after exposure of EMP at 200 pulses. Conclusion Exposure to 200 and 400 pulses (1 Hz) of EMP at 200 kV/m can increase cerebral micro vascular permeability in rats,which is recoverable.

  15. A versatile computer-controlled pulsed nuclear quadrupole resonance spectrometer

    Science.gov (United States)

    Fisher, Gregory; MacNamara, Ernesto; Santini, Robert E.; Raftery, Daniel

    1999-12-01

    A new, pulsed nuclear quadrupole resonance (NQR) spectrometer capable of performing a variety of pulsed and swept experiments is described. The spectrometer features phase locked, superheterodyne detection using a commercial spectrum analyzer and a fully automatic, computer-controlled tuning and matching network. The tuning and matching network employs stepper motors which turn high power air gap capacitors in a "moving grid" optimization strategy to minimize the reflected power from a directional coupler. In the duplexer circuit, digitally controlled relays are used to switch different lengths of coax cable appropriate for the different radio frequencies. A home-built pulse programmer card controls the timing of radio frequency pulses sent to the probe, while data acquisition and control software is written in Microsoft Quick Basic. Spin-echo acquisition experiments are typically used to acquire the data, although a variety of pulse sequences can be employed. Scan times range from one to several hours depending upon the step resolution and the spectral range required for each experiment. Pure NQR spectra of NaNO2 and 3-aminopyridine are discussed.

  16. A novel digital pulse processing architecture for nuclear instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Moline, Yoann; Thevenin, Mathieu; Corre, Gwenole [CEA, LIST - Laboratoire Capteurs et Architectures electroniques, F-91191 Gif-sur-Yvette, (France); Paindavoine, Michel [CNRS, Universite de Bourgogne - Laboratoire d' Etude de l' Apprentissage et du Developpement, 21000 DIJON, (France)

    2015-07-01

    The field of nuclear instrumentation covers a wide range of applications, including counting, spectrometry, pulse shape discrimination and multi-channel coincidence. These applications are the topic of many researches, new algorithms and implementations are constantly proposed thanks to advances in digital signal processing. However, these improvements are not yet implemented in instrumentation devices. This is especially true for neutron-gamma discrimination applications which traditionally use charge comparison method while literature proposes other algorithms based on frequency domain or wavelet theory which show better performances. Another example is pileups which are generally rejected while pileup correction algorithms also exist. These processes are traditionally performed offline due to two issues. The first is the Poissonian characteristic of the signal, composed of random arrival pulses which requires to current architectures to work in data flow. The second is the real-time requirement, which implies losing pulses when the pulse rate is too high. Despite the possibility of treating the pulses independently from each other, current architectures paralyze the acquisition of the signal during the processing of a pulse. This loss is called dead-time. These two issues have led current architectures to use dedicated solutions based on re-configurable components like Field Programmable Gate Arrays (FPGAs) to overcome the need of performance necessary to deal with dead-time. However, dedicated hardware algorithm implementations on re-configurable technologies are complex and time-consuming. For all these reasons, a programmable Digital pulse Processing (DPP) architecture in a high level language such as Cor C++ which can reduce dead-time would be worthwhile for nuclear instrumentation. This would reduce prototyping and test duration by reducing the level of hardware expertise to implement new algorithms. However, today's programmable solutions do not meet

  17. Software emulator of nuclear pulse generation with different pulse shapes and pile-up

    Science.gov (United States)

    Pechousek, Jiri; Konecny, Daniel; Novak, Petr; Kouril, Lukas; Kohout, Pavel; Celiktas, Cuneyt; Vujtek, Milan

    2016-08-01

    The optimal detection of output signals from nuclear counting devices represents one of the key physical factors that govern accuracy and experimental reproducibility. In this context, the fine calibration of the detector under diverse experimental scenarios, although time costly, is necessary. However this process can be rendered easier with the use of systems that work in lieu of emulators. In this report we describe an innovative programmable pulse generator device capable to emulate the scintillation detector signals, in a way to mimic the detector performances under a variety of experimental conditions. The emulator generates a defined number of pulses, with a given shape and amplitude in the form of a sampled detector signal. The emulator output is then used off-line by a spectrometric system in order to set up its optimal performance. Three types of pulse shapes are produced by our device, with the possibility to add noise and pulse pile-up effects into the signal. The efficiency of the pulse detection, pile-up rejection and/or correction, together with the dead-time of the system, are therein analyzed through the use of some specific algorithms for pulse processing, and the results obtained validate the beneficial use of emulators for the accurate calibration process of spectrometric systems.

  18. Software emulator of nuclear pulse generation with different pulse shapes and pile-up

    Energy Technology Data Exchange (ETDEWEB)

    Pechousek, Jiri, E-mail: jiri.pechousek@upol.cz [Department of Experimental Physics, Faculty of Science, Palacky University, 17. listopadu 1192/12, 771 46 Olomouc (Czech Republic); Konecny, Daniel [Department of Optics, Faculty of Science, Palacky University, 17. listopadu 1192/12, 77 146 Olomouc (Czech Republic); Novak, Petr; Kouril, Lukas; Kohout, Pavel [Department of Experimental Physics, Faculty of Science, Palacky University, 17. listopadu 1192/12, 771 46 Olomouc (Czech Republic); Celiktas, Cuneyt [Department of Physics, Faculty of Science, Ege University, Bornova, Izmir (Turkey); Vujtek, Milan [Department of Experimental Physics, Faculty of Science, Palacky University, 17. listopadu 1192/12, 771 46 Olomouc (Czech Republic)

    2016-08-21

    The optimal detection of output signals from nuclear counting devices represents one of the key physical factors that govern accuracy and experimental reproducibility. In this context, the fine calibration of the detector under diverse experimental scenarios, although time costly, is necessary. However this process can be rendered easier with the use of systems that work in lieu of emulators. In this report we describe an innovative programmable pulse generator device capable to emulate the scintillation detector signals, in a way to mimic the detector performances under a variety of experimental conditions. The emulator generates a defined number of pulses, with a given shape and amplitude in the form of a sampled detector signal. The emulator output is then used off-line by a spectrometric system in order to set up its optimal performance. Three types of pulse shapes are produced by our device, with the possibility to add noise and pulse pile-up effects into the signal. The efficiency of the pulse detection, pile-up rejection and/or correction, together with the dead-time of the system, are therein analyzed through the use of some specific algorithms for pulse processing, and the results obtained validate the beneficial use of emulators for the accurate calibration process of spectrometric systems.

  19. Magneto hydrodynamics simulations of pulsed high density plasmas in electromagnetic guns

    Science.gov (United States)

    Sitaraman, Hariswaran; Raja, Laxminarayan

    2011-10-01

    Electromagnetic guns are a class of devices which uses the Lorentz force to accelerate bulk plasma/conducting solids to velocities ~ km/s. This idea has been widely used in electromagnetic rail guns and in space propulsion systems. The electrically conducting region is typically a pulsed high density thermal plasma which interacts with the bounding solid surface resulting in ablation and materials chemical degradation. We perform a numerical modeling study of the plasma in an electromagnetic gun to understand the discharge physics and in particular study the plasma-surface interactions. The resistive Magneto hydrodynamics (MHD) equations which include the mass, momentum and energy equations for a conducting fluid along with the Maxwell's equations is used for this study. These equations constitute a stiff system with strong coupling between fluid dynamics and electromagnetics. The equations are solved on an unstructured mesh using a cell-centered finite volume formulation. Details of important species in the plasma and the particle and energy flux distribution at the solid boundaries are presented and the consequent plasma-surface interactions under varying operating conditions are discussed.

  20. Stimulation of bone formation and fracture healing with pulsed electromagnetic fields: biologic responses and clinical implications.

    Science.gov (United States)

    Chalidis, B; Sachinis, N; Assiotis, A; Maccauro, G

    2011-01-01

    Pulsed electromagnetic fields (PEMF) have been used for several years to supplement bone healing. However, the mode of action of this non-invasive method is still debated and quantification of its effect on fracture healing is widely varied. At cellular and molecular level, PEMF has been advocated to promote the synthesis of extracellular matrix proteins and exert a direct effect on the production of proteins that regulate gene transcription. Electromagnetic fields may also affect several membrane receptors and stimulate osteoblasts to secrete several growth factors such as bone morphogenic proteins 2 and 4 and TGF-beta. They could also accelerate intramedullary angiogenesis and improve the load to failure and stiffness of the bone. Although healing rates have been reported in up to 87 % of delayed unions and non-unions, the efficacy of the method is significantly varied while patient or fracture related variables could not be clearly associated with a successful outcome.

  1. Remote detection of radioactive material using high-power pulsed electromagnetic radiation.

    Science.gov (United States)

    Kim, Dongsung; Yu, Dongho; Sawant, Ashwini; Choe, Mun Seok; Lee, Ingeun; Kim, Sung Gug; Choi, EunMi

    2017-05-09

    Remote detection of radioactive materials is impossible when the measurement location is far from the radioactive source such that the leakage of high-energy photons or electrons from the source cannot be measured. Current technologies are less effective in this respect because they only allow the detection at distances to which the high-energy photons or electrons can reach the detector. Here we demonstrate an experimental method for remote detection of radioactive materials by inducing plasma breakdown with the high-power pulsed electromagnetic waves. Measurements of the plasma formation time and its dispersion lead to enhanced detection sensitivity compared to the theoretically predicted one based only on the plasma on and off phenomena. We show that lower power of the incident electromagnetic wave is sufficient for plasma breakdown in atmospheric-pressure air and the elimination of the statistical distribution is possible in the presence of radioactive material.

  2. Propagation of an ultimately short electromagnetic pulse in a nonlinear medium described by the fifth-order Duffing model

    Science.gov (United States)

    Maĭmistov, A. I.

    2003-02-01

    We discuss propagation of an ultimately short (single-cycle) pulse of an electromagnetic field in a medium whose dispersion and nonlinear properties can be described by the cubic-quintic Duffing model, i.e., by an oscillator with third-and fifth-order anharmonicity. A system of equations governing the evolution of a unidirectional electromagnetic wave is analyzed without using the approximation of slowly varying envelopes. Three types of solutions of this system describing stationary propagation of a pulse in such a medium are found. When the signs of the anharmonicity constants are different, then the amplitude of a steady-state pulse is limited, but its energy may grow on account of an increase in its duration. The characteristics of such a pulse, referred to as an electromagnetic domain, are discussed.

  3. The Effect of Pulsed Electromagnetic Therapy on Femoral Bone Micro-Structure in Ovariectomized Rats

    Directory of Open Access Journals (Sweden)

    Sarah Hojjati

    2016-05-01

    Full Text Available Background and Aim: Osteoporosis is a metabolic bone disease that can result from cytokines activity such as TNFɑ. The aim of this study was to evaluate the effect of pulsed electromagnet therapy on  femoral strength and bone microstructure in ovariectomized rats. Materials and Methods: In this experimental study, 30 rats were randomly divided into control, experimental1 (ovariectomized and two experimental groups; namely ovariectomized and undergoing pulsed electromagnet groups.  The control and experimental1 groups were kept under controlled conditions, while the two experimental groups were treated with pulsed electromagnet (2.4 mT from 12 postoperative weeks for 30min, 3days a week, for 10 weeks. Then, the subjects were sacrificed and their femoral bones were removed to determine the strength and the bone microstructure  parameters (the trabecular and cortical thicknesses and trabecular distances. In order to determine bone microstructures, the sections were prepared and stained with H&E. Then, Haworth method was used to measure. One-way ANOVA, repeated measurements, and Scheffe post- hoc tests were applied to analyze the obtained data. Statistical analyses were performed using SPSS software (version 16; Chicago,IL. Results: Despite equal initial weight of the subjects (P=0.15, they significantly gained weight after12 and also 22 postoperative weeks (P<,0.001. Cortical and trabecular thicknesses, and femoral strength respectively and significantly decreased in the experimental group 1 .X=220.80±5.90,P<0.001; X=90.34±5.73,P=0.001; X=5.15±1.07,P=0.002. In the experiment. group 2, decrease was .X=255.40±6.02,P<0.001; X=113.50±3.43, P=0.008; X=8.00±1.11,P=0.015; respectively, comparing with the control group (X=232.36±5.13, X=100.50±5.06, X=6.95±1.16. Cortical and trabecular thicknesses, and bone strength significantly increased in the experimental group 2, compared to the experimental  group 1(P<0.001.  There was also a

  4. Electromagnetic plane-wave pulse transmission into a Lorentz half-space.

    Science.gov (United States)

    Cartwright, Natalie A

    2011-12-01

    The propagation of an electromagnetic plane-wave signal obliquely incident upon a Lorentz half-space is studied analytically. Time-domain asymptotic expressions that increase in accuracy with propagation distance are derived by application of uniform saddle point methods on the Fourier-Laplace integral representation of the transmitted field. The results are shown to be continuous in time and comparable with numerical calculations of the field. Arrival times and angles of refraction are given for prominent transient pulse features and the steady-state signal.

  5. Spatial-temporal structure of seismicity of the North Tien Shan and its changeunder effect of high energy electromagnetic pulses

    Directory of Open Access Journals (Sweden)

    N. V. Tarasova

    2004-06-01

    Full Text Available The effect of high-energy electromagnetic pulses emitted by a magnetohydrodynamic generator used as a source for deep electrical sounding of the crust on spatial-temporal structure of seismicity of the North Tien Shan is explored. Five-six years periodicity of changes in spatial distribution of seismicity was revealed. The effect of electromagnetic pulses increases the stability of the spatial distribution of seismicity over time and simultaneously speeds up cycles of its transformations, which develop on stabilization background. Increasing of seismic energy release after electromagnetic impacts is observed basically in most active zones. Periodic variation of efficiency of earthquakes triggering on the distance to the MHD-generator was detected. It was shown that electromagnetic pulses give rise to an appreciable increase in the rate of local earthquakes, occurring around 2-6 days after the pulses. Total earthquakes energy released after start-ups was by 2.03·1015 J greater than the energy released before them. At the same time, the total energy transmitted by the MHD-generator was 1.1·109 J, i.e. six orders of magnitude smaller. Consequently, the electromagnetic pulses initiated the release of the energy that had been stored in the crust due to activity of natural tectonic processes in the form of comparatively small earthquakes, which leads to an additional release of tectonic stresses.

  6. Electromagnetic cascade in high energy electron, positron, and photon interactions with intense laser pulses

    CERN Document Server

    Bulanov, S S; Esarey, E; Leemans, W P

    2013-01-01

    The interaction of high energy electrons, positrons, and photons with intense laser pulses is studied in head-on collision geometry. It is shown that electrons and/or positrons undergo a cascade-type process involving multiple emissions of photons. These photons can consequently convert into electron-positron pairs. As a result charged particles quickly lose their energy developing an exponentially decaying energy distribution, which suppresses the emission of high energy photons, thus reducing the number of electron-positron pairs being generated. Therefore, this type of interaction suppresses the development of the electromagnetic avalanche-type discharge, i.e., the exponential growth of the number of electrons, positrons, and photons does not occur in the course of interaction. The suppression will occur when 3D effects can be neglected in the transverse particle orbits, i.e., for sufficiently broad laser pulses with intensities that are not too extreme. The final distributions of electrons, positrons, and...

  7. Numerical simulation of narrow bipolar electromagnetic pulses generated by thunderstorm discharges

    Science.gov (United States)

    Bochkov, E. I.; Babich, L. P.; Kutsyk, I. M.

    2013-07-01

    Using the concept of avalanche relativistic runaway electrons (REs), we perform numerical simulations of compact intracloud discharge (CID) as a generator of powerful natural electromagnetic pulses (EMPs) in the HF-VHF range, called narrow bipolar pulses (NBPs). For several values of the field overvoltage and altitude at which the discharge develops, the numbers of seed electrons initiating the avalanche are evaluated, with which the calculated EMP characteristics are consistent with the measured NBP parameters. We note shortcomings in the hypothesis assuming participation of cosmic ray air showers in avalanche initiation. The discharge capable of generating NBPs produces REs in numbers close to those in the source of terrestrial γ-ray flashes (TGFs), which can be an argument in favor of a unified NBP and TGF source.

  8. Numerical simulation of narrow bipolar electromagnetic pulses generated by thunderstorm discharges

    Energy Technology Data Exchange (ETDEWEB)

    Bochkov, E. I.; Babich, L. P., E-mail: babich@elph.vniief.ru; Kutsyk, I. M. [All-Russia Research Institute of Experimental Physics, Russian Federal Nuclear Center (Russian Federation)

    2013-07-15

    Using the concept of avalanche relativistic runaway electrons (REs), we perform numerical simulations of compact intracloud discharge (CID) as a generator of powerful natural electromagnetic pulses (EMPs) in the HF-VHF range, called narrow bipolar pulses (NBPs). For several values of the field overvoltage and altitude at which the discharge develops, the numbers of seed electrons initiating the avalanche are evaluated, with which the calculated EMP characteristics are consistent with the measured NBP parameters. We note shortcomings in the hypothesis assuming participation of cosmic ray air showers in avalanche initiation. The discharge capable of generating NBPs produces REs in numbers close to those in the source of terrestrial {gamma}-ray flashes (TGFs), which can be an argument in favor of a unified NBP and TGF source.

  9. NaK flow control by electromagnetic pump of the SNAP-10A space nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Eduardo M.; Braz Filho, Francisco A.; Guimaraes, Lamartine N.F., E-mail: eduardo@ieav.cta.br, E-mail: fbraz@ieav.cta.br, E-mail: guimarae@ieav.cta.br [Instituto de Estudos Avancados (IEAv/DCTA), Sao Jose dos Campos, SP (Brazil)

    2013-07-01

    In the Institute for Advanced Studies (IEAv), were developed, successfully, the first two direct current electromagnetic pumps (DC EM pumps) of Brazil. The first was built with C-type magnet and coils; and the second, with Samarium-Cobalt permanent magnets, for magnetic field generation. Both were tested and performed quite satisfactory. The electromagnetic pump uses the Faraday principle, in which the interaction of the magnetic field and electric current generates the magneto-motive force, which produces the circulation of the fluid. This type of equipment may be used for controlling the liquid metal flow in nuclear space fast reactors. This paper shows the computer programs developed for design and evaluation of DC EM and electromagnetic thermoelectric (EMTE) pumps, the DC EM pump of Samarium-Cobalt magnets data to Mercury loop flow control, the EMTE pump of SNAP space nuclear reactor. It also compares the theoretical results to experimental data of NaK primary loop flow control by electromagnetic thermoelectric pump of the SNAP-10A space nuclear reactor, with satisfactory results, confirming the viability of the electromagnetic pumps evaluation scheme. (author)

  10. Propagation of an electromagnetic pulse through a waveguide with a barrier A time domain solution within classical electrodynamics

    CERN Document Server

    Emig, T

    1996-01-01

    An electromagnetic truncated Gaussian pulse propagates through a waveguide with piecewise different dielectric constants. The waveguide contains a barrier, namely a region of a lower dielectric constant compared to the neighboring regions. This set-up yields a purely imaginary wave vector in the region of the barrier ('electromagnetic tunneling'). We exactly calculate the time-dependent Green's function for a slightly simplified dispersion relation. In order to observe the plain tunneling effect we neglect the distortions caused by the wave guide in obtaining the transmitted pulse. The wave front of the pulse travels with the vacuum speed of light. Nevertheless, behind the barrier, the maximum of the transmitted pulse turns up at an earlier time than in the case without an barrier. This effect will be explained in terms of the energy flow across the barrier. The solutions obtained reproduce the shape of the pulses measured in the tunneling experiments of Enders and Nimtz [J. Phys. (France) I2, 1693 (1992); Ph...

  11. Short-pulse cross-phase modulation in an electromagnetically-induced-transparency medium

    CERN Document Server

    Feizpour, Amir; Steinberg, Aephraim M

    2016-01-01

    Electromagnetically-induced transparency (EIT) has been proposed as a way to greatly enhance cross-phase modulation, with the possibility of leading to few-photon-level optical nonlinearities. This enhancement grows as the transparency window width, \\Delta_EIT, is narrowed. Decreasing \\Delta_EIT, however, increases the response time of the effect, suggesting that for pulses of a given duration, there could be a fundamental limit to the strength of the nonlinearity. We show that in the regimes of most practical interest - narrow EIT windows perturbed by short signal pulses- the enhancement offered by EIT is not only in the magnitude of the nonlinear phase shift but in fact also in its increased duration. That is, for the case of signal pulses much shorter (temporally) than the inverse EIT bandwidth, the narrow window serves to prolong the effect of the passing signal pulse, leading to an integrated phase shift that grows linearly with \\Delta_EIT even though the peak phase shift may saturate; the continued grow...

  12. Detection and Characterization of Flaws in Sprayed on Foam Insulation with Pulsed Terahertz Frequency Electromagnetic Waves

    Science.gov (United States)

    Winfree, William P.; Madaras, Eric I.

    2005-01-01

    The detection and repair of flaws such as voids and delaminations in the sprayed on foam insulation of the external tank reduces the probability of foam debris during shuttle ascent. The low density of sprayed on foam insulation along with it other physical properties makes detection of flaws difficult with conventional techniques. An emerging technology that has application for quantitative evaluation of flaws in the foam is pulsed electromagnetic waves at terahertz frequencies. The short wavelengths of these terahertz pulses make them ideal for imaging flaws in the foam. This paper examines the application of terahertz pulses for flaw detection in foam characteristic of the foam insulation of the external tank. Of particular interest is the detection of voids and delaminations, encapsulated in the foam or at the interface between the foam and a metal backing. The technique is shown to be capable of imaging small voids and delaminations through as much as 20 cm of foam. Methods for reducing the temporal responses of the terahertz pulses to improve flaw detection and yield quantitative characterizations of the size and location of the flaws are discussed.

  13. Mechanisms of amplification of ultrashort electromagnetic pulses in gyrotron traveling wave tube with helically corrugated waveguide

    Science.gov (United States)

    Ginzburg, N. S.; Zotova, I. V.; Sergeev, A. S.; Zaslavsky, V. Yu.; Zheleznov, I. V.; Samsonov, S. V.; Mishakin, S. V.

    2015-11-01

    A time-domain self consistent theory of a gyrotron traveling wave tube with a helically corrugated operating waveguide has been developed. Based on this model, the process of short pulse amplification was studied in regimes of grazing and intersection of the dispersion curves of the electromagnetic wave and the electron beam. In the first case, the possibility of amplification without pulse form distortion was demonstrated for the pulse spectrum width of the order of the gain bandwidth. In the second case, when the electrons' axial velocity was smaller than the wave's group velocity, it was shown that the slippage of the incident signal with respect to the electron beam provides feeding of the signal by "fresh" electrons without initial modulation. As a result, the amplitude of the output pulse can exceed the amplitude of its saturated value for the case of the grazing regime, and, for optimal parameters, the peak output power can be even larger than the kinetic power of the electron beam.

  14. Mechanisms of amplification of ultrashort electromagnetic pulses in gyrotron traveling wave tube with helically corrugated waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, N. S., E-mail: ginzburg@appl.sci-nnov.ru; Zaslavsky, V. Yu. [Institute of Applied Physics of the Russian Academy of Sciences, 46 Ul' yanov Str., 603950 Nizhny Novgorod (Russian Federation); Nizhny Novgorod State University, 23 Gagarin Ave., 603950 Nizhny Novgorod (Russian Federation); Zotova, I. V.; Sergeev, A. S.; Zheleznov, I. V.; Samsonov, S. V.; Mishakin, S. V. [Institute of Applied Physics of the Russian Academy of Sciences, 46 Ul' yanov Str., 603950 Nizhny Novgorod (Russian Federation)

    2015-11-15

    A time-domain self consistent theory of a gyrotron traveling wave tube with a helically corrugated operating waveguide has been developed. Based on this model, the process of short pulse amplification was studied in regimes of grazing and intersection of the dispersion curves of the electromagnetic wave and the electron beam. In the first case, the possibility of amplification without pulse form distortion was demonstrated for the pulse spectrum width of the order of the gain bandwidth. In the second case, when the electrons' axial velocity was smaller than the wave's group velocity, it was shown that the slippage of the incident signal with respect to the electron beam provides feeding of the signal by “fresh” electrons without initial modulation. As a result, the amplitude of the output pulse can exceed the amplitude of its saturated value for the case of the grazing regime, and, for optimal parameters, the peak output power can be even larger than the kinetic power of the electron beam.

  15. Numerical simulation of the coupling of ultra-wide band electromagnetic pulse into landmine by aperture

    Science.gov (United States)

    Gao, Zhen-Ru; Zhao, Hui-Chang; Yang, Li; Wang, Feng-Shan

    2015-09-01

    The modern landmine’s electronic fuse is susceptible to strong interference or can even be damaged by the ultra-wide band electromagnetic pulse (UWB-EMP). The finite-difference time-domain (FDTD) method in lossy media with cylindrical coordinates is used to study the interactions of the UWB-EMP with the landmine. First, the coupling of UWB-EMP into the landmine shielding shell through an aperture is numerically simulated. Second, the coupled electromagnetic field of mine shells made of different shielding materials and with apertures of different sizes is plotted. Third, the aperture coupling laws of UWB-EMP into shells are analyzed and categorized. Such an algorithm is capable of effectively preventing ladder similar errors, and consequently improving the calculation precision, and in addition to adopting the message passing interface (MPI) parallel method to divide the total calculating range into more sub-ranges, the overall calculating efficiency is greatly increased. These calculations are surely a constructive reference for modern landmine design against electromagnetic damage. Project supported by the Postdoctoral Science Foundation of China (Grant No. 2014M552610).

  16. Effects of presowing pulsed electromagnetic treatment of tomato seed on growth, yield, and lycopene content.

    Science.gov (United States)

    Efthimiadou, Aspasia; Katsenios, Nikolaos; Karkanis, Anestis; Papastylianou, Panayiota; Triantafyllidis, Vassilios; Travlos, Ilias; Bilalis, Dimitrios J

    2014-01-01

    The use of magnetic field as a presowing treatment has been adopted by researchers as a new environmental friendly technique. The aim of this study was to determine the effect of magnetic field exposure on tomato seeds covering a range of parameters such as transplanting percentage, plant height, shoot diameter, number of leaves per plant, fresh weight, dry weight, number of flowers, yield, and lycopene content. Pulsed electromagnetic field was used for 0, 5, 10, and 15 minutes as a presowing treatment of tomato seeds in a field experiment for two years. Papimi device (amplitude on the order of 12.5 mT) has been used. The use of pulsed electromagnetic field as a presowing treatment was found to enhance plant growth in tomato plants at certain duration of exposure. Magnetic field treatments and especially the exposure of 10 and 15 minutes gave the best results in all measurements, except plant height and lycopene content. Yield per plant was higher in magnetic field treatments, compared to control. MF-15 treatment yield was 80.93% higher than control treatment. Lycopene content was higher in magnetic field treatments, although values showed no statistically significant differences.

  17. Effects of Presowing Pulsed Electromagnetic Treatment of Tomato Seed on Growth, Yield, and Lycopene Content

    Directory of Open Access Journals (Sweden)

    Aspasia Efthimiadou

    2014-01-01

    Full Text Available The use of magnetic field as a presowing treatment has been adopted by researchers as a new environmental friendly technique. The aim of this study was to determine the effect of magnetic field exposure on tomato seeds covering a range of parameters such as transplanting percentage, plant height, shoot diameter, number of leaves per plant, fresh weight, dry weight, number of flowers, yield, and lycopene content. Pulsed electromagnetic field was used for 0, 5, 10, and 15 minutes as a presowing treatment of tomato seeds in a field experiment for two years. Papimi device (amplitude on the order of 12.5 mT has been used. The use of pulsed electromagnetic field as a presowing treatment was found to enhance plant growth in tomato plants at certain duration of exposure. Magnetic field treatments and especially the exposure of 10 and 15 minutes gave the best results in all measurements, except plant height and lycopene content. Yield per plant was higher in magnetic field treatments, compared to control. MF-15 treatment yield was 80.93% higher than control treatment. Lycopene content was higher in magnetic field treatments, although values showed no statistically significant differences.

  18. EMC Practices focused in the mitigation of Lightning Electromagnetic Pulse (LEMP): Earthing and bonding approach of the IEC 62305

    OpenAIRE

    Malagón-Carvajal, Gabriel; Giraldo-Picón, Wilson; Ordoñez-Plata, Gabriel; Chacón, Julio Cesar

    2013-01-01

    This paper presents the results obtained during the parameter identification of electromagnetic compatibility in lightning protection systems. It sets out a number of good engineering practices, aimed at mitigation of disturbances, transient type, created by an electromagnetic pulse, generated during the grounding of lightning. These disturbances are often reflected as overvoltage and / or overcurrent radiated and conducted or also called surges, the latter a strong impact on the operation of...

  19. Premises Distribution System and Electromagnetic Pulse Protection%综合布线与电磁脉冲防护

    Institute of Scientific and Technical Information of China (English)

    王文锦

    2011-01-01

    阐述了综合布线组成、各个系统布线应注意的问题,以及布线系统的电磁脉冲防护措施,如屏蔽和接地等。电磁脉冲防护的好坏主要取决于综合布线。%The composition of premises distribution system, the distribution problems of each system should be noted and the electromagnetic pulse protection measures, such as shielding and grounding are described. Electromagnetic pulse protection is good or bad depending on premises distribution system.

  20. Treatment of bone marrow edema of the talus with pulsed electromagnetic fields: outcomes in six patients.

    Science.gov (United States)

    Martinelli, Nicolò; Bianchi, Alberto; Sartorelli, Elena; Dondi, Alessandra; Bonifacini, Carlo; Malerba, Francesco

    2015-01-01

    Bone marrow edema (BME) of the talus is a rare, mostly self-limiting cause of foot and ankle pain. We sought to investigate in patients with idiopathic BME of the talus the effectiveness of pulsed electromagnetic fields and to determine the effect of this therapy on magnetic resonance imaging findings. Six patients with BME of the talus confirmed by magnetic resonance imaging were enrolled. Pain was quantified with a visual analog scale from 0 (no pain) to 10 (the worst pain imaginable). The clinical outcome was assessed using the American Orthopaedic Foot and Ankle Society scoring system. Treatment consisted of pulsed electromagnetic field stimulation 8 h/d for 30 days. The device used generated pulses 1.3 milliseconds in duration, with a frequency of 75 Hz and a mean ± SD induced electric field of 3.5 ± 0.5 mV. The mean American Orthopaedic Foot and Ankle Society score improved from 59.4 (range, 40-66) before treatment to 94 (range, 80-100) at the last follow-up. The visual analog scale score decreased significantly from 5.6 (range, 4-7) before treatment to 1 (range, 0-2) at the last follow-up. Magnetic resonance imaging showed that BME improved after 1 month of treatment and resolved completely within 3 months in 5 patients, with normal signal intensity and no signs of progression to avascular necrosis. A significant reduction in BME area was associated with a significant decrease in pain within 3 months of beginning treatment.

  1. Electromagnetism

    CERN Multimedia

    Without the electromagnetic force, you would not be solid. The atoms of your body are held together by electromagnetism: negatively charged electrons are held around the positively charged nucleus. Atoms share electrons to form molecules, so building up the structure of matter. As its name suggests, electromagnetism has a double nature: a moving electric charge creates a magnetic field. This intimate connection between electricity and magnetism was described by James Maxwell in 1864. The electromagnetic force can be both positive and negative : opposite charges attract, whereas like charges repel. Electromagnetic radiation, such as radio, microwaves, light and X-rays, is emitted by charges when they are made to move. For example, an oscillating current in a wire emits radio waves. Text for the interactive: Why do the needles move when you switch on the current ?

  2. Electrochemotherapy by pulsed electromagnetic field treatment (PEMF) in mouse melanoma B16F10 in vivo

    Science.gov (United States)

    Kranjc, Simona; Kranjc, Matej; Scancar, Janez; Jelenc, Jure; Sersa, Gregor

    2016-01-01

    Introduction Pulsed electromagnetic field (PEMF) induces pulsed electric field, which presumably increases membrane permeabilization of the exposed cells, similar to the conventional electroporation. Thus, contactless PEMF could represent a promising approach for drug delivery. Materials and methods Noninvasive electroporation was performed by magnetic field pulse generator connected to an applicator consisting of round coil. Subcutaneous mouse B16F10 melanoma tumors were treated with intravenously injection of cisplatin (CDDP) (4 mg/kg), PEMF (480 bipolar pulses, at frequency of 80 Hz, pulse duration of 340 μs) or with the combination of both therapies (electrochemotherapy − PEMF + CDDP). Antitumor effectiveness of treatments was evaluated by tumor growth delay assay. In addition, the platinum (Pt) uptake in tumors and serum, as well as Pt bound to the DNA in the cells and Pt in the extracellular fraction were measured by inductively coupled plasma mass spectrometry. Results The antitumor effectiveness of electrochemotherapy with CDDP mediated by PEMF was comparable to the conventional electrochemotherapy with CDDP, with the induction of 2.3 days and 3.0 days tumor growth delay, respectively. The exposure of tumors to PEMF only, had no effect on tumor growth, as well as the injection of CDDP only. The antitumor effect in combined treatment was related to increased drug uptake into the electroporated tumor cells, demonstrated by increased amount of Pt bound to the DNA. Approximately 2-fold increase in cellular uptake of Pt was measured. Conclusions The obtained results in mouse melanoma model in vivo demonstrate the possible use of PEMF induced electroporation for biomedical applications, such as electrochemotherapy. The main advantages of electroporation mediated by PEMF are contactless and painless application, as well as effective electroporation compared to conventional electroporation. PMID:27069448

  3. Solidification of Al Alloys Under Electromagnetic Pulses and Characterization of the 3D Microstructures Using Synchrotron X-ray Tomography

    Science.gov (United States)

    Manuwong, Theerapatt; Zhang, Wei; Kazinczi, Peter Lobo; Bodey, Andrew J.; Rau, Christoph; Mi, Jiawei

    2015-07-01

    A novel programmable electromagnetic pulse device was developed and used to study the solidification of Al-15 pct Cu and Al-35 pct Cu alloys. The pulsed magnetic fluxes and Lorentz forces generated inside the solidifying melts were simulated using finite element methods, and their effects on the solidification microstructures were characterized using electron microscopy and synchrotron X-ray tomography. Using a discharging voltage of 120 V, a pulsed magnetic field with the peak Lorentz force of ~1.6 N was generated inside the solidifying Al-Cu melts which were showed sufficiently enough to disrupt the growth of the primary Al dendrites and the Al2Cu intermetallic phases. The microstructures exhibit a strong correlation to the characteristics of the applied pulse, forming a periodical pattern that resonates the frequency of the applied electromagnetic field.

  4. Study on the Disinfection Technology of Electromagnetic Pulse%电磁脉冲灭菌研究

    Institute of Scientific and Technical Information of China (English)

    周蔚红; 张钧

    2000-01-01

    The effects of disinfection technology between transient electromagnetic pulse and continuous microwave were compared. The mechanism of the disinfection was analysed through electronic pulse and magnetic pulse. Based on this study,a new method of disinfection using electromagnetic pulse for keeping food fresh is brought forward.%本文对比了瞬态电磁脉冲与连续波电磁场的消毒灭菌作用,从脉冲电场、脉冲磁场两方面分析了瞬态电磁脉冲的灭菌机理,提出将电磁脉冲的非热生物效应应用于食品的消毒杀菌,为食品保鲜业的发展开拓一种新方法。

  5. Electromagnetic Signature Technique as a Promising Tool to Verify Nuclear Weapons Storage and Dismantlement under a Nuclear Arms Control Regime

    Energy Technology Data Exchange (ETDEWEB)

    Bunch, Kyle J.; Williams, Laura S.; Jones, Anthony M.; Ramuhalli, Pradeep

    2012-08-01

    The 2010 ratification of the New START Treaty has been widely regarded as a noteworthy national security achievement for both the Obama administration and the Medvedev-Putin regime, but deeper cuts are envisioned under future arms control regimes. Future verification needs will include monitoring the storage of warhead components and fissile materials and verifying dismantlement of warheads, pits, secondaries, and other materials. From both the diplomatic and technical perspectives, verification under future arms control regimes will pose new challenges. Since acceptable verification technology must protect sensitive design information and attributes, non-nuclear non-sensitive signatures may provide a significant verification tool without the use of additional information barriers. The use of electromagnetic signatures to monitor nuclear material storage containers is a promising technology with the potential to fulfill these challenging requirements. Research performed at Pacific Northwest National Laboratory (PNNL) has demonstrated that low frequency electromagnetic signatures of sealed metallic containers can be used to confirm the presence of specific components on a “yes/no” basis without revealing classified information. Arms control inspectors might use this technique to verify the presence or absence of monitored items, including both nuclear and non-nuclear materials. Although additional research is needed to study signature aspects such as uniqueness and investigate container-specific scenarios, the technique potentially offers a rapid and cost-effective tool to verify reduction and dismantlement of U.S. and Russian nuclear weapons.

  6. Pulsed-induced electromagnetically induced transparency in the acetylene-filled hollow-core fibers

    Science.gov (United States)

    Rodríguez, Nayeli Casillas; Stepanov, Serguei; Miramontes, Manuel Ocegueda; Hernández, Eliseo Hernández

    2017-06-01

    Experimental results on pulsed excitation of electromagnetically induced transparency (EIT) in the acetylene-filled hollow-core photonic crystal fiber (HC-PCF) at pressures 0.1-0.4 Torr are reported. The EIT was observed both in Λ and V interaction configurations with the continuous probe wave tuned to R9 (1520.08 nm) acetylene absorption line and with the control pulses tuned to P11 (1531.58 nm) and P9 (1530.37 nm) lines, respectively. The utilized control pulses were of up to 40 ns duration with qualitative explanation of reduction in the counter-propagation EIT efficiency a simple model of the accelerated mismatch of the two-frequency EIT resonance with deviation of the molecule thermal velocity from the resonance value was utilized. It was shown experimentally that the EIT efficiencies in both configurations do not depend on the longitudinal velocity of the molecules. The characteristic relaxation time of the of the EIT response was found to be about 9 ns, i.e., is close to the relaxation times T 1,2 of the acetylene molecules under the utilized experimental conditions.

  7. Electromagnetic cascade in high-energy electron, positron, and photon interactions with intense laser pulses

    Science.gov (United States)

    Bulanov, S. S.; Schroeder, C. B.; Esarey, E.; Leemans, W. P.

    2013-06-01

    The interaction of high-energy electrons, positrons, and photons with intense laser pulses is studied in head-on collision geometry. It is shown that electrons and/or positrons undergo a cascade-type process involving multiple emissions of photons. These photons can consequently convert into electron-positron pairs. As a result charged particles quickly lose their energy developing an exponentially decaying energy distribution, which suppresses the emission of high-energy photons, thus reducing the number of electron-positron pairs being generated. Therefore, this type of interaction suppresses the development of the electromagnetic avalanche-type discharge, i.e., the exponential growth of the number of electrons, positrons, and photons does not occur in the course of interaction. The suppression will occur when three-dimensional effects can be neglected in the transverse particle orbits, i.e., for sufficiently broad laser pulses with intensities that are not too extreme. The final distributions of electrons, positrons, and photons are calculated for the case of a high-energy e-beam interacting with a counterstreaming, short intense laser pulse. The energy loss of the e-beam, which requires a self-consistent quantum description, plays an important role in this process, as well as provides a clear experimental observable for the transition from the classical to quantum regime of interaction.

  8. The effect of long-term pulsing electromagnetic field stimulation on experimental osteoporosis of rats.

    Science.gov (United States)

    Mishima, S

    1988-03-01

    The author performed experiments in order to investigate what biological effect on the bone would be produced by long-term pulsing electromagnetic field (PEMF) systemic stimulation. In some of the mature female rats used as experimental animals, bilateral ovariectomy and right sciatic neurectomy were performed in order to make a model osteoporosis. PEMF stimulation was produced by repetitive pulse burst (RPB) waves at a positive amplitude of 25 mV, negative amplitude of 62.5 mV, burst width of 4.2 ms, pulse width of 230 microseconds and 12 Hz, with the magnetic field strength within a cage being set at 3-10 Gauss. PEMF stimulation over 6 months did not produce any effects on the physiologically aged bones. PEMF stimulation also did not produce any effects on losed cortical bone in osteoporotic hindlegs. On the other hand, an increase of bone volume and bone formation activity was observed in the cancellous bone of osteoporotic hindlegs. These findings suggested that PEMF stimulation exerted a preventive effect against bone loss of osteoporotic hindlegs. Furthermore, an observed increase in bone marrow blood flow seemed to be related with this increase of bone volume and bone formation activity.

  9. In vitro stimulation with a strongly pulsed electromagnetic field on rat basophilic leukemia cells

    Science.gov (United States)

    Choi, J. W.; Shin, S. C.; Kim, S.; Chung, E. R.; Bang, J. H.; Cho, G. I.; Choi, S. D.; Park, Y. S.; Jang, T. S.; Yoo, Y. M.; Lee, S. S.; Hwang, D. G.

    2010-05-01

    In this study, the effects of pulsed electromagnetic field stimulation with a strong magnetic field on rat basophilic leukemia (RBL-2H3) cells were investigated to confirm the efficacy of the magnetic stimulator for biomedical applications. The maximum intensity of the magnetic field generated from the stimulation coil was 0.203 T, and the transition time was 126 μs. The oscillation time and frequency of the pulsed field were almost 0.1 ms and 8 kHz, respectively. The cell count as well as the mRNA expression and DNA sequence of the cytokine genes, such as the tumor necrosis factor-α (TNF-α) and interleukin-4 (IL-4), of the stimulated RBL-2H3 cells were analyzed with a hemocytometer and via reverse transcriptase polymerase chain reaction to determine the physiological response under a strong pulse field. After 12 h stimulation, cell death was observed at an increasing scale with the increase in the stimulation time. On the other hand, the cells that were stimulated for 10 min almost doubled as the interval time between the stimulations was extended.

  10. Applications of digital pulse processing in nuclear spectroscopy

    CERN Document Server

    Grzywacz, R

    2003-01-01

    Data acquisition systems for nuclear spectroscopy have traditionally been based on hybrid systems with analog shaping amplifiers followed by analog-to-digital converters. Recently, however, new systems based on digital signal processing concepts have been developed. For example, one specific design, the Digital Gamma Finder (DGF-4C), has been used extensively for particle- and gamma-spectroscopy of nuclei far from stability. Using the DGF-4C, a variety of data acquisition systems have been implemented and used for measurements with semiconductor and scintillator detectors at recoil separators like the RMS at ORNL, the FRS at GSI and LISE at GANIL. Some novel features and unique advantages, such as trigger-less operation and pulse shape recording, are discussed in the context of selected studies.

  11. Resonant two-photon annihilation of an electron-positron pair in a pulsed electromagnetic wave

    Science.gov (United States)

    Voroshilo, A. I.; Roshchupkin, S. P.; Nedoreshta, V. N.

    2016-09-01

    Two-photon annihilation of an electron-positron pair in the field of a plane low-intensity circularly polarized pulsed electromagnetic wave was studied. The conditions for resonance of the process which are related to an intermediate particle that falls within the mass shell are studied. In the resonant approximation the probability of the process was obtained. It is demonstrated that the resonant probability of two-photon annihilation of an electron-positron pair may be several orders of magnitude higher than the probability of this process in the absence of the external field. The obtained results may be experimentally verified by the laser facilities of the international megaprojects, for example, SLAC (National Accelerator Laboratory), FAIR (Facility for Antiproton and Ion Research), and XFEL (European X-Ray Free-Electron Laser).

  12. Study on the Sensitivity of Landmine Electrical Fuse Circuit Under the Interference of Natural Electromagnetic Pulse

    Science.gov (United States)

    Qin, Dechun

    Landmine electrical fuse circuits on the battlefield will be interfered by natural electromagnetic pulse such as electrostatic discharge and lightning, which will undermine the circuit performance and trigger the early burst or mistaken burst of the landmines. In this paper, numerically simulation analysis is conducted on the electrostatic and lightning effects received by the landmine fuse circuit by means of building simulation model of the fuse circuit and analyzing the electric and magnetic field changes of the observation The mechanism of the influence of electrostatic discharge and lightning on the sensitivity of the fuse circuit is explored. The conclusion is that electrostatic effect cause the mistaken burst of the landmines by enabling the interference voltage to reach the components turn-on threshold and cause the circuit malfunction, and lighting effect by long period accumulation of energy.

  13. Time-Frequency Analysis of Electromagnetic Pulse Response from a Spherical Target

    Institute of Scientific and Technical Information of China (English)

    陈东; 金亚秋

    2003-01-01

    Transient backscattering from a spherical target under incidence of an electromagnetic short pulse is studied. The target can be a perfectly conducting sphere, a dielectric sphere or a dielectric spherical shell. To understand the scattering mechanism from transient impulse echoes for target detection, both the short-time Fourier transform(STFT) and the wavelet transform (WT) are applied to retrieval of scattering information from the backscattering data. Analysis in both the time and frequency domains demonstrates that the WT is more feasible than the STFT to clarifying scattering process of the scatterer because of its excellent multi-resolution characteristic. This technique shall be helpful for scattering analysis and detection of more complex single or multi-targets.

  14. Detection of electromagnetic pulses produced by hypervelocity micro particle impact plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Close, Sigrid; Lee, Nicolas; Johnson, Theresa; Goel, Ashish; Fletcher, Alexander [Department of Aeronautics and Astronautics, Stanford University, Stanford, California 94305 (United States); Linscott, Ivan; Strauss, David; Lauben, David [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Srama, Ralf; Mocker, Anna; Bugiel, Sebastian [Institut für Raumfahrtsysteme, Universität Stuttgart, Pfaffenwaldring 29, 70569 Stuttgart (Germany)

    2013-09-15

    Hypervelocity micro particles (mass < 1 ng), including meteoroids and space debris, routinely impact spacecraft and produce plasmas that are initially dense (∼10{sup 28} m{sup −3}), but rapidly expand into the surrounding vacuum. We report the detection of radio frequency (RF) emission associated with electromagnetic pulses (EMPs) from hypervelocity impacts of micro particles in ground-based experiments using micro particles that are 15 orders of magnitude less massive than previously observed. The EMP production is a stochastic process that is influenced by plasma turbulence such that the EMP detection rate that is strongly dependent on impact speed and on the electrical charge conditions at the impact surface. In particular, impacts of the fastest micro particles occurring under spacecraft charging conditions representative of high geomagnetic activity are the most likely to produce RF emission. This new phenomenon may provide a source for unexplained RF measurements on spacecraft charged to high potentials.

  15. Studies on antioxidant enzymes in mice exposed to pulsed electromagnetic fields.

    Science.gov (United States)

    Eraslan, Gokhan; Bilgili, Ali; Akdogan, Mehmet; Yarsan, Ender; Essiz, Dinc; Altintas, Levent

    2007-02-01

    In this study, 56 female albino mice weighing 30-35 g were used. The animals were divided into a control and an experimental group. The animals in the experimental group were subjected to a pulsed electromagnetic field (PEMF) with a field magnitude of 50 Hz and 2 mT for 8h each day between 0900 and 1700 for 90 days. In both control and experimental groups, blood was sampled at 45, 60, and 90 days in heparinized tubes and erythrocyte malondialdehyde levels, and superoxide dismutase, glutathione peroxidase, catalase, and glucose-6-phosphate dehydrogenase activities were determined. The results revealed that the PEMF applied chronically within the given period and field magnitude does not cause oxidative damage.

  16. Transcranial low voltage pulsed electromagnetic fields in patients with treatment-resistant depression

    DEFF Research Database (Denmark)

    Martiny, Klaus Per Juul; Lunde, Marianne; Bech, Per

    2010-01-01

    BACKGROUND: Approximately 30% of patients with depression are resistant to antidepressant drugs. Repetitive transcranial magnetic stimulation (rTMS) has been found effective in combination with antidepressants in this patient group. The aim of this study was to evaluate the antidepressant effect...... of a new principle using low-intensity transcranially applied pulsed electromagnetic fields (T-PEMF) in combination with antidepressants in patients with treatment-resistant depression. METHODS: This was a sham-controlled double-blind study comparing 5 weeks of active or sham T-PEMF in patients......-resistant depression. Few side effects were observed. Mechanism of the antidepressant action, in light of the known effects of PEMF stimulation to the brain, is discussed....

  17. Radio pulses from electromagnetic, hadronic and neutrino-induced showers up to EeV energies

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Muniz, Jaime, E-mail: jaime.alvarezmuniz@gmail.com [Depto. de Fisica de Particulas and Inst. Galego de Fisica de Altas Enerxias, Univ. de Santiago de Compostela, 15782 Santiago (Spain); Carvalho, Washington R.; Zas, Enrique [Depto. de Fisica de Particulas and Inst. Galego de Fisica de Altas Enerxias, Univ. de Santiago de Compostela, 15782 Santiago (Spain); Romero-Wolf, Andres [Department of Physics and Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Tueros, Matias [Depto. de Fisica, Facultad de Ciencias Exactas, Univ. Nacional de La Plata (Argentina)

    2012-01-11

    The radio pulses emitted by electromagnetic, hadronic, and neutrino-induced showers are calculated for showers of energies in the EeV range and above in ice and in air. These are obtained in three-dimensional simulations of both the shower and the radio emission. An AIRES-based Monte Carlo code, ZHAIRES, has been developed for this purpose that allows us to predict the radio emission in both the time and frequency domains. The algorithms used, obtained from first principles, predict the radio emission due to all emission mechanisms, including the deflection of charged particles in the Earth's magnetic field. The code which has been extended to calculate in the Fresnel regime can reproduce the full complexity of the relevant shower phenomena.

  18. The therapeutic effect of a pulsed electromagnetic field on the reproductive patterns of male Wistar rats exposed to a 2.45-GHz microwave field

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar

    2011-01-01

    Full Text Available INTRODUCTION: Environmental exposure to man-made electromagnetic fields has been steadily increasing with the growing demand for electronic items that are operational at various frequencies. Testicular function is particularly susceptible to radiation emitted by electromagnetic fields. OBJECTIVES: This study aimed to examine the therapeutic effects of a pulsed electromagnetic field (100 Hz on the reproductive systems of male Wistar rats (70 days old. METHODS: The experiments were divided into five groups: microwave sham, microwave exposure (2.45 GHz, pulsed electromagnetic field sham, pulsed electromagnetic field (100 Hz exposure, and microwave/pulsed electromagnetic field exposure. The animals were exposed for 2 hours/day for 60 days. After exposure, the animals were sacrificed, their sperm was used for creatine and caspase assays, and their serum was used for melatonin and testosterone assays. RESULTS: The results showed significant increases in caspase and creatine kinase and significant decreases in testosterone and melatonin in the exposed groups. This finding emphasizes that reactive oxygen species (a potential inducer of cancer are the primary cause of DNA damage. However, pulsed electromagnetic field exposure relieves the effect of microwave exposure by inducing Faraday currents. CONCLUSIONS: Electromagnetic fields are recognized as hazards that affect testicular function by generating reactive oxygen species and reduce the bioavailability of androgen to maturing spermatozoa. Thus, microwave exposure adversely affects male fertility, whereas pulsed electromagnetic field therapy is a non-invasive, simple technique that can be used as a scavenger agent to combat oxidative stress.

  19. Clinical Assessment of the RHUMART System Based on the Use of Pulsed Electromagnetic Fields with Low Frequency.

    Science.gov (United States)

    Begue-Simon, A-M.; Drolet, R. A.

    1993-01-01

    Difficulties in using the double-blind method of evaluation with use of Pulsed Electromagnetic Fields led to an open evaluation with 96 patients with musculoskeletal diseases, neurological disorders, circulatory diseases, or gastroenterological diseases. This paper reports the impact of use on dependency, pain, and patient satisfaction. (DB)

  20. Treatment of knee osteoarthritis with pulsed electromagnetic fields: a randomized, double-blind, placebo-controlled study

    DEFF Research Database (Denmark)

    Thamsborg, G; Florescu, A; Oturai, P

    2005-01-01

    OBJECTIVE: The investigation aimed at determining the effectiveness of pulsed electromagnetic fields (PEMF) in the treatment of osteoarthritis (OA) of the knee by conducting a randomized, double-blind, placebo-controlled clinical trial. DESIGN: The trial consisted of 2h daily treatment 5 days per...

