WorldWideScience

Sample records for internal shock emission

  1. Gamma-ray emission from internal shocks in novae

    Science.gov (United States)

    Martin, P.; Dubus, G.; Jean, P.; Tatischeff, V.; Dosne, C.

    2018-04-01

    Context. Gamma-ray emission at energies ≥100 MeV has been detected from nine novae using the Fermi Large Area Telescope (LAT), and can be explained by particle acceleration at shocks in these systems. Eight out of these nine objects are classical novae in which interaction of the ejecta with a tenuous circumbinary material is not expected to generate detectable gamma-ray emission. Aim. We examine whether particle acceleration at internal shocks can account for the gamma-ray emission from these novae. The shocks result from the interaction of a fast wind radiatively-driven by nuclear burning on the white dwarf with material ejected in the initial runaway stage of the nova outburst. Methods: We present a one-dimensional model for the dynamics of a forward and reverse shock system in a nova ejecta, and for the associated time-dependent particle acceleration and high-energy gamma-ray emission. Non-thermal proton and electron spectra are calculated by solving a time-dependent transport equation for particle injection, acceleration, losses, and escape from the shock region. The predicted emission is compared to LAT observations of V407 Cyg, V1324 Sco, V959 Mon, V339 Del, V1369 Cen, and V5668 Sgr. Results: The ≥100 MeV gamma-ray emission arises predominantly from particles accelerated up to 100 GeV at the reverse shock and undergoing hadronic interactions in the dense cooling layer downstream of the shock. The emission rises within days after the onset of the wind, quickly reaches a maximum, and its subsequent decrease reflects mostly the time evolution of the wind properties. Comparison to gamma-ray data points to a typical scenario where an ejecta of mass 10-5-10-4 M⊙ expands in a homologous way with a maximum velocity of 1000-2000 km s-1, followed within a day by a wind with a velocity values of which result in the majority of best-fit models having gamma-ray spectra with a high-energy turnover below 10 GeV. Our typical model is able to account for the main

  2. 30th International Symposium on Shock Waves

    CERN Document Server

    Sadot, Oren; Igra, Ozer

    2017-01-01

    These proceedings collect the papers presented at the 30th International Symposium on Shock Waves (ISSW30), which was held in Tel-Aviv Israel from July 19 to July 24, 2015. The Symposium was organized by Ortra Ltd. The ISSW30 focused on the state of knowledge of the following areas: Nozzle Flow, Supersonic and Hypersonic Flows with Shocks, Supersonic Jets, Chemical Kinetics, Chemical Reacting Flows, Detonation, Combustion, Ignition, Shock Wave Reflection and Interaction, Shock Wave Interaction with Obstacles, Shock Wave Interaction with Porous Media, Shock Wave Interaction with Granular Media, Shock Wave Interaction with Dusty Media, Plasma, Magnetohyrdrodynamics, Re-entry to Earth Atmosphere, Shock Waves in Rarefied Gases, Shock Waves in Condensed Matter (Solids and Liquids), Shock Waves in Dense Gases, Shock Wave Focusing, Richtmyer-Meshkov Instability, Shock Boundary Layer Interaction, Multiphase Flow, Blast Waves, Facilities, Flow Visualization, and Numerical Methods. The two volumes serve as a reference ...

  3. Biophoton emission induced by heat shock.

    Directory of Open Access Journals (Sweden)

    Katsuhiro Kobayashi

    Full Text Available Ultraweak biophoton emission originates from the generation of reactive oxygen species (ROS that are produced in mitochondria as by-products of cellular respiration. In healthy cells, the concentration of ROS is minimized by a system of biological antioxidants. However, heat shock changes the equilibrium between oxidative stress and antioxidant activity, that is, a rapid rise in temperature induces biophoton emission from ROS. Although the rate and intensity of biophoton emission was observed to increase in response to elevated temperatures, pretreatment at lower high temperatures inhibited photon emission at higher temperatures. Biophoton measurements are useful for observing and evaluating heat shock.

  4. Dynamical Properties of Internal Shocks Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Pe’er, Asaf; Long, Killian [Physics Department, University College Cork, Cork (Ireland); Casella, Piergiorgio [INAF, Osservatorio Astronomico di Roma, Via Frascati 33, I-00078 Monteporzio Catone (Italy)

    2017-09-01

    Internal shocks between propagating plasma shells, originally ejected at different times with different velocities, are believed to play a major role in dissipating the kinetic energy, thereby explaining the observed light curves and spectra in a large range of transient objects. Even if initially the colliding plasmas are cold, following the first collision, the plasma shells are substantially heated, implying that in a scenario of multiple collisions, most collisions take place between plasmas of non-zero temperatures. Here, we calculate the dynamical properties of plasmas resulting from a collision between arbitrarily hot plasma shells, moving at arbitrary speeds. We provide simple analytical expressions valid for both ultrarelativistic and Newtonian velocities for both hot and cold plasmas. We derive the minimum criteria required for the formation of the two-shock wave system, and show that in the relativistic limit, the minimum Lorentz factor is proportional to the square root of the ratio of the initial plasmas enthalpies. We provide basic scaling laws of synchrotron emission from both the forward and reverse-shock waves, and show how these can be used to deduce the properties of the colliding shells. Finally, we discuss the implications of these results in the study of several astronomical transients, such as X-ray binaries, radio-loud quasars, and gamma-ray bursts.

  5. 29th International Symposium on Shock Waves

    CERN Document Server

    Ranjan, Devesh

    2015-01-01

    This proceedings present the results of the 29th International Symposium on Shock Waves (ISSW29) which was held in Madison, Wisconsin, U.S.A., from July 14 to July 19, 2013. It was organized by the Wisconsin Shock Tube Laboratory, which is part of the College of Engineering of the University of Wisconsin-Madison. The ISSW29 focused on the following areas: Blast Waves, Chemically Reactive Flows, Detonation and Combustion,  Facilities, Flow Visualization, Hypersonic Flow, Ignition, Impact and Compaction, Industrial Applications, Magnetohydrodynamics, Medical and Biological Applications, Nozzle Flow, Numerical Methods, Plasmas, Propulsion, Richtmyer-Meshkov Instability, Shock-Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shock Waves in Condensed Matter, Shock Waves in Multiphase Flow, as well as Shock Waves in Rarefield Flow. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 29 and individuals interes...

  6. Emissive spectra of shock-heated argon

    International Nuclear Information System (INIS)

    Tang Jingyou; Gu Yan; Peng Qixian; Bai Yulin; Li Ping

    2003-01-01

    To study the radiant properties of argon under weak shock compression, an aluminum target filled with gaseous argon at ambient states was impacted by a tungsten alloy projectile which was launched from a two-stage light gun to 2.00 km/s. The radiant signals of single shock-compressed argon were recorded by a six-channel pyrometer and oscilloscopes, which varied with time linearly for the five channels from 405 nm to 700 nm and exponentially for the channel 800 nm, and the corresponding velocity of shock wave was determined to be 4.10 ± 0.09 km/s. By the present experiment, it has been shown that the absorbability of the shock-heated argon is low for visual light and the optical depths of argon gas turn from thin to thick as wavelengths gradually increase. The time-resolved spectra in the rising-front of the radiant signal in the re-shocked argon were recorded by means of an OMA, and strong emissive spectrum bands near 450 nm light-wave length but no linear spectrum were found. The emissive spectrum properties of shock-compression argon were qualitatively explained by the state parameters and ionization degree

  7. International emissions trading

    DEFF Research Database (Denmark)

    Boom, Jan Tjeerd

    This thesis discusses the design and political acceptability of international emissions trading. It is shown that there are several designs options for emissions trading at the national level that have a different impact on output and thereby related factors such as employment and consumer prices....... The differences in impact of the design make that governments may prefer different designs of emissions trading in different situations. The thesis furthermore establishes that international emissions trading may lead to higher overall emissions, which may make it a less attractive instrument....

  8. 28th International Symposium on Shock Waves

    CERN Document Server

    2012-01-01

    The University of Manchester hosted the 28th International Symposium on Shock Waves between 17 and 22 July 2011. The International Symposium on Shock Waves first took place in 1957 in Boston and has since become an internationally acclaimed series of meetings for the wider Shock Wave Community. The ISSW28 focused on the following areas: Blast Waves, Chemically Reacting Flows, Dense Gases and Rarefied Flows, Detonation and Combustion, Diagnostics, Facilities, Flow Visualisation, Hypersonic Flow, Ignition, Impact and Compaction, Multiphase Flow, Nozzle Flow, Numerical Methods, Propulsion, Richtmyer-Meshkov, Shockwave Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shockwave Phenomena and Applications, as well as Medical and Biological Applications. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 28 and individuals interested in these fields.

  9. International Shock-Wave Database: Current Status

    Science.gov (United States)

    Levashov, Pavel

    2013-06-01

    Shock-wave and related dynamic material response data serve for calibrating, validating, and improving material models over very broad regions of the pressure-temperature-density phase space. Since the middle of the 20th century vast amount of shock-wave experimental information has been obtained. To systemize it a number of compendiums of shock-wave data has been issued by LLNL, LANL (USA), CEA (France), IPCP and VNIIEF (Russia). In mid-90th the drawbacks of the paper handbooks became obvious, so the first version of the online shock-wave database appeared in 1997 (http://www.ficp.ac.ru/rusbank). It includes approximately 20000 experimental points on shock compression, adiabatic expansion, measurements of sound velocity behind the shock front and free-surface-velocity for more than 650 substances. This is still a useful tool for the shock-wave community, but it has a number of serious disadvantages which can't be easily eliminated: (i) very simple data format for points and references; (ii) minimalistic user interface for data addition; (iii) absence of history of changes; (iv) bad feedback from users. The new International Shock-Wave database (ISWdb) is intended to solve these and some other problems. The ISWdb project objectives are: (i) to develop a database on thermodynamic and mechanical properties of materials under conditions of shock-wave and other dynamic loadings, selected related quantities of interest, and the meta-data that describes the provenance of the measurements and material models; and (ii) to make this database available internationally through the Internet, in an interactive form. The development and operation of the ISWdb is guided by an advisory committee. The database will be installed on two mirrored web-servers, one in Russia and the other in USA (currently only one server is available). The database provides access to original experimental data on shock compression, non-shock dynamic loadings, isentropic expansion, measurements of sound

  10. A model for radio emission from solar coronal shocks

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, G. Q.; Chen, L.; Wu, D. J., E-mail: djwu@pmo.ac.cn [Purple Mountain Observatory, CAS, Nanjing 210008 (China)

    2014-05-01

    Solar coronal shocks are very common phenomena in the solar atmosphere and are believed to be the drivers of solar type II radio bursts. However, the microphysical nature of these emissions is still an open question. This paper proposes that electron cyclotron maser (ECM) emission is responsible for the generation of radiation from the coronal shocks. In the present model, an energetic ion beam accelerated by the shock first excites the Alfvén wave (AW), then the excited AW leads to the formation of a density-depleted duct along the foreshock boundary of the shock. In this density-depleted duct, the energetic electron beam produced via the shock acceleration can effectively excite radio emission by ECM instability. Our results show that this model may potentially be applied to solar type II radio bursts.

  11. A model for radio emission from solar coronal shocks

    International Nuclear Information System (INIS)

    Zhao, G. Q.; Chen, L.; Wu, D. J.

    2014-01-01

    Solar coronal shocks are very common phenomena in the solar atmosphere and are believed to be the drivers of solar type II radio bursts. However, the microphysical nature of these emissions is still an open question. This paper proposes that electron cyclotron maser (ECM) emission is responsible for the generation of radiation from the coronal shocks. In the present model, an energetic ion beam accelerated by the shock first excites the Alfvén wave (AW), then the excited AW leads to the formation of a density-depleted duct along the foreshock boundary of the shock. In this density-depleted duct, the energetic electron beam produced via the shock acceleration can effectively excite radio emission by ECM instability. Our results show that this model may potentially be applied to solar type II radio bursts.

  12. Radio emission from coronal and interplanetary shocks

    International Nuclear Information System (INIS)

    Cane, H.V.

    1987-01-01

    Observational data on coronal and interplanetary (IP) type II burst events associated with shock-wave propagation are reviewed, with a focus on the past and potential future contributions of space-based observatories. The evidence presented by Cane (1983 and 1984) in support of the hypothesis that the coronal (metric) and IP (kilometric) bursts are due to different shocks is summarized, and the fast-drift kilometric events seen at the same time as metric type II bursts (and designated shock-accelerated or shock-associated events) are characterized. The need for further observations at 0.5-20 MHz is indicated. 20 references

  13. Internal energy relaxation in shock wave structure

    International Nuclear Information System (INIS)

    Josyula, Eswar; Suchyta, Casimir J.; Boyd, Iain D.; Vedula, Prakash

    2013-01-01

    The Wang Chang-Uhlenbeck (WCU) equation is numerically integrated to characterize the internal structure of Mach 3 and Mach 5 shock waves in a gas with excitation in the internal energy states for the treatment of inelastic collisions. Elastic collisions are modeled with the hard sphere collision model and the transition rates for the inelastic collisions modified appropriately using probabilities based on relative velocities of the colliding particles. The collision integral is evaluated by the conservative discrete ordinate method [F. Tcheremissine, “Solution of the Boltzmann kinetic equation for high-speed flows,” Comput. Math. Math. Phys. 46, 315–329 (2006); F. Cheremisin, “Solution of the Wang Chang-Uhlenbeck equation,” Dokl. Phys. 47, 487–490 (2002)] developed for the Boltzmann equation. For the treatment of the diatomic molecules, the internal energy modes in the Boltzmann equation are described quantum mechanically given by the WCU equation. As a first step in the treatment of the inelastic collisions by the WCU equation, a two- and three-quantum system is considered to study the effect of the varying of (1) the inelastic cross section and (2) the energy gap between the quantum energy states. An alternative method, the direct simulation Monte Carlo method, is used for the Mach 3 shock wave to ensure the consistency of implementation in the two methods and there is an excellent agreement between the two methods. The results from the WCU implementation showed consistent trends for the Mach 3 and Mach5 standing shock waves simulations. Inelastic contributions change the downstream equilibrium state and allow the flow to transition to the equilibrium state further upstream

  14. H2 emission from non-stationary magnetized bow shocks

    Science.gov (United States)

    Tram, L. N.; Lesaffre, P.; Cabrit, S.; Gusdorf, A.; Nhung, P. T.

    2018-01-01

    When a fast moving star or a protostellar jet hits an interstellar cloud, the surrounding gas gets heated and illuminated: a bow shock is born that delineates the wake of the impact. In such a process, the new molecules that are formed and excited in the gas phase become accessible to observations. In this paper, we revisit models of H2 emission in these bow shocks. We approximate the bow shock by a statistical distribution of planar shocks computed with a magnetized shock model. We improve on previous works by considering arbitrary bow shapes, a finite irradiation field and by including the age effect of non-stationary C-type shocks on the excitation diagram and line profiles of H2. We also examine the dependence of the line profiles on the shock velocity and on the viewing angle: we suggest that spectrally resolved observations may greatly help to probe the dynamics inside the bow shock. For reasonable bow shapes, our analysis shows that low-velocity shocks largely contribute to H2 excitation diagram. This can result in an observational bias towards low velocities when planar shocks are used to interpret H2 emission from an unresolved bow. We also report a large magnetization bias when the velocity of the planar model is set independently. Our 3D models reproduce excitation diagrams in BHR 71 and Orion bow shocks better than previous 1D models. Our 3D model is also able to reproduce the shape and width of the broad H2 1-0S(1) line profile in an Orion bow shock (Brand et al. 1989).

  15. COLLISIONLESS SHOCKS IN A PARTIALLY IONIZED MEDIUM. II. BALMER EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Morlino, G.; Bandiera, R.; Blasi, P.; Amato, E. [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy)

    2012-12-01

    Strong shocks propagating into a partially ionized medium are often associated with optical Balmer lines. This emission is due to impact excitation of neutral hydrogen by hot protons and electrons in the shocked gas. The structure of such Balmer-dominated shocks has been computed in a previous paper, where the distribution function of neutral particles was derived from the appropriate Boltzmann equation including coupling with ions and electrons through charge exchange and ionization. This calculation showed how the presence of neutrals can significantly modify the shock structure through the formation of a neutral-induced precursor ahead of the shock. Here we follow up on our previous work and investigate the properties of the resulting Balmer emission, with the aim of using the observed radiation as a diagnostic tool for shock parameters. Our main focus is on supernova remnant shocks, and we find that, for typical parameters, the H{alpha} emission typically has a three-component spectral profile, where (1) a narrow component originates from upstream cold hydrogen atoms, (2) a broad component comes from hydrogen atoms that have undergone charge exchange with shocked protons downstream of the shock, and (3) an intermediate component is due to hydrogen atoms that have undergone charge exchange with warm protons in the neutral-induced precursor. The relative importance of these three components depends on the shock velocity, on the original degree of ionization, and on the electron-ion temperature equilibration level. The intermediate component, which is the main signature of the presence of a neutral-induced precursor, becomes negligible for shock velocities {approx}< 1500 km s{sup -1}. The width of the intermediate line reflects the temperature in the precursor, while the width of the narrow one is left unaltered by the precursor. In addition, we show that the profiles of both the intermediate and broad components generally depart from a thermal distribution, as a

  16. Internal defibrillation: pain perception of low energy shocks.

    Science.gov (United States)

    Steinhaus, David M; Cardinal, Debbie S; Mongeon, Luc; Musley, Shailesh Kumar; Foley, Laura; Corrigan, Susie

    2002-07-01

    Recently, device-based low energy cardoversion shocks have been used as therapy for AF. However, discomfort from internal low energy electrical shocks is poorly understood. The aim of this study was to evaluate pain perception with low energy internal discharges. Eighteen patients with ICD devices for malignant ventricular arrhythmias were recruited to receive shocks of 0.4 and 2 J in the nonsedated state. Discharges were delivered in a blinded, random order and questionnaires were used to determine discomfort levels and tolerability. Patients perceived discharges at these energies as relatively uncomfortable, averaging a score of 7.3 on a discomfort scale of 0-10, and could not distinguish 0.4-J shocks from 2-J shocks. Second shocks were perceived as more uncomfortable than initial discharges, regardless of the order in which the shocks were delivered. Despite the perceived discomfort, 83% of patients stated that they would tolerate discharges of this magnitude once per month, and 44% would tolerate weekly discharges. Patients perceive low energy discharges as painful and cannot distinguish between shocks of 0.4 and 2 J. The results suggest that ICD systems developed to treat atrial tachyarrhythmias should minimize the number of shocks delivered to terminate an atrial tachyarrhythmia episode. The majority of the patients tolerated low energy shocks provided the discharges are infrequent (once per month).

  17. Low emission internal combustion engine

    Science.gov (United States)

    Karaba, Albert M.

    1979-01-01

    A low emission, internal combustion compression ignition engine having a cylinder, a piston movable in the cylinder and a pre-combustion chamber communicating with the cylinder near the top thereof and in which low emissions of NO.sub.x are achieved by constructing the pre-combustion chamber to have a volume of between 70% and 85% of the combined pre-chamber and main combustion chamber volume when the piston is at top dead center and by variably controlling the initiation of fuel injection into the pre-combustion chamber.

  18. General relativistic study of astrophysical jets with internal shocks

    Science.gov (United States)

    Vyas, Mukesh K.; Chattopadhyay, Indranil

    2017-08-01

    We explore the possibility of the formation of steady internal shocks in jets around black holes. We consider a fluid described by a relativistic equation of state, flowing about the axis of symmetry (θ = 0) in a Schwarzschild metric. We use two models for the jet geometry: (I) a conical geometry and (II) a geometry with non-conical cross-section. A jet with conical geometry has a smooth flow, while the jet with non-conical cross-section undergoes multiple sonic points and even standing shock. The jet shock becomes stronger, as the shock location is situated farther from the central black hole. Jets with very high energy and very low energy do not harbour shocks, but jets with intermediate energies do harbour shocks. One advantage of these shocks, as opposed to shocks mediated by external medium, is that these shocks have no effect on the jet terminal speed, but may act as possible sites for particle acceleration. Typically, a jet with specific energy 1.8c2 will achieve a terminal speed of v∞ = 0.813c for jet with any geometry, where, c is the speed of light in vacuum. But for a jet of non-conical cross-section for which the length scale of the inner torus of the accretion disc is 40rg, then, in addition, a steady shock will form at rsh ˜ 7.5rg and compression ratio of R ˜ 2.7. Moreover, electron-proton jet seems to harbour the strongest shock. We will discuss possible consequences of such a scenario.

  19. Precursor Wave Emission Enhanced by Weibel Instability in Relativistic Shocks

    Science.gov (United States)

    Iwamoto, Masanori; Amano, Takanobu; Hoshino, Masahiro; Matsumoto, Yosuke

    2018-05-01

    We investigated the precursor wave emission efficiency in magnetized purely perpendicular relativistic shocks in pair plasmas. We extended our previous study to include the dependence of upstream magnetic field orientations. We performed two-dimensional particle-in-cell simulations and focused on two magnetic field orientations: the magnetic field in the simulation plane (i.e., in-plane configuration) and that perpendicular to the simulation plane (i.e., out-of-plane configuration). Our simulations in the in-plane configuration demonstrated that not only extraordinary but also ordinary mode waves are excited. We quantified the emission efficiency as a function of the magnetization parameter σ e and found that the large-amplitude precursor waves are emitted for a wide range of σ e . We found that especially at low σ e , the magnetic field generated by Weibel instability amplifies the ordinary mode wave power. The amplitude is large enough to perturb the upstream plasma, and transverse density filaments are generated as in the case of the out-of-plane configuration investigated in the previous study. We confirmed that our previous conclusion holds regardless of upstream magnetic field orientations with respect to the two-dimensional simulation plane. We discuss the precursor wave emission in three dimensions and the feasibility of wakefield acceleration in relativistic shocks based on our results.

  20. Asymmetric impacts of international energy shocks on macroeconomic activities

    International Nuclear Information System (INIS)

    Yeh, Fang-Yu; Hu, Jin-Li; Lin, Cheng-Hsun

    2012-01-01

    While limited by its scarcity of natural resources, the impacts of energy price changes on Taiwan's economic activities have been an important issue for social public and government authorities. This study applies the multivariate threshold model to investigate the effects of various international energy price shocks on Taiwan's macroeconomic activity. By separating energy price changes into the so-called decrease and increase regimes, we can realize different impacts of energy price changes and their shocks on economic output. The results confirm that there is an asymmetric threshold effect for the energy-output nexus. The optimal threshold levels are exactly where the oil price change is at 2.48%, the natural gas price change is at 0.66%, and the coal price change is at 0.25%. The impulse response analysis suggests that oil price and natural gas shocks have a delayed negative impact on macroeconomic activities. - Highlights: ► This study applies multivariate threshold model to investigate the effects of various international energy price shocks on Taiwan's macroeconomic activity. ► The results confirm that there is an asymmetric threshold effect for energy-output nexus. ► The optimal threshold levels are exactly found where oil price change is at 2.48%, natural gas price change is at 0.66%, and coal price change is at 0.25%.

  1. Austrian emission under international comparison

    International Nuclear Information System (INIS)

    Anderl, M.; Gager, M.; Gugele, B.; Huttunen, K.; Kurzweil, A.; Poupa, S.; Ritter, M.; Wappel, D.; Wieser, M.

    2004-01-01

    A comparison between anthropogenic emissions of CO 2 , CH 4 , N 2 O, SO 2 , NO x , volatile organic compounds (NMVOC), NH 3 and CO from the European Union, European Union candidate countries and Austria is presented. Data covers the years 1999-2001 and the emissions values per habitant are provided as well as a comparison against the Kyoto goals. In the middle of the European mean values are the austrian emissions values, austrian SO 2 emissions are the smallest, however CH 4 , CO and NMVOC emissions are over the European mean values. 8 figs., 6 tabs. (nevyjel)

  2. Line emission processes in atomic and molecular shocks

    International Nuclear Information System (INIS)

    Shull, J.M.

    1988-01-01

    The review discusses the observations and theoretical models of interstellar shock waves in diffuse and molecular clouds. After summarizing the relevant gas dynamics, atomic, molecular and grain processes, and physics of radiative and magnetic precursors, the author describes observational diagnostics of shocks. This paper concludes with a discussion of two topics: unstable or non-steady shocks and thermal conduction in metal-rich shocks

  3. X-ray emission from reverse-shocked ejecta in supernova remnants

    Science.gov (United States)

    Cioffi, Denis F.; Mckee, Christopher F.

    1990-01-01

    A simple physical model of the dynamics of a young supernova remnant is used to derive a straightforward kinematical description of the reverse shock. With suitable approximations, formulae can then be developed to give the X-ray emission of the reverse-shocked ejecta. The results are found to agree favorably with observations of SN1006.

  4. Multi-messenger Light Curves from Gamma-Ray Bursts in the Internal Shock Model

    Energy Technology Data Exchange (ETDEWEB)

    Bustamante, Mauricio [Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University, Columbus, OH 43210 (United States); Heinze, Jonas; Winter, Walter [Deutsches Elektronen-Synchrotron (DESY), Platanenallee 6, D-15738 Zeuthen (Germany); Murase, Kohta, E-mail: bustamanteramirez.1@osu.edu, E-mail: walter.winter@desy.de, E-mail: jonas.heinze@desy.de, E-mail: murase@psu.edu [Center for Particle and Gravitational Astrophysics, The Pennsylvania State University, University Park, PA16802 (United States)

    2017-03-01

    Gamma-ray bursts (GRBs) are promising as sources of neutrinos and cosmic rays. In the internal shock scenario, blobs of plasma emitted from a central engine collide within a relativistic jet and form shocks, leading to particle acceleration and emission. Motivated by present experimental constraints and sensitivities, we improve the predictions of particle emission by investigating time-dependent effects from multiple shocks. We produce synthetic light curves with different variability timescales that stem from properties of the central engine. For individual GRBs, qualitative conclusions about model parameters, neutrino production efficiency, and delays in high-energy gamma-rays can be deduced from inspection of the gamma-ray light curves. GRBs with fast time variability without additional prominent pulse structure tend to be efficient neutrino emitters, whereas GRBs with fast variability modulated by a broad pulse structure can be inefficient neutrino emitters and produce delayed high-energy gamma-ray signals. Our results can be applied to quantitative tests of the GRB origin of ultra-high-energy cosmic rays, and have the potential to impact current and future multi-messenger searches.

  5. Multi-messenger light curves from gamma-ray bursts in the internal shock model

    Energy Technology Data Exchange (ETDEWEB)

    Bustamante, Mauricio [Ohio State Univ., Columbus, OH (United States). Center for Cosmology and AstroParticle Physics (CCAPP); Ohio State Univ., Columbus, OH (United States). Dept. of Physics; Murase, Kohta [Pennsylvania State Univ., University Park, PA (United States). Center for Particle and Gravitational Astrophysics; Pennsylvania State Univ., University Park, PA (United States). Dept. of Astronomy and Astrophysics; Winter, Walter [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2016-06-15

    Gamma-ray bursts (GRBs) are promising as sources of neutrinos and cosmic rays. In the internal shock scenario, blobs of plasma emitted from a central engine collide within a relativistic jet and form shocks, leading to particle acceleration and emission. Motivated by present experimental constraints and sensitivities, we improve the predictions of particle emission by investigating time-dependent effects from multiple shocks. We produce synthetic light curves with different variability timescales that stem from properties of the central engine. For individual GRBs, qualitative conclusions about model parameters, neutrino production efficiency, and delays in high-energy gamma rays can be deduced from inspection of the gamma-ray light curves. GRBs with fast time variability without additional prominent pulse structure tend to be efficient neutrino emitters, whereas GRBs with fast variability modulated by a broad pulse structure tend to be inefficient neutrino emitters and produce delayed high-energy gamma-ray signals. Our results can be applied to quantitative tests of the GRB origin of ultra-high-energy cosmic rays, and have the potential to impact current and future multi-messenger searches.

  6. Galaxy-Wide Shocks in the H$\\alpha$ Emission of Nearby Galaxy Mergers

    Science.gov (United States)

    Mortazavi, S. Alireza; Lotz, Jennifer M.

    2018-01-01

    We examine the properties of shocked gas produced as a result of binary galaxy interactions, using H$\\alpha$ emission in a sample 22 mergers observed with SparsePak Integral Field Unit (IFU) at Kitt Peak National Observatory (KPNO). Our sample consists of major and minor tidally interacting galaxies (mass ratio $1text{f}_\\text{shocked}$, and examine the spatial distribution of shocks. We find that close galaxy pairs have, on average, a higher shock fraction than wide pairs, and our coalesced mergers have the highest average $\\text{f}_\\text{shocked}$. Additionally, we find for the first time, correlations between mass ratio, mass of the companion, and $\\text{f}_\\text{shocked}$ in tidally interacting galaxy pairs. Among the non-coalesced systems in our sample, the galaxy pairs with more equal light ratio (stellar mass ratio) tend to have a higher average $\\text{f}_\\text{shocked}$. Also, the primary (more massive) companions are on average slightly more shocked than the secondary (less massive) ones. Utilizing dynamical models in the literature and this work, we inspect trends between $\\text{f}_\\text{shocked}$ and the reconstructed encounter parameters. In this very limited sample, we find that the orbital pericentric separation is correlated with shock fraction, consistent with shocks being produced by the chain of events caused by the tidal impulse during the first passage. These results lay a basis for furture analysis using the higher statistics provided by the on-going and future IFU galaxy surveys.

  7. International Emissions Trading : Design and Political Acceptability

    NARCIS (Netherlands)

    Boom, Jan Tjeerd

    2006-01-01

    This thesis discusses the design and political acceptability of international emissions trading. It is shown that there are several designs options for emissions trading at the national level that have a different impact on output and thereby related factors such as employment and consumer prices.

  8. Laser-excited optical emission response of CdTe quantum dot/polymer nanocomposite under shock compression

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Pan [LNM, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0405 (United States); Kang, Zhitao; Summers, Christopher J. [Phosphor Technology Center of Excellence, Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, Georgia 30332-0826 (United States); Bansihev, Alexandr A.; Christensen, James M.; Dlott, Dana D. [School of Chemical Sciences and Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Breidenich, Jennifer; Scripka, David A.; Thadhani, Naresh N. [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States); Zhou, Min, E-mail: min.zhou@gatech.edu [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0405 (United States); School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States)

    2016-01-04

    Laser-driven shock compression experiments and corresponding finite element method simulations are carried out to investigate the blueshift in the optical emission spectra under continuous laser excitation of a dilute composite consisting of 0.15% CdTe quantum dots by weight embedded in polyvinyl alcohol polymer. This material is a potential candidate for use as internal stress sensors. The analyses focus on the time histories of the wavelength blue-shift for shock loading with pressures up to 7.3 GPa. The combined measurements and calculations allow a relation between the wavelength blueshift and pressure for the loading conditions to be extracted. It is found that the blueshift first increases with pressure to a maximum and subsequently decreases with pressure. This trend is different from the monotonic increase of blueshift with pressure observed under conditions of quasistatic hydrostatic compression. Additionally, the blueshift in the shock experiments is much smaller than that in hydrostatic experiments at the same pressure levels. The differences in responses are attributed to the different stress states achieved in the shock and hydrostatic experiments and the time dependence of the mechanical response of the polymer in the composite. The findings offer a potential guide for the design and development of materials for internal stress sensors for shock conditions.

  9. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016

    NARCIS (Netherlands)

    Rhodes, Andrew; Evans, Laura E.; Alhazzani, Waleed; Levy, Mitchell M.; Antonelli, Massimo; Ferrer, Ricard; Kumar, Anand; Sevransky, Jonathan E.; Sprung, Charles L.; Nunnally, Mark E.; Rochwerg, Bram; Rubenfeld, Gordon D.; Angus, Derek C.; Annane, Djillali; Beale, Richard J.; Bellinghan, Geoffrey J.; Bernard, Gordon R.; Chiche, Jean-Daniel; Coopersmith, Craig; de Backer, Daniel P.; French, Craig J.; Fujishima, Seitaro; Gerlach, Herwig; Hidalgo, Jorge Luis; Hollenberg, Steven M.; Jones, Alan E.; Karnad, Dilip R.; Kleinpell, Ruth M.; Koh, Younsuck; Lisboa, Thiago Costa; Machado, Flavia R.; Marini, John J.; Marshall, John C.; Mazuski, John E.; McIntyre, Lauralyn A.; McLean, Anthony S.; Mehta, Sangeeta; Moreno, Rui P.; Myburgh, John; Navalesi, Paolo; Nishida, Osamu; Osborn, Tiffany M.; Perner, Anders; Plunkett, Colleen M.; Ranieri, Marco; Schorr, Christa A.; Seckel, Maureen A.; Seymour, Christopher W.; Shieh, Lisa; Shukri, Khalid A.; Simpson, Steven Q.; Singer, Mervyn; Thompson, B. Taylor; Townsend, Sean R.; van der Poll, Thomas; Vincent, Jean-Louis; Wiersinga, W. Joost; Zimmerman, Janice L.; Dellinger, R. Phillip

    2017-01-01

    Objective: To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012!' Design: A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings

  10. International oil shocks and household consumption in China

    International Nuclear Information System (INIS)

    Zhang, Dayong; Broadstock, David C.; Cao, Hong

    2014-01-01

    We investigate the impacts that oil price shocks have on residential consumption in China. While it is well understood that oil prices affect consumption in a multitude of ways, the timing and directness of these effects on specific consumption categories is not clear. We demonstrate that the most immediate and direct effect passes through transportation consumption, as might be expected. But we also show that significant effects pass through consumption in other sectors—including “food and clothes”, “medical expenditure”, and other general “living expenditure”—with less immediacy. Given the results, particularly observed asymmetries with respect to rises and falls in international oil prices, we discuss some implications for future adjustments to domestic price policies, in particular the case for removal of domestic price regulation. - Highlights: • We study the impact of oil price shocks on residential consumption in China. • The most immediate effect passes through expenditure on transportation. • Effects also appear for health, education and food and clothing expenditure. • Existing price regulation offers no great benefit. • We argue that a compelling case for removing current price regulation exists

  11. Transmission of Shock across International Stock Markets: An Econometric Analysis

    Directory of Open Access Journals (Sweden)

    Shalini TALWAR

    2018-05-01

    Full Text Available The risk of spillover of volatility among international stock markets has increased manifold and it needs to be diagnosed comprehensively. In this paper, the authors have used 11 stock indices to identify influential markets and detect the direction of transmission of shock across markets in different time zones using Granger causality test, Johansen cointegration test and vector autoregression. The findings of VAR show that the forecast error at the 10-day horizon explained by their own innovation is highest for the Australian and Chinese markets followed by Japan, India, Brazil and Russia.Markets of Germany, UK, USA and Canada are influenced by the Australian market. In fact, the Australian market is seen to be the most influential market among the markets under the study. The impact of Chinese and Canadian markets is found to be the least. These results can be useful for optimal option valuation, effective portfolio allocation and performance benchmarking

  12. On-line monitoring on thermal shock damage of ceramics using acoustic emission

    International Nuclear Information System (INIS)

    Lee, Jin Kyung; Lee, Joon Hyun; Song, Sang Hun

    1999-01-01

    The objective of this paper is to investigate the degree of the thermal shock damage on alumina ceramic using acoustic emission technique. For this purpose, alumina ceramic specimen was heated in the elastic furnace and then was quenched into the water tank. When the specimen was quenched into water tank, a lot of micro-cracks were generated on the surface of specimen due to the thermal shock damage. In this study, acoustic emission technique was used to evaluate the elastic waves generated by the crack initiation and propagation on the surface of specimen. It was found that when the micro-crack was initiated on the surface of specimen, AE signals were the higher in amplitude than those of bubbling effect and crack propagation. A lot of AE events were generated at the first thermal shock, the number of AE events decreased gradually as the thermal shock cycle increased.

  13. Phenomenology of reverse-shock emission in the optical afterglows of gamma-ray bursts

    International Nuclear Information System (INIS)

    Japelj, J.; Kopač, D.; Gomboc, A.; Kobayashi, S.; Harrison, R.; Virgili, F. J.; Mundell, C. G.; Guidorzi, C.; Melandri, A.

    2014-01-01

    We use a parent sample of 118 gamma-ray burst (GRB) afterglows, with known redshift and host galaxy extinction, to separate afterglows with and without signatures of dominant reverse-shock (RS) emission and to determine which physical conditions lead to a prominent reverse-shock emission. We identify 10 GRBs with reverse-shock signatures: 990123, 021004, 021211, 060908, 061126, 080319B, 081007, 090102, 090424, and 130427A. By modeling their optical afterglows with reverse- and forward-shock analytic light curves and using Monte Carlo simulations, we estimate the parameter space of the physical quantities describing the ejecta and circumburst medium. We find that physical properties cover a wide parameter space and do not seem to cluster around any preferential values. Comparing the rest-frame optical, X-ray, and high-energy properties of the larger sample of non-RS-dominated GRBs, we show that the early-time (<1 ks) optical spectral luminosity, X-ray afterglow luminosity, and γ-ray energy output of our reverse-shock dominated sample do not differ significantly from the general population at early times. However, the GRBs with dominant reverse-shock emission have fainter than average optical forward-shock emission at late times (>10 ks). We find that GRBs with an identifiable reverse-shock component show a high magnetization parameter R B = ε B,r /ε B,f ∼ 2-10 4 . Our results are in agreement with the mildly magnetized baryonic jet model of GRBs.

  14. Bright emissive core-shell spherical microparticles for shock compression spectroscopy

    International Nuclear Information System (INIS)

    Christensen, James M.; Banishev, Alexandr A.; Dlott, Dana D.

    2014-01-01

    Experiments were performed to study the response to shock compression of rhodamine 6G (R6G) dye encapsulated in 1.25 μm diameter silica microspheres. When R6G was encapsulated in microspheres, the emission intensity under steady-state irradiation (the brightness) was 3.4 times greater than the same dye in solution (the free dye). At least part of the brightness improvement was caused by an enhanced radiative rate. When the microspheres were embedded in poly-methylmethacrylate subjected to planar shocks in the 3–8.4 GPa range by laser-driven flyer plates, the dye emission redshifted and lost intensity. The dye emission redshift represents an instantaneous response to changes in the local density. In free dye samples, the shock-induced intensity loss had considerably slower rise times and fall times than the redshift. When dye was encapsulated in microspheres, the time dependence of the intensity loss matched the redshift almost exactly over a range of shock pressures and durations. The faster response to shock of dye in silica microspheres was explained by dye photophysics. The microsphere environment decreased the singlet state lifetime, which decreased the rise time, and it also decreased the triplet state lifetime, which decreased the fall time. Since it is much easier and more convenient to make measurements of intensity rather than spectral shift, these microspheres represent a substantial improvement in optical sensors to monitor shock compression of microstructured materials.

  15. Particle Acceleration, Magnetic Field Generation, and Emission in Relativistic Shocks

    Science.gov (United States)

    Nishikawa, Ken-IchiI.; Hededal, C.; Hardee, P.; Richardson, G.; Preece, R.; Sol, H.; Fishman, G.

    2004-01-01

    Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, two-streaming instability, and the Weibel instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle (m) code, we have investigated particle acceleration associated with a relativistic jet front propagating through an ambient plasma with and without initial magnetic fields. We find only small differences in the results between no ambient and weak ambient parallel magnetic fields. Simulations show that the Weibel instability created in the collisionless shock front accelerates particles perpendicular and parallel to the jet propagation direction. New simulations with an ambient perpendicular magnetic field show the strong interaction between the relativistic jet and the magnetic fields. The magnetic fields are piled up by the jet and the jet electrons are bent, which creates currents and displacement currents. At the nonlinear stage, the magnetic fields are reversed by the current and the reconnection may take place. Due to these dynamics the jet and ambient electron are strongly accelerated in both parallel and perpendicular directions.

  16. Streak-photographic investigation of shock wave emission after laser-induced plasma formation in water

    Science.gov (United States)

    Noack, Joachim; Vogel, Alfred

    1995-05-01

    The shock wave emission after dielectric breakdown in water was investigated to assess potential shock wave effects in plasma mediated tissue ablation and intraocular photodisruption. Of particular interest was the dependence of shock wave pressure as a function of distance from the plasma for different laser pulse energies. We have generated plasmas in water with a Nd:YAG laser system delivering pulses of 6 ns duration. The pulses, with energies between 0.4 and 36 mJ (approximately equals 180 times threshold), were focused into a cuvette containing distilled water. The shock wave was visualized with streak photography combined with a schlieren technique. An important advantage of this technique is that the shock position as a function of time can directly be obtained from a single streak and hence a single event. Other methods (e.g. flash photography or passage time measurements between fixed locations) in contrast rely on reproducible events. Using the shock wave speed obtained from the streak images, shock wave peak pressures were calculated providing detailed information on the propagation of the shock. The shock peak pressure as a function of distance r from the optical axis was found to decrease faster than 1/r2 in regions up to distances of 100-150 micrometers . For larger distances it was found to be roughly proportional to 1/r. The scaling law for maximum shock pressure p, at a given distance was found to be proportional to the square root of the laser pulse energy E for distances of 50-200 micrometers from the optical axis.

  17. BROAD N2H+ EMISSION TOWARD THE PROTOSTELLAR SHOCK L1157-B1

    International Nuclear Information System (INIS)

    Codella, C.; Fontani, F.; Gómez-Ruiz, A.; Vasta, M.; Viti, S.; Ceccarelli, C.; Lefloch, B.; Podio, L.; Benedettini, M.; Busquet, G.; Caselli, P.

    2013-01-01

    We present the first detection of N 2 H + toward a low-mass protostellar outflow, namely, the L1157-B1 shock, at ∼0.1 pc from the protostellar cocoon. The detection was obtained with the IRAM 30 m antenna. We observed emission at 93 GHz due to the J = 1-0 hyperfine lines. Analysis of this emission coupled with HIFI CHESS multiline CO observations leads to the conclusion that the observed N 2 H + (1-0) line originated from the dense (≥10 5 cm –3 ) gas associated with the large (20''-25'') cavities opened by the protostellar wind. We find an N 2 H + column density of a few 10 12 cm –2 corresponding to an abundance of (2-8) × 10 –9 . The N 2 H + abundance can be matched by a model of quiescent gas evolved for more than 10 4 yr, i.e., for more than the shock kinematical age (≅2000 yr). Modeling of C-shocks confirms that the abundance of N 2 H + is not increased by the passage of the shock. In summary, N 2 H + is a fossil record of the pre-shock gas, formed when the density of the gas was around 10 4 cm –3 , and then further compressed and accelerated by the shock

  18. Hard X-ray emission from accretion shocks around galaxy clusters

    Science.gov (United States)

    Kushnir, Doron; Waxman, Eli

    2010-02-01

    We show that the hard X-ray (HXR) emission observed from several galaxy clusters is consistent with a simple model, in which the nonthermal emission is produced by inverse Compton scattering of cosmic microwave background photons by electrons accelerated in cluster accretion shocks: The dependence of HXR surface brightness on cluster temperature is consistent with that predicted by the model, and the observed HXR luminosity is consistent with the fraction of shock thermal energy deposited in relativistic electrons being lesssim0.1. Alternative models, where the HXR emission is predicted to be correlated with the cluster thermal emission, are disfavored by the data. The implications of our predictions to future HXR observations (e.g. by NuStar, Simbol-X) and to (space/ground based) γ-ray observations (e.g. by Fermi, HESS, MAGIC, VERITAS) are discussed.

  19. Hard X-ray emission from accretion shocks around galaxy clusters

    Energy Technology Data Exchange (ETDEWEB)

    Kushnir, Doron; Waxman, Eli, E-mail: doron.kushnir@weizmann.ac.il, E-mail: eli.waxman@weizmann.ac.il [Physics Faculty, Weizmann Institute of Science, PO Box 26, Rehovot (Israel)

    2010-02-01

    We show that the hard X-ray (HXR) emission observed from several galaxy clusters is consistent with a simple model, in which the nonthermal emission is produced by inverse Compton scattering of cosmic microwave background photons by electrons accelerated in cluster accretion shocks: The dependence of HXR surface brightness on cluster temperature is consistent with that predicted by the model, and the observed HXR luminosity is consistent with the fraction of shock thermal energy deposited in relativistic electrons being ∼<0.1. Alternative models, where the HXR emission is predicted to be correlated with the cluster thermal emission, are disfavored by the data. The implications of our predictions to future HXR observations (e.g. by NuStar, Simbol-X) and to (space/ground based) γ-ray observations (e.g. by Fermi, HESS, MAGIC, VERITAS) are discussed.

  20. Hard X-ray emission from accretion shocks around galaxy clusters

    International Nuclear Information System (INIS)

    Kushnir, Doron; Waxman, Eli

    2010-01-01

    We show that the hard X-ray (HXR) emission observed from several galaxy clusters is consistent with a simple model, in which the nonthermal emission is produced by inverse Compton scattering of cosmic microwave background photons by electrons accelerated in cluster accretion shocks: The dependence of HXR surface brightness on cluster temperature is consistent with that predicted by the model, and the observed HXR luminosity is consistent with the fraction of shock thermal energy deposited in relativistic electrons being ∼<0.1. Alternative models, where the HXR emission is predicted to be correlated with the cluster thermal emission, are disfavored by the data. The implications of our predictions to future HXR observations (e.g. by NuStar, Simbol-X) and to (space/ground based) γ-ray observations (e.g. by Fermi, HESS, MAGIC, VERITAS) are discussed

  1. Broadband Electromagnetic Emission from PZT Ferroelectric Ceramics after Shock Loading

    Directory of Open Access Journals (Sweden)

    Fiodoras ANISIMOVAS

    2013-12-01

    Full Text Available It was experimentally registered pulsed electromagnetic (EM radiation in frequency range higher than television one using wideband horns with coaxial and waveguide outputs. The EM radiation was received during shock loading of lead zirconate titanate (PZT ceramics cylinders in conventional piezoelectric ignition mechanisms. Digital oscilloscope allows registering whole series of EM pulses and each pulse from the series transmitted from horn antenna of (1 – 18 GHz operating band frequencies. There is (1 – 4 ms delay between the shock and the first pulse of the series. Duration of the series is about (3 – 4 ms. The PZT cylinders were cleaved along their axes and the surfaces formed in the process were investigated by scanning electron microscope. It was concluded that from electrical point of view PZT ceramics contain interacting subsystems. It was found that EM radiation spectrum of pulse detected by waveguide detector heads has harmonics reaching 80 GHz. Presence of harmonics higher than 20 GHz indicates on radiation due to deceleration of electrons emitted during the switching. The EM pulses in the series appear randomly and have different amplitudes which partly confirmed thesis on independent switching dynamics of small volumes governed by a local electric field.DOI: http://dx.doi.org/10.5755/j01.ms.19.4.3137

  2. SUB-PHOTOSPHERIC EMISSION FROM RELATIVISTIC RADIATION MEDIATED SHOCKS IN GRBs

    International Nuclear Information System (INIS)

    Bromberg, Omer; Mikolitzky, Ziv; Levinson, Amir

    2011-01-01

    It is proposed that the prompt emission observed in bursts that exhibit a thermal component originates from relativistic radiation mediated shocks (RRMS) that form below the photosphere of the gamma-ray burst (GRB) outflow. It is argued that such shocks are expected to form in luminous bursts via collisions of shells that propagate with moderate Lorentz factors Γ ∼< 500. Faster shells will collide above the photosphere to form collisionless shocks. We demonstrate that in events like GRB 090902B a substantial fraction of the explosion energy is dissipated below the photosphere, in a region of moderate optical depth τ ∼< 300, whereas in GRB 080916C the major fraction of the energy dissipates above the photosphere. We show that under conditions anticipated in many GRBs, such RRMS convect enough radiation upstream to render photon production in the shock transition negligible, unlike the case of shock breakout in supernovae. The resulting spectrum, as measured in the shock frame, has a relatively low thermal peak, followed by a broad, nonthermal component extending up to the Klein-Nishina limit.

  3. The 'spontaneous' acoustic emission of the shock front in a perfect fluid: solving a riddle

    International Nuclear Information System (INIS)

    Brun, Louis

    2013-06-01

    In the fifties, S. D'yakov discovered that theory allows for suitable EOS shock fronts to emit acoustic waves 'spontaneously'. Section 90 of Fluid Mechanics of Landau and Lifshitz, 2. Ed., deals with the phenomenon, leaving it unexplained. This open question was chosen to introduce a monograph in progress about 'the shock front in the perfect fluid'. The novelty of our approach consists in having the phenomenon generated - which means it is non-spontaneous -- from an appropriate solicitation of the front and studying its development analytically. The non classical source and mechanism of the emission are thus brought to light. (author)

  4. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016

    NARCIS (Netherlands)

    Rhodes, Andrew; Evans, Laura E.; Alhazzani, Waleed; Levy, Mitchell M.; Antonelli, Massimo; Ferrer, Ricard; Kumar, Anand; Sevransky, Jonathan E.; Sprung, Charles L.; Nunnally, Mark E.; Rochwerg, Bram; Rubenfeld, Gordon D.; Angus, Derek C.; Annane, Djillali; Beale, Richard J.; Bellinghan, Geoffrey J.; Bernard, Gordon R.; Chiche, Jean-Daniel; Coopersmith, Craig; de Backer, Daniel P.; French, Craig J.; Fujishima, Seitaro; Gerlach, Herwig; Hidalgo, Jorge Luis; Hollenberg, Steven M.; Jones, Alan E.; Karnad, Dilip R.; Kleinpell, Ruth M.; Koh, Younsuk; Lisboa, Thiago Costa; Machado, Flavia R.; Marini, John J.; Marshall, John C.; Mazuski, John E.; McIntyre, Lauralyn A.; McLean, Anthony S.; Mehta, Sangeeta; Moreno, Rui P.; Myburgh, John; Navalesi, Paolo; Nishida, Osamu; Osborn, Tiffany M.; Perner, Anders; Plunkett, Colleen M.; Ranieri, Marco; Schorr, Christa A.; Seckel, Maureen A.; Seymour, Christopher W.; Shieh, Lisa; Shukri, Khalid A.; Simpson, Steven Q.; Singer, Mervyn; Thompson, B. Taylor; Townsend, Sean R.; van der Poll, Thomas; Vincent, Jean-Louis; Wiersinga, W. Joost; Zimmerman, Janice L.; Dellinger, R. Phillip

    2017-01-01

    To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012". A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee

  5. X-RAY EMISSION FROM SN 2004dj: A TALE OF TWO SHOCKS

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborti, Sayan; Yadav, Naveen; Ray, Alak [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Colaba, Mumbai 400 005 (India); Smith, Randall [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chandra, Poonam [Department of Physics, Royal Military College of Canada, Kingston, ON K7K 7B4 (Canada); Pooley, David, E-mail: schakraborti@fas.harvard.edu [Department of Physics, Sam Houston State University, Huntsville, TX (United States)

    2012-12-20

    Type IIP (Plateau) supernovae are the most commonly observed variety of core-collapse events. They have been detected in a wide range of wavelengths from radio, through optical to X-rays. The standard picture of a Type IIP supernova has the blastwave interacting with the progenitor's circumstellar matter to produce a hot region bounded by a forward and a reverse shock. This region is thought to be responsible for most of the X-ray and radio emission from these objects. Yet the origin of X-rays from these supernovae is not well understood quantitatively. The relative contributions of particle acceleration and magnetic field amplification in generating the X-ray and radio emission need to be determined. In this work, we analyze archival Chandra observations of SN 2004dj, one of the nearest supernovae since SN 1987A, along with published radio and optical information. We determine the pre-explosion mass-loss rate, blastwave velocity, electron acceleration, and magnetic field amplification efficiencies. We find that a greater fraction of the thermal energy goes into accelerating electrons than into amplifying magnetic fields. We conclude that the X-ray emission arises out of a combination of inverse Compton scattering by non-thermal electrons accelerated in the forward shock and thermal emission from supernova ejecta heated by the reverse shock.

  6. High-energy Emission from Nonrelativistic Radiative Shocks: Application to Gamma-Ray Novae

    Science.gov (United States)

    Vurm, Indrek; Metzger, Brian D.

    2018-01-01

    The observation of GeV gamma-rays from novae by Fermi/LAT demonstrates that the nonrelativistic radiative shocks in these systems can accelerate particles to energies of at least ∼10 GeV. The low-energy extension of the same nonthermal particle distribution inevitably gives rise to emission in the hard X-ray band. Above ≳ 10 {keV}, this radiation can escape the system without significant absorption/attenuation, and can potentially be detected by NuSTAR. We present theoretical models for hard X-ray and gamma-ray emission from radiative shocks in both leptonic and hadronic scenarios, accounting for the rapid evolution of the downstream properties due to the fast cooling of thermal plasma. We find that due to strong Coulomb losses, only a fraction of {10}-4{--}{10}-3 of the gamma-ray luminosity is radiated in the NuSTAR band; nevertheless, this emission could be detectable simultaneously with the LAT emission in bright gamma-ray novae with a ∼50 ks exposure. The spectral slope in hard X-rays is α ≈ 0 for typical nova parameters, thus serving as a testable prediction of the model. Our work demonstrates how combined hard X-ray and gamma-ray observations can be used to constrain properties of the nova outflow (velocity, density, and mass outflow rate) and particle acceleration at the shock. A very low X-ray to gamma-ray luminosity ratio ({L}{{X}}/{L}γ ≲ 5× {10}-4) would disfavor leptonic models for the gamma-ray emission. Our model can also be applied to other astrophysical environments with radiative shocks, including SNe IIn and colliding winds in massive star binaries.

  7. THERMAL X-RAY EMISSION FROM THE SHOCKED STELLAR WIND OF PULSAR GAMMA-RAY BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Zabalza, V.; Paredes, J. M. [Departament d' Astronomia i Meteorologia, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona (IEEC-UB), Marti i Franques 1, E08028 Barcelona (Spain); Bosch-Ramon, V., E-mail: vzabalza@am.ub.es [Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2 (Ireland)

    2011-12-10

    Gamma-ray-loud X-ray binaries are binary systems that show non-thermal broadband emission from radio to gamma rays. If the system comprises a massive star and a young non-accreting pulsar, their winds will collide producing broadband non-thermal emission, most likely originated in the shocked pulsar wind. Thermal X-ray emission is expected from the shocked stellar wind, but until now it has neither been detected nor studied in the context of gamma-ray binaries. We present a semi-analytic model of the thermal X-ray emission from the shocked stellar wind in pulsar gamma-ray binaries, and find that the thermal X-ray emission increases monotonically with the pulsar spin-down luminosity, reaching luminosities of the order of 10{sup 33} erg s{sup -1}. The lack of thermal features in the X-ray spectrum of gamma-ray binaries can then be used to constrain the properties of the pulsar and stellar winds. By fitting the observed X-ray spectra of gamma-ray binaries with a source model composed of an absorbed non-thermal power law and the computed thermal X-ray emission, we are able to derive upper limits on the spin-down luminosity of the putative pulsar. We applied this method to LS 5039, the only gamma-ray binary with a radial, powerful wind, and obtain an upper limit on the pulsar spin-down luminosity of {approx}6 Multiplication-Sign 10{sup 36} erg s{sup -1}. Given the energetic constraints from its high-energy gamma-ray emission, a non-thermal to spin-down luminosity ratio very close to unity may be required.

  8. SHOCKED POSTSTARBUST GALAXY SURVEY. I. CANDIDATE POST-STARBUST GALAXIES WITH EMISSION LINE RATIOS CONSISTENT WITH SHOCKS

    Energy Technology Data Exchange (ETDEWEB)

    Alatalo, Katherine; Rich, Jeffrey A. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Cales, Sabrina L. [Yale Center for Astronomy and Astrophysics, Physics Department, Yale University, New Haven, CT 06511 (United States); Appleton, Philip N.; Lanz, Lauranne [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Kewley, Lisa J.; Medling, Anne M. [Research School of Astronomy and Astrophysics, Australian National University, Cotter Road, Weston ACT 2611 (Australia); Lacy, Mark; Nyland, Kristina, E-mail: kalatalo@carnegiescience.edu [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States)

    2016-06-01

    There are many mechanisms by which galaxies can transform from blue, star-forming spirals, to red, quiescent early-type galaxies, but our current census of them does not form a complete picture. Recent observations of nearby case studies have identified a population of galaxies that quench “quietly.” Traditional poststarburst searches seem to catch galaxies only after they have quenched and transformed, and thus miss any objects with additional ionization mechanisms exciting the remaining gas. The Shocked POststarburst Galaxy Survey (SPOGS) aims to identify transforming galaxies, in which the nebular lines are excited via shocks instead of through star formation processes. Utilizing the Oh-Sarzi-Schawinski-Yi (OSSY) measurements on the Sloan Digital Sky Survey Data Release 7 catalog, we applied Balmer absorption and shock boundary criteria to identify 1067 SPOG candidates (SPOGs*) within z = 0.2. SPOGs* represent 0.2% of the OSSY sample galaxies that exceed the continuum signal-to-noise cut (and 0.7% of the emission line galaxy sample). SPOGs* colors suggest that they are in an earlier phase of transition than OSSY galaxies that meet an “E+A” selection. SPOGs* have a 13% 1.4 GHz detection rate from the Faint Images of the Radio Sky at Twenty Centimeters Survey, higher than most other subsamples, and comparable only to low-ionization nuclear emission line region hosts, suggestive of the presence of active galactic nuclei (AGNs). SPOGs* also have stronger Na i D absorption than predicted from the stellar population, suggestive of cool gas being driven out in galactic winds. It appears that SPOGs* represent an earlier phase in galaxy transformation than traditionally selected poststarburst galaxies, and that a large proportion of SPOGs* also have properties consistent with disruption of their interstellar media, a key component to galaxy transformation. It is likely that many of the known pathways to transformation undergo a SPOG phase. Studying this sample of

  9. X-RAY EMISSION FROM SUPERNOVAE IN DENSE CIRCUMSTELLAR MATTER ENVIRONMENTS: A SEARCH FOR COLLISIONLESS SHOCKS

    International Nuclear Information System (INIS)

    Ofek, E. O.; Gal-Yam, A.; Yaron, O.; Arcavi, I.; Fox, D.; Cenko, S. B.; Filippenko, A. V.; Bloom, J. S.; Sullivan, M.; Gnat, O.; Frail, D. A.; Horesh, A.; Kulkarni, S. R.; Corsi, A.; Quimby, R. M.; Gehrels, N.; Nugent, P. E.; Kasliwal, M. M.; Bildsten, L.; Poznanski, D.

    2013-01-01

    The optical light curve of some supernovae (SNe) may be powered by the outward diffusion of the energy deposited by the explosion shock (the so-called shock breakout) in optically thick (τ ∼> 30) circumstellar matter (CSM). Recently, it was shown that the radiation-mediated and radiation-dominated shock in an optically thick wind must transform into a collisionless shock and can produce hard X-rays. The X-rays are expected to peak at late times, relative to maximum visible light. Here we report on a search, using Swift/XRT and Chandra, for X-ray emission from 28 SNe that belong to classes whose progenitors are suspected to be embedded in dense CSM. Our sample includes 19 Type IIn SNe, one Type Ibn SN, and eight hydrogen-poor superluminous SNe (SLSN-I such as SN 2005ap). Two SNe (SN 2006jc and SN 2010jl) have X-ray properties that are roughly consistent with the expectation for X-rays from a collisionless shock in optically thick CSM. However, the X-ray emission from SN 2006jc can also be explained as originating in an optically thin region. Thus, we propose that the optical light curve of SN 2010jl is powered by shock breakout in CSM. We suggest that two other events (SN 2010al and SN 2011ht) were too X-ray bright during the SN maximum optical light to be explained by the shock-breakout model. We conclude that the light curves of some, but not all, SNe IIn/Ibn are powered by shock breakout in CSM. For the rest of the SNe in our sample, including all of the SLSN-I events, our X-ray limits are not deep enough and were typically obtained too early (i.e., near the SN maximum light) for definitive conclusions about their nature. Late-time X-ray observations are required in order to further test whether these SNe are indeed embedded in dense CSM. We review the conditions required for a shock breakout in a wind profile. We argue that the timescale, relative to maximum light, for the SN to peak in X-rays is a probe of the column density and the density profile above the

  10. Shock wave emission from laser-induced cavitation bubbles in polymer solutions.

    Science.gov (United States)

    Brujan, Emil-Alexandru

    2008-09-01

    The role of extensional viscosity on the acoustic emission from laser-induced cavitation bubbles in polymer solutions and near a rigid boundary is investigated by acoustic measurements. The polymer solutions consist of a 0.5% polyacrylamide (PAM) aqueous solution with a strong elastic component and a 0.5% carboxymethylcellulose (CMC) aqueous solution with a weak elastic component. A reduction of the maximum amplitude of the shock wave pressure and a prolongation of the oscillation period of the bubble were found in the elastic PAM solution. It might be caused by an increased resistance to extensional flow which is conferred upon the liquid by the polymer additive. In both polymer solutions, however, the shock pressure decays proportionally to r(-1) with increasing distance r from the emission centre.

  11. Type II successful supernovae, the anatomy of shocks: neutrino emission and the adiabatic index

    International Nuclear Information System (INIS)

    Kahana, S.; Baron, E.; Cooperstein, J.

    1983-01-01

    Hydrodynamic calculations of stellar collapse in Type II Supernova are described using a variable stiffness and compressibility for the nuclear equation of state at high density. Initial models employing a relatively small mass core with low central entropy are necessary to achieve viable shocks; near success the models are sensitive to both neutrino emission and the high density equation of state. The treatment of neutrino production and transport is sketched and recent results reported

  12. Broadband Shock Noise in Internally-Mixed Dual-Stream Jets

    Science.gov (United States)

    Bridges, James E.

    2009-01-01

    Broadband shock noise (BBSN) has been studied in some detail in single-flow jets and recently in dual-stream jets with separate flow exhaust systems. Shock noise is of great concern in these latter cases because of the noise created for the aircraft cabin by the underexpanded nozzle flow at cruise. Another case where shock noise is of concern is in the case of future supersonic aircraft that are expected to have bypass ratios small enough to justify internally mixed exhaust systems, and whose mission will push cycles to the point of imperfectly expanded flows. Dual-stream jets with internally mixed plume have some simplifying aspects relative to the separate flow jets, having a single shock structure given by the common nozzle pressure. This is used to separate the contribution of the turbulent shear layer to the broadband shock noise. Shock structure is held constant while the geometry and strength of the inner and merged shear layers are varying by changing splitter area ratio and core stream temperature. Flow and noise measurements are presented which document the efforts at separating the contribution of the inner shear layer to the broadband shock noise.

  13. GAMMA-RAY BURST REVERSE SHOCK EMISSION IN EARLY RADIO AFTERGLOWS

    Energy Technology Data Exchange (ETDEWEB)

    Resmi, Lekshmi [Indian Institute of Space Science and Technology, Trivandrum (India); Zhang, Bing, E-mail: l.resmi@iist.ac.in [Department of Physics and Astronomy, University of Nevada, Las Vegas (United States)

    2016-07-01

    Reverse shock (RS) emission from gamma-ray bursts is an important tool in investigating the nature of the ejecta from the central engine. If the magnetization of the ejecta is not high enough to suppress the RS, a strong RS emission component, usually peaking in the optical/IR band early on, would provide an important contribution to early afterglow light curve. In the radio band, synchrotron self-absorption may suppress early RS emission and also delay the RS peak time. In this paper, we calculate the self-absorbed RS emission in the radio band under different dynamical conditions. In particular, we stress that the RS radio emission is subject to self-absorption in both RSs and forward shocks (FSs). We calculate the ratio between the RS to FS flux at the RS peak time for different frequencies, which is a measure of the detectability of the RS emission component. We then constrain the range of physical parameters for a detectable RS, in particular the role of magnetization. We notice that unlike optical RS emission which is enhanced by moderate magnetization, moderately magnetized ejecta do not necessarily produce a brighter radio RS due to the self-absorption effect. For typical parameters, the RS emission component would not be detectable below 1 GHz unless the medium density is very low (e.g., n < 10{sup −3} cm{sup −3} for the interstellar medium and A {sub *} < 5 × 10{sup −4} for wind). These predictions can be tested using the afterglow observations from current and upcoming radio facilities such as the Karl G. Jansky Very Large Array, the Low-Frequency Array, the Five Hundred Meter Aperture Spherical Telescope, and the Square Kilometer Array.

  14. «We were shocked»: Soviet captivity and internment as acculturation stress

    Directory of Open Access Journals (Sweden)

    Наталья Викторовна Суржикова

    2009-09-01

    Full Text Available N.V. Surzhikova's article based at the specific source type - memories - covers social and cultural issues of the Soviet captivity and internment. The author analyses manifestation of cultural shock or a stress of acculturation that proceeded from the direct contact of the prisoners and interned persons with another cultural conditions as well as mechanisms and limits of their adaptation.

  15. A preventive maintenance model for leased equipment subject to internal degradation and external shock damage

    International Nuclear Information System (INIS)

    Zhou, Xiaojun; Wu, Changjie; Li, Yanting; Xi, Lifeng

    2016-01-01

    A periodic preventive maintenance modeling method is proposed for leased equipment with continuous internal degradation and stochastic external shock damage considered simultaneously, which can facilitate the equipment lessor to optimize the maintenance schedule for the same kind of equipment rented by different lessees. A novel interactive mechanism between the continuous internal degradation and the stochastic external shock damage is established on the hazard rate of the equipment with integrating the imperfect effect of maintenance. Two improvement factors are defined for the modeling of imperfect maintenance. The number of failures resulting from internal degradation and from external shocks are both mathematically deduced based on this interactive mechanism. The optimal preventive maintenance scheme is obtained by minimizing the cumulative maintenance cost throughout the lease period. Numerical example shows that the proposed preventive maintenance model not only can reflect the reliability status of the equipment but also can clearly distinguish between the impact from internal degradation and that from external shocks. - Highlights: • We propose an imperfect periodic preventive maintenance model for leased equipment. • It can distinguish between the impact from internal degradation and that from external shocks. • An internal–external interactive mechanism is proposed. • Two improvement factors are introduced into the modeling of imperfect maintenance. • The model is helpful for the PM scheduling of the same equipment rented by different lessees.

