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Sample records for shock-loaded tin xrd

  1. Numerical Simulation of Wave Propagation and Phase Transition of Tin under Shock-Wave Loading

    International Nuclear Information System (INIS)

    Hai-Feng, Song; Hai-Feng, Liu; Guang-Cai, Zhang; Yan-Hong, Zhao

    2009-01-01

    We undertake a numerical simulation of shock experiments on tin reported in the literature, by using a multiphase equation of state (MEOS) and a multiphase Steinberg Guinan (MSG) constitutive model for tin in the β, γ and liquid phases. In the MSG model, the Bauschinger effect is considered to better describe the unloading behavior. The phase diagram and Hugoniot of tin are calculated by MEOS, and they agree well with the experimental data. Combined with the MEOS and MSG models, hydrodynamic computer simulations are successful in reproducing the measured velocity profile of the shock wave experiment. Moreover, by analyzing the mass fraction contour as well as stress and temperature profiles of each phase for tin, we further discuss the complex behavior of tin under shock-wave loading. (condensed matter: structure, mechanical and thermal properties)

  2. Molecular dynamics simulations of ejecta production from sinusoidal tin surfaces under supported and unsupported shocks

    Science.gov (United States)

    Wu, Bao; Wu, FengChao; Zhu, YinBo; Wang, Pei; He, AnMin; Wu, HengAn

    2018-04-01

    Micro-ejecta, an instability growth process, occurs at metal/vacuum or metal/gas interface when compressed shock wave releases from the free surface that contains surface defects. We present molecular dynamics (MD) simulations to investigate the ejecta production from tin surface shocked by supported and unsupported waves with pressures ranging from 8.5 to 60.8 GPa. It is found that the loading waveforms have little effect on spike velocity while remarkably affect the bubble velocity. The bubble velocity of unsupported shock loading remains nonzero constant value at late time as observed in experiments. Besides, the time evolution of ejected mass in the simulations is compared with the recently developed ejecta source model, indicating the suppressed ejection of unmelted or partial melted materials. Moreover, different reference positions are chosen to characterize the amount of ejecta under different loading waveforms. Compared with supported shock case, the ejected mass of unsupported shock case saturates at lower pressure. Through the analysis on unloading path, we find that the temperature of tin sample increases quickly from tensile stress state to zero pressure state, resulting in the melting of bulk tin under decaying shock. Thus, the unsupported wave loading exhibits a lower threshold pressure causing the solid-liquid phase transition on shock release than the supported shock loading.

  3. Molecular dynamics simulations of ejecta production from sinusoidal tin surfaces under supported and unsupported shocks

    Directory of Open Access Journals (Sweden)

    Bao Wu

    2018-04-01

    Full Text Available Micro-ejecta, an instability growth process, occurs at metal/vacuum or metal/gas interface when compressed shock wave releases from the free surface that contains surface defects. We present molecular dynamics (MD simulations to investigate the ejecta production from tin surface shocked by supported and unsupported waves with pressures ranging from 8.5 to 60.8 GPa. It is found that the loading waveforms have little effect on spike velocity while remarkably affect the bubble velocity. The bubble velocity of unsupported shock loading remains nonzero constant value at late time as observed in experiments. Besides, the time evolution of ejected mass in the simulations is compared with the recently developed ejecta source model, indicating the suppressed ejection of unmelted or partial melted materials. Moreover, different reference positions are chosen to characterize the amount of ejecta under different loading waveforms. Compared with supported shock case, the ejected mass of unsupported shock case saturates at lower pressure. Through the analysis on unloading path, we find that the temperature of tin sample increases quickly from tensile stress state to zero pressure state, resulting in the melting of bulk tin under decaying shock. Thus, the unsupported wave loading exhibits a lower threshold pressure causing the solid-liquid phase transition on shock release than the supported shock loading.