  1. Pulsed electromagnetic field at 9.71 GHz increase free radical production in yeast (Saccharomyces cerevisiae).

    Science.gov (United States)

    Crouzier, D; Perrin, A; Torres, G; Dabouis, V; Debouzy, J-C

    2009-05-01

    Potential human health hazards have been reported after exposure to electromagnetic fields at low power density. Increased oxidative stress has been suggested as a potential mechanism involved in long-term effect of such exposure. In the present work, yeast cultures were exposed for 20 min to a 9.71 GHz pulsed electromagnetic field at specific absorption rates (SAR) from 0.5 W/kg to 16 W/kg. Oxidative perturbations were investigated using ESR spin trapping experiments and their impacts on membrane fluidity were assessed using spin label five nitroxide stearate. The experiments using the water-soluble spin trap alpha-(4-pyridyl-1-oxide)-N-t-butylnitrone and the lipid-soluble N-tert-butyl-alpha-phenylnitrone showed an increase of spin adduct production both in low power density exposure (SAR4 W/kg). The membrane fluidity diminutions after exposure in all the conditions were consistent with lipid peroxidation. The overall results suggest an increase of the free radical production in the intra cellular compartment; however no effect on the yeast vitality was found.

  2. 2nd International Conference on Ultra-Wideband, Short-Pulse Electromagnetics

    CERN Document Server

    Felsen, Leopold

    1995-01-01

    The papers published in this volume were presented at the Second International Conference on Ultra-WidebandiShort-Pulse (UWB/SP) Electromagnetics, ApriIS-7, 1994. To place this second international conference in proper perspective with respect to the first conference held during October 8-10, 1992, at Polytechnic University, some background information is necessary. As we had hoped, the first conference struck a responsive cord, both in timeliness and relevance, among the electromagnetic community 1. Participants at the first conference already inquired whether and when a follow-up meeting was under consideration. The first concrete proposal in this direction was made a few months after the first conference by Prof. A. Terzuoli of the Air Force Institute of Technology (AFIT), Dayton, Ohio, who has been a strong advocate of time-domain methods and technologies. He initially proposed a follow-up time-domain workshop under AFIT auspices. Realizing that interest in this subject is lodged also at other Air Force i...

  3. Influence of Pulsed Electromagnetic Field on Plant Growth, Nutrient Absorption and Yield of Durum Wheat

    Directory of Open Access Journals (Sweden)

    Nikolaos KATSENIOS

    2015-12-01

    Full Text Available Researchers have adopted the use of magnetic field as a new pre-sowing, environmental friendly technique. Enhancements on plant characteristics with economic impact on producer’s income could be the future of a modern, organic and sustainable agriculture. A field experiment was established at Soil Science Institute of Athens, Lycovrissi, Greece, in the winter of 2014. Two durum wheat cultivars were used. It was a pot experiment with 6 treatments (2 cultivars with 3 magnetic field time exposure. The seeds were treated using a PAPIMI electromagnetic field generator for 0, 30 and 45 minutes one day before planting. The experiment followed a completely randomized design with six treatments and 30 replications. The aim of this study was to evaluate the positive effect of magnetic field pre-sowing treatment in a wide range of plant measurements, including yield. The influence of pulsed electromagnetic field on two varieties of durum wheat seeds showed some statistically significant differences at the 0.05 level in growth measurements, physiological measurements and root growth measurements. Plant tissue analysis showed that magnetic field treatments had higher values than control in total nitrogen, phosphorus, potassium, magnesium, copper (only MF-45, zinc (only MF-30 and boron content, although values showed statistically significant differences only in total nitrogen. The results indicate that this innovative technique can increase the yield of durum wheat, through enhanced absorption of nutrients. Pre-sowing treatment of the seeds leads to vigorous plant growth that are more productive.

  4. Electromagnetic radiation from nuclear collisions at RHIC energies

    CERN Document Server

    Turbide, Simon; Frodermann, Evan; Heinz, Ulrich

    2008-01-01

    The hot and dense strongly interacting matter created in collisions of heavy nuclei at RHIC energies is modeled with relativistic hydrodynamics, and the spectra of real and virtual photons produced at mid-rapidity in these events are calculated. Several different sources are considered, and their relative importance is compared. Specifically, we include jet fragmentation, jet-plasma interactions, the emission of radiation from the thermal medium and from primordial hard collisions. Our calculations consistently take into account jet energy loss, as evaluated in the AMY formalism. We obtain results for the spectra, the nuclear modification factor (R_AA), and the azimuthal anisotropy (v_2) that agree with the photon measurements performed by the PHENIX collaboration at RHIC.

  5. Electromagnetic radiation as a probe of the initial state and of viscous dynamics in relativistic nuclear collisions

    CERN Document Server

    Vujanovic, Gojko; Denicol, Gabriel S; Luzum, Matthew; Jeon, Sangyong; Gale, Charles

    2016-01-01

    The penetrating nature of electromagnetic signals makes them suitable probes to explore the properties of the strongly-interacting medium created in relativistic nuclear collisions. We examine the effects of the initial conditions and shear relaxation time on the spectra and flow coefficients of electromagnetic probes, using an event-by-event 3+1D viscous hydrodynamic simulation (MUSIC).

  6. 3D modeling of lightning-induced electromagnetic pulses on Venus, Jupiter and Saturn

    Science.gov (United States)

    Pérez-Invernón, Francisco J.; Luque, Alejandro; Gordillo-Vázquez, Francisco J.

    2017-04-01

    Atmospheric electricity is a common phenomenon in some planets of The Solar System. We know that atmospheric discharges exist on Earth and gaseous planets; however, some characteristics of lightning on Saturn and Jupiter as well as their relevance on the effects of lightning in the atmospheres of these planets are still unknown. In the case of Venus, there exist some radio evidences of lightning, but the lack of optical observations suggests exploring indirect methods of detection, such as searching for lightning-induced transient optical emissions from the upper atmosphere. The Akatsuki probe, currently orbiting Venus, is equipped with a camera whose temporal resolution is high enough to detect optical emissions from lightning discharges and to measure nightglow enhancements. In this work, we extend previous models [1,2] to investigate the chemical impact and transient optical emissions produced by possible lightning-emitted electromagnetic pulses (EMP) in Venus, Saturn and Jupiter. Using a 3D FDTD ("Finite Differences Time Domain") model we solve the Maxwell equations coupled with the Langevin equation for electrons [3] and with a kinetic scheme, different for each planetary atmosphere. This method is useful to investigate the temporal and spatial impact of lightning-induced electromagnetic fields in the atmosphere of each planet for different lightning characteristics (e.g. energy released, orientation). This 3D FDTD model allows us to include the saturnian and jovian background magnetic field inclination and magnitude at different latitudes, and to determine the effects of different lightning channel inclinations. Results provide useful information to interpret lightning observations on giant gaseous planets and in the search for indirect optical signals from atmospheric discharge on Venus such as fast nightglow transient enhancements related to lightning as seen on Earth. Furthermore, we underline the observation of electrical discharges characteristics as a

  7. Self-consistent evolution of plasma discharge and electromagnetic fields in a microwave pulse compressor

    Energy Technology Data Exchange (ETDEWEB)

    Shlapakovski, A. S.; Beilin, L.; Krasik, Ya. E. [Physics Department, Technion 32000 Haifa (Israel); Hadas, Y. [Department of Applied Physics, Rafael, POBox 2250, Haifa 31021 (Israel); Schamiloglu, E. [Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    2015-07-15

    Nanosecond-scale evolution of plasma and RF electromagnetic fields during the release of energy from a microwave pulse compressor with a plasma interference switch was investigated numerically using the code MAGIC. The plasma was simulated in the scope of the gas conductivity model in MAGIC. The compressor embodied an S-band cavity and H-plane waveguide tee with a shorted side arm filled with pressurized gas. In a simplified approach, the gas discharge was initiated by setting an external ionization rate in a layer crossing the side arm waveguide in the location of the electric field antinode. It was found that with increasing ionization rate, the microwave energy absorbed by the plasma in the first few nanoseconds increases, but the absorption for the whole duration of energy release, on the contrary, decreases. In a hybrid approach modeling laser ignition of the discharge, seed electrons were set around the electric field antinode. In this case, the plasma extends along the field forming a filament and the plasma density increases up to the level at which the electric field within the plasma decreases due to the skin effect. Then, the avalanche rate decreases but the density still rises until the microwave energy release begins and the electric field becomes insufficient to support the avalanche process. The extraction of the microwave pulse limits its own power by terminating the rise of the plasma density and filament length. For efficient extraction, a sufficiently long filament of dense plasma must have sufficient time to be formed.

  8. Self-consistent evolution of plasma discharge and electromagnetic fields in a microwave pulse compressor

    Science.gov (United States)

    Shlapakovski, A. S.; Beilin, L.; Hadas, Y.; Schamiloglu, E.; Krasik, Ya. E.

    2015-07-01

    Nanosecond-scale evolution of plasma and RF electromagnetic fields during the release of energy from a microwave pulse compressor with a plasma interference switch was investigated numerically using the code MAGIC. The plasma was simulated in the scope of the gas conductivity model in MAGIC. The compressor embodied an S-band cavity and H-plane waveguide tee with a shorted side arm filled with pressurized gas. In a simplified approach, the gas discharge was initiated by setting an external ionization rate in a layer crossing the side arm waveguide in the location of the electric field antinode. It was found that with increasing ionization rate, the microwave energy absorbed by the plasma in the first few nanoseconds increases, but the absorption for the whole duration of energy release, on the contrary, decreases. In a hybrid approach modeling laser ignition of the discharge, seed electrons were set around the electric field antinode. In this case, the plasma extends along the field forming a filament and the plasma density increases up to the level at which the electric field within the plasma decreases due to the skin effect. Then, the avalanche rate decreases but the density still rises until the microwave energy release begins and the electric field becomes insufficient to support the avalanche process. The extraction of the microwave pulse limits its own power by terminating the rise of the plasma density and filament length. For efficient extraction, a sufficiently long filament of dense plasma must have sufficient time to be formed.

  9. Effect of Electromagnetic Pulse Exposure on Permeability of Blood-testicle Barrier in Mice

    Institute of Scientific and Technical Information of China (English)

    XIAO-WU WANG; GUI-RONG DING; CHANG-HONG SHI; TAO ZHAO; JIE ZHANG; LI-HUA ZENG; GUO-ZHEN GUO

    2008-01-01

    Objective To study the effect of electromagnetic pulse (EMP) exposure on the permeability of blood-testicle barrier (BTB) in mice. Methods Adult male BALB/c mice were exposed to EMP at 200 kV/m for 200 pulses with 2 seconds interval. The mice were injected with 2% Evans Blue solution through caudal vein at different time points after exposure, and the permeability of BTB was monitored using a fluorescence microscope. The testis sample for the transmission electron microscopy was prepared at 2 h after EMP exposure. The permeability of BTB in mice was observed by using Evans Blue tracer and lanthanum nitrate tracer. Results After exposure, cloudy Evans Blue was found in the testicle convoluted seminiferous tubule of mice. Lanthanum nitrate was observed not only between testicle spermatogonia near seminiferous tubule wall and sertoli cells, but also between sertofi cells and primary spermatocyte or secondary spermatocyte. In contrast,lanthanum nitrate in control group was only found in the testicle sertoli cells between seminiferous tubule and near seminiferous tubule wall. Conclusion EMP exposure could increase the permeability of BTB in the mice.

  10. Analysis of the damage threshold of the GaAs pseudomorphic high electron mobility transistor induced by the electromagnetic pulse

    Science.gov (United States)

    Xi, Xiao-Wen; Chai, Chang-Chun; Liu, Yang; Yang, Yin-Tang; Fan, Qing-Yang; Shi, Chun-Lei

    2016-08-01

    An electromagnetic pulse (EMP)-induced damage model based on the internal damage mechanism of the GaAs pseudomorphic high electron mobility transistor (PHEMT) is established in this paper. With this model, the relationships among the damage power, damage energy, pulse width and signal amplitude are investigated. Simulation results show that the pulse width index from the damage power formula obtained here is higher than that from the empirical formula due to the hotspot transferring in the damage process of the device. It is observed that the damage energy is not a constant, which decreases with the signal amplitude increasing, and then changes little when the signal amplitude reaches up to a certain level. Project supported by the National Basic Research Program of China (Grant No. 2014CB339900) and the Open Fund of Key Laboratory of Complex Electromagnetic Environment Science and Technology, China Academy of Engineering Physics (CAEP) (Grant No. 2015-0214.XY.K).

  11. The effects of lightning and high altitude electromagnetic pulse on power distribution lines

    Energy Technology Data Exchange (ETDEWEB)

    Uman, M.A.; Rubinstein, M.; Yacoub, Z. [Florida Univ., Gainesville, FL (United States)

    1995-01-01

    We simultaneously recorded the voltages induced by lightning on both ends of an unenergized 448-meter long unenergized electric power line and the lightning vertical electric and horizontal magnetic fields at ground level near the line. The lightning data studied and presented here were due both to cloud lightning and to very close (about 20 m from the line) artificially initiated lightning. For cloud sources, a frequency-domain computer program called EMPLIN was used to calculate induced line voltages as a function of source elevation, angle of incidence, and wave polarization of the radiated cloud discharge pulses in order to compare with the measurements. For very-close lightning, the measured line voltages could be grouped into two categories, those in which multiple, similarly shaped, evenly spaced pulses were observed, which we call oscillatory, and those dominated by a principal pulse with subsidiary oscillations of much smaller amplitude, which we call impulsive. The amplitude of the induced voltage ranged from tens of kilovolts for oscillatory voltages to hundreds of kilovolts for impulsive voltages. A new technique is derived for the calculation of the electromagnetic fields from nearby lightning to ground above an imperfectly conducting ground. This technique was used in conjunction with an existing time domain coupling theory and lightning return stroke model to calculate voltages at either end of the line. The results show fair agreement with the measured oscillatory voltage waveforms if corona is ignored and improved results when corona effects are modeled. The modeling of the impulsive voltage, for which local flashover probably successful. In an attempt to understand better the sources of the line voltages for very close lightning, measurements of the horizontal and vertical electric fields 30 m from triggered lightning were obtained.

  12. Propagation of two short laser pulse trains in a $\\Lambda$-type three-level medium under conditions of electromagnetically induced transparency

    CERN Document Server

    Buica, Gabriela

    2014-01-01

    We investigate the dynamics of a pair of short laser pulse trains propagating in a medium consisting of three-level $\\Lambda$-type atoms by numerically solving the Maxwell-Schr\\"odinger equations for atoms and fields. By performing propagation calculations with different parameters, under conditions of electromagnetically induced transparency, we compare the propagation dynamics by a single pair of probe and coupling laser pulses and by probe and coupling laser pulse trains. We discuss the influence of the coupling pulse area, number of pulses, and detunings on the probe laser propagation and realization of electromagnetically induced transparency conditions, as well on the formation of a dark state.

  13. Electromagnetism applications in nuclear engineering: cyclotron; Aplicacoes do eletromagnetismo na engenharia nuclear; ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Nobrega Bastos; Dalla Riva, Maria Teresa Cristina da

    1995-08-01

    Particle accelerators, with special emphasis on cyclotrons, are presented. Other electromagnetic devices and their importance in technology and research are also shown. An experimental arrangement for positrons source productions using a cyclotron aiming at non-destructive testing for radiations damage studies is presented. 46 refs., 23 figs., 2 tabs.

  14. A randomized double-blind prospective study of the efficacy of pulsed electromagnetic fields for interbody lumbar fusions

    Energy Technology Data Exchange (ETDEWEB)

    Mooney, V. (Univ. of California, Irvine (USA))

    1990-07-01

    A randomized double-blind prospective study of pulsed electromagnetic fields for lumbar interbody fusions was performed on 195 subjects. There were 98 subjects in the active group and 97 subjects in the placebo group. A brace containing equipment to induce an electromagnetic field was applied to patients undergoing interbody fusion in the active group, and a sham brace was used in the control group. In the active group there was a 92% success rate, while the control group had a 65% success rate (P greater than 0.005). The effectiveness of bone graft stimulation with the device is thus established.

  15. Effect of intervention initiation timing of pulsed electromagnetic field on ovariectomy-induced osteoporosis in rats.

    Science.gov (United States)

    Zhou, Jun; Liao, Yuan; Zeng, Yahua; Xie, Haitao; Fu, Chengxiao; Li, Neng

    2017-09-01

    The aim of this study is to explore the effect of timing of initiation of pulsed electromagnetic field (PEMF) therapy on bone mass, microarchitecture, and biomechanical properties, and to investigate receptor activator of NF-kB (RANK) expression in ovariectomized (OVX) rats. Sixty female Sprague-Dawley rats were randomly divided into two equal batches of three groups each (10 rats in each group). The first batch comprised of sham-operated (Sham-0 group), ovariectomized (OVX-0 group), and ovariectomized plus treated with PEMF starting from the day of OVX (Early PEMF group). The second batch comprised of sham-operated (Sham-12 group), ovariectomized (OVX-12 group), and ovariectomized plus treated with PEMF starting 12 weeks after OVX (Late PEMF group). Rats (whole body) in the early and late PEMF groups were exposed to PEMF (3.8 mT peak, 8 Hz pulse burst repetition rate). After 12 weeks of PEMF therapy, Early PEMF prevented OVX-induced deterioration in bone mineral density (BMD) and mechanical properties in lumbar vertebral body and femur, and deterioration in bone microarchitecture in lumbar vertebral body and proximal tibia. Late PEMF intervention only inhibited deterioration of BMD, bone microarchitecture, and mechanical properties in lumbar vertebral body. Both early and late PEMF therapy suppressed RANK protein expression in OVX rats without a concomitant effect on RANK mRNA expression. These results demonstrate that timing of initiation of PEMF therapy plays an important role in achieving optimal beneficial effects. The specific PEMF parameters may exert these favorable biological responses, at least partially, via inhibition of protein expression of RANK. Bioelectromagnetics. 38:456-465, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Simulations of Radioactive Decays: an Application of Low-Energy Electromagnetic Packages for the Nuclear Medicine

    Directory of Open Access Journals (Sweden)

    Munkhbaatar Batmunkh

    2015-12-01

    Full Text Available Problems of the radiobiology and the nuclear medicine require clarifying the specifi cs of radionuclides interactions with unhealthy cells. In this work we aimed to simulate emitting particles tracks of radionuclides and their radioactive decays at DNA level inside the cell nucleus. Accordingly, using the Monte Carlo-based track structure simulation technique, we estimated the radial distribution of deposited energy and kinetic energy spectra of electrons produced by primary particles resulting from radioactive decays of diff erent radionuclides within cell nucleus. To address the possibility of DNA damage, we performed the cluster analysis of track structures of emitted particles inside the volumes corresponding to the size of the native double-stranded DNA. For this purpose, G4-RadioactiveDecay and low- energy electromagnetic packages form Geant4 Monte-Carlo toolkit were combined together. Besides, a comparative analysis was performed for various low-energy electromagnetic packages as G4-DNA and G4-Livermore

  17. Pulsed Electromagnetic Field with Temozolomide Can Elicit an Epigenetic Pro-apoptotic Effect on Glioblastoma T98G Cells.

    Science.gov (United States)

    Pasi, Francesca; Fassina, Lorenzo; Mognaschi, Maria Evelina; Lupo, Giuseppe; Corbella, Franco; Nano, Rosanna; Capelli, Enrica

    2016-11-01

    Treatment with pulsed electromagnetic fields (PEMFs) is emerging as an interesting therapeutic option for patients with cancer. The literature has demonstrated that low-frequency/low-energy electromagnetic fields do not cause predictable effects on DNA; however, they can epigenetically act on gene expression. The aim of the present work was to study a possible epigenetic effect of a PEMF, mediated by miRNAs, on a human glioblastoma cell line (T98G). We tested a PEMF (maximum magnetic induction, 2 mT; frequency, 75 Hz) that has been demonstrated to induce autophagy in glioblastoma cells. In particular, we studied the effect of PEMF on the expression of genes involved in cancer progression and a promising synergistic effect with temozolomide, a frequently used drug to treat glioblastoma multiforme. We found that electromagnetic stimulation in combination with temozolomide can elicit an epigenetic pro-apoptotic effect in the chemo- and radioresistant T98G glioblastoma cell line.

  18. [Pulse-modulated Electromagnetic Radiation of Extremely High Frequencies Protects Cellular DNA against Damaging Effect of Physico-Chemical Factors in vitro].

    Science.gov (United States)

    Gapeyev, A B; Lukyanova, N A

    2015-01-01

    Using a comet assay technique, we investigated protective effects of. extremely high frequency electromagnetic radiation in combination with the damaging effect of X-ray irradiation, the effect of damaging agents hydrogen peroxide and methyl methanesulfonate on DNA in mouse whole blood leukocytes. It was shown that the preliminary exposure of the cells to low intensity pulse-modulated electromagnetic radiation (42.2 GHz, 0.1 mW/cm2, 20-min exposure, modulation frequencies of 1 and 16 Hz) caused protective effects decreasing the DNA damage by 20-45%. The efficacy of pulse-modulated electromagnetic radiation depended on the type of genotoxic agent and increased in a row methyl methanesulfonate--X-rays--hydrogen peroxide. Continuous electromagnetic radiation was ineffective. The mechanisms of protective effects may be connected with an induction of the adaptive response by nanomolar concentrations of reactive oxygen species formed by pulse-modulated electromagnetic radiation.

  19. UTILIZATION OF PULSED ELECTROMAGNETIC FIELD AND TRADITIONAL PHYSIOTHERAPY IN KNEE OSTEOARTHRITIS MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Kadrya H. Battecha

    2015-04-01

    Full Text Available Background and Objectives: Pulsed electromagnetic field (PEMF has been suggested as a treatment method for musculoskeletal system disorders. The present study was conducted to determine whether the addition of PEMF to traditional physiotherapy produces better clinical outcomes than traditional physiotherapy alone in the management of moderate knee osteoarthritis (OA. Design: A single-blinded, randomized controlled study Methods: Twenty subjects (5 men and 15 women with unilateral moderate knee OA (Kellgren-Lawrence criteria grade 2. They were randomly allocated in 2 groups to receive: group (A PEMF plus ultrasound plus exercises; or (B ultrasound plus exercises. Both groups received the respective treatments 3 times per week for 4 weeks and underwent the same pretreatment and post treatment evaluation that included active knee range of motion (ROM by universal goniometer, knee pain score by visual analogue scale (VAS and knee functional performance by Western Ontario and McMaster Universities osteoarthritis index (WOMAC. Result: There was an improvement in both groups in active knee flexion ROM, reduced VAS score and improved WOMAC index , however, all outcomes were significantly better in group (A (p <0.05. Moreover, the percentages of outcomes improvement were in favor of group (A. Conclusion: The addition of PEMF to traditional physiotherapy in managing Knee OA produced a greater improvement in pain relief, range of motion and resulted in better functional performance than did traditional physiotherapy alone. The improvement in current study should be limited to short term outcomes of PEMF.

  20. Circadian Rhythm Influences the Promoting Role of Pulsed Electromagnetic Fields on Sciatic Nerve Regeneration in Rats

    Science.gov (United States)

    Zhu, Shu; Ge, Jun; Liu, Zhongyang; Liu, Liang; Jing, Da; Ran, Mingzi; Wang, Meng; Huang, Liangliang; Yang, Yafeng; Huang, Jinghui; Luo, Zhuojing

    2017-01-01

    Circadian rhythm (CR) plays a critical role in the treatment of several diseases. However, the role of CR in the treatment of peripheral nerve defects has not been studied. It is also known that the pulsed electromagnetic fields (PEMF) can provide a beneficial microenvironment to quicken the process of nerve regeneration and to enhance the quality of reconstruction. In this study, we evaluate the impact of CR on the promoting effect of PEMF on peripheral nerve regeneration in rats. We used the self-made “collagen-chitosan” nerve conduits to bridge the 15-mm nerve gaps in Sprague-Dawley rats. Our results show that PEMF stimulation at daytime (DPEMF) has most effective outcome on nerve regeneration and rats with DPEMF treatment achieve quickly functional recovery after 12 weeks. These findings indicate that CR is an important factor that determines the promoting effect of PEMF on peripheral nerve regeneration. PEMF exposure in the daytime enhances the functional recovery of rats. Our study provides a helpful guideline for the effective use of PEMF mediations experimentally and clinically. PMID:28360885

  1. Enhanced skin permeation of naltrexone by pulsed electromagnetic fields in human skin in vitro.

    Science.gov (United States)

    Krishnan, Gayathri; Edwards, Jeffrey; Chen, Yan; Benson, Heather A E

    2010-06-01

    The aim of the present study was to evaluate the skin permeation of naltrexone (NTX) under the influence of a pulsed electromagnetic field (PEMF). The permeation of NTX across human epidermis and a silicone membrane in vitro was monitored during and after application of the PEMF and compared to passive application. Enhancement ratios of NTX human epidermis permeation by PEMF over passive diffusion, calculated based on the AUC of cumulative NTX permeation to the receptor compartment verses time for 0-4 h, 4-8 h, and over the entire experiment (0-8 h) were 6.52, 5.25, and 5.66, respectively. Observation of the curve indicated an initial enhancement of NTX permeation compared to passive delivery whilst the PEMF was active (0-4 h). This was followed by a secondary phase after termination of PEMF energy (4-8 h) in which there was a steady increase in NTX permeation. No significant enhancement of NTX penetration across silicone membrane occurred with PEMF application in comparison to passively applied NTX. In a preliminary experiment PEMF enhanced the penetration of 10 nm gold nanoparticles through the stratum corneum as visualized by multiphoton microscopy. This suggests that the channels through which the nanoparticles move must be larger than the 10 nm diameter of these rigid particles.

  2. Pulsed electromagnetic fields (PEMF) promote early wound healing and myofibroblast proliferation in diabetic rats.

    Science.gov (United States)

    Cheing, Gladys Lai-Ying; Li, Xiaohui; Huang, Lin; Kwan, Rachel Lai-Chu; Cheung, Kwok-Kuen

    2014-04-01

    Reduced collagen deposition possibly leads to slow recovery of tensile strength in the healing process of diabetic cutaneous wounds. Myofibroblasts are transiently present during wound healing and play a key role in wound closure and collagen synthesis. Pulsed electromagnetic fields (PEMF) have been shown to enhance the tensile strength of diabetic wounds. In this study, we examined the effect of PEMF on wound closure and the presence of myofibroblasts in Sprague-Dawley rats after diabetic induction using streptozotocin. A full-thickness square-shaped dermal wound (2 cm × 2 cm) was excised aseptically on the shaved dorsum. The rats were randomly divided into PEMF-treated (5 mT, 25 Hz, 1 h daily) and control groups. The results indicated that there were no significant differences between the groups in blood glucose level and body weight. However, PEMF treatment significantly enhanced wound closure (days 10 and 14 post-wounding) and re-epithelialization (day 10 post-wounding), although these improvements were no longer observed at later stages of the wound healing process. Using immunohistochemistry against α-smooth muscle actin (α-SMA), we demonstrated that significantly more myofibroblasts were detected on days 7 and 10 post-wounding in the PEMF group when compared to the control group. We hypothesized that PEMF would increase the myofibroblast population, contributing to wound closure during diabetic wound healing.

  3. The Effects of Pulsed Electromagnetic Field in the Treatment of Osteoarthritis in Dogs: Clinical Study

    Directory of Open Access Journals (Sweden)

    Stefania Pinna*§, Francesca Landucci§, Anna Maria Tribuiani§, Fabio Carli and Antonio Venturini

    2013-01-01

    Full Text Available In this study the effects of pulsed electromagnetic field (PEMF on pain relief and functional capacity of dogs with osteoarthritis (OA were investigated, and compared with firocoxib. Patients were randomly assigned to two groups: twenty-five client-owned dogs were treated with PEMF once a day for 20 sessions, and fifteen dogs (control group were treated with 5 mg/kg of firocoxib once daily for 20 days. Blinded clinical examination and owner’s assessment were recorded before and after the therapy, as well as 4 and 12 months later. Data collections were statistically compared before and after treatments and between groups. Both groups showed decreased clinical signs of OA during the treatment. Compared with baseline, these improvements were statistically significant (P<0.01 during the therapies. Differences were recorded during observation time spans following the end of treatments. In the PEMF group the effects were sustained until the end of the study, whereas in the control group the progress tended to return to baseline values after the end of therapy. The beneficial effects of PEMF on pain relief and functional capacity make it a potential treatment modality for canine osteoarthritis compared to traditional pharmacological therapy, in absence of adverse effects and in favour of the quality of life.

  4. Neuroprotective Effect of Low Frequency-Pulsed Electromagnetic Fields in Ischemic Stroke.

    Science.gov (United States)

    Urnukhsaikhan, Enerelt; Mishig-Ochir, Tsogbadrakh; Kim, Soo-Chan; Park, Jung-Keug; Seo, Young-Kwon

    2017-04-01

    Low frequency-pulsed electromagnetic fields (LF-PEMFs) affect many biological processes; however, the fundamental mechanisms responsible for these effects remain unclear. Our study aimed to investigate the effect of LF-PEMFs on neuroprotection after ischemic stroke. C57B6 mice were exposed to LF-PEMF (F = 60 Hz, Bm = 10 mT) after photothrombotic occlusion. We measured the BDNF/TrkB/Akt signaling pathway, pro-apoptotic and pro-survival protein and gene expressions, and the expression of inflammatory mediators and performed behavioral tests in both LF-PEMF-treated and untreated ischemic stroke mice. Our results showed that LF-PEMF treatment promotes activation of the BDNF/TrkB/Akt signaling pathway. Subsequently, pro-survival proteins were significantly increased, while pro-apoptotic proteins and inflammatory mediators were decreased in ischemic stroke mice after LF-PEMF treatment. The results demonstrated that LF-PEMF exposure has a neuroprotective effect after ischemic stroke in mice during the recovery process.

  5. Electromagnetic Pulses Generated From Laser Target Interactions at Shenguang II Laser Facility

    Science.gov (United States)

    Yang, Jinwen; Li, Tingshuai; Yi, Tao; Wang, Chuanke; Yang, Ming; Yang, Weiming; Liu, Shenye; Jiang, Shaoen; Ding, Yongkun

    2016-10-01

    Significant electromagnetic pulses (EMP) can be generated by the intensive laser irradiating solid targets in inertial confinement fusion (ICF). To evaluate the EMP intensity and distribution in and outside the laser chamber, we designed and fabricated a discone antenna with ultra-wide bands of over 10 GHz. The return loss (S11 parameter) of this antenna was below -10 dB and could even achieve under -30 dB at 3.1 GHz. The EMP intensity in this study at 80 cm and 40 cm away from the target chamber center (TCC) reached 400 kV/m and 2000 kV/m. The current results are expected to offer preliminary information to study physics regarding laser plasma interactions and will also lay experimental foundation for EMI shielding design to protect various diagnostics. supported by the Fundamental Research Funds for the Central Universities of China (No. ZYGX2015J108) and National Natural Science Foundation of China (Nos. 11575166 and 51581140)

  6. In vivo effect of two different pulsed electromagnetic field frequencies on osteoarthritis.

    Science.gov (United States)

    Veronesi, F; Torricelli, P; Giavaresi, G; Sartori, M; Cavani, F; Setti, S; Cadossi, M; Ongaro, A; Fini, M

    2014-05-01

    Osteoarthritis (OA) is a joint pathology characterized by fibrillation, reduced cartilage thickness and subchondral bone sclerosis. There is evidence that pulsed electromagnetic fields (PEMFs) counteract OA progression, but the effect of two different PEMF frequencies has not yet been shown. The aim of this study was to test the effectiveness of PEMFs at two different frequencies (37 and 75 Hz) in a late OA stage in 21-month-old Guinea pigs. After 3 months of 6 h/day PEMF stimulation, histological and histomorphometric analyses of the knees were performed. At both frequencies, PEMFs significantly reduced histological cartilage score, fibrillation index (FI), subchondral bone thickness (SBT) and trabecular number (Tb.N) and increased trabecular thickness (Tb.Th) and separation (Tb.Sp) in comparison to the not treated SHAM group. However, PEMFs at 75 Hz produced significantly more beneficial effects on the histological score and FI than 37 Hz PEMFs. At 75 Hz, PEMFs counteracted cartilage thinning as demonstrated by a significantly higher cartilage thickness values than either those of the SHAM or 37 Hz PEMF-treated groups. Although in severe OA both PEMF frequencies were able to limit its progression, 75 Hz PEMF stimulation achieved the better results.

  7. Pulsed electromagnetic field treatment enhances healing callus biomechanical properties in an animal model of osteoporotic fracture.

    Science.gov (United States)

    Androjna, Caroline; Fort, Brian; Zborowski, Maciej; Midura, Ronald J

    2014-09-01

    Delayed bone healing has been noted in osteoporosis patients and in the ovariectomized (OVX) rat model of estrogen-depletion osteopenia. Pulsed electromagnetic field (PEMF) devices are clinically approved as an adjunct to cervical fusion surgery in patients at high risk for non-fusion and for the treatment of fracture non-unions. These bone growth stimulating devices also accelerate the healing of fresh fracture repair in skeletally mature normal rats but have not been tested for efficacy to accelerate and/or enhance the delayed bone repair process in OVX rats. The current study tested the hypothesis that daily PEMF treatments would improve the fracture healing response in skeletally mature OVX rats. By 6 weeks of healing, PEMF treatments resulted in improved hard callus elastic modulus across fibula fractures normalizing the healing process in OVX rats with respect to this mechanical property. Radiographic evidence showed an improved hard callus bridging across fibula fractures in OVX rats treated with PEMF as compared to sham treatments. These findings provide a scientific rationale for investigating whether PEMF might improve bone-healing responses in at-risk osteoporotic patients.

  8. EMPulse, a new 3-D simulation code for electromagnetic pulse studies

    Science.gov (United States)

    Cohen, Bruce; Eng, Chester; Farmer, William; Friedman, Alex; Grote, David; Kruger, Hans; Larson, David

    2016-10-01

    EMPulse is a comprehensive and modern 3-D simulation code for electro-magnetic pulse (EMP) formation and propagation studies, being developed at LLNL as part of a suite of codes to study E1 EMP originating from prompt gamma rays. EMPulse builds upon the open-source Warp particle-in-cell code framework developed by members of this team and collaborators at other institutions. The goal of this endeavor is a new tool enabling the detailed and self-consistent study of multi-dimensional effects in geometries that have typically been treated only approximately. Here we present an overview of the project, the models and methods that have been developed and incorporated into EMPulse, tests of these models, comparisons to simulations undertaken in CHAP-lite (derived from the legacy code CHAP due to C. Longmire and co-workers), and some approaches to increased computational efficiency being studied within our project. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Security, LLC, Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  9. Pulsed electromagnetic fields on postmenopausal osteoporosis in Southwest China: a randomized, active-controlled clinical trial.

    Science.gov (United States)

    Liu, Hui-Fang; Yang, Lin; He, Hong-Chen; Zhou, Jun; Liu, Ying; Wang, Chun-Yan; Wu, Yuan-Chao; He, Cheng-Qi

    2013-05-01

    A randomized, active-controlled clinical trial was conducted to examine the effect of pulsed electromagnetic fields (PEMFs) on women with postmenopausal osteoporosis (PMO) in southwest China. Forty-four participants were randomly assigned to receive alendronate or one course of PEMFs treatment. The primary endpoint was the mean percentage change in bone mineral density of the lumbar spine (BMDL), and secondary endpoints were the mean percentage changes in left proximal femur bone mineral density (BMDF), serum 25OH vitamin D3 (25(OH)D) concentrations, total lower-extremity manual muscle test (LE MMT) score, and Berg Balance Scale (BBS) score. The BMDL, BMDF, total LE MMT score and BBS score were recorded at baseline, 5, 12, and 24 weeks. Serum concentrations of 25(OH)D were measured at baseline and 5 weeks. Using a mixed linear model, there was no significant treatment difference between the two groups in the BMDL, BMDF, total LE MMT score, and BBS score (P ≥ 0.05). For 25(OH)D concentrations, the effects were also comparable between the two groups (P ≥ 0.05) with the Mann-Whitney's U-test. These results suggested that a course of PEMFs treatment with specific parameters was as effective as alendronate in treating PMO within 24 weeks.

  10. Femoral perfusion after pulsed electromagnetic field stimulation in a steroid-induced osteonecrosis model.

    Science.gov (United States)

    Ikegami, Akira; Ueshima, Keiichiro; Saito, Masazumi; Ikoma, Kazuya; Fujioka, Mikihiro; Hayashi, Shigeki; Ishida, Masashi; Fujiwara, Hiroyoshi; Mazda, Osam; Kubo, Toshikazu

    2015-07-01

    This study was designed to evaluate femoral perfusion after pulsed electromagnetic field (PEMF) stimulation in a steroid-induced osteonecrosis rabbit model by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Steroid-induced osteonecrosis was produced by single intramuscular injection of methylprednisolone in 15 rabbits. Eight rabbits underwent PEMF stimulation (PEMF group) and seven did not (control group). DCE-MRI was performed before PEMF stimulation, immediately before steroid administration, and 1, 5, 10, and 14 days after steroid administration. Regions of interest were set in the bilateral proximal femora. Enhancement ratio (ER), initial slope (IS), and area under the curve (AUC) were analyzed. ER, IS, and AUC in the control group significantly decreased after steroid administration compared with before administration (P<0.05). In PEMF group, IS significantly decreased; however, ER and AUC showed no significant differences after steroid administration compared with before. ER and IS in PEMF group were higher than in control group until 10th day, and AUC was higher until 5th day after steroid administration (P<0.05). PEMF stimulation restrains the decrease in blood flow after steroid administration.

  11. Preventing Electromagnetic Pulse Irradiation Damage on Testis Using Selenium-rich Cordyceps Fungi. A Preclinical Study in Young Male Mice.

    Science.gov (United States)

    Miao, Xia; Wang, Yafeng; Lang, Haiyang; Lin, Yanyun; Guo, Qiyan; Yang, Mingjuan; Guo, Juan; Zhang, Yanjun; Zhang, Jie; Liu, Junye; Liu, Yaning; Zeng, Lihua; Guo, Guozhen

    2017-02-01

    Networked 21st century society, globalization, and communications technologies are paralleled by the rise of electromagnetic energy intensity in our environments and the growing pressure of the environtome on human biology and health. The latter is the entire complement of environmental factors, including the electromagnetic energy and the technologies that generate them, enacting on the digital citizen in the new century. Electromagnetic pulse (EMP) irradiation might have serious damaging effects not only on electronic equipment but also in the whole organism and reproductive health, through nonthermal effects and oxidative stress. We sought to determine whether EMP exposure (1) induces biological damage on reproductive health and (2) the extent to which selenium-rich Cordyceps fungi (daily coadministration) offer protection on the testicles and spermatozoa. In a preclinical randomized study, 3-week-old male BALB/c mice were repeatedly exposed to EMP (peak intensity 200 kV/m, pulse edge 3.5 ns, pulse width 15 ns, 0.1 Hz, and 400 pulses/day) 5 days per week for four consecutive weeks, with or without coadministration of daily selenium-rich Cordyceps fungi (100 mg/kg). Testicular index and spermatozoa formation were measured at baseline and 1, 7, 14, 28, and 60 day time points after EMP exposure. The group without Cordyceps cotreatment displayed decreased spermatozoa formation, shrunk seminiferous tubule diameters, and diminished antioxidative capacity at 28 and 60 days after exposure (p < 0.05). The Cordyceps daily cotreatment alleviated the testicular damage by EMP exposure, increased spermatozoa formation, and reduced apoptotic spermatogenic cells. These observations warrant further preclinical and clinical studies as an innovative approach for potential protection against electromagnetic radiation in the current age of networked society and digital citizenship.

  12. Long Wavelength Electromagnetic Light Bullets Generated by a 10.6 micron CO2 Ultrashort Pulsed Source

    Science.gov (United States)

    2016-11-29

    GRANT NUMBER FA9550-15-1-0272 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Dr . Jerome V. Moloney, Professor of Optical Sciences University of Arizona...afosr.reports.sgizmo.com/s3/> Subject: Final Report to Dr . Arje Nachman Contract/Grant Title: Long Wavelength Electromagnetic Light Bullets Generated by a 10.6...kilometer ranges. Our in- house ultrashort pulse simulation tool was used to provide basic research support for studying atmospheric propagation of a

  13. Electromagnetism

    CERN Document Server

    Grant, Ian S

    1990-01-01

    The Manchester Physics Series General Editors: D. J. Sandiford; F. Mandl; A. C. Phillips Department of Physics and Astronomy, University of Manchester Properties of Matter B. H. Flowers and E. Mendoza Optics Second Edition F. G. Smith and J. H. Thomson Statistical Physics Second Edition F. Mandl Electromagnetism Second Edition I. S. Grant and W. R. Phillips Statistics R. J. Barlow Solid State Physics Second Edition J. R. Hook and H. E. Hall Quantum Mechanics F. Mandl Particle Physics Second Edition B. R. Martin and G. Shaw the Physics of Stars Second Edition A. C. Phillips Computing for Scient

  14. Electromagnetic properties of inner double walled carbon nanotubes investigated by nuclear magnetic resonance

    KAUST Repository

    Bouhrara, M.

    2013-01-01

    The nuclear magnetic resonance (NMR) analytical technique was used to investigate the double walled carbon nanotubes (DWNTs) electromagnetic properties of inner walls. The local magnetic and electronic properties of inner nanotubes in DWNTs were analyzed using 25% 13C enriched C 60 by which the effect of dipolar coupling could be minimized. The diamagnetic shielding was determined due to the ring currents on outer nanotubes in DWNTs. The NMR chemical shift anisotropy (CSA) spectra and spin-lattice relaxation studies reveal the metallic properties of the inner nanotubes with a signature of the spin-gap opening below 70 K.

  15. The therapeutic effect of a pulsed electromagnetic field on the reproductive patterns of male Wistar rats exposed to a 2.45-GHz microwave field

    OpenAIRE

    Sanjay Kumar; Kavindra Kumar Kesari; Jitendra Behari

    2011-01-01

    INTRODUCTION: Environmental exposure to man-made electromagnetic fields has been steadily increasing with the growing demand for electronic items that are operational at various frequencies. Testicular function is particularly susceptible to radiation emitted by electromagnetic fields. OBJECTIVES: This study aimed to examine the therapeutic effects of a pulsed electromagnetic field (100 Hz) on the reproductive systems of male Wistar rats (70 days old). METHODS: The experiments were divided in...

  16. Evaluation of the electromagnetic effects due to direct lighting to nuclear explosive areas at Pantex. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Merewether, K.O.; Chen, K.C.

    1993-11-01

    This report summarizes the effort to quantify the electromagnetic environments in the nuclear explosive areas at Pantex due to direct lightning. The fundamental measure of the threat to nuclear safety is assumed to be the maximum voltage between any two points in an assembly area, which is then available for producing arcing or for driving current into critical subsystems of a nuclear weapon. This maximum voltage has been computed with simple analytical models and with three-dimensional finite-difference computer codes.

  17. Pulse interactions in a quantum dot waveguide in the regime of electromagnetically Induced transparency

    DEFF Research Database (Denmark)

    Nielsen, Per; Nielsen, Henri; Mørk, Jesper;

    2006-01-01

    The interaction of optical pulses in a quantum dot waveguide in the slow-light regime is investigated. Dipole oscillations lead to strong interactions between the two pulses, implying a minimum pulse separation for optical buffer applications....

  18. Role of electron-nuclear coupled dynamics on charge migration induced by attosecond pulses in glycine

    Science.gov (United States)

    Lara-Astiaso, Manuel; Palacios, Alicia; Decleva, Piero; Tavernelli, Ivano; Martín, Fernando

    2017-09-01

    We present a theoretical study of charge dynamics initiated by an attosecond XUV pulse in the glycine molecule, which consists in delocalized charge fluctuations all over the molecular skeleton. For this, we have explicitly used the actual electron wave packet created by such a broadband pulse. We show that, for the chosen pulse, charge dynamics in glycine is barely affected by nuclear motion or non adiabatic effects during the first 8 fs, and that the initial electronic coherences do not dissipate during the first 20 fs. In contrast, small variations in the initial nuclear positions, compatible with the geometries expected in the Franck-Condon region, lead to noticeable changes in this dynamics.

  19. Stimulation of osteogenic differentiation in human osteoprogenitor cells by pulsed electromagnetic fields: an in vitro study

    Directory of Open Access Journals (Sweden)

    Jansen Justus HW

    2010-08-01

    Full Text Available Abstract Background Although pulsed electromagnetic field (PEMF stimulation may be clinically beneficial during fracture healing and for a wide range of bone disorders, there is still debate on its working mechanism. Mesenchymal stem cells are likely mediators facilitating the observed clinical effects of PEMF. Here, we performed in vitro experiments to investigate the effect of PEMF stimulation on human bone marrow-derived stromal cell (BMSC metabolism and, specifically, whether PEMF can stimulate their osteogenic differentiation. Methods BMSCs derived from four different donors were cultured in osteogenic medium, with the PEMF treated group being continuously exposed to a 15 Hz, 1 Gauss EM field, consisting of 5-millisecond bursts with 5-microsecond pulses. On culture day 1, 5, 9, and 14, cells were collected for biochemical analysis (DNA amount, alkaline phosphatase activity, calcium deposition, expression of various osteoblast-relevant genes and activation of extracellular signal-regulated kinase (ERK signaling. Differences between treated and control groups were analyzed using the Wilcoxon signed rank test, and considered significant when p Results Biochemical analysis revealed significant, differentiation stage-dependent, PEMF-induced differences: PEMF increased mineralization at day 9 and 14, without altering alkaline phosphatase activity. Cell proliferation, as measured by DNA amounts, was not affected by PEMF until day 14. Here, DNA content stagnated in PEMF treated group, resulting in less DNA compared to control. Quantitative RT-PCR revealed that during early culture, up to day 9, PEMF treatment increased mRNA levels of bone morphogenetic protein 2, transforming growth factor-beta 1, osteoprotegerin, matrix metalloproteinase-1 and -3, osteocalcin, and bone sialoprotein. In contrast, receptor activator of NF-κB ligand expression was primarily stimulated on day 14. ERK1/2 phosphorylation was not affected by PEMF stimulation

  20. Electromagnetic dissociation of 3.7 A GeV 16O in nuclear emulsion

    Institute of Scientific and Technical Information of China (English)

    Li Jun-Sheng; Zhang Dong-Hai; Li Zhen-Yu; Wu Feng-Juan

    2004-01-01

    The electromagnetic dissociation (ED) of 3.7A GeV 16O in nuclear emulsion is investigated with high statistics.It is found that the electromagnetically dissociated cross section increases with increasing beam energy, the charge distribution of projectile fragments is the same as the results at 60 and 200A GeV, and the production probability of projectile fragments with charge 3 ≤ Z ≤ 5 is less than that of the other projectile fragments. These results can be wellexplained by use of Weizsacker and Williams method for calculating the ED contributions. The percentile abundance of various decay modes for ED at 3.7 A GeV is close to the result at 60 and 200 A GeV, but it is different from the result at 14.6 A GeV. The ED of 3.7 A GeV is mainly caused by the giant dipole and quadrupole resonance of E1 and E2, which can be qualitatively explained by the multiplicity distribution of projectile proton in ED. The multiplicity distribution of the α fragments in ED and nuclear events have different functional forms. This difference may be a consequence of the different reaction mechanism involved.

  1. Pulsed Electromagnetic Field Exposure Reduces Hypoxia and Inflammation Damage in Neuron-Like and Microglial Cells.

    Science.gov (United States)

    Vincenzi, Fabrizio; Ravani, Annalisa; Pasquini, Silvia; Merighi, Stefania; Gessi, Stefania; Setti, Stefania; Cadossi, Ruggero; Borea, Pier Andrea; Varani, Katia

    2017-05-01

    In the present study, the effect of low-frequency, low-energy pulsed electromagnetic fields (PEMFs) has been investigated by using different cell lines derived from neuron-like cells and microglial cells. In particular, the primary aim was to evaluate the effect of PEMF exposure in inflammation- and hypoxia-induced injury in two different neuronal cell models, the human neuroblastoma-derived SH-SY5Y cells and rat pheochromocytoma PC12 cells and in N9 microglial cells. In neuron-like cells, live/dead and apoptosis assays were performed in hypoxia conditions from 2 to 48 h. Interestingly, PEMF exposure counteracted hypoxia damage significantly reducing cell death and apoptosis. In the same cell lines, PEMFs inhibited the activation of the hypoxia-inducible factor 1α (HIF-1α), the master transcriptional regulator of cellular response to hypoxia. The effect of PEMF exposure on reactive oxygen species (ROS) production in both neuron-like and microglial cells was investigated considering their key role in ischemic injury. PEMFs significantly decreased hypoxia-induced ROS generation in PC12, SH-SY5Y, and N9 cells after 24 or 48 h of incubation. Moreover, PEMFs were able to reduce some of the most well-known pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-8 release in N9 microglial cells stimulated with different concentrations of LPS for 24 or 48 h of incubation time. These results show a protective effect of PEMFs on hypoxia damage in neuron-like cells and an anti-inflammatory effect in microglial cells suggesting that PEMFs could represent a potential therapeutic approach in cerebral ischemic conditions. J. Cell. Physiol. 232: 1200-1208, 2017. © 2016 Wiley Periodicals, Inc.

  2. Efficacy of pulsed electromagnetic field therapy in healing of pressure ulcers: A randomized control trial

    Directory of Open Access Journals (Sweden)

    Gupta Anupam

    2009-12-01

    Full Text Available Background : Pressure ulcers are one of the most common complications in health care settings. Still there are no optimal protocols to manage the pressure ulcers. Aim : To assess the effectiveness of pulsed electromagnetic field therapy (PEMF in healing of pressure ulcers in patients with neurological disorders. Design : Randomized double blind control trial. Setting : Neurological rehabilitation department in a university research hospital. Participants : Twelve patients (M:F, 9:3 having neurological disorders, with age between 12-50 years (mean 30.16611.32 yrs and 24 pressure ulcers. Intervention : Six patients with 13 ulcers received PEMF therapy and the remaining 6 patients with 11 ulcers received sham treatment, for 30 sessions (45 minutes each using the equipment ′Pulsatron′. The frequency of PEMF was set at 1 Hz with sine waves and current intensity of 30 mili ampere. Whole body exposure was given in both the groups. Outcome Measures : Bates-Jensen wound assessment tool (BJWAT score was used as main outcome measure and scores at the end of session were compared with initial scores and analyzed. Similarly National Pressure Ulcer Advisory Panel (NPUAP scores were compared and analyzed as secondary outcome measure. Results : Thirteen ulcers were in stage IV and 11 were in stage III at the start of the study. Significant healing of ulcers was noted, BJWAT scores, in both the treatment and sham groups (P < 0.001 and 0.003 respectively at the completion of the study. However, when comparing between the groups, healing was not significant (P = 0.361. Similarly trend was noted with NPUAP scores with no significant difference between the treatment and sham groups (P = 0.649 at the completion of study. Conclusions : No significant difference in pressure ulcer healing was observed between PEMF treatment and sham group in this study.

  3. 76 FR 13397 - DOE Response to Recommendation 2010-2 of the Defense Nuclear Facilities Safety Board, Pulse Jet...

    Science.gov (United States)

    2011-03-11

    ... Response to Recommendation 2010-2 of the Defense Nuclear Facilities Safety Board, Pulse Jet Mixing at the... Defense Nuclear Facilities Safety Board Recommendation 2010-2, concerning Pulse Jet Mixing at the Waste... Board (Board) Recommendation 2010-2, Pulse Jet Mixing at the Waste Treatment and Immobilization...

  4. The electromagnetic radiation fields of a relativistic electron avalanche with special attention to the origin of narrow bipolar pulses

    Science.gov (United States)

    Cooray, G. V.; Cooray, G. K.

    2011-12-01

    Gurevich et al. [1] postulated that the source of narrow bipolar pulses, a class of high energy pulses that occur during thunderstorms, could be a runaway electron avalanche driven by the intense electric fields of a thunderstorm. Recently, Watson and Marshall [2] used the modified transmission line model to test the mechanism of the source of narrow bipolar pulses. In a recent paper, Cooray and Cooray [3] demonstrated that the electromagnetic fields of accelerating charges could be used to evaluate the electromagnetic fields from electrical discharges if the temporal and spatial variation of the charges in the discharge is known. In the present study, those equations were utilized to evaluate the electromagnetic fields generated by a relativistic electron avalanche. In the analysis it is assumed that all the electrons in the avalanche are moving with the same speed. In other words, the growth or the decay of the number of electrons takes place only at the head of the avalanche. It is shown that the radiation is emanating only from the head of the avalanche where electrons are being accelerated. It is also shown that an analytical expression for the radiation field of the avalanche at any distance can be written directly in terms of the e-folding length of the avalanche. This makes it possible to extract directly the spatial variation of the e-folding length of the avalanche from the measured radiation fields. In the study this model avalanche was used to investigate whether it can be used to describe the measured electromagnetic fields of narrow bipolar pulses. The results obtained are in reasonable agreement with the two station data of Eack [4] for speeds of propagation around (2 - 2.5) x 10^8 m/s and when the propagation effects on the electric fields measured at the distant station is taken into account. [1] Gurevich et al. (2004), Phys. Lett. A., 329, pp. 348 -361. [2] Watson, S. S. and T. C. Marshall (2007), Geophys. Res. Lett., Vol. 34, L04816, doi: 10

  5. Damage effect and mechanism of the GaAs pseudomorphic high electron mobility transistor induced by the electromagnetic pulse

    Science.gov (United States)

    Xiao-Wen, Xi; Chang-Chun, Chai; Gang, Zhao; Yin-Tang, Yang; Xin-Hai, Yu; Yang, Liu

    2016-04-01

    The damage effect and mechanism of the electromagnetic pulse (EMP) on the GaAs pseudomorphic high electron mobility transistor (PHEMT) are investigated in this paper. By using the device simulation software, the distributions and variations of the electric field, the current density and the temperature are analyzed. The simulation results show that there are three physical effects, i.e., the forward-biased effect of the gate Schottky junction, the avalanche breakdown, and the thermal breakdown of the barrier layer, which influence the device current in the damage process. It is found that the damage position of the device changes with the amplitude of the step voltage pulse. The damage appears under the gate near the drain when the amplitude of the pulse is low, and it also occurs under the gate near the source when the amplitude is sufficiently high, which is consistent with the experimental results. Project supported by the National Basic Research Program of China (Grant No. 2014CB339900), and the Open Fund of Key Laboratory of Complex Electromagnetic Environment Science and Technology, China Academy of Engineering Physics (CAEP) (Grant No. 2015-0214.XY.K).