  16. International mobility in carbon dioxide emissions

    International Nuclear Information System (INIS)

    Duro, Juan Antonio

    2013-01-01

    In this paper, we analyse the evolution of international mobility in per capita CO 2 emissions for the period 1971–2007. This concept reveals the distribution's degree of entrenchment which is fundamentally different from other distribution concepts. In particular, we use several different synthetic mobility measures in order to capture the various perceptions of mobility proposed in the literature. This approach can be seen as complementary to the dynamics of distribution approach. The empirical analysis yields the following main results. First, the evolution observed varies according to the mobility index used. Second, when broader mobility indices are used, the most recent years analysed (i.e. 2000–2007) and the 1970s appear to be the most dynamic periods. Third, their decomposition reveals the major role played by the non-high income countries group. Fourth, the calculation of fictitious indices associated with the three major decomposition components of general mobility indicates that exchange (i.e. changes in position) and dispersion (i.e. distribution effects) have typically been the most important mobility factors. Finally, there does not seem to be a clear, convincing relationship between mobility and the evolution of inequality, which to a certain extent underscores the need to carry out a differential analysis for mobility. The results obtained have some implications in terms of analysis and environmental policy. - Highlights: ► The evolution of international mobility in per capita CO 2 emissions for the period 1971–2007 is analysed. ► Several different synthetic mobility measures are used for capturing the various perceptions of mobility. ► The mobility is high and, in a significant way, without impact on distribution. ► There does not seem to be a clear, convincing relationship between mobility and the evolution of inequality. ► The results obtained have some implications in terms of analysis and environmental policy

  17. Systematic search for very-high-energy gamma-ray emission from bow shocks of runaway stars

    Science.gov (United States)

    H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

    2018-04-01

    Context. Runaway stars form bow shocks by ploughing through the interstellar medium at supersonic speeds and are promising sources of non-thermal emission of photons. One of these objects has been found to emit non-thermal radiation in the radio band. This triggered the development of theoretical models predicting non-thermal photons from radio up to very-high-energy (VHE, E ≥ 0.1 TeV) gamma rays. Subsequently, one bow shock was also detected in X-ray observations. However, the data did not allow discrimination between a hot thermal and a non-thermal origin. Further observations of different candidates at X-ray energies showed no evidence for emission at the position of the bow shocks either. A systematic search in the Fermi-LAT energy regime resulted in flux upper limits for 27 candidates listed in the E-BOSS catalogue. Aim. Here we perform the first systematic search for VHE gamma-ray emission from bow shocks of runaway stars. Methods: Using all available archival H.E.S.S. data we search for very-high-energy gamma-ray emission at the positions of bow shock candidates listed in the second E-BOSS catalogue release. Out of the 73 bow shock candidates in this catalogue, 32 have been observed with H.E.S.S. Results: None of the observed 32 bow shock candidates in this population study show significant emission in the H.E.S.S. energy range. Therefore, flux upper limits are calculated in five energy bins and the fraction of the kinetic wind power that is converted into VHE gamma rays is constrained. Conclusions: Emission from stellar bow shocks is not detected in the energy range between 0.14 and 18 TeV.The resulting upper limits constrain the level of VHE gamma-ray emission from these objects down to 0.1-1% of the kinetic wind energy.

  18. Spontaneous acoustic emission of a corrugated shock wave in the presence of a reflecting surface

    International Nuclear Information System (INIS)

    Wouchuk, J.G.; Lopez Cavada, J.

    2004-01-01

    An analytic model to study perturbation evolution in the space between a corrugated shock and a piston surface is presented. The conditions for stable oscillation patterns are obtained by looking at the poles of the exact Laplace transform. It is seen that besides the standard D'yakov-Kontorovich (DK) mode of oscillation, the shock surface can exhibit an additional finite set of discrete frequencies, due to the interaction with the piston which reflects sound waves from behind. The additional eigenmodes are excited when the shock is launched at t=0 + . The first eigenmode (the DK mode) is always present, if the Hugoniot curve has the correct slope in the V-p plane. However, the additional frequencies could be excited for strong enough shocks. The predictions of the model are verified for particular cases by studying a van der Waals gas, as in the work of Bates and Montgomery [Phys. Fluids 11, 462 (1999); Phys. Rev. Lett. 84, 1180 (2000)]. Only acoustic emission modes are considered

  19. Rear surface light emission measurements from laser-produced shock waves in clear and Al-coated polystyrene targets

    Science.gov (United States)

    McLean, E. A.; Deniz, A. V.; Schmitt, A. J.; Stamper, J. A.; Obenschain, S. P.; Lehecka, T.; Mostovych, A. N.; Seely, J.

    1999-08-01

    The Nike KrF laser, with its very uniform focal distributions, has been used at intensities near 10 14 W/cm 2 to launch shock waves in polystyrene targets. The rear surface visible light emission differed between clear polystyrene (CH) targets and targets with a thin (125 nm) Al coating on the rear side. The uncoated CH targets showed a relatively slowly rising emission followed by a sudden fall when the shock emerges, while the Al-coated targets showed a rapid rise in emission when the shock emerges followed by a slower fall, allowing an unambiguous determination of the time the shock arrived at the rear surface. A half-aluminized target allowed us to observe this difference in a single shot. The brightness temperature of both the aluminized targets and the non-aluminized targets was slightly below but close to rear surface temperature predictions of a hydrodynamic code. A discussion of preheat effects is given.

  20. Insoluble glycogen, a metabolizable internal adsorbent, decreases the lethality of endotoxin shock in rats

    Directory of Open Access Journals (Sweden)

    S. Sipka

    1997-01-01

    Full Text Available Insoluble glycogen is an enzymatically modified form of naturally occurring soluble glycogen with a great adsorbing capacity. It can be metabolized by phagocytes to glucose. In this study we used insoluble glycogen intravenously in the experimental endotoxin shock of rats. Wistar male rats were sensitized to endotoxin by Pb acetate. The survival of rats were compared in groups of animals endotoxin shock treated and non-treated with insoluble glycogen. Furthermore, we have determined in vitro the binding capacity of insoluble glycogen for endotoxin, tumour necrosis factor alpha, interleukin-1 and secretable phospholipase A2. Use of 10 mg/kg dose of insoluble glycogen could completely prevent the lethality of shock induced by LD50 quantity of endotoxin in rats. All animals treated survived. Insoluble glycogen is a form of ‘metabolizable internal adsorbents’. It can potentially be used for treatment of septic shock.

  1. Oil Shocks through International Transport Costs: Evidence from U.S. Business Cycles

    OpenAIRE

    Hakan Yilmazkuday

    2011-01-01

    The effects of oil shocks on output volatility through international transport costs are investigated in an open-economy DSGE model. Two versions of the model, with and without international transport costs, are structurally estimated for the U.S. economy by a Bayesian approach for moving windows of ten years. For model selection, the posterior odds ratios of the two versions are compared for each ten-year window. The version with international transport costs is selected during periods of hi...

  2. High energy emission of supernova sn 1987a. Cosmic rays acceleration in mixed shocks

    International Nuclear Information System (INIS)

    Lehoucq, Roland

    1992-01-01

    In its first part, this research thesis reports the study of the high energy emission of the sn 1987 supernova, based on a Monte Carlo simulation of the transfer of γ photons emitted during disintegration of radioactive elements (such as "5"6Ni, "5"6Co, "5"7Co and "4"4Ti) produced during the explosion. One of the studied problems is the late evolution (beyond 1200 days) of light curvature which is very different when it is powered by the radiation of a central object or by radioactivity. The second part reports the study of acceleration of cosmic rays in two-fluid shock waves in order to understand the different asymmetries noticed in hot spots of extragalactic radio-sources. This work comprises the resolution of structure equations of a shock made of a conventional fluid and a relativistic one, in presence or absence of a magnetic field [fr

  3. PROBING SHOCK BREAKOUT AND PROGENITORS OF STRIPPED-ENVELOPE SUPERNOVAE THROUGH THEIR EARLY RADIO EMISSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Keiichi, E-mail: keiichi.maeda@ipmu.jp [Kavli Institute for the Physics and Mathematics of the Universe (Kavli-IPMU), Todai Institutes for Advanced Study (TODIAS), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)

    2013-01-01

    We study properties of early radio emission from stripped-envelope supernovae (SNe; those of Type IIb/Ib/Ic). We suggest there is a sub-class of stripped-envelope SNe based on their radio properties, including the optically well-studied Type Ic SNe (SNe Ic) 2002ap and 2007gr, showing a rapid rise to a radio peak within {approx}10 days and reaching a low luminosity (at least an order of magnitude fainter than a majority of SNe IIb/Ib/Ic). They show a decline after the peak that is shallower than that of other stripped-envelope SNe while their spectral index is similar. We show that all these properties are naturally explained if the circumstellar material (CSM) density is low and therefore the forward shock is expanding into the CSM without deceleration. Since the forward shock velocity in this situation, as estimated from the radio properties, still records the maximum velocity of the SN ejecta following the shock breakout, observing these SNe in radio wavelengths provides new diagnostics on the nature of both the breakout and the progenitor which otherwise require a quite rapid follow-up in other wavelengths. The inferred post-shock breakout velocities of SNe Ic 2002ap and 2007gr are sub-relativistic, {approx}0.3c. These are higher than that inferred for SN II 1987A, in line with suggested compact progenitors. However, these are lower than expected for a Wolf-Rayet (W-R) progenitor. It may reflect an as yet unresolved nature of the progenitors just before the explosion, and we suggest that the W-R progenitor envelopes might have been inflated which could quickly reduce the maximum ejecta velocity from the initial shock breakout velocity.

  4. Per capita emissions of greenhouse gases and international trade

    International Nuclear Information System (INIS)

    Karman, D.; Baptiste, S.

    1994-01-01

    The role played by international trade in Canada's emissions of greenhouse gases is investigated. Data used in the study include Environment Canada greenhouse gas emission estimates for 1990, a Statistics Canada input-output model linking greenhouse gas emissions to economic activity in different sectors, and monetary statistics on imports and exports. Subject to some simplifying assumptions, it is estimated that nearly 20% of Canada's greenhouse gas emissions can be attributed to the production of commodities destined for export to other countries. If the same greenhouse gas emission intensities are assumed for Canada's imports, the greenhouse gas emissions due to Canada's net trade is nearly 7% of the 660 megatonnes of CO 2 equivalent emissions for 1990. Commodities from natural resource exploitation head the list of greenhouse gas emissions attributed to international trade, as expected from their large export volumes and large greenhouse gas emission intensities. 4 refs., 1 fig

  5. THE EFFECT OF TURBULENCE INTERMITTENCE ON THE EMISSION OF SOLAR ENERGETIC PARTICLES BY CORONAL AND INTERPLANETARY SHOCKS

    International Nuclear Information System (INIS)

    Kocharov, Leon; Laitinen, Timo; Vainio, Rami

    2013-01-01

    Major solar energetic particle events are associated with shock waves in solar corona and solar wind. Fast scattering of charged particles by plasma turbulence near the shock wave increases the efficiency of the particle acceleration in the shock, but prevents particles from escaping ahead of the shock. However, the turbulence energy levels in neighboring magnetic tubes of solar wind may differ from each other by more than one order of magnitude. We present the first theoretical study of accelerated particle emission from an oblique shock wave propagating through an intermittent turbulence background that consists of both highly turbulent magnetic tubes, where particles are accelerated, and quiet tubes, via which the accelerated particles can escape to the non-shocked solar wind. The modeling results imply that the presence of the fast transport channels penetrating the shock and cross-field transport of accelerated particles to those channels may play a key role in high-energy particle emission from distant shocks and can explain the prompt onset of major solar energetic particle events observed near the Earth's orbit

  6. THE EFFECT OF TURBULENCE INTERMITTENCE ON THE EMISSION OF SOLAR ENERGETIC PARTICLES BY CORONAL AND INTERPLANETARY SHOCKS

    Energy Technology Data Exchange (ETDEWEB)

    Kocharov, Leon [Sodankylä Geophysical Observatory (Oulu Unit), P.O. Box 3000, University of Oulu, FI-90014 Oulu (Finland); Laitinen, Timo [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Vainio, Rami [Department of Physics, P.O. Box 64, University of Helsinki, FI-00014 Helsinki (Finland)

    2013-11-20

    Major solar energetic particle events are associated with shock waves in solar corona and solar wind. Fast scattering of charged particles by plasma turbulence near the shock wave increases the efficiency of the particle acceleration in the shock, but prevents particles from escaping ahead of the shock. However, the turbulence energy levels in neighboring magnetic tubes of solar wind may differ from each other by more than one order of magnitude. We present the first theoretical study of accelerated particle emission from an oblique shock wave propagating through an intermittent turbulence background that consists of both highly turbulent magnetic tubes, where particles are accelerated, and quiet tubes, via which the accelerated particles can escape to the non-shocked solar wind. The modeling results imply that the presence of the fast transport channels penetrating the shock and cross-field transport of accelerated particles to those channels may play a key role in high-energy particle emission from distant shocks and can explain the prompt onset of major solar energetic particle events observed near the Earth's orbit.

  7. Shock Acceleration of Electrons and Synchrotron Emission from the Dynamical Ejecta of Neutron Star Mergers

    Science.gov (United States)

    Lee, Shiu-Hang; Maeda, Keiichi; Kawanaka, Norita

    2018-05-01

    Neutron star mergers (NSMs) eject energetic subrelativistic dynamical ejecta into circumbinary media. Analogous to supernovae and supernova remnants, the NSM dynamical ejecta are expected to produce nonthermal emission by electrons accelerated at a shock wave. In this paper, we present the expected radio and X-ray signals by this mechanism, taking into account nonlinear diffusive shock acceleration (DSA) and magnetic field amplification. We suggest that the NSM is unique as a DSA site, where the seed relativistic electrons are abundantly provided by the decays of r-process elements. The signal is predicted to peak at a few 100–1000 days after the merger, determined by the balance between the decrease of the number of seed electrons and the increase of the dissipated kinetic energy, due to the shock expansion. While the resulting flux can ideally reach the maximum flux expected from near-equipartition, the available kinetic energy dissipation rate of the NSM ejecta limits the detectability of such a signal. It is likely that the radio and X-ray emission are overwhelmed by other mechanisms (e.g., an off-axis jet) for an observer placed in a jet direction (i.e., for GW170817). However, for an off-axis observer, to be discovered once a number of NSMs are identified, the dynamical ejecta component is predicted to dominate the nonthermal emission. While the detection of this signal is challenging even with near-future facilities, this potentially provides a robust probe of the creation of r-process elements in NSMs.

  8. Social Skills Difficulty: Model of Culture Shock for International Graduate Students

    Science.gov (United States)

    Chapdelaine, Raquel Faria; Alexitch, Louise R.

    2004-01-01

    This study expanded and tested Furnham and Bochner's (1982) model of culture shock, employing a sample of 156 male international students in a Canadian university. Path analysis was used to assess the effects of cultural differences, size of co-national group, family status, cross-cultural experience, and social interaction with hosts on culture…

  9. International aviation emissions to 2025: Can emissions be stabilised without restricting demand?

    International Nuclear Information System (INIS)

    Macintosh, Andrew; Wallace, Lailey

    2009-01-01

    International aviation is growing rapidly, resulting in rising aviation greenhouse gas emissions. Concerns about the growth trajectory of the industry and emissions have led to calls for market measures such as emissions trading and carbon levies to be introduced to restrict demand and prompt innovation. This paper provides an overview of the science on aviation's contribution to climate change, analyses key trends in the industry since 1990, projects international civil aviation emissions to 2025 and analyses the emission intensity improvements that are necessary to offset rising international demand. The findings suggest international aviation carbon dioxide (CO 2 ) emissions will increase by more than 110 per cent between 2005 and 2025 (from 416 Mt to between 876 and 1013 Mt) and that it is unlikely emissions could be stabilised at levels consistent with risk averse climate targets without restricting demand

  10. A cocoon shock breakout as the origin of the γ-ray emission in GW170817

    Science.gov (United States)

    Gottlieb, Ore; Nakar, Ehud; Piran, Tsvi; Hotokezaka, Kenta

    2018-06-01

    The short Gamma-Ray Burst, GRB170817A, that followed the binary neutron star merger gravitational waves signal, GW170817, is not a usual sGRB. It is weaker by three orders of magnitude than the weakest sGRB seen before and its spectra, showing a hard early signal followed by a softer thermal spectrum, is unique. We show, first, that the γ-rays must have emerged from at least mildly relativistic outflow, implying that a relativistic jet was launched following the merger. We then show that the observations are consistent with the predictions of a mildly relativistic shock breakout: a minute γ-ray energy as compared with the total energy and a rather smooth light curve with a hard to soft evolution. We present here a novel analytic study and detailed numerical 2D and 3D relativistic hydrodynamic and radiation simulations that support the picture in which the observed γ-rays arose from a shock breakout of a cocoon from the merger's ejecta (Kasliwal et al. 2017). The cocoon can be formed by either a choked jet which does not generate a sGRB (in any direction) or by a successful jet which generates an undetected regular sGRB along the system's axis pointing away from us. Remarkably, for the choked jet model, the macronova signal produced by the ejecta (which is partially boosted to high velocities by the cocoon's shock) and the radio that is produced by the interaction of the shocked cocoon material with the surrounding matter, agree with the observed UV/optical/IR emission and with current radio observations. Finally, we discuss the possibility that the jet propagation within the ejecta may photodissociate some of of the heavy elements and may affect the composition of a fraction of ejecta and, in turn, the opacity and the early macronova light.

  11. Wind-embedded shocks in FASTWIND: X-ray emission and K-shell absorption

    Science.gov (United States)

    Carneiro, L. P.; Puls, J.; Sundqvist, J. O.; Hoffmann, T. L.

    2017-11-01

    EUV and X-ray radiation emitted from wind-embedded shocks can affect the ionization balance in the outer atmospheres of massive stars, and can also be the mechanism responsible for producing highly ionized atoms detected in the wind UV spectra. To investigate these processes, we implemented the emission from wind-embedded shocks and related physics into our atmosphere/spectrum synthesis code FASTWIND. We also account for the high energy absorption of the cool wind, by adding important K-shell opacities. Various tests justfying our approach have been described by Carneiro+(2016, A&A 590, A88). In particular, we studied the impact of X-ray emission on the ionization balance of important elements. In almost all the cases, the lower ionization stages (O iv, N iv, P v) are depleted and the higher stages (N v, O v, O vi) become enhanced. Moreover, also He lines (in particular He ii 1640 and He ii 4686) can be affected as well. Finally, we carried out an extensive discussion of the high-energy mass absorption coefficient, κν, regarding its spatial variation and dependence on T eff. We found that (i) the approximation of a radially constant κν can be justified for r >= 1.2R * and λ <= 18 Å, and also for many models at longer wavelengths. (ii) In order to estimate the actual value of this quantity, however, the He ii background needs to be considered from detailed modeling.

  12. Time resolved spectra in the infrared absorption and emission from shock heated hydrocarbons. [in interstellar medium

    Science.gov (United States)

    Bauer, S. H.; Borchardt, D. B.

    1990-01-01

    The wavelength range of a previously constructed multichannel fast recording spectrometer was extended to the mid-infrared. With the initial configuration, light intensities were recorded simultaneously with a silicon-diode array simultaneously at 20 adjacent wavelengths, each with a 20-micron time resolution. For studies in the infrared, the silicon diodes were replaced by a 20-element PbSe array of similar dimensions, cooled by a three-stage thermoelectric device. It is proposed that infrared emissions could be due to shock-heated low molecular-weight hydrocarbons. The full Swan band system appeared in time-integrated emission spectra from shock-heated C2H2; no soot was generated. At low resolution, the profiles on the high-frequency side of the black body maximum show no distinctive features. These could be fitted to Planck curves, with temperatures that declined with time from an initial high that was intermediate between T5 (no conversion) and T5(eq).

  13. Analysis of internal stress and anelasticity in the shock-compressed state from unloading wave data

    International Nuclear Information System (INIS)

    Johnson, J.N.; Lomdahl, P.S.; Wills, J.M.

    1991-01-01

    This paper reports on time resolved shock-wave measurements have often been used to infer microstructural behavior in crystalline solids. The authors apply this approach to an interpretation of the release-wave response of an aluminum alloy (6061-T6) as it is dynamically unloaded from a shock-compressed state of 20.7 GPa. The anelastic behavior in the initial portion of the unloading wave is attributed to the accumulation of internal stresses created by the shock process. Specific internal-stress models which are investigated are the double pile-up, the single pile-up, and single dislocation loops between pinning points. It is found that the essential characteristics of double and single pile-ups can be represented by a single dislocation between two pinned dislocations of like sing. Calculations of anelastic wave speeds at constant unloading strain rate are then compared with experimental data. The results suggest that the residual internal stress is due to pinned loops of density 10 15 M - 2 , and the viscous drag coefficient in the shock-compressed state is on the order of 10 - 7 MPa s (approximately two orders of magnitude greater than expected under ambient conditions)

  14. Shock waves and shock tubes; Proceedings of the Fifteenth International Symposium, Berkeley, CA, July 28-August 2, 1985

    International Nuclear Information System (INIS)

    Bershader, D.; Hanson, R.

    1986-01-01

    A detailed survey is presented of shock tube experiments, theoretical developments, and applications being carried out worldwide. The discussions explore shock tube physics and the related chemical, physical and biological science and technology. Extensive attention is devoted to shock wave phenomena in dusty gases and other multiphase and heterogeneous systems, including chemically reactive mixtures. Consideration is given to techniques for measuring, visualizing and theoretically modeling flowfield, shock wave and rarefaction wave characteristics. Numerical modeling is explored in terms of the application of computational fluid dynamics techniques to describing flowfields in shock tubes. Shock interactions and propagation, in both solids, fluids, gases and mixed media are investigated, along with the behavior of shocks in condensed matter. Finally, chemical reactions that are initiated as the result of passage of a shock wave are discussed, together with methods of controlling the evolution of laminar separated flows at concave corners on advanced reentry vehicles

  15. Report of 22nd International Symposium on Shock Waves; Dai 22 kai kokusai shogekiha symposium shusseki hokoku

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, K. [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science

    1999-11-05

    Outlined herein are the topics at the 22nd. International Symposium on Shock Waves, held in July 1999 in London. Prof. Takayama of Tohoku University gave an invited lecture on application of shock waves to medical area, stressing significance of shock waves on a human body. A total of 81 papers were presented from Japan. Number of Japanese papers and number of Japanese attendees both accounted for approximately 25%. The themes of these papers are centered by behavior of shock waves (e.g., propagation, reflection, and diffraction), extreme supersonic flows, interference between shock wave and boundary layer, aerodynamics (e.g., interference between vortex and shock wave), numerical simulation of shock wave phenomena, development of a new shock wave tube and measurement method, researches on elementary steps in chemical reactions, shock wave phenomena in condensed media and multi-phase media, shock wave noise produced while a high-speed train is running in a tunnel, and application of shock waves to industrial and medical areas. Japan contributes much to the application to medical area, and a method dispensing with injection is reported. Japan's aerospace-related researches include interference between shock wave and boundary layer, in which the real gas effect is taken into consideration, designs for protection from heat during the re-entry into the atmosphere, and construction of the world largest free-piston type wind tunnel. (NEDO)

  16. Time resolved spectra in the infrared absorption and emission from shock heated hydrocarbons

    Science.gov (United States)

    Bauer, S. H.; Borchardt, D. B.

    1990-07-01

    We have extended the wavelength range of our previously constructed multichannel, fast recording spectrometer to the mid-infrared. With the initial configuration, using a silicon-diode (photovoltaic) array, we recorded light intensities simultaneously at 20 adjacent wavelengths, each with 20 μs time resolution. For studies in the infrared the silicon diodes are replaced by a 20 element PbSe (photoconducting) array of similar dimensions (1×4 mm/element), cooled by a three-stage thermoelectric device. These elements have useful sensitivities over 1.0-6.7 μm. Three interchangeable gratings in a 1/4 m monochromator cover the following spectral ranges: 1.0-2.5 μm (resolution 33.6 cm-1) 2.5-4.5 μm (16.8 cm-1) 4.0-6.5 μm (16.7 cm-1). Incorporated in the new housing there are individually controlled bias-power sources for each detector, two stages of analogue amplification and a 20-line parallel output to the previously constructed digitizer, and record/hold computer. The immediate application of this system is the study of emission and absorption spectra of shock heated hydrocarbons-C2H2, C4H4 and C6H6-which are possible precursors of species that generate infrared emissions in the interstellar medium. It has been recently proposed that these radiations are due to PAH that emit in the infrared upon relaxation from highly excited states. However, it is possible that such emissions could be due to shock-heated low molecular-weight hydrocarbons, which are known to be present in significant abundances, ejected into the interstellar medium during stellar outer atmospheric eruptions. The full Swan band system appeared in time-integrated emission spectra from shock heated C2H2 (1% in Ar; T5eq~=2500K) no soot was generated. At low resolution the profiles on the high frequency side of the black body maximum show no distinctive features. These could be fitted to Planck curves, with temperatures that declined with time from an initial high that was intermediate between T5 (no

  17. EU emissions trading. The need for cap adjustment in response to external shocks and unexpected developments?

    Energy Technology Data Exchange (ETDEWEB)

    Diekmann, Jochen [DIW, Berlin (Germany)

    2012-11-15

    In this paper the advantages and disadvantages of the various adaptation options will be discussed from an economic perspective. Firstly, the criteria for identifying a need for potentially legitimate adaptation should be investigated. Furthermore, the issue of appropriate timely intervention points prior to or within the trading period will be discussed. In what periods and scenarios are adjustments to the cap worthwhile from an economic perspective? To what extent could minimum prices or price ranges make sense? What role could a strategic reserve play? By addressing these issues, it will be fundamentally discussed as to how the emissions trading scheme could be further developed and strengthened by greater flexibility. After a brief characterisation of emissions trading in theory and practice in Chapter 2, Chapter 3 will identify potential external shocks and unexpected developments which may impair the functioning of an emissions trading scheme. The current problems of cap setting for the third trading period of the EU ETS will be described in Chapter 4. Against this background, cap adjustments will be discussed in Chapter 5, minimum and maximum prices in Chapter 6 and strategic reserves in emissions trading in Chapter 7. The conclusions are summarised in Chapter 8.

  18. Study of turbulent and shock heated IGM gas with emission line spectroscopy in the Taffy galaxies

    Science.gov (United States)

    Joshi, Bhavin; Appleton, Phil; Blanc, Guillermo; Guillard, Pierre; Freeland, Emily; Peterson, Bradley; Alatalo, Katherine

    2018-01-01

    We present our results from optical IFU observations of the Taffy system (UGC 12914/15); named so because of the radio emission that stretches between the two galaxies. The Taffy galaxies are a major merger pair of galaxies where two gas-rich spiral galaxies have collided face on and passed through each other. The pair presents an unusually low IR luminosity (L_FIR ~ 4.5 x 10^{10} L_solar) and SFR (~ 0.23 M_solar / yr) for a typical post merger system. It was also found from Spitzer and Chandra observations that the Taffy "bridge" between the galaxies contains large amounts of warm molecular Hydrogen, >4.5 x 10^8 M_solar at 150-175K, and also shows soft X-ray emission. These results hinted at shock heating as a likely mechanism for heating the large amounts of gas in the Taffy bridge and keeping it at these temperatures, after other sources of heating are ruled out. The data we present in this paper are from the VIRUS-P instrument (now called GCMS) on the Harlan J. Smith 2.7m telescope at McDonald Observatory. We detect ionized gas all throughout the Taffy galaxies and in the bridge between them. Interestingly, the ionized gas shows emission line profiles with two velocity components almost all throughout the system. We also show evidence, through line diagnostic (BPT) diagrams, that the velocity component with lower velocity is likely excited by star formation whereas the velocity component with higher velocity is likely excited by shocks. We also find evidence for post-starburst populations in parts of the Taffy system.

  19. Time-resolved light emission of a, c, and r-cut sapphires shock-compressed to 65 GPa

    Science.gov (United States)

    Liu, Q. C.; Zhou, X. M.

    2018-04-01

    To investigate light emission and dynamic deformation behaviors, sapphire (single crystal Al2O3) samples with three crystallographic orientations (a, c, and r-cut) were shock-compressed by the planar impact method, with final stress ranges from 47 to 65 GPa. Emission radiance and velocity versus time profiles were simultaneously measured with a fast pyrometer and a Doppler pin system in each experiment. Wave profile results show anisotropic elastic-plastic transitions, which confirm the literature observations. Under final shock stress of about 52 GPa, lower emission intensity is observed in the r-cut sample, in agreement with the previous report in the literature. When final shock stress increases to 57 GPa and 65 GPa, spectral radiance histories of the r-cut show two stages of distinct features. In the first stage, the emission intensity of r-cut is lower than those of the other two, which agrees with the previous report in the literature. In the second stage, spectral radiance of r-cut increases with time at much higher rate and it finally peaks over those of the a and c-cut. These observations (conversion of intensified emission in the r-cut) may indicate activation of a second slip system and formation of shear bands which are discussed with the resolved shear stress calculations for the slip systems in each of the three cuts under shock compression.

  20. VLBI detection of the internal shocks in nova V959 Mon

    Science.gov (United States)

    Yang, J.; Paragi, Z.; O'Brien, T.; Chomiuk, L.; Linford, J. D.

    V959 Mon is a classical nova detected at GeV gamma-ray wavelengths on 2012 June 19. While classical novae are now routinely detected in gamma-rays, the origin of the shocks that produce relativistic particles has remained unknown. We carried out electronic European VLBI Network (e-EVN) observations that revealed a pair of compact synchrotron emission features in V959 Mon on 2012 Sep 18. Since synchrotron emission requires strong shocks as well, we identify these features as the location where the gamma rays were produced. We also detected the extended ejecta in the follow-up EVN observations. They expanded much faster in East-West direction than the compact knots detected in the aforementioned e-EVN measurements. By comparing the VLBI results with lower resolution images obtained using e-MERLIN and the VLA - as reported by Chomiuk et al. (2014) - it appears that 1) influenced by the binary orbit, the nova ejecta was highly asymmetric with a dense and slow outflow in the equatorial plane and low-density and faster ejecta along the poles; and 2) the VLBI knots were related to shocks formed in the interaction region of these outflows.

  1. 3-D Model of Broadband Emission from Supernova Remnants Undergoing Non-linear Diffusive Shock Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Shiu-Hang; Kamae, Tuneyoshi; Ellison, Donald C.

    2008-07-02

    We present a 3-dimensional model of supernova remnants (SNRs) where the hydrodynamical evolution of the remnant is modeled consistently with nonlinear diffusive shock acceleration occurring at the outer blast wave. The model includes particle escape and diffusion outside of the forward shock, and particle interactions with arbitrary distributions of external ambient material, such as molecular clouds. We include synchrotron emission and cooling, bremsstrahlung radiation, neutral pion production, inverse-Compton (IC), and Coulomb energy-loss. Boardband spectra have been calculated for typical parameters including dense regions of gas external to a 1000 year old SNR. In this paper, we describe the details of our model but do not attempt a detailed fit to any specific remnant. We also do not include magnetic field amplification (MFA), even though this effect may be important in some young remnants. In this first presentation of the model we don't attempt a detailed fit to any specific remnant. Our aim is to develop a flexible platform, which can be generalized to include effects such as MFA, and which can be easily adapted to various SNR environments, including Type Ia SNRs, which explode in a constant density medium, and Type II SNRs, which explode in a pre-supernova wind. When applied to a specific SNR, our model will predict cosmic-ray spectra and multi-wavelength morphology in projected images for instruments with varying spatial and spectral resolutions. We show examples of these spectra and images and emphasize the importance of measurements in the hard X-ray, GeV, and TeV gamma-ray bands for investigating key ingredients in the acceleration mechanism, and for deducing whether or not TeV emission is produced by IC from electrons or pion-decay from protons.

  2. The oil market and international agreements on CO2 emissions

    International Nuclear Information System (INIS)

    Berger, K.; Fimreite, Oe.; Golombek, R.; Hoel, M.

    1991-01-01

    In order to avoid a relatively large risk of dramatic adverse climatic changes during the next century, greenhouse gas emissions must be reduced significantly relative to present emissions. CO 2 is the most important greenhouse gas, so any international agreement will certainly cover CO 2 emissions. Any international agreement to reduce emissions of CO 2 is going to have a significant impact on the markets for fossil fuels. The analysis shows that is not only the amount of CO 2 emissions permitted in an agreement which matters for fossil fuel prices, but also the type of agreement. Two obvious forms of agreements, which under certain assumptions both are cost efficient, are (a) tradeable emission permits, and (b) an international CO 2 tax. If the fossil fuel markets were perfectly competitive, these two types of agreements would have the same effect on the producer price of fossil fuels. However, fossil fuel markets are not completely competitive. It is shown that, under imperfect competition, direct regulation of the ''tradeable quotas'' type tends to imply higher producer prices than an international CO 2 tax giving the same total CO 2 emissions. A numerical illustration of the oil market indicates that the difference in producer prices for the two types of CO 2 agreements is quite significant. 6 refs., 2 figs., 1 tab

  3. Trends in trace element emission legislation - an international overview

    Energy Technology Data Exchange (ETDEWEB)

    Sloss, L.L.

    2003-07-01

    Emissions of trace elements have decreased for a variety of reasons in many developed countries. However, the application of more successful control strategies in other industry sectors means that coal combustion is still a relatively important source of some trace elements, especially mercury. International and national legislation is increasingly being applied to trace element emissions. International programmes for trace element reduction are generally in the form of voluntary action plans with recommendations and targets for reduction. National legislation in Europe is commonly in the form of emission limits for specific sources. New legislation in the USA may take the form of best available technology or a minimum emission reduction requirement. It is also possible that mercury could be included in multi-pollutant emissions trading schemes. 52 refs., 4 tabs.

  4. HST-COS Observations on Hydrogen, Helium, Carbon, and Nitrogen Emission from the SN 1987A Reverse Shock

    Science.gov (United States)

    France, Kevin; McCray, Richard; Penton, Steven V.; Kirshner, Robert P.; Challis, Peter; Laming, J. Martin; Bouchet, Patrice; Chevalier, Roger; Garnavich, Peter M.; Fransson, Claes; hide

    2011-01-01

    We present the most sensitive ultraviolet observations of Supernova 1987 A to date. Imaging spectroscopy from the Hubble Space Telescope-Cosmic Origins Spectrograph shows many narrow (Delta v approximates 300 km/s) emission lines from the circumstellar ring, broad Delta v approximates 10-20 x 10(exp 3) km/s) emission lines from the reverse shock, and ultraviolet continuum emission. The high signal-to-noise ratio (>40 per resolution element) broad Ly-alpha emission is excited by soft X-ray and EUV heating of mostly neutral gas in the circumstellar ring and outer supernova debris. The ultraviolet continuum at lambda > 1350 A can be explained by H-I two-photon (2s(exp 2)S(sub 1/2)-l(exp 2)S(sub 1/2)) emission from the same region. We confirm our earlier, tentative detection of N V lambda 1240 emission from the reverse shock and present the first detections of broad He II lambda1640, C IV lambda 1550, and N IV ] lambda1486 emission lines from the reverse shock. The helium abundance in the high-velocity material is He/H = 0.14 +/- 0.06. The N V /H alpha line ratio requires partial ion-electron equilibration (T(sub e)/T(sub p) approximately equal to 0.14-0.35). We find that the N/C abundance ratio in the gas crossing the reverse shock is significantly higher than that in the circumstellar ring, a result that may be attributed to chemical stratification in the outer envelope of the supernova progenitor. The N/C abundance may have been stratified prior to the ring expUlsion, or this result may indicate continued CNO processing in the progenitor subsequent to the expUlsion of the circumstellar ring.

  5. Search for low-frequency diffuse radio emission around a shock in the massive galaxy cluster MACS J0744.9+3927

    Science.gov (United States)

    Wilber, A.; Brüggen, M.; Bonafede, A.; Rafferty, D.; Savini, F.; Shimwell, T.; van Weeren, R. J.; Botteon, A.; Cassano, R.; Brunetti, G.; De Gasperin, F.; Wittor, D.; Hoeft, M.; Birzan, L.

    2018-05-01

    Merging galaxy clusters produce low-Mach-number shocks in the intracluster medium. These shocks can accelerate electrons to relativistic energies that are detectable at radio frequencies. MACS J0744.9+3927 is a massive [M500 = (11.8 ± 2.8) × 1014 M⊙], high-redshift (z = 0.6976) cluster where a Bullet-type merger is presumed to have taken place. Sunyaev-Zel'dovich maps from MUSTANG indicate that a shock, with Mach number M = 1.0-2.9 and an extension of ˜200 kpc, sits near the centre of the cluster. The shock is also detected as a brightness and temperature discontinuity in X-ray observations. To search for diffuse radio emission associated with the merger, we have imaged the cluster with the LOw Frequency ARray (LOFAR) at 120-165 MHz. Our LOFAR radio images reveal previously undetected AGN emission, but do not show clear cluster-scale diffuse emission in the form of a radio relic nor a radio halo. The region of the shock is on the western edge of AGN lobe emission from the brightest cluster galaxy. Correlating the flux of known shock-induced radio relics versus their size, we find that the radio emission overlapping the shocked region in MACS J0744.9+3927 is likely of AGN origin. We argue against the presence of a relic caused by diffusive shock acceleration and suggest that the shock is too weak to accelerate electrons from the intracluster medium.

  6. Effect of continuous hemofiltration on internal environment and survival rate of severe heatstroke dogs with shock

    Directory of Open Access Journals (Sweden)

    Guang-ming CHEN

    2011-08-01

    Full Text Available Objective To explore the effect of continuous hemofiltration(CHF on internal environment and survival rate of severe heatstroke dogs with shock.Methods Sixteen healthy male dogs were randomly divided into heatshock group(HS group,n=8 and continuous hemofiltration group(CHF group,n=8.Severe heatstroke model was established by applying high temperature to whole body,and then the animals were removed from the heating cabin as soon as they presented manifestations of shock.Dogs of HS group were put into an ordinary environment,while dogs of CHF group received CHF treatment.The core temperature(Tc,mean arterial pressure(MAP,blood gas analysis,serum electrolytes and survival rate of dogs in two groups were observed.Results The time from heat exposure to shock was 107.0±28.5min and 111.4±22.2min in HS group and CHF group respectively(t=-0.354,P=0.729.The Tc in CHF group declined to normal level 15 to 30 minitues after CHF treatment,while the Tc in HS group remained at a level higher than that before heat exposure at 90min after shock.The Tc of two groups showed significant difference at each time point after shock(P < 0.01.The MAP of both groups was obviously lowered than that before heatstroke.The MAP of CHF group raised gradually 30 min after treatment,while the MAP of HS group rose very slowly,and it was significantly lower than that of CHF group at each time point after 45min(P < 0.05,P < 0.01.All the dogs in both groups manifested hyperventilation and respiratory alkalosis when shock appeared.After shock,respiratory alkalosis in HS group gradually became metabolic acidosis,with some animals manifested combined metabolic and respiratory acidosis because of respiratory decompensation,while the blood gas levels in CHF group recovered to normal gradually.The blood gas levels of two groups showed significant difference at each time point after shock(P < 0.05,P < 0.01.Hypernatremia,hyperchloraemia and hyperpotassaemia were found in all animals of both

  7. International shock-wave database project : report of the requirements workshop.

    Energy Technology Data Exchange (ETDEWEB)

    Aidun, John Bahram (Institute of Problems of chemical Physics of Russian Academy of Sciences); Lomonosov, Igor V. (Institute of Problems of chemical Physics of Russian Academy of Sciences); Levashov, Pavel R. (Joint Institute for High Temperatures of Russian Academy of Sciences)

    2012-03-01

    We report on the requirements workshop for a new project, the International Shock-Wave database (ISWdb), which was held October 31 - November 2, 2011, at GSI, Darmstadt, Germany. Participants considered the idea of this database, its structure, technical requirements, content, and principles of operation. This report presents the consensus conclusions from the workshop, key discussion points, and the goals and plan for near-term and intermediate-term development of the ISWdb. The main points of consensus from the workshop were: (1) This international database is of interest and of practical use for the shock-wave and high pressure physics communities; (2) Intermediate state information and off-Hugoniot information is important and should be included in ISWdb; (3) Other relevant high pressure and auxiliary data should be included to the database, in the future; (4) Information on the ISWdb needs to be communicated, broadly, to the research community; and (5) Operating structure will consist of an Advisory Board, subject-matter expert Moderators to vet submitted data, and the database Project Team. This brief report is intended to inform the shock-wave research community and interested funding agencies about the project, as its success, ultimately, depends on both of these groups finding sufficient value in the database to use it, contribute to it, and support it.

  8. The oil market and international agreements on CO2 emissions

    International Nuclear Information System (INIS)

    Berger, K.; Fimreite, O.; Golombek, R.; Hoel, M.

    1992-01-01

    According to most scientists, greenhouse gas emissions must be reduced significantly relative to current trends to avoid dramatic adverse climatic changes during the next century. CO 2 is the most important greenhouse gas, so any international agreement will certainly cover CO 2 emissions. Any international agreement to reduce emissions of CO 2 is going to have a significant impact on the markets for fossil fuels. The analysis shows that it is not only the amount of CO 2 emissions permitted in an agreement which matters for fossil fuel prices, but also the type of agreement. Two obvious forms of agreements, which under certain assumptions both are cost efficient, are (a) tradeable emission permits, and (b) an international CO 2 tax. If the fossil fuel markets were perfectly competitive, these two types of agreements would have the same effect on the producer price of fossil fuels. However, fossil fuel markets are not completely competitive. It is shown that, under imperfect competition, direct regulation of the 'tradeable quotas' type tends to imply higher producer prices and a larger efficiency loss than an international CO 2 tax giving the same total CO 2 emissions. A numerical illustration of the oil market indicates that the difference in producer prices for the two types of CO 2 agreements is quite significant. 6 refs., 2 figs., 2 tabs

  9. Studies of the jet in BL Lacertae. I. Recollimation shock and moving emission features

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, M. H.; Hovatta, T. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Meier, D. L. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Arshakian, T. G. [I. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln (Germany); Homan, D. C. [Department of Physics, Denison University, Granville, OH 43023 (United States); Kovalev, Y. Y. [Astro Space Center of Lebedev Physical Institute, Profsoyuznaya 84/32, 117997 Moscow (Russian Federation); Lister, M. L.; Richards, J. L. [Department of Physics and Astronomy, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907 (United States); Pushkarev, A. B.; Savolainen, T., E-mail: mhc@astro.caltech.edu [Max-Planck-Institut für Radioastronomie, Auf Dem Hügel 69, D-53121 Bonn (Germany)

    2014-06-01

    Parsec-scale VLBA images of BL Lac at 15 GHz show that the jet contains a permanent quasi-stationary emission feature 0.26 mas (0.34 pc projected) from the core, along with numerous moving features. In projection, the tracks of the moving features cluster around an axis at a position angle of –166.°6 that connects the core with the standing feature. The moving features appear to emanate from the standing feature in a manner strikingly similar to the results of numerical two-dimensional relativistic magneto-hydrodynamic (RMHD) simulations in which moving shocks are generated at a recollimation shock (RCS). Because of this, and the close analogy to the jet feature HST-1 in M87, we identify the standing feature in BL Lac as an RCS. We assume that the magnetic field dominates the dynamics in the jet, and that the field is predominantly toroidal. From this we suggest that the moving features are compressions established by slow and fast mode magneto-acoustic MHD waves. We illustrate the situation with a simple model in which the slowest moving feature is a slow-mode wave, and the fastest feature is a fast-mode wave. In the model, the beam has Lorentz factor Γ{sub beam}{sup gal}≈3.5 in the frame of the host galaxy and the fast mode wave has Lorentz factor Γ{sub Fwave}{sup beam}≈1.6 in the frame of the beam. This gives a maximum apparent speed for the moving features, β{sub app} = v{sub app}/c = 10. In this model the Lorentz factor of the pattern in the galaxy frame is approximately three times larger than that of the beam itself.

  10. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016.

    Science.gov (United States)

    Rhodes, Andrew; Evans, Laura E; Alhazzani, Waleed; Levy, Mitchell M; Antonelli, Massimo; Ferrer, Ricard; Kumar, Anand; Sevransky, Jonathan E; Sprung, Charles L; Nunnally, Mark E; Rochwerg, Bram; Rubenfeld, Gordon D; Angus, Derek C; Annane, Djillali; Beale, Richard J; Bellinghan, Geoffrey J; Bernard, Gordon R; Chiche, Jean-Daniel; Coopersmith, Craig; De Backer, Daniel P; French, Craig J; Fujishima, Seitaro; Gerlach, Herwig; Hidalgo, Jorge Luis; Hollenberg, Steven M; Jones, Alan E; Karnad, Dilip R; Kleinpell, Ruth M; Koh, Younsuck; Lisboa, Thiago Costa; Machado, Flavia R; Marini, John J; Marshall, John C; Mazuski, John E; McIntyre, Lauralyn A; McLean, Anthony S; Mehta, Sangeeta; Moreno, Rui P; Myburgh, John; Navalesi, Paolo; Nishida, Osamu; Osborn, Tiffany M; Perner, Anders; Plunkett, Colleen M; Ranieri, Marco; Schorr, Christa A; Seckel, Maureen A; Seymour, Christopher W; Shieh, Lisa; Shukri, Khalid A; Simpson, Steven Q; Singer, Mervyn; Thompson, B Taylor; Townsend, Sean R; Van der Poll, Thomas; Vincent, Jean-Louis; Wiersinga, W Joost; Zimmerman, Janice L; Dellinger, R Phillip

    2017-03-01

    To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012." A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development. The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable. The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions. Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.

  11. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016.

    Science.gov (United States)

    Rhodes, Andrew; Evans, Laura E; Alhazzani, Waleed; Levy, Mitchell M; Antonelli, Massimo; Ferrer, Ricard; Kumar, Anand; Sevransky, Jonathan E; Sprung, Charles L; Nunnally, Mark E; Rochwerg, Bram; Rubenfeld, Gordon D; Angus, Derek C; Annane, Djillali; Beale, Richard J; Bellinghan, Geoffrey J; Bernard, Gordon R; Chiche, Jean-Daniel; Coopersmith, Craig; De Backer, Daniel P; French, Craig J; Fujishima, Seitaro; Gerlach, Herwig; Hidalgo, Jorge Luis; Hollenberg, Steven M; Jones, Alan E; Karnad, Dilip R; Kleinpell, Ruth M; Koh, Younsuk; Lisboa, Thiago Costa; Machado, Flavia R; Marini, John J; Marshall, John C; Mazuski, John E; McIntyre, Lauralyn A; McLean, Anthony S; Mehta, Sangeeta; Moreno, Rui P; Myburgh, John; Navalesi, Paolo; Nishida, Osamu; Osborn, Tiffany M; Perner, Anders; Plunkett, Colleen M; Ranieri, Marco; Schorr, Christa A; Seckel, Maureen A; Seymour, Christopher W; Shieh, Lisa; Shukri, Khalid A; Simpson, Steven Q; Singer, Mervyn; Thompson, B Taylor; Townsend, Sean R; Van der Poll, Thomas; Vincent, Jean-Louis; Wiersinga, W Joost; Zimmerman, Janice L; Dellinger, R Phillip

    2017-03-01

    To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012". A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development. The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable. The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions. Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.

  12. Annals of the International Geophysical Year solar radio emission during the International Geophysical Year

    CERN Document Server

    Smerd, S F

    1969-01-01

    Annals of the International Geophysical Year, Volume 34: Solar Radio Emission During the International Geophysical Year covers the significant solar radio emission events observed during the International Geophysical Year (IGY). This book is composed of six chapters, and begins with a summary of tabulated quantities describing solar radio emission during the IGY. The tabulated figures illustrate the method of recording the position of radio sources on the sun, the use of symbols in describing the structure of bursts observed at single frequencies, and the different types used in a spectral

  13. The liability rules under international GHG emissions trading

    International Nuclear Information System (INIS)

    Zhong Xiang Zhang

    2001-01-01

    Article 17 of the Kyoto Protocol authorizes emissions trading, but the rules governing emissions trading have been deferred to subsequent conferences. In designing and implementing an international greenhouse gas (GHG) emissions trading scheme, assigning liability rules has been considered to be one of the most challenging issues. In general, a seller-beware liability works well in a strong enforcement environment. In the Kyoto Protocol, however, it may not always work. By contrast, a buyer-beware liability could be an effective deterrent to non-compliance, but the costs of imposing it are expected to be very high. To strike a middle ground, we suggest a combination of preventive measures with strong but feasible end-of-period punishments to ensure compliance with the Kyoto emissions commitments. Such measures aim to maximize efficiency gains from emissions trading and at the same time, to minimize over-selling risks. (author)

  14. Monitoring the Induction of Heat Shock Factor 1/Heat Shock Protein 70 Expression following 17-Allylamino-Demethoxygeldanamycin Treatment by Positron Emission Tomography and Optical Reporter Gene Imaging

    Directory of Open Access Journals (Sweden)

    Mikhail Doubrovin

    2012-01-01

    Full Text Available The cell response to proteotoxic cell stresses is mediated primarily through activation of heat shock factor 1 (HSF1. This transcription factor plays a major role in the regulation of the heat shock proteins (HSPs, including HSP70. We demonstrate that an [124I]iodide-pQHNIG70 positron emission tomography (PET reporter system that includes an inducible HSP70 promoter can be used to image and monitor the activation of the HSF1/HSP70 transcription factor in response to drug treatment (17-allylamino-demethoxygeldanamycin [17-AAG]. We developed a dual imaging reporter (pQHNIG70 for noninvasive imaging of the heat shock response in cell culture and living animals previously and now study HSF1/HSP70 reporter activation in both cell culture and tumor-bearing animals following exposure to 17-AAG. 17-AAG (10–1,000 nM induced reporter expression; a 23-fold increase was observed by 60 hours. Good correspondence between reporter expression and HSP70 protein levels were observed. MicroPET imaging based on [124I]iodide accumulation in pQHNIG70-transduced RG2 xenografts showed a significant 6.2-fold reporter response to 17-AAG, with a corresponding increase in tumor HSP70 and in tumor human sodium iodide symporter and green fluorescent protein reporter proteins. The HSF1 reporter system can be used to screen anticancer drugs for induction of cytotoxic stress and HSF1 activation both in vitro and in vivo.

  15. Liability rules for international trading of greenhouse gas emissions quotas

    DEFF Research Database (Denmark)

    Haites, E.; Missfeldt, F.

    2001-01-01

    To reduce the costs of mitigating greenhouse gas emissions in accordance with the Kyoto protocol, international trades of emissions quotas are allowed. The revenue from the sale of quotas may exceed the sanctions for non-compliance if these penalties are weak or poorly enforced. Under...... these circumstances emissions trading enables a country to benefit financially through non-compliance. To counter non-compliance due to trading a range of liability proposals have been suggested. Using a simple global model, we analyze the economic and environmental performance of these proposals for the first...

  16. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3).

    Science.gov (United States)

    Singer, Mervyn; Deutschman, Clifford S; Seymour, Christopher Warren; Shankar-Hari, Manu; Annane, Djillali; Bauer, Michael; Bellomo, Rinaldo; Bernard, Gordon R; Chiche, Jean-Daniel; Coopersmith, Craig M; Hotchkiss, Richard S; Levy, Mitchell M; Marshall, John C; Martin, Greg S; Opal, Steven M; Rubenfeld, Gordon D; van der Poll, Tom; Vincent, Jean-Louis; Angus, Derek C

    2016-02-23

    Definitions of sepsis and septic shock were last revised in 2001. Considerable advances have since been made into the pathobiology (changes in organ function, morphology, cell biology, biochemistry, immunology, and circulation), management, and epidemiology of sepsis, suggesting the need for reexamination. To evaluate and, as needed, update definitions for sepsis and septic shock. A task force (n = 19) with expertise in sepsis pathobiology, clinical trials, and epidemiology was convened by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine. Definitions and clinical criteria were generated through meetings, Delphi processes, analysis of electronic health record databases, and voting, followed by circulation to international professional societies, requesting peer review and endorsement (by 31 societies listed in the Acknowledgment). Limitations of previous definitions included an excessive focus on inflammation, the misleading model that sepsis follows a continuum through severe sepsis to shock, and inadequate specificity and sensitivity of the systemic inflammatory response syndrome (SIRS) criteria. Multiple definitions and terminologies are currently in use for sepsis, septic shock, and organ dysfunction, leading to discrepancies in reported incidence and observed mortality. The task force concluded the term severe sepsis was redundant. Sepsis should be defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. For clinical operationalization, organ dysfunction can be represented by an increase in the Sequential [Sepsis-related] Organ Failure Assessment (SOFA) score of 2 points or more, which is associated with an in-hospital mortality greater than 10%. Septic shock should be defined as a subset of sepsis in which particularly profound circulatory, cellular, and metabolic abnormalities are associated with a greater risk of mortality than with sepsis alone. Patients with septic shock

  17. BROAD N{sub 2}H{sup +} EMISSION TOWARD THE PROTOSTELLAR SHOCK L1157-B1

    Energy Technology Data Exchange (ETDEWEB)

    Codella, C.; Fontani, F.; Gómez-Ruiz, A.; Vasta, M. [INAF, Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, I-50125 Firenze (Italy); Viti, S. [Department of Physics and Astronomy, University College London, London (United Kingdom); Ceccarelli, C.; Lefloch, B.; Podio, L. [UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041 (France); Benedettini, M.; Busquet, G. [INAF, Istituto di Astrofisica e Planetologia Spaziali, via Fosso del Cavaliere 100, 00133 Roma (Italy); Caselli, P., E-mail: codella@rcetri.astro.it [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2013-10-10

    We present the first detection of N{sub 2}H{sup +} toward a low-mass protostellar outflow, namely, the L1157-B1 shock, at ∼0.1 pc from the protostellar cocoon. The detection was obtained with the IRAM 30 m antenna. We observed emission at 93 GHz due to the J = 1-0 hyperfine lines. Analysis of this emission coupled with HIFI CHESS multiline CO observations leads to the conclusion that the observed N{sub 2}H{sup +}(1-0) line originated from the dense (≥10{sup 5} cm{sup –3}) gas associated with the large (20''-25'') cavities opened by the protostellar wind. We find an N{sub 2}H{sup +} column density of a few 10{sup 12} cm{sup –2} corresponding to an abundance of (2-8) × 10{sup –9}. The N{sub 2}H{sup +} abundance can be matched by a model of quiescent gas evolved for more than 10{sup 4} yr, i.e., for more than the shock kinematical age (≅2000 yr). Modeling of C-shocks confirms that the abundance of N{sub 2}H{sup +} is not increased by the passage of the shock. In summary, N{sub 2}H{sup +} is a fossil record of the pre-shock gas, formed when the density of the gas was around 10{sup 4} cm{sup –3}, and then further compressed and accelerated by the shock.

  18. Evaluating carbon dioxide emissions in international trade of China

    International Nuclear Information System (INIS)

    Lin Boqiang; Sun Chuanwang

    2010-01-01

    China is the world's largest emitter of carbon dioxide (CO 2 ). As exports account for about one-third of China's GDP, the CO 2 emissions are related to not only China's own consumption but also external demand. Using the input-output analysis (IOA), we analyze the embodied CO 2 emissions of China's import and export. Our results show that about 3357 million tons CO 2 emissions were embodied in the exports and the emissions avoided by imports (EAI) were 2333 million tons in 2005. The average contribution to embodied emission factors by electricity generation was over 35%. And that by cement production was about 20%. It implies that the production-based emissions of China are more than the consumption-based emissions, which is evidence that carbon leakage occurs under the current climate policies and international trade rules. In addition to the call for a new global framework to allocate emission responsibilities, China should make great efforts to improve its energy efficiency, carry out electricity pricing reforms and increase renewable energy. In particular, to use advanced technology in cement production will be helpful to China's CO 2 abatement.

  19. Results of measurements of emission from internal combustion engines

    International Nuclear Information System (INIS)

    Dimitrovski, Mile; Jovanovska, Vangelica

    1999-01-01

    A mathematical model for solving the emission from internal combustion engines on the cross roads are made. The exhausted pipes from vehicles are substituted with a pipe in a centre of the cross road. This model is proved with measurement made on vehicles in the city of Bitola (Macedonia). (Author)

  20. 77 FR 33811 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2012-06-07

    ... 63 National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines; Proposed Rule #0;#0... Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source...

  1. A Cometary Bow Shock and Mid-Infrared Emission Variations Revealed in Spitzer Observations of HD 34078 and IC 405

    OpenAIRE

    France, Kevin; McCandliss, Stephan R.; Lupu, Roxana E.

    2006-01-01

    We present new infrared observations of the emission/reflection nebula IC 405 obtained with the Spitzer Space Telescope. Infrared images in the four IRAC bands (3.6, 4.5, 5.8, and 8.0 um) and two MIPS bands (24 and 70 um) are complemented by IRS spectroscopy (5-30 um) of two nebular filaments. The IRAC (8.0 um) and MIPS imaging shows evidence of a bow shock associated with the runaway O9.5V star, HD 34078, created by the interaction between the star and nebular material. The ratio of emission...

  2. International banking conglomerates and the transmission of lending shocks across borders

    OpenAIRE

    Gropp, Reint; Radev, Deyan

    2017-01-01

    We investigate how solvency and wholesale funding shocks to 84 OECD parent banks affect the lending of 375 foreign subsidiaries. We find that parent solvency shocks are more important than wholesale funding shocks for subsidiary lending. Furthermore, we find that parent undercapitalization does not affect the transmission of shocks, while wholesale shocks transmit to foreign subsidiaries of parents that rely primarily on wholesale funding. We also find that transmission is affected by the str...

  3. Investigation of external and internal shock in the stability of Indonesia’s financial system

    Directory of Open Access Journals (Sweden)

    Maulina Vinus

    2017-07-01

    Full Text Available The objective of this research is to develop a financial system stability index and analyze the internal and external factors that we expect to affect the stability of the Indonesian financial system. We measured the single model of financial system stability index (FSSI from year 2004M03 to2014M09 in Indonesia, and compiled a single quantitative measure based on aggregate internal factors and external factors to capture and predict the shocks of the financial system stability. Stability parameters were composed of composite indicators on different bases. In addition, we developed a comprehensive index component associated with the relevant market conditions, including banking soundness index, financial vulnerability index, and regional economic climate index. Results stated that US economic growth and economic growth of ASEAN countries positively affected financial stability. In addition, current account, exchange rate, inflation, interest rate were shown to negatively affect financial stability. The results of this study imply that internal factors have a strong influence on the financial stability. Therefore, the central bank should give a fast and correct response to the changes of external and internal financial environment, especially for internal factors through monetary policy.

  4. Cooperative Emissions Trading Game: International Permit Market Dominated by Buyers.

    Science.gov (United States)

    Honjo, Keita

    2015-01-01

    Rapid reduction of anthropogenic greenhouse gas emissions is required to mitigate disastrous impacts of climate change. The Kyoto Protocol introduced international emissions trading (IET) to accelerate the reduction of carbon dioxide (CO2) emissions. The IET controls CO2 emissions through the allocation of marketable emission permits to sovereign countries. The costs for acquiring additional permits provide buyers with an incentive to reduce their CO2 emissions. However, permit price has declined to a low level during the first commitment period (CP1). The downward trend in permit price is attributed to deficiencies of the Kyoto Protocol: weak compliance enforcement, the generous allocation of permits to transition economies (hot air), and the withdrawal of the US. These deficiencies created a buyer's market dominated by price-making buyers. In this paper, I develop a coalitional game of the IET, and demonstrate that permit buyers have dominant bargaining power. In my model, called cooperative emissions trading (CET) game, a buyer purchases permits from sellers only if the buyer forms a coalition with the sellers. Permit price is determined by bargaining among the coalition members. I evaluated the demand-side and supply-side bargaining power (DBP and SBP) using Shapley value, and obtained the following results: (1) Permit price is given by the product of the buyer's willingness-to-pay and the SBP (= 1 - DBP). (2) The DBP is greater than or equal to the SBP. These results indicate that buyers can suppress permit price to low levels through bargaining. The deficiencies of the Kyoto Protocol enhance the DBP, and contribute to the demand-side dominance in the international permit market.

  5. Role of local absorption on the X-ray emission from MHD accretion shocks in classical T Tauri stars

    Directory of Open Access Journals (Sweden)

    Bonito

    2014-01-01

    Full Text Available Accretion processes onto classical T Tauri stars (CTTSs are believed to generate shocks at the stellar surface due to the impact of supersonic downflowing plasma. Although current models of accretion streams provide a plausible global picture of this process, several aspects are still unclear. For example, the observed X-ray luminosity in accretion shocks is, in general, well below the predicted value. A possible explanation discussed in the literature is in terms of significant absorption of the emission due to the thick surrounding medium. Here we consider a 2D MHD model describing an accretion stream propagating through the atmosphere of a CTTS and impacting onto its chromosphere. The model includes all the relevant physics, namely the gravity, the thermal conduction, and the radiative cooling, and a realistic description of the unperturbed stellar atmosphere (from the chromosphere to the corona. From the model results, we synthesize the X-ray emission emerging from the hot slab produced by the accretion shock, exploring different configurations and strengths of the stellar magnetic field. The synthesis includes the local absorption by the thick surrounding medium and the Doppler shift of lines due to the component of plasma velocity along the line-of-sight. We explore the effects of absorption on the emerging X-ray spectrum, considering different inclinations of the accretion stream with respect to the observer. Finally we compare our results with the observations.

  6. Dynamics of a Pipeline under the Action of Internal Shock Pressure

    Science.gov (United States)

    Il'gamov, M. A.

    2017-11-01

    The static and dynamic bending of a pipeline in the vertical plane under the action of its own weight is considered with regard to the interaction of the internal pressure with the curvature of the axial line and the axisymmetric deformation. The pressure consists of a constant and timevarying parts and is assumed to be uniformly distributed over the entire span between the supports. The pipeline reaction to the stepwise increase in the pressure is analyzed in the case where it is possible to determine the exact solution of the problem. The initial stage of bending determined by the smallness of elastic forces as compared to the inertial forces is introduced into the consideration. At this stage, the solution is sought in the form of power series and the law of pressure variation can be arbitrary. This solution provides initial conditions for determining the further process. The duration of the inertial stage is compared with the times of sharp changes of the pressure and the shock waves in fluids. The structure parameters are determined in the case where the shock pressure is accepted only by the inertial forces in the pipeline.

  7. Virtual Instrument for Emissions Measurement of Internal Combustion Engines

    Science.gov (United States)

    Pérez, Armando; Montero, Gisela; Coronado, Marcos; García, Conrado; Pérez, Rubén

    2016-01-01

    The gases emissions measurement systems in internal combustion engines are strict and expensive nowadays. For this reason, a virtual instrument was developed to measure the combustion emissions from an internal combustion diesel engine, running with diesel-biodiesel mixtures. This software is called virtual instrument for emissions measurement (VIEM), and it was developed in the platform of LabVIEW 2010® virtual programming. VIEM works with sensors connected to a signal conditioning system, and a data acquisition system is used as interface for a computer in order to measure and monitor in real time the emissions of O2, NO, CO, SO2, and CO2 gases. This paper shows the results of the VIEM programming, the integrated circuits diagrams used for the signal conditioning of sensors, and the sensors characterization of O2, NO, CO, SO2, and CO2. VIEM is a low-cost instrument and is simple and easy to use. Besides, it is scalable, making it flexible and defined by the user. PMID:27034893

  8. Virtual Instrument for Emissions Measurement of Internal Combustion Engines.

    Science.gov (United States)

    Pérez, Armando; Ramos, Rogelio; Montero, Gisela; Coronado, Marcos; García, Conrado; Pérez, Rubén

    2016-01-01

    The gases emissions measurement systems in internal combustion engines are strict and expensive nowadays. For this reason, a virtual instrument was developed to measure the combustion emissions from an internal combustion diesel engine, running with diesel-biodiesel mixtures. This software is called virtual instrument for emissions measurement (VIEM), and it was developed in the platform of LabVIEW 2010® virtual programming. VIEM works with sensors connected to a signal conditioning system, and a data acquisition system is used as interface for a computer in order to measure and monitor in real time the emissions of O2, NO, CO, SO2, and CO2 gases. This paper shows the results of the VIEM programming, the integrated circuits diagrams used for the signal conditioning of sensors, and the sensors characterization of O2, NO, CO, SO2, and CO2. VIEM is a low-cost instrument and is simple and easy to use. Besides, it is scalable, making it flexible and defined by the user.

  9. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3)

    Science.gov (United States)

    Singer, Mervyn; Deutschman, Clifford S.; Seymour, Christopher Warren; Shankar-Hari, Manu; Annane, Djillali; Bauer, Michael; Bellomo, Rinaldo; Bernard, Gordon R.; Chiche, Jean-Daniel; Coopersmith, Craig M.; Hotchkiss, Richard S.; Levy, Mitchell M.; Marshall, John C.; Martin, Greg S.; Opal, Steven M.; Rubenfeld, Gordon D.; van der Poll, Tom; Vincent, Jean-Louis; Angus, Derek C.

    2016-01-01

    IMPORTANCE Definitions of sepsis and septic shock were last revised in 2001. Considerable advances have since been made into the pathobiology (changes in organ function, morphology, cell biology, biochemistry, immunology, and circulation), management, and epidemiology of sepsis, suggesting the need for reexamination. OBJECTIVE To evaluate and, as needed, update definitions for sepsis and septic shock. PROCESS A task force (n = 19) with expertise in sepsis pathobiology, clinical trials, and epidemiology was convened by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine. Definitions and clinical criteria were generated through meetings, Delphi processes, analysis of electronic health record databases, and voting, followed by circulation to international professional societies, requesting peer review and endorsement (by 31 societies listed in the Acknowledgment). KEY FINDINGS FROMEVIDENCE SYNTHESIS Limitations of previous definitions included an excessive focus on inflammation, the misleading model that sepsis follows a continuum through severe sepsis to shock, and inadequate specificity and sensitivity of the systemic inflammatory response syndrome (SIRS) criteria. Multiple definitions and terminologies are currently in use for sepsis, septic shock, and organ dysfunction, leading to discrepancies in reported incidence and observed mortality. The task force concluded the term severe sepsis was redundant. RECOMMENDATIONS Sepsis should be defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. For clinical operationalization, organ dysfunction can be represented by an increase in the Sequential [Sepsis-related] Organ Failure Assessment (SOFA) score of 2 points or more, which is associated with an in-hospital mortality greater than 10%. Septic shock should be defined as a subset of sepsis in which particularly profound circulatory, cellular, and metabolic abnormalities are associated with a

  10. Proceedings of the First International Induced Gamma Emission Workshop

    International Nuclear Information System (INIS)

    Popescu, I.I.; Ur, C.A.

    1999-01-01

    The proceedings of the First International Induced Gamma Emission Workshop held on August 16-20, 1997 in Predeal, Romania contain 40 communications. These are bunched in the following 7 sections: 1. Opening session (8 papers); 2. Theory and Modelling (7 papers); 3. Pump Mechanisms (6 papers); 4. Pump Sources (3 papers); 5. Collective Effects (8 papers); 6. Nuclear Isomers (3 papers); 7. Moessbauer Effect (5 papers)

  11. A shock and wear system under environmental conditions subject to internal failures, repair, and replacement

    International Nuclear Information System (INIS)

    Montoro-Cazorla, Delia; Pérez-Ocón, Rafael

    2012-01-01

    A system in a random environment is considered. The influence of the external conditions is governed by a Markovian arrival process. The internal structure of failure and repair are governed by phase-type distributions. The maintenance is performed by policy N. Under these assumptions, the Markov process governing the system is constructed, and it is studied in transient and stationary regime, calculating the availability and the rate of occurrence of failures. The renewal process due to the replacements of the system is studied, and expressions for the number of replacements and for the number of repairs between replacements are calculated. This paper extends other previously published since it incorporates a shock arrival process with dependence among the interarrival times and the renewal process associated to the replacements. A numerical application illustrates the calculations.