  4. Investigation of Surface Phenomena in Shocked Tin in Converging Geometry

    Energy Technology Data Exchange (ETDEWEB)

    Rousculp, Christopher L. [Los Alamos National Laboratory; Oro, David Michael [Los Alamos National Laboratory; Griego, Jeffrey Randall [Los Alamos National Laboratory; Turchi, Peter John [Los Alamos National Laboratory; Reinovsky, Robert Emil [Los Alamos National Laboratory; Bradley, Joseph Thomas [Los Alamos National Laboratory; Cheng, Baolian [Los Alamos National Laboratory; Freeman, Matthew Stouten [Los Alamos National Laboratory; Patten, Austin Randall [Los Alamos National Laboratory

    2016-03-21

    There is great interest in the behavior of the free surface of tin under shock loading. While it is known that meso-scale surface imperfections can seed the Richtmyer- Meshkov Instability (RMI) for a surface that is melted on release, much less is known about a tin surface that is solid, but plastically deforming. Here material properties such as shear and yield strength come into play especially in converging geometry. Previous experiments have been driven by direct contact HE. Usually a thin, flat target coupon is fielded with various single-mode, sinusoidal, machined, profiles on the free surface. The free surface is adjacent to either vacuum or an inert receiver gas. Most of these previous driver/target configurations have been nominal planer geometry. With modern HE it has been straightforward to shock tin into melt on release. However it has been challenging to achieve a low enough pressure for solid state on release. Here we propose to extend the existing base of knowledge to include the behavior of the free surface of tin in cylindrical converging geometry. By shock loading a cylindrical tin shell with a magnetically driven cylindrical liner impactor, the free surface evolution can be diagnosed with proton radiography. With the PHELIX capacitor bank, the drive can easily be varied to span the pressure range to achieve solid, mixed, and liquid states on release. A conceptual cylindrical liner and target is shown in Figure 1.

  5. Influence of edge conditions on material ejection from periodic grooves in laser shock-loaded tin

    Energy Technology Data Exchange (ETDEWEB)

    Rességuier, T. de; Roland, C. [Institut PPRIME, UPR 3346, CNRS, ENSMA, Université de Poitiers, 1 ave. Clément Ader, 86961 Futuroscope Cedex (France); Prudhomme, G.; Lescoute, E.; Mercier, P. [CEA, DAM, DIF, 91297 Arpajon (France); Loison, D. [Institut de Physique de Rennes, CNRS, Université de Rennes 1, 35042 Rennes (France)

    2016-05-14

    In a material subjected to high dynamic compression, the breakout of a shock wave at a rough free surface can lead to the ejection of high velocity debris. Anticipating the ballistic properties of such debris is a key safety issue in many applications involving shock loading, including pyrotechnics and inertial confinement fusion experiments. In this paper, we use laser driven shocks to investigate particle ejection from calibrated grooves of micrometric dimensions and approximately sinusoidal profile in tin samples, with various boundary conditions at the groove edges, including single groove and periodic patterns. Fast transverse shadowgraphy provides ejection velocities after shock breakout. They are found to depend not only on the groove depth and wavelength, as predicted theoretically and already observed in the past, but also, unexpectedly, on the edge conditions, with a jet tip velocity significantly lower in the case of a single groove than behind a periodic pattern.

  6. Crack propagation behavior of TiN coatings by laser thermal shock experiments

    International Nuclear Information System (INIS)

    Choi, Youngkue; Jeon, Seol; Jeon, Min-seok; Shin, Hyun-Gyoo; Chun, Ho Hwan; Lee, Youn-seoung; Lee, Heesoo

    2012-01-01

    Highlights: ► The crack propagation behavior of TiN coating after laser thermal shock experiment was observed by using FIB and TEM. ► Intercolumnar cracks between TiN columnar grains were predominant cracking mode after laser thermal shock. ► Cracks were propagated from the coating surface to the substrate at low laser pulse energy and cracks were originated at coating-substrate interface at high laser pulse energy. ► The cracks from the interface spread out transversely through the weak region of the columnar grains by repetitive laser shock. - Abstract: The crack propagation behavior of TiN coatings, deposited onto 304 stainless steel substrates by arc ion plating technique, related to a laser thermal shock experiment has been investigated using focused ion beam (FIB) and transmission electron microscopy (TEM). The ablated regions of TiN coatings by laser ablation system have been investigated under various conditions of pulse energies and number of laser pulses. The intercolumnar cracks were predominant cracking mode following laser thermal shock tests and the cracks initiated at coating surface and propagated in a direction perpendicular to the substrate under low loads conditions. Over and above those cracks, the cracks originated from coating-substrate interface began to appear with increasing laser pulse energy. The cracks from the interface also spread out transversely through the weak region of the columnar grains by repetitive laser shock.