  6. Effect of Higher Order Axial Electron Temperature on Self-Focusing of Electromagnetic Pulsed Beam in Collisional Plasma

    Institute of Scientific and Technical Information of China (English)

    夏雄平; 易林

    2012-01-01

    Effect of higher order axial electron temperature on self-focusing of electromagnetic pulsed beam in collisional plasma is investigated.It is shown that higher order axial electron temperature T p4 is not trivial than T p0 and T p2,which can modify slightly radial redistribution of electron density and increases effective dielectric constant.As a result,on one hand,slightly reduce electromagnetic beam self-focusing in the course of oscillatory convergence,on the other hand,quicken beam divergence in the course of steady divergence,i.e.,higher order axial electron temperature T p4 can decrease the influence of collisional nonlinearity in collisional plasma.

  7. 脉冲电磁场与软骨代谢%Pulsed electromagnetic fields and cartilage metabolism

    Institute of Scientific and Technical Information of China (English)

    阮佳莉; 田京

    2013-01-01

      背景:目前研究已证实外周脉冲电磁场可以促进软骨代谢,但其分子水平机制仍不甚清楚。目的:探讨脉冲电磁场的物理特性及其在软骨形成方面的作用与机制。  方法:由第一作者应用计算机检索 PubMed、中国期刊全文数据库(CNKI)、维普数据库和万方数据库1997年5月至2012年8月有关脉冲电磁场对软骨代谢影响的文献。在标题、摘要、关键词中以“pulsed electromagnetic field(PEMFs),cartilage,bone marrow mesenchymal stem cel s(BMSCs)”或“脉冲电磁场,软骨代谢,软骨细胞,骨基质,骨髓间充质干细胞”为检索词进行检索。排除重复研究或内容较陈旧的文献。  结果与结论:初检得到145篇文献,排除99篇重复研究或内容较陈旧的文献,保留46篇文献进一步分析。结果显示,脉冲电磁场通过诱导骨髓间充质干细胞分化为软骨细胞,促进软骨特异性基质如Ⅱ型胶原及蛋白多糖的合成,从而发挥软骨诱导作用;脉冲电磁场通过促进转化生长因子β2与其他因子的表达,调节软骨细胞生长分化,使临床上永久性修复软骨组织缺损变为可能。%BACKGROUND:Peripheral pulsed electromagnetic fields have an obvious effect on cartilage metabolism;however, its molecular mechanism is stil unclear. OBJECTIVE:To investigate the physical characteristics of pulsed electromagnetic fields and its mechanism and effect on cartilage formation. METHODS:A computer-based online search of PubMed database, CNKI database, VIP database andWanfang database was performed to search related articles.“Pulsed electromagnetic fields, cartilage, cartilage cel s, matrix, bone marrow mesenchymal stem cel s”were used for word retrieval in the title, abstract, and keywords. Repetitive studies or old literatures were excluded. RESULTS AND CONCLUSION:A total of 145 articles were retrieved in the initial search, and final y 46

  8. Circuit-field coupled finite element analysis method for an electromagnetic acoustic transducer under pulsed voltage excitation

    Institute of Scientific and Technical Information of China (English)

    Hao Kuan-Sheng; Huang Song-Ling; Zhao Wei; Wang Shen

    2011-01-01

    This paper presents an analytical method for electromagnetic acoustic transducers (EMATs) under voltage excitation and considers the non-uniform distribution of the biased magnetic field. A complete model of EMATs including the non-uniform biased magnetic field, a pulsed eddy current field and the acoustic field is built up. The pulsed voltage excitation is transformed to the frequency domain by fast Fourier transformation (FFT). In terms of the time harmonic field equations of the EMAT system, the impedances of the coils under different frequencies are calculated according to the circuit-field coupling method and Poynting's theorem. Then the currents under different frequencies are calculated according to Ohm's law and the pulsed current excitation is obtained by inverse fast Fourier transformation (IFFT).Lastly, the sequentially coupled finite element method (FEM) is used to calculate the Lorentz force in the EMATs under the current excitation. An actual EMAT with a two-layer two-bundle printed circuit board (PCB) coil, a rectangular permanent magnet and an aluminium specimen is analysed. The coil impedances and the pulsed current are calculated and compared with the experimental results. Their agreement verified the validity of the proposed method. Furthermore, the influences of lift-off distances and the non-uniform static nagnetic field on the Lorentz force under pulsed voltage excitation are studied.

  9. Electromagnetic shielding. Citations from the NTIS data base

    Science.gov (United States)

    Reed, W. E.

    1980-06-01

    The bibliography presents research on electromagnetic shielding of electronic and electrical equipment personnel, and ordnance. The shielding effectiveness of materials and structures is covered. Nuclear electromagnetic pulse shielding is included. This updated bibliography contains 301 abstracts, 19 of which are new entries to the previous edition.

  10. 6th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions

    CERN Document Server

    2014-01-01

    One of the premier meetings in the field of high-energy nuclear physics, the Hard Probes conference series brings together the experimental and theoretical communities interested in the hard and electromagnetic observables related to nuclear matter at extreme temperatures and densities. Prior to the conference, the University of Cape Town will host a summer school for young physicists in the field. High energy nuclear physics focuses on the science of a trillion degrees. These temperatures were last seen in nature a microsecond after the Big Bang, but mankind recreates them thousands of times a second in particle accelerators such as CERN's Large Hadron Collider and BNL's Relativistic Heavy Ion Collider. At these temperatures, 100,000 times hotter than the center of the sun, the strong force is dominant, and we hope to learn about the fundamental and non-trivial emergent many-body dynamics of the quarks and gluons that make up 99% of the mass of the visible universe. We anticipate the usual format for the H...

  11. Pulse low-intensity electromagnetic field as prophylaxis of heterotopic ossification in patients with traumatic spinal cord injury

    Directory of Open Access Journals (Sweden)

    Đurović Aleksandar

    2009-01-01

    Full Text Available Background/Aim. Heterotopic ossification (HO is an important complication of head and spinal cord injuries (SCI. Pulse low-intensity electromagnetic field (PLIMF therapy increases blood flow to an area of pain or inflammation, bringing more oxygen to that area and helps to remove toxic substances. The aim of this study was to determine the effect of PLIMF as prophylaxis of HO in patients with SCI. Methods. This prospective random control clinical study included 29 patients with traumatic SCI. The patients were randomly divided into experimental (n = 14 and control group (n = 15. The patients in the experimental group, besides exercise and range of motion therapy, were treated by PLIMF of the following characteristics: induction of 10 mT, frequency of 25 Hz and duration of 30 min. Pulse low-intensity electromagnetic field therapy started in the 7th week after the injury and lasted 4 weeks. The presence or absence of HO around the patients hips we checked by a plane radiography and Brookers classification. Functional capabilities and motor impairment were checked by Functional Independent Measure (FIM, Barthel index and American Spinal Injury Association (ASIA impairment class. Statistic analysis included Kolmogorov-Smirnov test, Shapiro-Wilk test, Mann Whitney Exact test, Exact Wilcoxon signed rank test and Fischer Exact test. Statistical significance was set up to p < 0.05. Results. At the end of the treatment no patient from the experimental group had HO. In the control group, five patients (33.3% had HO. At the end of the treatment the majority of the patients from the experimental group (57.14% moved from ASIA-A to ASIA-B class. Conclusion. Pulse low-intensity electromagnetic field therapy could help as prophylaxis of HO in patients with traumatic SCI.

  12. Pulsed electromagnetic fields stimulation prevents steroid-induced osteonecrosis in rats

    Directory of Open Access Journals (Sweden)

    Zhou Jian-Lin

    2011-09-01

    Full Text Available Abstract Background Pulsed electromagnetic fields (PEMF stimulation has been used successfully to treat nonunion fractures and femoral head osteonecrosis, but relatively little is known about its effects on preventing steroid-induced osteonecrosis. The purpose of the study was to investigate the effects of PEMF stimulation on the prevention of steroid-induced osteonecrosis in rats and explore the underlying mechanisms. Methods Seventy-two male adult Wistar rats were divided into three groups and treated as follows. (1 PEMF stimulation group (PEMF group, n = 24: intravenously injected with lipopolysaccharide (LPS, 10 μg/kg on day 0 and intramuscularly injected with methylprednisolone acetate (MPSL, 20 mg/kg on days 1, 2 and 3, then subjected to PEMF stimulation 4 h per day for 1 to 8 weeks. (2 Methylprednisolone-treated group (MPSL group, n = 24: injected the same dose of LPS and MPSL as the PEMF group but without exposure to PEMF. (3 Control group (PS group, n = 24: injected 0.9% saline in the same mode at the same time points. The incidence of osteonecrosis, serum lipid levels and the mRNA and protein expression of transforming growth factor β1 (TGF-β1 in the proximal femur were measured 1, 2, 4 and 8 weeks after the last MPSL (or saline injection. Results The incidence of osteonecrosis in the PEMF group (29% was significantly lower than that observed in the MPSL group (75%, while no osteonecrosis was observed in the PS group. The serum lipid levels were significantly lower in the PEMF and PS groups than in the MPSL group. Compared with the MPSL and PS groups, the mRNA expression of TGF-β1 increased, reaching a peak 1 week after PEMF treatment, and remained high for 4 weeks, then declined at 8 weeks, whereas the protein expression of TGF-β1 increased, reaching a peak at 2 weeks after PEMF treatment, and remained high for 8 weeks. Conclusions PEMF stimulation can prevent steroid-induced osteonecrosis in rats, and the underlying mechanisms

  13. Research Internship on Pulse Electromagnetic Fields (PEMF) and Microwave Applications for Deep Space Exploration Medical Use

    Science.gov (United States)

    Hehir, Austin

    2016-01-01

    Throughout my internship, I worked under Dr. Diane Byerly on Pulse Electromagnetic Fields (PEMF) in the Biomedical Engineering for Exploration Space Technology Laboratory (BEEST). I conducted experiments and analyzed the impact coil size, placement, and contour have on flux densities. Using this information, I optimized coil configurations for future patient use. This was achieved by using a fiberglass leg casting and PEMF coils to evaluate the different flux densities produced at different locations on the leg. The fiberglass casting was an improvement on the prior test that used cylindrical tubing to determine the flux densities generated. The cast allowed for the natural bends of the leg to be taken into consideration in the experiment. Also, I investigated the impact that a Helmholtz coil configuration has on the flux densities produced in a leg. This configuration produces a constant magnetic field throughout the targeted area. This information supports the Helmholtz configuration for future medical testing using the PEMF technology being developed at JSC. A preliminary study using test subjects is scheduled for this summer at Methodist Hospital in Sugarland that will incorporate the data obtained from the tests I conducted to ensure accurate results. In addition, I supported the microwave laundry project for sanitizing clothes in space. I worked in the BEEST lab assisting in the preparation of bacterial inoculations and microwave testing to determine the efficacy of radiation on eradicating Staphylococcus aureus bacteria in inoculated fabric specimens. I performed S-band microwave tests to quantify the impact that increased layers of cloth and salt concentration have on both kill rate and temperature. NASA will use the information I obtained throughout my internship to aid in the design of a laundry enclosure system for the International Space Station. I also assisted in protocol development for the use of high frequency microwave energy for a number of

  14. Verification of electromagnetic effects from wireless devices in operating nuclear power plants

    Directory of Open Access Journals (Sweden)

    Song-Hae Ye

    2015-10-01

    Full Text Available Wireless communication technologies, especially smartphones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smartphones (Wi-Fi standard, Internet Protocol (IP phones, personal digital assistant (PDA for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs.

  15. Verification of electromagnetic effects from wireless devices in operating nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Song Hae; Kim, Young Sik; Lyou, Ho Sun; Kim, Min Suk [Korea Hydro and Nuclear Power Co. (KHNP), Central Research Institute, Daejeon (Korea, Republic of); Lyou, Joon [Dept. of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of)

    2015-10-15

    Wireless communication technologies, especially smart phones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs) because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smart phones (Wi-Fi standard), Internet Protocol (IP) phones, personal digital assistant (PDA) for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI) from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs.

  16. Evaluation of electromagnetic interference environment of the instrumentation and control systems in nuclear power units

    Energy Technology Data Exchange (ETDEWEB)

    Min, Moon-Gi; Lee, Jae-Ki; Ji, Yeong-Haw; Jo, Sung-Han [Korea Hydro & Nuclear Power Co., Ltd., 1312-70 Yuesong-daero, Yuseong-Gu, Daejeon 305-343 (Korea, Republic of); Kim, Hee-Je, E-mail: heeje@pusan.ac.kr [Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735 (Korea, Republic of)

    2015-04-15

    Highlights: • We surveyed the electromagnetic emissions at the location of I&C systems. • We assessed the electromagnetic levels on reactor types from thirteen nuclear plants. • We evaluated the margin between plant emission limits and the highest composite levels. • We presented the formula of radiated susceptibility test levels to non-safety-related I&C systems. - Abstract: The electromagnetic interference (EMI) generated from sources in power units can interfere with digital Instrument and Control (I&C) systems. When EMI is emitted with conducted and radiated noise, it interferes with the signals of the I&C systems. Since the digital I&C systems are efficient and competitively priced, the analogue I&C systems have been upgraded and replaced with digital I&C systems, but these systems have less EMI immunity. When safety-related I&C systems are installed in the units, the verification of equipment EMI should not be done in site-specific tests but in test facilities. There are needs to do the overall site-specific EMI assessment of I&C systems depending on the reactor types from thirteen operating units. This study evaluated the margin between plant emission limits and the highest composite plant emissions of the EMI. When the non-safety-related I&C equipment or systems are placed in the units, there are no individual test levels of the radiated electrical field. If need be, the level should comply with the test levels of the radiated electrical field on the safety-related I&C systems. This paper presents the test levels of radiated electrical fields to non-safety-related I&C equipment or systems.

  17. Application of chaotic pulse width modulation control for suppressing electromagnetic interference in a half-bridge converter

    Directory of Open Access Journals (Sweden)

    Yuhong Song

    2014-08-01

    Full Text Available It was proposed in the former research that chaos control can be used to suppress electromagnetic interference (EMI in DC–DC converters. Analysis on a half-bridge converter is detailed in this study. Here, the practical example of the power supply of personal computers is given to show that, with an external chaotic signal to a pulse width modulation control circuit, the proposed approach can reduce EMI by reducing the amplitudes of power signals such as transformer current and output inductor currents at multiples of fundamental frequency.

  18. Threat of Electromagnetic Pulse Bomb and Its Radar Countermeasure%电磁脉冲炸弹的威胁及雷达防护研究

    Institute of Scientific and Technical Information of China (English)

    韩阳阳; 苏五星; 李建东

    2014-01-01

    Electromagnetic pulse bomb is already being used in the actual war. It is a real threat to radar. Firstly, the strong electromagnetic pulse interference waveforms and two kinds of func-tion methods are analyzed, power density changes of electromagnetic pulse is simulated and ana-lyzed;then, combined with its action mechanism, calculation analysis is carried on from three aspects ( the radar antenna, cable and application) . Finally, strong electromagnetic pulse jam-ming protection method is analyzed; a strong electromagnetic jamming protection technology based on electromagnetic bionics is put forward.%电磁脉冲炸弹已经实战应用,对雷达有着现实威胁。首先分析了强电磁脉冲干扰的波形以及两种作用方式,并仿真分析了电磁脉冲功率密度的变化;然后结合其作用机理,从雷达的天线,方舱和线缆三方面对其威胁进行计算分析;最后分析了强电磁脉冲干扰的防护方法,提出了基于电磁仿生技术的雷达强电磁脉冲干扰防护思想。

  19. Electromagnetic characterization of fractured rock for geological disposal studies of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Eloranta, E. [Radiation and Nuclear Safety Authority, Helsinki (Finland); Ermutlu, M. [Nokia Research Center, Helsinki (Finland); Flykt, M.; Lindell, I.; Nikoskinen, K.; Sihvola, A. [Helsinki Univ. of Technology, Espoo (Finland). Electromagnetics Lab.

    1998-04-01

    In the report, the results of a joint research project carried out in 1991-1997 by the Finnish Radiation and Nuclear Safety Authority (STUK) and the Electromagnetics Laboratory of the Helsinki University of Technology are presented. The main purpose was to create computational models for electric potential responses when the medium is anisotropic and is bounded by a perfect magnetic conductor, a perfect electric conductor, and an anisotropic impedance surface. Furthermore, the geometry of two anisotropic half spaces and a layered medium were considered. The solutions of the problems were made using image theory. For modeling the electric potential in anisotropic medium with inhomogeneities, an integral equation was formulated. Also a wedge structure was treated as an extension to the traditional two parallel plate model of fracture geometry. The equivalentization of fracturing with anisotropy is a research area that still continues that still continues 46 refs. The publication contains also fourteen previous publications by authors

  20. Two-pulse laser control of nuclear and electronic motion

    DEFF Research Database (Denmark)

    Grønager, Michael; Henriksen, Niels Engholm

    1997-01-01

    We discuss an explicitly time-dependent two-pulse laser scheme for controlling where nuclei and electrons are going in unimolecular reactions. We focus on electronic motion and show, with HD+ as an example, that one can find non-stationary states where the electron (with some probability) oscilla...

  1. Investigation into the electromagnetic impulses from long-pulse laser illuminating solid targets inside a laser facility

    Science.gov (United States)

    Yi, Tao; Yang, Jinwen; Yang, Ming; Wang, Chuanke; Yang, Weiming; Li, Tingshuai; Liu, Shenye; Jiang, Shaoen; Ding, Yongkun; Xiao, Shaoqiu

    2016-09-01

    Emission of the electromagnetic pulses (EMP) due to laser-target interaction in laser facility had been evaluated using a cone antenna in this work. The microwave in frequencies ranging from several hundreds of MHz to 2 GHz was recorded when long-pulse lasers with several thousands of joules illuminated the solid targets, meanwhile the voltage signals from 1 V to 4 V were captured as functions of laser energy and backlight laser, where the corresponding electric field strengths were obtained by simulating the cone antenna in combination with conducting a mathematical process (Tiknohov Regularization with L curve). All the typical coupled voltage oscillations displayed multiple peaks and had duration of up to 80 ns before decaying into noise and mechanisms of the EMP generation was schematically interpreted in basis of the practical measuring environments. The resultant data were expected to offer basic know-how to achieve inertial confinement fusion.

  2. Electromagnetically induced transparency and nonlinear pulse propagation in a combined tripod and Λ atom-light coupling scheme

    Science.gov (United States)

    Hamedi, H. R.; Ruseckas, J.; Juzeliūnas, G.

    2017-09-01

    We consider propagation of a probe pulse in an atomic medium characterized by a combined tripod and Lambda (Λ) atom-light coupling scheme. The scheme involves three atomic ground states coupled to two excited states by five light fields. It is demonstrated that dark states can be formed for such an atom-light coupling. This is essential for formation of the electromagnetically induced transparency (EIT) and slow light. In the limiting cases the scheme reduces to conventional Λ- or N-type atom-light couplings providing the EIT or absorption, respectively. Thus, the atomic system can experience a transition from the EIT to the absorption by changing the amplitudes or phases of control lasers. Subsequently the scheme is employed to analyze the nonlinear pulse propagation using the coupled Maxwell-Bloch equations. It is shown that a generation of stable slow light optical solitons is possible in such a five-level combined tripod and Λ atomic system.

  3. Transition-Selective Pulses in Zero-Field Nuclear Magnetic Resonance.

    Science.gov (United States)

    Sjolander, Tobias F; Tayler, Michael C D; King, Jonathan P; Budker, Dmitry; Pines, Alexander

    2016-06-30

    We use low-amplitude, ultralow frequency pulses to drive nuclear spin transitions in zero and ultralow magnetic fields. In analogy to high-field NMR, a range of sophisticated experiments becomes available as these allow narrow-band excitation. As a first demonstration, pulses with excitation bandwidths 0.5-5 Hz are used for population redistribution, selective excitation, and coherence filtration. These methods are helpful when interpreting zero- and ultralow-field NMR spectra that contain a large number of transitions.

  4. Pulsed Photofission Delayed Gamma Ray Detection for Nuclear Material Identification

    Energy Technology Data Exchange (ETDEWEB)

    John Kavouras; Xianfei Wen; Daren R. Norman; Dante R. Nakazawa; Haori Yang

    2012-11-01

    Innovative systems with increased sensitivity and resolution are in great demand to detect diversion and to prevent misuse in support of nuclear materials management for the U.S. fuel cycle. Nuclear fission is the most important multiplicative process involved in non-destructive active interrogation. This process produces the most easily recognizable signature for nuclear materials. High-energy gamma rays can also excite a nucleus and cause fission through a process known as photofission. After photofission reactions, delayed signals are easily distinguishable from the interrogating radiation. Linac-based, advanced inspection techniques utilizing the fission signals after photofission have been extensively studied for homeland security applications. Previous research also showed that a unique delayed gamma ray energy spectrum exists for each fissionable isotope. Isotopic composition measurement methods based on delayed gamma ray spectroscopy will be the primary focus of this work.

  5. Nuclear forward scattering of synchrotron radiation in pulsed high magnetic fields.

    Science.gov (United States)

    Strohm, C; Van der Linden, P; Rüffer, R

    2010-02-26

    We report the demonstration of nuclear forward scattering of synchrotron radiation from 57Fe in ferromagnetic alpha iron in pulsed high magnetic fields up to 30 T. The observed magnetic hyperfine field follows the calculated high field bulk magnetization within 1%, establishing the technique as a precise tool for the study of magnetic solids in very high magnetic fields. To perform these experiments in pulsed fields, we have developed a detection scheme for fully time resolved nuclear forward scattering applicable to other pump probe experiments.

  6. Electron - nuclear recoil discrimination by pulse shape analysis

    CERN Document Server

    Elbs, J; Collin, E; Godfrin, H; Suvorova, O

    2007-01-01

    In the framework of the ``ULTIMA'' project, we use ultra cold superfluid 3He bolometers for the direct detection of single particle events, aimed for a future use as a dark matter detector. One parameter of the pulse shape observed after such an event is the thermalization time constant. Until now it was believed that this parameter only depends on geometrical factors and superfluid 3He properties, and that it is independent of the nature of the incident particles. In this report we show new results which demonstrate that a difference for muon- and neutron events, as well as events simulated by heater pulses exist. The possibility to use this difference for event discrimination in a future dark matter detector will be discussed.

  7. Nuclear reactor pulse calibration using a CdZnTe electro-optic radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Kyle A., E-mail: knelson1@ksu.edu [S.M.A.R.T. Laboratory, Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS 66506 (United States); Geuther, Jeffrey A. [TRIGA Mark II Nuclear Reactor, Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS 66506 (United States); Neihart, James L.; Riedel, Todd A. [S.M.A.R.T. Laboratory, Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS 66506 (United States); Rojeski, Ronald A. [Nanometrics, Inc., 1550 Buckeye Drive, Milpitas, CA 95035 (United States); Saddler, Jeffrey L. [TRIGA Mark II Nuclear Reactor, Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS 66506 (United States); Schmidt, Aaron J.; McGregor, Douglas S. [S.M.A.R.T. Laboratory, Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS 66506 (United States)

    2012-07-15

    A CdZnTe electro-optic radiation detector was used to calibrate nuclear reactor pulses. The standard configuration of the Pockels cell has collimated light passing through an optically transparent CdZnTe crystal located between crossed polarizers. The transmitted light was focused onto an IR sensitive photodiode. Calibrations of reactor pulses were performed using the CdZnTe Pockels cell by measuring the change in the photodiode current, repeated 10 times for each set of reactor pulses, set between 1.00 and 2.50 dollars in 0.50 increments of reactivity. - Highlights: Black-Right-Pointing-Pointer We demonstrated the first use of an electro-optic device to trace reactor pulses in real-time. Black-Right-Pointing-Pointer We examined the changes in photodiode current for different reactivity insertions. Black-Right-Pointing-Pointer Created a linear best fit line from the data set to predict peak pulse powers.

  8. Incident, Action, Recovery, and Recommissioning for the 4.5-MJ Pulsed Power Supply Located at the Electromagnetic Gun Facility, Barricade C, Aberdeen Proving Ground, MD

    Science.gov (United States)

    2007-04-01

    modified and, in 2001, was placed back in operation at barricade C to operate with an electromagnetic (EM) railgun load. On 9 February 2006, a capacitor ...MJ. 15. SUBJECT TERMS pulsed power, capacitor , railgun , armature, incident 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON...back in operation at barricade C to operate with an electromagnetic railgun load. The PPS consists of 18 250-kJ independently triggered modules

  9. Instrumental correction of counting losses in nuclear pulse spectroscopy

    Science.gov (United States)

    Westphal, G. P.

    1985-05-01

    The virtual pulse generator (VPG) method of counting loss correction [1-3] is the first truly quantitative instrumental correction procedure taking into account both dead-time and pileup losses of a spectroscopy system over its full operative range of counting rates without the need for fast signal detection channels [4-6] or ambiguous post-processing of data [7,8], or the necessity to process artificial test pulses in addition to the detector signals [9]. Consequently, the VPG method is not limited in test frequency thus enabling the on-line generation of loss correction factors of sufficient statistical accuracy within extremely short periods of time. By adding weighting factors to the channels addressed by the analog-to-digital converter during the course of the measurement (instead of one as in conventional pulse height analysis) real-time correction of counting losses is made possible with millisecond time of response. Increased statistical accuracy may be achieved when using the VPG principle for loss-dependent prolonging of the measuring time similar to the live-time clock method. Both real-time and live-time modes of operation are provided for in a commercially available VPG correction module [10]. After a description of the set-up procedure of the module in connection with a likewise commercial semi-Gaussian shaping amplifier the performance of the VPG correction is exemplified to a level of 0.2% with the aid of repetitive two-source measurements in both the real-time and the live-time mode of operation.

  10. Giant pulses of the Crab Nebula pulsar as an indicator of a strong electromagnetic wave

    Science.gov (United States)

    Popov, M. V.; Rudnitskii, A. G.; Soglasnov, V. A.

    2017-03-01

    The spectra and visibility functions of giant pulses of the Crab Nebula pulsar derived from VLBI observations carried out through the "RadioAstron" project in 2015 are analyzed. Parameters of the scattering of the pulses in the interstellar medium are measured, namely, the scattering time and decorrelation bandwidth. A comparative analysis of the shapes of the spectra and visibility functions of giant pulses obtained in real observations and via modeling of their scattering is carried out. The results suggest the presence of short bursts ( dt leading to the generation of additional radiation perpendicular to the direction of propagation of the giant pulses. This radiation may be associated with anomalous components of the mean pulse profile observed at frequencies above 4 GHz.

  11. Noise signals and carrier modulation arising in electrical cables during nuclear pulse irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Both, E.; Bruemmer, H. P.; Lascaro, C. P.; Newberg, J.; Schlosser, W.

    1963-03-15

    Electrical noise signals generated in coaxial and other cables by pulsed nuclear radiation were measured as a function of applied voltage and exposure history. In consecutive exposures the signal magnitude and polarity was found to be strongly affected by training and memory effects. Unexpectedly large signals in the cable shield were identified as the cause for oscillatory signals in the center conductor and for the occurrence of parasitic leakage currents in nearby conductors. A r-f signal transmitted through RG62 A/U cable undergoes a temporary attenuation during the radiation pulse while it passes through RG59 B/U without measurable degradation. Definite rules are given for minimizing cable noise signals in nuclear pulse radiation measurements. (auth)

  12. 76 FR 37798 - DOE Response to Recommendation 2010-2 of the Defense Nuclear Facilities Safety Board, Pulse Jet...

    Science.gov (United States)

    2011-06-28

    ... Response to Recommendation 2010-2 of the Defense Nuclear Facilities Safety Board, Pulse Jet Mixing at the..., concerning Pulse Jet Mixing at the Waste Treatment and Immobilization Plant, to the Department of Energy. In... Safety Board (Board) Recommendation 2010-2, Pulse Jet Mixing (PJM) at the Waste Treatment...

  13. Trigger-less readout system with pulse pile-up recovery for the PANDA electromagnetic calorimeter

    NARCIS (Netherlands)

    Kavatsyuk, M.; Tambave, G.; Hevinga, M.; Lemmens, P. J. J.; Schakel, P.; Schreuder, F.; Speelman, R.; Löhner, H.

    2013-01-01

    A simple, efficient, and robust on-line data-processing scheme was developed for the digital front-end electronics of the electromagnetic calorimeter of the PANDA spectrometer at FAIR, Darmstadt. The implementation of the processing algorithm in FPGA enables the construction of an almost dead-time f

  14. The application of frequency swept pulses for the acquisition of nuclear quadrupole resonance spectra

    Science.gov (United States)

    Rossini, Aaron J.; Hamaed, Hiyam; Schurko, Robert W.

    2010-09-01

    The acquisition of nuclear quadrupole resonance (NQR) spectra with wideband uniform rate and smooth truncation (WURST) pulses is investigated. 75As and 35Cl NQR spectra acquired with the WURST echo sequence are compared to those acquired with standard Hahn-echo sequences and echo sequences which employ composite refocusing pulses. The utility of WURST pulses for locating NQR resonances of unknown frequency is investigated by monitoring the integrated intensity and signal to noise of 35Cl and 75As NQR spectra acquired with transmitter offsets of several hundreds kilohertz from the resonance frequencies. The WURST echo sequence is demonstrated to possess superior excitation bandwidths in comparison to the pulse sequences which employ conventional monochromatic rectangular pulses. The superior excitation bandwidths of the WURST pulses allows for differences in the characteristic impedance of the receiving and excitation circuits of the spectrometer to be detected. Impedance mismatches have previously been reported by Marion and Desvaux [D.J.Y. Marion, H. Desvaux, J. Magn. Reson. (2008) 193(1) 153-157] and Muller et al. [M. Nausner, J. Schlagnitweit, V. Smrecki, X. Yang, A. Jerschow, N. Muller, J. Magn. Reson. (2009) 198(1) 73-79]. In this regard, WURST pulse sequences may afford an efficient new method for experimentally detecting impedance mismatches between receiving and excitation circuits, allowing for the optimization of solids and solution NMR and NQR spectrometer systems. The use of the Carr-Purcell Meiboom-Gill (CPMG) pulse sequence for signal enhancement of NQR spectra acquired with WURST pulses and conventional pulses is also investigated. Finally, the utility of WURST pulses for the acquisition of wideline NQR spectra is demonstrated by acquiring part of the 63/65Cu NQR spectrum of CuCN.

  15. Quantum Computing Using Pulse-Based Electron-Nuclear Double Resonance (endor):. Molecular Spin-Qubits

    Science.gov (United States)

    Sato, Kazuo; Nakazawa, Shigeki; Rahimi, Robabeh D.; Nishida, Shinsuke; Ise, Tomoaki; Shimoi, Daisuke; Toyota, Kazuo; Morita, Yasushi; Kitagawa, Masahiro; Carl, Parick; Höfner, Peter; Takui, Takeji

    2009-06-01

    Electrons with the spin quantum number 1/2, as physical qubits, have naturally been anticipated for implementing quantum computing and information processing (QC/QIP). Recently, electron spin-qubit systems in organic molecular frames have emerged as a hybrid spin-qubit system along with a nuclear spin-1/2 qubit. Among promising candidates for QC/QIP from the materials science side, the reasons for why electron spin-qubits such as molecular spin systems, i.e., unpaired electron spins in molecular frames, have potentialities for serving for QC/QIP will be given in the lecture (Chapter), emphasizing what their advantages or disadvantages are entertained and what technical and intrinsic issues should be dealt with for the implementation of molecular-spin quantum computers in terms of currently available spin manipulation technology such as pulse-based electron-nuclear double resonance (pulsed or pulse ENDOR) devoted to QC/QIP. Firstly, a general introduction and introductory remarks to pulsed ENDOR spectroscopy as electron-nuclear spin manipulation technology is given. Super dense coding (SDC) experiments by the use of pulsed ENDOR are also introduced to understand differentiating QC ENDOR from QC NMR based on modern nuclear spin technology. Direct observation of the spinor inherent in an electron spin, detected for the first time, will be shown in connection with the entanglement of an electron-nuclear hybrid system. Novel microwave spin manipulation technology enabling us to deal with genuine electron-electron spin-qubit systems in the molecular frame will be introduced, illustrating, from the synthetic strategy of matter spin-qubits, a key-role of the molecular design of g-tensor/hyperfine-(A-)tensor molecular engineering for QC/QIP. Finally, important technological achievements of recently-emerging CD ELDOR (Coherent-Dual ELectron-electron DOuble Resonance) spin technology enabling us to manipulate electron spin-qubits are described.

  16. Laser pulse heating of nuclear fuels for simulation of reactor power transients

    Indian Academy of Sciences (India)

    C S Viswanadham; K C Sahoo; T R G Kutty; K B Khan; V P Jathar; S Anantharaman; Arun Kumar; G K Dey

    2010-12-01

    It is important to study the behaviour of nuclear fuels under transient heating conditions from the point of view of nuclear safety. To simulate the transient heating conditions occurring in the known reactor accidents like loss of coolant accident (LOCA) and reactivity initiated accident (RIA), a laser pulse heating system is under development at BARC, Mumbai. As a prelude to work on irradiated nuclear fuel specimens, pilot studies on unirradiated UO2 fuel specimens were carried out. A laser pulse was used to heat specimens of UO2 held inside a chamber with an optically transparent glass window. Later, these specimens were analysed by metallography and X-ray diffraction. This paper describes the results of these studies.

  17. Device for measurement of power and shape of radio frequency pulses in nuclear magnetic resonance

    Science.gov (United States)

    Pfeffer, M.; Řezníček, R.; Křišťan, P.; Štěpánková, H.

    2012-05-01

    A design of an instrument to measure the power and shape of radio frequency (RF) pulses operating in a broad frequency range is described. The device is capable of measuring the pulse power up to 500 W of both CW and extremely short (˜1 μs) RF pulses of arbitrary period. The pulse envelope can be observed on a logarithmic scale on a corresponding instrument output using an inexpensive storage oscilloscope. The instrument consists of a coaxial measurement head, the RF processing circuits and an AD conversion and display unit. The whole device is based on widely available integrated circuits; thus, good reproducibility and adaptability of the design is ensured. Since the construction is intended to be used in particular (but not solely) in nuclear magnetic resonance spectroscopy, we found it useful to provide a demonstration of two typical usage scenarios. Other application fields may comprise magnetic resonance imaging, radar and laser technology, power amplifier testing, etc.

  18. A novel acquisition method of nuclear spectrum based on pulse area analysis

    CERN Document Server

    Dongcang, Li; Lei, Yang; Zhong, Qi; Xiangting, Meng; Bitao, Hu

    2014-01-01

    A novel method based on pulse area analysis(PAA) was presented for acquisition nuclear spectrum by the digitizer. PAA method can be used as a substitute for the traditional method of pulse height analysis (PHA). In the PAA method a commercial digitizer was employed to sample and sum in the pulse, and the area of pulse is proportional to the energy of the detected radiation. The results of simulation and experiment indicate the great advantages of PAA method, especially when the count rate is high and shaping time constant is small. When shaping time constant is 0.5us, the energy resolution of PAA is about 66% better than that of PHA.

  19. Laser diode stacks:pulsed light power for nuclear fusion

    Institute of Scientific and Technical Information of China (English)

    Martin Wlz; Agnieszka Pietrzak; Alex Kindsvater; Jens Meusel; Klaus Stolberg; Ralf Hlsewede; Jrgen Sebastian; Valentin Loyo-Maldonado

    2016-01-01

    Laser drivers are an enabling factor to inertial confinement fusion, because laser diodes must be used instead of flash lamps. We discuss the limitations of laser diode arrays and show what steps the industry is taking. The pump power requirements of large-scale projects such as LIFE or Hi PER are within reach of semiconductor laser diode assemblies.Pulsed light output powers per laser bars have been around 300 W per bar, as in the Jenoptik 940 nm bars previously used for pumping the Yb:YAG slabs in the Di POLE project. By redesigning the semiconductor laser structures 500 W per bar is now commercially available for 808, 880 and 940 nm pump wavelengths. The construction of one inertial fusion power plant will require an amount of semiconductor laser chips in excess of the current annual production by two orders of magnitude. This adds to the engineering task of improving the device characteristics a challenge to production capacity.While the industry benefits from the recent boost in solid-state lighting that acts as a technology driver, cooperation between manufacturers will be imperative, and to this end we propose standardization efforts.

  20. Empirical compensation function for eddy current effects in pulsed field gradient nuclear magnetic resonance experiments.

    Science.gov (United States)

    Zhu, X X; Macdonald, P M

    1995-05-01

    An empirical compensation function for the correction of eddy current effects in the Stejskal-Tanner pulsed-gradient spin-echo (PGSE) nuclear magnetic resonance (NMR) experiments has been established. Eddy currents may arise as a result of the application of sharp and strong gradient pulses and may cause severe distortion of the NMR signals. In this method, the length of one gradient pulse is altered to compensate for the eddy current effects. The compensation is considered to be ideal when the position and the phase of the spin-echo maximum obtained from an aqueous solution of poly(ethylene glycol) (PEG) is the same in the presence and absence of a gradient pulse in the PGSE pulse sequence. We first characterized the functional dependence of the length of the required compensation on the three principal variables in the PGSE experiment: the gradient strength, the duration of the gradient pulse, and the interval between the two gradient pulses. Subsequently, we derived a model which successfully describes the general relationship between these variables and the size of the induced eddy current. The parameters extracted from fitting the model to the experimental compensation data may be used to predict the correct compensation for any combination of the three principal variables.

  1. BLANKET REPRESENTATION AND EXPEDIENT OF DISINFECTING WATER USING PULSING ELECTROMAGNETIC FIELD

    Directory of Open Access Journals (Sweden)

    Ibragimova Ozoda

    2013-11-01

    Full Text Available ABSTRACT:  The paper deals with comparative analysis of existing expedients and devices of disinfecting water, spots ways of the solution and a new method of  water purification using electromagnetic field applied in a cross wise direction. ABSTRAK: Dalam operasi, analisis perbandingan dijalankan bagi menentukan  kesesuaian yang sedia ada dan alatan untuk menyahjangkit air. Dengan mengaplikasikan medan magnet lintang, penyelesaian masalah dikenal pasti dengan meningkatkan kemagnetan terhadap medan elektromagnet ke atas air.

  2. Investigation of battery-charged-capacitor pulsed-power systems for electromagnetic-launcher experiments. Final report, Jan 90-Apr 91

    Energy Technology Data Exchange (ETDEWEB)

    Cornette, J.B.

    1992-02-01

    Candidate pulsed power systems for electromagnetic launchers constitute two broad categories: rotating machinery and non-rotating devices. Rotating machinery for this purpose is under development at several industrial and educational institutions around the world. Non-rotating hardware includes capacitors, batteries, and inductors. These, too, are the subject of research programs, but as yet, are much larger than rotating supplies of equal power and energy capability. In 1988, system studies identified several attractive pulsed power systems for electromagnetic launchers. Battery charged capacitor pulsed power systems were among those identified as promising for electromagnetic launcher systems. The basic equations governing the battery charging capacitor sequence, and the capacitor discharge into an electromagnetic launcher are the subject of this report. A battery charged capacitor system powering an electromagnetic launcher has also been built and tested. This experiment not only validates the system concept with presently available hardware, but can be used to establish a baseline for evaluation of future systems when technology in capacitor and battery power and energy densities improve.

  3. Influence of the external component on the damage of the bipolar transistor induced by the electromagnetic pulse

    Science.gov (United States)

    Xiaowen, Xi; Changchun, Chai; Xingrong, Ren; Yintang, Yang; Zhenyang, Ma; Jing, Wang

    2010-07-01

    A study on the influence of the external resistor and the external voltage source during the injection of the electromagnetic pulse (EMP) into the bipolar transistor (BJT) is carried out. Research shows that the increase of the external resistor Rb at base makes the burnout time of the device decrease slightly, the increase of the external voltage source Vbe at base can aid the damage of the device when the magnitude of the injecting voltage is relatively low and has little influence when the magnitude is sufficiently high causing the device appearing the PIN structure damage, and the increase of the external resistor Re can remarkably reduce the voltage drops added to the device and improve the durability of the device. In the final analysis, the effect of the external circuit component on the BJT damage is the influence on the condition which makes the device appear current-mode second breakdown.

  4. Influence of the external component on the damage of the bipolar transistor induced by the electromagnetic pulse

    Energy Technology Data Exchange (ETDEWEB)

    Xi Xiaowen; Chai Changchun; Ren Xingrong; Yang Yintang; Ma Zhenyang; Wang Jing, E-mail: xixiaowen523103@163.co [Key Laboratory of Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi' an 710071 (China)

    2010-07-15

    A study on the influence of the external resistor and the external voltage source during the injection of the electromagnetic pulse (EMP) into the bipolar transistor (BJT) is carried out. Research shows that the increase of the external resistor R{sub b} at base makes the burnout time of the device decrease slightly, the increase of the external voltage source V{sub be} at base can aid the damage of the device when the magnitude of the injecting voltage is relatively low and has little influence when the magnitude is sufficiently high causing the device appearing the PIN structure damage, and the increase of the external resistor R{sub e} can remarkably reduce the voltage drops added to the device and improve the durability of the device. In the final analysis, the effect of the external circuit component on the BJT damage is the influence on the condition which makes the device appear current-mode second breakdown.

  5. Electromagnetic protection assessment of naval vessels

    NARCIS (Netherlands)

    Middelkoop, R.; Vernooy, J.A.M.

    1993-01-01

    Modern naval vessels are well equipped with a lot of weapon and sensor systems, all controlled by electronics. Mutual interference between all those electronic systems as well as illumination of a ship by an Electromagnetic Pulse (EMP) caused by lightning or by a nuclear detonation can potentially u

  6. Spectral and dynamic properties of stimulated electromagnetic emission (SEE) generated by very short diagnostic pulses

    Science.gov (United States)

    Sergeev, Evgeny; Grach, Savely

    Results of the experimental investigations of the HF Upper Hybrid and LF ionospheric tur-bulence by the SEE diagnostic technique over the SURA heating facility are presented. For pumping of the ionosphere an alternation of two basic time modes was used: (1) high duty cycles, i.e. long pulses with a short pauses of 20-30 ms between them, in addition short (diag-nostic) pump pulses with a duration τ ≤ 200 µs were radiated in the middle of the pauses; (2) low-duty cycles consisting of short pulses τ ≤ 200 µs and interpulse period T = 20-200 ms. It is known that the SEE spectral shape and dynamics are determined mainly by the pump-induced UH plasma waves, while the LF turbulence (striations) is responsible for SEE intensity and interpulse dynamics. In previous experiments longer diagnostic pulses (τ 10-30 ms) and interpulse periods (T = 1-3 s) were used. The reduction of τ and T diminishes an influence of the pulses upon tested processes and improves a temporal resolution of the diagnostic SEE measurements. In case of well developed striations (during high duty cycle) diagnostic pulses excite the upper hybrid plasma waves, and, therefore, the SEE with frequencies close to diag-nostic pulse frequency fd practically without time delay. So far as the pulse duration τ was chosen to be much less than a period of their multiple ionospheric reflections (˜ 2 ms) we were able to analyze the decaying SEE spectra just after the ionospherically reflected pulse trailing edge during periods between multiple signal hops in a whole frequency bandwidth including the fd close vicinity. Observations have shown that the SEE spectral maximum is shifted towards lower frequencies from fd by 2-4 kHz during high duty cycle (well-developed striations), and by up to 4-6 kHz after the mode switching to low duty cycle. Then the SEE intensity decreases from pulse to pulse together with striation relaxation. The typical e-folding decay time of the total SEE intensity after the diagnostic

  7. Understanding the ATLAS electromagnetic barrel pulse shapes and the absolute electronic calibration

    CERN Document Server

    Neukermans, L; Zitoun, R

    2001-01-01

    We present an original method to undestand the calibration and physics pulse shapes collected in the 2000 barrel test beam runs with the prototype module. It is based on an electrical description of the calorimeter and its electronics. It allows an understanding of the physics pulse shapes and its absolute calibration (in microA/ADC) to a very good level of accuracy with a small number of parameters (capacitances and inductances). The electrical parameters found by this method agree with the direct measurements independantly performed on the prototype module. Optimal filtering coefficients can then be derived from these physics pulse shape predictions, and more crucial, an absolute electronic calibration. These coefficients are released in the official test beam software EMTB.

  8. Research of manufacturing high voltage nanosecond electromagnetic pulse attenuator%高压纳秒电磁脉冲衰减器的研制

    Institute of Scientific and Technical Information of China (English)

    陈炜峰; 宋珂锦

    2012-01-01

    随着电磁脉冲技术的发展,电磁脉冲前沿越来越快,峰值越来越高.针对这些特点,为了减小高压纳秒电磁脉冲传输、衰减过程中电磁波的反射,在输出端得到理想的电磁脉冲波形,设计了一种高压纳秒电磁脉冲衰减器,采用高频电磁场仿真软件HFSS建模仿真,分析驻波比,优化结构尺寸.根据仿真及优化结果,制作了衰减量为30%和40%的衰减器样机.实验表明样机衰减量误差小,传输性能好,可对上升时间2 ns左右,峰值小于40 kV的电磁脉冲实现有效衰减.%With the development of technology of electromagnetic pulse, the rising of electromagnetic pulse is more and more quickly, the peak is higher and higher. According to these characteristics, in order to reduce the reflex of high voltage nanosecond electromagnetic pulse in transmission and attenuation which can output the ideal electromagnetic pulse waveform, design of a high voltage nanosecond electromagnetic pulse attenuator, using high-frequency electromagnetic simulation software HFSS modeling,the size of the structure was optimized base on simulation,and got the simulation of VSWR (voltage standing wave ratio). According to the simulation and structural optimization of results,making attenuation for 30% and 40% of the attenuator prototype. Experimental validation of a prototype performance good, .deviation small,the attenuator had effective attenuation on the electromagnetic pulse which riseing time is about 2 ns,peak of pulse is less than 40 kV.

  9. Tailoring single-cycle electromagnetic pulses in the 2-9 THz frequency range using DAST/SiO2 multilayer structures pumped at Ti:sapphire wavelength

    CERN Document Server

    Stepanov, Andrei G; Bonacina, Luigi; Wolf, Jean-Pierre; Hauri, Christoph P

    2014-01-01

    We present a numerical parametric study of single-cycle electromagnetic pulse generation in a DAST/SiO2 multilayer structure via collinear optical rectification of 800 nm femtosecond laser pulses. It is shown that modifications of the thicknesses of the DAST and SiO2 layers allow tuning of the average frequency of the generated THz pulses in the frequency range from 3 to 6 THz. The laser-to-THz energy conversion efficiency in the proposed structures is compared with that in a bulk DAST crystal and a quasi-phase-matching periodically poled DAST crystal and shows significant enhancement.

  10. A Fast Pulsed Neutron Source for Time-of-Flight Detection of Nuclear Materials and Explosives

    Science.gov (United States)

    Krishnan, Mahadevan; Bures, Brian; James, Colt; Madden, Robert; Hennig, Wolfgang; Breus, Dimitry; Asztalos, Stephen; Sabourov, Konstantin; Lane, Stephen

    2011-12-01

    AASC has built a fast pulsed neutron source based on the Dense Plasma Focus (DPF). The more current version stores only 100 J but fires at ˜10-50 Hz and emits ˜106n/pulse at a peak current of 100 kA. Both sources emit 2.45±0.1 MeV (DD) neutron pulses of ˜25-40 ns width. Such fast, quasi-monoenergetic pulses allow time-of-flight detection of characteristic emissions from nuclear materials or high explosives. A test is described in which iron targets were placed at different distances from the point neutron source. Detectors such as Stilbene and LaBr3 were used to capture inelastically induced, 847 keV gammas from the iron target. Shielding of the source and detectors eliminated most (but not all) of the source neutrons from the detectors. Gated detection, pulse shape analysis and time-of-flight discrimination enable separation of gamma and neutron signatures and localization of the target. A Monte Carlo simulation allows evaluation of the potential of such a fast pulsed source for a field-portable detection system. The high rep-rate source occupies two 200 liter drums and uses a cooled DPF Head that is <500 cm3 in volume.

  11. A Fast Pulsed Neutron Source for Time-of-Flight Detection of Nuclear Materials and Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, Mahadevan; Bures, Brian; James, Colt; Madden, Robert [Alameda Applied Sciences Corporation, 3077 Teagarden Street, San Leandro, CA 94577 (United States); Hennig, Wolfgang; Breus, Dimitry; Asztalos, Stephen; Sabourov, Konstantin [XIA LLC, 31057 Genstar Road, Hayward, CA 94544 (United States); Lane, Stephen [NSF Center for Biophotonics and School of Medicine, University of California Davis, Sacramento CA, 95817 (United States)

    2011-12-13

    AASC has built a fast pulsed neutron source based on the Dense Plasma Focus (DPF). The more current version stores only 100 J but fires at {approx}10-50 Hz and emits {approx}10{sup 6}n/pulse at a peak current of 100 kA. Both sources emit 2.45{+-}0.1 MeV(DD) neutron pulses of {approx}25-40 ns width. Such fast, quasi-monoenergetic pulses allow time-of-flight detection of characteristic emissions from nuclear materials or high explosives. A test is described in which iron targets were placed at different distances from the point neutron source. Detectors such as Stilbene and LaBr3 were used to capture inelastically induced, 847 keV gammas from the iron target. Shielding of the source and detectors eliminated most (but not all) of the source neutrons from the detectors. Gated detection, pulse shape analysis and time-of-flight discrimination enable separation of gamma and neutron signatures and localization of the target. A Monte Carlo simulation allows evaluation of the potential of such a fast pulsed source for a field-portable detection system. The high rep-rate source occupies two 200 liter drums and uses a cooled DPF Head that is <500 cm{sup 3} in volume.

  12. Pulsed spectrometer for nuclear quadrupole resonance for remote detection of nitrogen in explosives

    Science.gov (United States)

    Anferov, V. P.; Mozjoukhine, G. V.; Fisher, R.

    2000-04-01

    We describe a pulsed spectrometer for detection of nuclear quadrupole resonance on the nuclei of nitrogen N-14 with fast Fourier transform. The use of a multipulse sequence, four channel system for data registration and processing permits detection of the nuclear quadrupole resonance (NQR) signal in the presence of strong interference and the piezo effect. Using this spectrometer we registered the NQR signal from an explosive sample of 150 g (92% RDX) at a distance of 22 cm, and the time of detection was 81 s.

  13. Transient interaction model of electromagnetic field generated by lightning current pulses and human body

    Science.gov (United States)

    Iváncsy, T.; Kiss, I.; Szücs, L.; Tamus, Z. Á.

    2015-10-01

    The lightning current generates time-varying magnetic field near the down- conductor and the down-conductors are mounted on the wall of the buildings where residential places might be situated. It is well known that the rapidly changing magnetic fields can generate dangerous eddy currents in the human body.The higher duration and gradient of the magnetic field can cause potentially life threatening cardiac stimulation. The coupling mechanism between the electromagnetic field and the human body is based on a well-known physical phenomena (e.g. Faradays law of induction). However, the calculation of the induced current is very complicated because the shape of the organs is complex and the determination of the material properties of living tissues is difficult, as well. Our previous study revealed that the cardiac stimulation is independent of the rising time of the lightning current and only the peak of the current counts. In this study, the authors introduce an improved model of the interaction of electromagnetic fields of lighting current near down-conductor and human body. Our previous models are based on the quasi stationer field calculations, the new improved model is a transient model. This is because the magnetic field around the down-conductor and in the human body can be determined more precisely, therefore the dangerous currents in the body can be estimated.