  12. A DETAILED STUDY OF SPITZER-IRAC EMISSION IN HERBIG-HARO OBJECTS. I. MORPHOLOGY AND FLUX RATIOS OF SHOCKED EMISSION

    International Nuclear Information System (INIS)

    Takami, Michihiro; Karr, Jennifer L.; Chen, How-Huan; Lee, Hsu-Tai; Koh, Haegon

    2010-01-01

    We present a detailed analysis of Spitzer-IRAC images obtained toward six Herbig-Haro objects (HH 54/211/212, L 1157/1448, and BHR 71). Our analysis includes (1) comparisons of morphology between the four IRAC bands (3.6, 4.5, 5.8, and 8.0 μm) and H 2 1-0 S(1) at 2.12 μm for three out of six objects, (2) measurements of spectral energy distributions (SEDs) at selected positions, and (3) comparisons of these results with calculations of thermal H 2 emission at LTE (207 lines in four bands) and non-LTE (32-45 lines, depending on the particle for collisions). We show that the morphologies observed at 3.6 and 4.5 μm are similar to each other and to H 2 1-0 S(1). This is well explained by thermal H 2 emission at non-LTE if the dissociation rate is significantly larger than 0.002-0.02, allowing thermal collisions to be dominated by atomic hydrogen. In contrast, the 5.8 and 8.0 μm emission shows different morphologies from the others in some regions. This emission appears to be more enhanced at the wakes in bow shocks, or less enhanced in patchy structures in the jet. These tendencies are explained by the fact that thermal H 2 emission in the 5.8 and 8.0 μm band is enhanced in regions at lower densities and temperatures. Throughout, the observed similarities and differences in morphology between four bands and 1-0 S(1) are well explained by thermal H 2 emission. The observed SEDs are categorized into type-A, those in which the flux monotonically increases with wavelength, and type-B, those with excess emission at 4.5 μm. The type-A SEDs are explained by thermal H 2 emission, in particular with simple shock models with a power-law cooling function (Λ ∝ T s ). Our calculations suggest that the type-B SEDs require extra contaminating emission in the 4.5 μm band. The CO vibrational emission is the most promising candidate, and the other contaminants discussed to date (H I, [Fe II], fluorescent H 2 , and polycyclic aromatic hydrocarbon) are not likely to explain the

  13. National environmental targets and international emission reduction instruments

    International Nuclear Information System (INIS)

    Morthorst, P.E.

    2003-01-01

    According to the agreed burden sharing within the European Union the overall EU emission reduction target as agreed by in the Kyoto protocol is converted into national greenhouse gas reduction-targets for each of the member states. In parallel with national emission reduction initiatives common EU policies for emission reductions are considered. Currently discussed is the introduction of a market for tradable permits for CO 2 -emissions to achieve emission reductions within the power industry and other energy intensive industries. In parallel with this markets for green certificates to deploy renewable energy technologies seem to be appearing in a number of countries, among these Denmark, Italy, Sweden, Belgium (Flanders), England and Australia. Although these national initiatives for a green certificate market are fairly different, they could be a starting point for establishing a common EU certificate market. But interactions between national targets for greenhouse gas emissions and these international instruments for emission reduction are not a trivial matter, especially not seen in relation to the possible contributions of these instruments in achieving national GHG-reduction targets. The paper is split into three parts all taking a liberalised power market as starting point: The first part discusses the consequences of a general deployment of renewable energy technologies, using planning initiatives or national promotion schemes (feed-in tariffs). In the second part an international green certificate market is introduced into the liberalised power market context, substituting other national promotion schemes. Finally, in the third part a combination of an international green certificate market (TGC) and an international emission-trading scheme for CO 2 is analysed within the liberalised international power market set-up. The main conclusion is that neither the use of national renewable support schemes nor the introduction of a TGC-market into a liberalised

  14. High dynamic range emission measurements of shocked energetic materials: Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)

    Science.gov (United States)

    Bassett, Will P.; Dlott, Dana D.

    2016-06-01

    A new emission apparatus with high time resolution and high dynamic range was used to study shock-induced ignition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine in the form of ultrafine powder (4 ± 3 μm particle size), over a range of impact velocities (0.8-4.3 km s-1) and impact durations (2.5-16 ns). A graybody model was used to extract graybody emissivities and time-dependent temperatures from a few ns to 100 μs. The emission transients consisted of three parts: a 6700 K nanosecond burst during the shocks, a 4000-4500 K temperature spike near 0.3 μs followed by a ˜3300 K tail extending out to ˜100 μs. These temperatures varied remarkably little with impact velocity and duration, while the emission intensities and emissivities changed by over an order of magnitude. The emissivity changes were interpreted with a hot spot model, where hot spot temperatures reached a maximum of 6700 K and the hot spot volume fractions increased from 5% to 100% as impact velocity increased from 1 to 3 km s-1. Changing shock durations in the 2.5-16 ns range had noticeable effects on the microsecond emission. The 0.3 μs temperature spike was much smaller or absent with 2.5 ns shocks, but prominent with longer durations. An explanation for these effects was put forth that invoked the formation of carbon-rich clusters during the shock. In this view, cluster formation was minimal with 2.5 ns shocks, but longer-duration shocks produced increasingly larger clusters, and the 0.3 μs temperature spikes represented cluster ignition.

  15. Exploration of CdTe quantum dots as mesoscale pressure sensors via time-resolved shock-compression photoluminescent emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Zhitao [Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, Georgia 30332-0826 (United States); School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States); Banishev, Alexandr A.; Christensen, James; Dlott, Dana D. [School of Chemical Sciences and Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Lee, Gyuhyon; Scripka, David A.; Breidenich, Jennifer; Summers, Christopher J.; Thadhani, Naresh N., E-mail: naresh.thadhani@mse.gatech.edu [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States); Xiao, Pan [LNM, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0405 (United States); Zhou, Min [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0405 (United States)

    2016-07-28

    The nanometer size of CdTe quantum dots (QDs) and their unique optical properties, including size-tunable narrow photoluminescent emission, broad absorption, fast photoluminescence decay, and negligible light scattering, are ideal features for spectrally tagging the shock response of localized regions in highly heterogeneous materials such as particulate media. In this work, the time-resolved laser-excited photoluminescence response of QDs to shock-compression was investigated to explore their utilization as mesoscale sensors for pressure measurements and in situ diagnostics during shock loading experiments. Laser-driven shock-compression experiments with steady-state shock pressures ranging from 2.0 to 13 GPa were performed on nanocomposite films of CdTe QDs dispersed in a soft polyvinyl alcohol polymer matrix and in a hard inorganic sodium silicate glass matrix. Time-resolved photoluminescent emission spectroscopy was used to correlate photoluminescence changes with the history of shock pressure and the dynamics of the matrix material surrounding the QDs. The results revealed pressure-induced blueshifts in emitted wavelength, decreases in photoluminescent emission intensity, reductions in peak width, and matrix-dependent response times. Data obtained for these QD response characteristics serve as indicators for their use as possible time-resolved diagnostics of the dynamic shock-compression response of matrix materials in which such QDs are embedded as in situ sensors.

  16. Exploration of CdTe quantum dots as mesoscale pressure sensors via time-resolved shock-compression photoluminescent emission spectroscopy

    International Nuclear Information System (INIS)

    Kang, Zhitao; Banishev, Alexandr A.; Christensen, James; Dlott, Dana D.; Lee, Gyuhyon; Scripka, David A.; Breidenich, Jennifer; Summers, Christopher J.; Thadhani, Naresh N.; Xiao, Pan; Zhou, Min

    2016-01-01

    The nanometer size of CdTe quantum dots (QDs) and their unique optical properties, including size-tunable narrow photoluminescent emission, broad absorption, fast photoluminescence decay, and negligible light scattering, are ideal features for spectrally tagging the shock response of localized regions in highly heterogeneous materials such as particulate media. In this work, the time-resolved laser-excited photoluminescence response of QDs to shock-compression was investigated to explore their utilization as mesoscale sensors for pressure measurements and in situ diagnostics during shock loading experiments. Laser-driven shock-compression experiments with steady-state shock pressures ranging from 2.0 to 13 GPa were performed on nanocomposite films of CdTe QDs dispersed in a soft polyvinyl alcohol polymer matrix and in a hard inorganic sodium silicate glass matrix. Time-resolved photoluminescent emission spectroscopy was used to correlate photoluminescence changes with the history of shock pressure and the dynamics of the matrix material surrounding the QDs. The results revealed pressure-induced blueshifts in emitted wavelength, decreases in photoluminescent emission intensity, reductions in peak width, and matrix-dependent response times. Data obtained for these QD response characteristics serve as indicators for their use as possible time-resolved diagnostics of the dynamic shock-compression response of matrix materials in which such QDs are embedded as in situ sensors.

  17. Prospects for international trade in environmental services: An analysis of international carbon emission off-sets

    International Nuclear Information System (INIS)

    Swisher, J.N.

    1991-01-01

    This dissertation presents a case study analysis in which the costs to a US electric utility of reducing its carbon dioxide (CO 2 ) emissions are compared with the costs of carbon-saving forestry projects in Costa Rica and Guatemala. The results show that a large electric utility in the south-central US would find it relatively inexpensive, even profitable given a conducive regulatory treatment, to reduce its CO 2 emissions by a few percent over the next ten years, through direct investment in energy end-use efficiency improvements. In comparison, the costs of the forestry projects studied in Central America range from $1/TC to a worst-case value of about $55/TC, with most project costs between $5 and $13/TC, depending on the type of project, the climate, and the opportunity cost of land. The total amount of CO 2 storage potential is significant, about 100 million tons per country, but not enough to suggest that forestry can offset more than a few percent of global CO 2 emissions from fossil fuel use. These case studies suggest that international trade in the environmental service of reducing global CO 2 accumulation could have significant economic and ecological benefits. A transaction in which a utility pays for forestry projects in exchange for credit against an emission reduction policy is an example of an international carbon emission offset (ICEO). ICEO's could provide a currency for funding carbon-saving services as a way to comply with national policies to reduce CO 2 emissions, as long as compliance is allowed through investments in other countries. This type of North-South transfer is necessary to reconcile economic efficiency and international equity, because of the disparity between the national allocations of responsibility for greenhouse gas emissions and opportunities for emission reductions

  18. International Standards to Reduce Emissions from Marine Diesel Engines and Their Fuels

    Science.gov (United States)

    Overview of EPA coordination with International Maritime Organization including a list of all international regulations and materials related to emissions from marine compression-ignition (diesel) engines.

  19. International Students from Melbourne Describing Their Cross-Cultural Transitions Experiences: Culture Shock, Social Interaction, and Friendship Development

    Science.gov (United States)

    Belford, Nish

    2017-01-01

    Drawing from a study that explored how international students experience cross-cultural transitions after living and studying in Melbourne for a few years, this paper, in particular, examines the participants' experiences with culture shock, social interaction, and friendship development. The findings include narratives of their personal stories…

  20. Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock, 2012.

    Science.gov (United States)

    Dellinger, R P; Levy, Mitchell M; Rhodes, Andrew; Annane, Djillali; Gerlach, Herwig; Opal, Steven M; Sevransky, Jonathan E; Sprung, Charles L; Douglas, Ivor S; Jaeschke, Roman; Osborn, Tiffany M; Nunnally, Mark E; Townsend, Sean R; Reinhart, Konrad; Kleinpell, Ruth M; Angus, Derek C; Deutschman, Clifford S; Machado, Flavia R; Rubenfeld, Gordon D; Webb, Steven; Beale, Richard J; Vincent, Jean-Louis; Moreno, Rui

    2013-02-01

    To provide an update to the "Surviving Sepsis Campaign Guidelines for Management of Severe Sepsis and Septic Shock," last published in 2008. A consensus committee of 68 international experts representing 30 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict of interest policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independent of any industry funding. A stand-alone meeting was held for all subgroup heads, co- and vice-chairs, and selected individuals. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence from high (A) to very low (D) and to determine the strength of recommendations as strong (1) or weak (2). The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized. Recommendations were classified into three groups: (1) those directly targeting severe sepsis; (2) those targeting general care of the critically ill patient and considered high priority in severe sepsis; and (3) pediatric considerations. Key recommendations and suggestions, listed by category, include: early quantitative resuscitation of the septic patient during the first 6 h after recognition (1C); blood cultures before antibiotic therapy (1C); imaging studies performed promptly to confirm a potential source of infection (UG); administration of broad-spectrum antimicrobials therapy within 1 h of the recognition of septic shock (1B) and severe sepsis without septic shock (1C) as the goal of therapy; reassessment of antimicrobial therapy daily for de-escalation, when appropriate (1B

  1. Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock: 2012.

    Science.gov (United States)

    Dellinger, R Phillip; Levy, Mitchell M; Rhodes, Andrew; Annane, Djillali; Gerlach, Herwig; Opal, Steven M; Sevransky, Jonathan E; Sprung, Charles L; Douglas, Ivor S; Jaeschke, Roman; Osborn, Tiffany M; Nunnally, Mark E; Townsend, Sean R; Reinhart, Konrad; Kleinpell, Ruth M; Angus, Derek C; Deutschman, Clifford S; Machado, Flavia R; Rubenfeld, Gordon D; Webb, Steven A; Beale, Richard J; Vincent, Jean-Louis; Moreno, Rui

    2013-02-01

    To provide an update to the "Surviving Sepsis Campaign Guidelines for Management of Severe Sepsis and Septic Shock," last published in 2008. A consensus committee of 68 international experts representing 30 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict of interest policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independent of any industry funding. A stand-alone meeting was held for all subgroup heads, co- and vice-chairs, and selected individuals. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence from high (A) to very low (D) and to determine the strength of recommendations as strong (1) or weak (2). The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized. Some recommendations were ungraded (UG). Recommendations were classified into three groups: 1) those directly targeting severe sepsis; 2) those targeting general care of the critically ill patient and considered high priority in severe sepsis; and 3) pediatric considerations. Key recommendations and suggestions, listed by category, include: early quantitative resuscitation of the septic patient during the first 6 hrs after recognition (1C); blood cultures before antibiotic therapy (1C); imaging studies performed promptly to confirm a potential source of infection (UG); administration of broad-spectrum antimicrobials therapy within 1 hr of recognition of septic shock (1B) and severe sepsis without septic shock (1C) as the goal of therapy; reassessment of antimicrobial therapy daily for de

  2. CO2 emissions embodied in international trade: evidence for Spain

    International Nuclear Information System (INIS)

    Sanchez-Choliz, Julio; Duarte, Rosa

    2004-01-01

    The objective of this paper is to analyse the sectoral impacts that Spanish international trade relations have on present levels of atmospheric pollution using an input-output model. We try to evaluate the exports and imports of the Spanish economy in terms of the direct and indirect CO 2 emissions (CO 2 embodied) generated in Spain and abroad. The results show a slightly exporting behaviour in the Spanish economy which, nevertheless, hides important pollution interchanges. Moreover, the sectors transport material, mining and energy, non-metallic industries, chemical and metals are the most relevant CO 2 exporters and other services, construction, transport material and food the biggest CO 2 importers, and those whose final demands also embody more than 70% of the CO 2 emissions

  3. Combustion, detonation, shock waves. Proceedings of the Zel'dovich memorial - International conference on combustion. Volume 1

    International Nuclear Information System (INIS)

    Merzhanov, A.G.; Frolov, S.M.

    1995-01-01

    This book contains lectures by the experts in various fields of modern research in combustion, detonation and shock waves, presented at the Zel'dovich memorial - International conference on combustion dedicated to the 80-th birthday of academician Ya.B. Zel'dovich. There are eight chapters discussing the state-of-the-art in combustion kinetics, ignition and steady-state flame propagation, diffusion and heterogeneous combustion, turbulent combustion, unsteady combustion, detonation, combustion and detonation analogies, intense shock waves and extreme states of matter [ru

  4. The urgent need to internalize CO2 emission costs

    International Nuclear Information System (INIS)

    Goodland, R.; El Serafy, S.

    1998-01-01

    Despite growing manifestations of global warming and the commitment of most nations to move towards reducing greenhouse gas (GHG) emissions, a simple device that can be effective in reducing GHG emissions continues to be overlooked or even rejected. This is to acknowledge the fact that carbon emissions inflict global costs that are not borne by emitters. This paper advocates that all activities emitting or saving carbon emissions should internalize the carbon cost inflicted or avoided by new projects involving CO 2 . Considering the current wide range of carbon cost estimates, the paper recommends that a two-stage approach be adopted. Firstly, incorporate carbon costs in project analysis only theoretically in order to differentiate objectively among alternative designs involving carbon emissions of varying degrees. Different estimates of the costs of a ton of carbon would be used in order to test the sensitivity of rates of return to alternative carbon costs. While this process would have the effect of screening the allocation of scarce investment funds among projects that affect global warming in different degrees, it should be viewed as only a first step. Secondly, we advocate a rigorous process of passing through estimated carbon costs to the ultimate users of the services of carbon-emitting projects and processes. It is this ultimate process that will secure the urgently needed transition from the current dependence on fossil fuels to more benign sources of energy that would reduce climate-change risks. Since the time available is limited, the paper points out the urgency of these proposals that are crucial for sustainability

  5. Solar Flare Termination Shock and Synthetic Emission Line Profiles of the Fe xxi 1354.08 Å Line

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Lijia [Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA (United States); Li, Gang [Department of Space Science and CSPAR, University of Alabama in Huntsville, Huntsville, AL (United States); Reeves, Kathy; Raymond, John, E-mail: gang.li@uah.edu [Harvard-Smithsonian Center for Astrophysics, Boston, MA (United States)

    2017-09-01

    Solar flares are among the most energetic phenomena that occur in the solar system. In the standard solar flare model, a fast mode shock, often referred to as the flare termination shock (TS), can exist above the loop-top source of hard X-ray emissions. The existence of the TS has been recently related to spectral hardening of a flare’s hard X-ray spectra at energies >300 keV. Observations of the Fe xxi 1354.08 Å line during solar flares by the Interface Region Imaging Spectrograph ( IRIS ) spacecraft have found significant redshifts with >100 km s{sup −1}, which is consistent with a reconnection downflow. The ability to detect such a redshift with IRIS suggests that one may be able to use IRIS observations to identify flare TSs. Using a magnetohydrodynamic simulation to model magnetic reconnection of a solar flare and assuming the existence of a TS in the downflow of the reconnection plasma, we model the synthetic emission of the Fe xxi 1354.08 line in this work. We show that the existence of the TS in the solar flare may manifest itself in the Fe xxi 1354.08 Å line.

  6. The influence of oil price shocks on china’s macro-economy: A perspective of international trade

    Directory of Open Access Journals (Sweden)

    Dengke Chen

    2015-09-01

    Full Text Available This paper is aimed at investigating and understanding the relationship between China’s macro-economy and oil price from a new perspective—the international trade perspective. We find strong evidence to suggest that the increase of China’s price level, resulting from oil price shocks, is statistically less than that of its main trade partners’. This helps us to understand the confused empirical results estimated within the SVAR framework. More specifically, SVAR results suggest that China’s output level is positively correlated with the oil price. Positive correlation between China’s output and oil price shocks presumably results from the drop in China’s relative price induced by oil price shocks, which is inclined to stimulate China’s goods and service exports.

  7. Qualitative internal surface roughness classification using acoustic emission

    International Nuclear Information System (INIS)

    Mohd Hafizi Zohari; Mohd Hanif Saad

    2009-04-01

    This paper describes a novel new nondestructive method of qualitative internal surface roughness classification for pipes utilizing Acoustic Emission (AE) signal. Two different flowrate are introduced in a pipe obstructed using normally available components (e.g.: valve). The AE signal at suitable location from the obstruction are obtained and the peak amplitudes, RMS amplitude and energy of the AE signal are obtained. A dimensionless number, the Bangi Number, AB, is then calculated as a ratio of the AE parameters (peak amplitude, RMS amplitude or energy) in low flowrate measurement compared to the AE parameters in high flowrate measurement. It was observed that the Bangi Number, AB obtained can then be used to successfully discriminate between rough and smooth internal surface roughness. (author)

  8. Perpendicular relativistic shocks in magnetized pair plasma

    Science.gov (United States)

    Plotnikov, Illya; Grassi, Anna; Grech, Mickael

    2018-04-01

    Perpendicular relativistic (γ0 = 10) shocks in magnetized pair plasmas are investigated using two dimensional Particle-in-Cell simulations. A systematic survey, from unmagnetized to strongly magnetized shocks, is presented accurately capturing the transition from Weibel-mediated to magnetic-reflection-shaped shocks. This transition is found to occur for upstream flow magnetizations 10-3 10-2, it leaves place to a purely electromagnetic precursor following from the strong emission of electromagnetic waves at the shock front. Particle acceleration is found to be efficient in weakly magnetized perpendicular shocks in agreement with previous works, and is fully suppressed for σ > 10-2. Diffusive Shock Acceleration is observed only in weakly magnetized shocks, while a dominant contribution of Shock Drift Acceleration is evidenced at intermediate magnetizations. The spatial diffusion coefficients are extracted from the simulations allowing for a deeper insight into the self-consistent particle kinematics and scale with the square of the particle energy in weakly magnetized shocks. These results have implications for particle acceleration in the internal shocks of AGN jets and in the termination shocks of Pulsar Wind Nebulae.

  9. Molecular Line Emission from Multifluid Shock Waves. I. Numerical Methods and Benchmark Tests

    Science.gov (United States)

    Ciolek, Glenn E.; Roberge, Wayne G.

    2013-05-01

    We describe a numerical scheme for studying time-dependent, multifluid, magnetohydrodynamic shock waves in weakly ionized interstellar clouds and cores. Shocks are modeled as propagating perpendicular to the magnetic field and consist of a neutral molecular fluid plus a fluid of ions and electrons. The scheme is based on operator splitting, wherein time integration of the governing equations is split into separate parts. In one part, independent homogeneous Riemann problems for the two fluids are solved using Godunov's method. In the other, equations containing the source terms for transfer of mass, momentum, and energy between the fluids are integrated using standard numerical techniques. We show that, for the frequent case where the thermal pressures of the ions and electrons are Lt magnetic pressure, the Riemann problems for the neutral and ion-electron fluids have a similar mathematical structure which facilitates numerical coding. Implementation of the scheme is discussed and several benchmark tests confirming its accuracy are presented, including (1) MHD wave packets ranging over orders of magnitude in length- and timescales, (2) early evolution of multifluid shocks caused by two colliding clouds, and (3) a multifluid shock with mass transfer between the fluids by cosmic-ray ionization and ion-electron recombination, demonstrating the effect of ion mass loading on magnetic precursors of MHD shocks. An exact solution to an MHD Riemann problem forming the basis for an approximate numerical solver used in the homogeneous part of our scheme is presented, along with derivations of the analytic benchmark solutions and tests showing the convergence of the numerical algorithm.

  10. MOLECULAR LINE EMISSION FROM MULTIFLUID SHOCK WAVES. I. NUMERICAL METHODS AND BENCHMARK TESTS

    International Nuclear Information System (INIS)

    Ciolek, Glenn E.; Roberge, Wayne G.

    2013-01-01

    We describe a numerical scheme for studying time-dependent, multifluid, magnetohydrodynamic shock waves in weakly ionized interstellar clouds and cores. Shocks are modeled as propagating perpendicular to the magnetic field and consist of a neutral molecular fluid plus a fluid of ions and electrons. The scheme is based on operator splitting, wherein time integration of the governing equations is split into separate parts. In one part, independent homogeneous Riemann problems for the two fluids are solved using Godunov's method. In the other, equations containing the source terms for transfer of mass, momentum, and energy between the fluids are integrated using standard numerical techniques. We show that, for the frequent case where the thermal pressures of the ions and electrons are << magnetic pressure, the Riemann problems for the neutral and ion-electron fluids have a similar mathematical structure which facilitates numerical coding. Implementation of the scheme is discussed and several benchmark tests confirming its accuracy are presented, including (1) MHD wave packets ranging over orders of magnitude in length- and timescales, (2) early evolution of multifluid shocks caused by two colliding clouds, and (3) a multifluid shock with mass transfer between the fluids by cosmic-ray ionization and ion-electron recombination, demonstrating the effect of ion mass loading on magnetic precursors of MHD shocks. An exact solution to an MHD Riemann problem forming the basis for an approximate numerical solver used in the homogeneous part of our scheme is presented, along with derivations of the analytic benchmark solutions and tests showing the convergence of the numerical algorithm.

  11. Emission of OH* and CO2* during the high-temperature oxidation of acetone in reflected shock waves

    Science.gov (United States)

    Tereza, A. M.; Smirnov, V. N.; Vlasov, P. A.; Shumova, V. V.; Garmash, A. A.

    2018-01-01

    Experimental and kinetic modeling study of the ignition of a stoichiometric mixture of acetone with oxygen diluted by argon was carried out behind reflected shock waves within the temperature range of 1350-1810 K for the total mixture concentration [M 50] ~ 10-5 mol/cm3. Emission signals were recorded simultaneously for three different wavelengths: OH* (λ = 308 nm) and {{{CO}}}2* (λ1 = 365 nm; λ2 = 451 nm). It was revealed that the time it takes to reach the maximum of emission of OH* and {{{CO}}}2* is practically the same over the whole temperature range. At the same time, the emission profiles of {{{CO}}}2* after the maximum was attained, recorded at λ2 = 451 nm, differ noticeably from the profiles recorded at λ1 = 365 nm. For numerical modeling of the emission profiles of OH* and {{{CO}}}2* , the corresponding sets of excitation and quenching reactions available in the literature were used. In the course of our numerical simulations we succeeded in good agreement of our own experimental and simulation results on acetone ignition and the results available in the literature for conditions under consideration.

  12. Linking CO{sub 2} emissions from international shipping to the EU emissions trading scheme

    Energy Technology Data Exchange (ETDEWEB)

    Kaageson, Per [Nature Associates, Stockholm (Sweden)

    2009-09-15

    The objective of the report is to analyse the feasibility of a cap-and-trade system for CO{sub 2} emissions from international shipping linked to the European Emission Trading Scheme (ETS). The idea presented in the paper is to tie the permission for a ship to call at a port of a participating country to the vessels participation in a scheme for emissions trading under a common cap. The ship would be liable for emissions from fuel bunkered during, say, six months prior to a call at a participating port. With this design, emissions from the return voyages of ships involved in intercontinental traffic would automatically be covered, and shipowners and operators would gain nothing by calling at ports just outside the European Union. The geographical scope would thus be global, albeit limited to ships that call at ports of the European Union (and other participating states). The fuel consumption, that the surrendered CO{sub 2} allowances would have to match, could be declared by using the existing mandatory bunker delivery notes that all ships above 400 GT need to keep according to Regulation 18 of MARPOL Annex VI. The report discusses various ways for initial allocation of allowances and concludes that the least distorting method would be to sell them on auction and recycle all or most of the revenues to the shipping sector in a way that does not interfere with the objective of the trading scheme. In the case where Maritime Emissions Trading Scheme (METS) is initially limited to the ports of the European Union, at least 6 200 million ton less CO{sub 2} would be emitted over the 23 years between 2012 and 2035 compared to a business-as-usual scenario. However, a great part of this would be reductions in land-based sources paid indirectly by the shipping sector. (orig.)

  13. 75 FR 75937 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-12-07

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... internal combustion engines. Subsequently, the Administrator received two petitions for reconsideration... Any industry using a stationary 2211 Electric power reciprocating internal generation, combustion...

  14. 76 FR 12923 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2011-03-09

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... pollutants for existing stationary spark ignition reciprocating internal combustion engines. The final rule... reciprocating internal combustion generation, engine. transmission, or distribution. 622110 Medical and surgical...

  15. 77 FR 60341 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2012-10-03

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines AGENCY: Environmental Protection... Pollutants for Stationary Reciprocating Internal Combustion Engines to solicit comment on specific issues...

  16. 77 FR 37361 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2012-06-21

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines AGENCY: Environmental Protection... Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance...

  17. Potential early predictors for outcomes of experimental hemorrhagic shock induced by uncontrolled internal bleeding in rats.

    Directory of Open Access Journals (Sweden)

    Zaid A Abassi

    Full Text Available Uncontrolled hemorrhage, resulting from traumatic injuries, continues to be the leading cause of death in civilian and military environments. Hemorrhagic deaths usually occur within the first 6 hours of admission to hospital; therefore, early prehospital identification of patients who are at risk for developing shock may improve survival. The aims of the current study were: 1. To establish and characterize a unique model of uncontrolled internal hemorrhage induced by massive renal injury (MRI, of different degrees (20-35% unilateral nephrectomy in rats, 2. To identify early biomarkers those best predict the outcome of severe internal hemorrhage. For this purpose, male Sprague Dawley rats were anesthetized and cannulas were inserted into the trachea and carotid artery. After abdominal laparotomy, the lower pole of the kidney was excised. During 120 minutes, hematocrit, pO2, pCO2, base excess, potassium, lactate and glucose were measured from blood samples, and mean arterial pressure (MAP was measured through arterial tracing. After 120 minutes, blood loss was determined. Statistical prediction models of mortality and amount of blood loss were performed. In this model, the lowest blood loss and mortality rate were observed in the group with 20% nephrectomy. Escalation of the extent of nephrectomy to 25% and 30% significantly increased blood loss and mortality rate. Two phases of hemodynamic and biochemical response to MRI were noticed: the primary phase, occurring during the first 15 minutes after injury, and the secondary phase, beginning 30 minutes after the induction of bleeding. A Significant correlation between early blood loss and mean arterial pressure (MAP decrements and survival were noted. Our data also indicate that prediction of outcome was attainable in the very early stages of blood loss, over the first 15 minutes after the injury, and that blood loss and MAP were the strongest predictors of mortality.

  18. Experimental characterization of nanoparticles emissions during Laser Shock Processing of AA6061, AISI304 and Ti6Al4V

    Directory of Open Access Journals (Sweden)

    João F. Gomes

    2017-11-01

    Full Text Available This paper describes an experimental study on the emission of nanometric size particles during laser shock processing of metallic materials: stainless steel, aluminum and titanium alloys which are the most common ones processed by this technique. The emission of nanometric size particles was confirmed to consist of aggregates composed of smaller spherical particles in the range of 10-20 nm, covered by a small concentric “layer” probably of metal oxides. The analysis of the nanoparticles showed the presence of the main elements present in the tested alloys as well as high oxygen content, which is another indication of the presence of oxides of Fe, Al and Ti. The amount of emitted nanoparticles, showed considerable increases over the baseline measured for the working environment, and these increases correspond to the more intense pulses of the laser beam. The material density was seen to highly affect the quantity of emitted nanoparticles. During LSP of aluminium alloy (the lighter material a large quantity of nanoparticles was measured, while in LSP of stainless steel few nanoparticles were observed, and this is the denser material, among the three tested. Titanium alloy results in intermediate values. The study of these emissions is innovative and relevant for industrial environments where the manufacturing process is in use.

  19. Energy use and carbon emissions: Some international comparisons

    International Nuclear Information System (INIS)

    1994-03-01

    This report examines international energy use patterns, trends, and energy-related carbon emissions since 1970. The main focus of this study is on the developed countries, represented by the members of the organization for Economic Cooperation and Development (OECD). The study is organized as follows: (1) the OECD is placed in a world context; (2) aggregate-level information is then presented for an important part of the OECD, namely the Group of Seven (G-7) major industrialized countries (the US, Canada, Japan, the United Kingdom, France, Italy, and Germany -- defined in this report as western Germany only, except where indicated); and (3) individual economic sectors within the G-7 countries are broken out for detailed review

  20. Possibility of reducing CO2 emissions from internal combustion engines

    Science.gov (United States)

    Drabik, Dawid; Mamala, Jarosław; Śmieja, Michał; Prażnowski, Krzysztof

    2017-10-01

    Article defines on the possibility of reduction CO2 of the internal combustion engine and presents the analysis based on originally conducted studies. The increase in overall engine efficiency is sought after by all engineers dealing with engine construction, one of the major ways to reduce CO2 emissions is to increase the compression ratio. The application of the compression ratio that has been increased constructional in the engine will, on one hand, bring about the increase in the theoretical efficiency, but, on the other hand, require a system for pressure control at a higher engine load in order to prevent engine knocking. For the purposes of the article there was carried out a number of studies and compiled results, and on their basis determined what have a major impact on the reducing CO2.

  1. International trade and CO{sub 2} emissions; International handel og CO{sub 2}-udledning

    Energy Technology Data Exchange (ETDEWEB)

    Munksgaard, J.; Pade, L.L. [AKF, Copenhagen (Denmark); Lenzen, M. [Univ. of Sydney (Australia)

    2005-04-01

    International trade has an impact on national CO{sub 2} emissions and consequently on the ability to fulfil national CO{sub 2} reduction targets. Through goods and services traded in a globally interdependent world, the consumption in each country is linked to greenhouse gas emissions in other countries. It has been argued that in order to achieve equitable reduction targets, international trade has to be taken into account when assessing nations' responsibility for abating climate change. Especially for open economies such as Denmark, greenhouse gases embodied in international traded commodities can have a considerable influence on the national greenhouse gas responsibility. Founded in the concepts of 'producer CO{sub 2} responsibility', 'consumer CO{sub 2} responsibility' and 'CO{sub 2} trade balance' the aim of the present study has been to develop the single-region input-output model as used in a previous study into a multi-region input-output model in order to get a more realistic description of the production technologies actually used in the countries of imports. The study concludes that trade is the key to define CO{sub 2} responsibility on macroeconomics level and that imports should be founded in a multi-region model approach. The study also points at the need to consider the impact from foreign trade when negotiating national reduction targets and base line scenarios within the context of international climate agreements. (BA)

  2. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3)

    NARCIS (Netherlands)

    Singer, Mervyn; Deutschman, Clifford S.; Seymour, Christopher Warren; Shankar-Hari, Manu; Annane, Djillali; Bauer, Michael; Bellomo, Rinaldo; Bernard, Gordon R.; Chiche, Jean-Daniel; Coopersmith, Craig M.; Hotchkiss, Richard S.; Levy, Mitchell M.; Marshall, John C.; Martin, Greg S.; Opal, Steven M.; Rubenfeld, Gordon D.; van der Poll, Tom; Vincent, Jean-Louis; Angus, Derek C.

    2016-01-01

    IMPORTANCE Definitions of sepsis and septic shock were last revised in 2001. Considerable advances have since been made into the pathobiology (changes in organ function, morphology, cell biology, biochemistry, immunology, and circulation), management, and epidemiology of sepsis, suggesting the need

  3. Carbon emission offsets for aviation-generated emissions due to international travel to and from New Zealand

    International Nuclear Information System (INIS)

    Smith, Inga J.; Rodger, Craig J.

    2009-01-01

    International air transport emissions are not subject to liability under the Kyoto Protocol. However, pressure is mounting globally for international aviation to be included in post-Kyoto arrangements. In the absence of international collective action, a number of so-called carbon offsetting schemes have emerged that allow individual travellers and companies to compensate for their international air travel emissions. These schemes offer technological solutions, such as planting sink forests to sequester emissions. To consider the implications of future collective action, this paper presents a case study assessment of the physical feasibility of five schemes for all short duration journeys to and from New Zealand. This is the first comprehensive national-level case study assessment of competing offsetting options for international aviation emissions in the peer-reviewed literature. The CO 2 -e emissions produced by the air travel of international visitors to New Zealand, and for New Zealand residents travelling overseas, is calculated in this paper to be 7893 and 3948 Gg, respectively, in 2005. It is then shown that no single offsetting scheme targeted inside the country appears physically and/or politically realistic. This indicates the sheer size of these emissions, and the challenge that the international community faces for collective action on this matter. (author)

  4. Shock-related radio emission during coronal mass ejection lift-off?

    OpenAIRE

    Pohjolainen, S.

    2008-01-01

    Aims: We identify the source of fast-drifting decimetric-metric radio emission that is sometimes observed prior to the so-called flare continuum emission. Fast-drift structures and continuum bursts are also observed in association with coronal mass ejections (CMEs), not only flares. Methods: We analyse radio spectral features and images acquired at radio, H-alpha, EUV, and soft X-ray wavelengths, during an event close to the solar limb on 2 June 2003. Results: The fast-drifting decimetric-met...

  5. Are greenhouse gas emissions from international shipping a type of marine pollution?

    International Nuclear Information System (INIS)

    Shi, Yubing

    2016-01-01

    Whether greenhouse gas emissions from international shipping are a type of marine pollution is a controversial issue and is currently open to debate. This article examines the current treaty definitions of marine pollution, and applies them to greenhouse gas emissions from ships. Based on the legal analysis of treaty definitions and relevant international and national regulation on this issue, this article asserts that greenhouse gas emissions from international shipping are a type of ‘conditional’ marine pollution. - Highlights: • Greenhouse gas (GHG) emissions from international shipping are a type of ‘conditional’ marine pollution. • Shipping CO 2 may be treated as marine pollution under the 1972 London Dumping Convention. • Countries have adopted different legislation concerning the legal nature of GHG emissions from ships. • Regulating CO 2 emissions from ships as marine pollution may expedite global GHG emissions reduction.

  6. 75 FR 37732 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-06-30

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... hazardous air pollutants for existing stationary compression ignition reciprocating internal combustion... combustion engines. 40 CFR 63.6590 was amended by revising paragraphs (b)(1) and (3). Inadvertently...

  7. Emissions trading in transition economies: the link between international and domestic policy

    International Nuclear Information System (INIS)

    Evans, M.

    2003-01-01

    International emissions trading has the potential to significantly lower carbon mitigation costs and to promote environmentally friendly investment in transition economies. The design of domestic systems to complement international emissions trading will likely play a major role in emissions trading's effectiveness. This paper examines the benefits and challenges of proposed domestic systems and the related flows of emissions trading revenue in seller nations. The overwhelming majority of emissions available for sale will come from transition economies, which is why this article considers these countries as a group. Governments in countries such as Russia and Poland are interested in the potentially significant revenue they would reap from emissions trading, and some in those governments feel the money would best be used as general revenue for the government. Others argue that emissions trading should involve the private sector and other emitters in order to provide maximum incentives to reduce emissions and generate additional emissions trading revenue (the rules for international emissions trading explicitly allow this). Still others feel that special carbon mitigation funds would allow the government to maintain control yet stimulate additional emission reductions. Each policy contains its own set of challenges: stimulating further emission reductions, credibly monitoring emissions and emission reductions, or applying adequate fiscal accounting to the money flows

  8. Growth in emission transfers via international trade from 1990 to 2008.

    Science.gov (United States)

    Peters, Glen P; Minx, Jan C; Weber, Christopher L; Edenhofer, Ottmar

    2011-05-24

    Despite the emergence of regional climate policies, growth in global CO(2) emissions has remained strong. From 1990 to 2008 CO(2) emissions in developed countries (defined as countries with emission-reduction commitments in the Kyoto Protocol, Annex B) have stabilized, but emissions in developing countries (non-Annex B) have doubled. Some studies suggest that the stabilization of emissions in developed countries was partially because of growing imports from developing countries. To quantify the growth in emission transfers via international trade, we developed a trade-linked global database for CO(2) emissions covering 113 countries and 57 economic sectors from 1990 to 2008. We find that the emissions from the production of traded goods and services have increased from 4.3 Gt CO(2) in 1990 (20% of global emissions) to 7.8 Gt CO(2) in 2008 (26%). Most developed countries have increased their consumption-based emissions faster than their territorial emissions, and non-energy-intensive manufacturing had a key role in the emission transfers. The net emission transfers via international trade from developing to developed countries increased from 0.4 Gt CO(2) in 1990 to 1.6 Gt CO(2) in 2008, which exceeds the Kyoto Protocol emission reductions. Our results indicate that international trade is a significant factor in explaining the change in emissions in many countries, from both a production and consumption perspective. We suggest that countries monitor emission transfers via international trade, in addition to territorial emissions, to ensure progress toward stabilization of global greenhouse gas emissions.

  9. Greenhouse gas emissions from the international maritime transport of New Zealand's imports and exports

    International Nuclear Information System (INIS)

    Fitzgerald, Warren B.; Howitt, Oliver J.A.; Smith, Inga J.

    2011-01-01

    Greenhouse gas emissions from international maritime transport are exempt from liabilities under the Kyoto Protocol. Research into quantifying these emissions is ongoing, and influences policy proposals to reduce emissions. This paper presents a cargo-based analysis of fuel consumption and greenhouse gas emissions from New Zealand's international maritime transport of goods. Maritime transport moves 99.5% (by mass) of New Zealand's internationally traded products. It is estimated that 73% of visiting vessels' activity can be directly attributed to the movement of goods in and out of New Zealand. A cargo-based methodology was used to estimate that the international maritime transport of New Zealand's imports and exports consumed 2.5 million tonnes (Mt; 2.6 billion litres) of fuel during the year 2007, which generated 7.7 Mt of carbon dioxide (CO 2 ) emissions. Double-counting of emissions would occur if a similar method was applied to all New Zealand's trading partners. In contrast, since few large vessels refuel in New Zealand, the National Greenhouse Gas Inventory listed 2007 international maritime transportation emissions as 0.98 Mt of CO 2 , calculated from fuel bunkered for international transport. The results, therefore, show a significant difference between activity-based and bunker-fuel methodologies in quantifying New Zealand's emissions. International policy implications are discussed. - Research highlights: → Cargo-based analysis of GHG emissions from New Zealand's international maritime transport of goods. → 7.7 Mt of CO 2 estimated from international maritime transport of NZ's 2007 imports and exports. → 73% of visiting vessels' 2007 activity attributed to the movement of goods in and out of NZ. → The results were significantly different from NZ's GHG Inventory bunker-fuel derived emissions figure. → Detailed approach for international transport emissions regional/national assessments described.

  10. 76 FR 12863 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2011-03-09

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... combustion engines. The final rule was published on August 20, 2010. This direct final action amends certain... Emission Standards for Hazardous Air Pollutant for Stationary Reciprocating Internal Combustion Engines...

  11. UNUSUAL SHOCK-EXCITED OH MASER EMISSION IN A YOUNG PLANETARY NEBULA

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Hai-Hua; Shen, Zhi-Qiang [Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Rd, Shanghai, 200030 (China); Walsh, Andrew J. [International Centre for Radio Astronomy Research, Curtin University, GPO Box U1987, Perth WA 6845 (Australia); Gómez, José F. [Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía s/n, E-18008, Granada (Spain); Imai, Hiroshi [Department of Physics and Astronomy, Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065 (Japan); Green, James A. [SKA Organisation, Jodrell Bank Observatory, Lower Withington, Macclesfield, Cheshire SK11 9DL (United Kingdom); Dawson, Joanne R. [Department of Physics and Astronomy and MQ Research Centre in Astronomy, Astrophysics and Astrophotonics, Macquarie University, NSW 2109 (Australia); Ellingsen, Simon P. [School of Physical Sciences, Private Bag 37, University of Tasmania, Hobart 7001, TAS (Australia); Breen, Shari L. [Australia Telescope National Facility, CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia); Jones, Paul A.; Cunningham, Maria R. [School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Gibson, Steven J., E-mail: haihua.qiao@curtin.edu.au [Department of Physics and Astronomy, Western Kentucky University, 1906 College Heights Blvd, Bowling Green, KY 42101 (United States)

    2016-01-20

    We report on OH maser emission toward G336.644−0.695 (IRAS 16333−4807), which is a H{sub 2}O maser-emitting Planetary Nebula (PN). We have detected 1612, 1667, and 1720 MHz OH masers at two epochs using the Australia Telescope Compact Array, hereby confirming it as the seventh known case of an OH-maser-emitting PN. This is only the second known PN showing 1720 MHz OH masers after K 3−35 and the only evolved stellar object with 1720 MHz OH masers as the strongest transition. This PN is one of a group of very young PNe. The 1612 MHz and 1667 MHz masers are at a similar velocity to the 22 GHz H{sub 2}O masers, whereas the 1720 MHz masers show a variable spectrum, with several components spread over a higher velocity range (up to 36 km s{sup −1}). We also detect Zeeman splitting in the 1720 MHz transition at two epochs (with field strengths of ∼2 to ∼10 mG), which suggests the OH emission at 1720 MHz is formed in a magnetized environment. These 1720 MHz OH masers may trace short-lived equatorial ejections during the formation of the PN.

  12. On the International Transmission of Shocks: Micro-Evidence from Mutual Fund Portfolios

    OpenAIRE

    Claudio Raddatz; Sergio L. Schmukler

    2011-01-01

    Using micro-level data on mutual funds from different financial centers investing in equity and bonds, this paper analyzes how investors and managers behave and transmit shocks across countries. The paper shows that the volatility of mutual fund investments is quantitatively driven by investors through injections of capital into, or redemptions out of, each fund, and by managers changing the country weights and cash in their portfolios. Both investors and managers respond to returns and crise...

  13. Comparison report of RPV pressurised thermal shock - international comparative assessment study (PTS ICAS)

    International Nuclear Information System (INIS)

    1999-01-01

    A summary of the recently completed International Comparative Assessment Study of Pressurized- Thermal-Shock in Reactor Pressure Vessels (RPV PTS ICAS) is presented here to record the results in actual and comparative fashions. The ICAS Project brought together an international group of experts from research, utility and regulatory organizations to perform a comparative evaluation of analysis methodologies employed in the assessment of RPV integrity under PTS loading conditions. The Project was sponsored jointly by Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS), Koeln, Germany, and Oak Ridge National Laboratory (ORNL), USA, with assistance from the Organization for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA)/Committee on the Safety of Nuclear Installations (CSNI)/Principal Working Group (PWG) No. 3 (Integrity of Components and Structures). The ICAS Project grew out of a strong interest expressed by participants in the previous FALSIRE II Project to proceed with further evaluations of analysis methods used in RPV integrity assessment. A Launch Meeting for the ICAS Project was held at GRS-Koeln, during June 1996, where an emphasis was placed on identifying the different approaches to RPV integrity assessment being employed within the international nuclear technology community. Also a Problem Statement was drafted that defined a Western type four-loop RPV with cladding on the inner surface. Also, a detailed task matrix was defined that included a set of transient thermal-mechanical loading conditions postulated to result from loss-of-coolant accidents. The primary focus of the analyses was on the behaviour of relatively shallow cracks under these conditions. The assessment activities based on the Problem Statement were divided under three tasks: deterministic fracture mechanics (DFM), probabilistic fracture mechanics (PFM) and thermal-hydraulic mixing (THM). An Intermediate Workshop was held at OECD/NEA-Paris during June 1997, to

  14. A stock-flow consistent input-output model with applications to energy price shocks, interest rates, and heat emissions

    Science.gov (United States)

    Berg, Matthew; Hartley, Brian; Richters, Oliver

    2015-01-01

    By synthesizing stock-flow consistent models, input-output models, and aspects of ecological macroeconomics, a method is developed to simultaneously model monetary flows through the financial system, flows of produced goods and services through the real economy, and flows of physical materials through the natural environment. This paper highlights the linkages between the physical environment and the economic system by emphasizing the role of the energy industry. A conceptual model is developed in general form with an arbitrary number of sectors, while emphasizing connections with the agent-based, econophysics, and complexity economics literature. First, we use the model to challenge claims that 0% interest rates are a necessary condition for a stationary economy and conduct a stability analysis within the parameter space of interest rates and consumption parameters of an economy in stock-flow equilibrium. Second, we analyze the role of energy price shocks in contributing to recessions, incorporating several propagation and amplification mechanisms. Third, implied heat emissions from energy conversion and the effect of anthropogenic heat flux on climate change are considered in light of a minimal single-layer atmosphere climate model, although the model is only implicitly, not explicitly, linked to the economic model.

  15. The Political Economy of International Emissions Trading Scheme Choice

    DEFF Research Database (Denmark)

    Boom, Jan-Tjeerd; Svendsen, Jan Tinggard

    2000-01-01

    The Kyoto Protocol allows emission trade between the Annex B countries. We consider three schemes of emissions trading: government trading, permit trading and credit trading. The schemes are compared in a public choice setting focusing on group size and rent-seeking from interest groups. We find ...

  16. Miniature shock tube for laser driven shocks.

    Science.gov (United States)

    Busquet, Michel; Barroso, Patrice; Melse, Thierry; Bauduin, Daniel

    2010-02-01

    We describe in this paper the design of a miniature shock tube (smaller than 1 cm(3)) that can be placed in a vacuum vessel and allows transverse optical probing and longitudinal backside extreme ultraviolet emission spectroscopy in the 100-500 A range. Typical application is the study of laser launched radiative shocks, in the framework of what is called "laboratory astrophysics."

  17. Polarized radio outbursts in BL Lacertae. I. Polarized emission from a compact jet. II. The flux and polarization of a piston-driven shock

    International Nuclear Information System (INIS)

    Aller, H.D.; Aller, M.F.; Hughes, P.A.

    1985-01-01

    A second highly polarized burst in BL Lacertae observed in 1983 which has very similar properties to the earlier burst in 1981-82 is described, and it is shown that in both bursts the electric vector of the polarized emission is nearly parallel to the observed extended structure. A weak shock, moving relativistically close to the line of sight, appears to be a very effective means of producing the observed behavior. A simple model is developed to represent the outbursts as due to a piston-driven shock which exhibits polarized emission due to compression of the otherwise random magnetic field of a collimated flow. It is shown that the general features of total flux, polarized flux, and polarization position angle as a function of frequency and time can be understood in terms of such a model. 34 references

  18. China’s provincial CO2 emissions embodied in international and interprovincial trade

    International Nuclear Information System (INIS)

    Guo Ju’e; Zhang Zengkai; Meng Lei

    2012-01-01

    Trades create a mechanism of embodied CO 2 emissions transfer among regions, causing distortion on the total emissions. As the world’s second largest economy, China has a large scale of trade, which results in the serious problem of embodied CO 2 emissions transfer. This paper analyzes the characteristics of China’s CO 2 emissions embodied in international and interprovincial trade from the provincial perspective. The multi-regional Input–Output Model is used to clarify provincial CO 2 emissions from geographical and sectoral dimensions, including 30 provinces and 28 sectors. Two calculating principles (production accounting principle and consumption accounting principle, ) are applied. The results show that for international trade, the eastern area accounts for a large proportion in China’s embodied CO 2 emissions. The sectors as net exporters and importers of embodied CO 2 emissions belong to labor-intensive and energy-intensive industries, respectively. For interprovincial trade, the net transfer of embodied CO 2 emissions is from the eastern area to the central area, and energy-intensive industries are the main contributors. With the largest amount of direct CO 2 emissions, the eastern area plays an important role in CO 2 emissions reduction. The central and western areas need supportive policies to avoid the transfer of industries with high emissions. - Highlights: ► China’s embodied CO 2 emissions are analyzed from the provincial perspective. ► Eastern provinces have larger CO 2 emissions embodied in international trade. ► Embodied CO 2 emissions are mainly transferred from eastern area to central area. ► Coastal provinces play important roles in CO 2 emissions reduction. ► Inland provinces need supportive policies on emissions reduction.

  19. International Oil Price’s Impacts on Carbon Emission in China’s Transportation Industry

    Directory of Open Access Journals (Sweden)

    Guoxing Zhang

    2014-09-01

    Full Text Available Purpose: This paper analyses the impact mechanism of international oil price on the industrial carbon emission, and uses the partial least squares regression model to study international oil price’s impact on carbon emissions in China’s transportation industry.Design/methodology/approach: This paper chooses five independent variables of GDP, international oil price, private car population, passenger and freight transportation volume as impact factors to investigate industrial carbon emissions, the paper also analyses the impact mechanism of international oil price on the industrial carbon emission, and finally the paper uses the partial least squares regression model to study international oil price’s impact on carbon emissions in China’s transportation industry. With the independent variables’ historical data from 1994 to 2009 as a sample, the fitting of the industry carbon emissions is satisfying. And based on the data of 2011, the paper maintains the private car owning, passenger and freight transportation volume to study international oil prices’ impact on the industry carbon emissions at different levels of GDP.Findings: The results show that: with the same GDP growth, the industry carbon emissions increase with the rise in international oil prices, and vice versa, the industry carbon emissions decrease; and lastly when GDP increases to a certain extent, in both cases of international oil prices’ rise or fall, the industry carbon emissions will go up, and the industry carbon emissions increase even faster while the energy prices are rising.Practical implications: Limit the growth in private-vehicle ownership, change China's transport sector within the next short-term in the structure of energy consumption and put forward China's new energy, alternative energy sources and renewable energy application so as to weaken the dependence on international oil, and indirectly slowdown China's GDP growth rate, which are all possible

  20. Incentive-based regulation of CO2 emissions from international aviation

    International Nuclear Information System (INIS)

    Carlsson, F.; Hammar, H.

    2002-01-01

    We explore the possibilities of using incentive-based environmental regulations of CO 2 emissions from international civil aviation. In theory incentive-based instruments such as an emission charge or a tradable emission permit system are better regulations than so-called command-and-control regulations such as emission limits or technology standards. However, the implementation of these instruments is a complex issue. We therefore describe and discuss how an emission charge and a tradable emission permit system for international aviation should be designed in order to improve efficiency. We also compare these two types of regulations. In brief, we find that an emission charge and a tradable emission permit system in which the permits are auctioned have more or less the same characteristics. The main advantage of a tradable emission permit system is that the effect, in terms of emission reductions, is known. On the other hand, we show that under uncertainty an emission charge is preferred. The choice of regulation is a political decision and it does not seem likely that an environmental charge or a tradable emission permit system would be implemented without consideration of the costs of the regulation. Revenue-neutral charges or gratis distribution of permits would, for this reason, be realistic choices of regulations. However, such actions are likely to result in less stringent regulations and other negative welfare effects.(author)

  1. Are greenhouse gas emissions from international shipping a type of marine pollution?

    Science.gov (United States)

    Shi, Yubing

    2016-12-15

    Whether greenhouse gas emissions from international shipping are a type of marine pollution is a controversial issue and is currently open to debate. This article examines the current treaty definitions of marine pollution, and applies them to greenhouse gas emissions from ships. Based on the legal analysis of treaty definitions and relevant international and national regulation on this issue, this article asserts that greenhouse gas emissions from international shipping are a type of 'conditional' marine pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. The international transmission of monetary shocks in a dollarized economy: The case of USA and Lebanon

    Directory of Open Access Journals (Sweden)

    Goux François Jean

    2007-01-01

    Full Text Available We show that an American monetary shock wields an influence, though limited, over the Lebanese output in accordance with the literature advances. However, as we are waiting for a stronger transmission of U.S. short-term rates to Lebanese short-term rates, we notice that this transmission is weak in the first year. The result can be explained by the presence of pricing-to-market. After the end of the first year, we find the traditional result where the increase in the American interest rate is transmitted integrally to the Lebanese interest rate. We recognize this phenomenon as the dollarization effect.

  3. Great expectations. Can international emissions trading deliver an equitable climate regime?

    International Nuclear Information System (INIS)

    Baumert, Kevin A.; Perkaus, James F.; Kete, Nancy

    2003-01-01

    Climate change equity debates tend to focus on achieving a fair and global 'allocation' of emission rights among countries. Allocation proposals typically envision, if implicitly, two purposes for international emissions trading. First, trading is expected to serve as a cost-effective means of promoting compliance with emissions targets. Second, trading is posited as a means to generate financial transfers, typically from industrialized to transitioning and developing countries. This article investigates the common assumption that international emissions trading will effectively serve both of these purposes. We conclude that the two purposes might not be mutually supportive, and that efforts to use international emissions trading as a financial transfer mechanism may potentially undermine cost-effectiveness goals. International emissions trading on a global scale would create new risks in terms of both cost-effectiveness and environmental performance, some of which will be challenging to manage. In particular, uncertainties over market prices and trading eligibility, coupled with the costs of participation, may together be the Achilles heel of some allocation proposals that entail large financial transfers from industrialized to developing countries. Any proposal for an 'equitable' allocation of emission allowances, we conclude, must be cognizant of the risks and costs implied by a reliance on international emissions trading. We offer some suggestions to this end

  4. Developing a New Definition and Assessing New Clinical Criteria for Septic Shock For the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3)

    NARCIS (Netherlands)

    Shankar-Hari, Manu; Phillips, Gary S.; Levy, Mitchell L.; Seymour, Christopher W.; Liu, Vincent X.; Deutschman, Clifford S.; Angus, Derek C.; Rubenfeld, Gordon D.; Singer, Mervyn; Angus, Derek; Annane, Djilalli; Bauer, Michael; Bellomo, Rinaldo; Bernard, Gordon; Chiche, Jean-Daniel; Coopersmith, Craig; Deutschman, Cliff; Hotchkiss, Richard; Levy, Mitchell; Marshall, John; Martin, Greg; Opal, Steve; Rubenfeld, Gordon; Seymour, Christopher; van der Poll, Tom; Vincent, Jean-Louis

    2016-01-01

    IMPORTANCE Septic shock currently refers to a state of acute circulatory failure associated with infection. Emerging biological insights and reported variation in epidemiology challenge the validity of this definition. OBJECTIVE To develop a new definition and clinical criteria for identifying

  5. Atmospheric NLTE models for the spectroscopic analysis of blue stars with winds. III. X-ray emission from wind-embedded shocks

    Science.gov (United States)

    Carneiro, L. P.; Puls, J.; Sundqvist, J. O.; Hoffmann, T. L.

    2016-05-01

    Context. Extreme ultraviolet (EUV) and X-ray radiation emitted from wind-embedded shocks in hot, massive stars can affect the ionization balance in their outer atmospheres and can be the mechanism responsible for producing highly ionized atomic species detected in stellar wind UV spectra. Aims: To allow for these processes in the context of spectral analysis, we have implemented the emission from wind-embedded shocks and related physics into our unified, NLTE model atmosphere/spectrum synthesis code FASTWIND. Methods: The shock structure and corresponding emission is calculated as a function of user-supplied parameters (volume filling factor, radial stratification of shock strength, and radial onset of emission). We account for a temperature and density stratification inside the postshock cooling zones, calculated for radiative and adiabatic cooling in the inner and outer wind, respectively. The high-energy absorption of the cool wind is considered by adding important K-shell opacities, and corresponding Auger ionization rates have been included in the NLTE network. To test our implementation and to check the resulting effects, we calculated a comprehensive model grid with a variety of X-ray emission parameters. Results: We tested and verified our implementation carefully against corresponding results from various alternative model atmosphere codes, and studied the effects from shock emission for important ions from He, C, N, O, Si, and P. Surprisingly, dielectronic recombination turned out to play an essential role for the ionization balance of O iv/O v (particularly in dwarfs with Teff~ 45 000 K). Finally, we investigated the frequency dependence and radial behavior of the mass absorption coefficient, κν(r), which is important in the context of X-ray line formation in massive star winds. Conclusions: In almost all of the cases considered, direct ionization is of major influence because of the enhanced EUV radiation field, and Auger ionization only affects N vi

  6. LOW-VELOCITY SHOCKS TRACED BY EXTENDED SiO EMISSION ALONG THE W43 RIDGES: WITNESSING THE FORMATION OF YOUNG MASSIVE CLUSTERS

    International Nuclear Information System (INIS)

    Nguyen-Luong, Q.; Martin, P. G.; Motte, F.; Louvet, F.; Hill, T.; Hennemann, M.; Didelon, P.; Carlhoff, P.; Schilke, P.; Lesaffre, P.; Gusdorf, A.; Schneider, N.; Bontemps, S.; Duarte-Cabral, A.; Menten, K. M.; Wyrowski, F.; Bendo, G.; Roussel, H.; Bernard, J.-P.; Bronfman, L.

    2013-01-01

    The formation of high-mass stars is tightly linked to that of their parental clouds. Here, we focus on the high-density parts of W43, a molecular cloud undergoing an efficient event of star formation. Using a column density image derived from Herschel continuum maps, we identify two high-density filamentary clouds, called the W43-MM1 and W43-MM2 ridges. Both have gas masses of 2.1 × 10 4 M ☉ and 3.5 × 10 4 M ☉ above >10 23 cm -2 and within areas of ∼6 and ∼14 pc 2 , respectively. The W43-MM1 and W43-MM2 ridges are structures that are coherent in velocity and gravitationally bound, despite their large velocity dispersion measured by the N 2 H + (1-0) lines of the W43-HERO IRAM large program. Another intriguing result is that these ridges harbor widespread (∼10 pc 2 ) bright SiO (2-1) emission, which we interpret to be the result of low-velocity shocks (≤10 km s –1 ). We measure a significant relationship between the SiO (2-1) luminosity and velocity extent and show that it distinguishes our observations from the high-velocity shocks associated with outflows. We use state-of-the-art shock models to demonstrate that a small percentage (10%) of Si atoms in low-velocity shocks, observed initially in gas phase or in grain mantles, can explain the observed SiO column density in the W43 ridges. The spatial and velocity overlaps between the ridges of high-density gas and the shocked SiO gas suggest that ridges could be forming via colliding flows driven by gravity and accompanied by low-velocity shocks. This mechanism may be the initial conditions for the formation of young massive clusters

  7. Piston ring lubrication and hydrocarbon emissions from internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Froelund, K.

    1997-11-01

    Is it the intention with this project to improve the existing hydrocarbon emission model at the Institute by combining it with a model for predicting the piston ring lubrication. The piston ring lubrication model should be experimentally verified to ensure the validity of the model. The following items were the objectives of the current study: Develop a piston ring lubrication model. This implies the development of a ring-pack gas flow model; Examine the response of the piston ring lubrication model to changing engineer conditions. Especially, it would be interesting to look at the engine warm-up phase since this is the phase where the engine-out emissions are highest and where the commonly used three way catalyst is not capable of converting the engine-out emissions, thereby leading the engine-out emissions directly out in to the environment with the exhaust gases; In order to verify the piston ring lubrication model the lubricant distribution on the cylinder liner should be investigated experimentally. Here again it would be of great interesting to look at the engine warm-up phase; The piston ring lubrication model should be adjusted for application together with the new hydrocarbon emission model for SI-engines at the Institute in order to increase the accuracy of the latter; The piston ring lubrication model could be used for describing the transport of PAH`s in diesel engines. (EG)

  8. Frameworks for comparing emissions associated with production, consumption, and international trade.

    Science.gov (United States)

    Kanemoto, Keiichiro; Lenzen, Manfred; Peters, Glen P; Moran, Daniel D; Geschke, Arne

    2012-01-03

    While the problem of climate change is being perceived as increasingly urgent, decision-makers struggle to agree on the distribution of responsibility across countries. In particular, representatives from countries hosting emissions-intensive exporting industries have argued that the importers of emissions-intensive goods should bear the responsibility, and ensuing penalties. Indeed, international trade and carbon leakage appear to play an increasingly important role in the carbon emissions debate. However, definitions of quantities describing the embodiment of carbon emissions in internationally traded products, and their measurement, have to be sufficiently robust before being able to underpin global policy. In this paper we critically examine a number of emissions accounting concepts, examine whether the ensuing carbon balances are compatible with monetary trade balances, discuss their different interpretations, and highlight implications for policy. In particular, we compare the emissions embodied in bilateral trade (EEBT) method which considers total trade flows with domestic emission intensities, with the multi-regional input-output (MRIO) method which considers trade only into final consumption with global emission intensities. If consumption-based emissions of different countries were to be compared, we would suggest an MRIO approach because of the global emissions coverage inherent in this method. If trade-adjusted emission inventories were to be compared, we would suggest an EEBT approach due to the consistency with a monetary trade balance.

  9. International trade in carbon emission rights and basic materials: General equilibrium calculations for 2020

    International Nuclear Information System (INIS)

    Perroni, C.; Rutherford, T.F.

    1993-01-01

    Restrictions on CO 2 emissions affect international trade and the pattern of comparative advantage. This paper, based on calculations with a static general equilibrium model, suggests that international trade in carbon rights is a substitute for trade in energy-intensive goods, and thus international trading in carbon rights reduces sectoral effects of emission reductions. In our model, we surprisingly find that free riding by non-signatory countries may not render unilateral action ineffective. If the OECD unilaterally cuts global emissions by 5 per cent from 1990 levels by the year 2020, emission by non-OECD regions increase but offset less than 15 per cent of this cutback. Moreover, carbon taxes depress international oil prices and create incentives for increased trade in natural gas. 14 refs, 7 figs

  10. The Political Economy of International Emission Trading Scheme Choice: Empirical Evidence

    DEFF Research Database (Denmark)

    Boom, J.T.; Svendsen, Gert Tinggaard

    2000-01-01

    The Kyoto Protocol allows emissions trading. It does however not specify how this is to take place and the discussion on the design of an emissions trading scheme is ongoing. In this paper, we give some empirical evidence on the preference of industry and environmental organizations for internati...... for international emissions trading scheme. Since they may have an influence on decision makers, their opinion is important. Our conclusion is that both industry and environmental organizations prefer credit trading, although for widely different reasons....

  11. The Prevalence and Significance of Overt Disseminated Intravascular Coagulation in Patients with Septic Shock in the Emergency Department According to the Third International Consensus Definition

    Directory of Open Access Journals (Sweden)

    Byuk Sung Ko

    2016-11-01

    Full Text Available Background The prevalence and prognostic value of overt disseminated intravascular coagulation (DIC in patients with septic shock presenting to emergency departments (EDs is poorly understood, particularly following the release of a new definition of septic shock. The purpose of this study was to investigate the prevalence and prognostic value of DIC in septic shock. Methods We performed retrospective review of 391 consecutive patients with septic shock admitting to the ED of tertiary care, university-affiliated hospital during a 16-month. Septic shock was defined as fluid-unresponsive hypotension requiring vasopressor to maintain a mean arterial pressure of 65 mmHg or greater, and serum lactate level ≥ 2 mmol/L. Overt DIC was defined as an International Society on Thrombosis and Hemostasis (ISTH score ≥ 5 points. The primary endpoint was 28-day mortality. Results Of 391 patients with septic shock, 290 were included in the present study. The mean age was 65.6 years, the 28-day mortality rate was 26.9%, and the prevalence of overt DIC was 17.6% (n = 51 according to the ISTH score. The median DIC score was higher in non-survivors than in survivors (5.0 vs. 2.0, p = 0.001. Significant higher risk of mortality was observed in overt DIC patients compared to those without (28.2% vs. 13.7%, p = 0.005. Multivariable logistic regression analysis identified DIC to be independently associated with 28-day mortality (odds ratio, 2.689 [95% confidence interval, 1.390-5.201]. Conclusions Using the ISTH criteria of DIC, overt DIC in septic shock was found to be common among patients admitting to the ED and to be associated with higher mortality when it is accompanied with septic shock. Efforts are required to identify presence of overt DIC during the initial treatment of septic shock in patients presenting the the ED.