  14. Nuclear reactor pulse tracing using a CdZnTe electro-optic radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Kyle A., E-mail: nuclearengg@gmail.com [S.M.A.R.T. Laboratory, Mechanical and Nuclear Engineering, Kansas State University, Manhattan KS 66506 (United States); Geuther, Jeffrey A. [TRIGA Mark II Nuclear Reactor, Mechanical and Nuclear Engineering, Kansas State University, Manhattan KS 66506 (United States); Neihart, James L.; Riedel, Todd A. [S.M.A.R.T. Laboratory, Mechanical and Nuclear Engineering, Kansas State University, Manhattan KS 66506 (United States); Rojeski, Ronald A. [Nanometrics, Inc., 1550 Buckeye Drive, Milpitas CA 95035 (United States); Ugorowski, Philip B.; McGregor, Douglas S. [S.M.A.R.T. Laboratory, Mechanical and Nuclear Engineering, Kansas State University, Manhattan KS 66506 (United States)

    2012-07-11

    CdZnTe has previously been shown to operate as an electro-optic radiation detector by utilizing the Pockels effect to measure steady-state nuclear reactor power levels. In the present work, the detector response to reactor power excursion experiments was investigated. Peak power levels during an excursion were predicted to be between 965 MW and 1009 MW using the Fuchs-Nordheim and Fuchs-Hansen models and confirmed with experimental data from the Kansas State University TRIGA Mark II nuclear reactor. The experimental arrangement of the Pockels cell detector includes collimated laser light passing through a transparent birefringent crystal, located between crossed polarizers, and focused upon a photodiode. The birefringent crystal, CdZnTe in this case, is placed in a neutron beam emanating from a nuclear reactor beam port. After obtaining the voltage-dependent Pockels characteristic response curve with a photodiode, neutron measurements were conducted from reactor pulses with the Pockels cell set at the 1/4 and 3/4 wave bias voltages. The detector responses to nuclear reactor pulses were recorded in real-time using data logging electronics, each showing a sharp increase in photodiode current for the 1/4 wave bias, and a sharp decrease in photodiode current for the 3/4 wave bias. The polarizers were readjusted to equal angles in which the maximum light transmission occurred at 0 V bias, thereby, inverting the detector response to reactor pulses. A high sample rate oscilloscope was also used to more accurately measure the FWHM of the pulse from the electro-optic detector, 64 ms, and is compared to the experimentally obtained FWHM of 16.0 ms obtained with the {sup 10}B-lined counter.

  15. Glass transition temperatures of epoxy resins by pulsed nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Rutenberg, A.C.; Dorsey, G.F.; Peck, C.G.

    1976-04-21

    Pulsed nuclear magnetic resonance spectroscopy has been used to measure the glass transition temperatures of cured epoxy resins. These measurements make it possible to monitor the cure and determine the glass transition temperature as a function of the curing conditions and the concentration of the components. Knowledge of the glass transition temperature of the cured epoxies allows screening of them for a number of uses, including adhesives and coatings operations.

  16. Toxic Effects of Lead and Electromagnetic Pulse Energy on Memory Mechanisms

    Science.gov (United States)

    2012-08-01

    postsynaptic potentials ( EPSPs ). All data signals were digitized via a Digidata 1322A and recorded directly to computer hard disk using pCLAMP 9.0 software...varied to determine threshold values for EPSPs . Slices were stimulated with single test pulses every 30 s for at least 30 min to establish baseline... EPSPs . To induce LTP, theta-burst stimulation (TBS) was used that consisted of 3 trains applied at 30 s intervals, each train consisting of 3

  17. Electromagnetic fields from pulsed electron beam experiments in space - Spacelab-2 results

    Science.gov (United States)

    Bush, R. I.; Reeves, G. D.; Banks, P. M.; Neubert, T.; Williamson, P. R.

    1987-01-01

    During the Spacelab-2 mission a small satellite carrying various plasma diagnostic instruments was released from the Shuttle to coorbit at distances up to 300 m. During a magnetic conjunction of the Shuttle and the satellite an electron beam modulated at 1.22 kHz was emitted from the Shuttle during a 7 min period. The spatial structure of the electromagnetic fields generated by the beam was observed from the satellite out to a distance of 153 m perpendicular to the beam. The magnetic field amplitude of the strongest harmonics were comparable to the amplitude of simultaneously observed whistlers, while the electric field amplitudes were estimated to 1-10 mV/m.

  18. Health effects of electromagnetic field generated by lightning current pulses near down conductors

    Science.gov (United States)

    Tamus, Z. Á.; Novák, B.; Szücs, L.; Kiss, I.

    2011-06-01

    The lightning current generates a time varying magnetic field near down conductors, when lightning strikes the connected Franklin-rod. The down conductors are mounted on the wall of buildings, where residential places can be situated. It is well known that the rapidly changing magnetic fields could generate dangerous eddy currents in the human body. If the duration and the gradient of the magnetic field were high enough, the peripheral nerves are excited. In this study, the authors introduce an improved model of the interaction of electromagnetic fields of lighting current near a down conductor with the human body. The interaction model has two parts: estimation of the magnetic fields surrounding the down conductor and evaluation of health effects of rapid changing magnetic fields on the human body.

  19. Influence of pulse electromagnetic fields on electronic equipment and systems in smart buildings

    Directory of Open Access Journals (Sweden)

    Jacek Paś

    2016-07-01

    Full Text Available The article presents information about the impact of electromagnetic fields’ impulses on technical infrastructure of electronic equipment and systems in intelligent buildings. The use of modern technical solutions in intelligent building management, i.e., human resources control and automation systems, efficient building space management, requires a large number of integrated electronic systems. Impulse interference, lightning or electricity as natural phenomena are among the most responsible for the occurrence of interference in buses, transmission lines systems, electrical installations, equipment and electronic systems used in intelligent buildings. To a large extent, it is associated with catastrophic damages that may occur in electronic devices or in completed systems such as intelligent building, e.g. ICT, security, etc. under the influence of induced voltages and interfering signals’ currents. Keywords: noise, static electricity, lightning

  20. Calculation of Electromagnetic Force on End Face of Pulsed Reactor for Electromagnetic Launch%电磁发射用脉冲电抗器端面电磁力计算

    Institute of Scientific and Technical Information of China (English)

    俞小华; 董健年; 王浩; 刘佳

    2013-01-01

    为研究电磁发射武器中脉冲功率源内部电抗器端面的薄金属板所受电磁力,建立了电抗器磁场及金属板上感应涡流的简化模型,分析了脉冲放电时的电抗器磁场、矢量磁位、金属板上感应涡流以及电抗器与金属板之间的电磁力,得出解析计算式,并绘出涡流密度分布图及电磁力曲线.分析结果表明,感应电流分布与金属板大小有关,板边缘受电磁力影响较大,容易发生变形;受到激励电流和感应电流的共同影响,金属板所受电磁力在激励电流上升沿到达峰值,在感应电流为0时电磁力为0,之后衰减直至反向峰值.%To study electromagnetic force on a sheet metal located on the pulsed reactor end in the pulsed power supply module for electromagnetic launch,the simplified model was established based on the electromagnetic field features of pulsed reactor and the characteristics of the eddy current on sheet metal.The electromagnetic field,the magnetic vector potential of pulsed reactor and the distribution of the eddy current on sheet metal were analyzed.The theoretical formula of electromagnetic force was obtained.The results show that the distribution of induced current is related to the size of metal plate;the electromagnetic force on the edge is larger than that at any other position of the plate.The electromagnetic force reaches the positive peak while the discharging current rising up,and the force is zero when the induced current reaches zero,and then the force reaches the negative peak when the discharge current reaches the reverse maximum.

  1. Pulsed electromagnetic field therapy for management of osteoarthritis-related pain, stiffness and physical function: clinical experience in the elderly

    Directory of Open Access Journals (Sweden)

    Iannitti T

    2013-09-01

    Full Text Available Tommaso Iannitti,1,2 Gregorio Fistetto,2 Anna Esposito,2 Valentina Rottigni,2,3 Beniamino Palmieri2,3 1Department of Physiology, University of Kentucky Medical Center, Lexington, KY, USA; 2Poliambulatorio del Secondo Parere, Modena, Italy; 3Department of General Surgery and Surgical Specialties, University of Modena and Reggio Emilia Medical School, Surgical Clinic, Modena, Italy Background: Pulsed electromagnetic field (PEMF therapy has shown promising therapeutic effectiveness on bone- and cartilage-related pathologies, being also safe for management of knee osteoarthritis. Aim: The aim of this study was to investigate the clinical efficacy of a PEMF device for management of knee osteoarthritis in elderly patients. Materials and methods: A total of 33 patients were screened, and 28 patients, aged between 60 and 83 and affected by bilateral knee osteoarthritis, were enrolled in this study. They received PEMF therapy on the right leg for a total of three 30-minute sessions per week for a period of 6 weeks, while the left leg did not receive any treatment and served as control. An intravenous drip containing ketoprofen, sodium clodronate, glucosamine sulfate, calcitonin, and ascorbic acid, for a total volume of 500 mL, was administered during PEMF therapy. At baseline and 3 months post-PEMF therapy, Visual Analog Scale (VAS was used to assess knee pain and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC was used to measure knee pain, stiffness and physical function. Results: Changes in VAS and WOMAC scores were calculated for both knees as baseline minus post-treatment. A two sample Student’s t-test, comparing change in knee-related VAS pain for PEMF-treated leg (49.8 ± 2.03 vs control leg (11 ± 1.1, showed a significant difference in favor of PEMF therapy (P < 0.001. A two sample Student’s t-test comparing change in knee-related WOMAC pain, stiffness, and physical function for PEMF-treated leg (8.5 ± 0.4, 3.5 ± 0.2, 38

  2. Pulsed Electromagnetic Fields in the treatment of fresh scaphoid fractures. A multicenter, prospective, double blind, placebo controlled, randomized trial

    Directory of Open Access Journals (Sweden)

    Poeze Martijn

    2011-05-01

    Full Text Available Abstract Background The scaphoid bone is the most commonly fractured of the carpal bones. In the Netherlands 90% of all carpal fractures is a fracture of the scaphoid bone. The scaphoid has an essential role in functionality of the wrist, acting as a pivot. Complications in healing can result in poor functional outcome. The scaphoid fracture is a troublesome fracture and failure of treatment can result in avascular necrosis (up to 40%, non-union (5-21% and early osteo-arthritis (up to 32% which may seriously impair wrist function. Impaired consolidation of scaphoid fractures results in longer immobilization and more days lost at work with significant psychosocial and financial consequences. Initially Pulsed Electromagnetic Fields was used in the treatment of tibial pseudoarthrosis and non-union. More recently there is evidence that physical forces can also be used in the treatment of fresh fractures, showing accelerated healing by 30% and 71% reduction in nonunion within 12 weeks after initiation of therapy. Until now no double blind randomized, placebo controlled trial has been conducted to investigate the effect of this treatment on the healing of fresh fractures of the scaphoid. Methods/Design This is a multi center, prospective, double blind, placebo controlled, randomized trial. Study population consists of all patients with unilateral acute scaphoid fracture. Pregnant women, patients having a life supporting implanted electronic device, patients with additional fractures of wrist, carpal or metacarpal bones and pre-existing impairment in wrist function are excluded. The scaphoid fracture is diagnosed by a combination of physical and radiographic examination (CT-scanning. Proven scaphoid fractures are treated with cast immobilization and a small Pulsed Electromagnetic Fields bone growth stimulating device placed on the cast. Half of the devices will be disabled at random in the factory. Study parameters are clinical consolidation

  3. Pulsed Electromagnetic Fields in the treatment of fresh scaphoid fractures. A multicenter, prospective, double blind, placebo controlled, randomized trial.

    Science.gov (United States)

    Hannemann, Pascal; Göttgens, Kevin W A; van Wely, Bob J; Kolkman, Karel A; Werre, Andries J; Poeze, Martijn; Brink, Peter R G

    2011-05-06

    The scaphoid bone is the most commonly fractured of the carpal bones. In the Netherlands 90% of all carpal fractures is a fracture of the scaphoid bone. The scaphoid has an essential role in functionality of the wrist, acting as a pivot. Complications in healing can result in poor functional outcome. The scaphoid fracture is a troublesome fracture and failure of treatment can result in avascular necrosis (up to 40%), non-union (5-21%) and early osteo-arthritis (up to 32%) which may seriously impair wrist function. Impaired consolidation of scaphoid fractures results in longer immobilization and more days lost at work with significant psychosocial and financial consequences.Initially Pulsed Electromagnetic Fields was used in the treatment of tibial pseudoarthrosis and non-union. More recently there is evidence that physical forces can also be used in the treatment of fresh fractures, showing accelerated healing by 30% and 71% reduction in nonunion within 12 weeks after initiation of therapy. Until now no double blind randomized, placebo controlled trial has been conducted to investigate the effect of this treatment on the healing of fresh fractures of the scaphoid. This is a multi center, prospective, double blind, placebo controlled, randomized trial. Study population consists of all patients with unilateral acute scaphoid fracture. Pregnant women, patients having a life supporting implanted electronic device, patients with additional fractures of wrist, carpal or metacarpal bones and pre-existing impairment in wrist function are excluded. The scaphoid fracture is diagnosed by a combination of physical and radiographic examination (CT-scanning).Proven scaphoid fractures are treated with cast immobilization and a small Pulsed Electromagnetic Fields bone growth stimulating device placed on the cast. Half of the devices will be disabled at random in the factory.Study parameters are clinical consolidation, radiological consolidation evaluated by CT-scanning, functional

  4. Electromagnetic modeling for gap measurement between nuclear fuel channel and liquid injection nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D. H.; Heo, H.; Jeong, H. G. [KAERI, Taejon (Korea, Republic of)

    2003-10-01

    Fuel channels including Pressure Tube(PT) and Calandria Tube(CT) are important components of Pressurized Heavy Water Reactor(PHWR). A sagging for fuel channel increases by heat and radiation exposure with the increasing operating time. The possibility of contact to Liquid Injection Nozzle(LIN) is thus a critical issue in power plant safety. In order to solve this safety issue, electromagnetic technique was applied to compliment the ultrasonic technology. Electromagnetic fields were investigated for the gap measurement between CT and LIN using computer modeling. We calculated the electromagnetic fields, such as, magnetic flux density, current density near the fuel channel and simulated an impedance and a phase angle in receiving coil for obtaining the optimal inspection parameters, such as, frequency, inter-coil spacing, coil size and configuration. This paper shows that the simulated eddy current signals in variance with the CT/LIN gap can be used for baseline data of experimental electromagnetic technique.

  5. Responses of human normal osteoblast cells and osteoblast-like cell line, MG-63 cells, to pulse electromagnetic field (PEMF

    Directory of Open Access Journals (Sweden)

    Suttatip Kamolmatyakul

    2008-01-01

    Full Text Available The objective of this in vitro study is to investigate the effect of pulsed electromagnetic field (PEMF on cellular proliferation and osteocalcin production of osteoblast-like cell line, MG-63 cells, and human normal osteoblast cells (NHOC obtained from surgical bone specimens. The cells were placed in 24-well culture plates in the amount of 3x104 cell/wells with 2 ml αMEM media supplemented with 10% FBS. The experimental plates were placed between a pair of Helmoltz coils powered by a pulse generator (PEMF, 50 Hz, 1.5 mV/cm in the upper compartment of a dual incubator (Forma. The control plates were placed in the lower compartment of the incubator without Helmotz coils. After three days, the cell proliferation was measured by the method modified from Mossman (J. Immunol Methods 1983; 65: 55-63. Other sets of plates were used for osteocalcin production assessment. Media from these sets were collected after 6 days and assessed for osteocalcin production using ELISA kits. The data were analyzed using a one-way analysis of variance (ANOVA. The results showed that MG-63 cells from the experimental group proliferated significantly more than those from the control group (20% increase, p<0.05. No significant difference in osteocalcin production was detected between the two groups. On the other hand, NHOC from the experimental group produced larger amount of osteocalcin (25% increase, p<0.05 and proliferated significantly more than those from the control group (100% increase, p<0.05. In conclusion, PEMF effect on osteoblasts might depend on their cell type of origin. For osteoblast-like cell line, MG-63 cells, PEMF increased proliferation rate but not osteocalcin production of the cells. However, PEMF stimulation effect on human normal osteoblast cells was most likely associated with enhancement of both osteocalcin production and cell proliferation.

  6. Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure.

    Science.gov (United States)

    Thompson, Gary L; Roth, Caleb C; Kuipers, Marjorie A; Tolstykh, Gleb P; Beier, Hope T; Ibey, Bennett L

    2016-01-29

    Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known to be sequestered for cellular chromosomal function within the nucleus - histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus.

  7. Thermal nuclear pulse simulation at the National Solar Thermal Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, C.P.; Ralph, M.E. (Sandia National Labs., Albuquerque, NM (USA)); Ghanbari, C.M. (Technadyne Engineering Consultants, Inc., Albuquerque, NM (USA)); Oeding, R.; Shaw, K. (PDA Engineering, Albuquerque, NM (USA))

    1991-01-01

    The National Solar Thermal Test Facility (NSTTF) at Sandia National Laboratories in Albuquerque, New Mexico is being used to simulate the thermal pulse from a nuclear weapon on relatively large surfaces. Pulses varying in length from 2 seconds to 7 seconds have been produced. The desired pulse length varies as a function of the yield of the weapon being simulated. The present experiment capability can accommodate samples as large as 1.2 {times} 1.5 meters. Samples can be flat or three-dimensional. Samples exposed have ranged from fabrics (protective clothing) to an aircraft canopy and cockpit system, complete with a mannequin in a flight suit and helmet. In addition, a windowed wind tunnel has been constructed which permits exposure of flight surface materials to thermal transients with air speed of Mach 0.8. The wind tunnel can accommodate samples up to .48 {times} .76 meters or an array of smaller samples. The maximum flux capability of the NSTTF is about 70 calories/cm{sup 2}-sec. A black-body temperature of about 6000 K is produced by the solar beam and is therefore ideal for simulating the nuclear source. 3 refs., 7 figs.

  8. Electromagnetic acceleration of material from a plate hit by a pulsed electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M.

    1998-04-16

    An intense pulsed electron beam traversing a thin metal plate creates a volume of dense plasma. Current flows in this plasma as a result of the charge and magnetic field introduced by the relativistic electrons. A magnetic field may linger after the electron beam pulse because of the conductivity of the material. This field decays by both diffusing out of the conducting matter and causing it to expand. If the magnetized matter is of low density and high conductivity it may expand quickly. Scaling laws for this acceleration are sought by analyzing the idealization of a steady axisymmetric flow. This case simplifies a general formulation based on both Euler`s and Maxwell`s equations. As an example, fluid with conductivity {sigma} = 8 x 10{sup 4} Siemens/m, density {rho} = 8 x 10{sup -3} kg/m{sup 3}, and initially magnetized to B = 1 Tesla can accelerate to v = 10{sup 4} m/s within a distance comparable to L = 1 mm and a time comparable to {sigma}{mu}L{sup 2} = 100 ns, which is the magnetic diffusion time. If instead, {sigma} = 8 x 10{sup 3} Siemens/m and {rho} = 8 x 10{sup -5} kg/m{sup 3} then v = 10{sup 5} m/s with a magnetic diffusion time {sigma}{mu}L{sup 2} = 10 ns. These idealized flows have R{sub M} = {sigma}{mu}vL = 1, where R{sub M} is the magnetic Reynolds number. The target magnetizes by a thermal electric effect.

  9. Nanosecond pulsed electric field induced cytoskeleton, nuclear membrane and telomere damage adversely impact cell survival.

    Science.gov (United States)

    Stacey, M; Fox, P; Buescher, S; Kolb, J

    2011-10-01

    We investigated the effects of nanosecond pulsed electric fields (nsPEF) on three human cell lines and demonstrated cell shrinkage, breakdown of the cytoskeleton, nuclear membrane and chromosomal telomere damage. There was a differential response between cell types coinciding with cell survival. Jurkat cells showed cytoskeleton, nuclear membrane and telomere damage that severely impacted cell survival compared to two adherent cell lines. Interestingly, disruption of the actin cytoskeleton in adherent cells prior to nsPEF exposure significantly reduced cell survival. We conclude that nsPEF applications are able to induce damage to the cytoskeleton and nuclear membrane. Telomere sequences, regions that tether and stabilize DNA to the nuclear membrane, are severely compromised as measured by a pan-telomere probe. Internal pore formation following nsPEF applications has been described as a factor in induced cell death. Here we suggest that nsPEF induced physical changes to the cell in addition to pore formation need to be considered as an alternative method of cell death. We suggest nsPEF electrochemical induced depolymerization of actin filaments may account for cytoskeleton and nuclear membrane anomalies leading to sensitization.

  10. Ultrafast control of nuclear spins using only microwave pulses: towards switchable solid-state quantum gates

    CERN Document Server

    Mitrikas, George; Papavassiliou, Georgios

    2009-01-01

    Since the idea of quantum information processing (QIP) fascinated the scientific community, electron and nuclear spins have been regarded as promising candidates for quantum bits (qubits). A fundamental challenge in the realization of a solid-state quantum computer is the construction of fast and reliable two-qubit quantum gates. Of particular interest in this direction are hybrid systems of electron and nuclear spins, where the two qubits are coupled through the hyperfine interaction. However, the significantly different gyromagnetic ratios of electron and nuclear spins do not allow for their coherent manipulation at the same time scale. Here we demonstrate the control of the alpha-proton nuclear spin, I=1/2, coupled to the stable radical CH(COOH)2, S=1/2, in a gamma-irradiated malonic acid single crystal using only microwave pulses. We show that, depending on the state of the electron spin (mS=+1/2 or -1/2), the nuclear spin can be locked in a desired state or oscillate between mI=+1/2 and mI=-1/2 on the na...

  11. [Effect of ATP and glutaminic acid on carbohydrate-energy and nitrogen metabolism in the rat brain and liver under the effect of pulsed electromagnetic field].

    Science.gov (United States)

    Mishchenko, L I; Kolodub, F A

    1975-01-01

    Oxidative phosphorylation, content of lactate, creatine phosphate, ammonia and glutamine were studied as affected by ATP and glutaminic acid in the brain and liver of rat subjected to the action of the pulsed electromagnetic field of 7 kHz frequency (72 kA/m, 15 seances). ATP (1 mg per 100 g of weight) was found to have a normalizing effect on the processes of nitrogen metabolism in the rat brain, ATP increasing the intenstiy of the oxidative phosphorylation in the tissues of intact rats, has no analogous influence on the irradiated animals. With administration of glutaminic acid (5 mg per 100 g of weight) the processes of oxidative phosphorylation and nitrogen metabolism, disturbed under the effect of the pulsed electromagnetic field are normalized.

  12. A Pulsed Electromagnetic Field Protects against Glutamate-Induced Excitotoxicity by Modulating the Endocannabinoid System in HT22 Cells

    Science.gov (United States)

    Li, Xin; Xu, Haoxiang; Lei, Tao; Yang, Yuefan; Jing, Da; Dai, Shuhui; Luo, Peng; Xu, Qiaoling

    2017-01-01

    Glutamate-induced excitotoxicity is common in the pathogenesis of many neurological diseases. A pulsed electromagnetic field (PEMF) exerts therapeutic effects on the nervous system, but its specific mechanism associated with excitotoxicity is still unknown. We investigated the role of PEMF exposure in regulating glutamate-induced excitotoxicity through the endocannabinoid (eCB) system. PEMF exposure improved viability of HT22 cells after excitotoxicity and reduced lactate dehydrogenase release and cell death. An eCB receptor 1 (CB1R) specific inhibitor suppressed the protective effects of PEMF exposure, even though changes in CB1R expression were not observed. Elevation of N-arachidonylethanolamide (AEA) and 2-arachidonylglycerol (2-AG) following PEMF exposure indicated that the neuroprotective effects of PEMF were related to modulation of the eCB metabolic system. Furthermore, CB1R/ERK signaling was shown to be an important downstream pathway of PEMF in regulating excitotoxicity. These results suggest that PEMF exposure leads to neuroprotective effects against excitotoxicity by facilitating the eCB/CB1R/ERK signaling pathway. Therefore, PEMF may be a potential physical therapeutic technique for preventing and treating neurological diseases. PMID:28220060

  13. Induction of neuritogenesis in PC12 cells by a pulsed electromagnetic field via MEK-ERK1/2 signaling.

    Science.gov (United States)

    Kudo, Tada-aki; Kanetaka, Hiroyasu; Shimizu, Yoshinaka; Abe, Toshihiko; Mori, Hitoshi; Mori, Kazumi; Suzuki, Eizaburo; Takagi, Toshiyuki; Izumi, Shin-ichi

    2013-01-01

    We examined the regulation of neuritogenesis by a pulsed electromagnetic field (PEMF) in rat PC12 pheochromocytoma cells, which can be induced to differentiate into neuron-like cells with elongated neurites by inducers such as nerve growth factor (NGF). Plated PC12 cells were exposed to a single PEMF (central magnetic flux density, 700 mT; frequency, 0.172 Hz) for up to 12 h per day and were then evaluated for extent of neuritogenesis or acetylcholine esterase (AChE) activity. To analyze the mechanism underlying the effect of the PEMF on the cells, its effects on intracellular signaling were examined using the ERK kinase (MEK) inhibitors PD098059 and U0126 (U0124 was used as a negative control for U0126). The number of neurite-bearing PC12 cells and AChE activity increased after PEMF exposure without the addition of other inducers of neuritogenesis. Additionally, PEMF exposure induced sustained activation of ERK1/2 in PC12 cells, but not in NR8383 rat alveolar macrophages. Furthermore, U0126 strongly inhibited PEMF-dependent ERK1/2 activation and neuritogenesis. The PEMF-dependent neuritogenesis was also suppressed by PD098059, but not U0124. These results suggest that PEMF stimulation independently induced neuritogenesis and that activation of MEK-ERK1/2 signaling was induced by a cell-type-dependent mechanism required for PEMF-dependent neuritogenesis in PC12 cells.

  14. Electrical Resistance of Nb3Sn/Cu Splices Produced by Electromagnetic Pulse Technology and Soft Soldering

    CERN Document Server

    Schoerling, D; Scheuerlein, C; Atieh, S; Schaefer, R

    2011-01-01

    The electrical interconnection of Nb3Sn/Cu strands is a key issue for the construction of Nb3Sn based damping ring wigglers and insertion devices for third generation light sources. We compare the electrical resistance of Nb3Sn/Cu splices manufactured by solid state welding using Electromagnetic Pulse Technology (EMPT) with that of splices produced by soft soldering with two different solders. The resistance of splices produced by soft soldering depends strongly on the resistivity of the solder alloy at the operating temperature. By solid state welding splice resistances below 10 nOhm can be achieved with 1 cm strand overlap length only, which is about 4 times lower than the resistance of Sn96Ag4 soldered splices with the same overlap length. The comparison of experimental results with Finite Element simulations shows that the electrical resistance of EMPT welded splices is determined by the resistance of the stabilizing copper between the superconducting filaments and confirms that welding of the strand matr...

  15. Low frequency pulsed electromagnetic field affects proliferation, tissue-specific gene expression, and cytokines release of human tendon cells.

    Science.gov (United States)

    de Girolamo, L; Stanco, D; Galliera, E; Viganò, M; Colombini, A; Setti, S; Vianello, E; Corsi Romanelli, M M; Sansone, V

    2013-07-01

    Low frequency pulsed electromagnetic field (PEMF) has proven to be effective in the modulation of bone and cartilage tissue functional responsiveness, but its effect on tendon tissue and tendon cells (TCs) is still underinvestigated. PEMF treatment (1.5 mT, 75 Hz) was assessed on primary TCs, harvested from semitendinosus and gracilis tendons of eight patients, under different experimental conditions (4, 8, 12 h). Quantitative PCR analyses were conducted to identify the possible effect of PEMF on tendon-specific gene transcription (scleraxis, SCX and type I collagen, COL1A1); the release of pro- and anti-inflammatory cytokines and of vascular endothelial growth factor (VEGF) was also assessed. Our findings show that PEMF exposure is not cytotoxic and is able to stimulate TCs' proliferation. The increase of SCX and COL1A1 in PEMF-treated cells was positively correlated to the treatment length. The release of anti-inflammatory cytokines in TCs treated with PEMF for 8 and 12 h was significantly higher in comparison with untreated cells, while the production of pro-inflammatory cytokines was not affected. A dramatically higher increase of VEGF-A mRNA transcription and of its related protein was observed after PEMF exposure. Our data demonstrated that PEMF positively influence, in a dose-dependent manner, the proliferation, tendon-specific marker expression, and release of anti-inflammatory cytokines and angiogenic factor in a healthy human TCs culture model.

  16. Mechanical Stimulation (Pulsed Electromagnetic Fields "PEMF" and Extracorporeal Shock Wave Therapy "ESWT") and Tendon Regeneration: A Possible Alternative.

    Science.gov (United States)

    Rosso, Federica; Bonasia, Davide E; Marmotti, Antonio; Cottino, Umberto; Rossi, Roberto

    2015-01-01

    The pathogenesis of tendon degeneration and tendinopathy is still partially unclear. However, an active role of metalloproteinases (MMP), growth factors, such as vascular endothelial growth factor (VEGF) and a crucial role of inflammatory elements and cytokines was demonstrated. Mechanical stimulation may play a role in regulation of inflammation. In vitro studies demonstrated that both pulsed electromagnetic fields (PEMF) and extracorporeal shock wave therapy (ESWT) increased the expression of pro-inflammatory cytokine such as interleukin (IL-6 and IL-10). Moreover, ESWT increases the expression of growth factors, such as transforming growth factor β(TGF-β), (VEGF), and insulin-like growth factor 1 (IGF1), as well as the synthesis of collagen I fibers. These pre-clinical results, in association with several clinical studies, suggest a potential effectiveness of ESWT for tendinopathy treatment. Recently PEMF gained popularity as adjuvant for fracture healing and bone regeneration. Similarly to ESWT, the mechanical stimulation obtained using PEMFs may play a role for treatment of tendinopathy and for tendon regeneration, increasing in vitro TGF-β production, as well as scleraxis and collagen I gene expression. In this manuscript the rational of mechanical stimulations and the clinical studies on the efficacy of extracorporeal shock wave (ESW) and PEMF will be discussed. However, no clear evidence of a clinical value of ESW and PEMF has been found in literature with regards to the treatment of tendinopathy in human, so further clinical trials are needed to confirm the promising hypotheses concerning the effectiveness of ESWT and PEMF mechanical stimulation.

  17. Pulsed Electromagnetic Field Stimulation Promotes Anti-cell Proliferative Activity in Doxorubicin-treated Mouse Osteosarcoma Cells.

    Science.gov (United States)

    Muramatsu, Yoshitaka; Matsui, Takuya; Deie, Masataka; Sato, Keiji

    2017-01-02

    We aimed to investigate the synergistic effects of pulsed electromagnetic field (PEMF) and doxorubicin therapy in a mouse osteosarcoma cell line (LM8 cells) in vitro. The effects of PEMF (5 mT, 200 Hz) of different durations and doxorubicin on the proliferative activity of LM8 cells were measured by the MTT assay. Apoptotic-related factors such as cell-cycle phase, mitochondrial membrane potential, and caspase 3/7 activity were investigated using 4',6-diamidino-2-phenylindole staining and apoptosis kits. Identification of intracellular signaling molecules induced by the combination was comprehensively explored using a stress and apoptosis-related protein array kit. PEMF enhanced the inhibition of cell proliferation mediated by doxorubicin but did not affect the cell cycle, mitochondrial membrane potential, or doxorubicin-induced G2/M arrest. The combination of PEMF and doxorubicin altered a few signaling molecules. PEMF tended to reduce the doxorubicin-induced decrease of phosphorylated BAD, while reducing the increased expression of total IĸB and phosphorylated-CHK1 induced by doxorubicin. Our results indicate that combination of PEMF and doxorubicin could be a novel chemotherapeutic strategy. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  18. Autoradiographic study of the effects of pulsed electromagnetic fields on bone and cartilage growth in juvenile rats.

    Science.gov (United States)

    Wilmot, J J; Chiego, D J; Carlson, D S; Hanks, C T; Moskwa, J J

    1993-01-01

    Application of pulsed electromagnetic fields (PEMF) has been used in growth and repair of non-union bone fractures. The similarities between the fibrocartilage callus in non-union bone fractures and the secondary cartilage in the mandibular condyle, both histologically and functionally, lead naturally to study the effects of PEMFs on growth in the condyle. The purposes of this study were: (1) to describe the effects of PEMFs on the growth of the condyle using autoradiography, [3H]-proline and [3H]-thymidine, and (2) to differentiate between the effects of the magnetic and electrical components of the field. Male pre-adolescent Sprague-Dawley rats (28 days old) were divided into three experimental groups of five animals each: (1) PEMF-magnetic (M), (2) PEMF-electrical (E) and (3) control, and were examined at three different times-3, 7 and 14 days of exposure. Each animal was exposed to the field for 8 h per day. Histological coronal sections were processed for quantitative autoradiography to determine the mitotic activity of the condylar cartilage and the amount of bone deposition. The PEMF (magnetic or electrical) had statistically significant effects only on the thickness of the articular zone, with the thickness in the PEMF-M group being the most reduced. Length of treatment was associated with predictable significant changes in the thickness of the condylar cartilage zones and the amount of bone deposition.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Effects of pulsed electromagnetic fields on peripheral blood circulation in people with diabetes: A randomized controlled trial.

    Science.gov (United States)

    Sun, Jiahui; Kwan, Rachel Lai-Chu; Zheng, Yongping; Cheing, Gladys Lai-Ying

    2016-07-01

    Cutaneous blood flow provides nourishment that plays an essential role in maintaining skin health. We examined the effects of pulsed electromagnetic fields (PEMFs) on cutaneous circulation of dorsal feet. Twenty-two patients with diabetes mellitus (DM) and 21 healthy control subjects were randomly allocated to receive either PEMFs or sham PEMFs (0.5 mT, 12 Hz, 30 min). Blood flow velocity and diameter of the small vein were examined by using ultrasound biomicroscopy; also, microcirculation at skin over the base of the 1st metatarsal bone (Flux1) and distal 1st phalange (Flux2) was measured by laser Doppler flowmetry before and after intervention. Results indicated that PEMFs produced significantly greater changes in blood flow velocity of the smallest observable vein than did sham PEMFs (both P < 0.05) in both types of subjects. However, no significant difference was found in changes of vein diameter, nor in Flux1 and Flux2, between PEMFs and sham PEMFs groups in subjects with or without DM. We hypothesized that PEMFs would increase blood flow velocity of the smallest observable vein in people with or without DM. Bioelectromagnetics. 37:290-297, 2016. © 2016 Wiley Periodicals, Inc.

  20. Neuroprotective effects of sevoflurane against electromagnetic pulse-induced brain injury through inhibition of neuronal oxidative stress and apoptosis.

    Directory of Open Access Journals (Sweden)

    Bin Deng

    Full Text Available Electromagnetic pulse (EMP causes central nervous system damage and neurobehavioral disorders, and sevoflurane protects the brain from ischemic injury. We investigated the effects of sevoflurane on EMP-induced brain injury. Rats were exposed to EMP and immediately treated with sevoflurane. The protective effects of sevoflurane were assessed by Nissl staining, Fluoro-Jade C staining and electron microscopy. The neurobehavioral effects were assessed using the open-field test and the Morris water maze. Finally, primary cerebral cortical neurons were exposed to EMP and incubated with different concentration of sevoflurane. The cellular viability, lactate dehydrogenase (LDH release, superoxide dismutase (SOD activity and malondialdehyde (MDA level were assayed. TUNEL staining was performed, and the expression of apoptotic markers was determined. The cerebral cortexes of EMP-exposed rats presented neuronal abnormalities. Sevoflurane alleviated these effects, as well as the learning and memory deficits caused by EMP exposure. In vitro, cell viability was reduced and LDH release was increased after EMP exposure; treatment with sevoflurane ameliorated these effects. Additionally, sevoflurane increased SOD activity, decreased MDA levels and alleviated neuronal apoptosis by regulating the expression of cleaved caspase-3, Bax and Bcl-2. These findings demonstrate that Sevoflurane conferred neuroprotective effects against EMP radiation-induced brain damage by inhibiting neuronal oxidative stress and apoptosis.

  1. Effect of pulsed electromagnetic field therapy on experimental pain: A double-blind, randomized study in healthy young adults.

    Science.gov (United States)

    Beaulieu, Karen; Beland, Patricia; Pinard, Marilee; Handfield, Guilène; Handfield, Nicole; Goffaux, Philippe; Corriveau, Hélène; Léonard, Guillaume

    2016-01-01

    Previous studies suggested that pulsed electromagnetic field (PEMF) therapy can decrease pain. To date, however, it remains difficult to determine whether the analgesic effect observed in patients are attributable to a direct effect of PEMF on pain or to an indirect effect of PEMF on inflammation and healing. In the present study, we used an experimental pain paradigm to evaluate the direct effect of PEMF on pain intensity, pain unpleasantness, and temporal summation of pain. Twenty-four healthy subjects (mean age 22 ± 2 years; 9 males) participated in the experiment. Both real and sham PEMF were administered to every participant using a randomized, double-blind, cross-over design. For each visit, PEMF was applied for 10 minutes on the right forearm using a portable device. Experimental pain was evoked before (baseline) and after PEMF with a 9 cm(2) Pelletier-type thermode, applied on the right forearm (120 s stimulation; temperature individually adjusted to produce moderate baseline pain). Pain intensity and unpleasantness were evaluated using a 0-100 numerical pain rating scale. Temporal summation was evaluated by comparing pain intensity ratings obtained at the end of tonic nociceptive stimulation (120 s) with pain intensity ratings obtained after 60 s of stimulation. When compared to baseline, there was no change in pain intensity and unpleasantness following the application of real or sham PEMF. PEMF did not affect temporal summation. The present observations suggest that PEMF does not directly influence heat pain perception in healthy individuals.

  2. Compact Short-Pulsed Electron Linac Based Neutron Sources for Precise Nuclear Material Analysis

    Science.gov (United States)

    Uesaka, M.; Tagi, K.; Matsuyama, D.; Fujiwara, T.; Dobashi, K.; Yamamoto, M.; Harada, H.

    2015-10-01

    An X-band (11.424GHz) electron linac as a neutron source for nuclear data study for the melted fuel debris analysis and nuclear security in Fukushima is under development. Originally we developed the linac for Compton scattering X-ray source. Quantitative material analysis and forensics for nuclear security will start several years later after the safe settlement of the accident is established. For the purpose, we should now accumulate more precise nuclear data of U, Pu, etc., especially in epithermal (0.1-10 eV) neutrons. Therefore, we have decided to modify and install the linac in the core space of the experimental nuclear reactor "Yayoi" which is now under the decommission procedure. Due to the compactness of the X-band linac, an electron gun, accelerating tube and other components can be installed in a small space in the core. First we plan to perform the time-of-flight (TOF) transmission measurement for study of total cross sections of the nuclei for 0.1-10 eV energy neutrons. Therefore, if we adopt a TOF line of less than 10m, the o-pulse length of generated neutrons should be shorter than 100 ns. Electronenergy, o-pulse length, power, and neutron yield are ~30 MeV, 100 ns - 1 micros, ~0.4 kW, and ~1011 n/s (~103 n/cm2/s at samples), respectively. Optimization of the design of a neutron target (Ta, W, 238U), TOF line and neutron detector (Ce:LiCAF) of high sensitivity and fast response is underway. We are upgrading the electron gun and a buncher to realize higher current and beam power with a reasonable beam size in order to avoid damage of the neutron target. Although the neutron flux is limited in case of the X-band electron linac based source, we take advantage of its short pulse aspect and availability for nuclear data measurement with a short TOF system. First, we form a tentative configuration in the current experimental room for Compton scattering in 2014. Then, after the decommissioning has been finished, we move it to the "Yayoi" room and perform

  3. Design and Fabrication of Helmholtz Coils to Study the Effects of Pulsed Electromagnetic Fields on the Healing Process in Periodontitis: Preliminary Animal Results

    Directory of Open Access Journals (Sweden)

    Haghnegahdar A

    2014-09-01

    Full Text Available Background: Effects of electromagnetic fields on healing have been investigated for centuries. Substantial data indicate that exposure to electromagnetic field can lead to enhanced healing in both soft and hard tissues. Helmholtz coils are devices that generate pulsed electromagnetic fields (PEMF. Objective: In this work, a pair of Helmholtz coils for enhancing the healing process in periodontitis was designed and fabricated. Method: An identical pair of square Helmholtz coils generated the 50 Hz magnetic field. This device was made up of two parallel coaxial circular coils (100 turns in each loop, wound in series which were separated from each other by a distance equal to the radius of one coil (12.5 cm. The windings of our Helmholtz coil was made of standard 0.95mm wire to provide the maximum possible current. The coil was powered by a function generator. Results: The Helmholtz Coils generated a uniform magnetic field between its coils. The magnetic field strength at the center of the space between two coils was 97.6 μT. Preliminary biological studies performed on rats show that exposure of laboratory animals to pulsed electromagnetic fields enhanced the healing of periodontitis. Conclusion: Exposure to PEMFs can lead to stimulatory physiological effects on cells and tissues such as enhanced healing of periodontitis.

  4. Comparison of ATLOG and Xyce for Bell Labs Electromagnetic Pulse Excitation of Finite-Long Dissipative Conductors over a Ground Plane.

    Energy Technology Data Exchange (ETDEWEB)

    campione, salvatore; Warne, Larry K.; Schiek, Richard; Basilio, Lorena I.

    2017-09-01

    This report details the modeling results for the response of a finite-length dissipative conductor interacting with a conducting ground to the Bell Labs electromagnetic pulse excitation. We use both a frequency-domain and a time-domain method based on transmission line theory through a code we call ATLOG - Analytic Transmission Line Over Ground. Results are compared to the circuit simulator Xyce for selected cases. Intentionally Left Blank

  5. Analysis of ringing effects due to magnetic core materials in pulsed nuclear magnetic resonance circuits

    Energy Technology Data Exchange (ETDEWEB)

    Prabhu Gaunkar, N., E-mail: neelampg@iastate.edu; Bouda, N. R. Y.; Nlebedim, I. C.; Hadimani, R. L.; Mina, M.; Jiles, D. C. [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Bulu, I.; Ganesan, K.; Song, Y. Q. [Schlumberger-Doll Research, Cambridge, Massachusetts 02139 (United States)

    2015-05-07

    This work presents investigations and detailed analysis of ringing in a non-resonant pulsed nuclear magnetic resonance (NMR) circuit. Ringing is a commonly observed phenomenon in high power switching circuits. The oscillations described as ringing impede measurements in pulsed NMR systems. It is therefore desirable that those oscillations decay fast. It is often assumed that one of the causes behind ringing is the role of the magnetic core used in the antenna (acting as an inductive load). We will demonstrate that an LRC subcircuit is also set-up due to the inductive load and needs to be considered due to its parasitic effects. It is observed that the parasitics associated with the inductive load become important at certain frequencies. The output response can be related to the response of an under-damped circuit and to the magnetic core material. This research work demonstrates and discusses ways of controlling ringing by considering interrelationships between different contributing factors.

  6. In vivo setup characterization for pulsed electromagnetic field exposure at 3 GHz

    Science.gov (United States)

    Collin, A.; Perrin, A.; Cretallaz, C.; Pla, S.; Arnaud-Cormos, D.; Debouzy, J. C.; Leveque, P.

    2016-08-01

    An in vivo setup for pulsed electric field exposure at 3 GHz is proposed and characterized in this work. The exposure system allows far field, whole-body exposure of six animals placed in Plexiglas cages with a circular antenna. Chronic exposures under 18 W incident average power (1-4 kW peak power) and acute exposures under 56 W incident average power (4.7 kW peak power) were considered. Numerical and experimental dosimetry of the setup allowed the accurate calculation of specific absorption rate (SAR) distributions under various exposure conditions. From rat model numerical simulations, the whole-body mean SAR values were 1.3 W kg-1 under chronic exposures and 4.1 W kg-1 under acute exposure. The brain-averaged SAR value was 1.8 W kg-1 and 5.7 W kg-1 under chronic and acute exposure, respectively. Under acute exposure conditions, a 10 g specific absorption of 1.8  ±  1.1 mJ · kg-1 value was obtained. With temperature rises below 0.8 °C, as measured or simulated on a gel phantom under typical in vivo exposures, this exposure system provides adequate conditions for in vivo experimental investigations under non-thermal conditions.

  7. A dual mode pulsed electro-magnetic cell stimulator produces acceleration of myogenic differentiation.

    Science.gov (United States)

    Leon-Salas, Walter D; Rizk, Hatem; Mo, Chenglin; Weisleder, Noah; Brotto, Leticia; Abreu, Eduardo; Brotto, Marco

    2013-04-01

    This paper presents the design and test of a dual-mode electric and magnetic biological stimulator (EM-Stim). The stimulator generates pulsing electric and magnetic fields at programmable rates and intensities. While electric and magnetic stimulators have been reported before, this is the first device that combines both modalities. The ability of the dual stimulation to target bone and muscle tissue simultaneously has the potential to improve the therapeutic treatment of osteoporosis and sarcopenia. The device is fully programmable, portable and easy to use, and can run from a battery or a power supply. The device can generate magnetic fields of up to 1.6 mT and output voltages of +/- 40 V. The EM-Stim accelerated myogenic differentiation of myoblasts into myotubes as evidenced by morphometric, gene expression, and protein content analyses. Currently, there are many patents concerned with the application of single electrical or magnetic stimulation, but none that combine both simultaneously. However, we applied for and obtained a provisional patent for new device to fully explore its therapeutic potential in pre-clinical models.

  8. Time-Domain Modeling of Electromagnetic Pulses Returned from Targets in Dispersive and Dissipative Media

    Science.gov (United States)

    Gaunaurd, G. C.; Strifors, H. C.; Sullivan, A.

    2008-06-01

    Using a Method-of-Moments (MoM) code, we earlier simulated ultra-wideband (UWB) returned echoes from two targets, one penetrable and one impenetrable, buried in a soil with known electric properties. The simple shape of mines, coupled with their predictable deployment in the ground, has also provided a fundamental understanding of the underlying backscatter phenomenology. In particular, the backscattered waveform from a mine can be decomposed into a collection of closely spaced copies of an elemental wave object with different amplitudes and time delays. This wave object is here defined as the derivative of the waveform incident on the target. The spacing of the copies or replicas of the wave object could be determined by the round trip time delay between scattering centers. This methodology was previously applied to impenetrable targets and is now applied also to a penetrable target. The previously computed returns from each target for a given incident pulse are modeled by a few copies of the elemental wave object with the time delay and amplitude of each copy taken as unknown parameters. These parameters are then determined by minimizing in the least square sense the difference between the MoM computed signal and the model signal using the differential evolution method (DEM). The methodology is extended by way of our previously developed target translated method (TTM) to approximate the computation of the backscattered model signal when the target is buried at a different depth in the soil with a different moisture content.

  9. Pulse

    Science.gov (United States)

    ... resting for at least 10 minutes. Take the exercise heart rate while you are exercising. ... pulse rate can help determine if the person's heart is pumping. Pulse ... rate gives information about your fitness level and health.

  10. Simplified method for measuring the response time of scram release electromagnet in a nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Patri, Sudheer, E-mail: patri@igcar.gov.in; Mohana, M.; Kameswari, K.; Kumar, S. Suresh; Narmadha, S.; Vijayshree, R.; Meikandamurthy, C.; Venkatesan, A.; Palanisami, K.; Murthy, D. Thirugnana; Babu, B.; Prakash, V.; Rajan, K.K.

    2015-04-15

    Highlights: • An alternative method for estimating the electromagnet clutch release time. • A systematic approach to develop a computer based measuring system. • Prototype tests on the measurement system. • Accuracy of the method is ±6% and repeatability error is within 2%. - Abstract: The delay time in electromagnet clutch release during a reactor trip (scram action) is an important safety parameter, having a bearing on the plant safety during various design basis events. Generally, it is measured using current decay characteristics of electromagnet coil and its energising circuit. A simplified method of measuring the same in a Sodium cooled fast reactors (SFR) is proposed in this paper. The method utilises the position data of control rod to estimate the delay time in electromagnet clutch release. A computer based real time measurement system for measuring the electromagnet clutch delay time is developed and qualified for retrofitting in prototype fast breeder reactor. Various stages involved in the development of the system are principle demonstration, experimental verification of hardware capabilities and prototype system testing. Tests on prototype system have demonstrated the satisfactory performance of the system with intended accuracy and repeatability.

  11. Electromagnetic interactions

    CERN Document Server

    Bosanac, Slobodan Danko

    2016-01-01

    This book is devoted to theoretical methods used in the extreme circumstances of very strong electromagnetic fields. The development of high power lasers, ultrafast processes, manipulation of electromagnetic fields and the use of very fast charged particles interacting with other charges requires an adequate theoretical description. Because of the very strong electromagnetic field, traditional theoretical approaches, which have primarily a perturbative character, have to be replaced by descriptions going beyond them. In the book an extension of the semi-classical radiation theory and classical dynamics for particles is performed to analyze single charged atoms and dipoles submitted to electromagnetic pulses. Special attention is given to the important problem of field reaction and controlling dynamics of charges by an electromagnetic field.

  12. Electromagnetic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Bosanac, Slobodan Danko [Ruder Boskovic Institute, Zagreb (Croatia). Physical Chemistry

    2016-07-01

    This book is devoted to theoretical methods used in the extreme circumstances of very strong electromagnetic fields. The development of high power lasers, ultrafast processes, manipulation of electromagnetic fields and the use of very fast charged particles interacting with other charges requires an adequate theoretical description. Because of the very strong electromagnetic field, traditional theoretical approaches, which have primarily a perturbative character, have to be replaced by descriptions going beyond them. In the book an extension of the semi-classical radiation theory and classical dynamics for particles is performed to analyze single charged atoms and dipoles submitted to electromagnetic pulses. Special attention is given to the important problem of field reaction and controlling dynamics of charges by an electromagnetic field.

  13. MnSOD expression inhibited by electromagnetic pulse radiation in the rat testis.

    Science.gov (United States)

    Zeng, LiHua; Ji, XiTuan; Zhang, YanJun; Miao, Xia; Zou, ChangXu; Lang, HaiYang; Zhang, Jie; Li, YuRong; Wang, XiaoWu; Qi, HongXing; Ren, DongQin; Guo, GuoZhen

    2011-12-01

    Male Sprague Dawley rats were exposed to EMP irradiation of 100 kV/m peak-to-peak e-field intensity and different numbers of pulses. Rat sperm samples were prepared for analysis of sperm qualities; Testes were assessed by transmission electron microscopy and serum hormone concentrations were examined by radioimmunoassay; Enzymatic activities of Total-superoxide dismutase(T-SOD) and manganese-superoxide dismutase (MnSOD), the mRNA levels of MnSOD and cuprozinc-superoxide dismutase (CuZnSOD), and the density of malondialdehyde (MDA) were also determined. EMP irradiation did not affect spermatozoon morphology, micronucleus formation rate, sperm number or viability, but the acrosin reaction rate decreased at 24 h and 48 h and recovered by 72 h after irradiation as compared to the controls. The ultrastructure of rat testis displayed more serious damage at 24 h than at other time points (6 h, 12 h, 48 h). Serum levels of luteotrophic hormone (LH) and testosterone (T) were elevated in irradiated rats as compared to controls. After irradiation, enzymatic activities of T-SOD and MnSOD were reduced by 24 h, consistent with the changes observed in MnSOD mRNA expression; MDA content increased at 6 h in turn. These studies have quantified the morphological damage and dysfunction in the rat reproductive system induced by EMP. The mechanism of EMP induced damage may be associated with the inhibition of MnSOD expression.

  14. Effect of polarization on the structure of electromagnetic field and spatiotemporal distribution of $e^+e^-$ pairs by colliding laser pulses

    CERN Document Server

    Banerjee, Chitradip

    2016-01-01

    Electron-positron pair production by means of vacuum polarization in the presence of strong electromagnetic (EM) field of two counterpropagating laser pulses is studied. A 3-dimensional model of the focused laser pulses based on the solution of the Maxwell's equations proposed by Narozhny and Fofanov is used to find the structure of EM field of the circularly polarized counterpropagating pulses. Analytical calculations show that the electric and magnetic fields are almost parallel to each other in the focal region when pulses are completely transverse either in electric (e-wave) or magnetic (h-wave) field. On the other hand the electric and magnetic fields are almost orthogonal when the counterpropagating pulses are made up of equal mixture of e- and h- polarized waves. It is found that while the latter configuration of the colliding pulses has much larger threshold for pair production it can provide much shorter electron/positron pulses compared to the former case. The dependence of pair production and its s...

  15. The Analysis of the Field Application Methodology of Electromagnetic Ultrasonic Testing for Piping in Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chi Seung; Joo, Keum Jong; Choi, Jung Kweun; Um, Byung Kook; Park, Jea Suk [Korea Advanced Ispection Technology Co., Daejeon (Korea, Republic of)

    2008-08-15

    Nuclear plant piping is classified as the safety class and non-safety class piping in usual. Safety class piping has been examined in accordance with ASME Section XI and V during PSI/ISI using RT, UT, PT, ECT, etc and evaluated periodically for integrity. But failures in piping had reported at non-welded parts and non-safety class pipings as well as the safety class pipings. The existing NDT methods are suitable for the specific parts for instance weldments to inspect but difficult to examine all parts (total coverage) of pipe line and very expensive in cost and consume the time. And also inspection using those methods is difficult and limited for the parts which are complex configuration, embedded under ground and installed at high radiation area in nuclear power plants. In order to inspect all parts of long range piping systems and reduce the inspection time and cost, the electromagnetic ultrasonic inspection technology is suitable and effective. The electromagnetic ultrasonic method can cover more than 50 m apart from sensor at one time without moving the sensor and examined the parts which are in difficulties for accessibility, for example, high radiation area, insulated components and embedded under ground.

  16. Z箍缩内爆产生的电磁脉冲辐射%Electromagnetic pulse emission produced by Z pinch implosions

    Institute of Scientific and Technical Information of China (English)

    但加坤; 计策; 何安; 夏明鹤; 丰树平; 王勐; 谢卫平; 任晓东; 黄显宾; 张思群; 周少彤; 段书超; 欧阳凯; 蔡红春; 卫兵

    2013-01-01

    讨论了Z箍缩内爆产生的低频电磁脉冲的辐射特性.Z箍缩驱动金属丝阵或固体套筒高速内爆,部分磁能通过与负载的运动耦合而向外辐射.理论结果表明,电磁脉冲辐射功率由电流和内爆轨迹共同决定.在中国工程物理研究院流体物理研究所的初级实验平台上开展了负载电流为7 MA,10%-90%上升时间65 ns的丝阵Z箍缩实验,根据实验测得的电流和内爆轨迹得到了电磁脉冲的辐射功率和频谱.电磁脉冲峰值功率约为1 GW,能量约为0.5 J,能量转换效率约为10-7;峰值频率位于20-70 MHz,具有较宽的辐射频谱.电磁脉冲辐射参数远小于软X射线辐射参数(峰值功率为50 TW,能量为0.5 MJ).在弱相对论条件下,电磁脉冲辐射功率近似地正比于电流的6次方,随电流急剧增大.软X射线辐射是丝阵Z箍缩过程中的主要能量转换形式,本文的研究结论表明,在更高的驱动电流下,电磁脉冲辐射将提供另一种重要的能量转换途径,势必会对诊断设备造成严重影响;此外,这类强电磁脉冲在其他领域也具有潜在的应用价值.%In this paper, we represent the radiation characteristics of electromagnetic pulse generated by Z pinch implosion. Magnetic energy which couples with motions of metallic wire arrays or solid liners driven by Z pinch can radiate away. Theoretical results indicate that the radiation power of electromagnetic pulse is determined by both load current and implosion trace. Experiments are carried on primary test stand facility at Institute of Fluid Physics where a current rising to 7 MA in (10%-90%) 65 ns is used to drive a wire array Z pinch. The measured load current and implosion trace show that the Z pinch can deliver about 1 GW, 10 ns full width, 20-70 MHz central frequency, broadband electromagnetic pulse with an energy conversion efficiency of 10-7 . Parameters of electromagnetic pulse are much smaller than those of X-ray with a power of 50 TW

  17. Deuterium–deuterium nuclear reaction induced by high intensity laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Torrisi, L., E-mail: lorenzo.torrisi@unime.it [INFN-LNS, Via S. Sofia 44, 95123 Catania (Italy); Dip.to di Fisica, Università di Messina, V.le F.S. D’Alcontres 31, 98166 S. Agata, Messina (Italy); Cavallaro, S.; Cutroneo, M.; Giuffrida, L. [INFN-LNS, Via S. Sofia 44, 95123 Catania (Italy); Dip.to di Fisica, Università di Messina, V.le F.S. D’Alcontres 31, 98166 S. Agata, Messina (Italy); Krasa, J.; Margarone, D.; Velyhan, A. [Institute of Physics, ASCR, v.v.i., 182 21 Prague 8 (Czech Republic); Kravarik, J. [Institute of Physics, ASCR, v.v.i., 182 21 Prague 8 (Czech Republic); Czech Technical University, Faculty of Electro-Engineering, Prague (Czech Republic); Ullschmied, J. [Institute of Physics, ASCR, v.v.i., 182 21 Prague 8 (Czech Republic); Wolowski, J.; Szydlowski, A.; Rosinski, M. [Institute of Plasma Physics and Laser Microfusion, IPPLM, 23 Hery Str., 01-497 Warsaw (Poland)

    2013-05-01

    A 10{sup 16} W/cm{sup 2} Asterix laser pulse intensity, 1315 nm wavelength, 300 ps pulse duration, was employed at PALS laboratory of Prague, to irradiate thick and thin primary CD{sub 2} targets placed into the high vacuum chamber. The laser irradiation produces non-equilibrium plasma with deuterons and carbon ions emission with energy up to about 4 MeV per charge state, as measured by time-of-flight (TOF) techniques by using ion collectors and silicon carbide detectors. Accelerated deuterium ions may induce high D–D cross section for fusion processes generating 3 MeV protons and 2.5 MeV neutrons, as measured by TOF analyses. In order to increase the mono-energetic proton yield, secondary CD{sub 2} targets can be availed to be irradiated by the plasma-accelerated deuterons. Experiments demonstrated that high intensity laser pulses can be employed to promote nuclear reactions from which characteristic ion streams may be developed. Results open new scenario for applications of laser-generated plasma to the fields of ion sources and ion accelerators.

  18. Deuterium-deuterium nuclear reaction induced by high intensity laser pulses

    Science.gov (United States)

    Torrisi, L.; Cavallaro, S.; Cutroneo, M.; Giuffrida, L.; Krasa, J.; Margarone, D.; Velyhan, A.; Kravarik, J.; Ullschmied, J.; Wolowski, J.; Szydlowski, A.; Rosinski, M.

    2013-05-01

    A 1016 W/cm2 Asterix laser pulse intensity, 1315 nm wavelength, 300 ps pulse duration, was employed at PALS laboratory of Prague, to irradiate thick and thin primary CD2 targets placed into the high vacuum chamber. The laser irradiation produces non-equilibrium plasma with deuterons and carbon ions emission with energy up to about 4 MeV per charge state, as measured by time-of-flight (TOF) techniques by using ion collectors and silicon carbide detectors. Accelerated deuterium ions may induce high D-D cross section for fusion processes generating 3 MeV protons and 2.5 MeV neutrons, as measured by TOF analyses. In order to increase the mono-energetic proton yield, secondary CD2 targets can be availed to be irradiated by the plasma-accelerated deuterons. Experiments demonstrated that high intensity laser pulses can be employed to promote nuclear reactions from which characteristic ion streams may be developed. Results open new scenario for applications of laser-generated plasma to the fields of ion sources and ion accelerators.

  19. Pulsed Power Science and Technology: A Strategic Outlook for the National Nuclear Security Administration (Summary)

    Energy Technology Data Exchange (ETDEWEB)

    Sinars, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scott, Kimberly Carole [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Edwards, M. John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olson, Russell Teall [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-17

    Major advances in pulsed power technology and applications over the last twenty years have expanded the mission areas for pulsed power and created compelling new opportunities for the Stockpile Stewardship Program (SSP). This summary document is a forward look at the development of pulsed power science and technology (PPS&T) capabilities in support of the next 20 years of the SSP. This outlook was developed during a three-month-long tri-lab study on the future of PPS&T research and capabilities in support of applications to: (1) Dynamic Materials, (2) Thermonuclear Burn Physics and Inertial Confinement Fusion (ICF), and (3) Radiation Effects and Nuclear Survivability. It also considers necessary associated developments in next-generation codes and pulsed power technology as well as opportunities for academic, industry, and international engagement. The document identifies both imperatives and opportunities to address future SSP mission needs. This study was commissioned by the National Nuclear Security Administration (NNSA). A copy of the memo request is contained in the Appendix. NNSA guidance received during this study explicitly directed that it not be constrained by resource limitations and not attempt to prioritize its findings against plans and priorities in other areas of the national weapons program. That prioritization, including the relative balance amongst the three focus areas themselves, must of course occur before any action is taken on the observations presented herein. This unclassified summary document presents the principal imperatives and opportunities identified in each mission and supporting area during this study. Preceding this area-specific outlook, we discuss a cross-cutting opportunity to increase the shot capacity on the Z pulsed power facility as a near-term, cost-effective way to broadly impact PPS&T for SSP as well as advancing the science and technology to inform future SSMP milestones over the next 5-10 years. The final page of the

  20. Pulsed Power Science and Technology: A Strategic Outlook for the National Nuclear Security Administration (Summary)

    Energy Technology Data Exchange (ETDEWEB)

    Sinars, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scott, Kimberly Carole [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Edwards, M. John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olson, Russell Teall [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-17

    Major advances in pulsed power technology and applications over the last twenty years have expanded the mission areas for pulsed power and created compelling new opportunities for the Stockpile Stewardship Program (SSP). This summary document is a forward look at the development of pulsed power science and technology (PPS&T) capabilities in support of the next 20 years of the SSP. This outlook was developed during a three month long tri-lab study on the future of PPS&T research and capabilities in support of applications to: (1) Dynamic Materials, (2) Thermonuclear Burn Physics and Inertial Confinement Fusion (ICF), and (3) Radiation Effects and Nuclear Survivability. It also considers necessary associated developments in next-generation codes and pulsed power technology as well as opportunities for academic, industry, and international engagement. The document identifies both imperatives and opportunities to address future SSP mission needs. This study was commissioned by the National Nuclear Security Administration (NNSA). A copy of the memo request is contained in the Appendix. NNSA guidance received during this study explicitly directed that it not be constrained by resource limitations and not attempt to prioritize its findings against plans and priorities in other areas of the national weapons program. That prioritization, including the relative balance amongst the three focus areas themselves, must of course occur before any action is taken on the observations presented herein. This unclassified summary document presents the principal imperatives and opportunities identified in each mission and supporting area during this study. Proceeding this area-specific outlook, we discuss a cross-cutting opportunity to increase the shot capacity on the Z pulsed power facility as a near term, cost effective way to broadly impact PPS&T for SSP as well as advancing the science and technology to inform future SSMP milestones over the next 5-10 years. The final page of the

  1. Development of Nuclear Magnetic Resonance Pulse Sequences and Probes to Study Biomacromolecules

    Energy Technology Data Exchange (ETDEWEB)

    Cosman, M; Krishnan, V V; Maxwell, R

    2001-02-26

    The determination of the three dimensional structures at high resolution of biomolecules, such as proteins and nucleic acids, enables us to understand their function at the molecular level. At the present time, there are only two methods available for determining such structures, nuclear magnetic resonance (NMR) spectroscopy and X-ray diffraction. Compared to well-established X-ray diffraction techniques, NMR methodology is relatively new and has many areas in which improvement can still be attained. In this project, we focused on the development of new NMR probes and pulse sequences that were tailored to tackle specific problems that are not adequately addressed by current technology. Probes are the hardware that contain the radio frequency (RF) circuitry used to both excite and detect the NMR signals. Pulse sequences are composed of a series of RF pulses and delays, which are applied to the sample held within the magnetic field by the probe, so as to manipulate the nuclear spins. Typically, a probe is developed for a specific set of nuclei and types of experiments and the pulse sequences are then written to use the probe in an optimal manner. In addition, the inter-development of instrumentation and methods are determined by the specific biological question to be examined. Thus our efforts focused on addressing an area of importance in NMR Structural Biology namely more effective ways to use the phosphorus ({sup 31}P) nucleus. Phosphorus is a very important biological element that is strategically located in nucleic acids, where it imparts negative charge and flexibility to RNA and DNA. It is also a component of the cellular membrane and thus interacts with membrane proteins. It is used in mechanisms to signal, activate or deactivate enzymes; and participates in energy storage and release. However, the phosphorus nucleus exhibits certain properties, such as poor spectral dispersion, low sensitivity of detection, and fast relaxation, which limit its effective use

  2. Effects of combined treatment with ibandronate and pulsed electromagnetic field on ovariectomy-induced osteoporosis in rats.

    Science.gov (United States)

    Zhou, Jun; Liao, Yuan; Xie, Haitao; Liao, Ying; Zeng, Yahua; Li, Neng; Sun, Guanghua; Wu, Qi; Zhou, Guijuan

    2017-01-01

    Ibandronate (IBN) and pulsed electromagnetic field (PEMF) have each shown positive effects for treating osteoporosis, but no study has evaluated the relative effects of these treatments combined. This study investigated the effects of IBN + PEMF on bone turnover, mineral density, microarchitecture, and biomechanical properties in an ovariectomized (OVX) rat model of osteoporosis. Fifty 3-month-old rats were randomly apportioned to receive a sham-operation (n = 10), or ovariectomy (n = 40). The latter group was equally divided as the model (OVX control) or to receive IBN, PEMF, or IBN + PEMF. Beginning the day after surgery, the IBN and IBN + PEMF groups received weekly subcutaneous IBN; the PEMF and IBN + PEMF groups were given daily PEMF during the same 12 weeks. After 12 weeks of treatments, biochemical parameters, bone mineral density (BMD), microarchitecture parameters, biomechanical properties, and some metabolic modulators that are involved in bone resorption were compared. The L5 lumbar vertebral body BMDs of the IBN, PEMF, and IBN + PEMF groups were 121.6%, 119.5%, and 139.6%; maximum loads were 111.4%, 112.7%, and 121.9%; and energy to failure was 130.8%, 129.2%, and 154.9% of the OVX model, respectively. The IBN + PEMF group had significantly lower levels of serum tartrate-resistant acid phosphatase 5b, and greater improvement in BMD, bone microarchitecture, and strength of the lumbar spine compared with monotherapy groups. Results showed that IBN + PEMF had a more favorable effect on the lumbar spine in this osteoporosis model than did either monotherapy. Bioelectromagnetics. 38:31-40, 2017. © 2016 Wiley Periodicals, Inc.

  3. Pulsed electromagnetic field therapy for management of osteoarthritis-related pain, stiffness and physical function: clinical experience in the elderly.

    Science.gov (United States)

    Iannitti, Tommaso; Fistetto, Gregorio; Esposito, Anna; Rottigni, Valentina; Palmieri, Beniamino

    2013-01-01

    Pulsed electromagnetic field (PEMF) therapy has shown promising therapeutic effectiveness on bone- and cartilage-related pathologies, being also safe for management of knee osteoarthritis. The aim of this study was to investigate the clinical efficacy of a PEMF device for management of knee osteoarthritis in elderly patients. A total of 33 patients were screened, and 28 patients, aged between 60 and 83 and affected by bilateral knee osteoarthritis, were enrolled in this study. They received PEMF therapy on the right leg for a total of three 30-minute sessions per week for a period of 6 weeks, while the left leg did not receive any treatment and served as control. An intravenous drip containing ketoprofen, sodium clodronate, glucosamine sulfate, calcitonin, and ascorbic acid, for a total volume of 500 mL, was administered during PEMF therapy. At baseline and 3 months post-PEMF therapy, Visual Analog Scale (VAS) was used to assess knee pain and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) was used to measure knee pain, stiffness and physical function. Changes in VAS and WOMAC scores were calculated for both knees as baseline minus post-treatment. A two sample Student's t-test, comparing change in knee-related VAS pain for PEMF-treated leg (49.8 ± 2.03) vs control leg (11 ± 1.1), showed a significant difference in favor of PEMF therapy (P physical function for PEMF-treated leg (8.5 ± 0.4, 3.5 ± 0.2, 38.5 ± 2.08, respectively) vs control leg (2.6 ± 0.2; 1.6 ± 0.1; 4.5 ± 0.5 respectively), also showed a significant difference in favor of PEMF therapy (P therapy were observed. The present study shows that PEMF therapy improves pain, stiffness and physical function in elderly patients affected by knee osteoarthritis.

  4. Comparative study of the efficacy of pulsed electromagnetic field and low level laser therapy on mitogen-activated protein kinases

    Directory of Open Access Journals (Sweden)

    Ayman M. El-Makakey

    2017-03-01

    Full Text Available Mitogen-Activated Protein Kinases (MAPKs consist of three major signaling members: extracellular signal-regulated kinase (ERK, p38 and C-JUN N-terminal kinase (JNK. We investigated physiological effects of Pulsed Electromagnetic Field Therapy (PEMFT and Low Level Laser Therapy (LLLT on human body, adopting the expression level of mitogen-activated protein kinases as an indicator via assessment of the activation levels of three major families of MAPKS, ERK, p38 and JNK in the peripheral lymphocytes of patients before and after the therapies. Assessment for the expression levels of MAPKs families' were done, in the peripheral lymphocytes of patients recently have appendectomy, using flow cytometric analysis of multiple signaling pathways, pre and post LLLT and PEMFT application (twice daily for 6 successive days on the appendectomy wound. There were non-significant differences in the expression levels of MAPKs families' pre- therapies application. But there were significant increase in the ERK expression levels post application of LLLT compared to its pre application (p<0.01. Also, there was significant increase in the ERK, p38 and C-Jun N terminal expression level values post application of PEMFT compared to its pre application expression levels (p<0.01 for each. The present study demonstrates that PEMFT has a powerful healing effect more than LLLT as it increase the activation of ERK, P38 and C-Jun-N Terminal while LLLT only increase the activation of ERK. LLLT has more potent pain decreasing effect than PEMFT as it does not activate P38 pathway like PEMFT.

  5. Mechanical stimulation (pulsed electromagnetic fields "PEMF" and extracorporeal shock wave therapy "ESWT" and tendon regeneration: a possible alternative.

    Directory of Open Access Journals (Sweden)

    Federica eRosso

    2015-11-01

    Full Text Available The pathogenesis of tendon degeneration and tendinopathy is still partially unclear. However, an active role of metalloproteinases (MMP, growth factors, such as vascular endothelial growth factor (VEGF and a crucial role of inflammatory elements and cytokines was demonstrated. Mechanical stimulation may play a role in regulation of inflammation. In vitro studies demonstrated that both pulsed electromagnetic fields (PEMF and extracorporeal shock wave therapy (ESWT increased the expression of pro-inflammatory cytokine such as interleukin (IL-6 and IL-10. Moreover ESWT increases the expression of growth factors, such as transforming growth factor beta (TGF-beta, Vascular Endothelial Growth Factor (VEGF, and insulin-like growth factor 1 (IGF1, as well as the synthesis of collagen I fibers. These pre-clinical results, in association with several clinical studies, suggest a potential effectiveness of ESWT for tendinopathy treatment. Recently PEMF gained popularity as adjuvant for fracture healing and bone regeneration. Similarly to ESWT, the mechanical stimulation obtained using PEMFs may play a role for treatment of tendinopathy and for tendon regeneration, increasing in-vitro TGF-beta production, as well as scleraxis and collagen I gene expression. In this manuscript the rational of mechanical stimulations and the clinical studies on the efficacy of extracorporeal shock wave (ESW and PEMF will be discussed. However, no clear evidence of a clinical value of ESW and PEMF has been found in literature with regards to the treatment of tendinopathy in human, so further clinical trials are needed to confirm the promising hypotheses concerning the effectiveness of ESWT and PEMF mechanical stimulation.

  6. [Effect of pulsed electromagnetic fields (PEMF) on human periodontal ligament in vitro. Alterations of intracellular Ca2+].

    Science.gov (United States)

    Satake, T; Yasu, N; Kakai, Y; Kawamura, T; Sato, T; Nakano, T; Amino, S; Ishiwata, Y; Saito, S

    1990-03-01

    The concept of orthodontic tooth movement is based on the hypothesis that teeth move as a result of the biological response of periodontal tissues to the mechanical forces applied. There is a widely held hypothesis that mechanical stress generates an electrical signal which sets in motion the subsequent events, as in bone exposed to mechanical forces electrical currents are produced affect bone growth and remodeling. This implies a transduction mechanism which translates the electrical signal into a biochemical message, recognizable by the cellular machine. This study is aimed at the identification of the message and the investigation of its control. In fact, the effect of Pulsed Electromagnetic Fields (PEMF) on the intracellular second messenger, cytoplasmic Ca2+ in Human Periodontal Ligament Fibroblasts (HPLF) was investigated. The resting intracellular ionized calcium concentration ([Ca+2]i) of HPLF cells was 232.7 +/- 25.0 nM, and with PEMF [Ca2+]i increased from 12 hrs to 499.0 +/- 115.5 nM up to 12 hrs, then reached to a steady level through 24 hrs. The PEMF were also found to decrease the responses towards epidermal growth factor (EGF) and serum, when the degree of response was based on the intracellular Ca2+ transient. These effects of PEMF were mimicked by 12-0-tetradecanoyl phorbol 13-acetate (TPA), a potent activator of protein kinase C. Some reports have suggested that fibroblasts of the periodontal ligament contain high alkaline phosphatase (ALPase) activity as much as osteoblast. Since similar results concerning the [Ca2+]i were obtained in osteoblast (OB)-like cells, this experiment also supports the hypothesis that fibroblasts of periodontal ligament have osteoblastic features.

  7. A study of the effects of flux density and frequency of pulsed electromagnetic field on neurite outgrowth in PC12 cells.

    Science.gov (United States)

    Zhang, Yang; Ding, Jun; Duan, Wei

    2006-01-01

    The aim of this study was to investigate the influence of pulsed electromagnetic fields with various flux densities and frequencies on neurite outgrowth in PC12 rat pheochromocytoma cells. We have studied the percentage of neurite-bearing cells, average length of neurites and directivity of neurite outgrowth in PC12 cells cultured for 96 hours in the presence of nerve growth factor (NGF). PC12 cells were exposed to 50 Hz pulsed electromagnetic fields with a flux density of 1.37 mT, 0.19 mT and 0.016 mT respectively. The field was generated through a Helmholtz coil pair housed in one incubator and the control samples were placed in another identical incubator. It was found that exposure to both a relatively high flux density (1.37 mT) and a medium flux density (0.19 mT) inhibited the percentage of neurite-bearing cells and promoted neurite length significantly. Exposure to high flux density (1.37 mT) also resulted in nearly 20% enhancement of neurite directivity along the field direction. However, exposure to low flux density field (0.016 mT) had no detectable effect on neurite outgrowth. We also studied the effect of frequency at the constant flux density of 1.37 mT. In the range from 1 approximately 100 Hz, only 50 and 70 Hz pulse frequencies had significant effects on neurite outgrowth. Our study has shown that neurite outgrowth in PC12 cells is sensitive to flux density and frequency of pulsed electromagnetic field.

  8. Electromagnetic launchers

    Science.gov (United States)

    Kolm, H.; Mongeau, P.; Williams, F.

    1980-09-01

    Recent advances in energy storage, switching and magnet technology make electromagnetic acceleration a viable alternative to chemical propulsion for certain tasks, and a means to perform other tasks not previously feasible. Applications include the acceleration of gram-size particles for hypervelocity research and the initiation of fusion by impact, a replacement for chemically propelled artillery, the transportation of cargo and personnel over inaccessible terrain, and the launching of space vehicles to supply massive space operations, and for the disposal of nuclear waste. The simplest launcher of interest is the railgun, in which a short-circuit slide or an arc is driven along two rails by direct current. The most sophisticated studied thus far is the mass driver, in which a superconducting shuttle bucket is accelerated by a line of pulse coils energized by capacitors at energy conversion efficiencies better than 90%. Other accelerators of interest include helical, brush-commutated motors, discrete coil arc commutated drivers, flux compression momentum transformers, and various hybrid electrochemical devices.

  9. The effect of external magnetic field on the density distributions and electromagnetic fields in the interaction of high-intensity short laser pulse with collisionless underdense plasma

    Science.gov (United States)

    Mahmoodi-Darian, Masoomeh; Ettehadi-Abari, Mehdi; Sedaghat, Mahsa

    2016-03-01

    Laser absorption in the interaction between ultra-intense femtosecond laser and solid density plasma is studied theoretically here in the intensity range I{λ^2} ˜eq 10^{14}{-}10^{16}{{W}}{{{cm}}^{-2}} \\upmu{{{m}}2} . The collisionless effect is found to be significant when the incident laser intensity is less than 10^{16}{{W}}{{{cm}}^{-2}}\\upmu{{{m}}2} . In the current work, the propagation of a high-frequency electromagnetic wave, for underdense collisionless plasma in the presence of an external magnetic field is investigated. When a constant magnetic field parallel to the laser pulse propagation direction is applied, the electrons rotate along the magnetic field lines and generate the electromagnetic part in the wake with a nonzero group velocity. Here, by considering the ponderomotive force in attendance of the external magnetic field and assuming the isothermal collisionless plasma, the nonlinear permittivity of the plasma medium is obtained and the equation of electromagnetic wave propagation in plasma is solved. Here, by considering the effect of the ponderomotive force in isothermal collisionless magnetized plasma, it is shown that by increasing the laser pulse intensity, the electrons density profile leads to steepening and the electron bunches of plasma become narrower. Moreover, it is found that the wavelength of electric and magnetic field oscillations increases by increasing the external magnetic field and the density distribution of electrons also grows in comparison to the unmagnetized collisionless plasma.

  10. Scintillation-only Based Pulse Shape Discrimination for Nuclear and Electron Recoils in Liquid Xenon

    CERN Document Server

    Ueshima, K; Hiraide, K; Hirano, S; Kishimoto, Y; Kobayashi, K; Koshio, Y; Liu, J; Martens, K; Moriyama, S; Nakahata, M; Nishiie, H; Ogawa, H; Sekiya, H; Shinozaki, A; Suzuki, Y; Takeda, A; Yamashita, M; Fujii, K; Murayama, I; Nakamura, S; Otsuka, K; Takeuchi, Y; Fukuda, Y; Nishijima, K; Motoki, D; Itow, Y; Masuda, K; Nishitani, Y; Uchida, H; Tasaka, S; Ohsumi, H; Kim, Y D; Kim, Y H; Lee, K B; Lee, M K

    2011-01-01

    In a dedicated test setup at the Kamioka Observatory we studied pulse shape discrimination (PSD) in liquid xenon (LXe) for dark matter searches. PSD in LXe was based on the observation that scintillation light from electron events was emitted over a longer period of time than that of nuclear recoil events, and our method used a simple ratio of early to total scintillation light emission in a single scintillation event. Requiring an efficiency of 50% for nuclear recoil retention we reduced the electron background to 7.7\\pm1.1(stat)\\pm1.2 0.6(sys)\\times10-2 at energies between 4.8 and 7.2 keVee and to 7.7\\pm2.8(stat)\\pm2.5 2.8(sys)\\times10-3 at energies between 9.6 and 12 keVee for a scintillation light yield of 20.9 p.e./keV. Further study was done by masking some of that light to reduce this yield to 4.6 p.e./keV, the same method results in an electron event reduction of 2.4\\pm0.2(stat)\\pm0.3 0.2(sys)\\times10-1 for the lower of the energy regions above. We also observe that in contrast to nuclear recoils the ...

  11. Measurement of Scintillation and Ionization Yield and Scintillation Pulse Shape from Nuclear Recoils in Liquid Argon

    CERN Document Server

    Cao, H; Avetisyan, R; Back, H O; Cocco, A G; DeJongh, F; Fiorillo, G; Galbiati, C; Grandi, L; Guardincerri, Y; Kendziora, C; Lippincott, W H; Love, C; Lyons, S; Manenti, L; Martoff, C J; Meng, Y; Montanari, D; Mosteiro, P; Olvitt, D; Pordes, S; Qian, H; Rossi, B; Saldanha, R; Sangiorgio, S; Siegl, K; Strauss, S Y; Tan, W; Tatarowicz, J; Walker, S; Wang, H; Watson, A W; Westerdale, S; Yoo, J

    2014-01-01

    We have measured the scintillation and ionization yield of recoiling nuclei in liquid argon as a function of applied electric field by exposing a dual-phase Liquid Argon Time Projection Chamber (LAr-TPC) to a low energy pulsed narrowband neutron beam produced at the Notre Dame Institute for Structure and Nuclear Astrophysics. Liquid scintillation counters were arranged to detect and identify neutrons scattered in the TPC and to select the energy of the recoiling nuclei. We report measurements of the scintillation and ionization yields for nuclear recoils with energies from 10.3 to 57.2 keV and for applied electric fields from 0 to 1000 V/cm. We also report the observation of an anti-correlation between scintillation and ionization from nuclear recoils, which is similar to the anti-correlation between scintillation and ionization from electron recoils. A comparison of the light and charge yield of recoils parallel and perpendicular to the applied electric field yielded a first evidence of sensitivity to direct...

  12. Measurement of scintillation and ionization yield and scintillation pulse shape from nuclear recoils in liquid argon

    Energy Technology Data Exchange (ETDEWEB)

    Cao, H.; Alexander, T.; Aprahamian, A.; Avetisyan, R.; Back, H. O.; Cocco, A. G.; DeJongh, F.; Fiorillo, G.; Galbiati, C.; Grandi, L.; Guardincerri, Y.; Kendziora, C.; Lippincott, W. H.; Love, C.; Lyons, S.; Manenti, L.; Martoff, C. J.; Meng, Y.; Montanari, D.; Mosteiro, P.; Olvitt, D.; Pordes, S.; Qian, H.; Rossi, B.; Saldanha, R.; Sangiorgio, S.; Siegl, K.; Strauss, S. Y.; Tan, W.; Tatarowicz, J.; Walker, S.; Wang, H.; Watson, A. W.; Westerdale, S.; Yoo, J.

    2015-05-01

    We have measured the scintillation and ionization yield of recoiling nuclei in liquid argon as a function of applied electric field by exposing a dual-phase liquid argon time projection chamber (LAr-TPC) to a low energy pulsed narrow band neutron beam produced at the Notre Dame Institute for Structure and Nuclear Astrophysics. Liquid scintillation counters were arranged to detect and identify neutrons scattered in the TPC and to select the energy of the recoiling nuclei. We report measurements of the scintillation yields for nuclear recoils with energies from 10.3 to 57.3 keV and for median applied electric fields from 0 to 970 V / cm . For the ionization yields, we report measurements from 16.9 to 57.3 keV and for electric fields from 96.4 to 486 V / cm . We also report the observation of an anticorrelation between scintillation and ionization from nuclear recoils, which is similar to the anticorrelation between scintillation and ionization from electron recoils. Assuming that the energy loss partitions into excitons and ion pairs from 83 m Kr internal conversion electrons is comparable to that from 207 Bi conversion electrons, we obtained the numbers of excitons ( N ex ) and ion pairs ( N i ) and their ratio ( N ex / N i ) produced by nuclear recoils from 16.9 to 57.3 keV. Motivated by arguments suggesting direction sensitivity in LAr-TPC signals due to columnar recombination, a comparison of the light and charge yield of recoils parallel and perpendicular to the applied electric field is presented for the first time.

  13. Laser spectroscopy of atoms in superfluid helium for the measurement of nuclear spins and electromagnetic moments of radioactive atoms

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, T., E-mail: tomomi.fujita@riken.jp [Osaka University, Department of Physics (Japan); Furukawa, T. [Tokyo Metropolitan University, Department of Physics (Japan); Imamura, K.; Yang, X. F. [RIKEN Nishina Center (Japan); Hatakeyama, A. [Tokyo University of Agriculture and Technology, Department of Applied Physics (Japan); Kobayashi, T. [RIKEN Center for Advanced Photonics (Japan); Ueno, H. [RIKEN Nishina Center (Japan); Asahi, K. [Tokyo Institute of Technology, Department of Physics (Japan); Shimoda, T. [Osaka University, Department of Physics (Japan); Matsuo, Y. [Hosei University, Department of Advanced Sciences (Japan); Collaboration: OROCHI Collaboration

    2015-11-15

    A new laser spectroscopic method named “OROCHI (Optical RI-atom Observation in Condensed Helium as Ion catcher)” has been developed for deriving the nuclear spins and electromagnetic moments of low-yield exotic nuclei. In this method, we observe atomic Zeeman and hyperfine structures using laser-radio-frequency/microwave double-resonance spectroscopy. In our previous works, double-resonance spectroscopy was performed successfully with laser-sputtered stable atoms including non-alkali Au atoms as well as alkali Rb and Cs atoms. Following these works, measurements with {sup 84−87}Rb energetic ion beams were carried out in the RIKEN projectile fragment separator (RIPS). In this paper, we report the present status of OROCHI and discuss its feasibility, especially for low-yield nuclei such as unstable Au isotopes.

  14. Detection of accelerated particles from pulsed plasma discharge using solid state nuclear track detector

    Indian Academy of Sciences (India)

    G M El-Aragi; U Seddik; A Abd El-Haliem

    2007-04-01

    The ion beam of a Mather-type 23.25 J plasma focus device operated with air filling at 10 Torr was registered using CR-39 nuclear track detector. The irradiated samples were etched in NaOH solution at 70°C for 1 h. It is found here that plasma beam contains multi-components of microbeams. The individual track density of microbeams is estimated and the total current density of the plasma stream is measured to be 1.2 mA/cm2. A model for counting the track density of individual microbeams is proposed here. Faraday cup measurements showed the ion pulse with energy ranging from 5.8 keV to 3.3 keV.

  15. The Determination of Deuterium and Tritium in Effluent Wastewater by Pulsed Nuclear Magnetic Resonance Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Attalla, A.; Birkbeck, J. C.

    1985-04-01

    A pulsed nuclear magnetic resonance (NMR) procedure was developed for the quantitative determination of deuterium and tritium in radioactive, effluent, wastewater to aid in the design of an efficient combined electrolytic/catalytic exchange system for the recovery of these hydrogen isotopes. The deuterium and tritium NMR signals were observed at 9.210 and 45.7 MHz, respectively. Ten different effluent water samples were analyzed for deuterium and tritium to establish base-line data for the preparation of standard reference samples. The hydrogen isotope concentrations ranged from 0.11 to 2.40 g deuterium and from 2.0 to 21.0 mg tritium per liter of processed sample. The standard deviation of the hydrogen isotope determinations is +- 0.017 g deuterium and +- 0.06 mg tritium per liter of processed effluent water. In the future, the effectiveness of specially prepared and analyzed (calorimetry) effluent samples as tritium standards will be investigated.

  16. Pulsed electromagnetic fields partially preserve bone mass, microarchitecture, and strength by promoting bone formation in hindlimb-suspended rats.

    Science.gov (United States)

    Jing, Da; Cai, Jing; Wu, Yan; Shen, Guanghao; Li, Feijiang; Xu, Qiaoling; Xie, Kangning; Tang, Chi; Liu, Juan; Guo, Wei; Wu, Xiaoming; Jiang, Maogang; Luo, Erping

    2014-10-01

    A large body of evidence indicates that pulsed electromagnetic fields (PEMF), as a safe and noninvasive method, could promote in vivo and in vitro osteogenesis. Thus far, the effects and underlying mechanisms of PEMF on disuse osteopenia and/or osteoporosis remain poorly understood. Herein, the efficiency of PEMF on osteoporotic bone microarchitecture, bone strength, and bone metabolism, together with its associated signaling pathway mechanism, was systematically investigated in hindlimb-unloaded (HU) rats. Thirty young mature (3-month-old), male Sprague-Dawley rats were equally assigned to control, HU, and HU + PEMF groups. The HU + PEMF group was subjected to daily 2-hour PEMF exposure at 15 Hz, 2.4 mT. After 4 weeks, micro-computed tomography (µCT) results showed that PEMF ameliorated the deterioration of trabecular and cortical bone microarchitecture. Three-point bending test showed that PEMF mitigated HU-induced reduction in femoral mechanical properties, including maximum load, stiffness, and elastic modulus. Moreover, PEMF increased serum bone formation markers, including osteocalcin (OC) and N-terminal propeptide of type 1 procollagen (P1NP); nevertheless, PEMF exerted minor inhibitory effects on bone resorption markers, including C-terminal crosslinked telopeptides of type I collagen (CTX-I) and tartrate-resistant acid phosphatase 5b (TRAcP5b). Bone histomorphometric analysis demonstrated that PEMF increased mineral apposition rate, bone formation rate, and osteoblast numbers in cancellous bone, but PEMF caused no obvious changes on osteoclast numbers. Real-time PCR showed that PEMF promoted tibial gene expressions of Wnt1, LRP5, β-catenin, OPG, and OC, but did not alter RANKL, RANK, or Sost mRNA levels. Moreover, the inhibitory effects of PEMF on disuse-induced osteopenia were further confirmed in 8-month-old mature adult HU rats. Together, these results demonstrate that PEMF alleviated disuse-induced bone loss by promoting skeletal anabolic activities

  17. High-speed nuclear quality pulse height analyzer for synchrotron-based applications

    Energy Technology Data Exchange (ETDEWEB)

    Beche, Jean-Francois; Bucher, Jerome J.; Fabris, Lorenzo; Riot, Vincent J.

    2001-04-01

    A high throughput Pulse Height Analyzer system for synchrotron-based applications requiring high resolution, high processing speed and low dead time has been developed. The system is comprised of a 120ns 12-bit nuclear quality Analog to Digital converter with a self-adaptive fast peak detector-stretcher and a custom-made fast histogramming memory module that records and processes the digitized data. The histogramming module is packaged in a VME or VXI compatible interface. Data is transferred through a fast optical link from the memory interface to a computer. A dedicated data acquisition program matches the hardware characteristics of the histogramming memory module. The data acquisition system allows for two data collection modes: ''standard'' data acquisition mode where the data is accumulated and read in synchronization with an external trigger and ''live'' data acquisition mode where the system operates as a standard Pulse Height Analyzer. The acquisition, standard or live, can be performed on several channels simultaneously. A two-channel prototype has been demonstrated at the Stanford Synchrotron Radiation Laboratory accelerator in conjunction with an X-ray Fluorescence Absorption Spectroscopy experiment. A detailed description of the entire system is given and experimental data is shown.

  18. Effects of nuclear weapons. Third edition

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, S.; Dolan, P.J.

    1977-01-01

    Since the last edition of ''The Effects of Nuclear Weapons'' in 1962 much new information has become available concerning nuclear weapon effects. This has come in part from the series of atmospheric tests, including several at very high altitudes, conducted in the Pacific Ocean area in 1962. In addition, laboratory studies, theoretical calculations, and computer simulations have provided a better understanding of the various effects. A new chapter has been added on the electromagnetic pulse. The chapter titles are as follows: general principles of nuclear explosions; descriptions of nuclear explosions; air blast phenomena in air and surface bursts; air blast loading; structural damage from air blast; shock effects of surface and subsurface bursts; thermal radiation and its effects; initial nuclear radiation; residual nuclear radiation and fallout; radio and radar effects; the electromagnetic pulse and its effects; and biological effects. (LTN)

  19. The Effects of Nuclear Weapons. Third edition

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, S; Dolan, P J

    1977-01-01

    Since the last edition of ''The Effects of Nuclear Weapons'' in 1962 much new information has become available concerning nuclear weapon effects. This has come in part from the series of atmospheric tests, including several at very high altitudes, conducted in the Pacific Ocean area in 1962. In addition, laboratory studies, theoretical calculations, and computer simulations have provided a better understanding of the various effects. A new chapter has been added on the electromagnetic pulse. The chapter titles are as follows: general principles of nuclear explosions; descriptions of nuclear explosions; air blast phenomena in air and surface bursts; air blast loading; structural damage from air blast; shock effects of surface and subsurface bursts; thermal radiation and its effects; initial nuclear radiation; residual nuclear radiation and fallout; radio and radar effects; the electromagnetic pulse and its effects; and biological effects. (LTN)

  20. Electromagnetic and Weak Nuclear Structure Functions $F_{1,2}(x,Q^2)$ in the Intermediate Region of $Q^2$

    CERN Document Server

    Haider, H; Athar, M Sajjad; Singh, S K; Simo, I Ruiz

    2016-01-01

    We have studied nuclear structure functions $F_{1A}(x,Q^2)$ and $F_{2A}(x,Q^2)$ for electromagnetic and weak processes in the region of $1 GeV^2 < Q^2 <8 GeV^2$. The nuclear medium effects arising due to Fermi motion, binding energy, nucleon correlations, mesonic contributions and shadowing effects are taken into account using a many body field theoretical approach. The calculations are performed in a local density approximation using a relativistic nucleon spectral function. The results are compared with the available experimental data. Implications of nuclear medium effects on the validity of Callan-Gross relation are also discussed.

  1. Scintillation-only based pulse shape discrimination for nuclear and electron recoils in liquid xenon

    Energy Technology Data Exchange (ETDEWEB)

    Ueshima, K., E-mail: ueshima@suketto.icrr.u-tokyo.ac.jp [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Abe, K.; Hiraide, K.; Hirano, S. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Kishimoto, Y. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Kobayashi, K.; Koshio, Y. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Liu, J.; Martens, K. [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Moriyama, S.; Nakahata, M. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Nishiie, H.; Ogawa, H.; Sekiya, H.; Shinozaki, A. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Suzuki, Y. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Takeda, A. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Yamashita, M. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Hida, Gifu 506-1205 (Japan); Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); and others

    2011-12-11

    In a dedicated test setup at the Kamioka Observatory we studied pulse shape discrimination (PSD) in liquid xenon (LXe) for dark matter searches in the absence of an externally applied electric field. PSD in LXe was based on the observation that scintillation light from electron events was emitted over a longer period of time than that of nuclear recoil events, and our method used a simple ratio of early to total scintillation light emission in a single scintillation event. Requiring an efficiency of 50% for nuclear recoil retention we reduced the electron background by a factor of 7.7{+-}1.1(stat){+-}{sub 0.6}{sup 1.2}(sys) Multiplication-Sign 10{sup -2} at energies between 4.8 and 7.2 keV{sub ee} and 7.7{+-}2.8(stat){+-}{sub 2.8}{sup 2.5}(sys) Multiplication-Sign 10{sup -3} at energies between 9.6 and 12 keV{sub ee} for a scintillation light yield of 20.9 photoelectrons/keV{sub ee}. Further study was done by masking some of that light to reduce this yield to 4.6 photoelectrons/keV{sub ee}. Under these conditions the same method results in an electron event reduction by a factor of 2.4{+-}0.2(stat){+-}{sub 0.2}{sup 0.3}(sys) Multiplication-Sign 10{sup -1} for the lower of the energy regions above. We also observe that in contrast to nuclear recoils the fluctuations in our early to total ratio for electron events are larger than expected from statistical fluctuations.

  2. Direct current superconducting quantum interference device spectrometer for pulsed nuclear magnetic resonance and nuclear quadrupole resonance at frequencies up to 5 MHz

    Science.gov (United States)

    TonThat, Dinh M.; Clarke, John

    1996-08-01

    A spectrometer based on a dc superconducting quantum interference device (SQUID) has been developed for the direct detection of nuclear magnetic resonance (NMR) or nuclear quadrupole resonance (NQR) at frequencies up to 5 MHz. The sample is coupled to the input coil of the niobium-based SQUID via a nonresonant superconducting circuit. The flux locked loop involves the direct offset integration technique with additional positive feedback in which the output of the SQUID is coupled directly to a low-noise preamplifier. Precession of the nuclear quadrupole spins is induced by a magnetic field pulse with the feedback circuit disabled; subsequently, flux locked operation is restored and the SQUID amplifies the signal produced by the nuclear free induction signal. The spectrometer has been used to detect 27Al NQR signals in ruby (Al2O3[Cr3+]) at 359 and 714 kHz.

  3. Effects of pulsed electromagnetic field on osteogenic and osteoclastic metabolism%脉冲电磁场对成骨和破骨代谢的影响

    Institute of Scientific and Technical Information of China (English)

    朱晓璐; 陈鹏; 田京

    2012-01-01

    BACKGROUND: The pulsed electromagnetic field can influence the osteoblast, osteoclast, and the bone matrix synthesis.OBJECTIVE: To explore the mechanism of the pulsed electromagnetic field for treatment of osteoporosis in order to promote its clinical application.METHODS: A computer-based online search of PubMed database, CNKI database, VIP database and Wanfang database from May 1997 to August 2011 was performed to search related articles with the key words of “pulsed electromagnetic fields (PEMFs),bone metabolism, osteoporosis, osteoblast, osteoclast, bone marrow mesenchymal stem cells (BMSCs)” in English and in Chinese by screening titles and abstracts. Articles related to pulsed electromagnetic field were selected. The documents published recently or in authoritative journals in the same field were preferred.RESULTS AND CONCLUSION: A total of 389 literatures were obtained in initial retrieval, and 46 documents of them concerning the analysis and treatment of aseptic loosening of aseptic prosthesis were involved to summarize according to inclusion criteria.PEMFs can promote osteogenic metabolism, inhibit osteoclastic metabolism, regulate transforming growth factor and Interleukin 6, promote bone matrix synthesis, improve the micro -environment for bone growth, as well as facilitate proliferation and differentiation of BMSCs. PEMFs have an important clinical value of treatment for osteoporosis and its complications.%背景:脉冲电磁场对成骨细胞、破骨细胞、骨基质合成均有明显作用.目的:旨在探究脉冲电磁场在成骨和破骨代谢中的作用以及治疗骨质疏松的机制,以促进其临床应用.关键词中以"pulsed electromagnetic field(PEMFs),bone metabolism,osteoporosis,osteoblast,osteoclast,bone marrow mesenchymal stem cells(BMMSCs)"或"脉冲电磁场,骨代谢,骨质疏松,成骨细胞,破骨细胞,骨髓间充质干细胞"为检索词进行检索.选择文章内容与脉冲电磁场有关者,同一领域文献则选

  4. Design of Pulse Circuit of Exciting Electromagnetic Ultrasonic%电磁超声脉冲激励电路的设计

    Institute of Scientific and Technical Information of China (English)

    胡力; 严仍春

    2013-01-01

    为了解决电磁超声能量转化效率较低、信号微弱的问题,设计了一种电磁超声脉冲激励电路.过零检测电路和单片机实现磁场强度与涡流激发的同步以及脉冲个数的控制;UCC3895芯片产生全桥电路的驱动信号,控制脉冲的频率和占空比;MOSFET管IRFP450构成全桥电路实现信号的功率放大.试验结果表明:该系统的稳定性好,可调节磁场强度,能有效地提高电磁超声能量转化效率.%A method of exciting electrical pulse for electromagnetic ultrasonic has been proposed which was to solve the key problems exist in electromagnetic ultrasonic test, such as low transduction efficiency and weak signal. Synchronization of magnetic field strength and eddy current excitation and the number of pulses were controlled by zero crossing detection circuit and MCU. A drive signal of the full bridge circuit was generated by UCC3895 chip to control the frequency and duty radio of the signal. Power amplification was realized by the full bridge constitute of IRFP450. The experimental results showed that the system had good stability, the magnetic field strength was adjustabled, and the electromagnetic ultrasonic energy conversion efficiency could be effectively improved.

  5. A novel non-linear recursive filter design for extracting high rate pulse features in nuclear medicine imaging and spectroscopy.

    Science.gov (United States)

    Sajedi, Salar; Kamal Asl, Alireza; Ay, Mohammad R; Farahani, Mohammad H; Rahmim, Arman

    2013-06-01

    Applications in imaging and spectroscopy rely on pulse processing methods for appropriate data generation. Often, the particular method utilized does not highly impact data quality, whereas in some scenarios, such as in the presence of high count rates or high frequency pulses, this issue merits extra consideration. In the present study, a new approach for pulse processing in nuclear medicine imaging and spectroscopy is introduced and evaluated. The new non-linear recursive filter (NLRF) performs nonlinear processing of the input signal and extracts the main pulse characteristics, having the powerful ability to recover pulses that would ordinarily result in pulse pile-up. The filter design defines sampling frequencies lower than the Nyquist frequency. In the literature, for systems involving NaI(Tl) detectors and photomultiplier tubes (PMTs), with a signal bandwidth considered as 15 MHz, the sampling frequency should be at least 30 MHz (the Nyquist rate), whereas in the present work, a sampling rate of 3.3 MHz was shown to yield very promising results. This was obtained by exploiting the known shape feature instead of utilizing a general sampling algorithm. The simulation and experimental results show that the proposed filter enhances count rates in spectroscopy. With this filter, the system behaves almost identically as a general pulse detection system with a dead time considerably reduced to the new sampling time (300 ns). Furthermore, because of its unique feature for determining exact event times, the method could prove very useful in time-of-flight PET imaging.

  6. Electromagnetic Structure of A=2 and 3 Nuclei and the Nuclear Current Operator

    Energy Technology Data Exchange (ETDEWEB)

    Rocco Schiavilla

    2005-02-01

    Different models for conserved two- and three-body electromagnetic currents are constructed from two- and three-nucleon interactions, using either meson-exchange mechanisms or minimal substitution in the momentum dependence of these interactions. The connection between these two different schemes is elucidated. A number of low-energy electronuclear observables, including (i) np radiative capture at thermal neutron energies and deuteron photodisintegration at low energies, (ii) nd and pd radiative capture reactions, and (iii) isoscalar and isovector magnetic form factors of {sup 3}H and {sup 3}He, are calculated in order to make a comparative study of these models for the current operator. The realistic Argonne v{sub 18} two-nucleon and Urbana IX or Tucson-Melbourne three-nucleon interactions are taken as a case study. For A=3 processes, the bound and continuum wave functions, both below and above deuteron breakup threshold, are obtained with the correlated hyperspherical-harmonics method. Three-body currents give small but significant contributions to some of the polarization observables in the {sup 2}H(p,{gamma}){sup 3}He process and the {sup 2}H(n,{gamma}){sup 3}H cross section at thermal neutron energies. It is shown that the use of a current which did not exactly satisfy current conservation with the two- and three-nucleon interactions in the Hamiltonian was responsible for some of the discrepancies reported in previous studies between the experimental and theoretical polarization observables in pd radiative capture.

  7. Development of the Bactericidal Treatment Room with High Electromagnetic Pulse Field%电磁脉冲高场强杀菌处理室的研制

    Institute of Scientific and Technical Information of China (English)

    解效白; 陈炜峰

    2012-01-01

    The pulsed electric field sterilization (Pulsed Electric Field,PEF) technology is a promising nonthermal sterilization science. The processing chamber which is the key component of the PEF directly influences the bactericidal effect. According to the principle of transmission line characteristic, the paper designed a coaxial processing chamber with impedance of 75 ohms and field strength of 50 kV/cm, and the treatment room was used to do the bactericidal test. The results showed that the processing chamber and the electromagnetic pulse source are well matched, the association of sterilization rate of the pulse peak voltage and irradiation pulse number is large,which can be used in the pilot study of the bactericidal mechanism.%脉冲电场杀菌技术是一项极具前景的食品非热杀菌技术,其处理关键部件——处理室直接影响杀菌效果.根据传输线原理,设计了特性阻抗为75Ω,场强可达到50kV/cm的同轴式处理室,并利用该处理室进行了杀菌试验.结果表明,处理室与电磁脉冲源匹配良好,杀菌率与脉冲峰值电压以及照射脉冲个数的关联度较大,可以用于杀菌机理的试验研究.

  8. Pulse-shape discrimination between electron and nuclear recoils in a NaI(Tl) crystal

    CERN Document Server

    Lee, H S; Adhikari, P; Choi, S; Hahn, I S; Jeon, E J; Joo, H W; Kang, W G; Kim, G B; Kim, H J; Kim, H O; Kim, K W; Kim, N Y; Kim, S K; Kim, Y D; Kim, Y H; Lee, J H; Lee, M H; Leonard, D S; Li, J; Oh, S Y; Olsen, S L; Park, H K; Park, H S; Park, K S; Shim, J H; So, J H

    2015-01-01

    We report on the response of a high light-output NaI(Tl) crystal to nuclear recoils induced by neutrons from an Am-Be source and compare the results with the response to electron recoils produced by Compton scattered 662 keV $\\gamma$-rays from a $^{137}$Cs source. The measured pulse-shape discrimination (PSD) power of the NaI(Tl) crystal is found to be significantly improved because of the high light output of the NaI(Tl) detector. We quantify the PSD power with a quality factor and estimate the sensitivity to the interaction rate for weakly interacting massive particles (WIMPs) with nucleons, and the result is compared with the annual modulation amplitude observed by the DAMA/LIBRA experiment. The sensitivity to spin-independent WIMP-nucleon interactions based on 100 kg$\\cdot$year of data from NaI detectors is estimated with simulated experiments, using the standard halo model.