  12. Implementing the Kyoto protocol : why JI and CDM show more promise than international emissions trading

    NARCIS (Netherlands)

    Woerdman, E.

    The Kyoto protocol allows developed countries to achieve cost-effective greenhouse gas emission reductions abroad by means of international emissions trading (IET), joint implementation (JI) and the clean development mechanism (CDM). The article argues that JI and CDM projects will be more

  13. CRITERIA POLLUTANT EMISSIONS FROM INTERNAL COMBUSTION ENGINES IN THE NATURAL GAS INDUSTRY VOLUME 1. TECHNICAL REPORT

    Science.gov (United States)

    The report summarizes emission factors for criteria pollutants (NOx, CO, CH4, C2H6, THC, NMHC, and NMEHC) from stationary internal combustion engines and gas turbines used in the natural gas industry. The emission factors were calculated from test results from five test campaigns...

  14. Marine nitrous oxide emissions: An unknown liability for the international water sector

    International Nuclear Information System (INIS)

    Short, Michael D.; Peters, Gregory M.; Peirson, William L.; Ashbolt, Nicholas J.

    2013-01-01

    Highlights: • IPCC methodology for indirect marine nitrous oxide (N 2 O) emissions does not exist. • The water sector has an unknown N 2 O emissions liability from marine sewage disposal. • We model global sewage-nitrogen (N) emissions to coastal oceans during 1970–2050. • Emission factors for marine N 2 O will enable water sector N 2 O emissions accounting. • Industry benefits will include future revenue streams and better N emissions policy. -- Abstract: Reliable estimates of anthropogenic greenhouse gas (GHG) emissions are essential for setting effective climate policy at both the sector and national level. Current IPCC Guidelines for calculating nitrous oxide (N 2 O) emissions from sewage management are both highly uncertain and incomplete; a major methodological gap relates to the calculation of indirect N 2 O emissions from sewage disposed to marine environments. Here we apply a novel approach to estimate past and future global sewage-nitrogen emissions to coastal oceans and the potential marine N 2 O emissions linked to this nitrogen source. Then, by estimating the future cost associated with this largely uncharacterized emission source, we demonstrate the industry significance of developing a methodology for estimating N 2 O emissions from marine receiving environments. The capacity to accurately estimate, monitor and report GHG emissions has important consequences for informing future policy decisions regarding both mitigation and adaptation. A robust N 2 O emissions estimation methodology for sewage-nitrogen disposed to coastal oceans will allow the international water sector to more accurately and comprehensively inventory its N 2 O emissions. This will in turn allow for proper accounting of related future emissions liabilities while also enabling the sector to capitalize on any future economic returns linked to this source – providing much-needed capital to support the sector's future infrastructure and climate change adaptation challenges

  15. Emission factors of Austrian industry production and international comparison. Final report

    International Nuclear Information System (INIS)

    Turi, K.

    1997-05-01

    During the last few years a number of measures have been implemented in the Austrian industries to reduce air pollution and energy use. Therefore specific emissions in the various sectors were changed considerably during this period. The aim of this research project was to better characterize air pollutant emissions of the Austrian industry. Emission data as measured by the Austrian industry was compared with published emission factors from international literature. The results show that the emission factors of the Austrian industry are generally lower than literature emission factors. This is because on the one hand many older data from the literature do not reflect current state of the knowledge, and on the other hand because emission reduction measures and new technologies were introduced in the Austrian industry. (author)

  16. What will be the international rules for greenhouse gases emissions

    International Nuclear Information System (INIS)

    Godard, O.

    1993-01-01

    The formula of Marketable Permits set the problem for the basis of an international legitimacy. The economist discover again, concerning a market of very peculiar goods (and of a market to be created), the juridical and political bases of every exchange and hence of every economy. He then will call for jurists but also for historians because rules governing international relations are the product of an history

  17. An international research program on acid rain and emissions in Asia

    International Nuclear Information System (INIS)

    Foell, W.K.

    1992-01-01

    Strong economic and population growth will accelerate the rapid development of fossil fuel energy systems throughout Asia. If the present trends continue, by early next century Asian emissions of SO 2 will exceed the present emission levels in North America and Europe combined. In response to the concern that these emissions have the potential to cause significant damage in Asia, a group of international specialists has established a project on Acid Rain and Emissions in Asia. In the initial phase of this project, work is underway to develop an integrated assessment model to assist policy makers in evaluating options to reduce precursor emissions and to catalyze the process of international policy dialogue on acid rain in Asia. 8 refs., 3 figs., 1 tab

  18. The Effects of the Emission Cost on Route Choices of International Container Ships

    Directory of Open Access Journals (Sweden)

    Hyangsook Lee

    2016-01-01

    Full Text Available Maritime freight shipping has increased significantly and air pollution from international ships has grown accordingly, having serious environmental effects all over the world. This paper analyzes the effects of the emission cost on ocean route choices, focusing on international container ships. First, the paper formulates a freight network model that captures decisions and interactions of ocean carriers and port terminal operators in the maritime freight transport system. Then, the emission cost is calculated based on an activity-based approach as a component of the ocean transportation cost function. A case study is examined to find if the emission cost affects ocean route choices. The results indicate that the optimal ocean route and transportation cost are changed distinctively due to the emission cost. The research discusses how the emission cost plays a role in route changes and why ocean carriers have to consider these costs in their routing decisions.

  19. 78 FR 14457 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2013-03-06

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 60 and 63 [EPA-HQ-OAR-2008-0708, FRL-9756-4] RIN 2060-AQ58 National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines Correction In rule...

  20. Internal wave emission from baroclinic jets: experimental results

    Science.gov (United States)

    Borcia, Ion D.; Rodda, Costanza; Harlander, Uwe

    2016-04-01

    Large-scale balanced flows can spontaneously radiate meso-scale inertia-gravity waves (IGWs) and are thus in fact unbalanced. While flow-dependent parameterizations for the radiation of IGWs from orographic and convective sources do exist, the situation is less developed for spontaneously emitted IGWs. Observations identify increased IGW activity in the vicinity of jet exit regions. A direct interpretation of those based on geostrophic adjustment might be tempting. However, directly applying this concept to the parameterization of spontaneous imbalance is difficult since the dynamics itself is continuously re-establishing an unbalanced flow which then sheds imbalances by GW radiation. Examining spontaneous IGW emission in the atmosphere and validating parameterization schemes confronts the scientist with particular challenges. Due to its extreme complexity, GW emission will always be embedded in the interaction of a multitude of interdependent processes, many of which are hardly detectable from analysis or campaign data. The benefits of repeated and more detailed measurements, while representing the only source of information about the real atmosphere, are limited by the non-repeatability of an atmospheric situation. The same event never occurs twice. This argues for complementary laboratory experiments, which can provide a more focused dialogue between experiment and theory. Indeed, life cycles are also examined in rotating-annulus laboratory experiments. Thus, these experiments might form a useful empirical benchmark for theoretical and modeling work that is also independent of any sort of subgrid model. In addition, the more direct correspondence between experimental and model data and the data reproducibility makes lab experiments a powerful testbed for parameterizations. Here we show first results from a small rotating annulus experiments and we will further present our new experimental facility to study wave emission from jets and fronts.

  1. International Environmental Agreements: Emissions Trade, Safety Valves and Escape Clauses

    International Nuclear Information System (INIS)

    Karp, Larry; Zhao, Jinhua

    2010-01-01

    We explain how the structure of multi-national or multi-regional environmental agreements affect their chance of success. Trade in emissions permits has ambiguous and in some cases surprising effects on both the equilibrium level of abatement, and on the ability to persuade nations or regions to participate in environmental agreements. An escape clause policy and a safety valve policy have essentially the same properties when membership in environmental agreement is pre-determined, but they create markedly different effects on the incentives to join such an agreement. The two policies lead to a qualitative difference in the leverage that a potential member of the agreement exercises on other members

  2. International Emission Trading Systems: Trade Level and Political Acceptability

    DEFF Research Database (Denmark)

    Boom, J-T.; Svendsen, Gert Tinggaard

    1999-01-01

    , at the international level, industrial lobbyism was non-significant. Only the 'fossil fuel lobby' played a role. Third, at the national level, one could expect strong political opposition from industry lobbies in case quotas are actually to be distributed at firm level. But trade among countries may benefit industry...

  3. The fundamentals of the future international emissions trading system

    International Nuclear Information System (INIS)

    Stankeviciute, Loreta; Kitous, Alban; Criqui, Patrick

    2008-01-01

    The study aims to analyze the sectoral marginal abatements cost curves for a number of EU countries as well as to examine the efficiency aspects and the economic impacts for the major sectors of the ETS under different carbon market configurations in 2010 and 2020. To produce a consistent and realistic assessment, we employ sources such as GHG National Inventories, NAPs and POLES world energy model to constitute the sectoral base year and 2010, 2020 emission levels in different countries and regions. We then use the market analysis tool ASPEN, which enables to derive supply and demand from sectoral MACCs produced with the POLES model, and to evaluate the economic impacts on the carbon market participants. The paper shows that, in compliance with the Kyoto targets, the benefits of an enlarged carbon market are significant, since more than 50% of the abatement in the short term have to be achieved in ETS sectors, which may indeed use CDM or JI credits. A second major conclusion is that in 2020 the new flexibility margins provided by the adjustment of investments in new capacities compensate for the increase in pressure towards stronger emission reductions. This reduces the relative importance of the enlarged carbon market

  4. Shock Waves

    CERN Document Server

    Jiang, Z

    2005-01-01

    The International Symposium on Shock Waves (ISSW) is a well established series of conferences held every two years in a different location. A unique feature of the ISSW is the emphasis on bridging the gap between physicists and engineers working in fields as different as gas dynamics, fluid mechanics and materials sciences. The main results presented at these meetings constitute valuable proceedings that offer anyone working in this field an authoritative and comprehensive source of reference.

  5. CH4 and N2O emissions embodied in international trade of meat

    International Nuclear Information System (INIS)

    Caro, Dario; Caldeira, Ken; LoPresti, Anna; Davis, Steven J; Bastianoni, Simone

    2014-01-01

    Although previous studies have quantified carbon dioxide emissions embodied in products traded internationally, there has been limited attention to other greenhouse gases such as methane (CH 4 ) and nitrous oxide (N 2 O). Following IPCC guidelines, we estimate non-CO 2 emissions from beef, pork and chicken produced in 237 countries over the period 1990–2010, and assign these emissions to the country where the meat is ultimately consumed. We find that, between 1990 and 2010, an average of 32.8 Mt CO 2 -eq emissions (using 100 year global warming potentials) are embodied in beef, pork and chicken traded internationally. Further, over the 20 year period, the quantity of CO 2 -eq emissions embodied in traded meat increased by 19%. The largest trade flows of emissions embodied in meat were from Brazil and Argentina to Russia (2.8 and 1.4 Mt of CO 2 -eq, respectively). Trade flows within the European region are also substantial: beef and pork exported from France embodied 3.3 Mt and 0.4 Mt of CO 2 -eq, respectively. Emissions factor of meat production (i.e. CO 2 -eq emissions per kg of meat) produced depend on ambient temperature, development level, livestock category (e.g. cattle, pork, and chicken) and livestock management practices. Thus, trade may result in an overall increase of GHG emissions when meat-consuming countries import meat from countries with a greater emissions intensity of meat production rather than producing the meat domestically. Comparing the emissions intensity of meat production of trading partners, we assess trade flows according to whether they tend to reduce or increase global emissions from meat production. (letter)

  6. Impact of International Oil Price on Energy Conservation and Emission Reduction in China

    Directory of Open Access Journals (Sweden)

    Jian Chai

    2016-05-01

    Full Text Available In the context of “new normal” economy and frequent “haze”, the strategy of energy conservation and emission reduction aiming to lower costs and reduce pollution is currently still a major strategic direction in China and the world, and will remain so for some time in the future. This paper uses the annual data of West Texas Intermediate (WTI crude oil price in 1987–2014 as samples. We firstly present the direction and mechanism of the influence of oil price change on total consumption of every kind of energy by path analysis, and then consider establishing a Structural Vector Autoregression model of energy conservation and emission reduction in three statuses. Research shows that if the international oil price increases by 1%, the energy consumption per GDP and carbon dioxide emission increase by 0.092% and 0.053% respectively in the corresponding period. In the status of high energy consumption and high emission, if the international oil price increases by 1%, the energy consumption per GDP and carbon dioxide emission increase by 0.043% and 0.065% respectively in the corresponding period. In the status of low energy consumption and low emission, if the international oil price increases by 1%, the energy consumption per GDP per unit increases by 0.067% and carbon dioxide emission decreases by 0.085% in the corresponding period.

  7. Analysis of the international distribution of per capita CO2 emissions using the polarization concept

    International Nuclear Information System (INIS)

    Duro, Juan Antonio; Padilla, Emilio

    2008-01-01

    The concept of polarization is linked to the extent that a given distribution leads to the formation of homogeneous groups with opposing interests. This concept, which is basically different from the traditional one of inequality, is related to the level of inherent potential conflict in a distribution. The polarization approach has been widely applied in the analysis of income distribution. The extension of this approach to the analysis of international distribution of CO 2 emissions is quite useful as it gives a potent informative instrument for characterizing the state and evolution of the international distribution of emissions and its possible political consequences in terms of tensions and the probability of achieving agreements. In this paper we analyze the international distribution of per capita CO 2 emissions between 1971 and 2001 through the adaptation of the polarization concept and measures. We find that the most interesting grouped description deriving from the analysis is a two groups' one, which broadly coincide with Annex B and non-Annex B countries of the Kyoto Protocol, which shows the power of polarization analysis for explaining the generation of groups in the real world. The analysis also shows a significant reduction in international polarization in per capita CO 2 emissions between 1971 and 1995, but not much change since 1995, which might indicate that polarized distribution of emission is still one of the important factors leading to difficulties in achieving agreements for reducing global emissions. (author)

  8. Carbon emissions from international cruise ship passengers' travel to and from New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Howitt, Oliver J.A.; Revol, Vincent G.N.; Smith, Inga J.; Rodger, Craig J. [Department of Physics, University of Otago, PO Box 56, Dunedin (New Zealand)

    2010-05-15

    Greenhouse gas emissions from international transport contribute to anthropogenic global warming, yet these emissions are not liable under the Kyoto Protocol. International attention is being given to quantifying such emissions. This paper presents the results of research into international cruise ship journeys to and from New Zealand. CO{sub 2} emissions from such journeys were calculated using an activity based, or 'bottom-up', model. Emissions factors for individual journeys by cruise ships to or from New Zealand in 2007 ranged between 250 and 2200 g of CO{sub 2} per passenger-kilometre (g CO{sub 2} per p-km), with a weighted mean of 390 g CO{sub 2} per p-km. The weighted mean energy use per passenger night for the 'hotel' function of these cruise vessels was estimated as 1600 MJ per visitor night, 12 times larger than the value for a land-based hotel. Using a simple price elasticities calculation, international cruise journeys for transport purposes were found to have a greater relative decrease in demand than plane journeys when the impact of carbon pricing was analysed. The potential to decrease the CO{sub 2} emissions per p-km was examined, and if passenger accommodation was compacted and some luxury amenities dispensed with values similar to those of economy-class air travel were obtained. (author)

  9. Carbon emissions from international cruise ship passengers' travel to and from New Zealand

    International Nuclear Information System (INIS)

    Howitt, Oliver J.A.; Revol, Vincent G.N.; Smith, Inga J.; Rodger, Craig J.

    2010-01-01

    Greenhouse gas emissions from international transport contribute to anthropogenic global warming, yet these emissions are not liable under the Kyoto Protocol. International attention is being given to quantifying such emissions. This paper presents the results of research into international cruise ship journeys to and from New Zealand. CO 2 emissions from such journeys were calculated using an activity based, or 'bottom-up', model. Emissions factors for individual journeys by cruise ships to or from New Zealand in 2007 ranged between 250 and 2200 g of CO 2 per passenger-kilometre (g CO 2 per p-km), with a weighted mean of 390 g CO 2 per p-km. The weighted mean energy use per passenger night for the 'hotel' function of these cruise vessels was estimated as 1600 MJ per visitor night, 12 times larger than the value for a land-based hotel. Using a simple price elasticities calculation, international cruise journeys for transport purposes were found to have a greater relative decrease in demand than plane journeys when the impact of carbon pricing was analysed. The potential to decrease the CO 2 emissions per p-km was examined, and if passenger accommodation was compacted and some luxury amenities dispensed with values similar to those of economy-class air travel were obtained.

  10. Fast and Furious: Shock heated gas as the origin of spatially resolved hard X-ray emission in the central 5 kpc of the galaxy merger NGC 6240

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Junfeng; Nardini, Emanuele; Fabbiano, Giuseppina; Karovska, Margarita; Elvis, Martin; Risaliti, Guido; Zezas, Andreas [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Pellegrini, Silvia [Dipartimento di Astronomia, Universitá di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Max, Claire [Center for Adaptive Optics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); U, Vivian, E-mail: jfwang@northwestern.edu [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2014-01-20

    We have obtained a deep, subarcsecond resolution X-ray image of the nuclear region of the luminous galaxy merger NGC 6240 with Chandra, which resolves the X-ray emission from the pair of active nuclei and the diffuse hot gas in great detail. We detect extended hard X-ray emission from kT ∼ 6 keV (∼70 MK) hot gas over a spatial scale of 5 kpc, indicating the presence of fast shocks with a velocity of ∼2200 km s{sup –1}. For the first time, we obtain the spatial distribution of this highly ionized gas emitting Fe XXV, which shows a remarkable correspondence to the large-scale morphology of H{sub 2}(1-0) S(1) line emission and Hα filaments. Propagation of fast shocks originating in the starburst-driven wind into the ambient dense gas can account for this morphological correspondence. With an observed L {sub 0.5-8} {sub keV} = 5.3 × 10{sup 41} erg s{sup –1}, the diffuse hard X-ray emission is ∼100 times more luminous than that observed in the classic starburst galaxy M82. Assuming a filling factor of 1% for the 70 MK temperature gas, we estimate its total mass (M {sub hot} = 1.8 × 10{sup 8} M {sub ☉}) and thermal energy (E {sub th} = 6.5 × 10{sup 57} erg). The total iron mass in the highly ionized plasma is M {sub Fe} = 4.6 × 10{sup 5} M {sub ☉}. Both the energetics and the iron mass in the hot gas are consistent with the expected injection from the supernovae explosion during the starburst that is commensurate with its high star formation rate. No evidence for fluorescent Fe I emission is found in the CO filament connecting the two nuclei.

  11. Fast and Furious: Shock Heated Gas as the Origin of Spatially Resolved Hard X-Ray Emission in the Central 5 kpc of the Galaxy Merger NGC 6240

    Science.gov (United States)

    Wang, Junfeng; Nardini, Emanuele; Fabbiano, Giuseppina; Karovska, Margarita; Elvis, Martin; Pellegrini, Silvia; Max, Claire; Risaliti, Guido; U, Vivian; Zezas, Andreas

    2014-01-01

    We have obtained a deep, subarcsecond resolution X-ray image of the nuclear region of the luminous galaxy merger NGC 6240 with Chandra, which resolves the X-ray emission from the pair of active nuclei and the diffuse hot gas in great detail. We detect extended hard X-ray emission from kT ~ 6 keV (~70 MK) hot gas over a spatial scale of 5 kpc, indicating the presence of fast shocks with a velocity of ~2200 km s-1. For the first time, we obtain the spatial distribution of this highly ionized gas emitting Fe XXV, which shows a remarkable correspondence to the large-scale morphology of H2(1-0) S(1) line emission and Hα filaments. Propagation of fast shocks originating in the starburst-driven wind into the ambient dense gas can account for this morphological correspondence. With an observed L 0.5-8 keV = 5.3 × 1041 erg s-1, the diffuse hard X-ray emission is ~100 times more luminous than that observed in the classic starburst galaxy M82. Assuming a filling factor of 1% for the 70 MK temperature gas, we estimate its total mass (M hot = 1.8 × 108 M ⊙) and thermal energy (E th = 6.5 × 1057 erg). The total iron mass in the highly ionized plasma is M Fe = 4.6 × 105 M ⊙. Both the energetics and the iron mass in the hot gas are consistent with the expected injection from the supernovae explosion during the starburst that is commensurate with its high star formation rate. No evidence for fluorescent Fe I emission is found in the CO filament connecting the two nuclei.

  12. Fast and Furious: Shock heated gas as the origin of spatially resolved hard X-ray emission in the central 5 kpc of the galaxy merger NGC 6240

    International Nuclear Information System (INIS)

    Wang, Junfeng; Nardini, Emanuele; Fabbiano, Giuseppina; Karovska, Margarita; Elvis, Martin; Risaliti, Guido; Zezas, Andreas; Pellegrini, Silvia; Max, Claire; U, Vivian

    2014-01-01

    We have obtained a deep, subarcsecond resolution X-ray image of the nuclear region of the luminous galaxy merger NGC 6240 with Chandra, which resolves the X-ray emission from the pair of active nuclei and the diffuse hot gas in great detail. We detect extended hard X-ray emission from kT ∼ 6 keV (∼70 MK) hot gas over a spatial scale of 5 kpc, indicating the presence of fast shocks with a velocity of ∼2200 km s –1 . For the first time, we obtain the spatial distribution of this highly ionized gas emitting Fe XXV, which shows a remarkable correspondence to the large-scale morphology of H 2 (1-0) S(1) line emission and Hα filaments. Propagation of fast shocks originating in the starburst-driven wind into the ambient dense gas can account for this morphological correspondence. With an observed L 0.5-8 keV = 5.3 × 10 41 erg s –1 , the diffuse hard X-ray emission is ∼100 times more luminous than that observed in the classic starburst galaxy M82. Assuming a filling factor of 1% for the 70 MK temperature gas, we estimate its total mass (M hot = 1.8 × 10 8 M ☉ ) and thermal energy (E th = 6.5 × 10 57 erg). The total iron mass in the highly ionized plasma is M Fe = 4.6 × 10 5 M ☉ . Both the energetics and the iron mass in the hot gas are consistent with the expected injection from the supernovae explosion during the starburst that is commensurate with its high star formation rate. No evidence for fluorescent Fe I emission is found in the CO filament connecting the two nuclei.

  13. Greenhouse gas emissions from cities and regions: International implications revealed by Hong Kong

    International Nuclear Information System (INIS)

    Harris, Paul G.; Chow, Alice S.Y.; Symons, Jonathan

    2012-01-01

    The diversity of greenhouse gas (GHG) accounting methodologies currently utilized by cities around the world make meaningful comparisons of their emissions almost impossible. Consequently, the 2010 United Nations International Standard for Determining Greenhouse Gas Emissions for Cities promotes a “harmonized protocol for quantifying the GHG emissions attributable to cities and local regions.” The UN's common standard has important implications for comparison, benchmarking and policy assessment related to energy policies. This paper uses Hong Kong as a case study to illustrate these implications. Hong Kong's per capita contribution to GHG emissions are among the highest in the world, yet the local government's official statistics indicate emissions that are far below those reported by most affluent economies. This discrepancy arises from a reporting methodology that does not require inclusion of GHG emissions linked to consumption of imported goods or emissions from aviation and shipping. The Hong Kong case reveals that current inventories do not provide sufficient information to guide policymaking related to energy and climate change. They also do not provide adequate information for comparing policies of cities internationally. Alternative emissions-reporting standards that focus more on pollution from consumption will create avenues for more effective climate-related policies. - Highlights: ► Flawed GHG inventory methodologies can lead cities to adopt misguided policies. ► Diverse GHG inventory methodologies make meaningful comparisons among cities difficult. ► A Hong Kong case study highlights that GHG inventories can misrepresent cities' climate impacts. ► City inventories often exclude GHG emissions linked to imports, aviation and shipping. ► The International Standard for Determining GHG Emissions for Cities can assist climate policy.

  14. Trends in CO2 Emissions from China-Oriented International Marine Transportation Activities and Policy Implications

    Directory of Open Access Journals (Sweden)

    Hualong Yang

    2017-07-01

    Full Text Available The demand for marine transportation and its associated CO2 emissions are growing rapidly as a result of increasing international trade and economic growth. An activity-based approach is developed for forecasting CO2 emissions from the China-oriented international seaborne trade sector. To accurately estimate the aggregated emissions, CO2 emissions are calculated individually for five categories of vessels: crude oil tanker, product tanker, chemical tanker, bulk carrier, and container. A business-as-usual (BAU scenario was developed to describe the current situation without additional mitigation policies, whilst three alternative scenarios were developed to describe scenarios with various accelerated improvements of the key factors. The aggregated CO2 emissions are predicted to reach 419.97 Mt under the BAU scenario, and 258.47 Mt under the optimal case, AD3. These predictions are 4.5 times and 2.8 times that of the aggregated emissions in 2007. Our analysis suggests that regulations for monitoring, reporting, and verifying the activities of vessels should be proposed, in order to quantify the CO2 emissions of marine transportation activities in Chinese territorial waters. In the long-term future, mitigation policies should be employed to reduce CO2 emissions from the marine trade sector and to address the climatic impact of shipping.

  15. Modelling Energy Systems and International Trade in CO2 Emission Quotas - The Kyoto Protocol and Beyond

    International Nuclear Information System (INIS)

    Persson, Tobias A.

    2002-01-01

    A transformation of the energy system in the 21st century is required if the CO 2 concentration in the atmosphere should be stabilized at a level that would prevent dangerous anthropogenic interference with the climate system. The industrialized countries have emitted most of the anthropogenic CO 2 released to the atmosphere since the beginning of the industrial era and still account for roughly two thirds of global fossil fuel related CO 2 emissions. Industrial country CO 2 emissions on a per capita basis are roughly five to ten times higher than those of developing countries. However, a global atmospheric CO 2 concentration target of 450 ppm, if adopted would require that global average per capita CO 2 emissions by the end of this century have to be comparable to those of developing countries today. The industrialized countries would have to reduce their emissions substantially and the emissions in developing countries could not follow a business-as-usual scenario. The transformation of the energy system and abatement of CO 2 emissions would need to occur in industrialized and developing countries. Energy-economy models have been developed to analyze of international trading in CO 2 emission permits. The thesis consists of three papers. The cost of meeting the Kyoto Protocol is estimated in the first paper. The Kyoto Protocol, which defines quantitative greenhouse gas emission commitments for industrialized countries over the period 2008-2012, is the first international agreement setting quantitative goals for abatement of CO 2 emissions from energy systems. The Protocol allows the creation of systems for trade in emission permits whereby countries exceeding their target levels can remain in compliance by purchasing surplus permits from other developed countries. However, a huge carbon surplus, which has been christened hot air, has been created in Russia and Ukraine since 1990 primarily because of the contraction of their economies. The current Unites States

  16. Emissions trading in the real world : Ontario Power Generation's domestic and international trading activities

    International Nuclear Information System (INIS)

    Jantzi, B.

    2001-01-01

    In this presentation, the author discussed Ontario Power Generation's voluntary commitment to stabilize carbon dioxide equivalent emissions at 1990 levels. To do so, Ontario Power Generation is implementing a series of green energy initiatives, a corporate tree planting program, internal energy efficiency, and an emission reduction trading (ERT). The emphasis was placed on emission trading, where Ontario Power Generation is a leader in the field of greenhouse gas, nitrogen oxide and sulphur dioxide trading in Canada. The approach to trading adopted was explained, with the specifics provided for each of the different categories of emissions. Some examples further illustrated the process. The outlook for the future was outlined, with plans for the geological sequestration of carbon dioxide and enhanced oil recovery, low nitrogen oxide gasoline additive. The benefits of emission trading were discussed from the perspective of Ontario Power Generation and the environment, such as allowing real reductions in emissions in a cost effective manner, enhanced risk management, investments in emissions reductions. The author argued that emission reduction is the way of the future, representing the only way in which the greenhouse gas emissions reductions required to minimize global climate change will be accomplished

  17. Analysis and Design of International Emission Trading Markets Applying System Dynamics Techniques

    Science.gov (United States)

    Hu, Bo; Pickl, Stefan

    2010-11-01

    The design and analysis of international emission trading markets is an important actual challenge. Time-discrete models are needed to understand and optimize these procedures. We give an introduction into this scientific area and present actual modeling approaches. Furthermore, we develop a model which is embedded in a holistic problem solution. Measures for energy efficiency are characterized. The economic time-discrete "cap-and-trade" mechanism is influenced by various underlying anticipatory effects. With a systematic dynamic approach the effects can be examined. First numerical results show that fair international emissions trading can only be conducted with the use of protective export duties. Furthermore a comparatively high price which evokes emission reduction inevitably has an inhibiting effect on economic growth according to our model. As it always has been expected it is not without difficulty to find a balance between economic growth and emission reduction. It can be anticipated using our System Dynamics model simulation that substantial changes must be taken place before international emissions trading markets can contribute to global GHG emissions mitigation.

  18. Low-velocity Shocks Traced by Extended SiO Emission along the W43 Ridges: Witnessing the Formation of Young Massive Clusters

    Science.gov (United States)

    Nguyen-Lu'o'ng, Q.; Motte, F.; Carlhoff, P.; Louvet, F.; Lesaffre, P.; Schilke, P.; Hill, T.; Hennemann, M.; Gusdorf, A.; Didelon, P.; Schneider, N.; Bontemps, S.; Duarte-Cabral, A.; Menten, K. M.; Martin, P. G.; Wyrowski, F.; Bendo, G.; Roussel, H.; Bernard, J.-P.; Bronfman, L.; Henning, T.; Kramer, C.; Heitsch, F.

    2013-10-01

    The formation of high-mass stars is tightly linked to that of their parental clouds. Here, we focus on the high-density parts of W43, a molecular cloud undergoing an efficient event of star formation. Using a column density image derived from Herschel continuum maps, we identify two high-density filamentary clouds, called the W43-MM1 and W43-MM2 ridges. Both have gas masses of 2.1 × 104 M ⊙ and 3.5 × 104 M ⊙ above >10^{23}\\, {{cm}^{-2}} and within areas of ~6 and ~14 pc2, respectively. The W43-MM1 and W43-MM2 ridges are structures that are coherent in velocity and gravitationally bound, despite their large velocity dispersion measured by the N2H+ (1-0) lines of the W43-HERO IRAM large program. Another intriguing result is that these ridges harbor widespread (~10 pc2) bright SiO (2-1) emission, which we interpret to be the result of low-velocity shocks (models to demonstrate that a small percentage (10%) of Si atoms in low-velocity shocks, observed initially in gas phase or in grain mantles, can explain the observed SiO column density in the W43 ridges. The spatial and velocity overlaps between the ridges of high-density gas and the shocked SiO gas suggest that ridges could be forming via colliding flows driven by gravity and accompanied by low-velocity shocks. This mechanism may be the initial conditions for the formation of young massive clusters.

  19. Concept for lowest emissions of a hydrogen internal combustion engine; Niedrigstemissionskonzept fuer einen wasserstoffbetriebenen Verbrennungsmotor

    Energy Technology Data Exchange (ETDEWEB)

    Fouquet, Marcel Christian Thomas

    2012-03-15

    This paper describes a concept with lowest emissions for a hydrogen internal combustion engine for passenger cars. With optimisation of the combustion concept the level of nitrogen oxide is below 90%, hydrocarbon and carbon monoxide below 99% of the SULEV target (CARB). This concept enables a potential in power density that is comparable to current supercharged combustion engines at lowest emission level without catalytic aftertreatment. Additionally with a catalytic aftertreatment system, the emission level of a current hydrogen combustion engine (mono-fuel) is lowered to a level, that this car can be labeled as air cleaning vehicle for hydrocarbons and carbon monoxide.

  20. Internal combustion engine run on biogas is a potential solution to meet Indonesia emission target

    Science.gov (United States)

    Ambarita, Himsar

    2017-09-01

    Indonesia has released two different Greenhouse Gas (GHG) emissions reduction targets. The first target, released in 2009, is reduction GHG emissions 26% from Business-as-Usual (BAU) level using own budget and up 41% if supported international aids by 2020. The second target is reduction 29% and 41% from BAU by 2030 using own budget and with international support, respectively. In this paper, the BAU emissions and emissions reduction target of these two targets are elaborated. In addition, the characteristics of emissions from transportation sector are discussed. One of the potential mitigation actions is switching fuel in transportation sector. The results the most promising mitigation action in the transportation is switching oil fuel with biofuel. The Government of Indonesia (GoI) focuses on using biodiesel and bioethanol to run internal combustion engine in transportation sector and biogas is aimed to fuel power plant unit. However, there is very limited of success stories on using biogas in the power plant. The barriers and challenges will be discussed here. It is suggested to run internal combustion engine with biogas.

  1. Attribution of CO2 emissions from Brazilian deforestation to domestic and international drivers

    Science.gov (United States)

    Karstensen, J.; Peters, G.

    2011-12-01

    Efforts to address extensive deforestation to reduce climate change and save primary forests are taking place on a global scale. Whilst several studies have estimated the emissions occurring from deforestation in large rainforests, few studies have investigated the domestic and international drivers sustaining and increasing the deforestation rates. Brazil, having the largest rainforest in the world and one of the highest deforestation rates, is also currently one of the world's largest exporters of soybeans and beef. In this case study we establish the link between Brazilian deforestation and cattle and soybean production, and further attribute emissions to countries and economic sectors through export and import of Brazilian commodities. The emissions from deforestation can therefore be allocated to the countries and sectors consuming goods and services produced on deforested land in Brazil. A land-use change model and deforestation data is coupled with a carbon cycle model to create yearly emission estimates and different emission allocation schemes, depending on emission amortizations and discounting functions for past deforestation. We use an economic multi-regional input-output model (with 112 regions and 57 sectors) to distribute these emissions along agricultural trade routes, through domestic and international consumption in 2004. With our implementation we find that around 80 % of emissions from deforested land is due to cattle grazing, while agricultural transition effects suggests soy beans are responsible for about 20 % of the emissions occurring in 2004. Nearly tree quarters of the soy beans are consumed outside Brazil, of which China, Germany and France are the biggest consumers. Soy beans are consumed by a variety of sectors in the food industry. Brazil exports about 30 % of the cattle it produces, where Russia, USA and Germany are among the largest consumers. Cattle consumption mainly occurs in the meat sectors. In this study we estimate the CO2

  2. Cavitation and shock waves emission on the rigid boundary of water under mid-IR nanosecond laser pulse excitation

    Science.gov (United States)

    Pushkin, A. V.; Bychkov, A. S.; Karabutov, A. A.; Potemkin, F. V.

    2018-06-01

    The processes of conversion of light energy into mechanical energy under mid-IR nanosecond laser excitation on a rigid boundary of water are investigated. Strong water absorption of Q-switched Cr:Yb:Ho:YSGG (2.85 µm, 6 mJ, 45 ns) laser radiation provides rapid energy deposition of ~8 kJ cm‑3 accompanied with strong mechanical transients. The evolution of shock waves and cavitation bubbles is studied using the technique of shadowgraphy and acoustic measurements, and the conversion efficiency into these energy channels for various laser fluence (0.75–2.0 J cm‑2) is calculated. For 6 mJ laser pulse with fluence of 2.0 J cm‑2, the conversion into shock wave energy reaches 67%. The major part of the shock wave energy (92%) is dissipated when the shock front travels the first 250 µm, and the remaining 8% is transferred to the acoustic far field. The calculated pressure in the vicinity of water-silicon interface is 0.9 GPa. Cavitation efficiency is significantly less and reaches up to 5% of the light energy. The results of the current study could be used in laser parameters optimization for micromachining and biological tissue ablation.

  3. Internalizing carbon costs in electricity markets: Using certificates in a load-based emissions trading scheme

    International Nuclear Information System (INIS)

    Gillenwater, Michael; Breidenich, Clare

    2009-01-01

    Several western states have considered developing a regulatory approach to reduce greenhouse gas (GHG) emissions from the electric power industry, referred to as a load-based (LB) cap-and-trade scheme. A LB approach differs from the traditional source-based (SB) cap-and-trade approach in that the emission reduction obligation is placed upon Load Serving Entities (LSEs), rather than electric generators. The LB approach can potentially reduce the problem of emissions leakage, relative to a SB system. For any of these proposed LB schemes to be effective, they must be compatible with modern, and increasingly competitive, wholesale electricity markets. LSE's are unlikely to know the emissions associated with their power purchases. Therefore, a key challenge for a LB scheme is how to assign emissions to each LSE. This paper discusses the problems with one model for assigning emissions under a LB scheme and proposes an alternative, using unbundled Generation Emission Attribute Certificates. By providing a mechanism to internalize an emissions price signal at the generator dispatch level, the tradable certificate model addresses both these problems and provides incentives identical to a SB scheme

  4. Marine energy consumption, national economic activity, and greenhouse gas emissions from international shipping

    International Nuclear Information System (INIS)

    Chang, Ching-Chih

    2012-01-01

    The causal relationships among marine energy consumption, greenhouse gas emissions from international shipping, and economic growth for Kyoto Protocol Annex I countries for the period of 1990 to 2006 are discussed. The real gross domestic product is used as a proxy for economic activity. The United States is also discussed because it was the main global polluter before 2006. The co-integration methodology and an error-correction model are used to examine the causal relationships. The empirical results show that marine energy consumption and GDP are the main factors of increased GHG emissions in the short-run, and that economic activity significantly increased emissions in the long-run. Emissions from shipping are more closely related to marine energy consumption than to economic activity. Hence, policies for mitigating greenhouse gas emissions from marine shipping need to focus on greater energy efficiency in the design of ship engines and hulls. - Highlights: ► Energy consumption and GDP are the main causes to increased GHG emissions in the shipping industry. ► Emissions from shipping are more closely related to energy consumption than to GDP. ► Policies to mitigate GHG emissions from shipping industry should focus on the engine and hull design.

  5. Regulated and unregulated emissions from an internal combustion engine operating on ethanol-containing fuels

    Science.gov (United States)

    Poulopoulos, S. G.; Samaras, D. P.; Philippopoulos, C. J.

    In the present work, the effect of ethanol addition to gasoline on regulated and unregulated emissions is studied. A 4-cylinder OPEL 1.6 L internal combustion engine equipped with a hydraulic brake dynamometer was used in all the experiments. For exhaust emissions treatment a typical three-way catalyst was used. Among the various compounds detected in exhaust emissions, the following ones were monitored at engine and catalyst outlet: methane, hexane, ethylene, acetaldehyde, acetone, benzene, 1,3-butadiene, toluene, acetic acid and ethanol. Addition of ethanol in the fuel up to 10% w/w had as a result an increase in the Reid vapour pressure of the fuel, which indicates indirectly increased evaporative emissions, while carbon monoxide tailpipe emissions were decreased. For ethanol-containing fuels, acetaldehyde emissions were appreciably increased (up to 100%), especially for fuel containing 3% w/w ethanol. In contrast, aromatics emissions were decreased by ethanol addition to gasoline. Methane and ethanol were the most resistant compounds to oxidation while ethylene was the most degradable compound over the catalyst. Ethylene, methane and acetaldehyde were the main compounds present at engine exhaust while methane, acetaldehyde and ethanol were the main compounds in tailpipe emissions for ethanol fuels after the catalyst operation.

  6. Study of carbon dioxide emission inventory from transportation sector at Kualanamu International Airport

    Science.gov (United States)

    Suryati, I.; Indrawan, I.; Alihta, K. N.

    2018-02-01

    Transportation includes sources of greenhouse gas emission contributor in the form of carbon dioxide (CO2). CO2 is one of the air pollutant gases that cause climate change. The source of CO2 emissions at airports comes from road and air transportation. Kualanamu International Airport is one of the public service airports in North Sumatera Province. The purpose of this study is to inventory the emission loads generated by motor vehicles and aircraft and to forecast contributions of CO2 emissions from motor vehicles and aircraft. The research method used is quantitative and qualitative methods. The quantitative method used is to estimate emission loads of motor vehicles based on vehicle volume and emission factors derived from the literature and using the Tier-2 method to calculate the aircraft emission loads. The results for the maximum CO2 concentration were 6,206,789.37 μg/m3 and the minimal CO2 concentration was 4,070,674.84 μg/Nm3. The highest aircraft CO2 emission load is 200,164,424.5 kg/hr (1.75 x 109 ton/year) and the lowest is 38,884,064.5 kg/hr (3.40 x 108 ton/year). Meanwhile, the highest CO2 emission load from motor vehicles was 51,299.25 gr/hr (449,38 ton/year) and the lowest was 38,990.42 gr/hr (341,55 ton/year). CO2 contribution from a motor vehicle is 65% and 5% from aircraft in Kualanamu International Airport.

  7. Circulatory Shock. Volume 34. Number 1. May 1991. International Conference on Shock (2nd), Meeting of European Shock Society (5th), Annual Meeting of the Shock Society (USA) (14th), Vienna Shock Form (3rd) Held in Vienna, Austria on 2-6 June 1991

    Science.gov (United States)

    1991-06-06

    OCTADECENOATE, AS A BURN TOXIN Takayuki Ozawa, Mika Hayakawa, Kazuhiro Kosaka, Satoru Sugiyama, Kazuhisa Yokoo, Hisashi Aoyama, and Yohei Izawa Department...shock. 41 CARDIOPULMONARY HEMODYNAMIC AND PERIPHERAL CIRCULATORY RESPONSES IN SHOCK T. Muteki, N. Kaku. T. Fukushige, I. Kohno and T. Hiraki Department...Tadashi, 242 Machleidt, Werner, 213 Ozawa, Takayuki , 11 Kawarada, Yoshifumi, 442 Mackie, D.P., 348 Ozawa, Kazue, 268 Keser, Claudia, 380 Maitra, Subir R

  8. Emission trading and Kyoto's protocol: discussions concerning rules and international coordination

    International Nuclear Information System (INIS)

    Baron, R.

    2000-01-01

    The Kyoto Protocol of the Climate Convention introduced the possibility to trade greenhouse gas emission reductions among industrialized countries, as a means to reduce the total cost of achieving the agreed emission goals. The rules for this international co-ordination regime are still debated, even if its principle is generally agreed. This article, written before the negotiation in the Hague, summarizes how the notion of emission trading made its way in the Framework Convention on Climate Change. The authors show what economic gains could realistically be expected from emission trading, based on macro-economic modelling results and a simulation of trading in the conditions of the Kyoto Protocol. They stress the critical contribution that emission trading could make, provided that the Protocol's environmental basis is not undermined. In the end, the negotiation collapsed over this issue. Beyond this near-term obstacle, the international emission trading system represents a significant progress towards an efficient resolution of man-made global climate change. (author)

  9. Carbon dioxide emissions embodied in international trade in Central Europe between 1995 and 2008

    Directory of Open Access Journals (Sweden)

    Vlčková Jana

    2015-12-01

    Full Text Available Climate change and environmental policies are widely discussed, but much less is known about emissions embodied in goods traded internationally, and the distinction between emission producers and consumers. The carbon dioxide emissions embodied in international trade in Central European countries are subject to examination in this paper. As a result of industrial restructuring and environmental legislation, air pollution has improved significantly in Central European countries since the 1989 transition. On the other hand, economic growth has been accompanied by a rise in consumerism. Despite the increasing role of exports, the Visegrad group countries have become net importers of carbon dioxide emissions between 1995 and 2008. This seems to be the ‘standard trajectory’ of a country’s transition toward a more developed and consumption-oriented economy. The global patterns of carbon dioxide emissions embodied in manufacturing exports are also mapped, using network analysis and constructing ‘product space’. The analysis confirms that industrial re-structuring played an important role in lowering the production of carbon dioxide emissions in the Visegrad countries.

  10. Jet formation and shock wave emission during collapse of ultrasound-induced cavitation bubbles and their role in the therapeutic applications of high-intensity focused ultrasound.

    Science.gov (United States)

    Brujan, E A; Ikeda, T; Matsumoto, Y

    2005-10-21

    The dynamics of inertial cavitation bubbles produced by short pulses of high-intensity focused ultrasound near a rigid boundary are studied to get a better understanding of the role of jet formation and shock wave emission during bubble collapse in the therapeutic applications of ultrasound. The bubble dynamics are investigated by high-speed photography with up to 2 million frames/s and acoustic measurements, as well as by numerical calculations. The significant parameter of this study is the dimensionless stand-off, gamma, which is defined as the distance of the bubble centre at its maximum expansion scaled by the maximum bubble radius. High-speed photography is applied to observe the bubble motion and the velocity of the liquid jet formed during bubble collapse. Hydrophone measurements are used to determine the pressure and the duration of the shock wave emitted during bubble rebound. Calculations yield the variation with time of the bubble wall, the maximum velocity and the kinetic energy of the re-entrant jet. The comparisons between experimental and numerical data are favourable with regard to both shape history and translational motion of the bubble. The acoustic energy constitutes the largest individual amount in the energy balance of bubble collapse. The ratio of the shock wave energy, measured at 10 mm from the emission centre, to the cavitation bubble energy was 1:2.4 at gamma = 1.55 and 1:3.5 at gamma = 1. At this distance, the shock wave pressure ranges from 0.122 MPa, at gamma = 1, to 0.162 MPa, at gamma = 1.55, and the temporal duration at the half maximum level is 87 ns. The maximum jet velocity ranges from 27 m s(-1), at gamma = 1, to 36 m s(-1), at gamma = 1.55. For gamma < 1.2, the re-entrant jet can generate an impact pressure on the nearby boundary larger than 50 MPa. We discuss the implications of the results for the therapeutic applications of high-intensity focused ultrasound.

  11. Jet formation and shock wave emission during collapse of ultrasound-induced cavitation bubbles and their role in the therapeutic applications of high-intensity focused ultrasound

    International Nuclear Information System (INIS)

    Brujan, E A; Ikeda, T; Matsumoto, Y

    2005-01-01

    The dynamics of inertial cavitation bubbles produced by short pulses of high-intensity focused ultrasound near a rigid boundary are studied to get a better understanding of the role of jet formation and shock wave emission during bubble collapse in the therapeutic applications of ultrasound. The bubble dynamics are investigated by high-speed photography with up to 2 million frames/s and acoustic measurements, as well as by numerical calculations. The significant parameter of this study is the dimensionless stand-off, γ, which is defined as the distance of the bubble centre at its maximum expansion scaled by the maximum bubble radius. High-speed photography is applied to observe the bubble motion and the velocity of the liquid jet formed during bubble collapse. Hydrophone measurements are used to determine the pressure and the duration of the shock wave emitted during bubble rebound. Calculations yield the variation with time of the bubble wall, the maximum velocity and the kinetic energy of the re-entrant jet. The comparisons between experimental and numerical data are favourable with regard to both shape history and translational motion of the bubble. The acoustic energy constitutes the largest individual amount in the energy balance of bubble collapse. The ratio of the shock wave energy, measured at 10 mm from the emission centre, to the cavitation bubble energy was 1:2.4 at γ = 1.55 and 1:3.5 at γ = 1. At this distance, the shock wave pressure ranges from 0.122 MPa, at γ = 1, to 0.162 MPa, at γ 1.55, and the temporal duration at the half maximum level is 87 ns. The maximum jet velocity ranges from 27 m s -1 , at γ = 1, to 36 m s -1 , at γ = 1.55. For γ < 1.2, the re-entrant jet can generate an impact pressure on the nearby boundary larger than 50 MPa. We discuss the implications of the results for the therapeutic applications of high-intensity focused ultrasound

  12. Notification: Evaluating the Internal Controls for EPA's Vehicle Emissions Testing Program

    Science.gov (United States)

    Project #OPE-FY17-0009, Mar 6, 2017. The EPA OIG plans to begin preliminary research to determine whether the EPA’s existing internal controls are effective at detecting and preventing light-, medium-, and heavy-duty on-road vehicle emissions fraud.

  13. 14th International Conference on Particle Induced X-ray Emission ("PIXE 2015")

    Science.gov (United States)

    Przybyłowicz, Wojciech Józef; Pineda-Vargas, Carlos

    2015-11-01

    This special issue of Nuclear Instruments and Methods in Physics Research B contains the proceedings of the 14th International Conference on Particle Induced X-ray Emission ("PIXE 2015") that was held in Somerset West (South Africa) from 25th February to 3rd March 2015.

  14. The design and implementation of an international trading scheme for greenhouse gas emissions

    NARCIS (Netherlands)

    Zhang, ZX

    The inclusion of emissions trading in the Kyoto Protocol reflects an important decision to address climate-change issues through flexible market mechanisms. The author addresses a number of policy issues that must be considered in designing and implementing an international greenhouse gas (GHG)

  15. 75 FR 80761 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-12-23

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 63 [EPA-HQ-OAR-2008-0708, FRL-9244-2] RIN 2060-AP36 National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... combustion engines and requesting public comment on one issue arising from the final rule. Specifically, EPA...

  16. Potential biodiversity benefits from international programs to reduce carbon emissions from deforestation.

    Science.gov (United States)

    Siikamäki, Juha; Newbold, Stephen C

    2012-01-01

    Deforestation is the second largest anthropogenic source of carbon dioxide emissions and options for its reduction are integral to climate policy. In addition to providing potentially low cost and near-term options for reducing global carbon emissions, reducing deforestation also could support biodiversity conservation. However, current understanding of the potential benefits to biodiversity from forest carbon offset programs is limited. We compile spatial data on global forest carbon, biodiversity, deforestation rates, and the opportunity cost of land to examine biodiversity conservation benefits from an international program to reduce carbon emissions from deforestation. Our results indicate limited geographic overlap between the least-cost areas for retaining forest carbon and protecting biodiversity. Therefore, carbon-focused policies will likely generate substantially lower benefits to biodiversity than a more biodiversity-focused policy could achieve. These results highlight the need to systematically consider co-benefits, such as biodiversity in the design and implementation of forest conservation programs to support international climate policy.

  17. Tracking the CME-driven shock wave on 2012 march 5 and radio triangulation of associated radio emission

    Czech Academy of Sciences Publication Activity Database

    Magdalenic, J.; Marqué, C.; Krupař, Vratislav; Mierla, M.; Zhukov, A. N.; Rodriguez, L.; Maksimovic, M.; Cecconi, B.

    2014-01-01

    Roč. 791, č. 2 (2014), s. 1-14 ISSN 0004-637X R&D Projects: GA ČR GAP205/10/2279 Institutional support: RVO:68378289 Keywords : coronal mass ejections (CMEs) * shock waves * Sun: corona * Sun: flares * Sun: radio radiation Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 5.993, year: 2014 http://iopscience.iop.org/0004-637X/791/2/115

  18. Emission trading and international competition: The impact of labor market rigidity on technology adoption and output

    International Nuclear Information System (INIS)

    Caparrós, Alejandro; Péreau, Jean-Christophe; Tazdaït, Tarik

    2013-01-01

    Emission trading systems have been proposed in different regions to reduce polluting emissions and are in use in the European Union for carbon dioxide emissions. One of the objectives of these systems is to encourage firms to adopt advanced abatement technologies. However, permits also create an incentive to reduce output, which may be seen as negative by policy makers. We analyze the impact of a rigid labour market on these two outcomes, showing the conditions necessary to avoid reductions in production while keeping the incentives to improve abatement technologies. The analysis is done for oligopolistic firms engaged in international rivalry. - Highlights: ► Emission trading reduces production and improves abatement technologies. ► Policy makers see the first outcome as negative and the second as positive. ► This paper studies the impact of market rigidity on these two outcomes. ► It shows conditions to avoid the first outcome and maintain or enhance the second

  19. Nitrogen enriched combustion of a natural gas internal combustion engine to reduce NO.sub.x emissions

    Science.gov (United States)

    Biruduganti, Munidhar S.; Gupta, Sreenath Borra; Sekar, R. Raj; McConnell, Steven S.

    2008-11-25

    A method and system for reducing nitrous oxide emissions from an internal combustion engine. An input gas stream of natural gas includes a nitrogen gas enrichment which reduces nitrous oxide emissions. In addition ignition timing for gas combustion is advanced to improve FCE while maintaining lower nitrous oxide emissions.

  20. Carbon dioxide emission and economic growth of China-the role of international trade.

    Science.gov (United States)

    Boamah, Kofi Baah; Du, Jianguo; Bediako, Isaac Asare; Boamah, Angela Jacinta; Abdul-Rasheed, Alhassan Alolo; Owusu, Samuel Mensah

    2017-05-01

    This study investigates the role of international trade in mitigating carbon dioxide emission as a nation economically advances. This study disaggregated the international trade into total exports and total imports. A multivariate model framework was estimated for the time series data for the period of 1970-2014. The quantile regression detected all the essential relationship, which hitherto, the traditional ordinary least squares could not capture. A cointegration relationship was confirmed using the Johansen cointegration model. The findings of the Granger causality revealed the presence of a uni-directional Granger causality running from energy consumption to economic growth; from import to economic growth; from imports to exports; and from urbanisation to economic growth, exports and imports. Our study established the presence of long-run relationships amongst carbon dioxide emission, economic growth, energy consumption, imports, exports and urbanisation. A bootstrap method was further utilised to reassess the evidence of the Granger causality, of which the results affirmed the Granger causality in the long run. This study confirmed a long-run N-shaped relationship between economic growth and carbon emission, under the estimated cubic environmental Kuznet curve framework, from the perspective of China. The recommendation therefore is that China as export leader should transform its trade growth mode by reducing the level of carbon dioxide emission and strengthening its international cooperation as it embraces more environmental protectionisms.

  1. Unified model of plasma formation, bubble generation and shock wave emission in water for fs to ns laser pulses (Conference Presentation)

    Science.gov (United States)

    Liang, Xiao-Xuan; Freidank, Sebastian; Linz, Norbert; Paltauf, Günther; Zhang, Zhenxi; Vogel, Alfred

    2017-03-01

    We developed modeling tools for optical breakdown events in water that span various phases reaching from breakdown initiation via solvated electron generation, through laser induced-plasma formation and temperature evolution in the focal spot to the later phases of cavitation bubble dynamics and shock wave emission and applied them to a large parameter space of pulse durations, wavelengths, and pulse energies. The rate equation model considers the interplay of linear absorption, photoionization, avalanche ionization and recombination, traces thermalization and temperature evolution during the laser pulse, and portrays the role of thermal ionization that becomes relevant for T > 3000 K. Modeling of free-electron generation includes recent insights on breakdown initiation in water via multiphoton excitation of valence band electrons into a solvated state at Eini = 6.6 eV followed by up-conversion into the conduction band level that is located at 9.5 eV. The ability of tracing the temperature evolution enabled us to link the model of laser-induced plasma formation with a hydrodynamic model of plasma-induced pressure evolution and phase transitions that, in turn, traces bubble generation and dynamics as well as shock wave emission. This way, the amount of nonlinear energy deposition in transparent dielectrics and the resulting material modifications can be assessed as a function of incident laser energy. The unified model of plasma formation and bubble dynamics yields an excellent agreement with experimental results over the entire range of investigated pulse durations (femtosecond to nanosecond), wavelengths (UV to IR) and pulse energies.

  2. Emission characterization and evaluation of natural gas-fueled cogeneration microturbines and internal combustion engines

    International Nuclear Information System (INIS)

    Canova, Aldo; Chicco, Gianfranco; Genon, Giuseppe; Mancarella, Pierluigi

    2008-01-01

    The increasing diffusion of small-scale energy systems within the distributed generation (DG) paradigm is raising the need for studying the environmental impact due to the different DG solutions in order to assess their sustainability. Addressing the environmental impact calls for building specific models for studying both local and global emissions. In this framework, the adoption of natural gas-fueled DG cogeneration technologies may provide, as a consequence of cogeneration enhanced overall energy efficiency and of natural gas relatively low carbon content, a significant reduction of global impact in terms of CO 2 emissions with respect to the separate production of electricity and heat. However, a comprehensive evaluation of the DG alternatives should take into account as well the impact due to the presence of plants spread over the territory that could increase the local pollution, in particular due to CO and NO x , and thus could worsen the local air quality. This paper provides an overview on the characterization of the emissions from small-scale natural gas-fueled cogeneration systems, with specific reference to the DG technologies nowadays most available in the market, namely, microturbines and internal combustion engines. The corresponding local and global environmental impacts are evaluated by using the emission balance approach. A numerical case study with two representative machines highlights their different emission characteristics, also considering the partial-load emission performance

  3. Terminal-shock and restart control of a Mach 2.5, axisymmetric, mixed compression inlet with 40 percent internal contraction. [wind tunnel tests

    Science.gov (United States)

    Baumbick, R. J.

    1974-01-01

    Results of experimental tests conducted on a supersonic, mixed-compression, axisymmetric inlet are presented. The inlet is designed for operation at Mach 2.5 with a turbofan engine (TF-30). The inlet was coupled to either a choked orifice plate or a long duct which had a variable-area choked exit plug. Closed-loop frequency responses of selected diffuser static pressures used in the terminal-shock control system are presented. Results are shown for Mach 2.5 conditions with the inlet coupled to either the choked orifice plate or the long duct. Inlet unstart-restart traces are also presented. High-response inlet bypass doors were used to generate an internal disturbance and also to achieve terminal-shock control.

  4. A study on the evaluation of internal leak in valve using acoustic emission method(3)

    International Nuclear Information System (INIS)

    Lee, Sang Guk; Lee, Wook Ryun; Park, Jong Hyuck; Kim, Kwang Hong

    2005-01-01

    The objective of this study is to estimate the feasibility of acoustic emission method for the internal leak from the valves. In this study, valve leak tests using various types of specimen simulated seat damage were performed in order to analyzer acoustic emission properties when leaks arise in valve seat. As a result of leak test for specimens simulated valve seat, we conformed that leak sound level increased in proportion to the increase of hole diameter and leak velocity, and decreased in proportion to the increase of leak depth. And also, leak sound level has hysteresis for leak velocity. From the experimental results, it was suggested that the acoustic emission method for monitoring of leak was feasible.

  5. International trade in oil, gas and carbon emission rights: An intertemporal general equilibrium model

    International Nuclear Information System (INIS)

    Manne, A.S.; Rutherford, T.F.

    1994-01-01

    This paper employs a five-region intertemporal model to examine three issues related to carbon emission restrictions. First, we investigate the possible impact of such limits upon future oil prices. We show that carbon limits are likely to differ in their near- and long-term impact. Second, we analyze the problem of open-quotes leakageclose quotes which could arise if the OECD countries were to adopt unilateral limits upon carbon emissions. Third, we quantify some of the gains from trade in carbon emission rights. Each of these issues have been studied before, but to our knowledge this is the first study based on a multi-regional, forward-looking model. We show that sequential joint maximization can be an effective way to compute equilibria for intertemporal general equilibrium models of international trade. 18 refs., 10 figs

  6. International Assistance for Low-Emission Development Planning: Coordinated Low Emissions Assistance Network (CLEAN) Inventory of Activities and Tools--Preliminary Trends

    Energy Technology Data Exchange (ETDEWEB)

    Cox, S.; Benioff, R.

    2011-05-01

    The Coordinated Low Emissions Assistance Network (CLEAN) is a voluntary network of international practitioners supporting low-emission planning in developing countries. The network seeks to improve quality of support through sharing project information, tools, best practices and lessons, and by fostering harmonized assistance. CLEAN has developed an inventory to track and analyze international technical support and tools for low-carbon planning activities in developing countries. This paper presents a preliminary analysis of the inventory to help identify trends in assistance activities and tools available to support developing countries with low-emission planning.

  7. Signalling in international environmental agreements. Using pre-agreement emission level as a signalling device

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, U.

    1997-12-31

    This paper addresses the question about strategic incentives in international environmental agreements and tries to give a positive description of how the design of the agreement influences the strategic behaviour of potential participants before they enter the treaty. A common feature of the design of agreements is that the reduction obligations (RO) are made contingent on a pre-agreement or baseline emission. As it is assumed that countries posses better information about their reduction costs than does the international body in charge of deciding the RO, countries might have incentives to signal higher costs by increasing their baseline emission, and thereby reducing the costs of entering the agreement. The appropriate analytical framework is to use a signalling game approach, where the pre-agreement emission level conveys information about the privately informed country`s reduction cost. In this paper two types of agreement design are considered, one with uniform obligations, and one with differentiated obligations. This enables us to make a comparison between two different reduction regimes. The result is that the predicted outcomes vary with regard to both the environmental effectiveness and the associated expected costs for the participating countries. This means that when private information is considered, the anticipation of a given institutional framework has significant impact on the resulting distortion of the total emission level, highlighting the necessity of taking this into consideration when future designs are proposed. (au)

  8. Signalling in international environmental agreements: Using pre-agreement emission level as a signalling device

    International Nuclear Information System (INIS)

    Steiner, U.

    1997-01-01

    This paper addresses the question about strategic incentives in international environmental agreements and tries to give a positive description of how the design of the agreement influences the strategic behaviour of potential participants before they enter the treaty. A common feature of the design of agreements is that the reduction obligations (RO) are made contingent on a pre-agreement or baseline emission. As it is assumed that countries posses better information about their reduction costs than does the international body in charge of deciding the RO, countries might have incentives to signal higher costs by increasing their baseline emission, and thereby reducing the costs of entering the agreement. The appropriate analytical framework is to use a signalling game approach, where the pre-agreement emission level conveys information about the privately informed country's reduction cost. In this paper two types of agreement design are considered, one with uniform obligations, and one with differentiated obligations. This enables us to make a comparison between two different reduction regimes. The result is that the predicted outcomes vary with regard to both the environmental effectiveness and the associated expected costs for the participating countries. This means that when private information is considered, the anticipation of a given institutional framework has significant impact on the resulting distortion of the total emission level, highlighting the necessity of taking this into consideration when future designs are proposed. (au)

  9. The effect of oil additives on exhaust emission of internal combustion engines

    International Nuclear Information System (INIS)

    Dimitrovski, M.B.; Kuzmanovski, K.A.

    1999-01-01

    An attempt was conducted to acquire data on connection between motor oil and motor oil additives and exhaust emission of internal combustion engine. The consulted literature did not contain enough data, so experiments were conducted. The results of the experiments are presented on diagrams that have been processed in the computer program EXCEL. Conclusions that were made out of that work show the need of expanding research on the subject. (Author)

  10. Final report on the reactor pressure vessel pressurized-thermal-shock. International comparative assessment study (RPV PTS ICAS)

    International Nuclear Information System (INIS)

    Sievers, J.; Schulz, H.; Bass, R.; Pugh, C.

    1999-10-01

    A summary of the recently completed International Comparative Assessment Study of Pressurized-Thermal-Shock in Reactor Pressure Vessels (RPV PTS ICAS) is presented here to record the results in actual and comparative fashions. Within the DFM task, where account was taken of material properties and boundary conditions, reasonable agreement was obtained in linear-elastic and elastic-plastic analysis results. Linear elastic analyses and J-estimation schemes were shown to provide conservative estimates of peak crack driving force when compared with those obtained using complex three-dimensional (3D) finite element analyses. Predictions of RT NDT generally showed less scatter than that observed in crack driving force calculations due to the fracture toughness curve used for fracture assessment in the transition temperature region. Observed scatter in some analytical results could be traced mainly to a misinterpretation of the thermal expansion coefficient data given for the cladding and base metal. Also, differences in some results could be due to a quality assurance problem related to procedures for approximating the loading data given in the Problem Statement. For the PFM task, linear-elastic solutions were again shown to be conservative with respect to elastic-plastic solutions (by a factor of 2 to 4). Scatter in solutions obtained using the same computer code was generally attributable to differences in input parameters, e.g. standard deviations for the initial value of RT NDT , as well as for nickel and copper content. In the THM task, while there was a high degree of scatter during the early part of the transient, reasonable agreement in results was obtained during the latter part of the transient. Generally, the scatter was due to differences in analytical approaches used by participants, which included correlation-based engineering methods, system codes and three-dimensional computational fluids dynamics codes. Some of the models used to simulate condensation

  11. International inequalities in per capita CO{sub 2} emissions: a decomposition methodology by Kaya factors

    Energy Technology Data Exchange (ETDEWEB)

    Duro, J.A. [Universitat Rovira i Virgili, Reus (Spain). Dept. d' Economia; Universitat de Barcelona (Spain). Inst. de Analisis Economico; Padilla, E. [Universitat de Barcelona (Spain). Dept. d' Economia Aplicada

    2006-03-15

    In this paper, we provide a methodology for decomposing international inequalities in per capita CO{sub 2} emissions into Kaya (multiplicative) factors and two interaction terms. We use the Theil index of inequality and show that this decomposition methodology can be extended for analyzing between- and within-group inequality components. We can thus analyze the factors behind inequalities in per capita CO{sub 2} emissions across countries, between groups of countries and within groups of countries. The empirical illustration for international data suggests some points. Firstly, international inequality in per capita CO{sub 2} emissions is mainly attributable to inequalities in per capita income levels, which helps to explain its recent reduction, while differences in carbon intensity of energy and energy intensity have made a less significant contribution. This result is strongly influenced by the performance of China and India. Secondly, the between-group inequality component, which is the biggest component, is also largely explained by the income factor. Thirdly, the within-group inequality component increased slightly during the period, something mainly due to the change in the income factor and the interaction terms in a few regions. (author)

  12. International inequalities in per capita CO2 emissions: a decomposition methodology by Kaya factors

    International Nuclear Information System (INIS)

    Duro, J.A.; Universitat de Barcelona; Padilla, E.

    2006-01-01

    In this paper, we provide a methodology for decomposing international inequalities in per capita CO 2 emissions into Kaya (multiplicative) factors and two interaction terms. We use the Theil index of inequality and show that this decomposition methodology can be extended for analyzing between- and within-group inequality components. We can thus analyze the factors behind inequalities in per capita CO 2 emissions across countries, between groups of countries and within groups of countries. The empirical illustration for international data suggests some points. Firstly, international inequality in per capita CO 2 emissions is mainly attributable to inequalities in per capita income levels, which helps to explain its recent reduction, while differences in carbon intensity of energy and energy intensity have made a less significant contribution. This result is strongly influenced by the performance of China and India. Secondly, the between-group inequality component, which is the biggest component, is also largely explained by the income factor. Thirdly, the within-group inequality component increased slightly during the period, something mainly due to the change in the income factor and the interaction terms in a few regions. (author)

  13. The climate fund. Some notions on the socio-economic impacts of greenhouse gas emissions and emission reductions in an international context

    International Nuclear Information System (INIS)

    Tol, R.S.J.; Van der Burg, T.; Jansen, H.M.A.; Verbruggen, H.