  9. Pulsed Field Gradient Nuclear Magnetic Resonance and Applications in Yttrium Type Zeolites

    Science.gov (United States)

    Wu, Shaoxiong

    Molecular self-diffusion measurements by Pulsed Field Gradient Nuclear Magnetic Resonance (PFG NMR) spectroscopy can be applied to numerous fields. PFG NMR spectroscopy usually requires no special labeling for measuring hydrocarbon self-diffusion in a variety of samples. This is a significant advantage over using radioactive isotopes or photolabeled molecules since no special sample preparation or handling is required. A single set of experiments can yield diffusion coefficients and often can be performed in a few hours. The range of diffusion coefficients (10^{ -4} cm^2/s-10 ^{-10} cm^2/s) which can be determined by PFG NMR covers most ranges of molecular diffusion. This work describes the design of a PFG NMR spectrometer for measuring hydrocarbon self-diffusion in zeolites. The principles of PFG NMR spectroscopy are illustrated. A pulsed field gradient 60 MHz NMR spectrometer was constructed. Diffusion data were acquired by PFG NMR for standard samples of water, ammonia and glycerol and are in good agreement with those reported in the literature. Following verification of spectrometer performance, the self-diffusion coefficients of isobutane in cation exchanged Y type zeolites were determined. The results show that the mobility of molecules in zeolites depends on the nature of the cations. For small crystallite zeolites, intercrystalline and intracrystalline diffusion has been observed. The effective diffusion coefficients strongly depend on the concentration of adsorbate as well as the packing method. Large discrepancies between diffusion coefficients in zeolites measured by PFG NMR and by adsorption rate experiments have been reported. Surface area, crystallite size, percentage of water in the zeolite, percentage of cation exchanged into the zeolite and other physical chemical properties effect hydrocarbon diffusivity. Detailed methods for determining these properties are discussed. As an extended study of zeolite catalysts, the adsorption of ethylene on

  10. Experimental Demonstration of the Effectiveness of Electromagnetically Induced Transparency for Enhancing Cross-Phase Modulation in the Short-Pulse Regime

    Science.gov (United States)

    Dmochowski, Greg; Feizpour, Amir; Hallaji, Matin; Zhuang, Chao; Hayat, Alex; Steinberg, Aephraim M.

    2016-04-01

    We present an experiment using a sample of laser-cooled Rb atoms to show that cross-phase modulation schemes continue to benefit from electromagnetically induced transparency (EIT) even as the transparency window is made narrower than the signal bandwidth (i.e., for signal pulses much shorter than the response time of the EIT system). Addressing concerns that narrow EIT windows might not prove useful for such applications, we show that while the peak phase shift saturates in this regime, it does not drop, and the time-integrated effect continues to scale inversely with EIT window width. This integrated phase shift is an important figure of merit for tasks such as the detection of single-photon-induced cross-phase shifts. Only when the window width approaches the system's dephasing rate γ does the peak phase shift begin to decrease, leading to an integrated phase shift that peaks when the window width is equal to 4 γ .

  11. Coupling electromagnetic pulse-shaped waves into wire-like interconnection structures with a non-linear protection – Time domain calculations by the PEEC method

    Directory of Open Access Journals (Sweden)

    G. Wollenberg

    2004-01-01

    Full Text Available An interconnection system whose loads protected by a voltage suppressor and a low-pass filter against overvoltages caused by coupling pulse-shaped electromagnetic waves is analyzed. The external wave influencing the system is assumed as a plane wave with HPM form. The computation is provided by a full-wave PEEC model for the interconnection structure incorporated in the SPICE code. Thus, nonlinear elements of the protection circuit can be included in the calculation. The analysis shows intermodulation distortions and penetrations of low frequency interferences caused by intermodulations through the protection circuits. The example examined shows the necessity of using full-wave models for interconnections together with non-linear circuit solvers for simulation of noise immunity in systems protected by nonlinear devices.

  12. Time-resolved absolute measurements by electro-optic effect of giant electromagnetic pulses due to laser-plasma interaction in nanosecond regime

    Science.gov (United States)

    Consoli, F.; de Angelis, R.; Duvillaret, L.; Andreoli, P. L.; Cipriani, M.; Cristofari, G.; di Giorgio, G.; Ingenito, F.; Verona, C.

    2016-06-01

    We describe the first electro-optical absolute measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy. The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation.

  13. A follow-up study of the in-practice results of pulsed electromagnetic field therapy in the management of nonunion fractures

    Directory of Open Access Journals (Sweden)

    Murray HB

    2016-12-01

    Full Text Available Hallie B Murray,1 Brian A Pethica1,2 1EBI, LLC (a Zimmer Biomet company, Parsippany, NJ, USA; 2Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA Abstract: During normal fracture repair, healing occurs within a few months. However, for a minority of patients, the processes of bone repair are compromised or interrupted leading to the development of delayed union and nonunion fractures. Noninvasive bone growth stimulators using pulsed electromagnetic field (PEMF technology are currently in widespread use by patients with impaired fracture healing. This article reports the results of a follow-up study of 1,382 patients treated with PEMF stimulation to evaluate success rates and the relationship between average daily use and the clinical outcomes of therapy as reported by their prescribing physicians. The reported overall success rate for the 1,382 patients was 89.6%. The results were analyzed in audited subsets comparing days of treatment time and average daily use of the electrical bone growth stimulator, using several statistical methods. Linear regression analysis indicated a 6-day reduction in time to heal with each additional hour of average daily use. Survival analysis concluded that the median heal time was reduced by 35%–60%, depending on the different fracture characteristics of patients who complied with the recommended daily use of 10 hours per day. A third statistical analysis indicated that patients treated with the PEMF device for 9 hours or more per day had a significant reduction in time to heal, achieving successful fracture repair an average of 76 days earlier than patients treated with the PEMF device for an average of 3 hours or less per day. Overall, these different methods of statistical analysis indicate that PEMF therapy correlates with an acceleration in the healing of nonunion fractures. Keywords: PEMF, pulsed electromagnetic field, dose–response, nonunion, time to heal

  14. In-situ fabrication of particulate reinforced aluminum matrix composites under high-frequency pulsed electromagnetic field

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Pulsed magnetic field is generated when imposing pulse signal on high-frequency magnetic field. Distribution of the inner magnetic intensity in induction coils tends to be uniform. Furthermore oscillation and disturbance phenomena appear in the melt. Insitu Al2O3 and Al3Zr particulate reinforced aluminum matrix composites have been synthesized by direct melt reaction using Al-Zr(CO3)2 components under a foreign field. The size of reinforced particulates is 2-3 μm. They are well distributed in the matrix.Thermodynamic and kinetic analysis show that high-frequency pulsed magnetic field accelerates heat and mass transfer processes and improves the kinetic condition of in-situ fabrication.

  15. Measurement of Power Density in a Lossy Material by means of Electromagnetically induced acoustic signals for non-invasive determination of spatial thermal absorption in connection with pulsed hyperthermia

    CERN Document Server

    Caspers, Friedhelm

    1982-01-01

    For non-invasive determination of the spatial power density distribution during RF- and microwave hyperthermia it is proposed to apply the electromagnetic energy as short, high intensity pulses. This pulsed signal should have the same average power and thus give the same temperature elevation as the CW source usually applied. Due to the high peak power of the equivalent pulsed signal, with a duty cycle < 1:100, externally measurable thermoacoustic oscillations are induced in the irradiated object. They can be evaluated for the reconstruction of a spatial power density profile.

  16. A comparison of time domain electromagnetic and surface nuclear magnetic resonance sounding for subsurface water on Mars

    Science.gov (United States)

    Grimm, Robert E.

    2003-04-01

    The time domain electromagnetic (TDEM) method has enjoyed wide success in terrestrial groundwater exploration, and the contrast in electrical conductivity between dry overburden and groundwater containing even a small amount of dissolved solids on Mars will yield a robust response. However, moist clays or even ores (e.g., massive hematite) will also be electrically conductive and could be mistaken for aquifers on Mars if proper geologic context is lacking. Surface nuclear magnetic resonance (SNMR) is the only noninvasive geophysical method that responds nearly uniquely to water. As the measured EMF is proportional to the proton-precession frequency, which in turn is proportional to the planet's static magnetic field, SNMR signals are comparatively weak. Using small systems of several kilograms and several watts, the exploration depth of SNMR is one to two orders of magnitude smaller than TDEM: the latter can detect water to depths up to a few kilometers, whereas the former is limited to depths of a few tens of meters. There is no improvement in SNMR signal-to-noise with increasing static field where penetration is controlled by aquifer salinity (skin depth). As reasonable integration times cannot substantially increase the exploration depth, much larger transmitter current or loop mass (either requiring system masses of tens to hundreds of kilograms) are the only way to implement SNMR for exploration to depths of at least hundreds of meters. In spite of some ambiguity in target identification, TDEM is recommended for the first generation of in situ active-source EM measurements for groundwater on Mars.

  17. A Research Program on the Asymptotic Description of Electromagnetic Pulse Propagation in Spatially Inhomogeneous Temporally Dispersive, Attenuative Media

    Science.gov (United States)

    2007-09-01

    significance is debatable as peak amplitude points in the dynamical pulse evolution are arguably not causally related [56] and may or may not convey...of the .Brillouin precursor in a single-resonance Lorentx model dielectric, Pure AppL Opt., 7 (1908), pp. 575-602. [37] A. SoJmMMFW, Uber die

  18. Nuclear Material Detection by One-Short-Pulse-Laser-Driven Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Favalli, Andrea [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Aymond, F. [Univ. of Texas at Austin, TX (United States); Bridgewater, Jon S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Croft, Stephen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deppert, O. [Technische Universitat Darmstadt (Germany); Devlin, Matthew James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Falk, Katerina [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fernandez, Juan Carlos [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gautier, Donald Cort [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gonzales, Manuel A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Goodsell, Alison Victoria [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Guler, Nevzat [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hamilton, Christopher Eric [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hegelich, Bjorn Manuel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henzlova, Daniela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ianakiev, Kiril Dimitrov [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Iliev, Metodi [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Johnson, Randall Philip [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jung, Daniel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kleinschmidt, Annika [Technische Universitat Darmstadt (Germany); Koehler, Katrina Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pomerantz, Ishay [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Roth, Markus [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Santi, Peter Angelo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Shimada, Tsutomu [Los Alamos National Laboratory; Swinhoe, Martyn Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Taddeucci, Terry Nicholas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wurden, Glen Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Palaniyappan, Sasikumar [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); McCary, E. [Univ. of Texas at Austin, TX (United States)

    2015-01-28

    Covered in the PowerPoint presentation are the following areas: Motivation and requirements for active interrogation of nuclear material; laser-driven neutron source; neutron diagnostics; active interrogation of nuclear material; and, conclusions, remarks, and future works.

  19. Fast Two-stage Protector Against Electromagnetic Pulse Based on Electroresistance Effect in Polycrystalline La-Sr(Ca-Mn-O Films

    Directory of Open Access Journals (Sweden)

    Laura ŽURAUSKAITĖ

    2014-06-01

    Full Text Available The electroresistance (ER effect in polycrystalline films of La0.83Sr0.17MnO3 and La0.7Ca0.3MnO3 was investigated in the temperature range of (5 – 290 K using high power sub-nanosecond rise time electrical pulses with amplitude up to 1 kV. It was obtained that conductance vs. voltage dependences are nonlinear and could be well fitted by empirical formula G = G0 + Gα · Uα; where G is conductance, U is the voltage applied across the sample, G0 is the conductance at low voltage, and Gα and α are the parameters related to the electrical transport mechanism. Parameters α for La-Ca-Mn-O and La-Sr-Mn-O were 1.5 and 1.33 respectively. It was obtained that there are two regions of the electroresistance vs. temperature dependence for both films: low temperature region where ER exhibits very slow dependence on temperature and high temperature region where ER significantly decreases with temperature. It was demonstrated that polycrystalline manganite films can be used for the development of protectors against short electromagnetic pulse (EMP, and fast two-stage protector operating at cryogenic temperatures (80 K is proposed. DOI: http://dx.doi.org/10.5755/j01.ms.20.2.6325

  20. International comparison of the properties of NdFeB permanent magnets measured using an electromagnet and a pulsed field magnetometer

    Science.gov (United States)

    Hall, Michael

    2013-08-01

    An IEC TC 68 comparison on the measurement of the magnetic properties of permanent magnets was completed in 2011. Measurements were performed on 6 NdFeB magnets with intrinsic coercivities ranging from 1000 to 2600 kA/m by 8 institutes based in China, Japan, Italy, Belgium, Germany and the UK. Many versions of a Pulsed Field Magnetometer (PFM) that can determine the full BH curve in as little as 100 ms have been developed during the last 2 decades. By comparing measurements made using an internationally accepted electromagnet method and pulsed methods, the influence of the dynamic effects of the latter could be investigated and established. For the quantities remanence, B r , magnetic flux density coercivity, H cB and energy product, BH max the measurements agree within the combined uncertainties. For the intrinsic coercivity, H cJ , the dependence of the measurement of this quantity on the speed at which the magnetic field is reversed was found to be significant with the largest changes in value occurring as a DC measurement condition is approached.

  1. Boron-Proton Nuclear-Fusion Enhancement Induced in Boron-Doped Silicon Targets by Low-Contrast Pulsed Laser

    Directory of Open Access Journals (Sweden)

    A. Picciotto

    2014-08-01

    Full Text Available We show that a spatially well-defined layer of boron dopants in a hydrogen-enriched silicon target allows the production of a high yield of alpha particles of around 10^{9} per steradian using a nanosecond, low-contrast laser pulse with a nominal intensity of approximately 3×10^{16}  W cm^{−2}. This result can be ascribed to the nature of the long laser-pulse interaction with the target and with the expanding plasma, as well as to the optimal target geometry and composition. The possibility of an impact on future applications such as nuclear fusion without production of neutron-induced radioactivity and compact ion accelerators is anticipated.

  2. Measurement of the scintillation time spectra and pulse-shape discrimination of low-energy β and nuclear recoils in liquid argon with DEAP-1

    Science.gov (United States)

    Amaudruz, P.-A.; Batygov, M.; Beltran, B.; Bonatt, J.; Boudjemline, K.; Boulay, M. G.; Broerman, B.; Bueno, J. F.; Butcher, A.; Cai, B.; Caldwell, T.; Chen, M.; Chouinard, R.; Cleveland, B. T.; Cranshaw, D.; Dering, K.; Duncan, F.; Fatemighomi, N.; Ford, R.; Gagnon, R.; Giampa, P.; Giuliani, F.; Gold, M.; Golovko, V. V.; Gorel, P.; Grace, E.; Graham, K.; Grant, D. R.; Hakobyan, R.; Hallin, A. L.; Hamstra, M.; Harvey, P.; Hearns, C.; Hofgartner, J.; Jillings, C. J.; Kuźniak, M.; Lawson, I.; La Zia, F.; Li, O.; Lidgard, J. J.; Liimatainen, P.; Lippincott, W. H.; Mathew, R.; McDonald, A. B.; McElroy, T.; McFarlane, K.; McKinsey, D. N.; Mehdiyev, R.; Monroe, J.; Muir, A.; Nantais, C.; Nicolics, K.; Nikkel, J.; Noble, A. J.; O'Dwyer, E.; Olsen, K.; Ouellet, C.; Pasuthip, P.; Peeters, S. J. M.; Pollmann, T.; Rau, W.; Retière, F.; Ronquest, M.; Seeburn, N.; Skensved, P.; Smith, B.; Sonley, T.; Tang, J.; Vázquez-Jáuregui, E.; Veloce, L.; Walding, J.; Ward, M.

    2016-12-01

    The DEAP-1 low-background liquid argon detector was used to measure scintillation pulse shapes of electron and nuclear recoil events and to demonstrate the feasibility of pulse-shape discrimination down to an electron-equivalent energy of 20 keVee. In the surface dataset using a triple-coincidence tag we found the fraction of β events that are misidentified as nuclear recoils to be cross-section sensitivity of 10-46 cm2, assuming negligible contribution from nuclear recoil backgrounds.

  3. Decoupling Electronic versus Nuclear Photoresponse of Isolated Green Fluorescent Protein Chromophores Using Short Laser Pulses

    Science.gov (United States)

    Kiefer, Hjalte V.; Pedersen, Henrik B.; Bochenkova, Anastasia V.; Andersen, Lars H.

    2016-12-01

    The photophysics of a deprotonated model chromophore for the green fluorescent protein is studied by femtosecond laser pulses in an electrostatic ion-storage ring. The laser-pulse duration is much shorter than the time for internal conversion, and, hence, contributions from sequential multiphoton absorption, typically encountered with ns-laser pulses, are avoided. Following single-photon excitation, the action-absorption maximum is shown to be shifted within the S0 to S1 band from its origin at about 490 to 450 nm, which is explained by the different photophysics involved in the detected action.

  4. Long-term electromagnetic pulse exposure induces Abeta deposition and cognitive dysfunction through oxidative stress and overexpression of APP and BACE1.

    Science.gov (United States)

    Jiang, Da-Peng; Li, Jin-Hui; Zhang, Jie; Xu, Sheng-Long; Kuang, Fang; Lang, Hai-Yang; Wang, Ya-Feng; An, Guang-Zhou; Li, Jing; Guo, Guo-Zhen

    2016-07-01

    A progressively expanded literature has been devoted in the past years to the noxious or beneficial effects of electromagnetic field (EMF) to Alzheimer׳s disease (AD). This study concerns the relationship between electromagnetic pulse (EMP) exposure and the occurrence of AD in rats and the underlying mechanisms, focusing on the role of oxidative stress (OS). 55 healthy male Sprague Dawley (SD) rats were used and received continuous exposure for 8 months. Morris water maze (MWM) test was conducted to test the ability of cognitive and memory. The level of OS was detected by superoxide dismutase (SOD) activity and glutathione (GSH) content. We found that long-term EMP exposure induced cognitive damage in rats. The content of β-amyloid (Aβ) protein in hippocampus was increased after long-term EMP exposure. OS of hippocampal neuron was detected. Western blotting and immunohistochemistry (IHC) assay showed that the content of Aβ protein and its oligomers in EMP-exposed rats were higher than that of sham-exposed rats. The content of Beta Site App Cleaving Enzyme (BACE1) and microtubule-associated protein 1 light chain 3-II (LC3-II) in EMP-exposed rats hippocampus were also higher than that of sham-exposed rats. SOD activity and GSH content in EMP-exposed rats were lower than sham-exposed rats (pEMP exposure-induced OS, including increased amyloid precursor protein (APP) aberrant cleavage. Although further study is needed, the present results suggest that long-term EMP exposure is harmful to cognitive ability in rats and could induce AD-like pathological manifestation.

  5. Complementary Electromagnetic Non-Destructive Evaluation

    Science.gov (United States)

    Tian, Gui Yun; Wilson, John; Morozov, Maxim

    2011-06-01

    The use of non-destructive evaluation (NDE) for defect detection and failure prediction in structures and specimens is widespread in energy industries, aimed at ageing power plants and pipelines, material degradation, fatigue and radiation damage, etc. At present there are no suitable electromagnetic NDE methods for the measurement and characterization of material degradation, in irradiated samples in particular, which is very important and timely for the nuclear power industry in the UK. This paper reports recent developments in the field of electromagnetic (EM) NDE at Newcastle University, including pulsed eddy current (PEC), pulsed magnetic flux leakage (PMFL), magnetic Barkhausen emission (MBE) and magneto-acoustic emission (MAE). As different EM methods have different strengths, an integrative EM framework is introduced. Case studies through the second round robin tests organized by the Universal Network for Magnetic Non-Destructive Evaluation (UNMNDE), representing eighteen leading research groups worldwide in the area of electromagnetic NDE, are reported. Twelve samples with different ageing times and rolling reduction ratios were tested using different magnetic methods among the UNMNDE members. Based on the studies, the complementary characteristics of electromagnetic techniques for NDE are discussed.

  6. Electromagnetic Pulse Excitation of Finite-Long Dissipative Conductors over a Conducting Ground Plane in the Frequency Domain.

    Energy Technology Data Exchange (ETDEWEB)

    campione, salvatore; Warne, Larry K.; Schiek, Richard; Basilio, Lorena I.

    2017-09-01

    This report details the modeling results for the response of a finite-length dissipative conductor interacting with a conducting ground to a hypothetical nuclear device with the same output energy spectrum as the Fat Man device. We use a frequency-domain method based on transmission line theory and implemented it in a code we call ATLOG - Analytic Transmission Line Over Ground. Select results are compared to ones computed using the circuit simulator Xyce. Intentionally Left Blank

  7. Membrane Heating in Living Tissues Exposed to Nonthermal Pulsed EM Fields

    CERN Document Server

    Pierro, V; Croce, R P; Pinto, I M

    2014-01-01

    A bio tissue model consisting of multilayer spherical cells including four nested radial domains (nucleus, nuclear membrane, cytoplasm and plasma membrane) is worked out to derive the cell heating dynamics in presence of membrane capacitance dispersion under pulsed electromagnetic exposure. Two possible cases of frequency-dependent membrana models are discussed: plasma and nuclear membranes are dispersive, only the nuclear memebrane is dispersive . In both models an high localized heating of the membranes occurs, without significant temperature rise in the cytoplasm and nucleoplasm.

  8. Simulation of Electromagnetic Propulsion System Driven by Paralleled Multi-module Pulse Transformers%多模块脉冲变压器并联驱动电磁推进系统仿真

    Institute of Scientific and Technical Information of China (English)

    李海涛; 董亮; 王亮; 吴锐; 王豫

    2012-01-01

    为了探索多模块脉冲变压器并联的脉冲功率源用于电磁推进系统的可行性,建立了多模块脉冲变压器并联电路及其驱动电磁推进系统的数学模型,仿真分析了多模块脉冲变压器并联输出特性、多模块并联下电磁推进系统的推进特性,以及放电时脉冲变压器过电压的限制措施等.脉冲变压器模块数为20,储能100kJ,理想情况下仿真得到的抛体发射速度达到1.5km/s,发射效率为12.6%.仿真结果表明,多模块脉冲变压器并联作为脉冲电源用于电磁推进系统是可行的,有利于电磁发射系统体积的减小,对脉冲变压器过电压抑制可引入非线性电阻.%To explore the feasibility of applying pulsed power supply with paralleled multi-module pulse transformers in electromagnetic propulsion system, the multi-module pulse transformers parallel circuit and the mathematical model of electromagnetic propulsion system were established. The output characteristics of paralleled multi-module pulse transformers and the propulsive characteristics of the electromagnetic propulsion system based on paralleled multi- module were simulated and analyzed. The overvoltage restrictions of pulse transformer at the time of discharge was also analyzed. The number of pulse transformer modules is 20, and the stored energy is 100 kJ. In ideal situation,the simulated launch-speed of the projectile is 1.5 km/s,and the launch efficiency is 12.6%. It is feasible that paralleled multi-module pulse transformers used as pulsed power is applied to electromagnetic propulsion system ,and it is beneficial to decreasing the volume of whole device. Non-linear resistor can be used for pulse transformer overvoltage suppression.

  9. Electromagnetic Pulse Excitation of Finite-Long Dissipative Conductors over a Conducting Ground Plane in the Time Domain.

    Energy Technology Data Exchange (ETDEWEB)

    campione, salvatore; Warne, Larry K.; Schiek, Richard; Basilio, Lorena I.

    2017-09-01

    This report details the modeling results for the response of a finite-length dissipative conductor interacting with a conducting ground to a hypothetical nuclear device with the same output energy spectrum as the Fat Man device. We use a time-domain method based on transmission line theory that allows accounting for time-varying air conductivities. We implemented such method in a code we call ATLOG - Analytic Transmission Line Over Ground. Results are compared the frequency-domain version of ATLOG previously developed and to the circuit simulator Xyce in some instances. Intentionally Left Blank

  10. Finite element modeling and analysis of electro-magnetic pulse welding of aluminium tubes to steel bars

    Science.gov (United States)

    Kumar, Ramesh; Doley, Jyoti; Kore, Sachine

    2016-10-01

    Magnetic pulse welding is a high-speed, solid-state welding process that is applicable to sheets or tube-to-tube or tube-to-bar configurations. In this article we discuss about the MPW process modeling and simulation for welding Al tubes to steel bars. Finite element simulation was done to weld 6061 Al tubes of 1.65 mm wall thickness to 1010 steel bars of a 47.6 mm nominal diameter. Simulation results indicate that Al tubes can be successfully welded to steel bars using MPW. It is found that the standoff distance between the Al tube and the steel bar i.e. gap between inner diameter of Al tube and diameter of steel bar is a dominant factor for achieving a sound weld. The addition of receding angles to the bars can promote MPW weldability window.

  11. 一种电磁脉冲前门耦合效应的事件分解评估方法%An affair-decomposability evaluation method to calculate the front-door coupling effect of electromagnetic pulse

    Institute of Scientific and Technical Information of China (English)

    肖金石; 任雄伟; 樊强

    2013-01-01

    电磁脉冲弹是一种利用辐射高功率电磁脉冲干扰/毁伤目标电子系统的新概念武器.为计算电磁脉冲通过前门耦合毁伤目标的效能,提出一种基于事件分解的效能评估方法,按时间序列将前门耦合-毁伤过程分为弹体爆炸辐射电磁脉冲、大气传输衰减、目标系统耦合3个子事件,分别用不同算法计算其发生效能.用该方法对美国MK84导弹搭载的电磁脉冲弹进行评估,得到具有一定参考价值的效能评估值.%Electromagnetic pulse (EMP) bomb is a kind of new concept weapon,which can be used to disturb or damage electronic system by radiating high power electromagnetic pulse. To calculate damage efficiency of high power EMP through front-door coupling, a kind of efficiency evaluation method based on affair-decomposability is raised. Front-door coupling - damage course is decomposed into three affairs in chronological sequence, which is EMP bomb radiating power, electromagnetic energy transmission and electromagnetic energy coupling into target system. Efficiency of these three affairs is calculated with different algorithms. Finally, type MK 84 electromagnetic pulse bomb of USA is evaluated using this method. Some conclusions about efficiency evaluation are gotten.

  12. 某工程地下人防指挥所防电磁脉冲施工技术%Underground Civil Air Defense Command Post Against An Electromagnetic Pulse Construction

    Institute of Scientific and Technical Information of China (English)

    苏健康

    2011-01-01

    某工程地下指挥所为4B级地下指挥所,对电磁脉冲防护要求高,通过采取接地降阻、管线处理、混凝土裂缝控制及结构钢筋屏蔽笼等施工技术措施,地下人防指挥所防电磁脉冲达到设计要求,一次通过各方验收。%A underground command center of 4B level, which is in protection of high electromagnetic pulse resistance .By the way of taking ground to reduce electromagnetic pulse resistance, pipeline processing, concrete crack controlling and steel cage shield etc.,

  13. An Improved Nuclear Recoil Calibration in the LUX Detector Using a Pulsed D-D Neutron Generator

    Science.gov (United States)

    Huang, Dongqing

    2017-01-01

    The LUX dark matter search experiment is a 370 kg (250 kg active mass) two-_phase liquid/gas xenon time projection chamber located at the 4850 ft level of the Sanford Underground Research Facility in Lead, SD. The first absolute charge (Qy) and light (Ly) measurement performed in situ in the LUX detector with a D-D calibration technique for nuclear recoil spanning 0.7 to 74 keV and 1.1 to 74 keV respectively have been reported in. The D-D calibration has subsequently been further improved by incorporating pulsing technique, i.e. the D-D neutron production is concentrated within narrow pulses (20 us / 250 Hz) with the timing information recorded. This technique allows the suppression of accidental backgrounds in D-D neutron data and also provides increased sensitivity for the lower energy NR calibrations. I will report the improved NR absolute Qy and Ly measurements using the pulsed D-D calibration technique performed in situ in the LUX detector. Brown University, Large Underground Xenon(LUX) Collaboration.

  14. Electromagnetic field analysis and RFEC signal modeling for gap measurement between liquid injection nozzle and nuclear fuel channel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Hoon; Jung, Hyun Kyu; Cheong, Yong Moo; Huh, Young; Lee, Yoon Sang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2004-05-15

    Fuel channels including pressure tube(Pt) and calandria tube(CT) are important components of pressurized heavy water reactor(PHWR). A sagging of fuel channel increases by heat and radiation exposure with the increasing operation time. The contact of fuel channel to liquid injection nozzle(LIN) is thus a critical issue in power plant safety. In order to solve this safety issue, the electromagnetic technique was applied to compliment the present inspection technology. Electromagnetic fields were investigated for the gap measurement between CT and LIN using FEM computer modeling. We calculated the electromagnetic fields, such as, magnetic flux density, current density near the fuel channel and checked the adaptability of RFEC technology. The RFEC Signals using the volume integral method(VIM) were simulated for obtaining the optimal inspection parameters, including frequency, inter-coil spacing, coil size and configuration. Finally, we development the remote field eddy current sensor that can CT/LIN gap measurement efficiently.

  15. The effect of pulsed electromagnetic frequency therapy on health-related quality of life in military service members with chronic low back pain.

    Science.gov (United States)

    Nayback-Beebe, Ann Marie; Yoder, Linda H; Goff, Brandon J; Arzola, Sonya; Weidlich, Christopher

    2017-07-20

    In the U.S. military, chronic low back pain is among the most frequent complaints for medical visits, lost work time, and attrition from active duty and the deployed setting by service members. The aim of this pilot study was to determine whether adjunctive treatment with pulsed electromagnetic frequency (PEMF) produced significant variability in chronic low back pain symptoms and secondary health-related quality of life, mental health and disability outcomes. Prospective, randomized pilot study with repeated measures at baseline, post-treatment, and 1 month follow-up for two groups: usual care (UC) vs. UC + PEMF. In a convenience sample of 75 service members, health-related quality of life mental and physical component scores were significant: F(2, 104) = 4.20, p = .018 (η(2) = .075) and F(2, 104) = 4.75, p = .011 (η(2) = .084), respectively; as was anxiety symptom severity: F(2, 104) = 5.28, p = .007 (η(2) = .092). Adjunctive treatment with PEMF demonstrated improvements in service members' overall physical health-related quality of life with expected, yet statistically nonsignificant improvements in reported pain and LBP-related disability. There were significant between group differences in anxiety symptom severity with higher symptoms reported by the UC + PEMF group, surprising findings that warrant further investigation. Published by Elsevier Inc.

  16. Pulsed electromagnetic fields promote osteogenesis and osseointegration of porous titanium implants in bone defect repair through a Wnt/β-catenin signaling-associated mechanism

    Science.gov (United States)

    Jing, Da; Zhai, Mingming; Tong, Shichao; Xu, Fei; Cai, Jing; Shen, Guanghao; Wu, Yan; Li, Xiaokang; Xie, Kangning; Liu, Juan; Xu, Qiaoling; Luo, Erping

    2016-01-01

    Treatment of osseous defects remains a formidable clinical challenge. Porous titanium alloys (pTi) have been emerging as ideal endosseous implants due to the excellent biocompatibility and structural properties, whereas inadequate osseointegration poses risks for unreliable long-term implant stability. Substantial evidence indicates that pulsed electromagnetic fields (PEMF), as a safe noninvasive method, inhibit osteopenia/osteoporosis experimentally and clinically. We herein investigated the efficiency and potential mechanisms of PEMF on osteogenesis and osseointegration of pTi in vitro and in vivo. We demonstrate that PEMF enhanced cellular attachment and proliferation, and induced well-organized cytoskeleton for in vitro osteoblasts seeded in pTi. PEMF promoted gene expressions in Runx2, OSX, COL-1 and Wnt/β-catenin signaling. PEMF-stimulated group exhibited higher Runx2, Wnt1, Lrp6 and β-catenin protein expressions. In vivo results via μCT and histomorphometry show that 6-week and 12-week PEMF promoted osteogenesis, bone ingrowth and bone formation rate of pTi in rabbit femoral bone defect. PEMF promoted femoral gene expressions of Runx2, BMP2, OCN and Wnt/β-catenin signaling. Together, we demonstrate that PEMF improve osteogenesis and osseointegration of pTi by promoting skeletal anabolic activities through a Wnt/β-catenin signaling-associated mechanism. PEMF might become a promising biophysical modality for enhancing the repair efficiency and quality of pTi in bone defect. PMID:27555216

  17. Effect of Pulsed Electromagnetic Field on Bone Formation and Lipid Metabolism of Glucocorticoid-Induced Osteoporosis Rats through Canonical Wnt Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yuan Jiang

    2016-01-01

    Full Text Available Pulsed electromagnetic field (PEMF has been suggested as a promising method alternative to drug-based therapies for treating osteoporosis (OP, but the role of PEMF in GIOP animal models still remains unknown. This study was performed to investigate the effect of PEMF on bone formation and lipid metabolism and further explored the several important components and targets of canonical Wnt signaling pathway in GIOP rats. After 12 weeks of intervention, bone mineral density (BMD level of the whole body increased significantly, serum lipid levels decreased significantly, and trabeculae were thicker in GIOP rats of PEMF group. PEMF stimulation upregulated the mRNA and protein expression of Wnt10b, LRP5, β-catenin, OPG, and Runx2 and downregulated Axin2, PPAR-γ, C/EBPα, FABP4, and Dkk-1. The results of this study suggested that PEMF stimulation can prevent bone loss and improve lipid metabolism disorders in GIOP rats. Canonical Wnt signaling pathway plays an important role in bone formation and lipid metabolism during PEMF stimulation.

  18. Adenosine Receptors as a Biological Pathway for the Anti-Inflammatory and Beneficial Effects of Low Frequency Low Energy Pulsed Electromagnetic Fields

    Science.gov (United States)

    Vincenzi, Fabrizio; Ravani, Annalisa; Pasquini, Silvia; Merighi, Stefania; Setti, Stefania; Cadossi, Matteo; Cadossi, Ruggero

    2017-01-01

    Several studies explored the biological effects of low frequency low energy pulsed electromagnetic fields (PEMFs) on human body reporting different functional changes. Much research activity has focused on the mechanisms of interaction between PEMFs and membrane receptors such as the involvement of adenosine receptors (ARs). In particular, PEMF exposure mediates a significant upregulation of A2A and A3ARs expressed in various cells or tissues involving a reduction in most of the proinflammatory cytokines. Of particular interest is the observation that PEMFs, acting as modulators of adenosine, are able to increase the functionality of the endogenous agonist. By reviewing the scientific literature on joint cells, a double role for PEMFs could be hypothesized in vitro by stimulating cell proliferation, colonization of the scaffold, and production of tissue matrix. Another effect could be obtained in vivo after surgical implantation of the construct by favoring the anabolic activities of the implanted cells and surrounding tissues and protecting the construct from the catabolic effects of the inflammatory status. Moreover, a protective involvement of PEMFs on hypoxia damage in neuron-like cells and an anti-inflammatory effect in microglial cells have suggested the hypothesis of a positive impact of this noninvasive biophysical stimulus. PMID:28255202

  19. Oxidative stress is reduced in Wistar rats exposed to smoke from tobacco and treated with specific broad-band pulse electromagnetic fields

    Directory of Open Access Journals (Sweden)

    Bajić V.

    2009-01-01

    Full Text Available There have been a number of attempts to reduce the oxidative radical burden of tobacco. A recently patented technology, pulse electromagnetic technology, has been shown to induce differential action of treated tobacco products versus untreated products on the production of reactive oxygen species (ROS in vivo. In a 90-day respiratory toxicity study, Wistar rats were exposed to cigarette smoke from processed and unprocessed tobacco and biomarkers of oxidative stress were compared with pathohistological analysis of rat lungs. Superoxide dismutase (SOD activity was decreased in a dose-dependent manner to 81% in rats exposed to smoke from normal cigarettes compared to rats exposed to treated smoke or the control group. These results correspond to pathohistological analysis of rat lungs, in which those rats exposed to untreated smoke developed initial signs of emphysema, while rats exposed to treated smoke showed no pathology, as in the control group. The promise of inducing an improved health status in humans exposed to smoke from treated cigarettes merits further investigation.

  20. Adenosine Receptors as a Biological Pathway for the Anti-Inflammatory and Beneficial Effects of Low Frequency Low Energy Pulsed Electromagnetic Fields

    Directory of Open Access Journals (Sweden)

    Katia Varani

    2017-01-01

    Full Text Available Several studies explored the biological effects of low frequency low energy pulsed electromagnetic fields (PEMFs on human body reporting different functional changes. Much research activity has focused on the mechanisms of interaction between PEMFs and membrane receptors such as the involvement of adenosine receptors (ARs. In particular, PEMF exposure mediates a significant upregulation of A2A and A3ARs expressed in various cells or tissues involving a reduction in most of the proinflammatory cytokines. Of particular interest is the observation that PEMFs, acting as modulators of adenosine, are able to increase the functionality of the endogenous agonist. By reviewing the scientific literature on joint cells, a double role for PEMFs could be hypothesized in vitro by stimulating cell proliferation, colonization of the scaffold, and production of tissue matrix. Another effect could be obtained in vivo after surgical implantation of the construct by favoring the anabolic activities of the implanted cells and surrounding tissues and protecting the construct from the catabolic effects of the inflammatory status. Moreover, a protective involvement of PEMFs on hypoxia damage in neuron-like cells and an anti-inflammatory effect in microglial cells have suggested the hypothesis of a positive impact of this noninvasive biophysical stimulus.

  1. Synergistic effect of EMF-BEMER-type pulsed weak electromagnetic field and HPMA-bound doxorubicin on mouse EL4 T-cell lymphoma.

    Science.gov (United States)

    Říhová, Blanka; Etrych, Tomáš; Šírová, Milada; Tomala, Jakub; Ulbrich, Karel; Kovář, Marek

    2011-12-01

    We have investigated the effects of low-frequency pulsed electromagnetic field (LF-EMF) produced by BEMER device on experimental mouse T-cell lymphoma EL4 growing on conventional and/or athymic (nude) mice. Exposure to EMF-BEMER slowed down the growth of tumor mass and prolonged the survival of experimental animals. The effect was more pronounced in immuno-compromised nude mice compared to conventional ones. Acceleration of tumor growth was never observed. No measurable levels of Hsp 70 or increased levels of specific anti-EL4 antibodies were detected in the serum taken from experimental mice before and at different intervals during the experiment, i.e. before solid tumor appeared, at the time of its aggressive growth, and at the terminal stage of the disease. A significant synergizing antitumor effect was seen when EL4 tumor-bearing mice were simultaneously exposed to EMF-BEMER and treated with suboptimal dose of synthetic HPMA copolymer-based doxorubicin, DOX(HYD)-HPMA. Such a combination may be especially useful for heavily treated patients suffering from advanced tumor and requiring additional aggressive chemotherapy which, however, at that time could represent almost life-threatening way of medication.

  2. Effectiveness of an Innovative Pulsed Electromagnetic Fields Stimulation in Healing of Untreatable Skin Ulcers in the Frail Elderly: Two Case Reports

    Directory of Open Access Journals (Sweden)

    Fabio Guerriero

    2015-01-01

    Full Text Available Introduction. Recalcitrant skin ulcers are a major burden in elderly patients. Specifically, chronic wounds result in significant morbidity and mortality and have a profound economic impact. Pulsed electromagnetic fields (PEMFs have proved to be a promising therapy for wound healing. Here we describe the first reported case of an innovative PEMF therapy, Emysimmetric Bilateral Stimulation (EBS, used to successfully treat refractory skin ulcers in two elderly and fragile patients. Case Presentation. Two elderly patients developed multiple chronic skin ulcerations. Despite appropriate treatment, the ulcers showed little improvement and the risk of amputation was high. Both patients underwent daily EBS therapy and standard dressing. After few weeks of treatment, major improvements were observed and all ulcers had healed. Conclusion. In patients with refractory ulceration, EBS therapy may be of real benefit in terms of faster healing. This case supports the supportive role for PEMFs in the treatment of skin ulceration in diabetes and is suggestive of a potential benefit of EBS in this clinical condition.

  3. Effects of magnetic nanoparticle-incorporated human bone marrow-derived mesenchymal stem cells exposed to pulsed electromagnetic fields on injured rat spinal cord.

    Science.gov (United States)

    Cho, Hyunjin; Choi, Yun-Kyong; Lee, Dong Heon; Park, Hee Jung; Seo, Young-Kwon; Jung, Hyun; Kim, Soo-Chan; Kim, Sung-Min; Park, Jung-Keug

    2013-01-01

    Transplanting mesenchymal stem cells into injured lesions is currently under study as a therapeutic approach for spinal cord injury. In this study, the effects of a pulsed electromagnetic field (PEMF) on injured rat spinal cord were investigated in magnetic nanoparticle (MNP)-incorporated human bone marrow-derived mesenchymal stem cells (hBM-MSCs). A histological analysis revealed significant differences in MNP-incorporated cell distribution near the injured site under the PEMF in comparison with that in the control group. We confirmed that MNP-incorporated cells were widely distributed in the lesions under PEMF. The results suggest that MNP-incorporated hBM-MSCs were guided by the PEMF near the injured site, and that PEMF exposure for 8 H per day over 4 weeks promoted behavioral recovery in spinal cord injured rats. The results show that rats with MNP-incorporated hBM-MSCs under a PEMF were more effective on the Basso, Beattie, and Bresnahan behavioral test and suggest that the PEMF enhanced the action of transplanted cells for recovery of the injured lesion.

  4. The hemorheological safety of pulsed electromagnetic fields in postmenopausal women with osteoporosis in southwest China: a randomized, placebo controlled clinical trial.

    Science.gov (United States)

    Liu, Huifang; Yang, Lin; He, Hongchen; Zhou, Jun; Liu, Ying; Wang, Chunyan; Wu, Yuanchao; He, Chengqi

    2013-01-01

    Apart from medications, pulsed electromagnetic fields (PEMFs) are used to treat osteoporosis nowadays. However studies on hemorheological safety of PEMFs were scarce. This randomized, placebo controlled clinical trial assessed whether PEMFs could lead to significant hemorheological changes. Fifty-five postmenopausal women were randomly assigned to receive placebo or PEMFs. Venous blood samples were collected at baseline and after treatment to measure 14 hemorheological determinants. Independent samples t-test, paired samples t-test and chi-squared tests were performed respectively. Relationships between variables were determined by Pearson correlation analysis. Multiple linear stepwise regression analysis was used to explore predictors of selected determinants. No significant differences existed between the placebo and PEMFs groups for any of the 14 hemorheological determinants (P>0.05) or the percentage of patients with hemorheological determinant within reference range (P>0.05). Hematocrit was found to be correlated with BMI (P=0.007). The most significant predictor of blood reduced viscosity at low shear rate was blood viscosity at low shear rate. And blood reduced viscosity at high shear rate was the most important predictor of plasma viscosity. These results showed, compared with placebo, PEMFs treatment of postmenopausal osteoporosis was not associated with adverse changes in hemorheological determinants, which may contribute to venous thromboembolism.

  5. Combined effect of pulsed electromagnetic field and sound wave on In vitro and In vivo neural differentiation of human mesenchymal stem cells.

    Science.gov (United States)

    Choi, Yun-Kyong; Urnukhsaikhan, Enerelt; Yoon, Hee-Hoon; Seo, Young-Kwon; Cho, Hyunjin; Jeong, Jong-Seob; Kim, Soo-Chan; Park, Jung-Keug

    2017-01-01

    Biophysical wave stimulus has been used as an effective tool to promote cellular maturation and differentiation in the construction of engineered tissue. Pulsed electromagnetic fields (PEMFs) and sound waves have been selected as effective stimuli that can promote neural differentiation. The aim of this study was to investigate the synergistic effect of PEMFs and sound waves on the neural differentiation potential in vitro and in vivo using human bone marrow mesenchymal stem cells (hBM-MSCs). In vitro, neural-related genes in hBM-MSCs were accelerated by the combined exposure to both waves more than by individual exposure to PEMFs or sound waves. The combined wave also up-regulated the expression of neural and synaptic-related proteins in a three-dimensional (3-D) culture system through the phosphorylation of extracellular signal-related kinase. In a mouse model of photochemically induced ischemia, exposure to the combined wave reduced the infarction volume and improved post-injury behavioral activity. These results indicate that a combined stimulus of biophysical waves, PEMFs and sound can enhance and possibly affect the differentiation of MSCs into neural cells. Our study is meaningful for highlighting the potential of combined wave for neurogenic effects and providing new therapeutic approaches for neural cell therapy. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:201-211, 2017. © 2016 American Institute of Chemical Engineers.

  6. 电磁脉冲在地下的传播特性研究%Research on Characteristics of Electromagnetic Pulse Propagating into Earth

    Institute of Scientific and Technical Information of China (English)

    王川川; 朱长青; 周星; 谷志锋; 刘登峰

    2012-01-01

    As to the propagation of EMP, the earth is a natural obstacle, so it's very siguificative to research the laws of EMP propagating into earth, which can be used into the electromagnetic protection of cables and devices. In this paper, The propagation laws of High-altitude electromagnetic pulse (HEMP) is researched, and propagation of HEMP, LEMP and UWBEMP, HEMP into earth and above earth are compared. Results show that: the electric field of high frequency EMP in earth weakens rapidly with the increase of depth, strengthens with the decrease of earth conductivity and permittivity, and the pulse width increases with the decrease of earth conductivity, weakens with the increase of polarization angle and azimuth an- gle, but strengthens with the increase of pitching angle. But the electric field of low frequency EMP in earth weakens slowly with the increase of depth. Based on these laws, some electromagnetic protection measures are proposed. The research in this paper is helpful to provide guidance for the protection design of electronic devices in the earth.%对于电磁脉冲的传播来说,大地是一道天然的障碍,因此研究电磁脉冲在地下的传播规律,并将其用于线路和设备的抗电磁干扰,是很有意义的。本文分析了HEMP电场在地下的传播规律,并比较了HEMP和雷电磁脉冲(LEMP)、超宽带电磁脉冲(UWBEMP)在地下的传播情况,比较了HEMP在地下和地上的传播情况,结果表明:高频电磁脉冲电场在地中随深度增加而快速减小,低频电磁脉冲变化较小;高频电磁脉冲电场随大地电导率减小而增大、脉宽变宽,随大地介电常数增大而减小,随入射波极化角和方位角增大而减小,随俯仰角增大而增大。然后,根据电磁脉冲在地下的传播规律提出了电磁防护措施和建议。本文的研究有利于指导地下设备的电磁防护设计。

  7. A simple pulsed drain feedback preamplifier for high resolution high rate nuclear spectroscopy

    Science.gov (United States)

    Lakatos, Tamás; Hegyesi, Gyula; Kalinka, Gábor

    1996-02-01

    A non-optical, pulsed reset technique for use in charge sensitive preamplifiers with Si(Li) X-ray semiconductor detectors of conventional polarity is described. The phenomenon of impact ionization in the field effect transistor is used for charge restoration. The process is controlled via the detector capacitance. The method needs no extra components in the input circuitry. No significant resolution degradation can be detected up to 600 kcps Mn K intensity if following the 5 μs resetting pulse the signal processor is inhibited for 50 μs.

  8. A simple pulsed drain feedback preamplifier for high resolution high rate nuclear spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, T. [Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete; Hegyesi, G. [Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete; Kalinka, G. [Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete

    1996-08-21

    A non-optical, pulsed reset technique for use in charge sensitive preamplifiers with Si(Li) X-ray semiconductor detectors of conventional polarity is described. The phenomenon of impact ionization in the field effect transistor is used for charge restoration. The process is controlled via the detector capacitance. The method needs no extra components in the input circuitry. No significant resolution degradation can be detected up to 600 kcps Mn K intensity if following the 5 {mu}s resetting pulse the signal processor is inhibited for 50 {mu}s. (orig.).

  9. Urinary (1)H Nuclear Magnetic Resonance Metabolomic Fingerprinting Reveals Biomarkers of Pulse Consumption Related to Energy-Metabolism Modulation in a Subcohort from the PREDIMED study.

    Science.gov (United States)

    Madrid-Gambin, Francisco; Llorach, Rafael; Vázquez-Fresno, Rosa; Urpi-Sarda, Mireia; Almanza-Aguilera, Enrique; Garcia-Aloy, Mar; Estruch, Ramon; Corella, Dolores; Andres-Lacueva, Cristina

    2017-04-07

    Little is known about the metabolome fingerprint of pulse consumption. The study of robust and accurate biomarkers for pulse dietary assessment has great value for nutritional epidemiology regarding health benefits and their mechanisms. To characterize the fingerprinting of dietary pulses (chickpeas, lentils, and beans), spot urine samples from a subcohort from the PREDIMED study were stratified using a validated food frequency questionnaire. Urine samples of nonpulse consumers (≤4 g/day of pulse intake) and habitual pulse consumers (≥25 g/day of pulse intake) were analyzed using a (1)H nuclear magnetic resonance (NMR) metabolomics approach combined with multi- and univariate data analysis. Pulse consumption showed differences through 16 metabolites coming from (i) choline metabolism, (ii) protein-related compounds, and (iii) energy metabolism (including lower urinary glucose). Stepwise logistic regression analysis was applied to design a combined model of pulse exposure, which resulted in glutamine, dimethylamine, and 3-methylhistidine. This model was evaluated by a receiver operating characteristic curve (AUC > 90% in both training and validation sets). The application of NMR-based metabolomics to reported pulse exposure highlighted new candidates for biomarkers of pulse consumption and the impact on energy metabolism, generating new hypotheses on energy modulation. Further intervention studies will confirm these findings.

  10. Applications of pulsed nuclear magnetic resonance to chemistry: multiple-pulse NMR, cross polarization, magic-angle spinning annd instrumental design

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, P.D.

    1979-07-01

    Pulsed Nuclear Magnetic Resonance (NMR) has been applied to: (1) Measurements of the prinicpal components of the proton shielding tensors of the hydrides of zirconium chloride and zirconium bromide. Multiple-Pulse techniques have been used to remove static homonuclear dipolar coupling. The anisotropies and isotropic shifts of these tensors have been used to infer the possible locations of the hydrogen within the sandwich-like layers of these unusual compounds. (2) Studies of the oscillatory transfer of magnetic polarization between /sup 1/H and /sup 29/Si in substituted silanes. The technique of J Cross Polarization has been used to enhance sensitivity. The /sup 29/Si NMR shifts of -Si-O- model compounds have been investigated as a possible probe for future studies of the environment of bound oxygen in coal-derived liquids. (3) Measurements of the aromatic fraction of /sup 13/C in whole coals. The techniques of /sup 1/H-/sup 13/C Cross Polarization and Magic-Angle Spinning have been used to enhance sensitivity and remove shift anisotropy. Additional topics described are: (4) Calculation and properties of the broadened lineshape of the shileding Powder Pattern. (5) Calculation of the oscillatory transfer of magnetic polarization for an I-S system. (6) Numerical convolution and its uses. (7) The technique of digital filtering applied in the frequency domain. (8) The designs and properties of four NMR probe-circuits. (9) The design of a single-coil double-resonance probe for combined Magic-Angle Spinning and Cross Polarization. (10) The designs of low Q and high Q rf power amplifiers with emphasis on the rf matching circuitry.

  11. A Nuclear Electromagnetic Pulse (EMP) Vulnerability/Lethality (V/L) Taxonomy With Focus on Component Assessment.

    Science.gov (United States)

    1994-11-01

    Martin 1983) and upset/burnout experiments were performed (Tasca, Peden, and Miletta 1972, Kalab 1981; Thomas and Diloreto 1985; Wenaas and Fromme ...Also, conservation of total current is assumed S÷J-P ). In PNJUNCTION , the previous equations are num erically im plem ented through the Yee Finite...Wenaas, E. P., and D. A. Fromme . "Electronics Malfunction Levels and Related EMP Hardening Approaches for Aircraft." DNA001-84-C-0295, Jaycor, San Diego

  12. Investigation of the behavior of protection elements against field radiated line coupled UWB-pulses

    Directory of Open Access Journals (Sweden)

    R. Krzikalla

    2006-01-01

    Full Text Available To protect electronic systems against electromagnetic interferences in general nonlinear protection circuits are used. These protection circuits are optimized mostly against special transient interferences such as lightning electromagnetic pulses (LEMP or electromagnetic pulses caused by nuclear explosions (NEMP. Previous investigations have shown that these protection elements could be undermined by so-called ultra wideband (UWB pulses. Thereby a direct charge of the UWB-pulse to the elements has been assumed. This assumption was a worst case approximation because in practice UWB-pulses only get into systems by coupling effects. In this investigation the behavior of typical nonlinear protection elements has been tested with field radiated line coupled UWB-pulses. For that line coupled UWB-pulses have been defined depending on the coupling behavior of typical electronic systems and a possibility of generation of this kind of pulses is presented. After it typical nonlinear protection elements such as spark gaps, varistors and protection diodes have been tested with the previously defined test pulses. Finally the measured behavior of the elements has been compared with the behavior by direct charged UWB-pulses and the protection effect of the elements against field radiated line coupled UWB-pulses is re-evaluated.

  13. 脉冲电磁场对大鼠破骨细胞功能分子的影响%Effect of pulsed electromagnetic fields on rat osteoclasts

    Institute of Scientific and Technical Information of China (English)

    黄晶晶; 杨福军; 赵吉; 孙元明; 刘晓秋; 沈秀; 赵阿津

    2011-01-01

    Objective To study the effect of pulsed electromagnetic fields (PEMFs) on rat osteoclast rats. Methods Ten-week-old female SD rats were randomly divided into three groups; PEMFs group, CONTROL group, and Sham group. The rats of PEMFs group and CONTROL group were ovariectomized bilaterally. The rats of Sham group were sham-ovariectomized. The rats of PEMFs group were exposed to PEMFs 12 weeks after ovariectomy. However, the rats of the other groups were not treated with PEMFs. Femoral bone marrow of SD rats was collected after PEMFs. The osteoclasts were induced and cultured in vitro. Tartrate-resistant acid phosphatase (TRAP) was measured after 7 days. Immunofluorescence stainings of integrin av33, receptor activator of NF-kB (RANK), and cathepsin K were also measured respectively. Results After exposure to PEMFs, the TRAP measurement showed the morphology of the osteoclast. The immunofluorescence staining showed that positive osteoclasts were significantly reduced. Conclusion PEMFs has inhibitive effect on osteoclasts and can inhibit the bone resorbing activity of the osteoclast in SD rats.%目的 研究脉冲电磁场(puslsed electromagnetic fields,PEMFs)对大鼠破骨细胞的作用.方法 取10w龄雌性SD大鼠随机分为三组:PEMFs组、Control组和Sham组;其中PEMFs组、Control组进行双侧卵巢切除手术,Sham组不切除卵巢.术后12w对PEMFs组大鼠进行PEMFs作用(70Hz,2mT),Control组和Sham组不进行PEMFs作用.作用结束后,取大鼠股骨骨髓,进行体外破骨细胞诱导培养.7天后分别进行破骨细胞的抗酒石酸酸性磷酸酶(Tartrate-resistant acid phosphatase,TRAP)检测和整合素αvβ3、NF-KB受体激活子(receptor activator of NF-KB,RANK)、组织蛋白酶K( cathepsin K)免疫荧光染色检测.结果 经PEMFs作用后,TRAP检测显示破骨细胞形态;免疫荧光染色显示阳性破骨细胞也明显减少.结论 PEMFs对破骨细胞功能分子的表达有抑制作用,提示PEMFs作用可以抑制SD

  14. Design of a randomized controlled trial on the effect on return to work with coaching plus light therapy and pulsed electromagnetic field therapy for workers with work-related chronic stress.

    Science.gov (United States)

    Schoutens, Antonius M C; Frings-Dresen, Monique H W; Sluiter, Judith K

    2016-07-19

    Work-related chronic stress is a common problem among workers. The core complaint is that the employee feels exhausted, which has an effect on the well-being and functioning of the employee, and an impact on the employer and society. The employee's absence is costly due to lost productivity and medical expenses. The usual form of care for work-related chronic stress is coaching, using a cognitive-behavioural approach whose primary aim is to reduce symptoms and improve functioning. Light therapy and pulsed electromagnetic field therapy are used for the treatment of several mental and physical disorders. The objective of this study is to determine whether coaching combined with light therapy plus pulsed electromagnetic field therapy is an effective treatment for reducing absenteeism, fatigue and stress, and improving quality of life compared to coaching alone. The randomized placebo-controlled trial consists of three arms. The population consists of 90 participants with work-related chronic stress complaints. The research groups are: (i) intervention group; (ii) placebo group; and (iii) control group. Participants in the intervention group will be treated with light therapy/pulsed electromagnetic field therapy for 12 weeks, twice a week for 40 min, and coaching (once a fortnight for 50 min). The placebo group receives the same treatment but with the light and pulsed electromagnetic field switched to placebo settings. The control group receives only coaching for 12 weeks, a course of six sessions, once a fortnight for 50 min. The primary outcome is the level of return to work. Secondary outcomes are fatigue, stress and quality of life. Outcomes will be measured at baseline, 6 weeks, 12 and 24 weeks after start of treatment. This study will provide information about the effectiveness of coaching and light therapy plus pulsed electromagnetic field therapy on return to work, and secondly on fatigue, stress and quality of life in people with work-related chronic

  15. Electromagnetic Reciprocity.

    Energy Technology Data Exchange (ETDEWEB)

    Aldridge, David F.

    2014-11-01

    A reciprocity theorem is an explicit mathematical relationship between two different wavefields that can exist within the same space - time configuration. Reciprocity theorems provi de the theoretical underpinning for mod ern full waveform inversion solutions, and also suggest practical strategies for speed ing up large - scale numerical modeling of geophysical datasets . In the present work, several previously - developed electromagnetic r eciprocity theorems are generalized to accommodate a broader range of medi um, source , and receiver types. Reciprocity relations enabling the interchange of various types of point sources and point receivers within a three - dimensional electromagnetic model are derived. Two numerical modeling algorithms in current use are successfully tested for adherence to reciprocity. Finally, the reciprocity theorem forms the point of departure for a lengthy derivation of electromagnetic Frechet derivatives. These mathe matical objects quantify the sensitivity of geophysical electromagnetic data to variatio ns in medium parameters, and thus constitute indispensable tools for solution of the full waveform inverse problem. ACKNOWLEDGEMENTS Sandia National Labor atories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000. Signif icant portions of the work reported herein were conducted under a Cooperative Research and Development Agreement (CRADA) between Sandia National Laboratories (SNL) and CARBO Ceramics Incorporated. The author acknowledges Mr. Chad Cannan and Mr. Terry Pa lisch of CARBO Ceramics, and Ms. Amy Halloran, manager of SNL's Geophysics and Atmospheric Sciences Department, for their interest in and encouragement of this work. Special thanks are due to Dr . Lewis C. Bartel ( recently retired from Sandia National Labo ratories

  16. Contrast generation in the nuclear-spin tomography by pulsed ultrasound; Kontrasterzeugung in der Kernspintomographie durch gepulsten Ultraschall

    Energy Technology Data Exchange (ETDEWEB)

    Oehms, Ole Benjamin

    2009-07-10

    In the framework of this thesis a combined method of ultrasound and nuclear-spin tomography is presented. Via ultrasound pulses by the sound-radiation force in liquids and tissue phantoms motions are generated, which depend on ther viscoelastic properties. This motions are made visible by a motion-sensitive tomograph sequence in the phase image of the tomograph in form of a phase change. The first measurements on simple phantoms and liquids are presented. [German] Im Rahmen dieser Arbeit wird eine kombinierte Methode aus Ultraschall und Kernspintomographie vorgestellt. Ueber Ultraschallpulse werden durch die Schallstrahlungskraft in Fluessigkeiten und Gewebephantomen Bewegungen erzeugt, die von den viskoelastischen Eigenschaften abhaengen. Diese Bewegungen werden mit einer bewegungssensitiven Tomographensequenz im Phasenbild des Tomographen in Form einer Phasenaenderung sichtbar gemacht. Die ersten Messungen an einfachen Phantomen und Fluessigkeiten werden praesentiert. (orig.)

  17. Effect of nuclear motion on high-order harmonic generation of H$_2^+$ in intense ultrashort laser pulses

    CERN Document Server

    Ahmadi, Hamed; Sabzyan, Hassan; Niknam, Ali Reza; Vafaee, Mohsen

    2014-01-01

    High-order harmonic generation is investigated for H$_2^+$ and D$_2^+$ with and without Born-Oppenheimer approximation by numerical solution of full dimensional electronic time-dependent Schr\\"{o}dinger equation under 4-cycle intense laser pulses of 800 nm wavelength and $I$=4, 5, 7, 10 $\\times 10^{14}$ W$/$cm$^2$ intensities. For most harmonic orders, the intensity obtained for D$_2^+$ is higher than that for H$_2^+$, and the yield difference increases as the harmonic order increases. Only at some low harmonic orders, H$_2^+$ generates more intense harmonics compared to D$_2^+$. The results show that nuclear motion, ionization probability and system dimensionality must be simultaneously taken into account to properly explain the isotopic effects on high-order harmonic generation and to justify experimental observations.

  18. Hole-burning in an Autler-Townes doublet and in superluminal (subluminal) Electromagnetically induced transparency of a light pulse via a joint nonlinear coherent Kerr effect and Doppler broadening

    CERN Document Server

    Bacha, Bakhtt A; Ahmad, Iftikhar

    2013-01-01

    We investigate the behavior of light pulse propagation in a 4-level double Lambda atomic system under condition of electromagnetically induced transparency. The Fano type interference effect and spectral hole burning appears in the the dynamics of the absorption-dispersion spectra caused by the joint nonlinear coherence Kerr effect and Doppler broadening. The coherent Kerr effect exhibits an enhancement (reduction) in superluminal (subluminal) in negative (in positive) group index while the Doppler broadening generates multiple hole burning in the Autler-Townes like spectra of this system. The hole burning in addition with coherent Kerr effect on the spectral profile influences the dynamics of subluminal and superluminal of the probe pulse through the medium. The characteristics of superluminality and subluminality modified by considering cold-Kerr-free medium and hot-Kerr-dependent mediums. The light pulse delays and advances in different regions of dispersion medium with the Doppler broadening and coherent ...

  19. Pulsed electromagnetic fields improve bone microstructure and strength in ovariectomized rats through a Wnt/Lrp5/β-catenin signaling-associated mechanism.

    Science.gov (United States)

    Jing, Da; Li, Feijiang; Jiang, Maogang; Cai, Jing; Wu, Yan; Xie, Kangning; Wu, Xiaoming; Tang, Chi; Liu, Juan; Guo, Wei; Shen, Guanghao; Luo, Erping

    2013-01-01

    Growing evidence has demonstrated that pulsed electromagnetic field (PEMF), as an alternative noninvasive method, could promote remarkable in vivo and in vitro osteogenesis. However, the exact mechanism of PEMF on osteopenia/osteoporosis is still poorly understood, which further limits the extensive clinical application of PEMF. In the present study, the efficiency of PEMF on osteoporotic bone microarchitecture and bone quality together with its associated signaling pathway mechanisms was systematically investigated in ovariectomized (OVX) rats. Thirty rats were equally assigned to the Control, OVX and OVX+PEMF groups. The OVX+PEMF group was subjected to daily 8-hour PEMF exposure with 15 Hz, 2.4 mT (peak value). After 10 weeks, the OVX+PEMF group exhibited significantly improved bone mass and bone architecture, evidenced by increased BMD, Tb.N, Tb.Th and BV/TV, and suppressed Tb.Sp and SMI levels in the MicroCT analysis. Three-point bending test suggests that PEMF attenuated the biomechanical strength deterioration of the OVX rat femora, evidenced by increased maximum load and elastic modulus. RT-PCR analysis demonstrated that PEMF exposure significantly promoted the overall gene expressions of Wnt1, LRP5 and β-catenin in the canonical Wnt signaling, but did not exhibit obvious impact on either RANKL or RANK gene expressions. Together, our present findings highlight that PEMF attenuated OVX-induced deterioration of bone microarchitecture and strength in rats by promoting the activation of Wnt/LRP5/β-catenin signaling rather than by inhibiting RANKL-RANK signaling. This study enriches our basic knowledge to the osteogenetic activity of PEMF, and may lead to more efficient and scientific clinical application of PEMF in inhibiting osteopenia/osteoporosis.

  20. Pulsed electromagnetic fields for the treatment of tibial delayed unions and nonunions. A prospective clinical study and review of the literature

    Directory of Open Access Journals (Sweden)

    Assiotis Aggelos

    2012-06-01

    Full Text Available Abstract Background Pulsed electromagnetic fields (PEMF stimulation for the treatment of bone nonunion or delayed union have been in use for several years, but on a limited basis. The aim of this study was to assess the overall efficacy of the method in tibial delayed unions and nonunions and identify factors that could affect the final outcome. Methods We prospectively reviewed 44 patients (27 men with a mean age of 49.6 ± 18.4 years that received PEMF therapy due to tibial shaft delayed union or nonunion. In all cases, fracture gap was less than 1 cm and infection or soft tissue defects were absent. Results Fracture union was confirmed in 34 cases (77.3%. No relationship was found between union rate and age (p = 0.819, fracture side (left or right (p = 0.734, fracture type (simple or comminuted, open or closed (p = 0.111, smoking (p = 0.245, diabetes (p = 0.68 and initial treatment method applied (plates, nail, plaster of paris (p = 0.395. The time of treatment onset didn’t affect the incidence of fracture healing (p = 0.841. Although statistical significance was not demonstrated, longer treatment duration showed a trend of increased probability of union (p = 0.081. Conclusion PEMF stimulation is an effective non-invasive method for addressing non-infected tibial union abnormalities. Its success is not associated with specific fracture or patient related variables and it couldn’t be clearly considered a time-dependent phenomenon.

  1. Effects of 50 Hz pulsed electromagnetic fields on the growth and cell cycle arrest of mesenchymal stem cells: an in vitro study.

    Science.gov (United States)

    Li, Xinping; Zhang, Mingsheng; Bai, Liming; Bai, Wenfang; Xu, Weicheng; Zhu, Hongxiang

    2012-12-01

    Mesenchymal stem cells (MSCs) are capable of self-renew and multipotent differatiation which allows them to be sensitive to microenvironment is altered. Pulsed electromagnetic fields (PEMF) can affect cellular physiology of some types of cells. This study was undertaken to investigate the effects of PEMF on the growth and cell cycle arrest of MSCs expanded in vitro. To achieve this, cultured of normal rat MSCs, the treatment groups were respectively irradiated by 50 Hz PEMF at 10 mT of flux densities for 3 or 6 h. The effects of PEMF on cell proliferation, cell cycle arrest, and cell surface antigen phenotype were investigated. Our results showed that exposed MSCs had a significant proliferative capacity (P cell growth was not different (P>0.05) at an earlier phase after PEMF treatment. Exposure to PEMF had a significant increase the percentage of MSCs in G1 phase compare with the control group, with a higher percentage of cells in G1 phase exposed for 6 h then that for 3 h. At the 16th hour after treatment, PEMF had no significant effect on cell proliferation and cell cycle (P>0.05). These results suggested that PEMF enhanced MSCs proliferation with time-independent and increased the percentage of cells at the G1 phase of the cell cycle in a time-dependent manner, and the effect of PEMF on the cell proliferation and cell cycle arrest of MSCs was temporal after PEMF treatment.

  2. Is there a role of pulsed electromagnetic fields in management of patellofemoral pain syndrome? Randomized controlled study at one year follow-up.

    Science.gov (United States)

    Servodio Iammarrone, Clemente; Cadossi, Matteo; Sambri, Andrea; Grosso, Eugenio; Corrado, Bruno; Servodio Iammarrone, Fernanda

    2016-02-01

    Patellofemoral pain syndrome (PFPS) is a common cause of recurrent or chronic knee pain in young adults, generally located in the retropatellar region. Etiology is controversial and includes several factors, such as anatomical defects, muscular imbalance, or joint overuse. Good results have been reported with exercise therapy, including home exercise program (HEP). Joint inflammation with increase of pro-inflammatory cytokines levels in the synovial fluid might be seen especially when chondromalacia becomes evident. Biophysical stimulation with pulsed electromagnetic fields (PEMFs) has shown anti-inflammatory effects and anabolic chondrocyte activity. The purpose of this randomized controlled study was to evaluate if the combination of HEP with PEMFs was more effective than HEP alone in PFPS treatment. Thirty-one PFPS patients were enrolled in this study. All patients were instructed to train with HEP. Patients in the PEMFs group associated HEP with PEMFs. Function and pain were assessed with Victorian Institute of Sport Assessment score (VISA), Visual Analog Scale (VAS), and Feller's Patella Score at baseline at 2, 6, and 12 months of follow-up. Drug assumption was also recorded. Increase in VISA score was significantly higher in PEMFs group compared to controls at 6 and 12 months, as well as the increase in the Feller's Patella Score at 12 months. VAS score became significantly lower in the PEMFs group with respect to control group since 6 month follow-up. Pain reduction obtained with PEMFs enhanced practicing therapeutic exercises leading to a better recovery process; this is extremely important in addressing the expectations of young patients, who wish to return to sporting activities.

  3. 电磁脉冲试验测试控制及信息管理系统%The Electromagnetic Pulse Experiment Measurement & Control and Information Management System

    Institute of Scientific and Technical Information of China (English)

    杨静; 聂鑫; 王伟; 朱志臻; 石跃武; 孙蓓云; 崔志同

    2015-01-01

    针对高空核电磁脉冲( HEMP)模拟试验需求,研制了一套分布式测试控制与信息管理系统。系统基于网络通信技术,通过虚拟仪器软件架构VISA函数和控件实现与仪器之间的通信,利用NI公司的图形化编程语言LabVIEW实现。系统集硬件控制以及数据采集、信号处理、数据库管理、报表生成等功能于一体,具有高效、规范、可移植性和可扩展性强等特点。系统在实际试验中得到了应用,提高了核电磁脉冲试验工作效率和规范性。%A measurement&control and Information Management System is built for the need of High-altitude Electromagnetic Pulse ( HEMP) Experiment.The distributed management&control system is based on network communication and communicates with other devices with the aid of VISA technology and graphic programming language LabVIEW.The system has the following functions, such as data acquisition, signal processing, data-base management, and report generation, etc.The System is effective and normative, with good transportability and scalability.The system has been used during the HEMP experiment and makes the test more efficient and standard.

  4. Some feature of interpretation of tension single pulsed electromagnetic field of the Earth to create the model parameter fields physical properties

    Directory of Open Access Journals (Sweden)

    Mokritskaya T.P.

    2014-12-01

    Full Text Available Stochastic analysis of the results of different methods of obtaining and processing of information allows us to solve problems on a qualitatively different level. This is important when creating complex earth models and fields of its parameters, particularly the physical properties. Application of remote sensing methods (geophysical investigations with the registration of a single pulse intensity of the electromagnetic field of the Earth (EIEMPZ seismic profiling, is expanding. Interesting results of the joint interpretation of the results of geophysical and laboratory studies of physical soil. Interesting results of the joint interpretation of the results of geophysical and laboratory studies of physical soil. For the first time a methodology for assessing the state of the soil [3] applied for a joint interpretation of materials determine the field strength EMPZ, seismic profiling, and laboratory techniques. This has allowed to characterize the state of the geological environment and to build a model of inhomogeneous density distribution of fractured rocks at depth. In this paper we made a mathematical analysis of the results of research and talus deposits eluvial clay Taurian series, studied at one of the construction sites southern coast at a depth of 12.0 -25.0 m. Methods of statistical analysis, assessment of homogeneity and symmetrically distributed, rank correlation and multiple regression analysis described in [3]. The analysis of the spatial distribution of areas extrem value of EMPZ, heterogeneity of seismic rigidity. Statistical characteristics of indicators of physical properties reflect the genetic characteristics of the formation and the current state of silty-clay sediments of different genesis.It is proved that the regression model can be applied to interpret the state of the array in the construction of geodynamic model. It is established that the creation of forward-looking (dynamic models for the distribution of the physical

  5. Digital pulse processing and optimization of the front-end electronics for nuclear instrumentation.

    Science.gov (United States)

    Bobin, C; Bouchard, J; Thiam, C; Ménesguen, Y

    2014-05-01

    This article describes an algorithm developed for the digital processing of signals provided by a high-efficiency well-type NaI(Tl) detector used to apply the 4πγ technique. In order to achieve a low-energy threshold, a new front-end electronics has been specifically designed to optimize the coupling to an analog-to-digital converter (14 bit, 125 MHz) connected to a digital development kit produced by Altera(®). The digital pulse processing is based on an IIR (Infinite Impulse Response) approximation of the Gaussian filter (and its derivatives) that can be applied to the real-time processing of digitized signals. Based on measurements obtained with the photon emissions generated by an (241)Am source, the energy threshold is estimated to be equal to ~2 keV corresponding to the physical threshold of the NaI(Tl) detector. An algorithm developed for a Silicon Drift Detector used for low-energy x-ray spectrometry is also described. In that case, the digital pulse processing is specifically designed for signals provided by a reset-type preamplifier ((55)Fe source).

  6. Electromagnetic Waves

    DEFF Research Database (Denmark)

    This book is dedicated to various aspects of electromagnetic wave theory and its applications in science and technology. The covered topics include the fundamental physics of electromagnetic waves, theory of electromagnetic wave propagation and scattering, methods of computational analysis...

  7. 静电放电电磁脉冲耦合的非线性优化建模%Nonlinear Optimized Modeling of Electromagnetic Pulse Coupling in Electrostatic Discharge

    Institute of Scientific and Technical Information of China (English)

    樊高辉; 魏明; 刘卫超; 陈翔; 曹艳宾

    2012-01-01

    For the problem that the computing process of electromagnetic pulse response in the existing mechanism modeling algorithms is very complex, a radiation experiment of electrostatic discharge for pulse field sensor is designed in order to offer a simple but effective method for computing electromagnetic pulse response of electronic devices. In the modeling, NARX Neural Network (NN NARX) is substituted for the conventional NARX network, and the layer weight matrices and bias vectors are optimized by genetic algorithm (GA). Two models are built and trained on the basis of the 3.5 kV electrostatic discharge experiment data to identify the dynamic characteristics of the system. The electromagnetic pulse response of 4.5 kV electrostatic discharge is predicted by using the models, and the results show that both optimized NN NARX model and conventional NARX model can predict the response wave accurately through comparing the predicted response with the measured data, but the model optimized with NN NARX performs better. The proposed modeling method is easy in use, and also suitable for modeling of other electromagnetic pulse responses.%针对现有机理建模算法普遍存在计算电磁脉冲响应过程过于复杂的问题,为能够给电子设备静电放电电磁脉冲响应计算提供一种简便有效的能量耦合建模方法,设计了脉冲场强测试仪的静电放电辐射实验.用NARX神经网络代替传统NARX网络,依靠遗传算法对网络的初始权值、阈值进行优化,以3.5 kV静电放电实验数据作为建模数据对系统进行非线性辨识,并对4.5 kV静电放电电磁脉冲响应进行预测.建模结果表明,两种模型均能准确预测响应波形,但优化后的NARX神经网络模型精度更高.该建模方法计算过程简单.该方法同样适用于其他电磁脉冲响应建模.

  8. Nanostructured rhodium films produced by pulsed laser deposition for nuclear fusion applications

    Science.gov (United States)

    Passoni, M.; Dellasega, D.; Grosso, G.; Conti, C.; Ubaldi, M. C.; Bottani, C. E.

    2010-09-01

    In this paper the possibilities offered by pulsed laser deposition (PLD) for the production of nanostructured rhodium films with improved properties are explored. Thanks to its high reflectivity and low sputtering yield, rhodium is one of the best candidates for the development of thin films to be used in first mirrors, which are crucial components in many diagnostic systems of thermonuclear magnetic fusion machines, like tokamaks. Due to the features of PLD, by varying the process parameters it is possible to tailor both the structure, i.e. the nanocrystalline domain size of the deposited films, down to less than 5 nm and separately control the other relevant physical properties. This leads to modifications in growth regime and annealing dynamics, in such a way that both morphology and reflectivity achieve the properties demanded to use these films as mirrors for fusion applications, opening at the same time new possibilities for the future improvement of thermo-mechanical and adhesion properties.

  9. Characterization of a pulsed mode high voltage power supply for nuclear detectors

    Science.gov (United States)

    Ghazali, A. B.; Ahmad, T. S.; Abdullah, N. A.

    2013-06-01

    This paper discusses the characterization of a pulsed mode high voltage power supply (HVPS) using LT1073 chip. The pulsed modulated signal generated from this chip is amplified using a step-up ferrite core transformer of 1:20 turn ratio and then further multiplied and converted into DC high voltage output using a diode-capacitor arrangement. The circuit is powered by a 9V alkaline battery but regulated at 5V supply. It was found that the output for this setup is 520V, 87 μA with 10% load regulation. This output is suitable to operate a pancake-type GM detector, typically model LND 7317 where the plateau is from 475V to 675V. It was also found that when a β-source with intensity of 120 cps is used, the power consumption of the circuit is 5 V, 10.1 mA only. When the battery was left 'on' for 40 hours continuously, the battery's voltage has dropped to 6.9V, meaning that the 5V supply as well as 520V output is still maintained. It is noted that the minimum output voltage of 475V has reached when the regulated supply has reduced to 4.6V and consequently the 9V battery dropped to 6.5V, and this had happened after approximately 3 days of continuous operation. The power efficiency for this circuitry was found to be 89.5%. This result has far better in performance since the commercial portable equipment of this type has normally specified that not less than 8 hours continuous operation only. On the circuit design for this power supply, it was found that the enveloped frequency is 133 Hz with approximately 50% duty cycle. The modulated frequency during 'on' state was found to be 256 KHz in which the majority of power consumption is required.

  10. Detailed Characterization of Nuclear Recoil Pulse Shape Discrimination in the DarkSide-50 Direct Dark Matter Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Edkins, Erin Elisabeth [Univ. of Hawaii, Honolulu, HI (United States)

    2017-05-01

    While evidence of non-baryonic dark matter has been accumulating for decades, its exact nature continues to remain a mystery. Weakly Interacting Massive Particles (WIMPs) are a well motivated candidate which appear in certain extensions of the Standard Model, independently of dark matter theory. If such particles exist, they should occasionally interact with particles of normal matter, producing a signal which may be detected. The DarkSide-50 direct dark matter experiment aims to detect the energy of recoiling argon atoms due to the elastic scattering of postulated WIMPs. In order to make such a discovery, a clear understanding of both the background and signal region is essential. This understanding requires a careful study of the detector's response to radioactive sources, which in turn requires such sources may be safely introduced into or near the detector volume and reliably removed. The CALibration Insertaion System (CALIS) was designed and built for this purpose in a j oint effort between Fermi National Laboratory and the University of Hawaii. This work describes the design and testing of CALIS, its installation and commissioning at the Laboratori Nazionali del Gran Sasso (LNGS) and the multiple calibration campaigns which have successfully employed it. As nuclear recoils produced by WIMPs are indistinguishable from those produced by neutrons, radiogenic neutrons are both the most dangerous class of background and a vital calibration source for the study of the potential WIMP signal. Prior to the calibration of DarkSide-50 with radioactive neutron sources, the acceptance region was determined by the extrapolation of nuclear recoil data from a separate, dedicated experiment, ScENE, which measured the distribution of the pulse shape discrimination parameter, $f_{90}$, for nuclear recoils of known energies. This work demonstrates the validity of the extrapolation of ScENE values to DarkSide-50, by direct comparison of the $f_{90}$ distributio n of nuclear

  11. 电子信息设备防雷击电磁脉冲方法研究%Reseach on Method of Electronic and Information Equipment Against Lightning Electromagnetic Pulse

    Institute of Scientific and Technical Information of China (English)

    傅芳; 郭健

    2011-01-01

    The hazards of lightning electromagnetic pulse on electronic and information equipment is introduced, and the cause is analyzed. On the basis of the principle of electromagnetic shielding, the magnetic field strength of the lightning strikes in different regions is analyzed, copper and aluminum mesh grille is made for protection. Finally the protective effect is analyzed.%介绍雷击电磁脉冲对电子信息设备的危害,分析原因,在此基础上,利用电磁屏蔽的原理,分析雷击时,不同屏蔽区域的磁场强度,提出利用铜铝网格格栅进行防护的方法,最后对防护效果进行分析研究.

  12. Low-frequency pulsed electromagnetic fields for treatment of osteoporosis%低频脉冲电磁场治疗骨质疏松的机制及临床应用

    Institute of Scientific and Technical Information of China (English)

    赵琳

    2016-01-01

    BACKGROUND: The most commonly used physiotherapies for osteoporosis include low-frequency pulsed electromagnetic field, ultrashort wave therapy, and extracorporeal shock wave therapy. Because of the uncertain intensity of extracorporeal shock wave and uncertain efficacy of ultrasound therapy, low-frequency pulsed electromagnetic fields have become the most widely used treatment for osteoporosis in clinic. OBJECTIVE: To review the mechanism and clinical application of low-frequency pulsed electromagnetic fields in the treatment of osteoporosis. METHODS: A computer search by the first author of PubMed and CNKI databases was performed for relevant articles using the keywords of “pulsed electromagnetic fields and osteoporosis” or “osteoblast or osteoclast” in English and “osteoporosis; pulsed pulsed electromagnetic fields; osteoblasts; osteoclasts” in Chinese, respectively. After initial search, there were 169 articles, and according to the inclusion criteria, 29 highly relevant articles that are authentic and have clear views were analyzed. RESULTS AND CONCLUSION: The pulsed electromagnetic field as a non-drug therapy is characterized by no trauma, no infection, simple operation, low cost, long-term use, and good safety. Its efficacy has been increasingly affirmed by researchers and clinicians. Pulsed electromagnetic fields can promote the synthesis of DNA, influence the proliferation and differentiation of osteoblasts, increase the apoptosis of osteoclasts, and have a certain window effect. Pulsed electromagnetic fields can effectively relieve pain and increase bone density level in patients with osteoporosis, which can increase its efficacy in combination with other drugs and have a wide range of clinical applications.%背景:目前常用的骨质疏松症物理治疗方法主要有低频脉冲电磁场疗法、超短波疗法、体外冲击波疗法等,但体外冲击波疗法的强度剂量问题尚未解决,超声疗法

  13. Importance of nuclear triaxiality for electromagnetic strength, level density and neutron capture cross sections in heavy nuclei

    CERN Document Server

    Grosse, Eckart; Massarczyk, Ralph

    2014-01-01

    Cross sections for neutron capture in the range of unresolved resonances are predicted simultaneously to level distances at the neutron threshold for more than 100 spin-0 target nuclei with A >70. Assuming triaxiality in nearly all these nuclei a combined parameterization for both, level density and photon strength is presented. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians adding up to the TRK sum rule and theory-based predictions for the A-dependence of pole energies and spreading widths. For the small spins reached by capture level densities are well described by only one free global parameter; a significant collective enhancement due to the deviation from axial symmetry is observed. Reliable predictions for compound nuclear reactions also outside the valley of stability as expected from the derived global parameterization are important for nuclear astrophysics and for the transmutation of nuclear waste.

  14. Pulsed Bromine-81 Nuclear Quadrupole Resonance Spectroscopy of Brominated Flame Retardants and Associated Polymer Blends.

    Science.gov (United States)

    Mrse, Anthony A.; Lee, Youngil; Bryant, Pamela L.; Fronczek, Frank R.; Butler, Leslie G.; Simeral, Larry S.

    1998-03-01

    The dispersion of brominated flame retardants in polymers is monitored with bromine-81 NQR using a pulse NQR spectrometer. The NQR spectrometer consists of a homemade 10-300 MHz single-channel NMR console coupled to a broadly tunable probe. The probe is a loop-gap resonator usable from 220 to 300 MHz, and automatically tuned over any 5 MHz region with a stepping motor and an RF bidirectional coupler. Bromine-81 NQR spectra of several brominated aromatic flame retardants, as pure materials and in polymers, were recorded in the range of 227 to 256 MHz in zero applied magnetic field. Two factors affect the bromine-79/81 NQR transition frequencies in brominated aromatics: electron withdrawing substituents on the ring and intermolecular contacts with other bromine atoms in the crystal structure. An existing model for substituents is updated and a point charge model for the intermolecular contacts is developed. In this study, we exploit the bromine-81 NQR transition frequency dependence on intermolecular contacts to learn how a flame retardant is dispersed in a polymer matrix.

  15. Response Analysis on Electrical Pulses under Severe Nuclear Accident Temperature Conditions Using an Abnormal Signal Simulation Analysis Module

    Directory of Open Access Journals (Sweden)

    Kil-Mo Koo

    2012-01-01

    Full Text Available Unlike design basis accidents, some inherent uncertainties of the reliability of instrumentations are expected while subjected to harsh environments (e.g., high temperature and pressure, high humidity, and high radioactivity occurring in severe nuclear accident conditions. Even under such conditions, an electrical signal should be within its expected range so that some mitigating actions can be taken based on the signal in the control room. For example, an industrial process control standard requires that the normal signal level for pressure, flow, and resistance temperature detector sensors be in the range of 4~20 mA for most instruments. Whereas, in the case that an abnormal signal is expected from an instrument, such a signal should be refined through a signal validation process so that the refined signal could be available in the control room. For some abnormal signals expected under severe accident conditions, to date, diagnostics and response analysis have been evaluated with an equivalent circuit model of real instruments, which is regarded as the best method. The main objective of this paper is to introduce a program designed to implement a diagnostic and response analysis for equivalent circuit modeling. The program links signal analysis tool code to abnormal signal simulation engine code not only as a one body order system, but also as a part of functions of a PC-based ASSA (abnormal signal simulation analysis module developed to obtain a varying range of the R-C circuit elements in high temperature conditions. As a result, a special function for abnormal pulse signal patterns can be obtained through the program, which in turn makes it possible to analyze the abnormal output pulse signals through a response characteristic of a 4~20 mA circuit model and a range of the elements changing with temperature under an accident condition.

  16. 电磁脉冲与电路之间能量耦合辨识建模方法%Modeling of Energy Coupling Identification Between Electromagnetic Pulse and Circuit

    Institute of Scientific and Technical Information of China (English)

    樊高辉; 魏明; 刘卫超

    2011-01-01

    For the ubiquity problems that the process computing electromagnetic pulse response by the existing mechanism modeling algorithms is too complex, in order to study the new methods of simulating electromagnetic pulse effects based on experiment data, the way that the electromagnetic pulse energy cou-pls to regulated power supply is researched by system identification. The input signals are step signals and square wave produced by standard signal generator. The model of the energy coupling transfer function is bulit by Output Error (OE) model based on least square algorithm, and check the predictive ability of the model by different amplitude input and output experiment data. As a result, the model can predict the wave shape well, and the goodness of fit on the step signal wave shape are 90. 1% ,78. 7% and 76. 0% re-spectivately, then that of the square wave is 61. 4%. The result approves the effective application of system identification in electromagnetic pulse response modeling.%针对现有机理建模算法普遍存在计算电磁脉冲过于复杂的问题,探索基于实验统计的电磁脉冲效应仿真新方法,利用系统辨识,对以集成稳压电源电路为实验对象的电磁脉冲能量耦合建模进行了研究.由标准信号发生器产生的阶跃信号和方波信号作为激励,基于最小二乘法的OE(output error)模型对能量耦合传递函数进行建模,并用不同幅度的激励及其响应实测数据验证辨识所得模型的预测能力.结果表明,所得模型能较好地预测出响应波形,阶跃信号波形拟合度分别为90.1%,78.7%,76.0%,方波信号拟合度为61.4%.证实了利用系统辨识对电磁脉冲响应建模的正确性.

  17. Electromagnetic Waves

    DEFF Research Database (Denmark)

    This book is dedicated to various aspects of electromagnetic wave theory and its applications in science and technology. The covered topics include the fundamental physics of electromagnetic waves, theory of electromagnetic wave propagation and scattering, methods of computational analysis......, material characterization, electromagnetic properties of plasma, analysis and applications of periodic structures and waveguide components, etc....

  18. Pulsed and monoenergetic beams for neutron cross-section measurements using activation and scattering techniques at Triangle Universities Nuclear Laboratory

    Science.gov (United States)

    Hutcheson, A.; Angell, C. T.; Becker, J. A.; Boswell, M.; Crowell, A. S.; Dashdorj, D.; Fallin, B.; Fotiades, N.; Howell, C. R.; Karwowski, H. J.; Kelley, J. H.; Kiser, M.; Macri, R. A.; Nelson, R. O.; Pedroni, R. S.; Tonchev, A. P.; Tornow, W.; Vieira, D. J.; Weisel, G. J.; Wilhelmy, J. B.

    2007-08-01

    In support of the Stewardship Science Academic Alliances initiative, an experimental program has been developed at Triangle Universities Nuclear Laboratory (TUNL) to measure (n,xn) cross-sections with both in-beam and activation techniques with the goal of improving the partial cross-section database for the NNSA Stockpile Stewardship Program. First experimental efforts include excitation function measurements on 235,238U and 241Am using pulsed and monoenergetic neutron beams with En = 5-15 MeV. Neutron-induced partial cross-sections were measured by detecting prompt γ rays from the residual nuclei using various combinations of clover and planar HPGe detectors in the TUNL shielded neutron source area. Complimentary activation measurements using DC neutron beams have also been performed in open geometry in our second target area. The neutron-induced activities were measured in the TUNL low-background counting area. In this presentation, we include detailed information about the irradiation procedures and facilities and preliminary data on first measurements using this capability.

  19. Pulsed and monoenergetic beams for neutron cross-section measurements using activation and scattering techniques at Triangle Universities Nuclear Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Hutcheson, A. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States)]. E-mail: hutch@tunl.duke.edu; Angell, C.T. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Becker, J.A. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Boswell, M. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Crowell, A.S. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Dashdorj, D. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Fallin, B. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Fotiades, N. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Howell, C.R.; Karwowski, H.J.; Kelley, J.H.; Kiser, M. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Macri, R.A. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Nelson, R.O. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Pedroni, R.S. [NC A and T State University, 1601 East Market Street, Greensboro, NC 27411 (United States); Tonchev, A.P.; Tornow, W. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Vieira, D.J. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Weisel, G.J. [Penn State Altoona, 3000 Ivyside Park, Altoona, PA 16601 (United States); Wilhelmy, J.B. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States)

    2007-08-15

    In support of the Stewardship Science Academic Alliances initiative, an experimental program has been developed at Triangle Universities Nuclear Laboratory (TUNL) to measure (n,xn) cross-sections with both in-beam and activation techniques with the goal of improving the partial cross-section database for the NNSA Stockpile Stewardship Program. First experimental efforts include excitation function measurements on {sup 235,238}U and {sup 241}Am using pulsed and monoenergetic neutron beams with E {sub n} = 5-15 MeV. Neutron-induced partial cross-sections were measured by detecting prompt {gamma} rays from the residual nuclei using various combinations of clover and planar HPGe detectors in the TUNL shielded neutron source area. Complimentary activation measurements using DC neutron beams have also been performed in open geometry in our second target area. The neutron-induced activities were measured in the TUNL low-background counting area. In this presentation, we include detailed information about the irradiation procedures and facilities and preliminary data on first measurements using this capability.

  20. Monte Carlo simulation of the nuclear-electromagnetic cascade development and the energy response of ionization spectrometers

    Science.gov (United States)

    Jones, W. V.

    1973-01-01

    Modifications to the basic computer program for performing the simulations are reported. The major changes include: (1) extension of the calculations to include the development of cascades initiated by heavy nuclei, (2) improved treatment of the nuclear disintegrations which occur during the interactions of hadrons in heavy absorbers, (3) incorporation of accurate multi-pion final-state cross sections for various interactions at accelerator energies, (4) restructuring of the program logic so that calculations can be made for sandwich-type detectors, and (5) logic modifications related to execution of the program.

  1. Effects of weak, low-frequency pulsed electromagnetic fields (BEMER type) on gene expression of human mesenchymal stem cells and chondrocytes: an in vitro study.

    Science.gov (United States)

    Walther, Markus; Mayer, Florian; Kafka, Wolf; Schütze, Norbert

    2007-01-01

    In vitro effects of electromagnetic fields appear to be related to the type of electromagnetic field applied. Previously, we showed that human osteoblasts display effects of BEMER type electromagnetic field (BTEMF) on gene regulation. Here, we analyze effects of BTEMF on gene expression in human mesenchymal stem cells and chondrocytes. Primary mesenchymal stem cells from bone marrow and the chondrocyte cell line C28I2 were stimulated 5 times at 12-h intervals for 8 min each with BTEMF. RNA from treated and control cells was analyzed for gene expression using the affymetrix chip HG-U133A. A limited number of regulated gene products from both cell types mainly affect cell metabolism and cell matrix structure. There was no increased expression of cancer-related genes. RT-PCR analysis of selected transcripts partly confirmed array data. Results indicate that BTEMF in human mesenchymal stem cells and chondrocytes provide the first indications to understanding therapeutic effects achieved with BTEMF stimulation.

  2. Giant electromagnetic vortex and MeV monoenergetic electrons generated by short laser pulses in underdense plasma near quarter critical density region.

    Science.gov (United States)

    Zhidkov, Alexei; Nemoto, Koshichi; Nayuki, Takuya; Oishi, Yuji; Fuji, Takashi

    2007-07-01

    Very efficient generation of monoenergetic, about 1MeV , electrons from underdense plasma with its electron density close to the critical, when irradiated by an intense femtosecond laser pulse, is found via two dimensional particle-in-cell simulation. The stimulated Raman scattering of a laser pulse with frequency omega300 keV .

  3. Electromagnetic compatibility. General presentation; Comptabilite electromagnetique. Presentation generale

    Energy Technology Data Exchange (ETDEWEB)

    Champiot, G.G. [Electricite de France (EDF), 75 - Paris (France)

    2000-02-01

    The electromagnetic environment has become an important parameter to take into account in any industrial project involving electronic systems. Four factors can conjugate to increase the problems of electromagnetic disturbances: the instrumentation and control systems which use very low voltage electronic components, the development of fast high-power electronic switching systems (thyristors etc..), the more and more frequent association of disturbing apparatuses and sensible equipments in the same integrated devices, and the sensitiveness of data processing systems. This introductory paper aims at building a general philosophy for the mastery of these phenomena: 1 - the aim of electromagnetic compatibility: notion, analysis, reduction of the problem to essentials; 2 - sources of electromagnetic disturbances: lightning, aurora borealis, disturbances due to intentional emissions (radiofrequency radiation, conduction), disturbances due to non-intentional emissions (thermal noise, switching of inductive currents, arc welding, start-up of vehicles with internal combustion engines, power lines, driving systems, fluorescent lamps, voltage drops and short cuts, harmonics, voltage transients), electrostatic discharges, nuclear electromagnetic pulses. (J.S.)

  4. Measurement of the scintillation time spectra and pulse-shape discrimination of low-energy beta and nuclear recoils in liquid argon with DEAP-1

    CERN Document Server

    Boulay, M G; Chen, M; Golovko, V V; Harvey, P; Mathew, R; Lidgard, J J; McDonald, A B; Pasuthip, P; Pollman, T; Skensved, P; Graham, K; Hallin, A L; McKinsey, D N; Lippincott, W H; Nikkel, J; Jillings, C J; Duncan, F; Cleveland, B; Lawson, I

    2009-01-01

    The DEAP-1 low-background liquid argon detector has been used to measure scintillation pulse shapes of beta decays and nuclear recoil events and to demonstrate the feasibility of pulse-shape discrimination down to an electron-equivalent energy of 20 keVee. The relative intensities of singlet/triplet states in liquid argon have been measured as a function of energy between 15 and 500 keVee for both beta and nuclear recoils. Using a triple-coincidence tag we find the fraction of beta events that are mis-identified as nuclear recoils to be less than 6x10^{-8} between 43-86 keVee and that the discrimination parameter agrees with a simple analytic model. The discrimination measurement is currently limited by nuclear recoils induced by cosmic-ray generated neutrons, and is expected to improve by operating the detector underground at SNOLAB. The analytic model predicts a beta mis-identification fraction of 10^{-10} for an electron-equivalent energy threshold of 20 keVee. This reduction allows for a sensitive search ...

  5. Electromagnetic wave collapse in a radiation background.

    Science.gov (United States)

    Marklund, Mattias; Brodin, Gert; Stenflo, Lennart

    2003-10-17

    The nonlinear interaction, due to quantum electrodynamical (QED) effects between an electromagnetic pulse and a radiation background, is investigated by combining the methods of radiation hydrodynamics with the QED theory for photon-photon scattering. For the case of a single coherent electromagnetic pulse, we obtain a Zakharov-like system, where the radiation pressure of the pulse acts as a driver of acoustic waves in the photon gas. For a sufficiently intense pulse and/or background energy density, there is focusing and the subsequent collapse of the pulse. The relevance of our results for various astrophysical applications are discussed.

  6. Effects on structure and secretion of pituitary gland in rats after electromagnetic pulse exposure%电磁脉冲对大鼠腺垂体结构和分泌功能的影响

    Institute of Scientific and Technical Information of China (English)

    方恒虎; 曾桂英; 聂青; 康静波; 任东青; 周家兴; 李运明

    2010-01-01

    目的 探讨电磁脉冲(EMP)对大鼠腺垂体结构和分泌功能的影响.方法 SD雄性大鼠48只,随机分为辐照组和假辐照组.辐照组大鼠接受200 kV/m EMP全身辐照,于辐照后12、24、48和96 h应用光镜、电镜观察腺垂体内分泌细胞形态学的改变,放射免疫法检测大鼠血清催乳素(PRL)、生长激素(GH)、促肾上腺皮质激素(ACTH)、促甲状腺激素(TSH)和黄体生成素(LH)的含量.结果 大鼠腺垂体超微结构在EMP辐照后12 h出现改变,至48 h逐渐加重,96 h有所恢复.主要病变为细胞水肿,线粒体肿胀、空泡化和髓鞘样结构形成,高尔基体和内质网扩张,次级溶酶体出现,细胞核内异染色质边集等.大鼠血清PRL和ACTH均表现为照后12 h显著升高后恢复;GH于照后12 h显著下降后逐渐回升,48 h恢复;TSH于12 h即开始下降,24 h显著下降至最低点,96 h恢复;LH于照后24~96h明显升高.结论 EMP辐照可引起大鼠腺垂体结构和分泌功能的改变.%Objective To investigate the exposure effect of electromagnetic pulse (EMP) on the structure and secretion of pituitary gland in rats.Methods Forty-eight male SD rats were randomly divided into eight groups.Four groups were subject to the EMP exposure of 200 kV/m and the others received a sham exposure.At different time points (12,24,48 & 96 h) post-exposure,the pathological changes of pituitary gland were observed by light and transmission electron microscope.And the serum levels of prolactin (PRL),growth hormone (GH),adrenocorticotropic hormone (ACTH),thyroid stimulating hormone (TSH) and luteinizing hormone (LH) were measured dynamically by radioimmunoassay.Results At 12 h post-exposure,swollen mitochondria with cristae loss,dilatation of Golgi complex and diffusive lysosomes were found in endocrine cells of pituitary gland.The above changes became gradually worse.Mitochondrial vacuolization,the formation of myelin figures,distinct dilatation of endoplasmic reticulum

  7. Realization of the Fredkin Gate by Three Transition Pulses in a Nuclear Magnetic Resonance Quantum Information Processor

    Institute of Scientific and Technical Information of China (English)

    薛飞; 杜江峰; 石名俊; 周先意; 韩荣典; 吴季辉

    2002-01-01

    We have experimentally realized the Fredkin gate with only three transition pulses in a solution of alanine. It appears that no experimental realization of the Fredkin gate with fewer pulses has been reported yet. In addition,the simple structure of our scheme makes it easy to implement in experiments.

  8. 膝骨关节炎应用脉冲电磁场治疗的系统评价%Pulsed electromagnetic field therapy for the treatment of knee osteoarthritis:a systematic review

    Institute of Scientific and Technical Information of China (English)

    曹立颖; 姜明静; 杨声坪; 赵龙; 王建民

    2012-01-01

    目的:系统评价脉冲电磁场治疗膝骨关节炎的临床效果.方法:应用Cochrane系统评价方法计算机检索Cochrane Library(2012年第2期)、PubMed (1966~2012.2)、EMBASE(1974~2012.2)、中国生物医学数据库(CBM,1978~2012.2)、中国期刊全文数据库(CNKI,1979~2012.2)和雏普数据库(VIP,1989~2012.2),同时在Google学术搜索引擎进行检索,并追查纳入研究参考文献,收集以脉冲电磁场治疗膝骨关节炎的所有随机对照试验.根据Cochrane协作网推荐的“风险评估工具”进行偏倚风险评估,用RevMan 5.1软件进行统计学分析.结果:最终纳入5个随机对照试验,共331例患者.研究结果显示:与安慰剂相比,脉冲电磁场治疗膝骨关节炎在缓解疼痛[WMD =0.12,95%CI(-0.46,0.69)]、减少晨僵时间[WMD=0.08,95%CI( -0.05,0.21)]和改善膝关节功能[WMD=-1.16,95%CI(-4.36,2.05)]等方面差异无统计学意义.结论:脉冲电磁场治疗膝骨关节炎的疗效需更多有力的证据.由于纳入研究质量和病例数量的局限,上述结论尚需更多高质量的随机对照试验进一步验证.%Objective:To evaluate the clinical effectiveness of pulsed electromagnetic field therapy in the treatment of knee osteoarthritis. Methods: Based on the principles and methods of Cochrane systematic reviews,the authors searched the Cochrane Library (2012,2 issue),PubMed (1966 to February,2012) ,EMBASE (1974 to February,2012),Chinese Bio-medicine Database (1978 to February, 2012), China Journal Full-lext Database (1979 to February, 2012), VIP database (1989 to February, 2012) ,as well as search engine Google Scholar. Randomized controlled trials (RCTs) of pulsed electromagnetic field therapy to treat knee osteoarthritis were included. The authors assessed the quality of the included trials according to the Cochrane Handbook for Systematic Reviews of Interventions Version. The Cochrane Collaboration's software RevMan 5.1 was used for meta-analysis. Results

  9. Data acquisition and pulse generation system for nuclear magnetic resonance spectrometers on a single PC-ISA compatible board

    Science.gov (United States)

    Ambrosetti, R.; Ranieri, G. A.; Ricci, D.

    1998-08-01

    A data acquisition and pulse generation system for NMR spectrometers is described. It has been implemented on a single board for MS-DOS personal computers with an ISA standard bus interface and uses a simple architecture optimizing the integration of the hardware and software resources. The system, owing to its versatility and low cost, is particularly suitable to upgrade old pulsed NMR instruments with outdated data and control systems, for applications where expensive new cryomagnetic instruments would be inappropriate, such as in industrial control or as educational tools. The board provides two simultaneous data acquisition channels allowing 250 000 12-bit conversions per second per channel, including real-time signal averaging, and is able to produce essentially any pulse sequence on several output lines. The duration of each pulse can range from 0957-0233/9/8/024/img6s to 180 s with a minimum pulse separation of 0957-0233/9/8/024/img7s and with a resolution of 0957-0233/9/8/024/img6s. All classic NMR pulse sequences are allowed in addition to those required for self-diffusion coefficient measurements using pulsed magnetic field gradients. All functions of the system are managed by machine-language routines callable from within a VisualBASIC program. The cost of the hardware of this device is under US500.

  10. Measurement of advanced electromagnetic radiation

    OpenAIRE

    Bajlo, Darko

    2017-01-01

    For the purpose of detecting advanced electromagnetic radiation predicted by Wheeler-Feynman absorber theory for the case of incomplete absorption of retarded electromagnetic radiation, pulses in duration of 6 ns to 24 ns, wavelength from 91 cm to 200 cm where supplied to three different transmitting antennas. Detection was done with a λ/20 monopole antenna in the advanced time window at a time 2r/c before the arrival of the center of the retarded pulse. At distances ranging from 430 cm to 18...

  11. Broadband electromagnetic sensors for aircraft lightning research. [electromagnetic effects of lightning on aircraft digital equipment

    Science.gov (United States)

    Trost, T. F.; Zaepfel, K. P.

    1980-01-01

    A set of electromagnetic sensors, or electrically-small antennas, is described. The sensors are designed for installation on an F-106 research aircraft for the measurement of electric and magnetic fields and currents during a lightning strike. The electric and magnetic field sensors mount on the aircraft skin. The current sensor mounts between the nose boom and the fuselage. The sensors are all on the order of 10 cm in size and should produce up to about 100 V for the estimated lightning fields. The basic designs are the same as those developed for nuclear electromagnetic pulse studies. The most important electrical parameters of the sensors are the sensitivity, or equivalent area, and the bandwidth (or rise time). Calibration of sensors with simple geometries is reliably accomplished by a geometric analysis; all the sensors discussed possess geometries for which the sensitivities have been calculated. For the calibration of sensors with more complex geometries and for general testing of all sensors, two transmission lines were constructed to transmit known pulsed fields and currents over the sensors.