    1995-05-01

    The title project investigates the possibility of setting up an international climate fund and the way in which this could be arranged. A climate fund is a potential method to enhance the efficiency and efficacy of the reduction of the increase in the amount of greenhouse gases (GHGs) in the atmosphere. It would allow countries to transfer capital, for instance through the here proposed climate fund, and to redistribute the damages caused by global warming. This project focuses on the economic aspects of a climate fund, although some attention will also be given to its political feasibility. The system of tradeable emission permits, of which joint implementation is often seen as a pilot phase, presumes that fixed emission targets exist. In this report the emissions are not prefixed, but optimised in a cost-benefit analysis in which the impact of international capital transfer is examined. In order to determine the impact of international capital transfer on the efficiency and efficacy on optimal greenhouse gas emission reduction, three building blocks are needed. The first block concerns the costs of climate change, or the benefits of climate change control. The second block concerns the costs of emission reduction. The third block is the model to integrate costs and benefits, and calculate the optimal emission control with and without international capital transfers. The project is split into four conceptual phases. In the first phase, a literature survey has been performed of the socio-economic costs and benefits of greenhouse gas emission reductions, with a particular focus on the international distribution of costs and benefits. In the second phase, the costs and benefits are modelled in the Climate Framework for Uncertainty, Negotiation and Distribution (FUND). In the third phase the optimal emission reductions are calculated with and without international capital transfers in several game-theoretic settings. (Abstract Truncated)

  14. International marine and aviation bunker fuel. Trends, ranking of countries and comparison with national CO2 emission

    International Nuclear Information System (INIS)

    Olivier, J.G.J.; Peters, J.A.H.W.

    1999-01-01

    This report summarises and characterises fuel consumption and associated CO2 emissions from international transport based on energy statistics compiled by the International Energy Agency (IEA). Shares in 1990 and 1970-1995 trends in national and global bunker fuel consumption and associated CO2 emissions are analysed for marine and air transport. Also, the global total of international transport emissions are compared with national emissions and domestic transport emissions. During the last 25 years the average global annual increase was for marine bunkers about 0.8% and for aviation emissions about 3.3%. Annual variations per country of marine bunker fuel use larger than of aviation fuel use, sometimes more than 50%. However, the distinction between fuel use for domestic and for international aviation is more difficult to monitor. The dominant fuel in marine bunker fuel consumption is residual fuel oil ('heavy fuel oil'). The share of diesel oil has slowly increased from 11% in 1970 to 20% in 1990. Aviation fuels sold are predominantly jet fuel ('jet kerosene'). The small share of aviation gasoline is slowly decreasing: from about 4% in 1970 to 1.3% in 1990. Carbon dioxide emissions from combustion of international marine bunker fuels and aviation contributed in 1990 globally about 1.8% and 2.4% expressed as percentage of global total anthropogenic emissions (excluding deforestation). However, aviation emissions include an unknown part of domestic aviation. When comparing with total transport emissions, then international transport has a share of 20%. For both marine and aviation bunker fuel, the Top-10 of largest consuming countries account for about 2/3 of the global total; the Top-25 countries cover already 85% or more of global total CO2 emissions

  15. RESOLVING THE BRIGHT HCN(1–0) EMISSION TOWARD THE SEYFERT 2 NUCLEUS OF M51: SHOCK ENHANCEMENT BY RADIO JETS AND WEAK MASING BY INFRARED PUMPING?

    International Nuclear Information System (INIS)

    Matsushita, Satoki; Trung, Dinh-V-; Boone, Frédéric; Krips, Melanie; Lim, Jeremy; Muller, Sebastien

    2015-01-01

    We present high angular resolution observations of the HCN(1-0) emission (at ∼1'' or ∼34 pc), together with CO J = 1-0, 2-1, and 3-2 observations, toward the Seyfert 2 nucleus of M51 (NGC 5194). The overall HCN(1-0) distribution and kinematics are very similar to that of the CO lines, which have been indicated as the jet-entrained molecular gas in our past observations. In addition, high HCN(1-0)/CO(1-0) brightness temperature ratio of about unity is observed along the jets, similar to that observed at the shocked molecular gas in our Galaxy. These results strongly indicate that both diffuse and dense gases are entrained by the jets and outflowing from the active galactic nucleus. The channel map of HCN(1-0) at the systemic velocity shows a strong emission right at the nucleus, where no obvious emission has been detected in the CO lines. The HCN(1-0)/CO(1-0) brightness temperature ratio at this region reaches >2, a value that cannot be explained considering standard physical/chemical conditions. Based on our calculations, we suggest infrared pumping and possibly weak HCN masing, but still requiring an enhanced HCN abundance for the cause of this high ratio. This suggests the presence of a compact dense obscuring molecular gas in front of the nucleus of M51, which remains unresolved at our ∼1'' (∼34 pc) resolution, and consistent with the Seyfert 2 classification picture

  16. RESOLVING THE BRIGHT HCN(1–0) EMISSION TOWARD THE SEYFERT 2 NUCLEUS OF M51: SHOCK ENHANCEMENT BY RADIO JETS AND WEAK MASING BY INFRARED PUMPING?

    Energy Technology Data Exchange (ETDEWEB)

    Matsushita, Satoki [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China); Trung, Dinh-V- [Institute of Physics, Vietnamese Academy of Science and Technology, 10, Daotan, BaDinh, Hanoi (Viet Nam); Boone, Frédéric [Université de Toulouse, UPS-OMP, IRAP, F-31400 Toulouse (France); Krips, Melanie [Institute de Radio Astronomie Millimétrique, 300 Rue de la Piscine, F-38406 Saint Martin d' Hères (France); Lim, Jeremy [Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong); Muller, Sebastien [Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, SE-43992 Onsala (Sweden)

    2015-01-20

    We present high angular resolution observations of the HCN(1-0) emission (at ∼1'' or ∼34 pc), together with CO J = 1-0, 2-1, and 3-2 observations, toward the Seyfert 2 nucleus of M51 (NGC 5194). The overall HCN(1-0) distribution and kinematics are very similar to that of the CO lines, which have been indicated as the jet-entrained molecular gas in our past observations. In addition, high HCN(1-0)/CO(1-0) brightness temperature ratio of about unity is observed along the jets, similar to that observed at the shocked molecular gas in our Galaxy. These results strongly indicate that both diffuse and dense gases are entrained by the jets and outflowing from the active galactic nucleus. The channel map of HCN(1-0) at the systemic velocity shows a strong emission right at the nucleus, where no obvious emission has been detected in the CO lines. The HCN(1-0)/CO(1-0) brightness temperature ratio at this region reaches >2, a value that cannot be explained considering standard physical/chemical conditions. Based on our calculations, we suggest infrared pumping and possibly weak HCN masing, but still requiring an enhanced HCN abundance for the cause of this high ratio. This suggests the presence of a compact dense obscuring molecular gas in front of the nucleus of M51, which remains unresolved at our ∼1'' (∼34 pc) resolution, and consistent with the Seyfert 2 classification picture.

  17. Bubble Dynamics and Shock Waves

    CERN Document Server

    2013-01-01

    This volume of the Shock Wave Science and Technology Reference Library is concerned with the interplay between bubble dynamics and shock waves. It is divided into four parts containing twelve chapters written by eminent scientists. Topics discussed include shock wave emission by laser generated bubbles (W Lauterborn, A Vogel), pulsating bubbles near boundaries (DM Leppinen, QX Wang, JR Blake), interaction of shock waves with bubble clouds (CD Ohl, SW Ohl), shock propagation in polydispersed bubbly liquids by model equations (K Ando, T Colonius, CE Brennen. T Yano, T Kanagawa,  M Watanabe, S Fujikawa) and by DNS (G Tryggvason, S Dabiri), shocks in cavitating flows (NA Adams, SJ Schmidt, CF Delale, GH Schnerr, S Pasinlioglu) together with applications involving encapsulated bubble dynamics in imaging (AA Doinikov, A Novell, JM Escoffre, A Bouakaz),  shock wave lithotripsy (P Zhong), sterilization of ships’ ballast water (A Abe, H Mimura) and bubbly flow model of volcano eruptions ((VK Kedrinskii, K Takayama...

  18. Internal standardization in atomic-emission spectrometry using inductively coupled plasma

    International Nuclear Information System (INIS)

    Moore, G.L.

    1985-01-01

    The principle of internal standardization has been used in quantitative analytical emission spectroscopy since 1925 to minimize the errors arising from fluctuations in sample preparation, excitation-source conditions, and detection parameters. Although modern spectroscopic excitation sources are far more stable and electronic detection methods are more precise than before, the system for the introduction of the sample in spectrometric analysis using inductively coupled plasma (ICP) introduces significant errors, and internal standardization can still play a useful role in improving the overall precision of the analytical results. The criteria for the selection of the elements to be used as internal standards in arc and spark spectrographic analysis apply to a much lesser extent in ICP-spectrometric analysis. Internal standardization is recommended for use in routine ICP-simultaneous spectrometric analysis to improve its accuracy and precision and to provide a monitor for the reassurance of the analyst. However, the selection of an unsuitable reference element can result in misuse of the principle of internal standardization and, although internal standardization can be applied when a sequential monochromator is used, the main sources of error will not be minimized

  19. Shock tubes and waves; Proceedings of the Sixteenth International Symposium, Rheinisch-Westfaelische Technische Hochschule, Aachen, Federal Republic of Germany, July 26-31, 1987

    Science.gov (United States)

    Groenig, Hans

    Topics discussed in this volume include shock wave structure, propagation, and interaction; shocks in condensed matter, dusty gases, and multiphase media; chemical processes and related combustion and detonation phenomena; shock wave reflection, diffraction, and focusing; computational fluid dynamic code development and shock wave application; blast and detonation waves; advanced shock tube technology and measuring technique; and shock wave applications. Papers are presented on dust explosions, the dynamics of shock waves in certain dense gases, studies of condensation kinetics behind incident shock waves, the autoignition mechanism of n-butane behind a reflected shock wave, and a numerical simulation of the focusing process of reflected shock waves. Attention is also given to the equilibrium shock tube flow of real gases, blast waves generated by planar detonations, modern diagnostic methods for high-speed flows, and interaction between induced waves and electric discharge in a very high repetition rate excimer laser.

  20. CRITERIA POLLUTANT EMISSIONS FROM INTERNAL COMBUSTION ENGINES IN THE NATURAL GAS INDUSTRY VOLUME II. APPENDICES A-I

    Science.gov (United States)

    The report summarizes emission factors for criteria pollutants (NOx, CO, CH4, C2H6, THC, NMHC, and NMEHC) from stationary internal combustion engines and gas turbines used in the natural gas industry. The emission factors were calculated from test results from five test campaigns...

  1. Emissions trading in international aviation. Possible design options for an emissions trading scheme and their impact on climate change and the aviation industry

    International Nuclear Information System (INIS)

    Deuber, Odette; Cames, Martin

    2003-01-01

    According to the Intergovernmental Panel on Climate Change (IPCC), the contribution of aviation to global warm-ing was 3.5 % in 1992. Considering the average growth rate of 4 % per year, the share might be more than doubled by the end of the first commitment period of the Kyoto Protocol (2012). However, due to difficulties in allocating emissions from international aviation to individual countries, these emissions are exempt from commitments under the Kyoto Protocol, although in Article 2.2 the Parties to the Protocol are obliged to stabilize and reduce greenhouse gas emissions from international aviation. To comply with this obligation, the introduction of emissions trading in international aviation is being discussed within the International Civil Aviation Organisation (ICAO). This paper analyses the design options of such an emissions trading scheme and its impact on climate change and the aviation industry. Among other matters, it discusses issues such as open and closed emissions trading schemes, coverage of gases, initial allocation of allowances and possible caps for the aviation industry. It is based on a re-search project that has been carried out on behalf of the German Federal Environmental Agency. The paper reveals that despite complex tropospheric and stratospheric interactions, as well as allocation problems, there are adequate structural options for the design of an emissions trading scheme. Given an adequate structure, emissions trading offers a great incentive to optimise flight routes not only according to economic but also to climatic factors. Consequently, the system would effectively reduce the contribution of aviation to climate change

  2. Ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance and their application on energy-saving kettle

    International Nuclear Information System (INIS)

    Zhang, Jianyi; Fan, Xi’an; Lu, Lei; Hu, Xiaoming; Li, Guangqiang

    2015-01-01

    Highlights: • The ferrites based infrared radiation coating was prepared by HVOF for the first time. • The infrared radiation coatings were applied firstly on the household kettle. • The bonding strength between the coating and substrate could reach 30.7 MPa. • The coating kept intact when cycle reached 27 by quenching from 1000 °C using water. • The energy-saving efficiency of the kettle with coating could reach 30.5%. - Abstract: Starting from Fe 2 O 3 , MnO 2 , Co 2 O 3 and NiO powders, the ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance were successfully prepared on the surface of carbon steel by high velocity oxy-fuel spraying (HVOF). The coating thickness was about 120–150 μm and presented a typical flat lamellar structure. The coating surface was rough and some submicron grade grains distributed on it. The infrared emissivity of the ferrites based coating by HVOF was over 0.74 in 3–20 μm waveband at 800 °C, which was obviously higher than that of the coating by brushing process in the short waveband. The bonding strength was 30.7 MPa between the coating and substrate, which was five times more than that of conventional coatings by brushing process. The combined effect of the superior bonding strength, typical lamellar structure, pre-existing microcracks and newly generated pores made the cycle times reach 27 when the coating samples were quenched from 1000 °C using water. Lastly, the infrared radiation coatings were applied on the underside of household kettle, and the energy-saving efficiency could reach 30.5%. The ferrites based infrared radiation coatings obtained in this work are good candidates for saving energy in the field of cookware and industrial high temperature furnace

  3. The international research progress of Ammonia(NH3) emissions and emissions reduction technology in farmland ecosystem

    Science.gov (United States)

    Yang, W. Z.; Jiao, Y.

    2017-03-01

    NH3 is the important factor leading to the grey haze, and one of the main causes of environmental problems of serious ecological imbalance, such as acid rain and air quality deterioration. The fertilizer excessive application of the current farmland results NH3 emissions intensity greatly. In order to clear the farmland NH3 emissions research status and achievements, the literature of farmland NH3 emission related were retrievaled by the SCI journals and Chinese science citation database. Some factors of NH3 emission were analyzed such as soil factors, climate factors and farmland management measures. The research progress was inductived on farmland NH3 emission reduction technology. The results will help to clarify farmland NH3 emissions research progress. The theoretical guidance was provided on the future of farmland NH3 emissions research.

  4. Change in CO2 emission and its transmissions between Korea and Japan using international input-output analysis

    International Nuclear Information System (INIS)

    Rhee, Hae-Chun; Chung, Hyun-Sik

    2006-01-01

    This paper is intended to analyze CO 2 transmission between Japan and South Korea through international trade based on 1990 and 1995 international input-output data. It applied a residual-free structural decomposition method proposed by Chung and Rhee [Chung, H.S., Rhee, H.C., 2001. A residual-free decomposition of the sources of carbon dioxide emissions: a case of the Korean industries. Energy 26 (1), 15-30] to emission-related international input-output analysis for the first time in the decomposition studies. This paper is a case study regarding the manner and the extent to which CO 2 emissions are influenced by international trade between Japan (an Annex I country) and South Korea (a non-Annex I country), which is of particular interest for the carbon leakage issue. In this paper, we attempted to show which factors contributed to the changes in emission of the major greenhouse gas in South Korea and Japan. The changes in emission are analyzed in terms of emission intensity, input techniques, demand composition, and trade structures. According to our analysis, South Korea, a non-Annex I country, has more energy-intensive production structures than Japan, an Annex I country. South Korea's trade pattern with Japan reflects these production features, resulting in the Korea's comparative advantage in emission intensive products, though the degree has somewhat mitigated in 1995 compared to 1990. (author)

  5. After the Hague, Bonn and Marrakech: uncertainties on the future international market of emission permits

    International Nuclear Information System (INIS)

    Kitous, A.; Criqui, P.; Blanchard, O.

    2002-01-01

    The purpose of this article is to present an economic assessment, step by step, of the successive developments of the negotiation on weather changes since the Kyoto protocol in 1997 until the agreement achieved in Marrakech during the seventh Conference of the Parties (COP 7) in November 2001. The analysis covers the international market of emission rights, a key mechanism of the Protocol, the purpose of which is to facilitate the Parties' compliance with their undertakings, by introducing flexibility to improve the economic efficiency of emission reduction. However, it now appears that despite the Marrakech agreement in November 2001, the system is weakened by the withdrawal of the USA decided by President G.W. Bush in March 2001, following COP 6 in The Hague, and by a potential excess of permits due to the economic recession of transition countries since the early nineties (hot air). As things stands, the establishment of the market between the countries taking part in the process will undoubtedly require some management of this hot air between transition countries (Eastern Europe and Ex USSR) and the other Parties of appendix B still involved in the process. The uncertainties weighing on the future market of emission permits strengthen the strategic significance of the implementation of effective reduction policies within those regions and particularly within Europe. (authors)

  6. Isotopic dependence of the fragments' internal temperatures determined from multifragment emission

    Science.gov (United States)

    Souza, S. R.; Donangelo, R.

    2018-05-01

    The internal temperatures of fragments produced by an excited nuclear source are investigated by using the microcanonical version of the statistical multifragmentation model, with discrete energy. We focus on the fragments' properties at the breakup stage, before they have time to deexcite by particle emission. Since the adopted model provides the excitation energy distribution of these primordial fragments, it allows one to calculate the temperatures of different isotope families and to make inferences about the sensitivity to their isospin composition. It is found that, due to the functional form of the nuclear density of states and the excitation energy distribution of the fragments, proton-rich isotopes are hotter than neutron-rich isotopes. This property has been taken to be an indication of earlier emission of the former from a source that cools down as it expands and emits fragments. Although this scenario is incompatible with the prompt breakup of a thermally equilibrated source, our results reveal that the latter framework also provides the same qualitative features just mentioned. Therefore they suggest that this property cannot be taken as evidence for nonequilibrium emission. We also found that this sensitivity to the isotopic composition of the fragments depends on the isospin composition of the source, and that it is weakened as the excitation energy of the source increases.

  7. 40 CFR 60.4203 - How long must my engines meet the emission standards if I am a stationary CI internal combustion...

    Science.gov (United States)

    2010-07-01

    ... emission standards if I am a stationary CI internal combustion engine manufacturer? 60.4203 Section 60.4203... Combustion Engines Emission Standards for Manufacturers § 60.4203 How long must my engines meet the emission standards if I am a stationary CI internal combustion engine manufacturer? Engines manufactured by...

  8. Improving cost-effectiveness and facilitating participation of developing countries in international emissions trading

    International Nuclear Information System (INIS)

    Bohm, P.

    2003-01-01

    Cost-effectiveness is a crucial requirement for meaningful agreements on international climate change policy. This is also borne out in the wording of the Framework Convention of Climate Change and, in particular, the Kyoto Protocol (KP), see UNFCCC (1992) and UN (1997). However, the KP - as it stands after COP7 in Marrakech - is not fully cost-effective, although it may eventually turn out to be the only politically feasible, 'most cost-effective', first step in international climate change policy. The successor to the COP7 version of the KP may be a renegotiated protocol, if the COP7 version fails to be ratified by enough countries to enter into force, or it may be the treaty to be designed for a second commitment period. Four dimensions in which cost-effectiveness may be improved in a treaty that succeeds the KP are discussed here. They all relate to international emissions trading (IET) which is likely to be the most significant instrument for attaining cost-effective reductions in aggregate greenhouse gas (GHG) emissions. It is important for a climate treaty to be able to attract as many developing countries to IET as possible and achieve this as soon as possible. This would have to occur at essentially no cost to them. Only with developing countries onboard can the world community get full access to their low-cost options for emission reductions. A first aspect to be discussed here is related to identifying a cost-effective approach to attain that goal (Section 1). Another aspect concerns the role of the Clean Development Mechanism (CDM) in this context (Section 2). A third issue is to evaluate the consequences for cost-effectiveness of introducing a Commitment Period Reserve to limit 'overselling' (Section 3). A final one deals with the increase in flexibility that would follow from allowing not only banking but also borrowing of Assigned Amount Units (AAUs) (Section 4). While the first two issues refer directly to developing countries, the last two will be

  9. Numerical modeling of slow shocks

    International Nuclear Information System (INIS)

    Winske, D.

    1987-01-01

    This paper reviews previous attempt and the present status of efforts to understand the structure of slow shocks by means of time dependent numerical calculations. Studies carried out using MHD or hybrid-kinetic codes have demonstrated qualitative agreement with theory. A number of unresolved issues related to hybrid simulations of the internal shock structure are discussed in some detail. 43 refs., 8 figs

  10. The model for calculation of emission and imisson of air pollutants from vehicles with internal combustion engine

    International Nuclear Information System (INIS)

    Tashevski, Done; Dimitrovski, Mile

    1994-01-01

    The model for calculation of emission and immision of air pollutants from vehicles with internal combustion engine on the crossroads in urban environments, with substitution of a great number of exhaust-pipes with one chimney in the centre of the crossroad has been made. The whole calculation of the pollution sources mentioned above is, in the fact, the calculation of the emission and imisson of pollutants from point sources of pollution. (author)

  11. Shock absorber

    International Nuclear Information System (INIS)

    Nemeth, J.D.

    1981-01-01

    A shock absorber for the support of piping and components in a nuclear power plant is described. It combines a high degree of stiffness under sudden shocks, e.g. seismic disturbances, with the ability to allow for thermal expansion without resistance when so required. (JIW)

  12. 40 CFR 60.4231 - What emission standards must I meet if I am a manufacturer of stationary SI internal combustion...

    Science.gov (United States)

    2010-07-01

    ... I am a manufacturer of stationary SI internal combustion engines or equipment containing such... Stationary Spark Ignition Internal Combustion Engines Emission Standards for Manufacturers § 60.4231 What emission standards must I meet if I am a manufacturer of stationary SI internal combustion engines or...

  13. Asymmetric learning by doing and dynamically efficient policy: implications for domestic and international emissions permit trading of allocating permits usefully

    International Nuclear Information System (INIS)

    Read, Peter

    2000-01-01

    Learning by doing leads to cost reductions as suppliers move down the 'experience curve'. This results in a beneficial supply side inter-temporal externality that, for dynamic efficiency, requires a higher incentive for abatement innovations than the penalty on emissions. This effect can be achieved by a dedicated emissions tax or by a proportionate abatement obligation or by allocating permits usefully. The latter arrangement is compatible with the effective cap on emissions that is secured by an emissions trading scheme. Each of the three possibilities results in a reduced loss of international competitivity in policy-committed regions, in less 'leakage, and in more technology transfer. Implications for trading in emissions permits and in project-related credits are discussed. (Author)

  14. Internal modifications to reduce pollutant emissions from marine engines. A numerical approach

    Science.gov (United States)

    Lamas, M. I.; Rodríguez, C. G.; Rodríguez, J. D.; Telmo, J.

    2013-12-01

    Taking into account the increasingly stringent legislation on emissions from marine engines, this work aims to analyze several internal engine modifications to reduce NOx (nitrogen oxides) and other pollutants. To this end, a numerical model was employed to simulate the operation cycle and characterize the exhaust gas composition. After a preliminary validation process was carried out using experimental data from a four-stroke, medium-speed marine engine, the numerical model was employed to study the influence of several internal modifications, such as water addition from 0 to 100% water to fuel ratios, exhaust gas recirculation from 0 to 100% EGR rates, modification of the overlap timing from 60 to 120°, modification of the intake valve closing from 510 to 570°, and modification of the cooling water temperature from 70 to 90 oC. NOx was reduced by nearly 100%. As expected, it was found that, by lowering the combustion temperature, there is a notable reduction in NOx, but an increase in CO (carbon monoxide), HC (hydrocarbons) and consumption.

  15. Internal modifications to reduce pollutant emissions from marine engines. A numerical approach

    Directory of Open Access Journals (Sweden)

    M.I. Lamas

    2013-12-01

    Full Text Available Taking into account the increasingly stringent legislation on emissions from marine engines, this work aims to analyze several internal engine modifications to reduce NOx (nitrogen oxides and other pollutants. To this end, a numerical model was employed to simulate the operation cycle and characterize the exhaust gas composition. After a preliminary validation process was carried out using experimental data from a four-stroke, medium-speed marine engine, the numerical model was employed to study the influence of several internal modifications, such as water addition from 0 to 100% water to fuel ratios, exhaust gas recirculation from 0 to 100% EGR rates, modification of the overlap timing from 60 to 120°, modification of the intake valve closing from 510 to 570°, and modification of the cooling water temperature from 70 to 90 °C. NOx was reduced by nearly 100%. As expected, it was found that, by lowering the combustion temperature, there is a notable reduction in NOx, but an increase in CO (carbon monoxide, HC (hydrocarbons and consumption.

  16. demystifying the shock of shocking

    African Journals Online (AJOL)

    (with a pulse), atrial fibrillation and atrial flutter. The energy dose in cardioversion is less (0.5. - 2 J/kg) than in defibrillation (2 - 4 J/kg). In cardioversion the shock is discharged synchronously with the native R wave of the patient. Without synchronisation,. VF can be induced if a shock is delivered during the refractory period ...

  17. Hypovolemic shock

    Science.gov (United States)

    ... the person's position unless they are in immediate danger. Do not give fluids by mouth. If person ... the patient with shock. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: ...

  18. Shock absorber

    International Nuclear Information System (INIS)

    Housman, J.J.

    1978-01-01

    A shock absorber is described for use in a hostile environment at the end of a blind passage for absorbing impact loads. The shock absorber includes at least one element which occupies the passage and which is comprised of a porous brittle material which is substantially non-degradable in the hostile environment. A void volume is provided in the element to enable the element to absorb a predetermined level of energy upon being crushed due to impact loading

  19. Cradle-to-gate greenhouse gas emissions of battery electric and internal combustion engine vehicles in China

    International Nuclear Information System (INIS)

    Qiao, Qinyu; Zhao, Fuquan; Liu, Zongwei; Jiang, Shuhua; Hao, Han

    2017-01-01

    Highlights: •Cradle-to-gate greenhouse gas emissions of internal combustion engine and battery electric vehicles are compared. •Greenhouse gas emissions of battery electric vehicles are 50% higher than internal combustion engine vehicles. •Traction battery production causes about 20% greenhouse gas emissions increase. •10% variations of curb weight, electricity and Li-ion battery production affect the results by 7%, 4% and 2%. •Manufacturing technique improvement, vehicle recycling and energy structure optimization are major mitigation opportunities. -- Abstract: Electric drive vehicles are equipped with totally different propulsion systems compared with conventional vehicles, for which the energy consumption and cradle-to-gate greenhouse gas emissions associated with vehicle production could substantially change. In this study, the life cycle energy consumption and greenhouse gas emissions of vehicle production are compared between battery electric and internal combustion engine vehicles in China’s context. The results reveal that the energy consumption and greenhouse gas emissions of a battery electric vehicle production range from 92.4 to 94.3 GJ and 15.0 to 15.2 t CO 2 eq, which are about 50% higher than those of an internal combustion engine vehicle, 63.5 GJ and 10.0 t CO 2 eq. This substantial change can be mainly attributed to the production of traction batteries, the essential components for battery electric vehicles. Moreover, the larger weight and different weight distribution of materials used in battery electric vehicles also contribute to the larger environmental impact. This situation can be improved through the development of new traction battery production techniques, vehicle recycling and a low-carbon energy structure.

  20. Verification of the Danish emission inventory data by national and international data comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Fauser, P.; Thomsen, Marianne; Nielsen, Ole-Kenneth; Winther, M.; Gyldenkaerne, S.; Hoffmann, L.; Lyck, E.; Boll Illerup, J.

    2007-08-15

    Danish emission intensity values, activity values and implied emission factors for identified key source categories are compared with corresponding values for the EU-15 countries (excluding Luxemburg). The emission values for all countries are based on national greenhouse gas inventories for the years 1990 (base year), 1997 and 2003 provided by the UNFCCC. The comparison is based on a proposed verification procedure that is designed for identifying emission indicators and evaluating data consistency and reliability for the energy and industry sectors. For all sectors the method gives good possibility for checking emission levels and consistency in time trends. (au)

  1. A study of internal oxidation in carburized steels by glow discharge optical emission spectroscopy and scanning electron microscopy

    CERN Document Server

    An, X; Rainforth, W M; Chen, L

    2003-01-01

    The internal oxidation of Cr-Mn carburizing steel was studied. Internal oxidation was induced using a commercial carburizing process. Sputter erosion coupled with glow discharge optical emission spectroscopy (GDOES) was used to determine the depth profile elemental distribution within the internal oxidation layer (<10 mu m). In addition, scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS) studies were carried out on selected sputter eroded surfaces. Oxide type was identified primarily by transmission electron microscopy (TEM). The carburized surface was found to consist of a continuous oxide layer, followed by a complex internal oxidation layer, where Cr and Mn oxides were found to populate grain boundaries in a globular form in the near surface region. At greater depths (5-10 mu m), Si oxides formed as a grain boundary network. The internal oxides (mainly complex oxides) grew quickly during the initial stages of the carburizing process (2 h, 800 deg. C+3 h, 930 deg. C). G...

  2. International trade and air pollution: estimating the economic costs of air emissions from waterborne commerce vessels in the United States.

    Science.gov (United States)

    Gallagher, Kevin P

    2005-10-01

    Although there is a burgeoning literature on the effects of international trade on the environment, relatively little work has been done on where trade most directly effects the environment: the transportation sector. This article shows how international trade is affecting air pollution emissions in the United States' shipping sector. Recent work has shown that cargo ships have been long overlooked regarding their contribution to air pollution. Indeed, ship emissions have recently been deemed "the last unregulated source of traditional air pollutants". Air pollution from ships has a number of significant local, national, and global environmental effects. Building on past studies, we examine the economic costs of this increasing and unregulated form of environmental damage. We find that total emissions from ships are largely increasing due to the increase in foreign commerce (or international trade). The economic costs of SO2 pollution range from dollars 697 million to dollars 3.9 billion during the period examined, or dollars 77 to dollars 435 million on an annual basis. The bulk of the cost is from foreign commerce, where the annual costs average to dollars 42 to dollars 241 million. For NOx emissions the costs are dollars 3.7 billion over the entire period or dollars 412 million per year. Because foreign trade is driving the growth in US shipping, we also estimate the effect of the Uruguay Round on emissions. Separating out the effects of global trade agreements reveals that the trade agreement-led emissions amounted to dollars 96 to dollars 542 million for SO2 between 1993 and 2001, or dollars 10 to dollars 60 million per year. For NOx they were dollars 745 million for the whole period or dollars 82 million per year. Without adequate policy responses, we predict that these trends and costs will continue into the future.

  3. A Study of the Social Effects of International GHG Emission Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Seung Jick [Korea Energy Economics Institute, Euiwang (Korea)

    2000-12-01

    International efforts of greenhouse gas mitigation to prevent climate change reduce not only emission of greenhouse gases, but emission of the pollutants such as SO{sub 2}, NOx, CO, PM, and O{sub 3}. These pollutants are known to be responsible for the negative impact on human health and ecosystem. Ancillary benefits and costs should be included in the calculation of net benefit of greenhouse gas mitigation policies. Ancillary benefit, on the one hand, directly affects the optimal level of greenhouse gas mitigation. On the other hand, the size of ancillary benefit could play a crucial role in adopting greenhouse gas mitigation policies, especially for the Non-Annex I countries because ancillary benefits are directly realized in the country implementing those policies. Ancillary benefit is estimated using both top-down approach and bottom-up approach. Most of ancillary benefit result from benefits related to the health effect. However, ancillary benefits are estimated quite differently between studies. Ancillary benefits in Europe are estimated from $300/TC to $600/TC, while in USA they are estimated from $3/TC to $300/TC. In the developing countries ancillary benefits vary in the range of $6/TC to $300/TC. Differences in the population density, and the exposure rate are partially responsible for the difference in the size of estimated ancillary benefits. However the main source of difference in the estimates are related to the baseline, methodological differences in monetization of the benefits among others. Despite the importance of ancillary benefits is of no doubt, it is too early to argue that the size of ancillary benefit is sufficient to offset the greenhouse gas mitigation cost such as decrease in GDP and the employment rate. Estimation of ancillary benefits could be improved by incorporating geographical and time factors and the differences in environmental and industrial policies. Further improvement could be made by maintaining consistency in assumptions

  4. 75 FR 51569 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-08-20

    ... Air Pollutants for Reciprocating Internal Combustion Engines; Final Rule #0;#0;Federal Register / Vol... for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines AGENCY: Environmental... hazardous air pollutants for existing stationary spark ignition reciprocating internal combustion engines...

  5. 78 FR 54606 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2013-09-05

    ... Combustion Engines; New Source Performance Standards for Stationary Internal Combustion Engines AGENCY... hazardous air pollutants for stationary reciprocating internal combustion engines and the standards of performance for stationary internal combustion engines. Subsequently, the EPA received three petitions for...

  6. Carbon Emission Mitigation Potentials of Different Policy Scenarios and Their Effects on International Aviation in the Korean Context

    Directory of Open Access Journals (Sweden)

    Sungwook Yoon

    2016-11-01

    Full Text Available The objective of this study is to seek better policy options for greenhouse gas (GHG emission reduction in Korea’s international aviation industry by analyzing economic efficiency and environmental effectiveness with a system dynamics (SD model. Accordingly, we measured airlines sales and CO2 emission reductions to evaluate economic efficiency and environmental effectiveness, respectively, for various policies. The results show that the average carbon emission reduction rates of four policies compared to the business-as-usual (BAU scenario between 2015 and 2030 are 4.00% (Voluntary Agreement, 7.25% (Emission Trading System or ETS-30,000, 8.33% (Carbon Tax or CT-37,500, and 8.48% (Emission Charge System or EC-30,000. The average rate of decrease in airline sales compared to BAU for the ETS policy is 0.1% at 2030. Our results show that the ETS approach is the most efficient of all the analyzed CO2 reduction policies in economic terms, while the EC approach is the best policy to reduce GHG emissions. This study provides a foundation for devising effective response measures pertaining to GHG reduction and supports decision making on carbon tax and carbon credit pricing.

  7. The impact of international trade on China's industrial carbon emissions since its entry into WTO

    International Nuclear Information System (INIS)

    Ren, Shenggang; Yuan, Baolong; Ma, Xie; Chen, Xiaohong

    2014-01-01

    This paper employs the input–output (IO) approach to analyze the scale and structure of embodied carbon emissions of China's 19 industry sectors during 2001–2011 and constructs a regression model to establish the relationship between energy intensity, per capita output, trade openness, foreign direct investment (FDI), trade comparative advantage, environmental regulation, technology, and CO 2 emission intensity. Our results suggest that: China's international embodied carbon emission balance has been in a state of continuous growth for the period 2001–2011, and China has become a pollution haven; the relationship between per capita output and CO 2 emission is inverse N-typed and China's industries are in the rising stage of the curve; FDI and trade comparative advantage are two main elements boosting China's carbon emissions; trade openness, environmental regulation, and technology will lower the growth rate of China's industrial carbon emissions (ICEs). Consequently, China's policies should center on adjusting the industry structure and scale of FDI inflows, transforming industries with trade comparative advantages into a clean type, facilitating environmental regulation level, and bringing in and developing low-carbon technology to avert China from being a pollution haven. - Highlights: • We first employ a panel dataset of 19 industry sectors in China. • The relationship between per capita output and CO 2 emission is inverse N-typed. • China’s industries are in the rising stage of the inverse N-typed curve. • FDI and trade comparative advantage increase industrial carbon emissions in China

  8. Formation of (Xe2H)* centers in solid Xe via recombination: nonstationary luminescence and 'internal electron emission'

    International Nuclear Information System (INIS)

    Savchenko, E.V.; Khyzhniy, I.V.; Uyutov, S.A.; Gumenchuk, G.B.; Ponomarev, A.N.; Bondybey, V.E.; Beyer, M.K.

    2010-01-01

    The formation of excimers (Xe 2 H) * in solid Xe doped with molecular hydrogen under electron beam is studied using the original two-stage technique of nonstationary (NS) cathodoluminescence (CL) in combination with the current activation spectroscopy method - thermally stimulated exoelectron emission (TSEE). Charged species were generated using a high-density electron beam. The species produced were then probed with a low density beam on gradual sample heating. The near UV emission of the (Xe 2 H) * was used to monitor the neutralization process. It is found that the temperature behavior of the NS CL band of (Xe 2 H) * clearly correlates with the yield of TSEE measured after identical pre-irradiation of the sample. The fingerprints of the thermally stimulated detrapping of electrons - 'internal electron emission' in the spectrum of NS CL point to the essential role of neutralization reaction in the stability of the proton solvated by rare-gas atoms.

  9. Toxic shock syndrome

    Science.gov (United States)

    Staphylococcal toxic shock syndrome; Toxic shock-like syndrome; TSLS ... Toxic shock syndrome is caused by a toxin produced by some types of staphylococcus bacteria. A similar problem, called toxic shock- ...

  10. Bow shock data analysis

    Science.gov (United States)

    Zipf, Edward C.; Erdman, Peeter W.

    1994-08-01

    The University of Pittsburgh Space Physics Group in collaboration with the Army Research Office (ARO) modeling team has completed a systematic organization of the shock and plume spectral data and the electron temperature and density measurements obtained during the BowShock I and II rocket flights which have been submitted to the AEDC Data Center, has verified the presence of CO Cameron band emission during the Antares engine burn and for an extended period of time in the post-burn plume, and have adapted 3-D radiation entrapment codes developed by the University of Pittsburgh to study aurora and other atmospheric phenomena that involve significant spatial effects to investigate the vacuum ultraviolet (VUV) and extreme ultraviolet (EUV) envelope surrounding the re-entry that create an extensive plasma cloud by photoionization.

  11. Marine nitrous oxide emissions: An unknown liability for the international water sector

    Science.gov (United States)

    Reliable estimates of anthropogenic greenhouse gas (GHG) emissions are essential for setting effective climate policy at both the sector and national level. Current IPCC Guidelines for calculating nitrous oxide (N2O) emissions from sewage management are both highly uncertain and ...

  12. International greenhouse gas emissions trading. Who should be held liable for the non-compliance by sellers?

    International Nuclear Information System (INIS)

    Zhang, Zhong Xiang

    1999-01-01

    Article 17 of the Kyoto Protocol authorizes emissions trading, but the rules governing emissions trading have been deferred to subsequent conferences. In designing and implementing an international greenhouse gas (GHG) emissions trading scheme, assigning liability has been considered to be one of the most challenging issues. This article discusses a variety of the rules for accountability under international GHG emissions trading. It indicates that a 'buyer beware' liability is effective only to the extent that it puts additional pressure on sellers to comply with their commitments because after all sellers exercise great, if not complete, control over whether or not they comply with their commitments. Because putting such a pressure on sellers to develop effective compliance systems is not without costs to buyers, a 'buyer beware' liability should thus be imposed only in the case where non-compliance of sellers is virtually certain to occur. Moreover, in determining the optimal combination of these not-mutually-exclusive rules for accountability that are discussed in the article, the marginal benefits of adding one rule needs to be weighted against the increased costs of doing so. 12 refs

  13. Limiting overselling in international emissions trading 1: Costs and environmental impacts of alternative proposals

    Energy Technology Data Exchange (ETDEWEB)

    Haites, E.; Missfeldt, F.

    2002-07-01

    Emission trading allows a country with an emission limitation commitment, an Annex B Party, to sell parts of its assigned amount (AAUs) to other Annex B Parties. If the seller subsequently does not have sufficient AAUs to cover its actual emissions it will be subject to the penalties for non-compliance. The revenue from the sale of AAUs may exceed the sanctions for non-compliance if these penalties are weak or difficult to enforce. Under these circumstances emission trading enables a country to benefit financially through non-compliance. Liability proposals seek to ensure that non-compliance is not rewarded, by limiting sales of AAUs to amounts surplus to the seller's compliance needs. This study develops and applies a model to assess the performance of different liability proposals. A simple model based on the Emissions Projection and Policy Analysis (EPPA) model of the Massachusetts Institute of Technology is used for the analysis. (BA)

  14. International markets for greenhouse gas emission reduction policies - possibilities for integrating developing countries

    DEFF Research Database (Denmark)

    Halsnæs, K.; Olhoff, A.

    2005-01-01

    Greenhouse gas (GHG) emissions are affecting a global common: the climate, and as a global environmental problem with a public good character it provides attractive opportunities for minimising control costs through the use of emission trading markets. This paper introduces cost and benefit princ...... principles that can be applied to the assessment of global markets for GHG emission reduction options and evaluates the scope for and the potential economic gains of such markets.......Greenhouse gas (GHG) emissions are affecting a global common: the climate, and as a global environmental problem with a public good character it provides attractive opportunities for minimising control costs through the use of emission trading markets. This paper introduces cost and benefit...

  15. Forced-air warming design: evaluation of intake filtration, internal microbial buildup, and airborne-contamination emissions.

    Science.gov (United States)

    Reed, Mike; Kimberger, Oliver; McGovern, Paul D; Albrecht, Mark C

    2013-08-01

    Forced-air warming devices are effective for the prevention of surgical hypothermia. However, these devices intake nonsterile floor-level air, and it is unknown whether they have adequate filtration measures to prevent the internal buildup or emission of microbial contaminants. We rated the intake filtration efficiency of a popular current-generation forced-air warming device (Bair Hugger model 750, Arizant Healthcare) using a monodisperse sodium chloride aerosol in the laboratory. We further sampled 23 forced-air warming devices (same model) in daily hospital use for internal microbial buildup and airborne-contamination emissions via swabbing and particle counting. Laboratory testing found the intake filter to be 63.8% efficient. Swabbing detected microorganisms within 100% of the forced-air warming blowers sampled, with isolates of coagulase-negative staphylococci, mold, and micrococci identified. Particle counting showed 96% of forced-air warming blowers to be emitting significant levels of internally generated airborne contaminants out of the hose end. These findings highlight the need for upgraded intake filtration, preferably high-efficiency particulate air filtration (99.97% efficient), on current-generation forced-air warming devices to reduce contamination buildup and emission risks.

  16. Towards a Novel Integrated Approach for Estimating Greenhouse Gas Emissions in Support of International Agreements

    Science.gov (United States)

    Reimann, S.; Vollmer, M. K.; Henne, S.; Brunner, D.; Emmenegger, L.; Manning, A.; Fraser, P. J.; Krummel, P. B.; Dunse, B. L.; DeCola, P.; Tarasova, O. A.

    2016-12-01

    In the recently adopted Paris Agreement the community of signatory states has agreed to limit the future global temperature increase between +1.5 °C and +2.0 °C, compared to pre-industrial times. To achieve this goal, emission reduction targets have been submitted by individual nations (called Intended Nationally Determined Contributions, INDCs). Inventories will be used for checking progress towards these envisaged goals. These inventories are calculated by combining information on specific activities (e.g. passenger cars, agriculture) with activity-related, typically IPCC-sanctioned, emission factors - the so-called bottom-up method. These calculated emissions are reported on an annual basis and are checked by external bodies by using the same method. A second independent method estimates emissions by translating greenhouse gas measurements made at regionally representative stations into regional/global emissions using meteorologically-based transport models. In recent years this so-called top-down approach has been substantially advanced into a powerful tool and emission estimates at the national/regional level have become possible. This method is already used in Switzerland, in the United Kingdom and in Australia to estimate greenhouse gas emissions and independently support the national bottom-up emission inventories within the UNFCCC framework. Examples of the comparison of the two independent methods will be presented and the added-value will be discussed. The World Meteorological Organization (WMO) and partner organizations are currently developing a plan to expand this top-down approach and to expand the globally representative GAW network of ground-based stations and remote-sensing platforms and integrate their information with atmospheric transport models. This Integrated Global Greenhouse Gas Information System (IG3IS) initiative will help nations to improve the accuracy of their country-based emissions inventories and their ability to evaluate the

  17. Take-off engine particle emission indices for in-service aircraft at Los Angeles International Airport.

    Science.gov (United States)

    Moore, Richard H; Shook, Michael A; Ziemba, Luke D; DiGangi, Joshua P; Winstead, Edward L; Rauch, Bastian; Jurkat, Tina; Thornhill, Kenneth L; Crosbie, Ewan C; Robinson, Claire; Shingler, Taylor J; Anderson, Bruce E

    2017-12-19

    We present ground-based, advected aircraft engine emissions from flights taking off at Los Angeles International Airport. 275 discrete engine take-off plumes were observed on 18 and 25 May 2014 at a distance of 400 m downwind of the runway. CO 2 measurements are used to convert the aerosol data into plume-average emissions indices that are suitable for modelling aircraft emissions. Total and non-volatile particle number EIs are of order 10 16 -10 17 kg -1 and 10 14 -10 16 kg -1 , respectively. Black-carbon-equivalent particle mass EIs vary between 175-941 mg kg -1 (except for the GE GEnx engines at 46 mg kg -1 ). Aircraft tail numbers recorded for each take-off event are used to incorporate aircraft- and engine-specific parameters into the data set. Data acquisition and processing follow standard methods for quality assurance. A unique aspect of the data set is the mapping of aerosol concentration time series to integrated plume EIs, aircraft and engine specifications, and manufacturer-reported engine emissions certifications. The integrated data enable future studies seeking to understand and model aircraft emissions and their impact on air quality.

  18. Take-off engine particle emission indices for in-service aircraft at Los Angeles International Airport

    Science.gov (United States)

    Moore, Richard H.; Shook, Michael A.; Ziemba, Luke D.; Digangi, Joshua P.; Winstead, Edward L.; Rauch, Bastian; Jurkat, Tina; Thornhill, Kenneth L.; Crosbie, Ewan C.; Robinson, Claire; Shingler, Taylor J.; Anderson, Bruce E.

    2017-12-01

    We present ground-based, advected aircraft engine emissions from flights taking off at Los Angeles International Airport. 275 discrete engine take-off plumes were observed on 18 and 25 May 2014 at a distance of 400 m downwind of the runway. CO2 measurements are used to convert the aerosol data into plume-average emissions indices that are suitable for modelling aircraft emissions. Total and non-volatile particle number EIs are of order 1016-1017 kg-1 and 1014-1016 kg-1, respectively. Black-carbon-equivalent particle mass EIs vary between 175-941 mg kg-1 (except for the GE GEnx engines at 46 mg kg-1). Aircraft tail numbers recorded for each take-off event are used to incorporate aircraft- and engine-specific parameters into the data set. Data acquisition and processing follow standard methods for quality assurance. A unique aspect of the data set is the mapping of aerosol concentration time series to integrated plume EIs, aircraft and engine specifications, and manufacturer-reported engine emissions certifications. The integrated data enable future studies seeking to understand and model aircraft emissions and their impact on air quality.

  19. Power generation and gaseous emissions performance of an internal combustion engine fed with blends of soybean and beef tallow biodiesel.

    Science.gov (United States)

    Schirmer, Waldir Nagel; Gauer, Mayara Ananda; Tomaz, Edson; Rodrigues, Paulo Rogério Pinto; de Souza, Samuel Nelson Melegari; Chaves, Luiz Inácio; Villetti, Lucas; Olanyk, Luciano Zart; Cabral, Alexandre Rodrigues

    2016-01-01

    This study aimed to compare the performance of an internal combustion engine fed with blends of biodiesel produced from soybean and diesel, and blends of biodiesel produced from beef tallow and diesel. Performance was evaluated in terms of power generated at low loading conditions (0.5, 1.0 and 1.5 kW) and emission of organic and inorganic pollutants. In order to analyse inorganic gases (CO, SO2 and NOx), an automatic analyser was used and the organic emissions (benzene, toluene, ethylbenzene and xylene - BTEX) were carried out using a gas chromatograph. The results indicate that the introduction of the two biodiesels in the fuel caused a reduction in CO, SO2 and BTEX emissions. In addition, the reduction was proportional to the increase in loading regime. Beef tallow biodiesels presented better results regarding emission than soybean biodiesels. The use of pure biodiesels also presented a net reduction in pollutant gas emissions without hindering the engine generator performance.

  20. A new comparison between the life cycle greenhouse gas emissions of battery electric vehicles and internal combustion vehicles

    International Nuclear Information System (INIS)

    Ma Hongrui; Balthasar, Felix; Tait, Nigel; Riera-Palou, Xavier; Harrison, Andrew

    2012-01-01

    Electric vehicles have recently been gaining increasing worldwide interest as a promising potential long-term solution to sustainable personal mobility; in particular, battery electric vehicles (BEVs) offer zero tailpipe emissions. However, their true ability to contribute to greenhouse gas (GHG) emissions reductions can only be properly assessed by comparing a life cycle assessment of their GHG emissions with a similar assessment for conventional internal combustion vehicles (ICVs). This paper presents an analysis for vehicles typically expected to be introduced in 2015 in two example markets (the UK and California), taking into account the impact of three important factors: •Like-for-like vehicle comparison and effect of real-world driving conditions. •Accounting for the GHG emissions associated with meeting the additional electricity demand for charging the batteries. •GHG emissions associated with vehicle manufacture, disposal, etc. This work demonstrates that all of these factors are important and emphasises that it is therefore crucial to clearly define the context when presenting conclusions about the relative GHG performance of BEVs and ICVs – such relative performance depends on a wide range of factors, including the marginal regional grid GHG intensity, vehicle size, driving pattern, loading, etc. - Highlights: ► Develops new insights into the life cycle GHG emissions of electric vehicles. ► Addresses like-for-like vehicle comparison and effect of real-world driving. ► Accounts for marginal GHG intensity of the electricity used to charge EVs. ► Accounts for the GHG emissions associated with vehicle manufacture and disposal.

  1. 5th international exhaust gas and particulate emissions forum. Proceedings; 5. Internationales Forum Abgas- und Partikelemissionen. Beitraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-12-11

    The Proceedings of the 5th International Exhaust Gas and Particulate Emissions Forum contains 22 printed contributions as well as a CD-ROM. The titles of them are: (1) Diesel Emissions Control in the United States - 2010 and Beyond; (2) The MBE90 commercial vehicle engine for EPA '07 emissions regulations; (3) Concepts for engines and exhaust-gas cleaning systems for heavy duty trucks of the future; (4) HD Engine Technology for Near-Zero Emissions and Lowest Cost of Ownership; (5) (Partially-) Homogeneous Diesel Combustion; (6) Exhaust gas sensors for NOx storage catalysts and ammonia-SCR systems; (7) Sensors for modern exhaust gas after-treatment systems; (8) New reducing agents for low NOx-SCR Techno-logy; (9) Exhaust gas Aftertreatment on Lean Burn Gasoline Direct Injection Engines: The System of TWC and NOx-Storage Catalyst; (10) New Platinum/Palladium based catalyzed filter technologies for future passenger car applications; (11) Development of a Roadway Hydrocarbon Sorption Model and Characterization of a Novel PM Generator; (12) Requirements for current and future particulate measurement instrumentation from the point of view of the Physikalisch-Technische Bundesanstalt; (13) Standardized dilution conditions for gravimetric PM sampling - measures to assure results that correlate; (14) Particle Counting according PMP; (15) Future high-confidence measurement of diesel particulate emissions for approval and development; (16) New developments in optical instrumentation for exhaust gas; (17) Simultaneous Detection of Gaseous and Particulate Exhaust Components by Photoacoustic Spectroscopy; (18) Boundaries of modern exhaust gas instrumentation; (19) Raising quality and reducing application effort through efficient data input to the particulate filter load model for a EURO5 diesel car; (20) Stop-start operation of diesel engines - modified require-ment for exhaust gas after-treatment?; (21) Particulates emission with Biodiesel B30 impact on CSF management; (22

  2. 5th international exhaust gas and particulate emissions forum. Proceedings; 5. Internationales Forum Abgas- und Partikelemissionen. Beitraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-12-11

    The Proceedings of the 5th International Exhaust Gas and Particulate Emissions Forum contains 22 printed contributions as well as a CD-ROM. The titles of them are: (1) Diesel Emissions Control in the United States - 2010 and Beyond; (2) The MBE90 commercial vehicle engine for EPA '07 emissions regulations; (3) Concepts for engines and exhaust-gas cleaning systems for heavy duty trucks of the future; (4) HD Engine Technology for Near-Zero Emissions and Lowest Cost of Ownership; (5) (Partially-) Homogeneous Diesel Combustion; (6) Exhaust gas sensors for NOx storage catalysts and ammonia-SCR systems; (7) Sensors for modern exhaust gas after-treatment systems; (8) New reducing agents for low NOx-SCR Techno-logy; (9) Exhaust gas Aftertreatment on Lean Burn Gasoline Direct Injection Engines: The System of TWC and NOx-Storage Catalyst; (10) New Platinum/Palladium based catalyzed filter technologies for future passenger car applications; (11) Development of a Roadway Hydrocarbon Sorption Model and Characterization of a Novel PM Generator; (12) Requirements for current and future particulate measurement instrumentation from the point of view of the Physikalisch-Technische Bundesanstalt; (13) Standardized dilution conditions for gravimetric PM sampling - measures to assure results that correlate; (14) Particle Counting according PMP; (15) Future high-confidence measurement of diesel particulate emissions for approval and development; (16) New developments in optical instrumentation for exhaust gas; (17) Simultaneous Detection of Gaseous and Particulate Exhaust Components by Photoacoustic Spectroscopy; (18) Boundaries of modern exhaust gas instrumentation; (19) Raising quality and reducing application effort through efficient data input to the particulate filter load model for a EURO5 diesel car; (20) Stop-start operation of diesel engines - modified require-ment for exhaust gas after-treatment?; (21) Particulates emission with Biodiesel B30 impact on CSF management; (22

  3. On Shocks Driven by High-mass Planets in Radiatively Inefficient Disks. III. Observational Signatures in Thermal Emission and Scattered Light

    Science.gov (United States)

    Hord, Blake; Lyra, Wladimir; Flock, Mario; Turner, Neal J.; Mac Low, Mordecai-Mark

    2017-11-01

    Recent observations of the protoplanetary disk around the Herbig Be star HD 100546 show two bright features in infrared (H and {L}{\\prime } bands) at about 50 au,with one so far unexplained. We explore the observational signatures of a high-mass planet causing shock heating in order to determine if it could be the source of the unexplained infrared feature in HD 100546. More fundamentally, we identify and characterize planetary shocks as an extra, hitherto ignored, source of luminosity in transition disks. The RADMC-3D code is used to perform dust radiative transfer calculations on the hydrodynamical disk models, including volumetric heating. A stronger shock heating rate by a factor of 20 would be necessary to qualitatively reproduce the morphology of the second infrared source. Instead, we find that the outer edge of the gap carved by the planet heats up by about 50% relative to the initial reference temperature, which leads to an increase in the scale height. The bulge is illuminated by the central star, producing a lopsided feature in scattered light, as the outer gap edge shows an asymmetry in density and temperature attributable to a secondary spiral arm launched not from the Lindblad resonances but from the 2:1 resonance. We conclude that high-mass planets lead to shocks in disks that may be directly observed, particularly at wavelengths of 10 μm or longer, but that they are more likely to reveal their presence in scattered light by puffing up their outer gap edges and exciting multiple spiral arms.

  4. Condensed matter at high shock pressures

    International Nuclear Information System (INIS)

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-01-01

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N 2 , CO, SiO 2 -aerogel, H 2 O, and C 6 H 6 . The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab

  5. International Shock Congress (1st) and Annual Society Meeting (10th) Held in Montreal, Canada on 7-11 June 1987

    Science.gov (United States)

    1987-10-01

    hemoconcentration (Hct). 14 BENEFICIAL ACTIONS OF DEFIBROTIDE , A PROSTACYCLIN ENHANCING AGENT, IN HEMORRHAGIC SHOCK. Haim Bitterman*, David J. Lefer* and Allan M...eicosanoid with beneficial effects in ischemia and shock. We studied the effects of defibrotide , a new antithrombotic agent which enhances PG! 2 release...bleedout volume, followed by reinfusion of all remaining shed blood. Defibrotide (4 mg/kg) was given as an i.v. bolus at 30 min post-hemorrhage followed

  6. International comparison of CO2 emission trends in the iron and steel industry

    International Nuclear Information System (INIS)

    Yeonbae, Kim; Worrell, E.

    2002-01-01

    In this paper, we present an in-depth decomposition analysis of trends in CO 2 emissions in the iron and steel industry using physical indicators. Physical indicators allow a detailed analysis of intra- sectoral trends, in contrast to the mostly used monetary indicators. Detailed decomposition analysis makes it possible to link developments in energy intensity to technology change and (indirectly) to policy. We present an analysis for the iron and steel industry in seven countries, i.e. Brazil, China, India (developing countries), Mexico and South Korea (newly industrialized countries) and the United States (industrialized country). We found substantial differences in energy efficiency among these countries. In most countries the increased (or decreased) production was the main contributor to changes in CO 2 emissions, while energy-efficiency was the main factor reducing emission intensities of steel production in almost all countries. Changes in power generation contributed to a reduction of specific emissions in the case of South Korea only. (Author)

  7. Analysis of the carbon monoxide emission by internal combustion engines using LPG as a fuel

    International Nuclear Information System (INIS)

    Dimitrovski, Mile

    2002-01-01

    In this paper a description of the toxic emission reduction as well as a reduction of the toxic components presence in exhaust gases is presented. The analysis of the alternative gaseous fuels application as one of the possibilities for a toxic emission reduction is given. In addition, the results of the CO concentration measurements for two cases: first using gasoline, than liquefied petrol gas (LPG) as a fuel are presented. (Author)

  8. Do oil shocks predict economic policy uncertainty?

    Science.gov (United States)

    Rehman, Mobeen Ur

    2018-05-01

    Oil price fluctuations have influential role in global economic policies for developed as well as emerging countries. I investigate the role of international oil prices disintegrated into structural (i) oil supply shock, (ii) aggregate demand shock and (iii) oil market specific demand shocks, based on the work of Kilian (2009) using structural VAR framework on economic policies uncertainty of sampled markets. Economic policy uncertainty, due to its non-linear behavior is modeled in a regime switching framework with disintegrated structural oil shocks. Our results highlight that Indian, Spain and Japanese economic policy uncertainty responds to the global oil price shocks, however aggregate demand shocks fail to induce any change. Oil specific demand shocks are significant only for China and India in high volatility state.

  9. Update on emissions and environmental impacts from the international fleet of ships: the contribution from major ship types and ports

    Directory of Open Access Journals (Sweden)

    S. B. Dalsøren

    2009-03-01

    Full Text Available A reliable and up-to-date ship emission inventory is essential for atmospheric scientists quantifying the impact of shipping and for policy makers implementing regulations and incentives for emission reduction. The emission modelling in this study takes into account ship type and size dependent input data for 15 ship types and 7 size categories. Global port arrival and departure data for more than 32 000 merchant ships are used to establish operational profiles for the ship segments. The modelled total fuel consumption amounts to 217 Mt in 2004 of which 11 Mt is consumed in in-port operations. This is in agreement with international sales statistics. The modelled fuel consumption is applied to develop global emission inventories for CO2, NO2, SO2, CO, CH4, VOC (Volatile Organic Compounds, N2O, BC (Black Carbon and OC (Organic Carbon. The global emissions from ships at sea and in ports are distributed geographically, applying extended geographical data sets covering about 2 million global ship observations and global port data for 32 000 ships. In addition to inventories for the world fleet, inventories are produced separately for the three dominating ship types, using ship type specific emission modelling and traffic distributions.

    A global Chemical Transport Model (CTM was used to calculate the environmental impacts of the emissions. We find that ship emissions is a dominant contributor over much of the world oceans to surface concentrations of NO2 and SO2. The contribution is also large over some coastal zones. For surface ozone the contribution is high over the oceans but clearly also of importance over Western North America (contribution 15–25% and Western Europe (5–15%. The contribution to tropospheric column ozone is up to 5–6%. The overall impact of ship emissions on global methane lifetime is large due to the high NOx emissions. With

  10. Study of gas emission from the internal chambers of cryogenic equipment

    International Nuclear Information System (INIS)

    Matyash, Y.I.; Fel'dman, R.G.; Ivakhnenko, Z.N.; Myasnikov, V.M.

    1986-01-01

    One of the methods of improving the efficiency of cryogenic gas equipment (CGE) is adsorption purification of the working medium. The type and quantity of adsorben can be decided after knowing the qualitative and quantitative nature of gas emissions. Gas emissions were studied by the chromatographic method using a heat-conduction detectory. This method made it possible to determine simultaneously the impurities which differ significantly in terms of physicochemical properties. It was established that carbon dioxide and hydrocarbons are continuously emitted in the gaseous medium of the CGE at a constant rate. For the type of machine which was studied, the rates of gas emission were as follows: carbon dioxide and ethane - 0.2 mg/h; ethylene and methane - 0.1 mg/h; propylene, N-butane, and isobutane - 0.2 mg/h

  11. Buyer Liability and Voluntary Inspections in International Greenhouse Gas Emissions Trading. A Laboratory Study

    International Nuclear Information System (INIS)

    Cason, T.N.

    2003-01-01

    This paper reports a preliminary laboratory experiment in which traders make investments to increase the reliability of tradable instruments that represent greenhouse gas emissions allowances. In one half of the sessions these investments are unobservable, while in the other half traders can invite costless and accurate inspections that make reliability investments public. We implement a buyer liability rule, so that if emissions reductions are unreliable (i.e., sellers default), the buyer of the allowances cannot redeem them to cover emissions. We find that allowing inspections significantly increases the reliability investment rate and overall efficiency. Prices of uninspected allowances usually trade at a substantial discount due to the buyer liability rule, which provides a strong market incentive for sellers to invest in reliability

  12. Indicators for the international comparison of energy consumption and greenhouse-gas emissions

    International Nuclear Information System (INIS)

    Hohmann, R.; Steiner, S.; Koch, P.

    2007-11-01

    This comprehensive report for the Swiss Federal Office of Energy (SFOE) examines the energy consumption and greenhouse-gas emissions of various Swiss economical sectors including industry, services, households and traffic. Comparisons are made with the corresponding areas in the European Union and other countries. In spite of the relatively good situation in the Swiss industrial sector, further investigation is recommended. Room for improvement in the services sector is mentioned and average performance as far as energy consumption in households is concerned is noted. It is estimated that a considerable potential for improvement is available in this sector. Motorised traffic is quoted as being the main source of greenhouse-gas emissions, Switzerland being the second worst European country in this respect. Estimates are made concerning the potential for emission reductions in the various areas

  13. International trade and carbon emissions: The role of Chinese institutional and policy reforms.

    Science.gov (United States)

    Andersson, Fredrik N G

    2018-01-01

    The carbon dioxide embodied in Chinese exports to developed countries increased rapidly from 1995 to 2008. We test the extent to which institutional reforms in China can explain this increase. We focus on five areas of reforms: trade liberalization, environmental institutions, legal and property rights, institutional risk and exchange rate policy. Our results show that trade liberalization, weak environmental institutions, exchange rate policy, and legal and property rights affect emissions. Our results also indicate that the lack of reform in the utilities sector is an important factor in the rapid increase in embodied emissions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Emissions Trading Regimes and Incentives to Participate in International Climate Agreements

    International Nuclear Information System (INIS)

    Buchner, B.; Carraro, C.

    2003-11-01

    This paper analyses whether different emissions trading regimes provide different incentives to participate in a cooperative climate agreement. Different incentive structures are discussed for those countries, namely the US, Russia and China, that are most important in the climate negotiation process. Our analysis confirms the conjecture that, by appropriately designing the emission trading regime, it is possible to enhance the incentives to participate in a climate agreement. Therefore, participation and optimal policy should be jointly analysed. Moreover, our results show that the US, Russia and China have different most preferred climate coalitions and therefore adopt conflicting negotiation strategies

  15. A study on the spectrum analyzing of internal leak in valve for power plant using acoustic emission method

    International Nuclear Information System (INIS)

    Lee, Sang Guk; Lee, Sun Ki; Lee, Jun Shin; Sohn, Seok Man

    2004-01-01

    The purpose of this study is to estimate the availability of acoustic emission method to the internal leak of the valves at nuclear power plants. The acoustic emission method was applied to the valves at the site, and the background noise was measured for the abnormal plant condition. From the comparison of the background noise data with the experimental results as to relation between leak flow and acoustic signal, the minimum leak flow rates that can be detected by acoustic signal was suggested. When the background levels are higher than the acoustic signal, the method described below was considered that the analysis the remainder among the background noise frequency spectrum and the acoustic signal spectrum become a very useful leak detection method. A few experimental examples of the spectrum analysis that varied the background noise characteristic were given

  16. AMPLITUDE FLUCTUATIONS OF SPONTANEOUS OTOACOUSTIC EMISSIONS CAUSED BY INTERNAL AND EXTERNALLY APPLIED NOISE SOURCES

    NARCIS (Netherlands)

    WIT, HP

    1993-01-01

    The simplest description for the generator of a spontaneous otoacoustic emission (SOAE) is that of a single (isolated) limit-cycle oscillator. Evidence is given that this description is too simple. And it is concluded that study of systems of coupled oscillators is needed to obtain more insight in

  17. Reduction of heat losses from greenhouses by means of internal blinds with low thermal emissivity

    NARCIS (Netherlands)

    Meijer, J.

    1980-01-01

    Heat losses in greenhouses may be substantially reduced by the use of heat reflecting blinds. Quantitative results are obtained solving a mathematical heat flow model by numerical methods. Special attention has been given to the emissivity and transmittance of the screen and the ventilation through

  18. Mapping the international flows of GHG emissions within a more feasible consumption-based framework

    DEFF Research Database (Denmark)

    Caro, Dario; Pulselli, Federico; Borghesi, Simone

    2017-01-01

    and consumed outside its boundaries. A relevant example is the export from China to consumers located in the USA, Japan, and Germany. A focus on the Mediterranean area, that resulted as a net importer of CO2 embodied in traded goods, identifies the export of emissions from Italy and Spain to France and from...

  19. Acoustic and Emission Characteristics of Small, High-Speed Internal Combustion Engines

    Science.gov (United States)

    1981-07-01

    The intent of this study is to obtain information on small high-speed engines so that their effect on the urban environment may be assessed, and if necessary, programs devised to reduce the noise and other emissions from vehicles using these highly d...

  20. A study of internal oxidation in carburized steels by glow discharge optical emission spectroscopy and scanning electron microscopy

    International Nuclear Information System (INIS)

    An, X; Cawley, J.; Rainforth, W.M.; Chen, L.