  12. Nuclear spectroscopy

    CERN Document Server

    Ajzenberg-Selove, Fay

    1960-01-01

    Nuclear Spectroscopy, Part B focuses on the ways in which experimental data may be analyzed to furnish information about nuclear parameters and nuclear models in terms of which the data are interpreted.This book discusses the elastic and inelastic potential scattering amplitudes, role of beta decay in nuclear physics, and general selection rules for electromagnetic transitions. The nuclear shell model, fundamental coupling procedure, vibrational spectra, and empirical determination of the complex potential are also covered. This publication is suitable for graduate students preparing for exper

  13. The effect of electromagnetic pulse on neuronal ultrastructure and the space learning and memory ability in rats%电磁脉冲辐射致大鼠皮层神经元超微结构损伤效应及对空间学习记忆能力的影响

    Institute of Scientific and Technical Information of China (English)

    张进; 邓斌; 徐浩; 李俊钢; 邓克强; 刘太阳生; 徐礼鲜

    2013-01-01

    目的:电磁脉冲辐射(electromagnetic pulse,EMP)可以引起中枢神经系统(CNS)损伤和神经行为学的改变.因此,研究EMP对CNS短期的生物学效应具有重要意义.方法:本文通过电子显微镜技术和Morris水迷宫技术,研究了场强为400 kV/m,脉冲为200次的EMP辐射后短时间内对大鼠皮层神经元超微结构及空间学习记忆能力的影响.结果:辐照射后6h的大鼠皮层神经元超微结构显示,神经元胞核内异染色质增多;核膜有不同程度凹陷、破损及皱缩.胞质内有明显的线粒体肿胀;胞内粗面内质网呈囊性变、脱颗粒.EMP辐射后24 h时,部分神经元出现染色质浓集、边移,甚至细胞核明显皱缩而失去结构,类似凋亡细胞特点,并有凋亡小体出现.Morris水迷宫结果显示,与正常对照组相比,EMP损伤后,大鼠逃避潜伏期明显延长(P<0.05);动物在平台象限停留时间明显缩短(P<0.01).结论:400 kV/m的EMP可引起大脑皮层神经元超微结构发生损伤,且导致实验动物空间学习记忆能力的下降.%Objective:Electromagnetic pulse (EMP) can cause central nervous system (CNS) damage and neurobehavioral disorders.To study the biological effects of EMP on CNS may have important applied value.Here we reported that the biological effects of EMP (400 kV/m for 200 pulses) on neuronal ultrastructure and the space learning and memory ability in rats.Methods:The electron microscopic technology and Morris water maze was used to observe the effect of EMP on cerebral cortex neurons.Results:Electron microscope results showed the ultrastructure of rat cortical neurons in EMP group 6 h after radiation changed markedly,characterized with nuclear membrane folds,collapses,blurred boundaries,nuclear condensation.It also showed obvious swelling of mitochondria in the cytoplasm was as spherical.Moreover,at 24 h after EMP radiation,some cellular cytoplasm concentration happened as electron density increased

  14. Communication between osteoblasts stimulated by electromagnetic fields

    Institute of Scientific and Technical Information of China (English)

    ZHANG JianBao; ZHANG XiaoJun

    2007-01-01

    Pulsed electromagnetic field can affect the proliferation of osteoblasts, but the mechanism is obscure yet. The communication between osteoblasts, isolated from calvaria bone of newborn SD rats and stimulated with the rectangular electromagnetic field of 15 Hz and 4 mT, was studied. Our results showed that the osteoblasts radiated a kind of light after they were stimulated with the electromagnetic field and it is the light that promotes the proliferation of un-stimulated osteoblasts.

  15. Electromagnetic Attraction.

    Science.gov (United States)

    Milson, James L.

    1990-01-01

    Three activities involving electromagnetism are presented. Discussed are investigations involving the construction of an electromagnet, the effect of the number of turns of wire in the magnet, and the effect of the number of batteries in the circuit. Extension activities are suggested. (CW)

  16. Using nuclear magnetic resonance and transient electromagnetics to characterise water distribution beneath an ice covered volcanic crater: the case of Sherman Crater Mt. Baker Washington.

    Science.gov (United States)

    Irons, Trevor P.; Martin, Kathryn; Finn, Carol A.; Bloss, Benjamin; Horton, Robert J.

    2014-01-01

    Surface and laboratory Nuclear Magnetic Resonance (NMR) measurements combined with transient electromagnetic (TEM) data are powerful tools for subsurface water detection. Surface NMR (sNMR) and TEM soundings, laboratory NMR, complex resistivity, and X-Ray Diffraction (XRD) analysis were all conducted to characterise the distribution of water within Sherman Crater on Mt. Baker, WA. Clay rich rocks, particularly if water saturated, can weaken volcanoes, thereby increasing the potential for catastrophic sector collapses that can lead to far-travelled, destructive debris flows. Detecting the presence and volume of shallow groundwater is critical for evaluating these landslide hazards. The TEM data identified a low resistivity layer (<10 ohm-m), under 60 m of glacial ice related to water saturated clays. The TEM struggles to resolve the presence or absence of a plausible thin layer of bulk liquid water on top of the clay. The sNMR measurements did not produce any observable signal, indicating the lack of substantial accumulated bulk water below the ice. Laboratory analysis on a sample from the crater wall that likely represented the clays beneath the ice confirmed that the controlling factor for the lack of sNMR signal was the fine-grained nature of the media. The laboratory measurements further indicated that small pores in clays detected by the XRD contain as much as 50% water, establishing an upper bound on the water content in the clay layer. Forward modelling of geologic scenarios revealed that bulk water layers as thin as ½ m between the ice and clay layer would have been detectable using sNMR. The instrumentation conditions which would allow for sNMR detection of the clay layer are investigated. Using current instrumentation the combined analysis of the TEM and sNMR data allow for valuable characterisation of the groundwater system in the crater. The sNMR is able to reduce the uncertainty of the TEM in regards to the presence of a bulk water layer, a valuable

  17. Statistical pulses generator. Application to nuclear instrumentation (1962); Generateur d'impulsions aleatoires. Application a l'instrumentation nucleaire (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Beranger, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    This report describes a random pulses generator adapted to nuclear instrumentation. After a short survey on the statistical nature of electronic signals, the different ways for generating pulses with a Poisson's time-distribution are studied. The final generator built from a gaseous thyratron in a magnetic field is then described. Several tests are indicated : counting-rate stability, Pearson's criterion, distribution of time-intervals. Applications of the generator in 'whole testing' of nuclear instrumentation are then indicated for sealers, dead time measurements, time analyzers. In this application, pulse-height spectrums have been made by Poissonian sampling of a recurrent or random low-frequency signal. (author) [French] Cette etude decrit un generateur d'impulsions aleatoires et ses applications a l'instrumentation nucleaire. Apres un bref rappel sur la nature statistique des signaux en electronique nucleaire, sont passes en revue les principaux moyens d'obtenir des impulsions distribuees en temps suivant une loi de Poisson. Le generateur utilisant un thyratron a gaz dans un champ magnetique est ensuite decrit; diverses methodes de test sont appliquees (stabilite du taux de comptage, criterium de Pearson, spectre des intervalles ds temps). Les applications du generateur a l'electronique nucleaire dans le domaine des 'essais globaux' sont indiques: test des echelles de comptage et mesure des temps morts, test des analyseurs en temps apres division du taux de comptage par une puissance de deux, test des analyseurs multicanaux en amplitude. Pour cette derniere application, on a realise des spectres d'amplitudes suivant une loi connue, par echantillonnage poissonien d'un signal basse frequence recurrent ou aleatoire. (auteur)

  18. Ultrashort Laser Pulse Phenomena

    CERN Document Server

    Diels, Jean-Claude

    2006-01-01

    Ultrashort Laser Pulse Phenomena, 2e serves as an introduction to the phenomena of ultra short laser pulses and describes how this technology can be used to examine problems in areas such as electromagnetism, optics, and quantum mechanics. Ultrashort Laser Pulse Phenomena combines theoretical backgrounds and experimental techniques and will serve as a manual on designing and constructing femtosecond (""faster than electronics"") systems or experiments from scratch. Beyond the simple optical system, the various sources of ultrashort pulses are presented, again with emphasis on the basic

  19. Microprocessor-Controlled Pulsed NQR Spectrometer for Automatic Acquisition of Zeeman Perturbed Nuclear Quadrupole Spin Echo Envelope Modulations (ZSEEM )

    Science.gov (United States)

    Reddy, Narsimha; Bhavsar, Arun; Narasimhan, P. T.

    1986-02-01

    A simple microprocessor-controlled pulsed NQR spectrometer system has been developed with the capability to acquire Zeeman perturbed spin echo envelope modulations (ZSEEM). The CPU of the system is based on the Intel Corporation 8085 A microprocessor. The performance of the spectrometer is illustrated with the presentation of ZSEEM spectra of NaClO3 and KClO3.

  20. Electromagnetic fields in biological systems

    CERN Document Server

    Lin, James C

    2016-01-01

    As wireless technology becomes more sophisticated and accessible to more users, the interactions of electromagnetic fields with biological systems have captured the interest not only of the scientific community but also the general public. Unintended or deleterious biological effects of electromagnetic fields and radiation may indicate grounds for health and safety precautions in their use. Spanning static fields to terahertz waves, Electromagnetic Fields in Biological Systems explores the range of consequences these fields have on the human body. With contributions by an array of experts, topics discussed include: Essential interactions and field coupling phenomena, highlighting their importance in research on biological effects and in scientific, industrial, and medical applications Electric field interactions in cells, focusing on ultrashort, pulsed high-intensity fields The effect of exposure to naturally occurring and human-made static, low-frequency, and pulsed magnetic fields in biological systems Dosi...

  1. Electromagnetic fasteners

    Science.gov (United States)

    Crane, Randolph W.; Marts, Donna J.

    1994-01-01

    An electromagnetic fastener for manipulating objects in space uses the matic attraction of various metals. An end effector is attached to a robotic manipulating system having an electromagnet such that when current is supplied to the electromagnet, the object is drawn and affixed to the end effector, and when the current is withheld, the object is released. The object to be manipulated includes a multiplicity of ferromagnetic patches at various locations to provide multiple areas for the effector on the manipulator to become affixed to the object. The ferromagnetic patches are sized relative to the object's geometry and mass.

  2. Design of the device applying pulsed electromagnetic field in bone cell culture%脉冲电磁场辅助骨细胞培养装置的研制

    Institute of Scientific and Technical Information of China (English)

    谢小波; 庞丽云; 崔红岩; 李小红; 屈承端; 陈先农; 胡勇

    2008-01-01

    Objective A pulsed electromagnetic fields(PEMF) device with adjustable parameters designed for bone cell culture was designed according to the principle of pulsed electromagnetic fields as an effective physical factor to regulate the growth of bone cells. Functions of hardware and software were introduced as well as the design of the stimulating board. Method Based on previous research result, the device was designed to generate electromag- netic pulse with intensity of 4-6 mT and frequency of 8 Hz. The stimulating board was designed according to the size of cell culture plate. Up to six plates are allowed to be placed on the board simultaneously. Magnetic material was in- troduced to assure the uniform magnetic field. Results Functions of the device were tested and designed parameters were proved to be accomplished. The electromagnetic field generated on the surface of the stimulating board was uni- form. Conclusion All parameters designed are accomplished and the magnetic field detected on the surface of the board is uniform and ready be used as a physical factor in the up-coming experiment of bone cell culture.%目的 根据脉冲电磁场对骨细胞的作用机制,设计了能够产生均匀磁场、参数可调的脉冲电磁场发生装置和磁场作用板;叙述了实验装置的硬件构成、软件控制功能以及磁场作用板的设计,并通过试验测试,观察记录了在未加入磁性材料和加入磁性材料后磁场的分布情况.方法 设计了强度为4~6 mT、频率8 Hz的参数可调的脉冲电磁场发生装置和专用的适合细胞培养的磁场作用装置,并对产生的磁场进行了实验测定.结果 实验装置运行时,对各参数检测表明,实验装置满足设计的要求:在加入磁性材料后,磁场作用表面的磁场分布均匀.结论 实验装置满足设计要求,可为进一步进行骨细胞培养提供可靠的实验手段.

  3. Nuclear physics with advanced brilliant gamma beams at ELI-NP

    Science.gov (United States)

    Ur, Călin A.; Filipescu, Dan; Gheorghe, Ioana; Iancu, Violeta; Suliman, Gabriel; Teşileanu, Ovidiu

    2016-01-01

    The Extreme Light Infrastructure - Nuclear Physics facility is dedicated to nuclear physics studies with the use of extreme electromagnetic radiation. One of the main research system to be installed and operated in the facility is an outstanding high brilliance gamma beam system. The Gamma Beam System of ELI-NP will produce intense, quasi-monochromatic gamma beams via inverse Compton scattering of short laser pulses on relativistic electron beam pulses. The gamma beams available at ELI-NP will allow for the performance of photo-nuclear reactions aiming to reveal the intimate structure of the atomic nucleus. Nuclear Resonance Fluorescence, photo-fission, photo-disintegration reactions above the particle threshold will be used to study the dipole response of nuclei, the structure of the Pygmy resonances, nuclear processes relevant for astrophysics, production and study of exotic neutron-rich nuclei.

  4. Nuclear physics with advanced brilliant gamma beams at ELI–NP

    Directory of Open Access Journals (Sweden)

    Ur Călin A.

    2016-01-01

    Full Text Available The Extreme Light Infrastructure - Nuclear Physics facility is dedicated to nuclear physics studies with the use of extreme electromagnetic radiation. One of the main research system to be installed and operated in the facility is an outstanding high brilliance gamma beam system. The Gamma Beam System of ELI–NP will produce intense, quasi–monochromatic gamma beams via inverse Compton scattering of short laser pulses on relativistic electron beam pulses. The gamma beams available at ELI–NP will allow for the performance of photo-nuclear reactions aiming to reveal the intimate structure of the atomic nucleus. Nuclear Resonance Fluorescence, photo-fission, photo-disintegration reactions above the particle threshold will be used to study the dipole response of nuclei, the structure of the Pygmy resonances, nuclear processes relevant for astrophysics, production and study of exotic neutron–rich nuclei.

  5. 脉冲电磁场对家猪淋巴细胞的细胞遗传学效应%Cytogenetic Effects of Pulsing Electromagnetic Field on Domestic Pig Lymphocytes in Vitro

    Institute of Scientific and Technical Information of China (English)

    邹方东; 徐柳; 王子淑; 王喜忠

    2001-01-01

    以家猪外周血淋巴细胞为材料,研究了脉冲电磁场(pulsing electromagnetic fields,简称PEMFs)对细胞的遗传学效应。实验发现,100和200 kHz的PEMFs对家猪的淋巴细胞照射培养12、24、48 h后,染色体畸变(包括非整倍体、染色体断裂等)频率明显高于对照组(P<0.05)。其中,56%的染色体或染色单体断裂和42%的间隙发生在家猪常见染色体脆性位点部位。同时,经100 kHz和200 kHz的PEMFs照射48 h后,淋巴细胞姐妹染色单体交换(SCE)频率也明显高于对照组(P<0.05)。实验结果表明,PEMFs能诱导DNA损伤和染色体畸变。%The effects of pulsing electromagnetic fields (PEMFs) on cells are very important subjects in the field of bioelectromagnetics. In this experiment,the cytogenetic effects of PEMF on domestic pig lymphocytes were tested in vitro. Pig lymphocytes in RPMI 1640 medium were exposed to PEMFs of 100 kHz and 200 kHz for 12,24 and 48 hours. Chromosomal aberrations (aneuploidy,breaks,gaps,et al.) were significantly increased in exposed cultures,and of these aberrations,56% chromosomal or chromatid breaks and 42% gaps induced by PEMFs were the points of pig chromosomal fragile sites.The baseline frequency of sister-chromatid exchange (SCE) increased after exposing lymphocytes continuously to PEMFs of 100 kHz and 200 kHz for 48 hours. These results suggested that the exposure to PEMFs might induce a type of DNA lesion and chromosomal aberrations.

  6. Engineering electromagnetics

    CERN Document Server

    Thomas, David T; Hartnett, James P; Hughes, William F

    1973-01-01

    The applications involving electromagnetic fields are so pervasive that it is difficult to estimate their contribution to the industrial output: generation of electricity, power transmission lines, electric motors, actuators, relays, radio, TV and microwave transmission and reception, magnetic storage, and even the mundane little magnet used to hold a paper note on the refrigerator are all electromagnetic in nature. One would be hard pressed to find a device that works without relaying on any electromagnetic principle or effect. This text provides a good theoretical understanding of the electromagnetic field equations but also treats a large number of applications. In fact, no topic is presented unless it is directly applicable to engineering design or unless it is needed for the understanding of another topic. In electrostatics, for example, the text includes discussions of photocopying, ink-jet printing, electrostatic separation and deposition, sandpaper production, paint spraying, and powder coating. In ma...

  7. Electromagnetic Fields

    Science.gov (United States)

    ... causes cancer. Some people worry that wireless and cellular phones cause cancer or other health problems. The phones do give off radio-frequency energy (RF), a form of electromagnetic radiation. So far, scientific evidence has not found a ...

  8. Electromagnetic Railgun

    Science.gov (United States)

    2012-03-01

    DISTRIBUTION STATEMENT A: Approved for Public Release Electromagnetic Railgun ASNE Combat System Symposium 26-29 March 2012 CAPT Mike...4. TITLE AND SUBTITLE Electromagnetic Railgun 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER...Defense 3/29/2012 Slide 5 Distribution A Naval Railgun – Key Elements Capacitors or Rotating Machines Ship Integration Launcher Projectile

  9. Electromagnetic Landscape

    DEFF Research Database (Denmark)

    Cermak, Daniel; Okutsu, Ayaka; Jørgensen, Stina Marie Hasse

    2015-01-01

    Daniel Cermak-Sassenrath, Ayaka Okutsu, Stina Hasse. Electromagnetic Landscape - In-between Signal, Noise and Environment. Installation and artist talk. 21th International Symposium on Electronic Art (ISEA) 2015, Vancouver, CAN, Aug 14-18, 2015.......Daniel Cermak-Sassenrath, Ayaka Okutsu, Stina Hasse. Electromagnetic Landscape - In-between Signal, Noise and Environment. Installation and artist talk. 21th International Symposium on Electronic Art (ISEA) 2015, Vancouver, CAN, Aug 14-18, 2015....

  10. Mixture diffusion of adsorbed organic compounds in metal-organic frameworks as studied by magic-angle spinning pulsed-field gradient nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Gratz, Marcel; Hertel, Stefan; Wehring, Markus; Stallmach, Frank [Faculty of Physics and Earth Science, University of Leipzig, Linnestrasse 5, 04103 Leipzig (Germany); Galvosas, Petrik, E-mail: petrik.galvosas@vuw.ac.nz [MacDiarmid Institute for Advanced Materials and Nanotechnology, SCPS, Victoria University of Wellington, 6012 Wellington (New Zealand)

    2011-04-15

    The magic-angle spinning (MAS) and pulsed-field gradient nuclear magnetic resonance (PFG NMR) techniques have been combined using a commercially available microimaging system providing a gradient in the magic-angle direction of up to {+-}2.6 T m{sup -1}, together with a narrow bore MAS probe. By narrowing the spectral linewidths, detection of the single and mixed molecular species adsorbed in porous material and their respective mobilities becomes possible. Here, we report on protocols for MAS PFG NMR measurements, new methods for the indispensable sample alignment along the MAS rotational axis and gradient direction and first experimental results of diffusion studies on n-hexane and benzene adsorbed in the metal-organic framework MOF-5.

  11. Model of the motion of a charged particle into a plasma during the interaction of an electromagnetic pulse elliptically polarized propagating in the direction of a static and homogeneous magnetic field; Modelo del movimiento de una particula cargada en un plasma durante la interaccion de un pulso electromagnetico elipticamente polarizado propagandose en la direccion de un campo magnetico estatico y homogeneo

    Energy Technology Data Exchange (ETDEWEB)

    Gomez R, F. [UAEM, A.P. 2-139, 50000 Toluca, Estado de Mexico (Mexico); Ondarza R, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

    An analytical model for the description of the movement of a charged particle in the interaction of an electromagnetic pulse elliptically polarized propagating along of a static and homogeneous external magnetic field in a plasma starting from the force equation is presented. The method allows to express the solution in terms of the invariant phase, obtaining differential equations for the trajectory of the accelerated particle by means of an electromagnetic pulse of arbitrary amplitude and modulated by an encircling Gaussian. The numerical solutions reported in this work can find varied applications, for example in the physics of the interaction laser-plasma, in the acceleration of particles, in hot plasma and in radiative effects. (Author)

  12. Motion model for a charged particle in a plasma during the interaction of an electromagnetic pulse elliptically polarized propagating in the direction of a static and homogeneous magnetic field; Modelo del movimiento de una particula cargada en un plasma durante la interaccion de un pulso electromagnetico elipticamente polarizado propagandose en la direccion de un campo magnetico estatico y homogeneo

    Energy Technology Data Exchange (ETDEWEB)

    Gomez R, F. [UAEM, Facultad de Ciencias, 50000 Toluca, Estado de Mexico (Mexico); Ondarza R, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

    An analytic model is presented for the description of the motion of a charged particle in the interaction of an elliptically electromagnetic pulse polarized propagating along a static and homogeneous external magnetic field in a plasma starting from the force equation. The method allows to express the solution in terms of the invariant phase, obtaining differential equations for the trajectory of the accelerated particle by means of an electromagnetic pulse of arbitrary and modulated width by an encircling Gaussian. The numerical solutions reported in this work can find varied applications, for example in the physics of the interaction laser-plasma, in the acceleration of particles, in hot plasma and in radioactive effects. (Author)

  13. Combination of Local Transplantation of In Vitro Bone-marrow Stromal Cells and Pulsed Electromagnetic Fields Accelerate Functional Recovery of Transected Sciatic Nerve Regeneration: A Novel Approach in Transected Nerve Repair.

    Science.gov (United States)

    Mohammadi, Rahim; Mahmoodzadeh, Sirvan

    2015-01-01

    Effect of combination of undifferentiated bone marrow stromal cells (BMSCs) and pulsed electromagnetic fields (PEMF) on transected sciatic nerve regeneration was assessed in rats. A 10 mm nerve segment was excised and a vein graft was used to bridge the gap. Twenty microliter undifferentiated BMSCs (2× 107 cells /mL) were administered into the graft inBMSC group with no exposure to PEMF. In BMSC/PEMF group the whole body was exposed to PEMF (0.3 mT, 2Hz) for 4h/day within 1-5 days. In PEMF group the transected nerve was bridged and phosphate buffered saline was administered into the graft. In authograft group (AUTO), the transected nervesegments were reimplanted reversely and the whole body was exposed to PEMF. The regenerated nerve fibers were studied within 12 weeks after surgery. Behavioral, functional, electrophysiological, biomechanical, gastrocnemius muscle mass findings, morphometric indices and immuonohistochemical reactions confirmed faster recovery of regenerated axons in BMSC/PEMF group compared to those in the other groups (Pelectromagnetic fields could be considered as an effective, safe and tolerable treatment for peripheral nerve repair in clinical practice.

  14. Response Analysis on Electrical Pulses under Severe Nuclear Accident Temperature Conditions Using an Abnormal Signal Simulation Analysis Module

    OpenAIRE

    Kil-Mo Koo; Jin-Ho Song; Sang-Baik Kim; Kwang-Il Ahn; Won-Pil Baek; Kil-Nam Oh; Gyu-Tae Kim

    2012-01-01

    Unlike design basis accidents, some inherent uncertainties of the reliability of instrumentations are expected while subjected to harsh environments (e.g., high temperature and pressure, high humidity, and high radioactivity) occurring in severe nuclear accident conditions. Even under such conditions, an electrical signal should be within its expected range so that some mitigating actions can be taken based on the signal in the control room. For example, an industrial process control standard...

  15. Influence of shock wave pressure amplitude and pulse repetition frequency on the lifespan, size and number of transient cavities in the field of an electromagnetic lithotripter

    Science.gov (United States)

    Huber, Peter; Jöchle, Knut; Debus, Jürgen

    1998-10-01

    Monitoring the generation of cavitation is of great interest for diagnostic and therapeutic use of ultrasound in medicine, since cavitation is considered to play a major role in nonthermal ultrasound interactions with tissue. Important parameters are the number of cavitation events and the energy released during the bubble collapse. This energy is correlated to the maximum bubble radius which is related to the cavitation lifespan. The aim of this study was therefore to investigate the influence of the acoustic pressure amplitude and the pulse repetition frequency (PRF) in the field of a lithotripter (Lithostar, Siemens) on the number, size and lifespan of transient cavitation bubbles in water. We used scattered laser light recorded by a photodiode and stroboscopic photographs to monitor the cavitation activity. We found that PRF (range 0.5-5 Hz) had no influence on the cavitation bubble lifespan and size, whereas lifespan and size increased with the acoustic pressure amplitude. In contrast, the number of cavitation events strongly increased with PRF, whereas the pressure amplitude had no significant influence on the number of cavitation events. Thus, by varying the pressure amplitude and PRF, it might be possible to deliver a defined relative number of cavitations at a defined relative energy level in a defined volume. This seems to be relevant to further studies that address the biological effects of transient cavitation occurring in the fields of lithotripters.

  16. ELECTROMAGNETIC RELEASE MECHANISM

    Science.gov (United States)

    Michelson, C.

    1960-09-13

    An electromagnetic release mechanism is offered that may be used, for example, for supporting a safety rod for a nuclear reactor. The release mechanism is designed to have a large excess holding force and a rapid, uniform, and dependable release. The fast release is accomplished by providing the electromagnet with slotttd polts separated by an insulating potting resin, and by constructing the poles with a ferro-nickel alloy. The combination of these two features materially reduces the eddy current power density whenever the magnetic field changes during a release operation. In addition to these features, the design of the armature is such as to provide ready entrance of fluid into any void that might tend to form during release of the armature. This also improves the release time for the mechanism. The large holding force for the mechanism is accomplished by providing a small, selected, uniform air gap between the inner pole piece and the armature.

  17. Development of graded Ni-YSZ composite coating on Alloy 690 by Pulsed Laser Deposition technique to reduce hazardous metallic nuclear waste inventory.

    Science.gov (United States)

    Sengupta, Pranesh; Rogalla, Detlef; Becker, Hans Werner; Dey, Gautam Kumar; Chakraborty, Sumit

    2011-08-15

    Alloy 690 based 'nuclear waste vitrification furnace' components degrade prematurely due to molten glass-alloy interactions at high temperatures and thereby increase the volume of metallic nuclear waste. In order to reduce the waste inventory, compositionally graded Ni-YSZ (Y(2)O(3) stabilized ZrO(2)) composite coating has been developed on Alloy 690 using Pulsed Laser Deposition technique. Five different thin-films starting with Ni80YSZ20 (Ni 80 wt%+YSZ 20 wt%), through Ni60YSZ40 (Ni 60 wt%+YSZ 40 wt%), Ni40YSZ60 (Ni 40 wt%+YSZ 60 wt%), Ni20YSZ80 (Ni 20 wt%+YSZ 80 wt%) and Ni0YSZ100 (Ni 0 wt%+YSZ 100 wt%), were deposited successively on Alloy 690 coupons. Detailed analyses of the thin-films identify them as homogeneous, uniform, pore free and crystalline in nature. A comparative study of coated and uncoated Alloy 690 coupons, exposed to sodium borosilicate melt at 1000°C for 1-6h suggests that the graded composite coating could substantially reduced the chemical interactions between Alloy 690 and borosilicate melt.

  18. $\\Delta$-N Electromagnetic Transition

    CERN Document Server

    Loan, M

    1999-01-01

    The EM ratio for a free Delta electromagnetic transition is discussed within the frame work of nonrelativistic approach. Such an approach gives a good account of data for a free Delta but is less important for an intrinsically relativistic nuclear many body problem.

  19. Heat Radiators for Electromagnetic Pumps

    Science.gov (United States)

    Campana, R. J.

    1986-01-01

    Report proposes use of carbon/carbon composite radiators in electromagnetic coolant pumps of nuclear reactors on spacecraft. Carbon/carbon composite materials function well at temperatures in excess of 2,200 K. Aluminum has melting temperature of only 880 K.

  20. Design Study for Pulsed Proton Beam Generation

    Directory of Open Access Journals (Sweden)

    Han-Sung Kim

    2016-02-01

    Full Text Available Fast neutrons with a broad energy spectrum, with which it is possible to evaluate nuclear data for various research fields such as medical applications and the development of fusion reactors, can be generated by irradiating proton beams on target materials such as beryllium. To generate short-pulse proton beam, we adopted a deflector and slit system. In a simple deflector with slit system, most of the proton beam is blocked by the slit, especially when the beam pulse width is short. Therefore, the available beam current is very low, which results in low neutron flux. In this study, we proposed beam modulation using a buncher cavity to increase the available beam current. The ideal field pattern for the buncher cavity is sawtooth. To make the field pattern similar to a sawtooth waveform, a multiharmonic buncher was adopted. The design process for the multiharmonic buncher includes a beam dynamics calculation and three-dimensional electromagnetic simulation. In addition to the system design for pulsed proton generation, a test bench with a microwave ion source is under preparation to test the performance of the system. The design study results concerning the pulsed proton beam generation and the test bench preparation with some preliminary test results are presented in this paper.

  1. Pulse joining cartridges

    Energy Technology Data Exchange (ETDEWEB)

    Golovashchenko, Sergey Fedorovich; Bonnen, John Joseph Francis

    2016-08-23

    A pulsed joining tool includes a tool body that defines a cavity that receives an inner tubular member and an outer tubular member and a pulse joining cartridge. The tubular members are nested together with the cartridge being disposed around the outer tubular member. The cartridge includes a conductor, such as a wire or foil, that extends around the outer tubular member and is insulated to separate a supply segment from a return segment. A source of stored electrical energy is discharged through the conductor to join the tubular members with an electromagnetic force pulse.

  2. Electromagnetic Dissociation of Target Nuclei by $^{208}$Pb Projectiles

    CERN Multimedia

    Petridis, A; Wohn, F K

    2002-01-01

    % NA53 \\\\ \\\\ The purpose of this experiment is to study the process of electromagnetic dissociation (ED) that occurs at impact parameters large enough so that there is no nuclear interaction. In these cases strong electromagnetic fields are produced for a short time at the nucleus. For large charges and ultrarelativistic energies, the intense electromagnetic pulse produces cross-sections much larger than the total hadronic cross-section. These effects place significant constraints on the storage times of the heavy ion beams planned for RHIC and LHC.\\\\ \\\\In this experiment we measure the cross-sections for the one- and two-neutron removal processes resulting from the interaction of 160 and 40~GeV/nucleon Pb beams on Au and Co targets. Thin Au targets were bombarded in the beam line of the NA50 experiment. Gamma rays from the residual nuclides produced in the bombardment were measured to determine the saturation activities of $^{196}$Au and $^{195}$Au resulting from ED of the Au target. This along with cross-se...

  3. Pulse on Pulse

    DEFF Research Database (Denmark)

    Schmidt, Ulrik; Carlson, Merete

    2012-01-01

    Pulse on Pulse” investigates the relation between signifying processes and non-signifying material dynamism in the installation Pulse Room (2006-) by Mexican Canadian artist Rafael Lozano-Hemmer. In Pulse Room the sense of pulse is ambiguous. Biorhythms are transmitted from the pulsing energy...... and pulsating ‘room’. Hence, the visitors in Pulse Room are invited into a complex scenario that continuously oscillates between various aspects of signification (the light bulbs representing individual lives; the pulse itself as the symbolic ‘rhythm of life’) and instants of pure material processuality...... a multilayered sense of time and space that is central to the sensory experience of Pulse Room as a whole. Pulse Room is, at the very same time, an anthropomorfized archive of a past intimacy and an all-encompassing immersive environment modulating continuously in real space-time....

  4. Electromagnetic Landscape

    DEFF Research Database (Denmark)

    Cermak, Daniel; Okutsu, Ayaka; Hasse, Stina

    2015-01-01

    Electromagnetic Landscape demonstrates in direct, tangible and immediate ways effects of the disruption of the familiar. An ubiquitous technological medium, FM radio, is turned into an alien and unfamiliar one. Audience participation, the environment, radio signals and noise create a site...

  5. All-Electromagnetic Control of Broadband Quantum Excitations using Gradient Photon Echoes

    CERN Document Server

    Liao, Wen-Te; Pálffy, Adriana

    2014-01-01

    A broadband quantum echo effect in a three level $\\varLambda$-type system interacting with two laser fields is investigated theoretically. Inspired by the emerging field of nuclear quantum optics which typically deals with very narrow resonances, we consider broadband probe pulses that couple to the system in the presence of an inhomogeneous control field. We show that such a setup provides an all-electromagnetic-field solution to implement high bandwidth photon echoes, which are easy to control, store and shape on a short time scale and therefore may speed up future photonic information processing. The time compression of the echo signal and possible applications for quantum memories are discussed.

  6. 电磁脉冲对大鼠心脏和肝脏损伤及修复的影响%Effects of electromagnetic pulses on the heart and liver of rat and subsequent self-recovery

    Institute of Scientific and Technical Information of China (English)

    林锦文; 刘合; 张杰; 齐红星; 沈晓钦; 陈树德; 王向晖

    2015-01-01

    采用宽频谱电磁脉冲(场强为110 kV/m和140 kV/m,脉冲个数为5个和100个,脉冲前沿20 ns,脉宽200 ns)辐照雄性大鼠,分别于受照后6 h、1 d、3 d、7 d、10 d和15 d取样,通过全自动生化分析仪和酶联免疫吸附试验(Elisa)法检测心、肝功能有关的血清生化指标(谷丙转氨酶ALT和谷草转氨酶AST),以及肝脏和心脏组织细胞凋亡相关蛋白(促凋亡蛋白Bax和抑凋亡蛋白Bcl-2)水平随辐照后时间而产生的变化,并表征大鼠心脏与肝脏组织受到的损伤以及随后的自我修复情况。结果表明:宽频谱电磁脉冲辐照后6 h大鼠肝功能相关血清ALT和AST明显降低,肝脏组织中Bax和Bcl-2表达水平均显著性升高,照后ALT、AST和Bax于1 d后、Bcl-2于7 d后恢复到Sham组水平,说明辐照对大鼠肝脏组织产生了早期损伤效应并启动自我修复功能,1 d后得以修复;未观察到大鼠心脏组织的自我修复情况,推测辐照对其无显著性的早期损伤效应。%ABSTRACTThe influences of W-EMP (Wide-band electromagnetic pulse) exposure (field strength: 110 kV/m or 140 kV/m, pulse number: 5 or 100, pulse leading edge width: 20 ns, and the pulse width: 200 ns) on the liver and heart tissue of male rat, as well as subsequent recovery behavior, were investigated. At 6 h, 1 d, 3 d, 7 d, and 10 d separately from after-exposure, samples were collected for following assays to characterize the early damage and self-recovery of tissues: serum biochemical indexes (ALT and AST) related to heart and liver were detected by automatic biochemical analyzer, and the content of apoptosis-related proteins (Bax and Bcl-2) in both liver and heart was measured by Enzyme linked immunosorbent assay (Elisa). The results showed that significantly decreased levels of serum biochemical indicators (ALT and AST) and elevated apoptosis-related proteins (Bax and Bcl-2) (p<0.05) in liver were detected at 6 h of after

  7. Cooperative emission from nuclei: The collective Lamb shift and electromagnetically induced transparency

    Energy Technology Data Exchange (ETDEWEB)

    Roehlsberger, R. [Deutsches Elektronen Synchrotron DESY, Notkestr. 85, 22607 Hamburg (Germany)

    2013-02-15

    The narrow nuclear resonances of Moessbauer isotopes constitute almost ideal two-level systems to study cooperative effects in the interaction of x-rays with matter. Embedding an ensemble of resonant Moessbauer nuclei into a planar cavity facilitates the excitation of superradiant oscillatory eigenmodes via pulses of synchrotron radiation. These modes exhibit a large collective Lamb shift that can be controlled via the excitation conditions and the cavity geometry. Cooperative emission in connection with the radiative coupling of two resonant ensembles in a cavity leads to electromagnetically induced transparency (EIT). This contribution gives a review on cooperative effects in nuclear resonant scattering of synchrotron radiation. Special emphasis is given to the basic principles of recent experiments that led to the observation of the collective Lamb shift and EIT with nuclear resonances in the regime of hard x-rays. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Trapped field properties of a Y–Ba–Cu–O bulk by pulsed field magnetization using a split coil inserted by iron yokes with various geometries and electromagnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, K., E-mail: t2216017@iwate-u.ac.jp [Department of Physical Science and Materials Engineering, Faculty of Science and Engineering, Iwate University, 4-3-5 Ueda, Morioka 020-8551 (Japan); Ainslie, M.D. [Bulk Superconductivity Group, Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ (United Kingdom); Fujishiro, H.; Naito, T. [Department of Physical Science and Materials Engineering, Faculty of Science and Engineering, Iwate University, 4-3-5 Ueda, Morioka 020-8551 (Japan); Shi, Y-H.; Cardwell, D.A. [Bulk Superconductivity Group, Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ (United Kingdom)

    2017-05-15

    Highlights: • The trapped field characteristics of a standard Y–Ba–Cu–O bulk magnetized by PFM was investigated using a split coil with three kinds of iron yokes inserted in the bores of coil,both experimentally and numerically. • Numerical results encourage better understanding of the role of yoke, including the typical behavior of the magnetic flux, such as a flux jump during PFM. • A higher saturation magnetic flux density of the yoke material was effective to reduce flux flow in the descending stage of the pulsed field. • A conductivity of the yoke material also acts to reduce the velocity of the flux intruding the bulk because of eddy currents that flow in the yoke that oppose the magnetization, which reduces the temperature rise in the bulk. - Abstract: We have investigated, both experimentally and numerically, the trapped field characteristics of a standard Y–Ba–Cu–O bulk of 30 mm in diameter and 14 mm in thickness magnetized by pulsed field magnetization (PFM) using a split coil, in which three kinds of iron yoke are inserted in the bore of the coil: soft iron with a flat surface, soft iron with a taper, and permendur (50Fe + 50Co alloy) with a flat surface. The highest trapped field, B{sub Tmax}, of 2.93 T was achieved at 40 K in the case of the permendur yoke, which was slightly higher than that obtained for the flat soft iron or the tapered soft iron yokes, and was much higher than 2.20 T in the case without the yoke. The insertion effect of the yoke on the trapped field characteristics was also investigated using numerical simulations. The results suggest that the saturation magnetic flux density, B{sub sat}, of the yoke acts to reduce the flux flow due to its hysteretic magnetization curve and the higher electrical conductivity, σ, of the yoke material also acts to suppress the flux increase rate. A flux jump (or flux leap) can be reproduced in the ascending stage of PFM using numerical simulation, using an assumption of relatively

  9. 低频脉冲电磁场治疗骨质疏松症疼痛的临床研究%Low frequency pulse electromagnetic field in the treatment of osteoporosis clinical study of pain

    Institute of Scientific and Technical Information of China (English)

    夏新蜀; 李小宏; 林海丹

    2014-01-01

    目的:观察低频脉冲电磁场(PEMFs)治疗骨质疏松症慢性疼痛的临床疗效。方法:20例志愿受试者均为绝经女性,具有明显骨质疏松症疼痛,4例伴有OP脆性骨折,骨密度降低程度符合WHO的OP诊断标准。采用低频脉冲电磁场,功率≤2000VA;脉冲频率1Hz至100Hz可调;磁感应强度1至50Hz区间:0至100Gs可调,51Hz至100Hz区间:0至75Gs可调。单独采用低频脉冲电磁场治疗,停用其他治疗。将治疗环移至病变部位或疼痛部位,每次治疗30至40分钟,每日一次,20至30次为一疗程。疗程结束后,进行自身前后配对T检验,对VAS、骨密度结果进行统计学处理,判断治疗效果。结果:治疗前后VAS均数为5.85、3.25,标准差1.53、0.79,T值6.50,P<0.001;骨密度治疗前后无显著性差异,T值1.33,P>0.05。结论:低频脉冲电磁场能够明显缓解OP慢性疼痛,是OP的有效物理治疗方法,无不良反应发生。骨密度变化无显著性差异与观察时间短、骨质改变慢等因素有关。%Objective: In order to study the effect of low-frequency pulsed electromagnetic field on the pain in osteoporosis. Methods: 20 postmenopausal women suffering from pain, who were diagnosed as osteoporosis according to the WHO standard, mean age was 65.2 (range 50-79), were included in this trial. These patients suffered from osteoporotic pain at least 6 months, and the mean course of disease was 5.12 years. 4 patients had osteoporotic fracture. All patients only received the low-frequency pulsed electromagnetic field therapy with ZH-21 osteoporosis treatment system ( Power ≤ 2000VA; Pulsed Frequency:1-100Hz;Magnetic Induction: 0-100Gs with pulsed frequency 1-50Hz, 0-75Gs with pulsed frequency 51-100Hz ). A total of 20-30 manage-ments, with 30-40 min at a time and once per day, were given to the patients. The VAS and the bone mineral density were tested in the post-therapy period compared

  10. 高频电磁脉冲处理工业循环水的频率效应实验研究%Experimental research on the frequency effects of high-frequency electromagnetic pulse on the treatment of industrial circulating water

    Institute of Scientific and Technical Information of China (English)

    陈加鹏; 熊兰; 胡国辉; 杨子康; 苗雪飞; 伍懿美

    2014-01-01

    To study the scale inhibi tion m echanism of circulating water system with high-frequency pulse electric power sources,a set of small-scale and high-frequency electromagnetic circulating water treatment system has been researched. Taking pulse frequency as variable,six groups of scale inhibition experiments have been done. The alter-nation trends of calcium ions solubility with different pulse frequencies are analyzed ,and the corresponding micro-mechanism of scale samples under scanning electronic microscopic is observed. It is found that with different pulse frequencies,the changes of calcium ions solubility of the treatment group compared with the blank control group ap-pears to be three kinds of trends:higher,lower and closer. The scale inhibition mechanism of high-frequency electro-magnetic pulse are as follows:the effects of pulse frequency on water are both scale inhibiting and scale promoting. When electromagnetic frequency and hydrogen bond resonance frequency are closer ,the scale inhibiting plays a leading role,while electromagnetic frequency and gritty particles resonance frequency are closer,the scale promoting plays a leading role. Generally speaking,both kinds of effects exist at the same time.%为研究高频脉冲电源对循环水系统的阻垢机理,采用一套小型高频电磁循环水处理系统,以脉冲频率为变量,完成6组阻垢实验,分析不同脉冲频率下钙离子溶度的变化趋势,并观察扫描电镜下相应的垢样微观结构。结果发现,在不同脉冲频率下,处理组的钙离子溶度变化相比空白组呈现高、低、接近这3种趋势。高频电磁脉冲的阻垢机理:脉冲频率对水体的作用既阻碍结垢又促进结垢,当电磁频率与氢键共振频率接近时,阻碍结垢起主导作用;当电磁频率与杂质粒子共振频率接近时,促进结垢起主导作用,且两种作用一般同时存在。

  11. ResearchAdvances in the Biological Effects of Pulsed Electromagnetic Fields on Osteogenesis%脉冲电磁场成骨生物学效应的研究进展

    Institute of Scientific and Technical Information of China (English)

    卓祥龙(综述); 胡建中(审校)

    2014-01-01

    近年来,脉冲电磁场( PEMFs)在分子、细胞、组织和器官水平对成骨的影响已被广泛研究。PEMFs通过影响细胞分子信号转导、调节相关基因、蛋白合成以及各种细胞因子分泌来调节细胞增殖和分化,抑制骨吸收,促进新骨形成和骨折愈合,并被广泛用于临床上治疗骨折、骨折延迟愈合、骨不连以及脊柱融合。此外,PEMFs还能够提高与组织工程支架联合培养的种子细胞活性。%In recent years,pulsed electromagnetic fields(PEMFs) has been studied extensively in osteo-genic effect at the molecular,cellular,tissue and organ levels.Here is to make a review of the effects of PEMFs on bone formation and bone resorption were reviewed.By regulating cellular,molecular signal transduc-tion,related gene expression,protein synthesis and secretion of various cytokines,PEMFs regulate cell prolifera-tion and differentiation,inhibit bone resorption,promote new bone formation and bone fracture healing ,and is widely used in the clinical treatment for bone fractures ,delayed union,nonunion,and spinal fusion.In addition, PEMFs can also improve the activities of seed cells co -cultured with tissue engineering scaffolds .

  12. Analysis on Coordination System of Fuse and Warhead of Electromagnetic Pulse Bomb With Cascaded Flux Compression%爆磁压缩电磁脉冲弹引战配合分析

    Institute of Scientific and Technical Information of China (English)

    毛超; 刘忠; 邱志明; 卢发兴

    2012-01-01

    为了提高爆磁压缩电磁脉冲弹作战使用效能,根据该弹定向辐射特点,分析了爆磁压缩电磁脉冲弹定向辐射引战配合特性,建立了电磁脉冲弹引战配合的数学模型,给出了控制电磁脉冲弹引信最佳起爆时刻的数值计算方法.通过数值优化分析,给出了弹目交会参数对定向辐射天线对准精度的影响曲线.仿真图像表明,俯仰角参数对辐射天线对准精度影响最大.研究结论可为电磁脉冲弹攻击参数的计算和战术使用提供理论依据.%To improve the operational effectiveness of electromagnetic pulse bomb(EMPB) with cascaded flux compression,the characteristics of fuse and warhead matching were analyzed based on the directed radiation property,and the coordination system of EMPB was built. Based on the coordination system, the numerical method for the optimal detonation time of the fuse was proposed. By numerical optimization, the effect of parameters of bomb encountering target on reg- istration precision of active antenna was obtained. The calculation figures show that the pitching angle is the principal factor affecting the registration precision. The numerical simulation results offer theoretic basis for setting attack parameters and tactical use of EMPB.

  13. 一种改进的核脉冲峰值甄别器%An Improved Nuclear Pulse Peak-Discriminator

    Institute of Scientific and Technical Information of China (English)

    高松松; 王颖; 司伟建; 刘云涛

    2012-01-01

    To avoid the lost or error phenomena caused by the analog-to-digital converter (ADC) conversion rate in the case of random input signals with pulse width and peak in the traditional discriminator, a CMOS peak-discriminator used in a nuclear pulse peak detector (PKD) was designed by using the differential zero-crossing comparator (DZC) to trigger the ADC to transform the peak-voltage into digital at the peak-time and trigger the circuit to reset PKD at the valley-time. The simulation results by Hspice show that the peak discriminator makes the peak detection system complete the accurate peak detection of all input signal, eliminate the restriction of ADC on conversion rate and reduce the dead time of the system.%为了避免以往峰值甄别器在输入信号脉宽、峰值均随机的情况下因ADC转换速度造成后端处理器的错记、漏记现象,利用微分过零比较器设计了一种应用于核脉冲峰值探测器的CMOS峰值甄别电路,完成了峰值时刻触发ADC进行峰值模数转换和峰谷时刻进行复位触发的功能.通过Hspice软件进行仿真,证明了采用该峰值甄别电路可以使峰值探测系统完成对输入信号峰值信息的准确检测,同时消除了对转换速度较快ADC的限制,减小了整个系统的死时间.

  14. Phase transitions and anionic dynamics of dimethylammonium hexachlorotellurate(IV) as studied by pulsed nuclear quadrupole resonance of chlorine

    Science.gov (United States)

    Ishikawa, Atsushi; Horiuchi, Keizo; Ikeda, Ryuichi; Nakamura, Daiyu

    1989-01-01

    The temperature dependence of 35Cl NQR frequencies has been reinvestigated for dimethylammonium hexachlorotellurate(IV) using an FT NQR spectrometer. A new line is observed just above the lowest-frequency line already reported for the intermediate-temperature phase. In the lowest-temperature phase, the temperature dependence is definitely determined by finding new lines. The NQR frequencies can be precisely measured even in the vicinity of the phase transitions. The temperature dependence of the nuclear quadrupole relaxation time, T1Q of 35Cl and 37Cl nuclei has also been observed. In a temperature range 64-160 K, the isotope ratio, T1Q( 37Cl)/ T1Q( 35Cl) is 1.5 for each line, suggesting that the quadrupolar relaxation arises mainly from the libration of the complex anion. Above 160 K, T1Q decreases very rapidly with increasing temperature for each line. This can be interpreted in terms of the onset of the reorientation of the anion as a whole, which is responsible for the fade-out phenomenon of the two lines occurring near 220 K. The nature of the phase transitions and the anionic dynamics are discussed in detail. Especially, the phase transition at 96 K which is rather unusual and is explained through softening of the librations and the rotational displacement of the anions successively operated.

  15. Computational Electromagnetics

    CERN Document Server

    Rylander, Thomas; Bondeson, Anders

    2013-01-01

    Computational Electromagnetics is a young and growing discipline, expanding as a result of the steadily increasing demand for software for the design and analysis of electrical devices. This book introduces three of the most popular numerical methods for simulating electromagnetic fields: the finite difference method, the finite element method and the method of moments. In particular it focuses on how these methods are used to obtain valid approximations to the solutions of Maxwell's equations, using, for example, "staggered grids" and "edge elements." The main goal of the book is to make the reader aware of different sources of errors in numerical computations, and also to provide the tools for assessing the accuracy of numerical methods and their solutions. To reach this goal, convergence analysis, extrapolation, von Neumann stability analysis, and dispersion analysis are introduced and used frequently throughout the book. Another major goal of the book is to provide students with enough practical understan...

  16. Apparatus for processing electromagnetic radiation and method

    Science.gov (United States)

    Gatewood, George D. (Inventor)

    1983-01-01

    Measuring apparatus including a ruled member having alternate transparent and opaque zones. An optical coupler connecting the ruled member with electromagnetic radiation-conversion apparatus. The conversion apparatus may include a photomultiplier and a discriminator. Radiation impinging on the ruled member will, in part, be converted to electrical pulses which correspond to the intensity of the radiation. A method of processing electromagnetic radiation includes providing a member having alternating dark and light zones, establishing movement of the member through the beam of electromagnetic radiation with the dark zones interrupting passage of radiation through the rule, providing an optical coupler to connect a portion of the radiation with a conversion station where the radiation portion is converted into an electrical pulse which is related to the intensity of the radiation received at the conversion station. The electrical pulses may be counted and the digitized signals stored or permanently recorded to produce positional information.

  17. Engineering electromagnetics

    CERN Document Server

    Ida, Nathan

    2015-01-01

    This book provides students with a thorough theoretical understanding of electromagnetic field equations and it also treats a large number of applications. The text is a comprehensive two-semester textbook. The work treats most topics in two steps – a short, introductory chapter followed by a second chapter with in-depth extensive treatment; between 10 to 30 applications per topic; examples and exercises throughout the book; experiments, problems  and summaries.   The new edition includes: updated end of chapter problems; a new introduction to electromagnetics based on behavior of charges; a new section on units; MATLAB tools for solution of problems and demonstration of subjects; most chapters include a summary. The book is an undergraduate textbook at the Junior level, intended for required classes in electromagnetics. It is written in simple terms with all details of derivations included and all steps in solutions listed. It requires little beyond basic calculus and can be used for self-study. The weal...

  18. Electromagnetic theory for electromagnetic compatibility engineers

    CERN Document Server

    Toh, Tze-Chuen

    2013-01-01

    Engineers and scientists who develop and install electronic devices and circuits need to have a solid understanding of electromagnetic theory and the electromagnetic behavior of devices and circuits. In particular, they must be well-versed in electromagnetic compatibility, which minimizes and controls the side effects of interconnected electric devices. Designed to entice the practical engineer to explore some worthwhile mathematical methods, and to reorient the theoretical scientist to industrial applications, Electromagnetic Theory for Electromagnetic Compatibility Engineers is based on the

  19. Pulse on Pulse

    DEFF Research Database (Denmark)

    Schmidt, Ulrik; Carlson, Merete

    2012-01-01

    and pulsating ‘room’. Hence, the visitors in Pulse Room are invited into a complex scenario that continuously oscillates between various aspects of signification (the light bulbs representing individual lives; the pulse itself as the symbolic ‘rhythm of life’) and instants of pure material processuality......“Pulse on Pulse” investigates the relation between signifying processes and non-signifying material dynamism in the installation Pulse Room (2006-) by Mexican Canadian artist Rafael Lozano-Hemmer. In Pulse Room the sense of pulse is ambiguous. Biorhythms are transmitted from the pulsing energy...... of the visitor’s beating heart to the blink of a fragile light bulb, thereby transforming each light bulb into a register of individual life. But at the same time the blinking light bulbs together produce a chaotically flickering light environment composed by various layers of repetitive rhythms, a vibrant...

  20. Electromagnetic aquametry electromagnetic wave interaction with water and moist substances

    CERN Document Server

    Kupfer, Klaus

    2006-01-01

    This book covers all aspects of Electromagnetic Aquametry. It summarizes the wide area of metrology and its applications in electromagnetic sensing of moist materials. The physical properties of water in various degrees of binding interacting with electromagnetic fields is presented by model systems. The book describes measurement methods and sensors in the frequency domain, TDR-techniques for environmental problems, methods and sensors for quality assessment of biological substances, and nuclear magnetic resonance techniques. Environmental sciences, as well as civil and geoengineering, fossil fuels, food and pharmaceutical science are the main fields of application. A very wide frequency sprectrum is used for dielectric measurement methods, but the microwave range is clearly dominant. Multiparameter methods as well as methods of principal components and artificial neural networks for density independent measurements are described.