    2003-01-01

    The internal oxidation of Cr-Mn carburizing steel was studied. Internal oxidation was induced using a commercial carburizing process. Sputter erosion coupled with glow discharge optical emission spectroscopy (GDOES) was used to determine the depth profile elemental distribution within the internal oxidation layer (<10 μm). In addition, scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS) studies were carried out on selected sputter eroded surfaces. Oxide type was identified primarily by transmission electron microscopy (TEM). The carburized surface was found to consist of a continuous oxide layer, followed by a complex internal oxidation layer, where Cr and Mn oxides were found to populate grain boundaries in a globular form in the near surface region. At greater depths (5-10 μm), Si oxides formed as a grain boundary network. The internal oxides (mainly complex oxides) grew quickly during the initial stages of the carburizing process (2 h, 800 deg. C+3 h, 930 deg. C). GDOES proved to be an excellent tool for the quantification of oxidation and element distribution as a function of depth, particularly when combined with SEM and TEM to identify oxide type and morphology

  1. Observation of a flare-generated shock wave at 9.7 AU by Pioneer 10

    International Nuclear Information System (INIS)

    Dryer, M.; Shea, M.A.; Smart, D.F.; Collard, H.R.; Mihalov, J.D.; Wolfe, J.H.; Warwick, J.W.

    1978-01-01

    The period March 15 to May 15, 1976, was declared in advance to be the internationally recognized Study of Traveling Interplanetary Phenomena Interval II. A variety of ground- and space-based equipment was requested to make coordinated studies during this part of the minimum of solar cycle 20. Following an absence of solar activity for a long period, several type II radio bursts on March 20, 1976, produced by two solar flares behind the east limb heralded a series of solar interplanetary, and terrestrial events. These solar radio astronomical observations were followed by non-Io-associated radio emission from Jupiter and solar wind plasma detection at Pioneer 10 at 9.7 AU of an apparent shock wave on March 30 and April 9, 1976, respectively. In view of the fact that the solar flares on March 20 were essentially at central meridian with respect to Jupiter and Pioneer 10 and also that the sun was extremely inactive prior to that date we consider the circumstantial evidence that at least one solar-flare-generated shock wave propagated to the position of Pioneer 10. The average velocities of this shock wave, together with the inferred type II velocity, support previous observations and theory concerning the rapid deceleration and survival of interplanetary shock waves to distances at least as large as approx.10 AU. It is therefore believed that dissipation (other than that within shocks themselves) plays an insignificant role in shock wave dynamics within the solar wind

  2. A generalized modal shock spectra method for spacecraft loads analysis. [internal loads in a spacecraft structure subjected to a dynamic launch environment

    Science.gov (United States)

    Trubert, M.; Salama, M.

    1979-01-01

    Unlike an earlier shock spectra approach, generalization permits an accurate elastic interaction between the spacecraft and launch vehicle to obtain accurate bounds on the spacecraft response and structural loads. In addition, the modal response from a previous launch vehicle transient analysis with or without a dummy spacecraft - is exploited to define a modal impulse as a simple idealization of the actual forcing function. The idealized modal forcing function is then used to derive explicit expressions for an estimate of the bound on the spacecraft structural response and forces. Greater accuracy is achieved with the present method over the earlier shock spectra, while saving much computational effort over the transient analysis.

  3. Diaphragmless shock wave generators for industrial applications of shock waves

    Science.gov (United States)

    Hariharan, M. S.; Janardhanraj, S.; Saravanan, S.; Jagadeesh, G.

    2011-06-01

    The prime focus of this study is to design a 50 mm internal diameter diaphragmless shock tube that can be used in an industrial facility for repeated loading of shock waves. The instantaneous rise in pressure and temperature of a medium can be used in a variety of industrial applications. We designed, fabricated and tested three different shock wave generators of which one system employs a highly elastic rubber membrane and the other systems use a fast acting pneumatic valve instead of conventional metal diaphragms. The valve opening speed is obtained with the help of a high speed camera. For shock generation systems with a pneumatic cylinder, it ranges from 0.325 to 1.15 m/s while it is around 8.3 m/s for the rubber membrane. Experiments are conducted using the three diaphragmless systems and the results obtained are analyzed carefully to obtain a relation between the opening speed of the valve and the amount of gas that is actually utilized in the generation of the shock wave for each system. The rubber membrane is not suitable for industrial applications because it needs to be replaced regularly and cannot withstand high driver pressures. The maximum shock Mach number obtained using the new diaphragmless system that uses the pneumatic valve is 2.125 ± 0.2%. This system shows much promise for automation in an industrial environment.

  4. INTERFERENCE OF COUNTERPROPAGATING SHOCK WAVES

    Directory of Open Access Journals (Sweden)

    P. V. Bulat

    2015-03-01

    Full Text Available The subject of study. We examined the interaction of counterpropagating shock waves. The necessity of counterpropagating shock waves studying occurs at designing of high Mach number modern internal compression air intakes, Ramjets with subsonic and supersonic combustion, in asymmetrical supersonic nozzles and in some other cases. In a sense, this problem is a generalization of the case of an oblique shock reflection from the wall or from the plane of symmetry. With the renewed vigor, the interest to this problem emerged at the end of the 90s. This was due to the start of the programs for flight study at hypersonic speeds. The first experiments performed with air intakes, which realized the interaction of counterpropagating shock waves have shown that the change in flow velocity is accompanied by abrupt alteration of shock-wave structure, the occurrence of nonstationary and oscillatory phenomena. With an increase of flow velocity these phenomena undesirable for aircraft structure became more marked. The reason is that there are two fundamentally different modes of interaction of counterpropagating shock waves: a four-wave regular and a five-wave irregular. The transition from one mode to another can be nonstationary abrupt or gradual, it can also be accompanied by hysteresis. Main results. Criteria for the transition from regular reflection of counterpropagating shock waves to irregular are described: the criterion of von Neumann and the stationary Mach configuration criterion. We described areas in which the transition from one reflection type to another is possible only in abrupt way, as well as areas of possible gradual transition. Intensity dependences of the reflected shock waves from the intensity of interacting counterpropagating shocks were given. Qualitative pictures of shock-wave structures arising from the interaction of counterpropagating shock waves were shown. Calculation results of the intensity of outgoing gas

  5. Patient safety against radioelectric emissions internal and external at the Hospital Universitario de Canarias

    International Nuclear Information System (INIS)

    Febles Santana, V.; Martin Diaz, M. a.; Miguel Bilbao, S. de; Suarez Rodriguez, D. S.; Hernandez Armas, J. A.; Fernandez de Aldecoa, J. C.; Ramos Gonzalez, V.

    2011-01-01

    Electromagnetic fields (EMF) present in a health center, must be known and to be controlled so that your levels are at all times below the limits established by law in the face of patient safety, health personnel and other users. In addition, they may be the source of interference on medical equipment and, consequently, the cause of errors in diagnosis or treatments applied to the sick. This paper presents the results of the measurements made at the Hospital Universitario de Canarias (HUC) EMF levels of radio emissions from the antennas installed in our hospital (Tetra, pagers, and wi-fi) and external emissions from most relevant, either because of their widespread use (mobile phones) or the proximity to the Hospital of the antennas (commercial broadcasters).

  6. International Experiences and Frameworks to Support Country-Driven Low-Emissions Development

    Energy Technology Data Exchange (ETDEWEB)

    Benioff, R.; Cochran, J.; Cox, S.

    2012-08-01

    Countries can use low-emission development strategies (LEDS) to advance sustainable development, promote private-sector growth, and reduce greenhouse gas emissions. This paper proposes a framework -- or support infrastructure -- to enable the efficient exchange of LEDS-related knowledge and technical assistance. Under the proposed framework, countries share LEDS-related resources via coordinating forums, 'knowledge platforms,' and networks of experts and investors. The virtual 'knowledge platforms' foster learning by allowing countries to communicate with each other and share technical reports, data, and analysis tools in support of LEDS development. Investing in all elements of the framework in an integrated fashion increases the efficacy of support for country-driven LEDS.

  7. Shock Prevention

    Science.gov (United States)

    1978-01-01

    The electrician pictured is installing a General Electric Ground Fault Interrupter (GFI), a device which provides protection against electrical shock in the home or in industrial facilities. Shocks due to defective wiring in home appliances or other electrical equipment can cause severe burns, even death. As a result, the National Electrical Code now requires GFIs in all new homes constructed. This particular type of GFI employs a sensing element which derives from technology acquired in space projects by SCI Systems, Inc., Huntsville, Alabama, producer of sensors for GE and other manufacturers of GFI equipment. The sensor is based on the company's experience in developing miniaturized circuitry for space telemetry and other spacecraft electrical systems; this experience enabled SCI to package interruptor circuitry in the extremely limited space available and to produce sensory devices at practicable cost. The tiny sensor measures the strength of the electrical current and detects current differentials that indicate a fault in the functioning of an electrical system. The sensing element then triggers a signal to a disconnect mechanism in the GFI, which cuts off the current in the faulty circuit.

  8. The internal propagation of fusion flame with the strong shock of a laser driven plasma block for advanced nuclear fuel ignition

    International Nuclear Information System (INIS)

    Malekynia, B.; Razavipour, S. S.

    2013-01-01

    An accelerated skin layer may be used to ignite solid state fuels. Detailed analyses were clarified by solving the hydrodynamic equations for nonlinear force driven plasma block ignition. In this paper, the complementary mechanisms are included for the advanced fuel ignition: external factors such as lasers, compression, shock waves, and sparks. The other category is created within the plasma fusion as reheating of an alpha particle, the Bremsstrahlung absorption, expansion, conduction, and shock waves generated by explosions. With the new condition for the control of shock waves, the spherical deuterium-tritium fuel density should be increased to 75 times that of the solid state. The threshold ignition energy flux density for advanced fuel ignition may be obtained using temperature equations, including the ones for the density profile obtained through the continuity equation and the expansion velocity for the r ≠ 0 layers. These thresholds are significantly reduced in comparison with the ignition thresholds at x = 0 for solid advanced fuels. The quantum correction for the collision frequency is applied in the case of the delay in ion heating. Under the shock wave condition, the spherical proton-boron and proton-lithium fuel densities should be increased to densities 120 and 180 times that of the solid state. These plasma compressions are achieved through a longer duration laser pulse or X-ray. (physics of gases, plasmas, and electric discharges)

  9. Technology for emission control in internal combustion engines; Kakushu nainen kikan ni okeru hai gas joka gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shioji, M. [Kyoto University, Kyoto (Japan)

    1998-09-01

    Described herein are emission control technology and exhaust gas cleaning measures for internal combustion engines. Gas turbines burn relatively high-quality fuels, such as natural gas, kerosene, diesel oil and gas oil, where the major concerns are to reduce NOx and dust emissions. The NOx abatement techniques fall into two general categories; wet processes which inject water or steam, and dry processes which depend on improved combustion. Power generation and cogeneration which burn natural gas adopt lean, premixed combustion and two-stage combustion as the major approaches. Low-speed, large-size diesel engines, which realize very high thermal efficiency, discharge high concentrations of NOx. Delayed fuel injection timing is the most easy NOx abatement technique to meet the related regulations, but is accompanied by decreased fuel economy. Use of water-emulsified fuel, water layer injection and multi-port injection can reduce NOx emissions without decreasing fuel economy, depending on optimization methods adopted. Automobile gasoline engines are required to further clean exhaust gases by catalystic systems. 9 refs., 10 figs., 6 tabs.

  10. Shock compression of synthetic opal

    International Nuclear Information System (INIS)

    Inoue, A; Okuno, M; Okudera, H; Mashimo, T; Omurzak, E; Katayama, S; Koyano, M

    2010-01-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO 4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO 2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  11. Shock compression of synthetic opal

    Science.gov (United States)

    Inoue, A.; Okuno, M.; Okudera, H.; Mashimo, T.; Omurzak, E.; Katayama, S.; Koyano, M.

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  12. Shock compression of synthetic opal

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, A; Okuno, M; Okudera, H [Department of Earth Sciences, Kanazawa University Kanazawa, Ishikawa, 920-1192 (Japan); Mashimo, T; Omurzak, E [Shock Wave and Condensed Matter Research Center, Kumamoto University, Kumamoto, 860-8555 (Japan); Katayama, S; Koyano, M, E-mail: okuno@kenroku.kanazawa-u.ac.j [JAIST, Nomi, Ishikawa, 923-1297 (Japan)

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO{sub 4} tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO{sub 2} glass. However, internal silanole groups still remain even at 38.1 GPa.

  13. Analysis of international and European policy instruments: pollution swapping . Task 2 Service contract "Integrated measures in agriculture to reduce ammonia emissions"

    NARCIS (Netherlands)

    Oenema, O.; Velthof, G.L.

    2007-01-01

    This Report describes the results of Task 2 ‘Analysis of International and European policy instruments’. The aim of this task is to analyze the existing International and European policy instruments aiming at reducing emissions of ammonia, nitrous oxide and methane to the atmosphere and nitrate to

  14. RCWA and FDTD modeling of light emission from internally structured OLEDs.

    Science.gov (United States)

    Callens, Michiel Koen; Marsman, Herman; Penninck, Lieven; Peeters, Patrick; de Groot, Harry; ter Meulen, Jan Matthijs; Neyts, Kristiaan

    2014-05-05

    We report on the fabrication and simulation of a green OLED with an Internal Light Extraction (ILE) layer. The optical behavior of these devices is simulated using both Rigorous Coupled Wave Analysis (RCWA) and Finite Difference Time-Domain (FDTD) methods. Results obtained using these two different techniques show excellent agreement and predict the experimental results with good precision. By verifying the validity of both simulation methods on the internal light extraction structure we pave the way to optimization of ILE layers using either of these methods.

  15. EU emission trading. Requirement of adaptation of the Cap as a consequence of external shocks and unexpected developments?; EU-Emissionshandel. Anpassungsbedarf des Caps als Reaktion auf externe Schocks und unerwartete Entwicklungen?

    Energy Technology Data Exchange (ETDEWEB)

    Diekmann, Jochen [DIW, Berlin (Germany)

    2012-11-15

    The effectivity of the European emission trading system (EU-ETS) with respect to the reduction of greenhouse gas emissions based essentially on the quantity of the emission caps. The regional, sectorial and temporal boundaries of this system as well as the regulations covering international flexible mechanisms and banking have to be considered in the evaluation of the effectivity of the EU-ETS. Under this aspect, the authors of the contribution under consideration discuss the advantages and disadvantages of the different variants of adjustment. First of all, the criteria for an identification of a possible justified needs of adaptation are investigated. Furthermore, the authors discuss the question about suitable points in time for an intervention.

  16. Greenhouse gas emission management in the US - current regional initiatives compared with international carbon trading programs

    International Nuclear Information System (INIS)

    Rink, A.G.; Law, S.

    2009-01-01

    In the United States (US) there are currently voluntary reporting programs (EPA Climate Leaders, Carbon Disclosure Project and The Climate Registry), organized market-based trading platforms (Chicago Climate Exchange and The Green Exchange) and proposed regional mandatory cap and trade programs in California, the Northeast, the West and the Midwest. The past success of the US Acid Rain 'cap-and-trade' system market-based format together with the availability of the European Union Emission Trading Scheme to serve as a template for future greenhouse gas regulations is promising as the US can participate in the world wide carbon markets already established. (author)

  17. Baselines for carbon emissions in the Indian and Chinese power sectors: Implications for international carbon trading

    International Nuclear Information System (INIS)

    Zhang Chi; Shukla, P.R.; Victor, David G.; Heller, Thomas C.; Biswas, Debashish; Nag, Tirthankar

    2006-01-01

    The study examines the dynamics of carbon emissions baselines of electricity generation in Indian states and Chinese provinces in the backdrop of ongoing electricity sector reforms in these countries. Two Indian states-Gujarat and Andhra Pradesh, and three Chinese provinces-Guangdong, Liaoning and Hubei have been chosen for detailed analysis to bring out regional variations that are not captured in aggregate country studies. The study finds that fuel mix is the main driver behind the trends exhibited by the carbon baselines in these five cases. The cases confirm that opportunities exist in the Indian and Chinese electricity sectors to lower carbon intensity mainly in the substitution of other fuels for coal and, to a lesser extent, adoption of more efficient and advanced coal-fired generation technology. Overall, the findings suggest that the electricity sectors in India and China are becoming friendlier to the global environment. Disaggregated analysis, detailed and careful industry analysis is essential to establishing a power sector carbon emissions baseline as a reference for CDM crediting. However, considering all the difficulties associated with the baseline issue, our case studies demonstrate that there is merit in examining alternate approaches that rely on more aggregated baselines

  18. The evolution of young HII regions. I. Continuum emission and internal dynamics

    Science.gov (United States)

    Klaassen, P. D.; Johnston, K. G.; Urquhart, J. S.; Mottram, J. C.; Peters, T.; Kuiper, R.; Beuther, H.; van der Tak, F. F. S.; Goddi, C.

    2018-04-01

    Context. High-mass stars form in much richer environments than those associated with isolated low-mass stars, and once they reach a certain mass, produce ionised (HII) regions. The formation of these pockets of ionised gas are unique to the formation of high-mass stars (M > 8 M⊙), and present an excellent opportunity to study the final stages of accretion, which could include accretion through the HII region itself. Aim. This study of the dynamics of the gas on both sides of these ionisation boundaries in very young HII regions aims to quantify the relationship between the HII regions and their immediate environments. Methods: We present high-resolution ( 0.5″) ALMA observations of nine HII regions selected from the red MSX source survey with compact radio emission and bolometric luminosities greater than 104 L⊙. We focus on the initial presentation of the data, including initial results from the radio recombination line H29α, some complementary molecules, and the 256 GHz continuum emission. Results: Of the six (out of nine) regions with H29α detections, two appear to have cometary morphologies with velocity gradients across them, and two appear more spherical with velocity gradients suggestive of infalling ionised gas. The remaining two were either observed at low resolution or had signals that were too weak to draw robust conclusions. We also present a description of the interactions between the ionised and molecular gas (as traced by CS (J = 5 - 4)), often (but not always) finding the HII region had cleared its immediate vicinity of molecules. Conclusions: Of our sample of nine, the observations of the two clusters expected to have the youngest HII regions (from previous radio observations) are suggestive of having infalling motions in the H29α emission, which could be indicative of late stage accretion onto the stars despite the presence of an HII region. Table A.2 is also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130

  19. International Experience with Key Program Elements of IndustrialEnergy Efficiency or Greenhouse Gas Emissions Reduction Target-SettingPrograms

    Energy Technology Data Exchange (ETDEWEB)

    Price, Lynn; Galitsky, Christina; Kramer, Klaas Jan

    2008-02-02

    Target-setting agreements, also known as voluntary ornegotiated agreements, have been used by a number of governments as amechanism for promoting energy efficiency within the industrial sector. Arecent survey of such target-setting agreement programs identified 23energy efficiency or GHG emissions reduction voluntary agreement programsin 18 countries. International best practice related to target-settingagreement programs calls for establishment of a coordinated set ofpolicies that provide strong economic incentives as well as technical andfinancial support to participating industries. The key program elementsof a target-setting program are the target-setting process,identification of energy-saving technologies and measures usingenergy-energy efficiency guidebooks and benchmarking as well as byconducting energy-efficiency audits, development of an energy-savingsaction plan, development and implementation of energy managementprotocols, development of incentives and supporting policies, monitoringprogress toward targets, and program evaluation. This report firstprovides a description of three key target-setting agreement programs andthen describes international experience with the key program elementsthat comprise such programs using information from the three keytarget-setting programs as well as from other international programsrelated to industrial energy efficiency or GHG emissionsreductions.

  20. The relationships between termite mound CH4/CO2 emissions and internal concentration ratios are species specific

    Directory of Open Access Journals (Sweden)

    H. Jamali

    2013-04-01

    Full Text Available We investigated the relative importance of CH4 and CO2 fluxes from soil and termite mounds at four different sites in the tropical savannas of northern Australia near Darwin and assessed different methods to indirectly predict CH4 fluxes based on CO2 fluxes and internal gas concentrations. The annual flux from termite mounds and surrounding soil was dominated by CO2 with large variations among sites. On a carbon dioxide equivalent (CO2-e basis, annual CH4 flux estimates from termite mounds were 5- to 46-fold smaller than the concurrent annual CO2 flux estimates. Differences between annual soil CO2 and soil CH4 (CO2-e fluxes were even greater, soil CO2 fluxes being almost three orders of magnitude greater than soil CH4 (CO2-e fluxes at site. The contribution of CH4 and CO2 emissions from termite mounds to the total CH4 and CO2 emissions from termite mounds and soil in CO2-e was less than 1%. There were significant relationships between mound CH4 flux and mound CO2 flux, enabling the prediction of CH4 flux from measured CO2 flux; however, these relationships were clearly termite species specific. We also observed significant relationships between mound flux and gas concentration inside mound, for both CH4 and CO2, and for all termite species, thereby enabling the prediction of flux from measured mound internal gas concentration. However, these relationships were also termite species specific. Using the relationship between mound internal gas concentration and flux from one species to predict mound fluxes from other termite species (as has been done in the past would result in errors of more than 5-fold for mound CH4 flux and 3-fold for mound CO2 flux. This study highlights that CO2 fluxes from termite mounds are generally more than one order of magnitude greater than CH4 fluxes. There are species-specific relationships between CH4 and CO2 fluxes from a mound, and between the inside mound concentration of a gas and the mound flux emission of the

  1. The relationships between termite mound CH4/CO2 emissions and internal concentration ratios are species specific

    Science.gov (United States)

    Jamali, H.; Livesley, S. J.; Hutley, L. B.; Fest, B.; Arndt, S. K.

    2013-04-01

    We investigated the relative importance of CH4 and CO2 fluxes from soil and termite mounds at four different sites in the tropical savannas of northern Australia near Darwin and assessed different methods to indirectly predict CH4 fluxes based on CO2 fluxes and internal gas concentrations. The annual flux from termite mounds and surrounding soil was dominated by CO2 with large variations among sites. On a carbon dioxide equivalent (CO2-e) basis, annual CH4 flux estimates from termite mounds were 5- to 46-fold smaller than the concurrent annual CO2 flux estimates. Differences between annual soil CO2 and soil CH4 (CO2-e) fluxes were even greater, soil CO2 fluxes being almost three orders of magnitude greater than soil CH4 (CO2-e) fluxes at site. The contribution of CH4 and CO2 emissions from termite mounds to the total CH4 and CO2 emissions from termite mounds and soil in CO2-e was less than 1%. There were significant relationships between mound CH4 flux and mound CO2 flux, enabling the prediction of CH4 flux from measured CO2 flux; however, these relationships were clearly termite species specific. We also observed significant relationships between mound flux and gas concentration inside mound, for both CH4 and CO2, and for all termite species, thereby enabling the prediction of flux from measured mound internal gas concentration. However, these relationships were also termite species specific. Using the relationship between mound internal gas concentration and flux from one species to predict mound fluxes from other termite species (as has been done in the past) would result in errors of more than 5-fold for mound CH4 flux and 3-fold for mound CO2 flux. This study highlights that CO2 fluxes from termite mounds are generally more than one order of magnitude greater than CH4 fluxes. There are species-specific relationships between CH4 and CO2 fluxes from a mound, and between the inside mound concentration of a gas and the mound flux emission of the same gas, but

  2. Emissions Trading

    NARCIS (Netherlands)

    Woerdman, Edwin; Backhaus, Juergen

    2014-01-01

    Emissions trading is a market-based instrument to achieve environmental targets in a cost-effective way by allowing legal entities to buy and sell emission rights. The current international dissemination and intended linking of emissions trading schemes underlines the growing relevance of this

  3. Collisionless electrostatic shocks

    DEFF Research Database (Denmark)

    Andersen, H.K.; Andersen, S.A.; Jensen, Vagn Orla

    1970-01-01

    An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth......An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth...

  4. Shocking revelations

    International Nuclear Information System (INIS)

    Crum, L.A.; Matula, T.J.

    1997-01-01

    In single-bubble sonoluminescence (SBSL) a small gas bubble that has been acoustically levitated in a liquid driven into large amplitude volume oscillations by the sound fields, radiation visible light each and every acoustic cycle. These emissions could potentially lead to thermonuclear fusion. This paper reports on the background of SBSL, what the current research is, and what questions need to be answered in the future. 26 refs., 1 fig

  5. Equipment to reduce the emission of noxious components in the exhaust gas of an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Tatsutomi, Y; Inoue, H

    1976-10-21

    The invention concerns an arrangement for the reduction of emission of noxious components in exhaust gas of an internal combustion engine with automatic drive. According to the invention, there is a further switch in parallel with the usual kickdown switch, which is actuated by a temperature sensor and/or choke. If the operating temperature of the engine is below a certain value, or if the choke is pulled out, then the switch is closed. This has the effect that the downstream valve is brought into the same position as that in which the closed kickdown switch would place it. The automatic drive therefore takes up that position, independently of the position of the accelerator pedal, which it would normally occupy only with the accelerator pedal fully pressed down. This guarantees that the engine is always kept at high speed during the hot running phase, which reduces the portion of the noxious gas components emitted.

  6. Reducing energy consumption and CO2 emissions by energy efficiency measures and international trading: A bottom-up modeling for the U.S. iron and steel sector

    International Nuclear Information System (INIS)

    Karali, Nihan; Xu, Tengfang; Sathaye, Jayant

    2014-01-01

    Highlights: • Use ISEEM to evaluate energy and emission reduction in U.S. Iron and Steel sector. • ISEEM is a new bottom-up optimization model for industry sector energy planning. • Energy and emission reduction includes efficiency measure and international trading. • International trading includes commodity and carbon among U.S., China and India. • Project annual energy use, CO 2 emissions, production, and costs from 2010 to 2050. - Abstract: Using the ISEEM modeling framework, we analyzed the roles of energy efficiency measures, steel commodity and international carbon trading in achieving specific CO 2 emission reduction targets in the U.S iron and steel sector from 2010 to 2050. We modeled how steel demand is balanced under three alternative emission reduction scenarios designed to include national energy efficiency measures, commodity trading, and international carbon trading as key instruments to meet a particular emission restriction target in the U.S. iron and steel sector; and how production, process structure, energy supply, and system costs change with those scenarios. The results advance our understanding of long-term impacts of different energy policy options designed to reduce energy consumption and CO 2 emissions for U.S. iron and steel sector, and generate insight of policy implications for the sector’s environmentally and economically sustainable development. The alternative scenarios associated with 20% emission-reduction target are projected to result in approximately 11–19% annual energy reduction in the medium term (i.e., 2030) and 9–20% annual energy reduction in the long term (i.e., 2050) compared to the Base scenario

  7. PRECURSORS TO INTERSTELLAR SHOCKS OF SOLAR ORIGIN

    Energy Technology Data Exchange (ETDEWEB)

    Gurnett, D. A.; Kurth, W. S. [University of Iowa, Department of Physics and Astronomy, Iowa City, IA 52242 (United States); Stone, E. C.; Cummings, A. C. [California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Krimigis, S. M.; Decker, R. B. [Applied Physics Laboratory/JHU, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Ness, N. F. [Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064 (United States); Burlaga, L. F., E-mail: donald-gurnett@uiowa.edu [NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States)

    2015-08-20

    On or about 2012 August 25, the Voyager 1 spacecraft crossed the heliopause into the nearby interstellar plasma. In the nearly three years that the spacecraft has been in interstellar space, three notable particle and field disturbances have been observed, each apparently associated with a shock wave propagating outward from the Sun. Here, we present a detailed analysis of the third and most impressive of these disturbances, with brief comparisons to the two previous events, both of which have been previously reported. The shock responsible for the third event was first detected on 2014 February 17 by the onset of narrowband radio emissions from the approaching shock, followed on 2014 May 13 by the abrupt appearance of intense electron plasma oscillations generated by electrons streaming outward ahead of the shock. Finally, the shock arrived on 2014 August 25, as indicated by a jump in the magnetic field strength and the plasma density. Various disturbances in the intensity and anisotropy of galactic cosmic rays were also observed ahead of the shock, some of which are believed to be caused by the reflection and acceleration of cosmic rays by the magnetic field jump at the shock, and/or by interactions with upstream plasma waves. Comparisons to the two previous weaker events show somewhat similar precursor effects, although differing in certain details. Many of these effects are very similar to those observed in the region called the “foreshock” that occurs upstream of planetary bow shocks, only on a vastly larger spatial scale.

  8. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    KAUST Repository

    Mostert, W.; Pullin, D. I.; Samtaney, Ravi; Wheatley, V.

    2016-01-01

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  9. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    KAUST Repository

    Mostert, W.

    2016-12-12

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  10. Proceedings of the International Symposium on Shock Tubes and Waves (12th) Held at Jerusalem on 16-19 July 1979.

    Science.gov (United States)

    1980-02-01

    Jets (Research and Development) Ltd., Rept. No. 2202/x 41 (1955). 7. Peter K. Doerfler, "Comprex Supercharging of Vehicle Diesel 5igic," Soc. of...LL CONTOUR . Zec x6106 -0.4 - SHOCKTUE: Ne *SHOCK UBE: 6 Re - 2 x 10 D .-- RI3 T -0.2 WALL TEST SECTION 0 No 8 - .83 \\ 0.2 0.4 0.6 0.8 1. \\0.84~/c 6...FLAT-PLATE BOUNDARY-LAYER FLOWS IN IONIZING ARGON IRVINE ISRAEL GLASS. WILLIAM SHIUN Liu*, KAZuVOSHI TAKAYAMA** and PETER IRVING BRIMELnWwt Institute

  11. Emission behavior of OH radical in internal EGR using a 2-cycle engine; 2 cycle engine wo mochiita naibu EGR no OH radical no hakko kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, S; Amino, Y; Yoshida, K; Shoji, H; Saima, A [Nihon University, Tokyo (Japan)

    1997-10-01

    The purpose of this study was to examine and consider the influence, which the remained gas exercised on combustion. 2-cycle engine was Used as the test engine. Internal EGR was run. The means was that the test engine was fitted the back pressure control plate on the exhaust port. The conditions, which were run with internal EGR and without internal EGR, were compared. The OH radical, which plays important role in combustion of hydrocarbon fuels, was measured with emission spectroscopy. In internal EGR, the unburned end gas on exhaust port side was susceptible to the remained gas. 6 refs., 8 figs., 1 tab.

  12. Radiative shocks with electron thermal conduction

    International Nuclear Information System (INIS)

    Borkowski, Kazimierz.

    1988-01-01

    The authors studies the influence of electron thermal conduction on radiative shock structure for both one- and two-temperature plasmas. The dimensionless ratio of the conductive length to the cooling length determines whether or not conduction is important, and shock jump conditions with conduction are established for a collisionless shock front. He obtains approximate solutions with the assumptions that the ionization state of the gas is constant and the cooling rate is a function of temperature alone. In the absence of magnetic fields, these solutions indicate that conduction noticeably influences normal-abundance interstellar shocks with velocities 50-100 km s -1 and dramatically affects metal-dominated shocks over a wide range of shock velocities. Magnetic fields inhibit conduction, but the conductive energy flux and the corresponding decrease in the post-shock electron temperature may still be appreciable. He calculates detailed steady-state radiative shock models in gas composed entirely of oxygen, with the purpose of explaining observations of fast-moving knots in Cas A and other oxygen-rich supernova remnants (SNRs). The O III ion, whose forbidden emission usually dominates the observed spectra, is present over a wide range of shock velocities, from 100 to 170 kms -1 . All models with conduction have extensive warm photoionization zones, which provides better agreement with observed optical (O I) line strengths. However, the temperatures in these zones could be lowered by (Si II) 34.8 μm and (Ne II) 12.8 μm cooling if Si and Ne are present in appreciable abundance relative to O. Such low temperatures would be inconsistent with the observed (O I) emission in oxygen-rich SNRs

  13. Acting Globally: Potential Carbon Emissions Mitigation Impacts from an International Standards and Labelling Program

    Energy Technology Data Exchange (ETDEWEB)

    McNeil, Michael A; Letschert, Virginie E.; de la Rue du Can, Stephane; Egan, Christine

    2009-05-29

    This paper presents an analysis of the potential impacts of an international initiative designed to support and promote the development and implementation of appliances standards and labelling programs throughout the world. As part of previous research efforts, LBNL developed the Bottom Up Energy Analysis System (BUENAS), an analysis framework that estimates impact potentials of energy efficiency policies on a global scale. In this paper, we apply this framework to an initiative that would result in the successful implementation of programs focused on high priority regions and product types, thus evaluating the potential impacts of such an initiative in terms of electricity savings and carbon mitigation in 2030. In order to model the likely parameters of such a program, we limit impacts to a five year period starting in 2009, but assume that the first 5 years of a program will result in implementation of 'best practice' minimum efficiency performance standards by 2014. The 'high priority' regions considered are: Brazil, China, the European Union,India, Mexico and the United States. The products considered are: refrigerators, air conditioners, lighting (both fluorescent and incandescent), standby power (for consumer electronics) and televisions in the residential sector, and air conditioning and lighting in commercial buildings. In 2020, these regions and enduses account for about 37percent of global residential electricity and 29percent of electricity in commercial buildings. We find that 850Mt of CO2 could be saved in buildings by 2030 compared to the baseline forecast.

  14. A Prognostic Model for Development of Profound Shock among Children Presenting with Dengue Shock Syndrome.

    Directory of Open Access Journals (Sweden)

    Phung Khanh Lam

    Full Text Available To identify risk factors and develop a prediction model for the development of profound and recurrent shock amongst children presenting with dengue shock syndrome (DSS.We analyzed data from a prospective cohort of children with DSS recruited at the Paediatric Intensive Care Unit of the Hospital for Tropical Disease in Ho Chi Minh City, Vietnam. The primary endpoint was "profound DSS", defined as ≥2 recurrent shock episodes (for subjects presenting in compensated shock, or ≥1 recurrent shock episodes (for subjects presenting initially with decompensated/hypotensive shock, and/or requirement for inotropic support. Recurrent shock was evaluated as a secondary endpoint. Risk factors were pre-defined clinical and laboratory variables collected at the time of presentation with shock. Prognostic model development was based on logistic regression and compared to several alternative approaches.The analysis population included 1207 children of whom 222 (18% progressed to "profound DSS" and 433 (36% had recurrent shock. Independent risk factors for both endpoints included younger age, earlier presentation, higher pulse rate, higher temperature, higher haematocrit and, for females, worse hemodynamic status at presentation. The final prognostic model for "profound DSS" showed acceptable discrimination (AUC=0.69 for internal validation and calibration and is presented as a simple score-chart.Several risk factors for development of profound or recurrent shock among children presenting with DSS were identified. The score-chart derived from the prognostic models should improve triage and management of children presenting with DSS in dengue-endemic areas.

  15. Grain Destruction in a Supernova Remnant Shock Wave

    Science.gov (United States)

    Raymond, John C.; Ghavamian, Parviz; Williams, Brian J.; Blair, William P.; Borkowski, Kazimierz J.; Gaetz, Terrance J.; Sankrit, Ravi

    2014-01-01

    Dust grains are sputtered away in the hot gas behind shock fronts in supernova remnants, gradually enriching the gas phase with refractory elements. We have measured emission in C IV (lambda)1550 from C atoms sputtered from dust in the gas behind a non-radiative shock wave in the northern Cygnus Loop. Overall, the intensity observed behind the shock agrees approximately with predictions from model calculations that match the Spitzer 24 micron and the X-ray intensity profiles. Thus these observations confirm the overall picture of dust destruction in SNR shocks and the sputtering rates used in models. However, there is a discrepancy in that the CIV intensity 10'' behind the shock is too high compared to the intensities at the shock and 25'' behind it. Variations in the density, hydrogen neutral fraction and the dust properties over parsec scales in the pre- shock medium limit our ability to test dust destruction models in detail.

  16. Impact of Shock Front Rippling and Self-reformation on the Electron Dynamics at Low-Mach-number Shocks

    Science.gov (United States)

    Yang, Zhongwei; Lu, Quanming; Liu, Ying D.; Wang, Rui

    2018-04-01

    Electron dynamics at low-Mach-number collisionless shocks are investigated by using two-dimensional electromagnetic particle-in-cell simulations with various shock normal angles. We found: (1) The reflected ions and incident electrons at the shock front provide an effective mechanism for the quasi-electrostatic wave generation due to the charge-separation. A fraction of incident electrons can be effectively trapped and accelerated at the leading edge of the shock foot. (2) At quasi-perpendicular shocks, the electron trapping and reflection is nonuniform due to the shock rippling along the shock surface and is more likely to take place at some locations accompanied by intense reflected ion-beams. The electron trapping process has a periodical evolution over time due to the shock front self-reformation, which is controlled by ion dynamics. Thus, this is a cross-scale coupling phenomenon. (3) At quasi-parallel shocks, reflected ions can travel far back upstream. Consequently, quasi-electrostatic waves can be excited in the shock transition and the foreshock region. The electron trajectory analysis shows these waves can trap electrons at the foot region and reflect a fraction of them far back upstream. Simulation runs in this paper indicate that the micro-turbulence at the shock foot can provide a possible scenario for producing the reflected electron beam, which is a basic condition for the type II radio burst emission at low-Mach-number interplanetary shocks driven by Coronal Mass Ejections (CMEs).

  17. Radiography for a Shock-accelerated Liquid Layer

    International Nuclear Information System (INIS)

    P. Meekunnasombat J.G. Oakley/inst M.H. Anderson R. Bonazza

    2005-01-01

    This program supported the experimental study of the interaction of planar shock waves with both solid structures (a single cylinder or a bank of cylinders) and single and multiple liquid layers. Objectives of the study included: characterization of the shock refraction patterns; measurements of the impulsive loading of the solid structures; observation of the response of the liquid layers to shock acceleration; assessment of the shock-mitigation effects of single and multiple liquid layers. The uploaded paper is intended as a final report for the entire funding period. The poster described in the paper won the Best Poster Award at the 25 International Symposium on Shock Waves

  18. Energy input and response from prompt and early optical afterglow emission in gamma-ray bursts.

    Science.gov (United States)

    Vestrand, W T; Wren, J A; Wozniak, P R; Aptekar, R; Golentskii, S; Pal'shin, V; Sakamoto, T; White, R R; Evans, S; Casperson, D; Fenimore, E

    2006-07-13

    The taxonomy of optical emission detected during the critical first few minutes after the onset of a gamma-ray burst (GRB) defines two broad classes: prompt optical emission correlated with prompt gamma-ray emission, and early optical afterglow emission uncorrelated with the gamma-ray emission. The standard theoretical interpretation attributes prompt emission to internal shocks in the ultra-relativistic outflow generated by the internal engine; early afterglow emission is attributed to shocks generated by interaction with the surrounding medium. Here we report on observations of a bright GRB that, for the first time, clearly show the temporal relationship and relative strength of the two optical components. The observations indicate that early afterglow emission can be understood as reverberation of the energy input measured by prompt emission. Measurements of the early afterglow reverberations therefore probe the structure of the environment around the burst, whereas the subsequent response to late-time impulsive energy releases reveals how earlier flaring episodes have altered the jet and environment parameters. Many GRBs are generated by the death of massive stars that were born and died before the Universe was ten per cent of its current age, so GRB afterglow reverberations provide clues about the environments around some of the first stars.

  19. International trade and Austria's livestock system: Direct and hidden carbon emission flows associated with production and consumption of products

    International Nuclear Information System (INIS)

    Gavrilova, Olga; Jonas, Matthias; Erb, Karlheinz; Haberl, Helmut

    2010-01-01

    The Kyoto Protocol created a framework of responsibilities and mechanisms to mitigate climate change by reducing the emissions of greenhouse gases (GHGs) into the atmosphere. The Protocol stipulates accounting and reporting of GHG emissions and removals, such as energy use, industrial processes, agriculture, waste and net emissions resulting from land use, land-use change and forestry (LULUCF) activities. Emissions reported according to the rules set by the Kyoto Protocol do not include GHG emissions outside a country's boundaries resulting from the production of imported goods or services. As a result, GHG accounts constructed according to the Kyoto Protocol reflect the GHG emissions resulting from the production system of a country, but not all the emissions resulting from the consumption of goods and services within the country. However, as previous studies demonstrate, a country's emission balance changes remarkably if emissions related to goods or services imported and exported are taken into account. Here, we go beyond the aforementioned studies which mainly focus on GHG emissions from fossil fuel combustion. We assess, in a first-order approach, upstream emissions that result from LULUC activities outside a country while the produced goods are consumed within the country. In our study we focus on Austria's livestock system to elucidate the difference between production and consumption-related emissions accounting approaches. We study direct and 'hidden' (embodied) GHG emissions associated with Austria's bilateral trade in livestock and livestock-related products, based on the integration of full carbon accounting (FCA) and life cycle analysis (LCA). (author)

  20. Are Credit Shocks Supply or Demand Shocks?

    OpenAIRE

    Bijapur, Mohan

    2013-01-01

    This paper provides new insights into the relationship between the supply of credit and the macroeconomy. We present evidence that credit shocks constitute shocks to aggregate supply in that they have a permanent effect on output and cause inflation to rise in the short term. Our results also suggest that the effects on aggregate supply have grown stronger in recent decades.

  1. Extremely Bright GRB 160625B with Multiple Emission Episodes: Evidence for Long-term Ejecta Evolution

    Energy Technology Data Exchange (ETDEWEB)

    Lü, Hou-Jun; Lü, Jing; Zhong, Shu-Qing; Huang, Xiao-Li; Zhang, Hai-Ming; Lan, Lin; Lu, Rui-Jing; Liang, En-Wei [Guangxi Key Laboratory for Relativistic Astrophysics, Department of Physics, Guangxi University, Nanning 530004 (China); Xie, Wei, E-mail: lhj@gxu.edu.edu, E-mail: lew@gxu.edu.cn [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2017-11-01

    GRB 160625B is an extremely bright GRB with three distinct emission episodes. By analyzing its data observed with the Gamma-Ray Burst Monitor (GBM) and Large Area Telescope (LAT) on board the Fermi mission, we find that a multicolor blackbody (mBB) model can be used to fit very well the spectra of the initial short episode (Episode I) within the hypothesis of photosphere emission of a fireball model. The time-resolved spectra of its main episode (Episode II), which was detected with both GBM and LAT after a long quiescent stage (∼180 s) following the initial episode, can be fitted with a model comprising an mBB component plus a cutoff power-law (CPL) component. This GRB was detected again in the GBM and LAT bands with a long extended emission (Episode III) after a quiescent period of ∼300 s. The spectrum of Episode III is adequately fitted with CPL plus single power-law models, and no mBB component is required. These features may imply that the emission of the three episodes are dominated by distinct physics processes, i.e., Episode I is possible from the cocoon emission surrounding the relativistic jet, Episode II may be from photosphere emission and internal shock of the relativistic jet, and Episode III is contributed by internal and external shocks of the relativistic jet. On the other hand, both X-ray and optical afterglows are consistent with the standard external shocks model.

  2. Shock absorbing structure

    International Nuclear Information System (INIS)

    Kojima, Naoki; Matsushita, Kazuo.

    1992-01-01

    Small pieces of shock absorbers are filled in a space of a shock absorbing vessel which is divided into a plurality of sections by partitioning members. These sections function to prevent excess deformation or replacement of the fillers upon occurrence of falling accident. Since the shock absorbing small pieces in the shock absorbing vessel are filled irregularly, shock absorbing characteristics such as compression strength is not varied depending on the direction, but they exhibit excellent shock absorbing performance. They surely absorb shocks exerted on a transportation vessel upon falling or the like. If existing artificial fillers such as pole rings made of metal or ceramic and cut pieces such as alumium extrusion molding products are used as the shock absorbing pieces, they have excellent fire-proofness and cold resistance since the small pieces are inflammable and do not contain water. (T.M.)

  3. Melting under shock compression

    International Nuclear Information System (INIS)

    Bennett, B.I.

    1980-10-01

    A simple model, using experimentally measured shock and particle velocities, is applied to the Lindemann melting formula to predict the density, temperature, and pressure at which a material will melt when shocked from room temperature and zero pressure initial conditions

  4. Condensed matter at high shock pressures

    Energy Technology Data Exchange (ETDEWEB)

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-07-12

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N/sub 2/, CO, SiO/sub 2/-aerogel, H/sub 2/O, and C/sub 6/H/sub 6/. The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab.

  5. Converging shocks in elastic-plastic solids.

    Science.gov (United States)

    Ortega, A López; Lombardini, M; Hill, D J

    2011-11-01

    We present an approximate description of the behavior of an elastic-plastic material processed by a cylindrically or spherically symmetric converging shock, following Whitham's shock dynamics theory. Originally applied with success to various gas dynamics problems, this theory is presently derived for solid media, in both elastic and plastic regimes. The exact solutions of the shock dynamics equations obtained reproduce well the results obtained by high-resolution numerical simulations. The examined constitutive laws share a compressible neo-Hookean structure for the internal energy e=e(s)(I(1))+e(h)(ρ,ς), where e(s) accounts for shear through the first invariant of the Cauchy-Green tensor, and e(h) represents the hydrostatic contribution as a function of the density ρ and entropy ς. In the strong-shock limit, reached as the shock approaches the axis or origin r=0, we show that compression effects are dominant over shear deformations. For an isothermal constitutive law, i.e., e(h)=e(h)(ρ), with a power-law dependence e(h) is proportional to ρ(α), shock dynamics predicts that for a converging shock located at r=R(t) at time t, the Mach number increases as M is proportional to [log(1/R)](α), independently of the space index s, where s=2 in cylindrical geometry and 3 in spherical geometry. An alternative isothermal constitutive law with p(ρ) of the arctanh type, which enforces a finite density in the strong-shock limit, leads to M is proportional to R(-(s-1)) for strong shocks. A nonisothermal constitutive law, whose hydrostatic part e(h) is that of an ideal gas, is also tested, recovering the strong-shock limit M is proportional to R(-(s-1)/n(γ)) originally derived by Whitham for perfect gases, where γ is inherently related to the maximum compression ratio that the material can reach, (γ+1)/(γ-1). From these strong-shock limits, we also estimate analytically the density, radial velocity, pressure, and sound speed immediately behind the shock. While the

  6. Biomass shock pretreatment

    Science.gov (United States)

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  7. Measurement of cerebral blood flow by single photon emission computed tomography in cases of internal carotid artery occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Sunada, Ichiro [Osaka City Univ. (Japan). Faculty of Medicine

    1989-06-01

    Cerebral blood flow (CBF) was measured with {sup 133}xenon inhalation and single photon emission computed tomography in 33 cases of internal carotid artery occlusion, in the resting state and 25 minutes after acetazolamide administration. The patient population consisted of 24 males and nine females with a mean age of 57 years, who presented with transient ischemic attacks or stroke. Acetazolamide inhibits carbonic anhydrase, and CBF increases as a result of dilatation of cerebral arteries due to CO{sub 2} accumulation. The mean CBF was 46 ml/100 g/min on the affected hemisphere and 56 ml/100 g/min on the unaffected hemisphere. The mean CBF value obtained by the same method in 10 normal volunteers was 55 ml/100 g/min. The average increase in CBF after acetazolamide administration was 9% on the affected side and 17% on the unaffected side. The average increase in 10 normal volunteers was 32%. The reduced cerebral arterial reactivity to acetazolamide administration was bilateral in the patient group, suggesting that the cerebral arteries were dilated so as to maintain normal CBF. Extra-intracranial (EC-IC) bypass surgery was performed in nine patients. Preoperatively, the mean CBF was 48 ml/100 g/min on the affected side and 57 ml/100 g/min on the unaffected side. With postoperative acetazolamide administration, the percent increase in CBF rose from 13% to 22% on the affected side and from 17% to 23% on the unaffected side. The bilateral change toward normal in cerebral arterial reactivity to acetazolamide indicates that the dilated cerebral arteries returned to normal after EC-IC bypass surgery. This suggests that bypass surgery is effective in patients with internal carotid artery occlusion in whom ischemia is caused only by hemodynamic factors, and that measurement of CBF via acetazolamide loading is useful in identifying appropriate candidates for bypass surgery.

  8. Research to assess impacts on developing countries of measures to address emissions in the international aviation and shipping sectors

    Energy Technology Data Exchange (ETDEWEB)

    Anger, A. [Cambridge University, Cambridge (United Kingdom); Faber, J.; Koopman, M. [CE Delft, Delft (Netherlands); Van Velzen, A. [Transport Analysis and Knowledge Systems TAKS, s.l. (Netherlands); Long, K.; Pollitt, H.; Barker, T. [Cambridge Econometrics, Cambridge (United Kingdom); Comberti, C.; Fazekas, D.; Blachowicz, A. [Climate Strategies, London (United Kingdom)

    2013-02-15

    The greenhouse gas emissions of international aviation and maritime transport are projected to increase rapidly over the coming decades, despite significant improvements in the fuel efficiency of aircraft and ships. In order to address their growth, Market Based Measures (MBMs) have been proposed to complement technical and operational measures. These measures are being discussed in ICAO (the UN organization for civil aviation) and IMO (the UN organization for maritime transport). One of the main issues in the debate has been the impact of MBMs on developing countries and especially on remote economies. This report quantifies the economic impacts of MBMs on ten case study economies and globally. The case study economies have been selected in the expectation that they would be relatively highly impacted because of their remoteness and/or dependence on international aviation or maritime transport. This report shows that the decrease in GDP is less than 0.01% on average and significantly less than 0.1% for all but a few of the case study countries. Countries with a higher dependency on tourism and trade are likely to experience greater economic impacts as market-based measures raise the costs of aviation and maritime transport; they impact economies due to increased prices for passenger travel and exported and imported goods. Some of these countries are small island states that are also vulnerable to climate change impacts. Undesired economic impacts on developing countries can be addressed effectively by a combination of measures such as exemptions of certain routes, lump sum rebates, and investments in infrastructure efficiency and development of more efficient ships and aircraft.

  9. An investigation of the techno-economic impact of internal combustion engine based cogeneration systems on the energy requirements and greenhouse gas emissions of the Canadian housing stock

    International Nuclear Information System (INIS)

    Asaee, S. Rasoul; Ugursal, V. Ismet; Beausoleil-Morrison, Ian

    2015-01-01

    This study provides a techno-economic evaluation of retrofitting internal combustion engine (ICE) based cogeneration systems in the Canadian housing stock (CHS). The study was conducted using the Canadian Hybrid Residential End-Use Energy and GHG Emissions Model (CHREM). CHREM includes close to 17,000 unique house files that are statistically representative of the Canadian housing stock. The cogeneration system performance was evaluated using a high resolution integrated building performance simulation software. It is assumed that the ICE cogeneration system is retrofitted into all houses that currently use a central space heating system and have a suitable basement or crawl space. The GHG emission intensity factor associated with marginal electricity generation in each province is used to estimate the annual GHG emissions reduction due to the cogeneration system retrofit. The results show that cogeneration retrofit yields 13% energy savings in the CHS. While the annual GHG emissions would increase in some provinces due to cogeneration retrofits, the total GHG emissions of the CHS would be reduced by 35%. The economic analysis indicates that ICE cogeneration system retrofits may provide an economically feasible opportunity to approach net/nearly zero energy status for existing Canadian houses. - Highlights: • Techno-economic evaluation ICE cogeneration systems for Canadian housing is reported. • ICE cogeneration retrofit could yield 13% annual energy savings in Canadian housing. • Annual GHG emissions of Canadian housing could decrease by 35% with ICE cogeneration. • But, in some provinces, GHG emissions would increase as a result of ICE cogeneration

  10. Relativistic Shock Acceleration

    International Nuclear Information System (INIS)

    Duffy, P.; Downes, T.P.; Gallant, Y.A.; Kirk, J.G.

    1999-01-01

    In this paper we briefly review the basic theory of shock waves in relativistic hydrodynamics and magneto-hydrodynamics, emphasising some astrophysically interesting cases. We then present an overview of the theory of particle acceleration at such shocks describing the methods used to calculate the spectral indices of energetic particles. Recent results on acceleration at ultra-relativistic shocks are discussed. (author)

  11. PIXE in 1980: Summary of the second international conference on particle induced x-ray emission and its analytical applications

    International Nuclear Information System (INIS)

    Akselsson, K.R.

    1981-01-01

    The Second International Conference on Particle Induced X-ray Emission (PIXE) and its analytical applications was held in Lund, Sweden, June 9-12, 1980. About a hundred papers were presented, including seven invited talks (PIXE and particle scattering, microbeam analysis, applications to aerosols and biological samples). The main impression left by the conference was that both the PIXE method and its applications are in a phase of fast development. Considerable effort has successfully been devoted to optimizing the basic PIXE technique. Also the great advantage of simultaneously getting information about lighter elements and sample mass was reported to have been successfully employed in routine analyses. PIXE, which was initially considered to be a method mainly for thin samples, has also been shown to be competitive for a variety of thick samples. Data from aerosol studies was presented. With the PIXE-method, it is feasible to perform series of measurements over a long period of time, many samples in parallel and/or samples from sites of poor accessibility. However, the advantages of PIXE may be further exploited in aerosol investigations and some promising lines of sampler development were reported. Sample preparation techniques are crucial for applications to biological samples and several laboratories are engaged in such developmental work. However, it was also evident that PIXE is already giving significant contributions to research in biology and medicine

  12. Modeling of secondary emission processes in the negative ion based electrostatic accelerator of the International Thermonuclear Experimental Reactor

    Directory of Open Access Journals (Sweden)

    G. Fubiani

    2008-01-01

    Full Text Available The negative ion electrostatic accelerator for the neutral beam injector of the International Thermonuclear Experimental Reactor (ITER is designed to deliver a negative deuterium current of 40 A at 1 MeV. Inside the accelerator there are several types of interactions that may create secondary particles. The dominating process originates from the single and double stripping of the accelerated negative ion by collision with the residual molecular deuterium gas (≃29% losses. The resulting secondary particles (positive ions, neutrals, and electrons are accelerated and deflected by the electric and magnetic fields inside the accelerator and may induce more secondaries after a likely impact with the accelerator grids. This chain of reactions is responsible for a non-negligible heat load on the grids and must be understood in detail. In this paper, we will provide a comprehensive summary of the physics involved in the process of secondary emission in a typical ITER-like negative ion electrostatic accelerator together with a precise description of the numerical method and approximations involved. As an example, the multiaperture-multigrid accelerator concept will be discussed.

  13. International IPCC workshop on methane and nitrous oxide: methods in national emissions inventories and options for control

    Energy Technology Data Exchange (ETDEWEB)

    Amstel, A.R. van (ed.)

    1993-07-01

    This workshop had two main objectives: to support the development of an internationally agreed methodology and reporting format for national emission inventories of greenhouse gases by mid 1993, as coordinated by the Science Working Group of the Intergovernmental Panel on Climate Change (IPCC) and the Organization for Economic Cooperation and Development (OECD); and the development of technical options for reduction of these greenhouse gases and the assessment of the socio-economic feasibility of these options. These proceedings contain the overview papers presented at the workshop, the background papers prepared for the working group sessions and the conclusions and recommendations of the working groups put forward during these sessions. 16 poster summaries are also included. During the workshop, 8 different sources of methane were discussed - oil and gas, coal mining, ruminants, animal waste, landfills and sewage treatments, combustion and industry, rice production and wetlands, and biomass burning - and 2 sources of nitrous oxide - agricultural soils and combustion and industry. All papers have been abstracted separately.

  14. THE NEWLY BORN MAGNETARS POWERING GAMMA-RAY BURST INTERNAL-PLATEAU EMISSION: ARE THERE STRANGE STARS?

    International Nuclear Information System (INIS)

    Yu Yunwei; Cao Xiaofeng; Zheng Xiaoping

    2009-01-01

    The internal-plateau X-ray emission of gamma-ray bursts (GRBs) indicates that a newly born magnetar could be the central object of some GRBs. The observed luminosity and duration of the plateaus suggest that, for such a magnetar, a rapid spin with a sub- or millisecond period is sometimes able to last thousands of seconds. In this case, the conventional neutron star (NS) model for the magnetar may be challenged, since the rapid spin of nascent NSs would be remarkably decelerated within hundreds of seconds due to r-mode instability. In contrast, the r-modes can be effectively suppressed in nascent strange stars (SSs). In other words, to a certain extent, only SSs can keep nearly constant extremely rapid spin for a long period of time during the early ages of the stars. We thus propose that the sample of the GRB rapidly spinning magnetars can be used to test the SS hypothesis based on the distinct spin limits of NSs and SSs.

  15. The relationship between termite mound CH4/CO2 emissions and internal concentration ratios are species specific

    Science.gov (United States)

    Jamali, H.; Livesley, S. J.; Hutley, L. B.; Fest, B.; Arndt, S. K.

    2012-12-01

    1. We investigated the relative importance of CH4 and CO2 fluxes from soil and termite mounds at four different sites in the tropical savannas of Northern Australia near Darwin and assessed different methods to indirectly predict CH4 fluxes based on CO2 fluxes and internal gas concentrations. 2. The annual flux from termite mounds and surrounding soil was dominated by CO2 with large variations among sites. On a CO2-e basis, annual CH4 flux estimates from termite mounds were 5- to 46-fold smaller than the concurrent annual CO2 flux estimates. Differences between annual soil CO2 and soil CH4 (CO2-e) fluxes were even greater, soil CO2 fluxes being almost three orders of magnitude greater than soil CH4 (CO2-e) fluxes at site. 3. There were significant relationships between mound CH4 flux and mound CO2 flux, enabling the prediction of CH4 flux from measured CO2 flux, however, these relationships were clearly termite species specific. 4. We also observed significant relationships between mound flux and gas concentration inside mound, for both CH4 and CO2, and for all termite species, thereby enabling the prediction of flux from measured mound internal gas concentration. However, these relationships were also termite species specific. Using the relationship between mound internal gas concentration and flux from one species to predict mound fluxes from other termite species (as has been done in past) would result in errors of more than 5-fold for CH4 and 3-fold for CO2. 5. This study highlights that CO2 fluxes from termite mounds are generally more than one order of magnitude greater than CH4 fluxes. There are species-specific relationships between CH4 and CO2 fluxes from a~mound, and between the inside mound concentration of a gas and the mound flux emission of the same gas, but these relationships vary greatly among termite species. Consequently, there is no generic relationship that will allow for the prediction of CH4 fluxes from termite mounds of all species.

  16. Molecular Diagnostics of Supernova Remnant Shocks

    Science.gov (United States)

    Lazendic, J. S.; Wardle, M.; Green, A. J.; Whiteoak, J. B.; Burton, M. G.

    We have undertaken a study of radio and infrared molecular-line emission towards several SNRs in order to investigate molecular signatures of SNR shocks, and to test models for OH maser production in SNRs. Here we present results on G349.7+0.2.

  17. A nova outburst powered by shocks

    Science.gov (United States)

    Li, Kwan-Lok; Metzger, Brian D.; Chomiuk, Laura; Vurm, Indrek; Strader, Jay; Finzell, Thomas; Beloborodov, Andrei M.; Nelson, Thomas; Shappee, Benjamin J.; Kochanek, Christopher S.; Prieto, José L.; Kafka, Stella; Holoien, Thomas W.-S.; Thompson, Todd A.; Luckas, Paul J.; Itoh, Hiroshi

    2017-10-01

    Classical novae are runaway thermonuclear burning events on the surfaces of accreting white dwarfs in close binary star systems, sometimes appearing as new naked-eye sources in the night sky1. The standard model of novae predicts that their optical luminosity derives from energy released near the hot white dwarf, which is reprocessed through the ejected material2-5. Recent studies using the Fermi Large Area Telescope have shown that many classical novae are accompanied by gigaelectronvolt γ-ray emission6,7. This emission likely originates from strong shocks, providing new insights into the properties of nova outflows and allowing them to be used as laboratories for the study of the unknown efficiency of particle acceleration in shocks. Here, we report γ-ray and optical observations of the Milky Way nova ASASSN-16ma, which is among the brightest novae ever detected in γ-rays. The γ-ray and optical light curves show a remarkable correlation, implying that the majority of the optical light comes from reprocessed emission from shocks rather than the white dwarf8. The ratio of γ-ray to optical flux in ASASSN-16ma directly constrains the acceleration efficiency of non-thermal particles to be around 0.005, favouring hadronic models for the γ-ray emission9. The need to accelerate particles up to energies exceeding 100 gigaelectronvolts provides compelling evidence for magnetic field amplification in the shocks.

  18. Shock-wave induced mechanoluminescence: A new technique for studying effects of shock pressure on crystals

    Energy Technology Data Exchange (ETDEWEB)

    Chandra, B.P.; Parganiha, S.; Sonwane, V.D. [School of Studies in Physics and Astrophysics, Pt. Ravishankar Shukla University, Raipur 492010, Chhattisgarh (India); Chandra, V.K. [Department of Electrical and Electronics Engineering, Chhatrapati Shivaji Institute of Technology, Shivaji Nagar, Kolihapuri, Durg 491001, Chhattisgarh (India); Jha, Piyush, E-mail: piyushjha22@rediffmail.com [Department of Applied Physics, Raipur Institute of Technology, Chhatauna, Mandir Hasuad, Raipur 492101, Chhattisgarh (India); Baghel, R.N. [School of Studies in Physics and Astrophysics, Pt. Ravishankar Shukla University, Raipur 492010, Chhattisgarh (India)

    2016-10-15

    The impact of a projectile propelled to velocities in the range of 0.5–2.5 km/s on to a target (X-cut quartz crystal) produces shock waves travelling at velocity of nearly 10 km/s in target, in which intense mechanoluminescence (ML) pulses of microsecond duration are produced, both in compression and post-compression conditions. The piezoelectric field produced due to surface charges of fractured target, causes band bending and subsequently, the free charge carriers are generated in the respective bands and the emission of ML occurs. The ML appears after a delay time t{sub th} whose value decreases with increasing value of the shock pressure. Initially, the ML intensity increases with the shock pressure because of the creation of more surfaces; however, for higher values of the shock pressure, the ML intensity tends to attain a saturation value because of the hardening of the crystals due to the creation of small crystallites in which the creation of new surfaces becomes difficult. The ratio between peak ML intensity in the uncompressed region and the maximum ML intensity in the compressed region decreases with increasing shock pressure because more defects produced at high pressure generate higher barrier for the relaxation of blocked cracks under compression. The expressions derived for characteristics of shock-induced ML are able to explain satisfactorily the experimental results. Shock-wave velocity, shock pressure, transit time, lifetime of electrons in conduction band, etc. can be determined by the shock-induced ML.As such, the shock-induced ML provides a new optical technique for the studies of materials under shock pressure.

  19. Emission of β+ Particles Via Internal Pair Production in the 0+ – 0+ Transition of 90Zr: Historical Background and Current Applications in Nuclear Medicine Imaging

    Directory of Open Access Journals (Sweden)

    Marco D'Arienzo

    2013-03-01

    Full Text Available 90Y is traditionally considered as a pure β– emitter. However, the decay of this radionuclide has a minor branch to the 0+ first excited state of 90Zr at 1.76 MeV, that is followed by a β+/β– emission. This internal pair production has been largely studied in the past because it is generated by a rare electric monopole transition (E0 between the states 0+/0+ of 90Zr. The positronic emission has been recently exploited for nuclear medicine applications, i.e. positron emission tomography (PET acquisitions of 90Y-labelled radiopharmaceuticals, widely used as therapeutic agents in internal radiation therapy. To date, this topic is gaining increasing interest in the radiation dosimetry community, as the possibility of detecting β+ emissions from 90Y by PET scanners may pave the way for an accurate patient-specific dosimetry. This could lead to an explosion in scientific production in this field. In the present paper the historical background behind the study of the internal pair production of the 0+/0+ transition of 90Zr is presented along with most up to date measured branch ratio values. An overview of most recent studies that exploit β+ particles emitted from 90Y for PET acquisitions is also provided.

  20. GRB 090727 AND GAMMA-RAY BURSTS WITH EARLY-TIME OPTICAL EMISSION

    International Nuclear Information System (INIS)

    Kopač, D.; Gomboc, A.; Japelj, J.; Kobayashi, S.; Mundell, C. G.; Bersier, D.; Cano, Z.; Smith, R. J.; Steele, I. A.; Virgili, F. J.; Guidorzi, C.; Melandri, A.

    2013-01-01

    We present a multi-wavelength analysis of Swift gamma-ray burst GRB 090727, for which optical emission was detected during the prompt gamma-ray emission by the 2 m autonomous robotic Liverpool Telescope and subsequently monitored for a further two days with the Liverpool and Faulkes Telescopes. Within the context of the standard fireball model, we rule out a reverse shock origin for the early-time optical emission in GRB 090727 and instead conclude that the early-time optical flash likely corresponds to emission from an internal dissipation process. Putting GRB 090727 into a broader observational and theoretical context, we build a sample of 36 gamma-ray bursts (GRBs) with contemporaneous early-time optical and gamma-ray detections. From these GRBs, we extract a sub-sample of 18 GRBs, which show optical peaks during prompt gamma-ray emission, and perform detailed temporal and spectral analysis in gamma-ray, X-ray, and optical bands. We find that in most cases early-time optical emission shows sharp and steep behavior, and notice a rich diversity of spectral properties. Using a simple internal shock dissipation model, we show that the emission during prompt GRB phase can occur at very different frequencies via synchrotron radiation. Based on the results obtained from observations and simulation, we conclude that the standard external shock interpretation for early-time optical emission is disfavored in most cases due to sharp peaks (Δt/t < 1) and steep rise/decay indices, and that internal dissipation can explain the properties of GRBs with optical peaks during gamma-ray emission

  1. A Reverse Shock in GRB 160509A

    Science.gov (United States)

    Laskar, Tanmoy; Alexander, Kate D.; Berger, Edo; Fong, Wen-fai; Margutti, Raffaella; Shivvers, Isaac; Williams, Peter K. G.; Kopač, Drejc; Kobayashi, Shiho; Mundell, Carole; Gomboc, Andreja; Zheng, WeiKang; Menten, Karl M.; Graham, Melissa L.; Filippenko, Alexei V.

    2016-12-01

    We present the second multi-frequency radio detection of a reverse shock in a γ-ray burst. By combining our extensive radio observations of the Fermi-Large Area Telescope γ-ray burst 160509A at z = 1.17 up to 20 days after the burst with Swift X-ray observations and ground-based optical and near-infrared data, we show that the afterglow emission comprises distinct reverse shock and forward shock contributions: the reverse shock emission dominates in the radio band at ≲10 days, while the forward shock emission dominates in the X-ray, optical, and near-infrared bands. Through multi-wavelength modeling, we determine a circumburst density of {n}0≈ {10}-3 {{cm}}-3, supporting our previous suggestion that a low-density circumburst environment is conducive to the production of long-lasting reverse shock radiation in the radio band. We infer the presence of a large excess X-ray absorption column, N H ≈ 1.5 × 1022 {{cm}}-2, and a high rest-frame optical extinction, A V ≈ 3.4 mag. We identify a jet break in the X-ray light curve at {t}{jet}≈ 6 {days}, and thus derive a jet opening angle of {θ }{jet}≈ 4^\\circ , yielding a beaming-corrected kinetic energy and radiated γ-ray energy of {E}{{K}}≈ 4× {10}50 erg and {E}γ ≈ 1.3× {10}51 erg (1-104 keV, rest frame), respectively. Consistency arguments connecting the forward shocks and reverse shocks suggest a deceleration time of {t}{dec} ≈ 460 s ≈ T 90, a Lorentz factor of {{Γ }}({t}{dec})≈ 330, and a reverse-shock-to-forward-shock fractional magnetic energy density ratio of {R}{{B}}\\equiv {ɛ }{{B},{RS}}/{ɛ }{{B},{FS}}≈ 8. Our study highlights the power of rapid-response radio observations in the study of the properties and dynamics of γ-ray burst ejecta.

  2. Modeling Business Cycle with Financial Shocks Basing on Kaldor-Kalecki Model

    Directory of Open Access Journals (Sweden)

    Zhenghui Li

    2017-04-01

    Full Text Available The effects of financial factors on real business cycle is rising to one of the most popular discussions in the field of macro business cycle theory. The objective of this paper is to discuss the features of business cycle under financial shocks by quantitative technology. More precisely, we introduce financial shocks into the classical Kaldor-Kalecki business cycle model and study dynamics of the model. The shocks include external shock and internal shock, both of which are expressed as noises. The dynamics of the model can help us understand the effects of financial shocks on business cycle and improve our knowledge about financial business cycle. In the case of external shock, if the intensity of shock is less than some threshold value, the economic system behaves randomly periodically. If the intensity of shock is beyond the threshold value, the economic system will converge to a normalcy. In the case of internal shock, if the intensity of shock is less than some threshold value, the economic system behaves periodically as the case without shock. If the intensity of shock exceeds the threshold value, the economic system either behaves periodically or converges to a normalcy. It is uncertain. The case with both two kinds of shocks is more complicated. We find conditions of the intensities of shocks under which the economic system behaves randomly periodically or disorderly, or converges to normalcy. Discussions about the effects of financial shocks on the business cycle are presented.

  3. Alfven shock trains

    International Nuclear Information System (INIS)

    Malkov, M.A.; Kennel, C.F.; Wu, C.C.; Pellat, R.; Shapiro, V.D.

    1991-01-01

    The Cohen--Kulsrud--Burgers equation (CKB) is used to consider the nonlinear evolution of resistive, quasiparallel Alfven waves subject to a long-wavelength, plane-polarized, monochromatic instability. The instability saturates by nonlinear steepening, which proceeds until the periodic waveform develops an interior scale length comparable to the dissipation length; a fast or an intermediate shock then forms. The result is a periodic train of Alfven shocks of one or the other type. For propagation strictly parallel to the magnetic field, there will be two shocks per instability wavelength. Numerical integration of the time-dependent CKB equation shows that an initial, small-amplitude growing wave asymptotes to a stable, periodic stationary wave whose analytic solution specifies how the type of shock embedded in the shock train, and the amplitude and speed of the shock train, depend on the strength and phase of the instability. Waveforms observed upstream of the Earth's bowshock and cometary shocks resemble those calculated here

  4. Reflections on the international climate change negotiations: A synthesis of a working group on carbon emission policy and regulation in Brazil

    International Nuclear Information System (INIS)

    Lucon, Oswaldo; Romeiro, Viviane; Pacca, Sergio

    2013-01-01

    This short communication presents a synthesis of a Working Group on Carbon Emission Policy and Regulation held at the University of Sao Paulo, in Brazil. The document looked at the problems with the international negotiations, the options for Brazil as it attempts to control emissions, and ways to leverage the mitigation process. Several options are currently being proposed, but these are neither clear in order to support a solid polycentric approach with adequate metrics, nor a robust international coordination and a sound scientific communication. Brazil has a central role in this process, for having successful initiatives on renewable energy and deforestation control. Its leadership can demonstrate how such policies might take shape. However, the country´s future is uncertain in terms of low carbon development. Although the country is still well positioned among BRICS to find practical solutions to the stalemate in international cooperation, several internal challenges need to be harmonized. - Highlights: • The work presents results of a recent climate change mitigation policies workshop. • It assesses Brazil's potential role in shaping future policies and negotiations. • Policies are evaluated based on domestic and international effects. • Suggests how Brazil's national effort could leverage the international processes

  5. X-ray study of bow shocks in runaway stars

    Science.gov (United States)

    De Becker, M.; del Valle, M. V.; Romero, G. E.; Peri, C. S.; Benaglia, P.

    2017-11-01

    Massive runaway stars produce bow shocks through the interaction of their winds with the interstellar medium, with the prospect for particle acceleration by the shocks. These objects are consequently candidates for non-thermal emission. Our aim is to investigate the X-ray emission from these sources. We observed with XMM-Newton a sample of five bow shock runaways, which constitutes a significant improvement of the sample of bow shock runaways studied in X-rays so far. A careful analysis of the data did not reveal any X-ray emission related to the bow shocks. However, X-ray emission from the stars is detected, in agreement with the expected thermal emission from stellar winds. On the basis of background measurements we derive conservative upper limits between 0.3 and 10 keV on the bow shocks emission. Using a simple radiation model, these limits together with radio upper limits allow us to constrain some of the main physical quantities involved in the non-thermal emission processes, such as the magnetic field strength and the amount of incident infrared photons. The reasons likely responsible for the non-detection of non-thermal radiation are discussed. Finally, using energy budget arguments, we investigate the detectability of inverse Compton X-rays in a more extended sample of catalogued runaway star bow shocks. From our analysis we conclude that a clear identification of non-thermal X-rays from massive runaway bow shocks requires one order of magnitude (or higher) sensitivity improvement with respect to present observatories.

  6. System Shock: The Archetype of Operational Shock

    Science.gov (United States)

    2017-05-25

    the battle space. They can also facilitate a much greater understanding of the variables involved in each party’s decision - making process. However...system shock nests within current US Army Unified Land Operations doctrine. In order to test the utility of system shock theory to Gray Zone...23 Neil E. Harrison, “Thinking about the World We Make ” in Chaos Theory in the Social Sciences: Foundations and Applications

  7. Efficient electron heating in relativistic shocks and gamma-ray-burst afterglow.

    Science.gov (United States)

    Gedalin, M; Balikhin, M A; Eichler, D

    2008-02-01

    Electrons in shocks are efficiently energized due to the cross-shock potential, which develops because of differential deflection of electrons and ions by the magnetic field in the shock front. The electron energization is necessarily accompanied by scattering and thermalization. The mechanism is efficient in both magnetized and nonmagnetized relativistic electron-ion shocks. It is proposed that the synchrotron emission from the heated electrons in a layer of strongly enhanced magnetic field is responsible for gamma-ray-burst afterglows.

  8. Effects of Alfvénic Drift on Diffusive Shock Acceleration at Weak Cluster Shocks

    Science.gov (United States)

    Kang, Hyesung; Ryu, Dongsu

    2018-03-01

    Non-detection of γ-ray emission from galaxy clusters has challenged diffusive shock acceleration (DSA) of cosmic-ray (CR) protons at weak collisionless shocks that are expected to form in the intracluster medium. As an effort to address this problem, we here explore possible roles of Alfvén waves self-excited via resonant streaming instability during the CR acceleration at parallel shocks. The mean drift of Alfvén waves may either increase or decrease the scattering center compression ratio, depending on the postshock cross-helicity, leading to either flatter or steeper CR spectra. We first examine such effects at planar shocks, based on the transport of Alfvén waves in the small amplitude limit. For the shock parameters relevant to cluster shocks, Alfvénic drift flattens the CR spectrum slightly, resulting in a small increase of the CR acceleration efficiency, η. We then consider two additional, physically motivated cases: (1) postshock waves are isotropized via MHD and plasma processes across the shock transition, and (2) postshock waves contain only forward waves propagating along with the flow due to a possible gradient of CR pressure behind the shock. In these cases, Alfvénic drift could reduce η by as much as a factor of five for weak cluster shocks. For the canonical parameters adopted here, we suggest η ∼ 10‑4–10‑2 for shocks with sonic Mach number M s ≈ 2–3. The possible reduction of η may help ease the tension between non-detection of γ-rays from galaxy clusters and DSA predictions.

  9. 4th international exhaust gas and particulate emissions forum. Proceedings; 4. internationales FORUM Abgas- und Partikelemissionen. Beitraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Lectures of the conference addressed the following topics: European and US American pollution regulations, particulate measuring systems, emission factors for vehicles, particulate emission abatement through simulation and optimization, selective catalytic reduction in heavy duty diesel trucks, filters, combustion properties, performance assessment, contribution of biofuels. (uke)

  10. Magnetic Fields Recorded by Chondrules Formed in Nebular Shocks

    Science.gov (United States)

    Mai, Chuhong; Desch, Steven J.; Boley, Aaron C.; Weiss, Benjamin P.

    2018-04-01

    Recent laboratory efforts have constrained the remanent magnetizations of chondrules and the magnetic field strengths to which the chondrules were exposed as they cooled below their Curie points. An outstanding question is whether the inferred paleofields represent the background magnetic field of the solar nebula or were unique to the chondrule-forming environment. We investigate the amplification of the magnetic field above background values for two proposed chondrule formation mechanisms, large-scale nebular shocks and planetary bow shocks. Behind large-scale shocks, the magnetic field parallel to the shock front is amplified by factors of ∼10–30, regardless of the magnetic diffusivity. Therefore, chondrules melted in these shocks probably recorded an amplified magnetic field. Behind planetary bow shocks, the field amplification is sensitive to the magnetic diffusivity. We compute the gas properties behind a bow shock around a 3000 km radius planetary embryo, with and without atmospheres, using hydrodynamics models. We calculate the ionization state of the hot, shocked gas, including thermionic emission from dust, thermal ionization of gas-phase potassium atoms, and the magnetic diffusivity due to Ohmic dissipation and ambipolar diffusion. We find that the diffusivity is sufficiently large that magnetic fields have already relaxed to background values in the shock downstream where chondrules acquire magnetizations, and that these locations are sufficiently far from the planetary embryos that chondrules should not have recorded a significant putative dynamo field generated on these bodies. We conclude that, if melted in planetary bow shocks, chondrules probably recorded the background nebular field.

  11. Do structural oil-market shocks affect stock prices?

    International Nuclear Information System (INIS)

    Apergis, Nicholas; Miller, Stephen M.

    2009-01-01

    This paper investigates how explicit structural shocks that characterize the endogenous character of oil price changes affect stock-market returns in a sample of eight countries - Australia, Canada, France, Germany, Italy, Japan, the United Kingdom, and the United States. For each country, the analysis proceeds in two steps. First, modifying the procedure of Kilian [Not All Oil Price Shocks are Alike: Disentangling Demand and Supply Shocks in the Crude Oil Market. American Economic Review.], we employ a vector error-correction or vector autoregressive model to decompose oil-price changes into three components: oil-supply shocks, global aggregate-demand shocks, and global oil-demand shocks. The last component relates to specific idiosyncratic features of the oil market, such as changes in the precautionary demand concerning the uncertainty about the availability of future oil supplies. Second, recovering the oil-supply shocks, global aggregate-demand shocks, and global oil-demand shocks from the first analysis, we then employ a vector autoregressive model to determine the effects of these structural shocks on the stock market returns in our sample of eight countries. We find that international stock market returns do not respond in a large way to oil market shocks. That is, the significant effects that exist prove small in magnitude. (author)

  12. Vulnerability to shocks in the global seafood trade network

    Science.gov (United States)

    Gephart, Jessica A.; Rovenskaya, Elena; Dieckmann, Ulf; Pace, Michael L.; Brännström, Åke

    2016-03-01

    Trade can allow countries to overcome local or regional losses (shocks) to their food supply, but reliance on international food trade also exposes countries to risks from external perturbations. Countries that are nutritionally or economically dependent on international trade of a commodity may be adversely affected by such shocks. While exposure to shocks has been studied in financial markets, communication networks, and some infrastructure systems, it has received less attention in food-trade networks. Here, we develop a forward shock-propagation model to quantify how trade flows are redistributed under a range of shock scenarios and assess the food-security outcomes by comparing changes in national fish supplies to indices of each country’s nutritional fish dependency. Shock propagation and distribution among regions are modeled on a network of historical bilateral seafood trade data from UN Comtrade using 205 reporting territories grouped into 18 regions. In our model exposure to shocks increases with total imports and the number of import partners. We find that Central and West Africa are the most vulnerable to shocks, with their vulnerability increasing when a willingness-to-pay proxy is included. These findings suggest that countries can reduce their overall vulnerability to shocks by reducing reliance on imports and diversifying food sources. As international seafood trade grows, identifying these types of potential risks and vulnerabilities is important to build a more resilient food system.

  13. External Shock in a Multi-bursting Gamma-Ray Burst: Energy Injection Phase Induced by the Later Launched Ejecta

    Science.gov (United States)

    Lin, Da-Bin; Huang, Bao-Quan; Liu, Tong; Gu, Wei-Min; Mu, Hui-Jun; Liang, En-Wei

    2018-01-01

    Central engines of gamma-ray bursts (GRBs) may be intermittent and launch several episodes of ejecta separated by a long quiescent interval. In this scenario, an external shock is formed due to the propagation of the first launched ejecta into the circum-burst medium and the later launched ejecta may interact with the external shock at a later period. Owing to the internal dissipation, the later launched ejecta may be observed at a later time (t jet). In this paper, we study the relation of t b and t jet, where t b is the collision time of the later launched ejecta with the formed external shock. It is found that the relation of t b and t jet depends on the bulk Lorentz factor (Γjet) of the later launched ejecta and the density (ρ) of the circum-burst medium. If the value of Γjet or ρ is low, the t b would be significantly larger than t jet. However, the t b ∼ t jet can be found if the value of Γjet or ρ is significantly large. Our results can explain the large lag of the optical emission relative to the γ-ray/X-ray emission in GRBs, e.g., GRB 111209A. For GRBs with a precursor, our results suggest that the energy injection into the external shock and thus more than one external-reverse shock may appear in the main prompt emission phase. According to our model, we estimate the Lorentz factor of the second launched ejecta in GRB 160625B.

  14. Ultraviolet continuum and H2 fluorescent emission in Herbig-Haro objects 43 and 47

    International Nuclear Information System (INIS)

    Schwartz, R.D.

    1983-01-01

    The results of International Ultraviolet Explorer (IUE) short-wavelength spectra of the low-excitation Herbig-Haro objects HH 43 and HH 47 are reported. In HH 43 a number of emission lines in the Lyman band of H 2 from the excited state 1 μ + /sub u/, #betta#' = 1, J' = 4 are observed. The lines are produced by fluorescence from the H Lyα line which pumps the lower state 1 μ + /sub g/, #betta#'' = 2.J'' = 5 which in turn is excited by a low-velocity shock wave. No evidence of emission from highly ionized gas is present in the UV spectra. Both objects exhibit a UV continuum which peaks in the vicinity of 1500 A and which is probably caused by hydrogen two-photon emission enhanced by collisional excitation in a low-velocity shock

  15. Instruments to reduce pollutant emissions of the existing inland vessel fleet. Position paper for international workshop 'Emissions from the Legacy Fleet'

    Energy Technology Data Exchange (ETDEWEB)

    Den Boer, E.

    2011-11-15

    Inland waterway transport (IWT) has a key performance on the GHG emissions per tonne kilometre shipped. Due to its potential to limit climate change, the recent EU Transport White Paper has set high goals for the non-road modes. The Ports of Rotterdam (NL), Antwerp (BE) and others strive to increase the use of IWT in their hinterland transport. The Port of Rotterdam authority has imposed a modal split on the newly built container terminals, thus increasing the use of rail and IWT. The growth is estimated to result in a quadrupling of inland barge container traffic on the Rhine corridor in the timeframe 2010-2035. Local air quality is another environmental issue, however, that plays a key role. Due to reasons of long ship engine lifetimes and progress made in road transport emissions, IWT needs to improve its air pollution profile. To turn the potential of IWT into real growth, it is important to: improve the air pollutant profile of inland shipping; take responsibility to maintain the air quality levels along inland waterway corridors over Europe, especially in urban areas where road transport, industry and IWT contribute to levels that will need to be in accordance with the EU air quality directive 2008/51. A new set of standards for new engines will shortly be proposed by the European Commission to be introduced in 2016. However, these will probably not be as tight as the Euro-VI standards for road transport. In addition, the long lifetime of inland barge engines (30,000 to over 200,000 hours, depending on the engine type) will result in a slow uptake of the phase-IV engines in the fleet. The German and Dutch authorities have the opinion that not only the air pollutant emissions of new engines need to be curbed, but deliberate over the development of instruments that will reduce the pollutant emissions of the existing fleet (legacy fleet), in addition to the limitedly effective subsidy schemes applied in recent years. This paper demonstrates the need for measures

  16. SN 1987 A: A Unique Laboratory for Shock Physics

    Science.gov (United States)

    Sonneborn, George

    2012-01-01

    Supernova 1987 A has given us an unprecedented view of the evolution of the explosion debris and its interaction with circumstellar matter. The outer supernova debris, now expanding with velocities approx.8000 km/s, encountered the relatively dense circumstellar ring formed by presupernova mass loss in the early 1990s. The shock interaction is manifested by UV-optical "hotspots", an expanding X-ray ring, an expanding ring of knotty non-thermal radio emission, and a ring of thermal IR emission from silicate dust Recent ultraviolet observations of the emissions from the reverse shock and the ring with the HST/COS reveal new details about the shock interaction. Lyman alpha emission from the reverse shock is much stronger than H alpha and they have different emission morphologies, pointing to different emission mechanisms. The reverse shock was detected for the first time in C IV 1550. The N V to C IV brightness ratio indicates the N/C abundance ratio in the expanding debris is about 100X solar, about 3X N/C in the inner ring.

  17. Test Report - StoveTeam International, Ecocina Stove with Wood Fuel - Air Pollutant Emissions and Fuel Efficiency

    Science.gov (United States)

    Test results were obtained in accordance with ISO (International Organization for Standardization) IWA (International Workshop Agreement) 11:2012 that was unanimously affirmed by more than 90 stakeholders at the ISO International Workshop on Cookstoves on February 28-29, 2012 in ...

  18. Investigation on the Effects of Internal EGR by Variable Exhaust Valve Actuation with Post Injection on Auto-ignited Combustion and Emission Performance

    Directory of Open Access Journals (Sweden)

    Insu Cho

    2018-04-01

    Full Text Available Variable valve mechanisms are usually applied to a gasoline combustion engine to improve its power performance by controlling the amount of intake air according to the operating load. These mechanisms offer one possibility of resolving the conflict of objectives between a further reduction of raw emissions and an improvement in fuel efficiency. In recent years, variable valve control systems have become extremely important in the diesel combustion engine. Importantly, it has been shown that there are several potential benefits of applying variable valve timing (VVT to a compression ignition engine. Valve train variability could offer one option to achieve the reduction goals of engine-out emissions and fuel consumption. The aim of this study was to investigate the effects on part load combustion and emission performance of internal exhaust gas recirculation (EGR by variable exhaust valve lift actuation using a cam-in-cam system, which is an electronically variable valve device with a variable inside cam retarded to about 30 degrees. Numerical simulation based on GT-POWER has been performed to predict the NOx reduction strategy at the part load operating point of 1200 rpm in a four-valve diesel engine. A GT-POWER model of a common-rail direct injection engine with internal EGR was built and verified with experimental data. As a result, large potential for reducing NOx emissions through the use of exhaust valve control has been identified. Namely, it is possible to utilize heat efficiently as recompression of retarded post injection with downscaled specification of the exhaust valve rather than the intake valve, even if the CIC V1 condition with a reduction of the exhaust valve has a higher internal EGR rate of about 2% compared to that of the CIC V2 condition.

  19. Hydraulic shock absorbers

    International Nuclear Information System (INIS)

    Thatcher, G.; Davidson, D. F.

    1984-01-01

    A hydraulic shock absorber of the dash pot kind for use with electrically conducting liquid such as sodium, has magnet means for electro magnetically braking a stream of liquid discharged from the cylinder. The shock absorber finds use in a liquid metal cooled nuclear reactor for arresting control rods

  20. Our Favorite Film Shocks

    DEFF Research Database (Denmark)

    Willerslev, Rane; Suhr, Christian

    2014-01-01

    The modern medium of film has long been hailed for its capacity for producing shocks of an entertaining, thought-provoking, or even politically emancipative nature. But what is a shock, how and when does it occur, how long does it last, and are there particular techniques for producing cinematic...

  1. Climate shocks and conflict

    NARCIS (Netherlands)

    Papaioannou, Kostadis J.

    2016-01-01

    This paper offers a historical micro-level analysis of the impact of climate shocks on the incidence of civil conflict in colonial Nigeria (1912-1945). Primary historical sources on court cases, prisoners and homicides are used to capture conflict. To measure climate shocks we use the deviation

  2. Elaboration of the international transfer mechanism of reduction in greenhouse gas emissions on the basis of the Russian federal law About agreements of products sharing'

    International Nuclear Information System (INIS)

    Toivonen, N.R.; Koulikovskaya, L.

    2001-01-01

    Suggestions for a comprehensive legal framework for the implementation in Russia of the flexibility mechanisms established under the Kyoto Protocol (i.e. joint implementation; clean development mechanism; international emissions trading) are proposed. It is suggested that the legal framework be established using the principles embodied in the existing Russian federal law, 'About agreements of product sharing' adopted in 1995. As a basic requirement, it is suggested that the new federal law must include the fundamental elements required to create possibilities for the Russian Federation to participate in the process of certified emission reductions (CER) transfer, emissions reduction unit (ERU) negotiation, and adjusted amount units (AAU) trading within the framework of the Kyoto Protocol implementation. The new law must also embody the basic procedures required to enter into agreements at the international, inter-regional and inter-sectoral levels. Failure to develop the legislative support and the legal framework to facilitate valid Russian participation in the implementation of the Kyoto Protocol will prevent many valuable initiatives and projects from being realized

  3. Latin America multidisciplinary research on heat shock proteins and cell stress: proceedings of the first conference of the Latin America Chapter of the Cell Stress Society International.

    Science.gov (United States)

    Bausero, María A

    2015-09-01

    The First Conference of the Latin America Chapter of the Cell Stress Society International (CSSI) organized by CSSI was held in Montevideo, Uruguay, on March 11-14, 2014. The Latin America Chapter of the CSSI (LAC-CSSI) was established at the Workshop on the Molecular Biology of the Stress Response, Porto Alegre, Brazil, May 2012. The chapter's first meeting took place in the beautiful city of Montevideo and was chaired by the first (LAC-CSSI) elected president Professor María Bausero. Forty-two invited speakers presented their work to more than 100 scientists. The first day of the conference was dedicated to an introductory program for students, young investigators, and participants new to the field of molecular chaperones and the stress response. These seminars were held in the Pasteur Institute of Montevideo and the Faculty of Sciences of the University of the Republic. These institutions were carefully selected to give foreign participants a broad view of the diversity of students and institutions doing research in Uruguay, as well as an opportunity for direct interaction with our scientists and students. Invited speakers for the seminar series were Dr. Wolfgang Schumann, Dr. Cristina Bonorino, Dr. Antonio De Maio, Dr. Ian Brown, Dr. Rafael Radi, Dr. Daniel Ciocca, and Dr. Celia Quijano. The remaining days of the conference took place at the Sheraton Hotel in Montevideo, and the scientific sessions are discussed below.

  4. International

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    This rubric reports on 10 short notes about international economical facts about nuclear power: Electricite de France (EdF) and its assistance and management contracts with Eastern Europe countries (Poland, Hungary, Bulgaria); Transnuclear Inc. company (a 100% Cogema daughter company) acquired the US Vectra Technologies company; the construction of the Khumo nuclear power plant in Northern Korea plays in favour of the reconciliation between Northern and Southern Korea; the delivery of two VVER 1000 Russian reactors to China; the enforcement of the cooperation agreement between Euratom and Argentina; Japan requested for the financing of a Russian fast breeder reactor; Russia has planned to sell a floating barge-type nuclear power plant to Indonesia; the control of the Swedish reactor vessels of Sydkraft AB company committed to Tractebel (Belgium); the renewal of the nuclear cooperation agreement between Swiss and USA; the call for bids from the Turkish TEAS electric power company for the building of the Akkuyu nuclear power plant answered by three candidates: Atomic Energy of Canada Limited (AECL), Westinghouse (US) and the French-German NPI company. (J.S.)

  5. Dynamical efficiency of collisionless magnetized shocks in relativistic jets

    Science.gov (United States)

    Aloy, Miguel A.; Mimica, Petar

    2011-09-01

    The so-called internal shock model aims to explain the light-curves and spectra produced by non-thermal processes originated in the flow of blazars and gamma-ray bursts. A long standing question is whether the tenuous collisionless shocks, driven inside a relativistic flow, are efficient enough to explain the amount of energy observed as compared with the expected kinetic power of the outflow. In this work we study the dynamic efficiency of conversion of kinetic-to-thermal/magnetic energy of internal shocks in relativistic magnetized outflows. We find that the collision between shells with a non-zero relative velocity can yield either two oppositely moving shocks (in the frame where the contact surface is at rest), or a reverse shock and a forward rarefaction. For moderately magnetized shocks (magnetization σ ~= 0.1), the dynamic efficiency in a single two-shell interaction can be as large as 40%. Hence, the dynamic efficiency of moderately magnetized shocks is larger than in the corresponding unmagnetized two-shell interaction. We find that the efficiency is only weakly dependent on the Lorentz factor of the shells and, thus internal shocks in the magnetized flow of blazars and gamma-ray bursts are approximately equally efficient.

  6. An observation of histological evidence on internal organ damages in mice caused by repeated exposures to motorcycle emissions

    Science.gov (United States)

    Wardoyo, Arinto Y. P.; Juswono, Unggul P.; Noor, Johan A. E.

    2017-05-01

    Motor vehicle emissions have been identified as a source of ultrafine particles, which have significant impacts on human health. Repeated and prolonged exposure to ultrafine particles may have a significant association with organ damage. Here, we evaluated the correlation between repeated exposure to ultrafine particles and organ damage in mice. Motorcycle emissions were injected into an exposure chamber with mice for a period of 20 seconds. This treatment was conducted over 10 days. The mice were sacrificed on the 2nd, 4th, 6th, 8th, and 10th days for organ preparations. Based on the results, motorcycle emission exposure caused organ damage in mice, with different severities depending on the organ. The highest damage was found for the lung, followed by the kidney, erythrocytes, and liver.

  7. A comparative evaluation on the emission characteristics of ceramic and metallic catalytic converter in internal combustion engine

    Science.gov (United States)

    Leman, A. M.; Jajuli, Afiqah; Rahman, Fakhrurrazi; Feriyanto, Dafit; Zakaria, Supaat

    2017-09-01

    Enforcement of a stricter regulation on exhaust emission by many countries has led to utilization of catalytic converter to reduce the harmful pollutant emission. Ceramic and metallic catalytic converters are the most common type of catalytic converter used. The purpose of this study is to evaluate the performance of the ceramic and metallic catalytic converter on its conversion efficiency using experimental measurement. Both catalysts were placed on a modified exhaust system equipped with a Mitshubishi 4G93 single cylinder petrol engine that was tested on an eddy current dynamometer under steady state conditions for several engine speeds. The experimental results show that the metallic catalytic converter reduced a higher percentage of CO up to 98.6% reduction emissions while ceramic catalytic converter had a better reduction efficiency of HC up to 85.4% and 87.2% reduction of NOx.

  8. Experimental study on emissions and performance of an internal combustion engine fueled with gasoline and gasoline/n-butanol blends

    International Nuclear Information System (INIS)

    Elfasakhany, Ashraf

    2014-01-01

    Highlights: • Using of 3 and 7 vol.% n-butanol blends in SI engine is studied for the first time. • Engine performance and emissions depend on both engine speed and blend rates. • CO and UHC for blended fuels are maximum at 3000–3100 r/min. • The higher the rate of n-butanol, the lower the emissions and performance. • This study strongly supports using low blend rates of n-butanol (<10 vol.%) in ICE. - Abstract: In this paper, exhaust emissions and engine performance have been experimentally studied for neat gasoline and gasoline/n-butanol blends in a wide range of working speeds (2600–3400 r/min) without any tuning or modification on the gasoline engine systems. The experiment has the ability of evaluating performance and emission characteristics, such as break power, torque, in-cylinder pressure, volumetric efficiency, exhaust gas temperature and concentrations of CO 2 , CO and UHC. Results of the engine test indicated that using n-butanol–gasoline blended fuels slightly decrease the output torque, power, volumetric efficiency, exhaust gas temperature and in-cylinder pressure of the engine as a result of the leaning effect caused by the n-butanol addition; CO, CO 2 and UHC emissions decrease dramatically for blended fuels compared to neat gasoline because of the improved combustion since n-butanol has extra oxygen, which allows partial reduction of the CO and UHC through formation of CO 2 . It was also noted that the exhaust emissions depend on the engine speed rather than the n-butanol contents

  9. Emissions from international shipping. Pt. 2: Impact of future technologies - scenarios for the years 2020 and 2050

    International Nuclear Information System (INIS)

    Eyring, V.; Lauer, A.; Lemper, B.

    2004-01-01

    We use the today's fleet-average emission factors of the most important ship exhausts to calculate emission scenarios for the future. To develop plausible future scenarios we first discuss upcoming regulations and compliance with future regulations through technological improvements. We present geographically resolved emission inventory forecast scenarios for the years 2020 and 2050. The scenarios are based on some very strict assumptions of future ship traffic demand and technological improvements. The future ship traffic demand scenario is mainly determined by the economic growth and the growth in world seaborne trade and distinguishes between different ship types. The annual growth rates of sea trade volumes and expected vessel traffic density is assumed to be smaller for today's most frequently sailed routes (in particular east-west-trades) than for those that are currently less frequently sailed (in particular south-north-trades). This leads to an adjustment of the number of ships sailing the different shipping routes in 2020 and even stronger in 2050. For the future technology scenarios we assume a diesel-only fleet in 2020 resulting in an estimated fuel consumption of 422 million metric tons (Mt) and 1226 Tg CO 2 emissions. For 2050 one scenario for fuel consumption assumes that 25% of the fuel consumed by a diesel-only fleet can be saved by using future alternative propulsion plants, resulting in a fuel consumption of 422 Mt and 1339 Tg CO 2 emissions in 2050. The other scenario is a business-as-usual scenario for a diesel-only fleet even in 2050 and gives an estimate of 646 Mt and 1783 Tg CO 2 emissions in 2050. Dependent on how rapid technology improvements for diesel engines are introduced we present four different technology scenarios. (orig.)

  10. Is shock index associated with outcome in children with sepsis/septic shock?*.

    Science.gov (United States)

    Yasaka, Yuki; Khemani, Robinder G; Markovitz, Barry P

    2013-10-01

    To investigate the association between PICU shock index (the ratio of heart rate to systolic blood pressure) and PICU mortality in children with sepsis/septic shock. To explore cutoff values for shock index for ICU mortality, how change in shock index over the first 6 hours of ICU admission is associated with outcome, and how the use of vasoactive therapy may affect shock index and its association with outcome. Retrospective cohort. Single-center tertiary PICU. Five hundred forty-four children with the diagnosis of sepsis/septic shock. None. From January 2003 to December 2009, 544 children met International Pediatric Sepsis Consensus Conference of 2005 criteria for sepsis/septic shock. Overall mortality was 23.7%. Among all patients, hourly shock index was associated with mortality: odds ratio of ICU mortality at 0 hour, 1.08, 95% CI (1.04-1.12); odds ratio at 1 hour, 1.09 (1.04-1.13); odds ratio at 2 hours, 1.09 (1.05-1.13); and odds ratio at 6 hours, 1.11 (1.06-1.15). When stratified by age, early shock index was associated with mortality only in children 1-3 and more than or equal to 12 years old. Area under the receiver operating characteristic curve in age 1-3 and more than or equal to 12 years old for shock index at admission was 0.69 (95% CI, 0.58-0.80) and 0.62 (95% CI, 0.52-0.72) respectively, indicating a fair predictive marker. Although higher shock index was associated with increased risk of mortality, there was no particular cutoff value with adequate positive or negative likelihood ratios to identify mortality in any age group of children. The improvement of shock index in the first 6 hours of ICU admission was not associated with outcome when analyzed in all patients. However, among patients whose shock index were above the 50th percentile at ICU admission for each age group, improvement of shock index was associated with lower ICU mortality in children between 1-3 and more than or equal to 12 years old (p = 0.02 and p = 0.03, respectively). When

  11. Shock-induced luminescence from Z-cut lithium niobate

    International Nuclear Information System (INIS)

    Brannon, P.J.; Morris, R.W.; Asay, J.R.

    1985-01-01

    Shock-induced luminescence from lithium niobate has been studied in the stress range 1.6--21.0 GPa. Both fast-framing photography and five-channel optical pyrometry were used to observe the luminescence. The framing photography showed that the emission pattern is heterogeneous for stresses just above the dynamic yield point. A further increase of the stress resulted in a pattern which was essentially homogeneous to within the experimental spatial resolution of about 30 μm. Narrowband filters and photomultiplier tubes were used in the optical pyrometry experiments. A broadband spectrum with a peak near 700 nm was observed. A plot of the energy dissipated by the shock versus shock stress correlates very well with a plot of the 700-nm intensity versus shock stress. The mechanism for light emission in lithium niobate appears to be closely related to the dynamic yielding process

  12. Collisionless shock waves

    International Nuclear Information System (INIS)

    Sagdeev, R.Z.; Kennel, C.F.

    1991-01-01

    Collisionless shocks cannot occur naturally on the earth, because nearly all matter here consists of electrically neutral atoms and molecules. In space, however, high temperatures and ultraviolet radiation from hot stars decompose atoms into their constituent nuclei and electrons, producing a soup of electrically charged particles known as a plasma. Plasma physicists proposed that the collective electrical and magnetic properties of plasmas could produce interactions that take the place of collisions and permit shocks to form. In 1964 the theoretical work found its first experimental confirmation. Norman F. Ness and his colleagues at the Goddard Space Flight Center, using data collected from the iMP-1 spacecraft, detected clear signs that a collisionless shock exists where the solar wind encounters the earth's magnetic field. More recent research has demonstrated that collisionless shocks appear in a dazzling array of astronomical settings. For example, shocks have been found in the solar wind upstream (sunward) of all the planet and comets that have been visited by spacecraft. Violent flares on the sun generate shocks that propagate to the far reaches of the solar system; tremendous galactic outbursts create disruptions in the intergalactic medium that are trillions of times larger. In addition, many astrophysicists think that shocks from supernova explosions in our galaxy accelerate cosmic rays, a class of extraordinarily energetic elementary particles and atomic nuclei that rain down on the earth from all directions

  13. HIGH-ENERGY NON-THERMAL AND THERMAL EMISSION FROM GRB 141207A DETECTED BY FERMI

    Energy Technology Data Exchange (ETDEWEB)

    Arimoto, Makoto [Research Institute for Science and Engineering, Waseda University, 3-4-1, Ohkubo, Shinjuku, Tokyo, 169-8555 (Japan); Asano, Katsuaki [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8582 (Japan); Ohno, Masanori [Department of Physical Sciences, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8526 (Japan); Veres, Péter [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Axelsson, Magnus [KTH Royal Institute of Technology, Department of Physics, SE-106 91 Stockholm (Sweden); Bissaldi, Elisabetta [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, I-70126 Bari (Italy); Tachibana, Yutaro; Kawai, Nobuyuki, E-mail: m.arimoto@aoni.waseda.jp [Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo, 152-8551 (Japan)

    2016-12-20

    A bright long gamma-ray burst GRB 141207A was observed by the Fermi Gamma-ray Space Telescope and detected by both instruments onboard. The observations show that the spectrum in the prompt phase is not well described by the canonical empirical Band function alone, and that an additional power-law component is needed. In the early phase of the prompt emission, a modified blackbody with a hard low-energy photon index ( α  = +0.2 to +0.4) is detected, which suggests a photospheric origin. In a finely time-resolved analysis, the spectra are also well fitted by the modified blackbody combined with a power-law function. We discuss the physical parameters of the photosphere such as the bulk Lorentz factor of the relativistic flow and the radius. We also discuss the physical origin of the extra power-law component observed during the prompt phase in the context of different models such as leptonic and hadronic scenarios in the internal shock regime and synchrotron emission in the external forward shock. In the afterglow phase, the temporal and spectral behaviors of the temporally extended high-energy emission and the fading X-ray emission detected by the X-Ray Telescope on-board Swift are consistent with synchrotron emission in a radiative external forward shock.

  14. X-RAY SIGNATURES OF NON-EQUILIBRIUM IONIZATION EFFECTS IN GALAXY CLUSTER ACCRETION SHOCK REGIONS

    International Nuclear Information System (INIS)

    Wong, Ka-Wah; Sarazin, Craig L.; Ji Li

    2011-01-01

    The densities in the outer regions of clusters of galaxies are very low, and the collisional timescales are very long. As a result, heavy elements will be under-ionized after they have passed through the accretion shock. We have studied systematically the effects of non-equilibrium ionization for relaxed clusters in the ΛCDM cosmology using one-dimensional hydrodynamic simulations. We found that non-equilibrium ionization effects do not depend on cluster mass, but depend strongly on redshift which can be understood by self-similar scaling arguments. The effects are stronger for clusters at lower redshifts. We present X-ray signatures such as surface brightness profiles and emission lines in detail for a massive cluster at low redshift. In general, soft emission (0.3-1.0 keV) is enhanced significantly by under-ionization, and the enhancement can be nearly an order of magnitude near the shock radius. The most prominent non-equilibrium ionization signature we found is the O VII and O VIII line ratio. The ratios for non-equilibrium ionization and collisional ionization equilibrium models are different by more than an order of magnitude at radii beyond half of the shock radius. These non-equilibrium ionization signatures are equally strong for models with different non-adiabatic shock electron heating efficiencies. We have also calculated the detectability of the O VII and O VIII lines with the future International X-ray Observatory (IXO). Depending on the line ratio measured, we conclude that an exposure of ∼130-380 ks on a moderate-redshift, massive regular cluster with the X-ray Microcalorimeter Spectrometer (XMS) on the IXO will be sufficient to provide a strong test for the non-equilibrium ionization model.

  15. H2 profiles of C-type bow shocks

    International Nuclear Information System (INIS)

    Smith, M.D.; Brand, P.W.J.L.

    1990-01-01

    We present emission-line profiles of molecular hydrogen from curved C-shocks within molecular clouds. Shock configurations arising from the supersonic motion of jets and bullets within a dense cloud are chosen. Bow shock speeds in the range υ w = 40-200 km s -1 are investigated. Breakdown through dissociation and self-ionization restricts the C-shock section to the bow tail. We find that profiles are essentially single-peaked and narrow with full widths (at 10 per cent maximum intensity, deconvolved) of up to about 50, 40 and 30 km s -1 for cones, hemispherical caps and paraboloids, respectively. Exceptional field alignments can produce lines as wide as 75 km s -1 in the conical shock model. (author)

  16. Broad band simulation of Gamma Ray Bursts (GRB) prompt emission in presence of an external magnetic field

    Science.gov (United States)

    Ziaeepour, Houri; Gardner, Brian

    2011-12-01

    The origin of prompt emission in GRBs is not yet well understood. The simplest and most popular model is Synchrotron Self-Compton (SSC) emission produced by internal shocks inside an ultra-relativistic jet. However, recent observations of a delayed high energy component by the Fermi-LAT instrument have encouraged alternative models. Here we use a recently developed formulation of relativistic shocks for GRBs to simulate light curves and spectra of synchrotron and self-Compton emissions in the framework of internal shock model. This model takes into account the evolution of quantities such as densities of colliding shells, and fraction of kinetic energy transferred to electrons and to induced magnetic field. We also extend this formulation by considering the presence of a precessing external magnetic field. These simulations are very realistic and present significant improvement with respect to previous phenomenological GRB simulations. They reproduce light curves of separate peaks of real GRBs and variety of spectral slopes at E > Epeak observed by the Fermi-LAT instrument. The high energy emission can be explained by synchrotron emission and a subdominant contribution from inverse Compton. We also suggest an explanation for extended tail emission and relate it to the screening of the magnetic field and/or trapping of accelerated electrons in the electromagnetic energy structure of the plasma in the shock front. Spectral slopes of simulated bursts at E external magnetic field, we show that due to the fast variation of other quantities, its signature in the Power Distribution Spectrum (PDS) is significantly suppressed and only when the duration of the burst is few times longer than the oscillation period it can be detected, otherwise either it is confused with the Poisson noise or with intrinsic variations of the emission. Therefore, low significant oscillations observed in the PDS of GRB 090709a are most probably due to a precessing magnetic field.

  17. Experimental Shock Transformation of Gypsum to Anhydrite: A New Low Pressure Regime Shock Indicator

    Science.gov (United States)

    Bell, Mary S.; Zolensky, Michael E.

    2011-01-01

    The shock behavior of gypsum is important in understanding the Cretaceous/Paleogene event and other terrestrial impacts that contain evaporite sediments in their targets (e.g., Mars Exploration Rover Spirit detected sulfate at Gusev crater, [1]). Most interest focuses on issues of devolatilization to quantify the production of SO2 to better understand its role in generating a temporary atmosphere and its effects on climate and biota [2,3]. Kondo and Ahrens [4] measured induced radiation emitted from single crystal gypsum shocked to 30 and 40 GPa. They observed greybody emission spectra corresponding to temperatures in the range of 3,000 to 4,000 K that are a factor of 2 to 10 times greater than calculated pressure-density energy equation of state temperatures (Hugoniot) and are high enough to melt gypsum. Chen et al. [5] reported results of shock experiments on anhydrite, gypsum, and mixtures of these phases with silica. Their observations indicated little or no devolatilization of anhydrite shocked to 42 GPa and that the fraction of sulfur, by mass, that degassed is approx.10(exp -2) of theoretical prediction. In another report of shock experiments on calcite, anhydrite, and gypsum, Badjukov et al. [6] observed only intensive plastic deformation in anhydrite shock loaded at 63 GPa, and gypsum converted to anhydrite when shock loaded at 56 GPa but have not experimentally shocked gypsum in a step-wise manner to constrain possible incipient transformation effects. Schmitt and Hornemann [7] shock loaded anhydrite and quartz to a peak pressure of 60 GPa and report the platy anhydrite grains were completely pseudomorphed by small crystallized anhydrite grains. However, no evidence of interaction between the two phases could be observed and they suggested that recrystallization of anhydrite grains is the result of a solid-state transformation. They concluded that significant decomposition of anhydrite requires shock pressures higher than 60 GPa. Gupta et al. [8

  18. Pediatric Toxic Shock Syndrome

    Directory of Open Access Journals (Sweden)

    Jennifer Yee

    2017-09-01

    Full Text Available Audience: This scenario was developed to educate emergency medicine residents on the diagnosis and management of a pediatric patient with toxic shock syndrome. The case is also appropriate for teaching of medical students and advanced practice providers, as well as a review of the principles of crisis resource management, teamwork, and communication. Introduction: Toxic shock syndrome is a low-frequency, high-acuity scenario requiring timely identification and aggressive management. If patients suffering from this condition are managed incorrectly, they may progress into multi-organ dysfunction and potentially death. Toxic shock syndrome has been associated with Streptococcus and Staphylococcus aureus (Staph. Approximately half of Staph cases are associated with menstruation, which was first described in the 1970s-1980s and was associated with the use of absorbent tampons.1 Group A Streptococcus may cause complications such as necrotizing fasciitis and gangrenous myositis.2 Pediatric patients may present critically ill from toxic shock syndrome. Providers need to perform a thorough history and physical exam to discern the source of infection. Management requires aggressive care with antibiotics and IV fluids. Objectives: By the end of this simulation session, the learner will be able to: 1 Recognize toxic shock syndrome. 2 Review the importance of a thorough physical exam. 3 Discuss management of toxic shock syndrome, including supportive care and the difference in antibiotic choices for streptococcal and staphylococcal toxic shock syndrome. 4 Appropriately disposition a patient suffering from toxic shock syndrome. 5 Communicate effectively with team members and nursing staff during a resuscitation of a critically ill patient. Method: This session was conducted using high-fidelity simulation, followed by a debriefing session and lecture on toxic shock syndrome.

  19. Shocks near Jamming

    Science.gov (United States)

    Gómez, Leopoldo R.; Turner, Ari M.; van Hecke, Martin; Vitelli, Vincenzo

    2012-02-01

    Nonlinear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they jam, these fragile and disordered solids exhibit a vanishing rigidity and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are dynamically compressed and demonstrate that the elementary excitations are strongly nonlinear shocks, rather than ordinary phonons. We capture the full dependence of the shock speed on pressure and impact intensity by a surprisingly simple analytical model.

  20. Mechanical shock absorber

    International Nuclear Information System (INIS)

    Vrillon, Bernard.

    1973-01-01

    The mechanical shock absorber described is made of a constant thickness plate pierced with circular holes regularly distributed in such a manner that for all the directions along which the strain is applied during the shock, the same section of the substance forming the plate is achieved. The shock absorber is made in a metal standing up to extensive deformation before breaking, selected from a group comprising mild steels and austenitic stainless steels. This apparatus is used for handling pots of fast neutron reactor fuel elements [fr

  1. Shock formation of HCO+

    International Nuclear Information System (INIS)

    Elitzur, M.

    1983-01-01

    It is shown that shocks propagating in dense molecular regions will lead to a decrease in HCO + relative abundance, in agreement with previous results by Iglesias and Silk. The shock enhancement of HCO + detected in the supernova remnant IC 443 by Dickenson et al. is due to enhanced ionization in the shocked material. This is the result of the material penetrating the remnant cavity where it becomes exposed to the trapped cosmic rays. A similar enhancement appears to have been detected by Wootten in W28 and is explained by the same model

  2. Nonthermal Particles and Radiation Produced by Cluster Merger Shocks

    Science.gov (United States)

    2003-09-10

    NONTHERMAL PARTICLES AND RADIATION PRODUCED BY CLUSTER MERGER SHOCKS Robert C. Berrington and Charles D. Dermer Naval Research Laboratory, Code 7653...of the merging cluster and is assumed to be constant as the shock propagates outward from the cluster center. In this paper , we model the cluster ...emission in the60–250 eV band for a number of clus- ters. These clusters include Virgo , Coma, Fornax, A2199, A1795, and A4059 (Lieu et al. 1996a, 1996b

  3. Shock Isolation Elements Testing for High Input Loadings. Volume II. Foam Shock Isolation Elements.

    Science.gov (United States)

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*EXPANDED PLASTICS, (*SHOCK(MECHANICS), REDUCTION), TEST METHODS, SHOCK WAVES, STRAIN(MECHANICS), LOADS(FORCES), MATHEMATICAL MODELS, NUCLEAR EXPLOSIONS, HARDENING.

  4. Particle acceleration by coronal and interplanetary shock waves

    International Nuclear Information System (INIS)

    Pesses, M.E.

    1982-01-01

    Utilizing many years of observation from deep space and near-earth spacecraft a theoretical understanding has evolved on how ions and electrons are accelerated in interplanetary shock waves. This understanding is now being applied to solar flare-induced shock waves propagating through the solar atmosphere. Such solar flare phenomena as gamma-ray line and neutron emissions, interplanetary energetic electron and ion events, and Type II and moving Type IV radio bursts appear understandable in terms of particle acceleration in shock waves

  5. Emissions Modeling Clearinghouse

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Emissions Modeling Clearinghouse (EMCH) supports and promotes emissions modeling activities both internal and external to the EPA. Through this site, the EPA...

  6. The shock tube as wave reactor for kinetic studies and material systems

    Energy Technology Data Exchange (ETDEWEB)

    Bhaskaran, K.A. [Indian Institute of Technology, Chennai (India). Department of Mechanical Engineering; Roth, P. [Gerhard Mercator Universitat, Duisberg (Germany). Institut fur Verbrennung und Gasdynamik

    2002-07-01

    Several important reviews of shock tube kinetics have appeared earlier, prominent among them being 'Shock Tube Technique in Chemical Kinetics' by Belford and Strehlow (Ann Rev Phys Chem 20 (1969) 247), 'Chemical Reaction of Shock Waves' by Wagner (Proceedings of the Eighth International Shock Tube Symposium (1971) 4/1), 'Shock Tube and Shock Wave Research' by Bauer and Lewis (Proceedings of the 11th International Symposium on Shock Tubes and Waves (1977) 269), 'Shock Waves in Chemistry' edited by Assa Lifshitz (Shock Waves in Chemistry, 1981) and 'Shock Tube Techniques in Chemical Kinetics' by Wing Tsang and Assa Lifshitz (Annu Rev Phys Chem 41 (1990) 559). A critical analysis of the different shock tube techniques, their limitations and suggestions to improve the accuracy of the data produced are contained in these reviews. The purpose of this article is to present the current status of kinetic research with emphasis on the diagnostic techniques. Selected studies on homogeneous and dispersed systems are presented to bring out the versatility of the shock tube technique. The use of the shock tube as high temperature wave reactor for gas phase material synthesis is also highlighted. (author)

  7. OBSERVATIONAL SIGNATURES OF SUB-PHOTOSPHERIC RADIATION-MEDIATED SHOCKS IN THE PROMPT PHASE OF GAMMA-RAY BURSTS

    International Nuclear Information System (INIS)

    Levinson, Amir

    2012-01-01

    A shock that forms below the photosphere of a gamma-ray burst (GRB) outflow is mediated by Compton scattering of radiation advected into the shock by the upstream fluid. The characteristic scale of such a shock, a few Thomson depths, is larger than any kinetic scale involved by several orders of magnitude. Hence, unlike collisionless shocks, radiation-mediated shocks cannot accelerate particles to nonthermal energies. The spectrum emitted by a shock that emerges from the photosphere of a GRB jet reflects the temperature profile downstream of the shock, with a possible contribution at the highest energies from the shock transition layer itself. We study the properties of radiation-mediated shocks that form during the prompt phase of GRBs and compute the time-integrated spectrum emitted by the shocked fluid following shock breakout. We show that the time-integrated emission from a single shock exhibits a prominent thermal peak, with the location of the peak depending on the shock velocity profile. We also point out that multiple shock emission can produce a spectrum that mimics a Band spectrum.

  8. Counseling For Future Shock

    Science.gov (United States)

    Morgan, Lewis B.

    1974-01-01

    In this article the author looks at some of the searing prophecies made by Alvin Toffler in his book Future Shock and relates them to the world of the professional counselor and the clientele the counselor attempts to serve. (Author)

  9. Life shocks and homelessness.

    Science.gov (United States)

    Curtis, Marah A; Corman, Hope; Noonan, Kelly; Reichman, Nancy E

    2013-12-01

    We exploited an exogenous health shock-namely, the birth of a child with a severe health condition-to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide.

  10. Unlimited Relativistic Shock Surfing Acceleration

    International Nuclear Information System (INIS)

    Ucer, D.; Shapiro, V. D.

    2001-01-01

    Nonrelativistic shock surfing acceleration at quasiperpendicular shocks is usually considered to be a preacceleration mechanism for slow pickup ions to initiate diffusive shock acceleration. In shock surfing, the particle accelerates along the shock front under the action of the convective electric field of the plasma flow. However, the particle also gains kinetic energy normal to the shock and eventually escapes downstream. We consider the case when ions are accelerated to relativistic velocities. In this case, the ions are likely to be trapped for infinitely long times, because the energy of bounce oscillations tends to decrease during acceleration. This suggests the possibility of unlimited acceleration by shock surfing

  11. Technology shocks matter

    OpenAIRE

    Jonas D. M. Fisher

    2002-01-01

    This paper uses the neoclassical growth model to identify the effects of technological change on the US business cycle. In the model there are two sources of technological change: neutral, which effects the production of all goods homogeneously, and investment-specific. Investment-specific shocks are the unique source of the secular trend in the real price of investment goods, while shocks to both kinds of technology are the only factors which affect labor productivity in the long run. Consis...

  12. International Emissions Trading and Induced Carbon-Saving Technical Change : Effects of Restricting the Trade in Carbon Rights

    OpenAIRE

    Matschoss, Patrick; Welsch, Heinz

    2004-01-01

    This paper examines the implications of restricting the tradability of carbon rights in the presence of induced technical change. Unlike earlier approaches aiming at exploring the tradability-technology linkage we focus on climate-relevant 'carbon-saving' technical change. This is achieved by incorporating endogenous investment in carbon productivity into the RICE-99 integrated assessment model of Nordhaus and Boyer (2000). Simulation analysis of various emission reduction scenarios with seve...

  13. The Heliospheric Termination Shock

    Science.gov (United States)

    Jokipii, J. R.

    2013-06-01

    The heliospheric termination shock is a vast, spheroidal shock wave marking the transition from the supersonic solar wind to the slower flow in the heliosheath, in response to the pressure of the interstellar medium. It is one of the most-important boundaries in the outer heliosphere. It affects energetic particles strongly and for this reason is a significant factor in the effects of the Sun on Galactic cosmic rays. This paper summarizes the general properties and overall large-scale structure and motions of the termination shock. Observations over the past several years, both in situ and remote, have dramatically revised our understanding of the shock. The consensus now is that the shock is quite blunt, is with the front, blunt side canted at an angle to the flow direction of the local interstellar plasma relative to the Sun, and is dynamical and turbulent. Much of this new understanding has come from remote observations of energetic charged particles interacting with the shock, radio waves and radiation backscattered from interstellar neutral atoms. The observations and the implications are discussed.

  14. The distribution and magnitude of emissions mitigation costs in climate stabilization under less than perfect international cooperation: SGM results

    International Nuclear Information System (INIS)

    Calvin, Katherine; Patel, Pralit; Fawcett, Allen; Clarke, Leon; Fisher-Vanden, Karen; Edmonds, Jae; Kim, Son H.; Sands, Ron; Wise, Marshall

    2009-01-01

    The EMF22 Transition Scenario subgroup explores the implications of delayed accession on limiting climate change to various radiative forcing levels. This paper focuses on the cost of limiting radiative forcing and the role that industrial leakage plays in scenarios of delayed accession. We find that delayed participation shifts the cost burden toward regions that take early action and away from regions that undertake mitigation later. However, the inefficiencies introduced by delay are so great that present discounted costs are higher in the delayed scenario for regions that delay as well as for regions taking early actions. An important element of these inefficiencies is industrial emissions leakage, that is non-participating regions increase their emissions relative to the reference case. In aggregate, industrial leakage rates are less than 10% if all regions of the world begin emissions mitigation by 2050-higher in carbon-intensive sectors and lower in low-carbon-intensity sectors. Additionally, we consider the implication of technology on carbon prices, the feasibility of limiting radiative forcing to low levels, and the incentives to overshoot the radiative forcing limit.

  15. International distortions of competition under emissions trading due to differences in national permit allocation. Theory and empirical analysis of the EU-energy intensive industry

    International Nuclear Information System (INIS)

    Brockhagen, D.

    2004-03-01

    The first part develops a theory of distortions of competition among competing firms, induced by differences in the method and/or stringency of national allocation of greenhouse gas emission permits in an international emissions trading system. By applying neoclassical theory on output optimisation, price setting and other factors such as R and D expenditures, five potentially distorting effects are identified for perfect and imperfect markets,. The second part develops economic indicators and a two tier approach, which can be applied empirically, in order to test whether an industry is vulnerable to the potential effects found before. The third part applies the two tier approach empirically to four sectors of the energy intensive industry in the EU: steel making, cement, oil refining and electricity generation. The steel industry is the most vulnerable industry, followed by oil refining, whereas cement and electricity are not vulnerable. At a permit price of 20 euros/ton CO 2 , and with national allocations that differ more than 40% in terms of allowed emissions per ton product output, this thesis predicts that some steel makers would be forced out of the market. (author)

  16. Best practices and better protocols : guidance for a comprehensive community emissions inventory system from a high level review of international best practices

    International Nuclear Information System (INIS)

    Boston, A.

    2007-11-01

    A community greenhouse gas emission and energy inventory is an important tool to help local governments plan, implement and monitor climate change mitigation strategies and sustainable energy systems. Inventories can also facilitate a number of other local priorities such as air quality management; integrated land-use and transportation planning; infrastructure optimization and planning; and community economic development planning. The British Columbia government's community energy and emissions inventory initiative (CEEI) intends to collect and centralize high-quality geocoded data to generate high-value community inventories for the province's 185 local governments. This report presented strategic guidance for a comprehensive community emissions inventory system based on a high level review of international best practices. The report described the project objective and scope; guiding principles; research methodology; and inventory limitations. The report provided observations, findings and recommendations according to the following four areas: protocols and standards recommendations; data management systems recommendations; community inventory parameters recommendations; and reporting formats and capacity building recommendations. It was recommended that as CEEI progresses, consideration should be given to developing provincial level reports and online reporting of local government activity in order to strengthen awareness, recognize leadership and build support.17 refs., 2 tabs., 11 figs., 2 appendices

  17. A link between prompt optical and prompt gamma-ray emission in gamma-ray bursts.

    Science.gov (United States)

    Vestrand, W T; Wozniak, P R; Wren, J A; Fenimore, E E; Sakamoto, T; White, R R; Casperson, D; Davis, H; Evans, S; Galassi, M; McGowan, K E; Schier, J A; Asa, J W; Barthelmy, S D; Cummings, J R; Gehrels, N; Hullinger, D; Krimm, H A; Markwardt, C B; McLean, K; Palmer, D; Parsons, A; Tueller, J

    2005-05-12

    The prompt optical emission that arrives with the gamma-rays from a cosmic gamma-ray burst (GRB) is a signature of the engine powering the burst, the properties of the ultra-relativistic ejecta of the explosion, and the ejecta's interactions with the surroundings. Until now, only GRB 990123 had been detected at optical wavelengths during the burst phase. Its prompt optical emission was variable and uncorrelated with the prompt gamma-ray emission, suggesting that the optical emission was generated by a reverse shock arising from the ejecta's collision with surrounding material. Here we report prompt optical emission from GRB 041219a. It is variable and correlated with the prompt gamma-rays, indicating a common origin for the optical light and the gamma-rays. Within the context of the standard fireball model of GRBs, we attribute this new optical component to internal shocks driven into the burst ejecta by variations of the inner engine. The correlated optical emission is a direct probe of the jet isolated from the medium. The timing of the uncorrelated optical emission is strongly dependent on the nature of the medium.

  18. Summary of the presentations at the international workshop on reducing carbon dioxide emissions from the developing world: Assessment of benefits, costs and barriers

    International Nuclear Information System (INIS)

    Sathaye, J.; Goldman, N.

    1991-06-01

    The ''International Workshop on Reducing Carbon Dioxide Emissions from the Developing World: Assessment of Benefits, Costs and Barriers'' was the second workshop held as part of a project being conducted by the International Energy Studies Group of Lawrence Berkeley Laboratory, in collaboration with experts from leading institutions across the developing world. The goal of the project is to analyze long-range energy consumption in developing countries and its potential contribution to global climate change. The US Environmental Protection Agency (EPA) is supporting this work, the results of which already have made a key contribution to the technical analysis being used as the basis for discussion by the Energy and Industry Sub-group of the Intergovernmental Panel on Climate Change (IPCC). The main purpose of this workshop was two-fold: (1) to discuss the feasibility of implementing the efficiency improvements and fuel switching measures incorporated into the long-term energy scenarios created for 17 developing countries and (2) to examine the costs and benefits of reducing energy-related carbon dioxide emissions generated by developing countries

  19. Curved Radio Spectra of Weak Cluster Shocks

    Science.gov (United States)

    Kang, Hyesung; Ryu, Dongsu

    2015-08-01

    In order to understand certain observed features of arc-like giant radio relics such as the rareness, uniform surface brightness, and curved integrated spectra, we explore a diffusive shock acceleration (DSA) model for radio relics in which a spherical shock impinges on a magnetized cloud containing fossil relativistic electrons. Toward this end, we perform DSA simulations of spherical shocks with the parameters relevant for the Sausage radio relic in cluster CIZA J2242.8+5301, and calculate the ensuing radio synchrotron emission from re-accelerated electrons. Three types of fossil electron populations are considered: a delta-function like population with the shock injection momentum, a power-law distribution, and a power law with an exponential cutoff. The surface brightness profile of the radio-emitting postshock region and the volume-integrated radio spectrum are calculated and compared with observations. We find that the observed width of the Sausage relic can be explained reasonably well by shocks with speed {u}{{s}}˜ 3× {10}3 {km} {{{s}}}-1 and sonic Mach number {M}{{s}}˜ 3. These shocks produce curved radio spectra that steepen gradually over (0.1-10){ν }{br} with a break frequency {ν }{br}˜ 1 GHz if the duration of electron acceleration is ˜60-80 Myr. However, the abrupt increase in the spectral index above ˜1.5 GHz observed in the Sausage relic seems to indicate that additional physical processes, other than radiative losses, operate for electrons with {γ }{{e}}≳ {10}4.

  20. Diagnosing radiative shocks from deuterium and tritium implosions on NIF.

    Science.gov (United States)

    Pak, A; Divol, L; Weber, S; Döppner, T; Kyrala, G A; Kilne, J; Izumi, N; Glenn, S; Ma, T; Town, R P; Bradley, D K; Glenzer, S H

    2012-10-01

    During the recent ignition tuning campaign at the National Ignition Facility, layered cryogenic deuterium and tritium capsules were imploded via x-ray driven ablation. The hardened gated x-ray imager diagnostic temporally and spatially resolves the x-ray emission from the core of the capsule implosion at energies above ~8 keV. On multiple implosions, ~200-400 ps after peak compression a spherically expanding radiative shock has been observed. This paper describes the methods used to characterize the radial profile and rate of expansion of the shock induced x-ray emission.

  1. IRS SCAN-MAPPING OF THE WASP-WAIST NEBULA (IRAS 16253-2429). I. DERIVATION OF SHOCK CONDITIONS FROM H2 EMISSION AND DISCOVERY OF 11.3 μm PAH ABSORPTION

    International Nuclear Information System (INIS)

    Barsony, Mary; Wolf-Chase, Grace A.; Ciardi, David R.; O'Linger, JoAnn

    2010-01-01

    The outflow driven by the Class 0 protostar, IRAS 16253-2429, is associated with bipolar cavities visible in scattered mid-infrared light, which we refer to as the Wasp-Waist Nebula. InfraRed Spectometer (IRS) scan mapping with the Spitzer Space Telescope of a ∼1' x 2' area centered on the protostar was carried out. The outflow is imaged in six pure rotational (0-0 S(2) through 0-0 S(7)) H 2 lines, revealing a distinct, S-shaped morphology in all maps. A source map in the 11.3 μm polycyclic aromatic hydrocarbon (PAH) feature is presented in which the protostellar envelope appears in absorption. This is the first detection of absorption in the 11.3 μm PAH feature. Spatially resolved excitation analysis of positions in the blue- and redshifted outflow lobes, with extinction-corrections determined from archival Spitzer 8 μm imaging, shows remarkably constant temperatures of ∼1000 K in the shocked gas. The radiated luminosity in the observed H 2 transitions is found to be 1.94 ± 0.05 x 10 -5 L sun in the redshifted lobe and 1.86 ± 0.04 x 10 -5 L sun in the blueshifted lobe. These values are comparable to the mechanical luminosity of the flow. By contrast, the mass of hot (T ∼ 1000 K) H 2 gas is 7.95 ± 0.19 x 10 -7 M sun in the redshifted lobe and 5.78 ± 0.17 x 10 -7 M sun in the blueshifted lobe. This is just a tiny fraction, of order 10 -3 , of the gas in the cold (30 K), swept-up gas mass derived from millimeter CO observations. The H 2 ortho/para ratio of 3:1 found at all mapped points in this flow suggests previous passages of shocks through the gas. Comparison of the H 2 data with detailed shock models of Wilgenbus et al. shows the emitting gas is passing through Jump (J-type) shocks. Pre-shock densities of 10 4 cm -3 ≤ n H ≤ 10 5 cm -3 are inferred for the redshifted lobe and n H ≤ 10 3 cm -3 for the blueshifted lobe. Shock velocities are 5 km s -1 ≤ v s ≤ 10 km s -1 for the redshifted gas and v s = 10 km s -1 for the blueshifted gas

  2. Shocks in fragile matter

    Science.gov (United States)

    Vitelli, Vincenzo

    2012-02-01

    Non-linear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they unjam, these fragile and disordered solids exhibit vanishing elastic moduli and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are continuously compressed, and demonstrate that the resulting excitations are strongly nonlinear shocks, rather than linear waves. We capture the full dependence of the shock speed on pressure and compression speed by a surprisingly simple analytical model. We also treat shear shocks within a simplified viscoelastic model of nearly-isostatic random networks comprised of harmonic springs. In this case, anharmonicity does not originate locally from nonlinear interactions between particles, as in granular media; instead, it emerges from the global architecture of the network. As a result, the diverging width of the shear shocks bears a nonlinear signature of the diverging isostatic length associated with the loss of rigidity in these floppy networks.

  3. True versus apparent shapes of bow shocks

    Science.gov (United States)

    Tarango-Yong, Jorge A.; Henney, William J.

    2018-06-01

    Astrophysical bow shocks are a common result of the interaction between two supersonic plasma flows, such as winds or jets from stars or active galaxies, or streams due to the relative motion between a star and the interstellar medium. For cylindrically symmetric bow shocks, we develop a general theory for the effects of inclination angle on the apparent shape. We propose a new two-dimensional classification scheme for bow shapes, which is based on dimensionless geometric ratios that can be estimated from observational images. The two ratios are related to the flatness of the bow's apex, which we term planitude, and the openness of its wings, which we term alatude. We calculate the expected distribution in the planitude-alatude plane for a variety of simple geometrical and physical models: quadrics of revolution, wilkinoids, cantoids, and ancantoids. We further test our methods against numerical magnetohydrodynamical simulations of stellar bow shocks and find that the apparent planitude and alatude measured from infrared dust continuum maps serve as accurate diagnostics of the shape of the contact discontinuity, which can be used to discriminate between different physical models. We present an algorithm that can determine the planitude and alatude from observed bow shock emission maps with a precision of 10 to 20 per cent.

  4. SHOCKED SUPERWINDS FROM THE z {approx} 2 CLUMPY STAR-FORMING GALAXY, ZC406690

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Sarah F.; Genzel, Reinhard [Department of Astronomy, Campbell Hall, University of California, Berkeley, CA 94720 (United States); Shapiro Griffin, Kristen [Aerospace Research Laboratories, Northrop Grumman Aerospace Systems, Redondo Beach, CA 90278 (United States); Davies, Ric; Foerster-Schreiber, Natascha M.; Tacconi, Linda J.; Kurk, Jaron; Wuyts, Stijn; Genel, Shy; Buschkamp, Peter; Eisenhauer, Frank; Lutz, Dieter [Max-Planck-Institut fuer extraterrestrische Physik (MPE), Giessenbachstr.1, D-85748 Garching (Germany); Lilly, Simon J.; Carollo, C. Marcella [Institute of Astronomy, Department of Physics, Eidgenoessische Technische Hochschule, ETH Zuerich CH-8093 (Switzerland); Renzini, Alvio; Mancini, Chiara [Osservatorio Astronomico di Padova, Vicolo dellOsservatorio 5, Padova I-35122 (Italy); Bouche, Nicolas [Department of Physics and Astronomy, University of California, Santa Barbara, Santa Barbara, CA 93106 (United States); Burkert, Andreas [Department fuer Physik, Universitaets-Sternwarte Ludwig-Maximilians-Universitaet (USM), Scheinerstr. 1, Muenchen, D-81679 (Germany); Cresci, Giovanni [Istituto Nazionale di AstrofisicaOsservatorio Astronomico di Arcetri, Largo Enrico Fermi 5, I 50125 Firenze (Italy); Hicks, Erin, E-mail: sfnewman@berkeley.edu [Department of Astronomy, University of Washington, Box 351580, U.W., Seattle, WA 98195-1580 (United States); and others

    2012-06-20

    We have obtained high-resolution data of the z {approx} 2 ring-like, clumpy star-forming galaxy (SFG) ZC406690 using the VLT/SINFONI with adaptive optics (in K band) and in seeing-limited mode (in H and J bands). Our data include all of the main strong optical emission lines: [O II], [O III], H{alpha}, H{beta}, [N II], and [S II]. We find broad, blueshifted H{alpha} and [O III] emission line wings in the spectra of the galaxy's massive, star-forming clumps ({sigma} {approx} 85 km s{sup -1}) and even broader wings (up to 70% of the total H{alpha} flux, with {sigma} {approx} 290 km s{sup -1}) in regions spatially offset from the clumps by {approx}2 kpc. The broad emission likely originates from large-scale outflows with mass outflow rates from individual clumps that are 1-8 Multiplication-Sign the star formation rate (SFR) of the clumps. Based on emission line ratio diagnostics ([N II]/H{alpha} and [S II]/H{alpha}) and photoionization and shock models, we find that the emission from the clumps is due to a combination of photoionization from the star-forming regions and shocks generated in the outflowing component, with 5%-30% of the emission deriving from shocks. In terms of the ionization parameter (6 Multiplication-Sign 10{sup 7} to 10{sup 8} cm s{sup -1}, based on both the SFR and the O{sub 32} ratio), density (local electron densities of 300-1800 cm{sup -3} in and around the clumps, and ionized gas column densities of 1200-8000 M{sub Sun }pc{sup -2}), and SFR (10-40 M{sub Sun} yr{sup -1}), these clumps more closely resemble nuclear starburst regions of local ultraluminous infrared galaxies and dwarf irregulars than H II regions in local galaxies. However, the star-forming clumps are not located in the nucleus as in local starburst galaxies but instead are situated in a ring several kpc from the center of their high-redshift host galaxy, and have an overall disk-like morphology. The two brightest clumps are quite different in terms of their internal

  5. Modeling of secondary emission processes in the negative ion based electrostatic accelerator of the International Thermonuclear Experimental Reactor

    OpenAIRE

    G. Fubiani; H. P. L. de Esch; A. Simonin; R. S. Hemsworth

    2008-01-01

    The negative ion electrostatic accelerator for the neutral beam injector of the International Thermonuclear Experimental Reactor (ITER) is designed to deliver a negative deuterium current of 40 A at 1 MeV. Inside the accelerator there are several types of interactions that may create secondary particles. The dominating process originates from the single and double stripping of the accelerated negative ion by collision with the residual molecular deuterium gas (≃29% losses). The resulting seco...

  6. Physics of Collisionless Shocks Space Plasma Shock Waves

    CERN Document Server

    Balogh, André

    2013-01-01

    The present book provides a contemporary systematic treatment of shock waves in high-temperature collisionless plasmas as are encountered in near Earth space and in Astrophysics. It consists of two parts. Part I develops the complete theory of shocks in dilute hot plasmas under the assumption of absence of collisions among the charged particles when the interaction is mediated solely by the self-consistent electromagnetic fields. Such shocks are naturally magnetised implying that the magnetic field plays an important role in their evolution and dynamics. This part treats both subcritical shocks, which dissipate flow energy by generating anomalous resistance or viscosity, and supercritical shocks. The main emphasis is, however, on super-critical shocks where the anomalous dissipation is insufficient to retard the upstream flow. These shocks, depending on the direction of the upstream magnetic field, are distinguished as quasi-perpendicular and quasi-parallel shocks which exhibit different behaviours, reflecti...

  7. Life Shocks and Homelessness

    Science.gov (United States)

    Corman, Hope; Noonan, Kelly; Reichman, Nancy E.

    2014-01-01

    We exploited an exogenous health shock—namely, the birth of a child with a severe health condition—to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide. PMID:23868747

  8. Health Shocks and Retirement:

    DEFF Research Database (Denmark)

    Datta Gupta, Nabanita; Larsen, Mona

    We investigate the effect of an acute health shock on retirement among elderly male workers in Denmark, 1991-1999, and in particular whether various welfare state programs and institutions impinge on the retirement effect. The results show that an acute health event increases the retirement chances...... significant. For the most part, the retirement effect following a health shock seems to be immune to the availability of a multitude of government programs for older workers in Denmark....... benefits in Denmark nor by the promotion of corporate social responsibility initiatives since the mid-1990s. In the late 1990s, however, the retirement rate following a health shock is reduced to 3% with the introduction of the subsidized employment program (fleksjob) but this effect is not strongly...

  9. Electron beams by shock waves in the solar corona

    International Nuclear Information System (INIS)

    Mann, G.; Klassen, A.

    2005-07-01

    Beams of energetic electrons can be generated by shock waves in the solar corona. At the Sun shock waves are produced either by flares and/or by coronal mass ejections (CMEs). They can be observed as type II bursts in the solar radio radiation. Shock accelerated electron beams appear as rapidly drifting emission stripes (so-called ''herringbones'') in dynamic radio spectra of type II bursts. A large sample of type II bursts showing ''herringbones'' was statistically analysed with respect to their properties in dynamic radio spectra. The electron beams associated with the ''herringbones'' are considered to be generated by shock drift acceleration. Then, the accelerated electrons establish a shifted loss-cone distribution in the upstream region of the associated shock wave. Such a distribution causes plasma instabilities leading to the emission of radio waves observed as ''herringbones''. Consequences of a shifted loss-cone distribution of the shock accelerated electrons are discussed in comparison with the observations of ''herringbones'' within solar type II radio bursts. (orig.)

  10. The Shock Routine

    DEFF Research Database (Denmark)

    van Hooren, Franca; Kaasch, Alexandra; Starke, Peter

    2014-01-01

    in Australia, Belgium, the Netherlands and Sweden over the course of four global economic shocks, we ask whether the notion of critical junctures is useful in understanding the nature of change triggered by crisis. The main empirical finding is that fundamental change in the aftermath of an exogenous shock...... is the exception rather than the rule. Instead, incremental ‘crisis routines’ based on existing policy instruments are overwhelmingly used to deal with economic hardship. We discuss these findings in the light of the psychological ‘threat-rigidity’ effect and reflect on their consequences for theories...

  11. Shockingly low water abundances in Herschel/PACS observations of low-mass protostars in Perseus

    DEFF Research Database (Denmark)

    Karska, A.; Kristensen, L. E.; Dishoeck, E. F. van

    2014-01-01

    Protostars interact with their surroundings through jets and winds impacting on the envelope and creating shocks, but the nature of these shocks is still poorly understood. Our aim is to survey far-infrared molecular line emission from a uniform and significant sample of deeply-embedded low...

  12. THE EVOLUTION OF MOLECULAR LINE PROFILES INDUCED BY THE PROPAGATION OF C-SHOCK WAVES

    International Nuclear Information System (INIS)

    Jimenez-Serra, I.; Caselli, P.; Martin-Pintado, J.; RodrIguez-Franco, A.; Viti, S.

    2009-01-01

    We present the first results of the expected variations of the molecular line emission arising from material recently affected by C-shocks (shock precursors). Our parametric model of the structure of C-shocks has been coupled with a radiative transfer code to calculate the molecular excitation and line profiles of shock tracers such as SiO, and of ion and neutral molecules such as H 13 CO + and HN 13 C, as the shock propagates through the unperturbed medium. Our results show that the SiO emission arising from the early stage of the magnetic precursor typically has very narrow line profiles slightly shifted in velocity with respect to the ambient cloud. This narrow emission is generated in the region where the bulk of the ion fluid has already slipped to larger velocities in the precursor as observed toward the young L1448-mm outflow. This strongly suggests that the detection of narrow SiO emission, and of an ion enhancement in young shocks, is produced by the magnetic precursor of C-shocks. In addition, our model shows that the different velocity components observed toward this outflow can be explained by the coexistence of different shocks at different evolutionary stages, within the same beam of the single-dish observations.

  13. On the stability of bow shocks generated by red supergiants: the case of IRC -10414

    Science.gov (United States)

    Meyer, D. M.-A.; Gvaramadze, V. V.; Langer, N.; Mackey, J.; Boumis, P.; Mohamed, S.

    2014-03-01

    In this Letter, we explore the hypothesis that the smooth appearance of bow shocks around some red supergiants (RSGs) might be caused by the ionization of their winds by external sources of radiation. Our numerical simulations of the bow shock generated by IRC -10414 (the first-ever RSG with an optically detected bow shock) show that the ionization of the wind results in its acceleration by a factor of 2, which reduces the difference between the wind and space velocities of the star and makes the contact discontinuity of the bow shock stable for a range of stellar space velocities and mass-loss rates. Our best-fitting model reproduces the overall shape and surface brightness of the observed bow shock and suggests that the space velocity and mass-loss rate of IRC -10414 are ≈50 km s-1 and ≈10-6 M⊙ yr-1, respectively, and that the number density of the local interstellar medium is ≈3 cm-3. It also shows that the bow shock emission comes mainly from the shocked stellar wind. This naturally explains the enhanced nitrogen abundance in the line-emitting material, derived from the spectroscopy of the bow shock. We found that photoionized bow shocks are ≈15-50 times brighter in optical line emission than their neutral counterparts, from which we conclude that the bow shock of IRC -10414 must be photoionized.

  14. Two-stream instability in collisionless shocks and foreshock

    International Nuclear Information System (INIS)

    Dieckmann, M E; Eliasson, B; Shukla, P K; Sircombe, N J; Dendy, R O

    2006-01-01

    Shocks play a key role in plasma thermalization and particle acceleration in the near Earth space plasma, in astrophysical plasma and in laser plasma interactions. An accurate understanding of the physics of plasma shocks is thus of immense importance. We give an overview over some recent developments in particle-in-cell simulations of plasma shocks and foreshock dynamics. We focus on ion reflection by shocks and on the two-stream instabilities these beams can drive, and these are placed in the context of experimental observations, e.g. by the Cluster mission. We discuss how we may expand the insight gained from the observation of proton beam driven instabilities at near Earth plasma shocks to better understand their astrophysical counterparts, such as ion beam instabilities triggered by internal and external shocks in the relativistic jets of gamma ray bursts, shocks in the accretion discs of micro-quasars and supernova remnant shocks. It is discussed how and why the peak energy that can be reached by particles that are accelerated by two-stream instabilities increases from keV energies to GeV energies and beyond, as we increase the streaming speed to relativistic values, and why the particle energy spectrum sometimes resembles power law distributions

  15. Two-stream instability in collisionless shocks and foreshock

    Energy Technology Data Exchange (ETDEWEB)

    Dieckmann, M E [Institute of Theoretical Physics IV and Centre for Plasma Science and Astrophysics, Ruhr-University Bochum, D-44780 Bochum (Germany); Eliasson, B [Institute of Theoretical Physics IV and Centre for Plasma Science and Astrophysics, Ruhr-University Bochum, D-44780 Bochum (Germany); Shukla, P K [Institute of Theoretical Physics IV and Centre for Plasma Science and Astrophysics, Ruhr-University Bochum, D-44780 Bochum (Germany); Sircombe, N J [Centre for Fusion, Space and Astrophysics, Department of Physics, Warwick University, Coventry CV4 7AL (United Kingdom); Dendy, R O [Centre for Fusion, Space and Astrophysics, Department of Physics, Warwick University, Coventry CV4 7AL (United Kingdom)

    2006-12-15

    Shocks play a key role in plasma thermalization and particle acceleration in the near Earth space plasma, in astrophysical plasma and in laser plasma interactions. An accurate understanding of the physics of plasma shocks is thus of immense importance. We give an overview over some recent developments in particle-in-cell simulations of plasma shocks and foreshock dynamics. We focus on ion reflection by shocks and on the two-stream instabilities these beams can drive, and these are placed in the context of experimental observations, e.g. by the Cluster mission. We discuss how we may expand the insight gained from the observation of proton beam driven instabilities at near Earth plasma shocks to better understand their astrophysical counterparts, such as ion beam instabilities triggered by internal and external shocks in the relativistic jets of gamma ray bursts, shocks in the accretion discs of micro-quasars and supernova remnant shocks. It is discussed how and why the peak energy that can be reached by particles that are accelerated by two-stream instabilities increases from keV energies to GeV energies and beyond, as we increase the streaming speed to relativistic values, and why the particle energy spectrum sometimes resembles power law distributions.

  16. The PolicyRelevance of WearEmissions fromRoad Transport,Nowand in the Future-An InternationalWorkshop Report and Consensus Statement

    NARCIS (Netherlands)

    Denier van der Gon, H.A.C.; Gerlofs-Nijland, M.E.; Gehrig, R.; Gustafsson, M.; Janssen, N.; Harrison, R.M.; Hulskotte, J.; Johansson, C.; Jozwicka, M.; Keuken, M.; Krijgsheld, K.; Ntziachristos, L.; Riediker, M.; Cassee, F.R.

    2013-01-01

    Road transport emissions are a major contributor to ambient particulate matter concentrations and have been associated with adverse health effects. Therefore, these emissions are targeted through increasingly stringent European emission standards. These policies succeed in reducing exhaust

  17. Shock absorber in Ignalina NPP

    International Nuclear Information System (INIS)

    Bulavas, A.; Muralis, J.

    1996-09-01

    Theoretical calculation and experimental analysis of models of shock absorber in Ignalina NPP is presented. The results obtained from the investigation with model of shock absorber coincide with the theoretical calculation. (author). 2 figs., 3 refs

  18. Shock Response of Boron Carbide

    National Research Council Canada - National Science Library

    Dandekar, D. P. (Dattatraya Purushottam)

    2001-01-01

    .... The present work was undertaken to determine tensile/spall strength of boron carbide under plane shock wave loading and to analyze all available shock compression data on boron carbide materials...

  19. Fascinating World of Shock Waves

    Indian Academy of Sciences (India)

    Srimath

    travelling at supersonic speeds (more than the sound speed at ... actual earth- quake, travel at supersonic speeds. .... The time scale of the shock wave is also important ..... real lithotripsy where a shock wave is used shatter the kidney stones!

  20. What China can learn from international policy experiences to improve industrial energy efficiency and reduce CO2 emissions?

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xu [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shen, Bo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-11-01

    China’s industrial sector dominates the country’s total energy consumption and energy efficiency in the industry sector is crucial to help China reach its energy and CO2 emissions reduction goals. There are many energy efficiency policies in China, but the motivation and willingness of enterprises to improve energy efficiency has weakened. This report first identifies barriers that enterprises face to be self-motivated to implement energy efficiency measures. Then, this report reviews international policies and programs to improve energy efficiency and evaluates how these policies helped to address the identified barriers. Lastly, this report draws conclusions and provides recommendations to China in developing policies and programs to motivate enterprises to improve energy efficiency.

  1. Revealing by secondary electronic emission of internal electric fields in the yttriated zirconia, irradiated by electrons of 1 MeV

    International Nuclear Information System (INIS)

    Blaise, G.; Paris-11 Univ., 91 - Orsay

    2007-01-01

    The defects due to irradiation in a dielectric material present an activity which can generate macroscopic internal electric fields. A method of investigation of these fields, based on the measure of the Secondary Electronic Emission coefficient, has been developed on a scanning electric microscope. This ones contains two low noise detectors which respectively measure the influence current I IC produced by the charges trapping in the material and the current I SB due to secondary and backscattered electrons which come from the sample. The Secondary Emission coefficient is given by σ=I SB /(I SB +I IC ). The charges trapping during an electrons injection leads to a variation of σ for its intrinsic value σ 0 relative to the uncharged material, until the stationary value σ st =1 corresponding to the auto-regulated condition. This variation is due to the development of an internal electric field produced by the accumulation of the charges trapped during injection. In comparing the evolutions of σ of a fresh yttriated zirconia and of an yttriated zirconia irradiated by electrons of 1 MeV with a dose rate of 10 18 e/cm 2 , it has been revealed that an internal field (due to irradiation) of about 0.5*10 6 V/m exists at a depth of the micron order. This field, directed towards the outside of the material surface, is attributed to the F + defects and to the T centers produced by the impact of the electrons of 1 MeV. In carrying out annealings until 1000 K, a progressive disappearance of this field is observed in the temperature range of 400-600 K, directly due to the F + defects and T centers recovery, as it has been observed by ESR. An internal field three times weaker than the preceding ones has been revealed at a few nm under the surface. Its disappearance from a temperature of 1000 K suggests that it is due to the redistribution of the chemical species into the surface, during the irradiation with electrons of 1 MeV. (O.M.)

  2. Probing Shocks of the Young Planetary Nebula NGC 7027

    Science.gov (United States)

    Montez, Rodolfo

    2013-09-01

    The rapid evolution of the planetary nebula NGC 7027 provides a rare glimpse at the evolution of the shocks. We propose a detailed spatial and spectroscopic study of the shock conditions in NGC 7027 that will enhance and bridge our understanding of the shocks seen in other planetary nebula. Comparison between the Cycle 1 observation and a new Cycle 15 observation will (i) confirm the presence of the two components in the extended X-ray emission, (ii) measure the changes (spatial and spectral) in the components, and, (iii) provide a valuable trove of tests and inputs for shock conditions and hydrodynamical simulations. We rely on the unprecedented spatial resolution and soft-sensitivity of Chandra.

  3. Air box shock absorber for a nuclear reactor

    International Nuclear Information System (INIS)

    Pradhan, A.V.; George, J.A.

    1977-01-01

    Disclosed is an air box type shock absorber primarily for use in an ice condenser compartment of a nuclear reactor. The shock absorber includes a back plate member and sheet metal top, bottom, and front members. The front member is prefolded, and controlled clearances are provided among the members for predetermined escape of air under impact and compression. Prefolded internal sheet metal stiffeners also absorb a portion of the kinetic energy imparted to the shock absorber, and limit rebound. An external restraining rod guided by restraining straps insures that the sheet metal front member compresses inward upon impact. 6 claims, 11 figures

  4. Shock wave equation of state of powder material

    OpenAIRE

    Dijken, D.K.; Hosson, J.Th.M. De

    1994-01-01

    A model is proposed to predict the following quantities for powder materials compacted by shock waves: the pressure, the specific volume, the internal energy behind the shock wave, and the shock-wave velocity U-s. They are calculated as a function of flyerplate velocity u(p) and initial powder specific volume V-00. The model is tested on Cu, Al2024, and Fe. Calculated U-s vs u(p) curves agree well with experiments provided V-00 is smaller than about two times the solid specific volume. The mo...

  5. Effects of aeration and internal recycle flow on nitrous oxide emissions from a modified Ludzak-Ettinger process fed with glycerol.

    Science.gov (United States)

    Song, Kang; Suenaga, Toshikazu; Harper, Willie F; Hori, Tomoyuki; Riya, Shohei; Hosomi, Masaaki; Terada, Akihiko

    2015-12-01

    Nitrous oxide (N2O) is emitted from a modified Ludzak-Ettinger (MLE) process, as a primary activated sludge system, which requires mitigation. The effects of aeration rates and internal recycle flow (IRF) ratios on N2O emission were investigated in an MLE process fed with glycerol. Reducing the aeration rate from 1.5 to 0.5 L/min increased gaseous the N2O concentration from the aerobic tank and the dissolved N2O concentration in the anoxic tank by 54.4 and 53.4 %, respectively. During the period of higher aeration, the N2O-N conversion ratio was 0.9 % and the potential N2O reducers were predominantly Rhodobacter, which accounted for 21.8 % of the total population. Increasing the IRF ratio from 3.6 to 7.2 decreased the N2O emission rate from the aerobic tank and the dissolved N2O concentration in the anoxic tank by 56 and 48 %, respectively. This study suggests effective N2O mitigation strategies for MLE systems.

  6. Exogenous shocks and governing energy security

    OpenAIRE

    Diriöz, Ali Oğuz

    2017-01-01

    Cataloged from PDF version of article. Thesis (Ph.D.): Bilkent University, Department of International Relations, İhsan Doğramacı Bilkent University, 2017. Includes bibliographical references (leaves 219-248). The research examines how governments maintain energy security when faced with exogenous shocks. The main focus of inquiry examines the relative influence of markets vs. geopolitics in the area of energy security using the comparative case studies of Turkey, France, and Netherl...

  7. INTERFERENCE OF UNIDIRECTIONAL SHOCK WAVES

    Directory of Open Access Journals (Sweden)

    P. V. Bulat

    2015-05-01

    Full Text Available Subject of study.We consider interference of unidirectional shock waves or, as they are called, catching up shock waves. The scope of work is to give a classification of the shock-wave structures that arise in this type of interaction of shock waves, and the area of their existence. Intersection of unidirectional shock waves results in arising of a shock-wave structure at the intersection point, which contains the main shock wave, tangential discontinuity and one more reflected gas-dynamic discontinuity of unknown beforehand type. The problem of determining the type of reflected discontinuity is the main problem that one has to solve in the study of catching shock waves interference. Main results.The paper presents the pictures of shock-wave structures arising at the interaction of catching up shock waves. The areas with a regular and irregular unidirectional interaction of shocks are described. Characteristic shock-wave structures are of greatest interest, where reflected gas-dynamic discontinuity degenerates into discontinuous characteristics. Such structures have a number of extreme properties. We have found the areas of existence for such shock-wave structures. There are also areas in which the steady-state solution is not available. The latter has determined revival of interest for the theoretical study of the problem, because the facts of sudden shock-wave structure destruction inside the air intake of supersonic aircrafts at high Mach numbers have been discovered. Practical significance.The theory of interference for unidirectional shock waves and design procedure are usable in the design of supersonic air intakes. It is also relevant for application possibility investigation of catching up oblique shock waves to create overcompressed detonation in perspective detonation air-jet and rocket engines.

  8. Center for Environmental Information's Ninth International Conference on Global Energy Strategies : Living with Restricted Greenhouse Gas Emissions

    CERN Document Server

    1993-01-01

    The world is getting warmer. Among scientists concerned with global climate change this is the broad consensus. How fast and by how much, are questions which cannot be answered quantitatively, but the probability of rising temperatures must be faced in a prudent manner - there is enough certainty of change so that we must anticipate and prepare before irreparable damage is done to our world. Even if it isn't going to be as bad as some people think, the actions we propose will benefit the earth and give us a kind of insurance. The root of the change is population growth, and its attendant demand for energy. While the developed world expects to hold future emissions relatively steady, the developing countries, where population growth is most rampant, will expand the use of energy as they aspire to a better quality of life. H greater energy use is inevitable it behooves us to produce that energy in the least objectionable manner, and to produce it where the cost is lowest in dollars, GNP, and environmental chang...

  9. Time development of a blast wave with shock heated electrons

    International Nuclear Information System (INIS)

    Edgar, R.J.; Cox, D.P.

    1983-01-01

    Accurate approximations are presented for the time development of both edge conditions and internal structures of a blast wave with shock heated electrons, and equal ion and electron temperatures at the shock. The cases considered evolve in cavities with power law ambient densities (including the uniform ambient density case) and have negligible external pressure. Account is taken of possible saturation of the thermal conduction flux. The structures evolve smoothly to the adiabatic structures

  10. Shock tube Multiphase Experiments

    Science.gov (United States)

    Middlebrooks, John; Allen, Roy; Paudel, Manoj; Young, Calvin; Musick, Ben; McFarland, Jacob

    2017-11-01

    Shock driven multiphase instabilities (SDMI) are unique physical phenomena that have far-reaching practical applications in engineering and science. The instability is present in high energy explosions, scramjet combustors, and supernovae events. The SDMI arises when a multiphase interface is impulsively accelerated by the passage of a shockwave. It is similar in development to the Richtmyer-Meshkov (RM) instability however, particle-to-gas coupling is the driving mechanism of the SDMI. As particle effects such as lag and phase change become more prominent, the SDMI's development begins to significantly deviate from the RM instability. We have developed an experiment for studying the SDMI in our shock tube facility. In our experiments, a multiphase interface is created using a laminar jet and flowed into the shock tube where it is accelerated by the passage of a planar shockwave. The interface development is captured using CCD cameras synchronized with planar laser illumination. This talk will give an overview of new experiments conducted to examine the development of a shocked cylindrical multiphase interface. The effects of Atwood number, particle size, and a second acceleration (reshock) of the interface will be discussed.

  11. Teleconnected food supply shocks

    Science.gov (United States)

    Bren d'Amour, Christopher; Wenz, Leonie; Kalkuhl, Matthias; Steckel, Jan Christoph; Creutzig, Felix

    2016-03-01

    The 2008-2010 food crisis might have been a harbinger of fundamental climate-induced food crises with geopolitical implications. Heat-wave-induced yield losses in Russia and resulting export restrictions led to increases in market prices for wheat across the Middle East, likely contributing to the Arab Spring. With ongoing climate change, temperatures and temperature variability will rise, leading to higher uncertainty in yields for major nutritional crops. Here we investigate which countries are most vulnerable to teleconnected supply-shocks, i.e. where diets strongly rely on the import of wheat, maize, or rice, and where a large share of the population is living in poverty. We find that the Middle East is most sensitive to teleconnected supply shocks in wheat, Central America to supply shocks in maize, and Western Africa to supply shocks in rice. Weighing with poverty levels, Sub-Saharan Africa is most affected. Altogether, a simultaneous 10% reduction in exports of wheat, rice, and maize would reduce caloric intake of 55 million people living in poverty by about 5%. Export bans in major producing regions would put up to 200 million people below the poverty line at risk, 90% of which live in Sub-Saharan Africa. Our results suggest that a region-specific combination of national increases in agricultural productivity and diversification of trade partners and diets can effectively decrease future food security risks.

  12. STEREO interplanetary shocks and foreshocks

    International Nuclear Information System (INIS)

    Blanco-Cano, X.; Kajdič, P.; Aguilar-Rodríguez, E.; Russell, C. T.; Jian, L. K.; Luhmann, J. G.

    2013-01-01

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and θ Bn ∼20-86°. We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr ≤0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at ∼1 AU and have been producing suprathermal particles for a shorter time.

  13. STEREO interplanetary shocks and foreshocks

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Cano, X. [Instituto de Geofisica, UNAM, CU, Coyoacan 04510 DF (Mexico); Kajdic, P. [IRAP-University of Toulouse, CNRS, Toulouse (France); Aguilar-Rodriguez, E. [Instituto de Geofisica, UNAM, Morelia (Mexico); Russell, C. T. [ESS and IGPP, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095 (United States); Jian, L. K. [NASA Goddard Space Flight Center, Greenbelt, MD and University of Maryland, College Park, MD (United States); Luhmann, J. G. [SSL, University of California Berkeley (United States)

    2013-06-13

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and {theta}{sub Bn}{approx}20-86 Degree-Sign . We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr {<=}0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at {approx}1 AU and have been producing suprathermal particles for a shorter time.

  14. IRC -10414: a bow-shock-producing red supergiant star

    Science.gov (United States)

    Gvaramadze, V. V.; Menten, K. M.; Kniazev, A. Y.; Langer, N.; Mackey, J.; Kraus, A.; Meyer, D. M.-A.; Kamiński, T.

    2014-01-01

    Most runaway OB stars, like the majority of massive stars residing in their parent clusters, go through the red supergiant (RSG) phase during their lifetimes. Nonetheless, although many dozens of massive runaways were found to be associated with bow shocks, only two RSG bow-shock-producing stars, Betelgeuse and μ Cep, are known to date. In this paper, we report the discovery of an arc-like nebula around the late M-type star IRC -10414 using the SuperCOSMOS H-alpha Survey. Our spectroscopic follow-up of IRC -10414 with the Southern African Large Telescope (SALT) showed that it is a M7 supergiant, which supports previous claims on the RSG nature of this star based on observations of its maser emission. This was reinforced by our new radio- and (sub)millimetre-wavelength molecular line observations made with the Atacama Pathfinder Experiment 12-m telescope and the Effelsberg 100-m radio telescope, respectively. The SALT spectrum of the nebula indicates that its emission is the result of shock excitation. This finding along with the arc-like shape of the nebula and an estimate of the space velocity of IRC -10414 (≈70 ± 20 km s-1) imply the bow shock interpretation for the nebula. Thus, IRC -10414 represents the third case of a bow-shock-producing RSG and the first one with a bow shock visible at optical wavelengths. We discuss the smooth appearance of the bow shocks around IRC -10414 and Betelgeuse and propose that one of the necessary conditions for stability of bow shocks generated by RSGs is the ionization of the stellar wind. Possible ionization sources of the wind of IRC -10414 are proposed and discussed.

  15. Conversion of piston-driven shocks from powerful solar flares to blast wave shocks in the solar wind

    International Nuclear Information System (INIS)

    Pinter, S.

    1990-01-01

    It was suggested by Smart and Shea (1985) that the time of arrival of solar-flare-generated shock waves at any point in space may be predicted by assuming that they are first driven from the Sun after which they decay into blast shocks. Their study was extended by using the duration of the Type IV radio emission as a phenomenological symptom of the piston-driven phase of these shocks. Using a sample of 39 cases of combined Type II/Type IV observations from 1972 to 1982 solar flares, it was found that the average predicted times-of-arrival of these shocks to Earth (and elsewhere) deviate from the actual times by 1.40 hr with a standard deviation of 1.25 hr. On the average, a representative shock from this sample is emitted from a powerful flare with a velocity of 1,560 km sec -1 ; moves at a constant inertial velocity to a distance of 0.12 AU after which it begins to decelerate as a classical (Sedov-type) blast shock that is convected by the ambient solar wind as suggested by Smart and Shea; and arrives to Earth 45.8 hr after its initiation in the Sun. Shocks that appear to deviate from this phenomenological scenario by virtue of lack of detection on Earth are assumed to decay into fast mode MHD waves. (author). 7 figs., 1 tab., 53 refs

  16. X-Ray Emission Properties of Supernova Remnants

    NARCIS (Netherlands)

    Vink, J.; Alsabti, A.W.; Murdin, P.

    2016-01-01

    X-ray emission from supernova remnants can be broadly divided into thermal X-ray emission from the shock-heated plasmas and in nonthermal (synchrotron) emission caused by very high-energy (10–100 TeV) electrons moving in the magnetic fields of the hot plasmas. The thermal X-ray emission of young

  17. Shock Dynamics in Stellar Outbursts. I. Shock Formation

    Energy Technology Data Exchange (ETDEWEB)

    Ro, Stephen; Matzner, Christopher D., E-mail: ro@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada)

    2017-05-20

    Wave-driven outflows and non-disruptive explosions have been implicated in pre-supernova outbursts, supernova impostors, luminous blue variable eruptions, and some narrow-line and superluminous supernovae. To model these events, we investigate the dynamics of stars set in motion by strong acoustic pulses and wave trains, focusing on nonlinear wave propagation, shock formation, and an early phase of the development of a weak shock. We identify the shock formation radius, showing that a heuristic estimate based on crossing characteristics matches an exact expansion around the wave front and verifying both with numerical experiments. Our general analytical condition for shock formation applies to one-dimensional motions within any static environment, including both eruptions and implosions. We also consider the early phase of shock energy dissipation. We find that waves of super-Eddington acoustic luminosity always create shocks, rather than damping by radiative diffusion. Therefore, shock formation is integral to super-Eddington outbursts.

  18. International Experience in Developing Low-Emission Combustors for Land-Based, Large Gas-Turbine Units: Mitsubishi Heavy Industries' Equipment

    Science.gov (United States)

    Bulysova, L. A.; Vasil'ev, V. D.; Berne, A. L.; Gutnik, M. N.; Ageev, A. V.

    2018-05-01

    This is the second paper in a series of publications summarizing the international experience in the development of low-emission combustors (LEC) for land-based, large (above 250 MW) gas-turbine units (GTU). The purpose of this series is to generalize and analyze the approaches used by various manufacturers in designing flowpaths for fuel and air in LECs, managing fuel combustion, and controlling the fuel flow. The efficiency of advanced GTUs can be as high as 43% (with an output of 350-500 MW) while the efficiency of 600-800 MW combined-cycle units with these GTUs can attain 63.5%. These high efficiencies require a compression ratio of 20-24 and a temperature as high as 1600°C at the combustor outlet. Accordingly, the temperature in the combustion zone also rises. All the requirements for the control of harmful emissions from these GTUs are met. All the manufacturers and designers of LECs for modern GTUs encounter similar problems, such as emissions control, combustion instability, and reliable cooling of hot path parts. Methods of their elimination are different and interesting from the standpoint of science and practice. One more essential requirement is that the efficiency and environmental performance indices must be maintained irrespective of the fuel composition or heating value and also in operation at part loads below 40% of rated. This paper deals with Mitsubishi Series M701 GTUs, F, G, or J class, which have gained a good reputation in the power equipment market. A design of a burner for LECs and a control method providing stable low-emission fuel combustion are presented. The advantages and disadvantages of the use of air bypass valves installed in each liner to maintain a nearly constant air to fuel ratio within a wide range of GTU loads are described. Methods for controlling low- and high-frequency combustion instabilities are outlined. Upgrading of the cooling system for the wall of a liner and a transition piece is of great interest. Change over

  19. VARIABILITY OF THE SiO THERMAL LINE EMISSION TOWARD THE YOUNG L1448-mm OUTFLOW

    International Nuclear Information System (INIS)

    Jimenez-Serra, I.; MartIn-Pintado, J.; RodrIguez-Franco, A.; Winters, J.-M.; Caselli, P.

    2011-01-01

    The detection of narrow SiO thermal emission toward young outflows has been proposed to be a signature of the magnetic precursor of C-shocks. Recent modeling of the SiO emission across C-shocks predicts variations in the SiO line intensity and line shape at the precursor and intermediate-velocity regimes in only a few years. We present high angular resolution (3.''8 x 3.''3) images of the thermal SiO J = 2→1 emission toward the L1448-mm outflow in two epochs (2004 November-2005 February, 2009 March-April). Several SiO condensations have appeared at intermediate velocities (20-50 km s -1 ) toward the redshifted lobe of the outflow since 2005. Toward one of the condensations (clump D), systematic differences of the dirty beams between 2005 and 2009 could be responsible for the SiO variability. At higher velocities (50-80 km s -1 ), SiO could also have experienced changes in its intensity. We propose that the SiO variability toward L1448-mm is due to a real SiO enhancement by young C-shocks at the internal working surface between the jet and the ambient gas. For the precursor regime (5.2-9.2 km s -1 ), several narrow and faint SiO components are detected. The narrow SiO components tend to be compact, transient and show elongated (bow-shock) morphologies perpendicular to the jet. We speculate that these features are associated with the precursor of C-shocks appearing at the interface of the new SiO components seen at intermediate velocities.

  20. Grain destruction in interstellar shocks

    International Nuclear Information System (INIS)

    Seab, C.G.; Shull, J.M.

    1984-01-01

    One of the principal methods for removing grains from the Interstellar Medium is to destroy them in shock waves. Previous theoretical studies of shock destruction have generally assumed only a single size and type of grain; most do not account for the effect of the grain destruction on the structure of the shock. Earlier calculations have been improved in three ways: first, by using a ''complete'' grain model including a distribution of sizes and types of grains; second, by using a self-consistent shock structure that incorporates the changing elemental depletions as the grains are destroyed; and third, by calculating the shock-processed ultraviolet extinction curves for comparison with observations. (author)

  1. The structure of steady shock waves in porous metals

    Science.gov (United States)

    Czarnota, Christophe; Molinari, Alain; Mercier, Sébastien

    2017-10-01

    The paper aims at developing an understanding of steady shock wave propagation in a ductile metallic material containing voids. Porosity is assumed to be less than 0.3 and voids are not connected (foams are not considered). As the shock wave is traveling in the porous medium, the voids are facing a rapid collapse. During this dynamic compaction process, material particles are subjected to very high acceleration in the vicinity of voids, thus generating acceleration forces at the microscale that influence the overall response of the porous material. Analyzing how stationary shocks are influenced by these micro-inertia effects is the main goal of this work. The focus is essentially on the shock structure, ignoring oscillatory motion of pores prevailing at the tail of the shock wave. Following the constitutive framework developed by Molinari and Ravichandran (2004) for the analysis of steady shock waves in dense metals, an analytical approach of steady state propagation of plastic shocks in porous metals is proposed. The initial void size appears as a characteristic internal length that scales the overall dynamic response, thereby contributing to the structuring of the shock front. This key feature is not captured by standard damage models where the porosity stands for the single damage parameter with no contribution of the void size. The results obtained in this work provide a new insight in the fundamental understanding of shock waves in porous media. In particular, a new scaling law relating the shock width to the initial void radius is obtained when micro-inertia effects are significant.

  2. The collision of a strong shock with a gas cloud: a model for Cassiopeia A

    International Nuclear Information System (INIS)

    Sgro, A.G.

    1975-01-01

    The result of the collision of the shock with the cloud is a shock traveling around the cloud, a shock transmitted into the cloud, and a shock reflected from the cloud. By equating the cooling time of the posttransmitted shock gas to the time required for the transmitted shock to travel the length of the cloud, a critical cloud density n/subc/ /sup prime/ is defined. For clouds with density greater than n/subc/ /sup prime/, the posttransmitted shock gas cools rapidly and then emits the lines of the lower ionization stages of its constituent elements. The structure of such and its expected appearance to an observer are discussed and compared with the quasi-stationary condensations of Cas A. Conversely, clouds with density less than n/subc//sup prime/ remain hot for several thousand years, and are sources of X-radiation whose temperatures are much less than that of the intercloud gas. After the transmitted shock passes, the cloud pressure is greater than the pressure in the surrounding gas, causing the cloud to expand and the emission to decrease from its value just after the collision. A model in which the soft X-radiation of Cas A is due to a collection of such clouds is discussed. The faint emission patches to the north of Cas A are interpreted as preshocked clouds which will probably become quasi-stationary condensations after being hit by the shock

  3. Adjustable Shock Absorbers

    OpenAIRE

    Adamiec, Radek

    2012-01-01

    Bakalářská práce obsahuje přehled používaných tlumičů osobních automobilů, závodních automobilů a motocyklů. Jsou zde popsány systémy t lumením, konstrukce tlumičů a vidlic používaných u motocyklů. Dále je zde přehled prvků používaných u podvozků automobilů. This bachelor´s thesis contains the survey of the shock absorbers of passenger cars, racing cars and motorcycles. Are described damping systems, the design used shock absorbers and forks for motorcycles. Then there is the list of the e...

  4. Radiative relativistic shock adiabate

    International Nuclear Information System (INIS)

    Tsintsadze, L.N.; Nishikawa, K.

    1997-01-01

    The influences of thermal radiation on the state equation of shock waves, derived in the previous paper [L. N. Tsintsadze, Phys. Plasmas 2, 4462 (1995)], are studied and a series of relations of thermodynamic quantities that hold for shock waves are derived. It is shown that the presence of radiation can strongly change the compressibility of the plasma. It is well known that for polytropic gases the compressibility cannot change more than four times the initial value in the case of nonrelativistic temperatures. The numerical calculations show that there are no such restrictions, when the radiation energy exceeds the kinetic energy of the plasma. The ultrarelativistic temperature range is also covered in our numerical calculations. Also studied are the influences of the radiation on the PT and the TV diagrams. A significant modification due to radiation is found in every case studied. copyright 1997 American Institute of Physics

  5. POSTURAL SHOCK IN PREGNANCY

    Science.gov (United States)

    Wilkening, Ralph L.; Knauer, John; Larson, Roger K.

    1955-01-01

    Signs and symptoms of shock may be produced in some patients in late pregnancy by putting them in the dorsal recumbent posture. Change from this position will relieve the condition. The features of the supine hypotensive syndrome can be duplicated by applying pressure to the abdomen with the patient in a lateral position. The postural variations of venous pressure, blood pressure, and pulse appear to be due to obstruction of venous return from the lower portion of the body caused by the large uterus of late pregnancy compressing the vena cava. When shock is observed in a woman in late pregnancy, she should be turned to a lateral position before more active measures of treatment are begun. ImagesFigure 1. PMID:14351983

  6. Shock Isolation Elements Testing for High Input Loadings. Volume III. Mechanical Shock Isolation Elements.

    Science.gov (United States)

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*SPRINGS, (*SHOCK(MECHANICS), REDUCTION), TORSION BARS, ELASTOMERS, DAMPING, EQUATIONS OF MOTION, MODEL TESTS, TEST METHODS, NUCLEAR EXPLOSIONS, HARDENING.

  7. Shock resistance testing

    International Nuclear Information System (INIS)

    Pouard, M.

    1984-03-01

    In the framework of mechanical tests and to answer the different requests for tests, the T.C.R (Transport Conditionnement et Retraitement) laboratory got test facilities. These installations allow to carry out tests of resistance to shocks, mainly at the safety level of components of nuclear power plants, mockups of transport casks for fuel elements and transport containers for radioactive materials. They include a tower and a catapult. This paper give a decription of the facilities and explain their operation way [fr

  8. On Modeling Risk Shocks

    OpenAIRE

    Dorofeenko, Victor; Lee, Gabriel; Salyer, Kevin; Strobel, Johannes

    2016-01-01

    Within the context of a financial accelerator model, we model time-varying uncertainty (i.e. risk shocks) through the use of a mixture Normal model with time variation in the weights applied to the underlying distributions characterizing entrepreneur productivity. Specifically, we model capital producers (i.e. the entrepreneurs) as either low-risk (relatively small second moment for productivity) and high-risk (relatively large second moment for productivity) and the fraction of both types is...

  9. The Shock Doctrine

    OpenAIRE

    Dionysios K. Solomos; Dimitrios N. Koumparoulis

    2011-01-01

    Naomi Klein attempts to redefine the economic history discovering the historical continuities and to reveal the neoliberal theory which functions via the utilization of specific “tools”. The state of shock is the key for the opponents of Chicago School and Milton Friedman in order for them to establish neoliberal policies and to promote the deregulated capitalism which includes less welfare state, less public sector, less regulation, weakened labor unions, privatizations and laissez-faire. Th...

  10. Characterization of shocked beryllium

    Directory of Open Access Journals (Sweden)

    Papin P.A.

    2012-08-01

    Full Text Available While numerous studies have investigated the low-strain-rate constitutive response of beryllium, the combined influence of high strain rate and temperature on the mechanical behavior and microstructure of beryllium has received limited attention over the last 40 years. In the current work, high strain rate tests were conducted using both explosive drive and a gas gun to accelerate the material. Prior studies have focused on tensile loading behavior, or limited conditions of dynamic strain rate and/or temperature. Two constitutive strength (plasticity models, the Preston-Tonks-Wallace (PTW and Mechanical Threshold Stress (MTS models, were calibrated using common quasi-static and Hopkinson bar data. However, simulations with the two models give noticeably different results when compared with the measured experimental wave profiles. The experimental results indicate that, even if fractured by the initial shock loading, the Be remains sufficiently intact to support a shear stress following partial release and subsequent shock re-loading. Additional “arrested” drive shots were designed and tested to minimize the reflected tensile pulse in the sample. These tests were done to both validate the model and to put large shock induced compressive loads into the beryllium sample.

  11. Experimental and numerical investigation of reactive shock-accelerated flows

    Energy Technology Data Exchange (ETDEWEB)

    Bonazza, Riccardo [Univ. of Wisconsin, Madison, WI (United States). Dept. of Engineering Physics

    2016-12-20

    The main goal of this program was to establish a qualitative and quantitative connection, based on the appropriate dimensionless parameters and scaling laws, between shock-induced distortion of astrophysical plasma density clumps and their earthbound analog in a shock tube. These objectives were pursued by carrying out laboratory experiments and numerical simulations to study the evolution of two gas bubbles accelerated by planar shock waves and compare the results to available astrophysical observations. The experiments were carried out in an vertical, downward-firing shock tube, 9.2 m long, with square internal cross section (25×25 cm2). Specific goals were to quantify the effect of the shock strength (Mach number, M) and the density contrast between the bubble gas and its surroundings (usually quantified by the Atwood number, i.e. the dimensionless density difference between the two gases) upon some of the most important flow features (e.g. macroscopic properties; turbulence and mixing rates). The computational component of the work performed through this program was aimed at (a) studying the physics of multi-phase compressible flows in the context of astrophysics plasmas and (b) providing a computational connection between laboratory experiments and the astrophysical application of shock-bubble interactions. Throughout the study, we used the FLASH4.2 code to run hydrodynamical and magnetohydrodynamical simulations of shock bubble interactions on an adaptive mesh.

  12. Experimental and numerical investigation of reactive shock-accelerated flows

    International Nuclear Information System (INIS)

    Bonazza, Riccardo

    2016-01-01

    The main goal of this program was to establish a qualitative and quantitative connection, based on the appropriate dimensionless parameters and scaling laws, between shock-induced distortion of astrophysical plasma density clumps and their earthbound analog in a shock tube. These objectives were pursued by carrying out laboratory experiments and numerical simulations to study the evolution of two gas bubbles accelerated by planar shock waves and compare the results to available astrophysical observations. The experiments were carried out in an vertical, downward-firing shock tube, 9.2 m long, with square internal cross section (25x25 cm"2). Specific goals were to quantify the effect of the shock strength (Mach number, M) and the density contrast between the bubble gas and its surroundings (usually quantified by the Atwood number, i.e. the dimensionless density difference between the two gases) upon some of the most important flow features (e.g. macroscopic properties; turbulence and mixing rates). The computational component of the work performed through this program was aimed at (a) studying the physics of multi-phase compressible flows in the context of astrophysics plasmas and (b) providing a computational connection between laboratory experiments and the astrophysical application of shock-bubble interactions. Throughout the study, we used the FLASH4.2 code to run hydrodynamical and magnetohydrodynamical simulations of shock bubble interactions on an adaptive mesh.

  13. Selfsimilar time dependent shock structures

    International Nuclear Information System (INIS)

    Beck, R.; Drury, L.O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The same argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions

  14. Selfsimilar time dependent shock structures

    Science.gov (United States)

    Beck, R.; Drury, L. O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The ame argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions.

  15. AN EXTERNAL SHOCK ORIGIN OF GRB 141028A

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, J. Michael; Bégué, Damien; Ryde, Felix [The Oskar Klein Centre for Cosmoparticle Physics, AlbaNova, SE-106 91 Stockholm (Sweden); Omodei, Nicola [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Pe’er, Asaf [Physics Department, University College Cork, Cork (Ireland); Racusin, J. L.; Cucchiara, A., E-mail: jamesb@kth.se, E-mail: damienb@kth.se [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2016-05-10

    The prompt emission of the long, smooth, and single-pulsed gamma-ray burst, GRB 141028A, is analyzed under the guise of an external shock model. First, we fit the γ -ray spectrum with a two-component photon model, namely, synchrotron+blackbody, and then fit the recovered evolution of the synchrotron νF{sub ν} peak to an analytic model derived considering the emission of a relativistic blast wave expanding into an external medium. The prediction of the model for the νF{sub ν} peak evolution matches well with the observations. We observe the blast wave transitioning into the deceleration phase. Furthermore, we assume the expansion of the blast wave to be nearly adiabatic, motivated by the low magnetic field deduced from the observations. This allows us to recover within an order of magnitude the flux density at the νF{sub ν} peak, which is remarkable considering the simplicity of the analytic model. Under this scenario we argue that the distinction between prompt and afterglow emission is superfluous as both early-time emission and late-time emission emanate from the same source. While the external shock model is clearly not a universal solution, this analysis opens the possibility that at least some fraction of GRBs can be explained with an external shock origin of their prompt phase.

  16. Shock Heating of the Merging Galaxy Cluster A521

    Science.gov (United States)

    Bourdin, H.; Mazzotta, P.; Markevitch, M.; Giacintucci, S.; Brunetti, G.

    2013-01-01

    A521 is an interacting galaxy cluster located at z = 0.247, hosting a low-frequency radio halo connected to an eastern radio relic. Previous Chandra observations hinted at the presence of an X-ray brightness edge at the position of the relic, which may be a shock front. We analyze a deep observation of A521 recently performed with XMM-Newton in order to probe the cluster structure up to the outermost regions covered by the radio emission. The cluster atmosphere exhibits various brightness and temperature anisotropies. In particular, two cluster cores appear to be separated by two cold fronts. We find two shock fronts, one that was suggested by Chandra and that is propagating to the east, and another to the southwestern cluster outskirt. The two main interacting clusters appear to be separated by a shock-heated region, which exhibits a spatial correlation with the radio halo. The outer edge of the radio relic coincides spatially with a shock front, suggesting that this shock is responsible for the generation of cosmic-ray electrons in the relic. The propagation direction and Mach number of the shock front derived from the gas density jump, M = 2.4 +/- 0.2, are consistent with expectations from the radio spectral index, under the assumption of Fermi I acceleration mechanism.

  17. Generation of Two Successive Shock Waves Focusedto a Common Focal Point

    Czech Academy of Sciences Publication Activity Database

    Šunka, Pavel; Stelmashuk, Vitaliy; Babický, Václav; Člupek, Martin; Beneš, J.; Poučková, P.; Kašpar, J.; Bodnár, M.

    2006-01-01

    Roč. 34, č. 4 (2006), s. 1382-1385 ISSN 0093-3813. [International Power Modulator Conference. Washington D.C., 14.5.2006-18.5.2006] R&D Projects: GA ČR(CZ) GA202/05/0685 Institutional research plan: CEZ:AV0Z20430508 Keywords : Cavitation collpse * double shocks * focused shock waves * liver injury * secondary shocks Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.144, year: 2006

  18. Shock initiation of explosives: Temperature spikes and growth spurts

    Science.gov (United States)

    Bassett, Will P.; Dlott, Dana D.

    2016-08-01

    When energetic materials are subjected to high-velocity impacts, the first steps in the shock-to-detonation transition are the creation, ignition, and growth of hot spots. We used 1-3.2 km s-1 laser-launched flyer plates to impact powdered octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, a powerful explosive, and monitored hundreds of emission bursts with an apparatus that determined temperature and emissivity at all times. The time-dependent volume fraction of hot spots was determined by measuring the time-dependent emissivity. After the shock, most hot spots extinguished, but the survivors smoldered for hundreds of nanoseconds until their temperatures spiked, causing a hot spot growth spurt. Depending on the impact duration, the growth spurts could be as fast as 300 ns and as slow as 13 μs.

  19. A Shocking Surprise in Stephan's Quintet

    Science.gov (United States)

    2006-01-01

    This false-color composite image of the Stephan's Quintet galaxy cluster clearly shows one of the largest shock waves ever seen (green arc). The wave was produced by one galaxy falling toward another at speeds of more than one million miles per hour. The image is made up of data from NASA's Spitzer Space Telescope and a ground-based telescope in Spain. Four of the five galaxies in this picture are involved in a violent collision, which has already stripped most of the hydrogen gas from the interiors of the galaxies. The centers of the galaxies appear as bright yellow-pink knots inside a blue haze of stars, and the galaxy producing all the turmoil, NGC7318b, is the left of two small bright regions in the middle right of the image. One galaxy, the large spiral at the bottom left of the image, is a foreground object and is not associated with the cluster. The titanic shock wave, larger than our own Milky Way galaxy, was detected by the ground-based telescope using visible-light wavelengths. It consists of hot hydrogen gas. As NGC7318b collides with gas spread throughout the cluster, atoms of hydrogen are heated in the shock wave, producing the green glow. Spitzer pointed its infrared spectrograph at the peak of this shock wave (middle of green glow) to learn more about its inner workings. This instrument breaks light apart into its basic components. Data from the instrument are referred to as spectra and are displayed as curving lines that indicate the amount of light coming at each specific wavelength. The Spitzer spectrum showed a strong infrared signature for incredibly turbulent gas made up of hydrogen molecules. This gas is caused when atoms of hydrogen rapidly pair-up to form molecules in the wake of the shock wave. Molecular hydrogen, unlike atomic hydrogen, gives off most of its energy through vibrations that emit in the infrared. This highly disturbed gas is the most turbulent molecular hydrogen ever seen. Astronomers were surprised not only by the turbulence

  20. DISRUPTING SHOCKS IN POSTWAR GLOBAL ECONOMIC EXPANSION

    Directory of Open Access Journals (Sweden)

    Dumitru FILIPEANU

    2016-06-01

    Full Text Available The coherence of the global economic system, created by its upswing in the first postwar decades, started to crumble in the ’70s. The destabilizing shocks affected the entire world, but in an uneven manner, in different geographical areas and at different times, being felt most acutely, with devastating economic and social effects, in Third World countries. Although the developed countries were affected as well, they always had means to combat or to diminish the adverse effects of the crises, leading to "gentler" consequences. This paper focuses on four main aspects in postwar global economic expansion, namely: the ’70s – the international monetary crisis and the oil shocks; the foreign debt crisis; the Latin American debt crisis, the Asian financial crises and the current global crisis.

  1. 3D numerical modeling of YSO accretion shocks

    Directory of Open Access Journals (Sweden)

    Matsakos T.

    2014-01-01

    Full Text Available The dynamics of YSO accretion shocks is determined by radiative processes as well as the strength and structure of the magnetic field. A quasi-periodic emission signature is theoretically expected to be observed, but observations do not confirm any such pattern. In this work, we assume a uniform background field, in the regime of optically thin energy losses, and we study the multi-dimensional shock evolution in the presence of perturbations, i.e. clumps in the stream and an acoustic energy flux flowing at the base of the chromosphere. We perform 3D MHD simulations using the PLUTO code, modelling locally the impact of the infalling gas onto the chromosphere. We find that the structure and dynamics of the post-shock region is strongly dependent on the plasma-beta (thermal over magnetic pressure, different values of which may give distinguishable emission signatures, relevant for observations. In particular, a strong magnetic field effectively confines the plasma inside its flux tubes and leads to the formation of quasi-independent fibrils. The fibrils may oscillate out of phase and hence the sum of their contributions in the emission results in a smooth overall profile. On the contrary, a weak magnetic field is not found to have any significant effect on the shocked plasma and the turbulent hot slab that forms is found to retain its periodic signature.

  2. The size effects upon shock plastic compression of nanocrystals

    Science.gov (United States)

    Malygin, G. A.; Klyavin, O. V.

    2017-10-01

    For the first time a theoretical analysis of scale effects upon the shock plastic compression of nanocrystals is implemented in the context of a dislocation kinetic approach based on the equations and relationships of dislocation kinetics. The yield point of crystals τy is established as a quantitative function of their cross-section size D and the rate of shock deformation as τy ɛ2/3 D. This dependence is valid in the case of elastic stress relaxation on account of emission of dislocations from single-pole Frank-Read sources near the crystal surface.

  3. Risk shocks and housing markets

    OpenAIRE

    Dorofeenko, Viktor; Lee, Gabriel S.; Salyer, Kevin D.

    2010-01-01

    Abstract: This paper analyzes the role of uncertainty in a multi-sector housing model with financial frictions. We include time varying uncertainty (i.e. risk shocks) in the technology shocks that affect housing production. The analysis demonstratesthat risk shocks to the housing production sector are a quantitatively important impulse mechanism for the business cycle. Also, we demonstrate that bankruptcy costs act as an endogenous markup factor in housing prices; as a consequence, the volati...

  4. Joint project of the international network of agencies for health technology assessment--Part 1: Survey results on diffusion, assessment, and clinical use of positron emission tomography.

    Science.gov (United States)

    Hastings, John; Adams, Elizabeth J

    2006-01-01

    The International Network of Agencies for Health Technology Assessment (INAHTA) has been tracking activities associated with the clinical use of positron emission tomography (PET) in its members' healthcare systems since 1997 and published its first Joint Project report on PET in 1999. Part 1 of this Joint Project report presents survey results on diffusion, assessment activities, and policy for clinical use related to PET among INAHTA members since 1999. INAHTA members were surveyed in 2003-2004. Twenty-seven INAHTA agencies (69 percent response rate) from nineteen countries responded to the survey. Dedicated PET systems are the most universally installed systems to date. Mobile scanners and modified gamma cameras are used occasionally as lower cost alternatives, and interest in PET-computed tomography hybrid models is rising despite limited assessment of impact on service planning. PET was used and assessed most commonly for managing patients with cancer. All respondents reported having some form of public funding for clinical PET frequently linked to data collection for the purpose of gathering evidence to refine clinical use and guide resource allocation toward indications that maximize clinical and cost-effectiveness. The use of HTA within a continuous quality improvement framework can help optimize scarce resources for evaluation and use of high cost diagnostic technologies such as PET, particularly where potential clinical or cost-effectiveness is considerable but conclusive evidence is lacking.

  5. Detection of hemodynamic impairment using magnetic resonance angiography in patients with internal carotid artery stenoocclusive disease. Comparison with quantitative brain perfusion single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Hirooka, Ryonoshin; Ogasawara, Kuniaki

    2008-01-01

    Cerebrovascular reactivity (CVR) to acetazolamideis a key parameter in determining the severity of hemodynamic impairment in patients with major cerebral artery occlusive disease. The aim of the present study is to validate the accuracy of magnetic resonance angiography (MRA) for detecting hemodynamic impairment by correlating detectability of the middle cerebral artery obtained by MRA with CVR measured by single-photon emission computed tomography (SPECT) in patients with internal carotid artery (ICA) occlusive disease. Ninety-four patients with chronic ICA occlusion underwent single slab three-dimensional time-of-flight MRA and SPECT. SPECT-CVR was calculated by measured cerebral blood flow before and after acetazolamide challenge. CVR was significantly lower in patients without detection of any portion (M1, M2 or M3) of the MCA than in those with detection of all portions. When SPECT-CVR lower than the mean- 2 standard deviation (SD) obtained in normal subjects was defined as reduced and the SPECT-CVR was assumed as the true determinant of hemodynamic impairment, MRA provided 92% sensitivity and 73% specificity, with 96% negative predictive value for detecting patients with reduced CVR. The present MRA method is effective for the identification of patients with hemodynamic impairment. (author)

  6. A plume-in-grid approach to characterize air quality impacts of aircraft emissions at the Hartsfield–Jackson Atlanta International Airport

    Directory of Open Access Journals (Sweden)

    J. Rissman

    2013-09-01

    Full Text Available This study examined the impacts of aircraft emissions during the landing and takeoff cycle on PM2.5 concentrations during the months of June and July 2002 at the Hartsfield–Jackson Atlanta International Airport. Primary and secondary pollutants were modeled using the Advanced Modeling System for Transport, Emissions, Reactions, and Deposition of Atmospheric Matter (AMSTERDAM. AMSTERDAM is a modified version of the Community Multiscale Air Quality (CMAQ model that incorporates a plume-in-grid process to simulate emissions sources of interest at a finer scale than can be achieved using CMAQ's model grid. Three fundamental issues were investigated: the effects of aircraft on PM2.5 concentrations throughout northern Georgia, the differences resulting from use of AMSTERDAM's plume-in-grid process rather than a traditional CMAQ simulation, and the concentrations observed in aircraft plumes at subgrid scales. Comparison of model results with an air quality monitor located in the vicinity of the airport found that normalized mean bias ranges from −77.5% to 6.2% and normalized mean error ranges from 40.4% to 77.5%, varying by species. Aircraft influence average PM2.5 concentrations by up to 0.232 μg m−3 near the airport and by 0.001–0.007 μg m−3 throughout the Atlanta metro area. The plume-in-grid process increases concentrations of secondary PM pollutants by 0.005–0.020 μg m−3 (compared to the traditional grid-based treatment but reduces the concentration of non-reactive primary PM pollutants by up to 0.010 μg m−3, with changes concentrated near the airport. Examination of subgrid-scale results indicates that median aircraft contribution to grid cells is higher than median puff concentration in the airport's grid cell and outside of a 20 km × 20 km square area centered on the airport, while in a 12 km × 12 km square ring centered on the airport, puffs have median concentrations over an order of magnitude higher than aircraft

  7. Health shocks and risk aversion.

    Science.gov (United States)

    Decker, Simon; Schmitz, Hendrik

    2016-12-01

    We empirically assess whether a health shock influences individual risk aversion. We use grip strength data to obtain an objective health shock indicator. In order to account for the non-random nature of our data regression-adjusted matching is employed. Risk preferences are traditionally assumed to be constant. However, we find that a health shock increases individual risk aversion. The finding is robust to a series of sensitivity analyses and persists for at least four years after the shock. Income changes do not seem to be the driving mechanism. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Shock in the emergency department

    DEFF Research Database (Denmark)

    Holler, Jon Gitz; Henriksen, Daniel Pilsgaard; Mikkelsen, Søren

    2016-01-01

    BACKGROUND: The knowledge of the frequency and associated mortality of shock in the emergency department (ED) is limited. The aim of this study was to describe the incidence, all-cause mortality and factors associated with death among patients suffering shock in the ED. METHODS: Population...... failures. Outcomes were annual incidence per 100,000 person-years at risk (pyar), all-cause mortality at 0-7, and 8-90 days and risk factors associated with death. RESULTS: We identified 1646 of 438,191 (0.4 %) ED patients with shock at arrival. Incidence of shock increased from 53.8 to 80.6 cases per 100...

  9. Shock compression of diamond crystal

    OpenAIRE

    Kondo, Ken-ichi; Ahrens, Thomas J.

    1983-01-01

    Two shock wave experiments employing inclined mirrors have been carried out to determine the Hugoniot elastic limit (HEL), final shock state at 191 and 217 GPa, and the post-shock state of diamond crystal, which is shock-compressed along the intermediate direction between the and crystallographic axes. The HEL wave has a velocity of 19.9 ± 0.3 mm/µsec and an amplitude of 63 ± 28 GPa. An alternate interpretation of the inclined wedge mirror streak record suggests a ramp precursor wave and th...

  10. A Shocking Solar Nebula?

    OpenAIRE

    Liffman, Kurt

    2009-01-01

    It has been suggested that shock waves in the solar nebula formed the high temperature materials observed in meteorites and comets. It is shown that the temperatures at the inner rim of the solar nebula could have been high enough over a sufficient length of time to produce chondrules, CAIs, refractory dust grains and other high-temperature materials observed in comets and meteorites. The solar bipolar jet flow may have produced an enrichment of 16O in the solar nebula over time and the chond...

  11. Myths of "shock therapy".

    Science.gov (United States)

    Fink, M

    1977-09-01

    The author discusses the myths of the ECT process--that shock and the convulsion are essential, memory loss and brain damage are inescapable, and little is known of the process--and assesses the fallacies in these ideas. Present views of the ECT process suggest that its mode of action in depression may best be described as a prolonged form of diencephalic stimulation, particularly useful to affect the hypothalamic dysfunctions that characterize depressive illness. The author emphasizes the need for further study of this treatment modality and for self-regulation by the profession.

  12. DETECTION OF HIGH-ENERGY GAMMA-RAY EMISSION DURING THE X-RAY FLARING ACTIVITY IN GRB 100728A

    International Nuclear Information System (INIS)

    Abdo, A. A.; Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Borgland, A. W.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Ballet, J.; Barbiellini, G.; Baring, M. G.; Bastieri, D.; Bhat, P. N.; Bissaldi, E.; Bonamente, E.; Bonnell, J.; Bouvier, A.; Brigida, M.

    2011-01-01

    We present the simultaneous Swift and Fermi observations of the bright GRB 100728A and its afterglow. The early X-ray emission is dominated by a vigorous flaring activity continuing until 1 ks after the burst. In the same time interval, high-energy emission is significantly detected by the Fermi/Large Area Telescope. Marginal evidence of GeV emission is observed up to later times. We discuss the broadband properties of this burst within both the internal and external shock scenarios, with a particular emphasis on the relation between X-ray flares, the GeV emission, and a continued long-duration central engine activity as their power source.

  13. Gravitational shock waves and extreme magnetomaterial shock waves

    International Nuclear Information System (INIS)

    Lichnerowicz, Andre.

    1975-01-01

    Within an astrophysical context corresponding to high densities, a self-gravitating model is studied, which is the set of an extreme material medium of infinite conductivity and of a magnetic field. Corresponding shock waves generate necessarily, in general, gravitational shock waves [fr

  14. Shock Producers and Shock Absorbers in the Crisis

    OpenAIRE

    Sinn, Hans-Werner

    2009-01-01

    It is not surprising that the U.S. has been by far the world’s largest shock producer in this crisis. The big shock absorbers on the other hand were Japan, Russia and Germany, whose exports shrank more than their imports.

  15. Simulations of Converging Shock Collisions for Shock Ignition

    Science.gov (United States)

    Sauppe, Joshua; Dodd, Evan; Loomis, Eric

    2016-10-01

    Shock ignition (SI) has been proposed as an alternative to achieving high gain in inertial confinement fusion (ICF) targets. A central hot spot below the ignition threshold is created by an initial compression pulse, and a second laser pulse drives a strong converging shock into the fuel. The collision between the rebounding shock from the compression pulse and the converging shock results in amplification of the converging shock and increases the hot spot pressure above the ignition threshold. We investigate shock collision in SI drive schemes for cylindrical targets with a polystyrene foam interior using radiation-hydrodynamics simulations with the RAGE code. The configuration is similar to previous targets fielded on the Omega laser. The CH interior results in a lower convergence ratio and the cylindrical geometry facilitates visualization of the shock transit using an axial X-ray backlighter, both of which are important for comparison to potential experimental measurements. One-dimensional simulations are used to determine shock timing, and the effects of low mode asymmetries in 2D computations are also quantified. LA-UR-16-24773.

  16. Coping with anxiety and rebuilding identity: A psychosynthesis approach to culture shock

    NARCIS (Netherlands)

    Lombard, Catherine Ann

    2014-01-01

    As the number of international students continues to increase worldwide, their experience of culture shock has been well-researched. Missing, however, from the culture shock literature is the perspective of psychosynthesis psychology and its methodology to deal with the affective, behavioral, and

  17. Confinement effects of shock waves on laser-induced plasma from a graphite target

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Feiling; Liang, Peipei; Yang, Xu; Cai, Hua; Wu, Jiada; Xu, Ning; Ying, Zhifeng; Sun, Jian, E-mail: jsun@fudan.edu.cn [Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Department of Optical Science and Engineering, Fudan University, Shanghai 200433 (China)

    2015-06-15

    The spatial confinement effects of shock waves on the laser-induced plasma (LIP) from a graphite target in air were studied by probe beam deflection (PBD) measurements and optical emission spectroscopy (OES). A clear relationship between the confinement of the LIP by the sho