  7. Temperature measurement of tin under shock compression

    International Nuclear Information System (INIS)

    Hereil, Pierre-Louis; Mabire, Catherine

    2002-01-01

    The results of pyrometric measurements performed at the interface of a tin target with a LiF window material are presented for stresses ranging from 38 to 55 GPa. The purpose of the study is to analyze the part of the interface in the temperature measurement by a multi-channel pyrometric device. The results show that the glue used at target/window interface remains transparent under shock. The values of temperature measured at the tin/LiF interface are consistent with the behavior of tin under shock

  8. Thermodynamically Based Equation of State for Shock Wave Studies : Application to the Design of Experiments on Tin

    International Nuclear Information System (INIS)

    Buy, Francois; Voltz, Christophe; Llorca, Fabrice

    2006-01-01

    This work is devoted to the evaluation of complex behavior of metals under shock wave loading. It presents a methodology for the design of specific experiments performed for validation of models and the evaluation of a multiphase equation of state for tin. This material has been selected because of the numerous works completed during the past years on its equation of state. We focus on the solid diagram which presents two solid phases. A thermodynamically based equation of state is developed which gives the opportunity to search for singularities which could be activated under particular shock wave loading. In the temperature -- pressure diagram, the superimposed Hugoniot and release paths make apparent a double shock, release shock configurations. We propose the design and the VISAR results of a calibrated shock -- reshock test for investigating the validity and the efficiency of the model for predicting the thermodynamical state of tin (phases mixing, temperature...). Comparison between numerical and experimental data shows the good accuracy of the results given by the EOS

  9. Mass-velocity and size-velocity distributions of ejecta cloud from shock-loaded tin surface using atomistic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Durand, O.; Soulard, L. [CEA, DAM, DIF, F-91297 Arpajon (France)

    2015-04-28

    The mass (volume and areal densities) versus velocity as well as the size versus velocity distributions of a shock-induced cloud of particles are investigated using large scale molecular dynamics simulations. A generic three-dimensional tin crystal with a sinusoidal free surface roughness (single wavelength) is set in contact with vacuum and shock-loaded so that it melts directly on shock. At the reflection of the shock wave onto the perturbations of the free surface, two-dimensional sheets/jets of liquid metal are ejected. The simulations show that the distributions may be described by an analytical model based on the propagation of a fragmentation zone, from the tip of the sheets to the free surface, in which the kinetic energy of the atoms decreases as this zone comes closer to the free surface on late times. As this kinetic energy drives (i) the (self-similar) expansion of the zone once it has broken away from the sheet and (ii) the average size of the particles which result from fragmentation in the zone, the ejected mass and the average size of the particles progressively increase in the cloud as fragmentation occurs closer to the free surface. Though relative to nanometric scales, our model may help in the analysis of experimental profiles.

  10. Use of IR pyrometry to measure free-surface temperatures of partially melted tin as a function of shock pressure

    International Nuclear Information System (INIS)

    Seifter, A.; Furlanetto, M. R.; Holtkamp, D. B.; Obst, A. W.; Payton, J. R.; Stone, J. B.; Tabaka, L. J.; Grover, M.; Macrum, G. S.; Stevens, G. D.; Turley, W. D.; Swift, D. C.; Veeser, L. R.

    2009-01-01

    Equilibrium equation of state theory predicts that the free-surface release temperature of shock-loaded tin will show a plateau at 505 K in the stress range from 19.5 to 33.0 GPa, corresponding to the solid-liquid, mixed-phase region of tin. In this paper we report free-surface temperature measurements on shock-loaded tin from 15 to 31 GPa using multiwavelength optical pyrometry. The shock waves were generated by direct contact of detonating high explosive with a tin sample, and the stress in the sample was determined by free-surface velocity measurements using photon Doppler velocimetry. We measured the emitted thermal radiance in the near IR region at four wavelengths from 1.5 to 5.0 μm. Above 25 GPa the measured free-surface temperatures were higher than the predicted 505 K, and they increased with increasing stress. This deviation may be explained by hot spots and/or variations in surface emissivity, and it may indicate a weakness in the use of a simple analysis of multiwavelength pyrometry data for conditions, such as above the melt threshold, where hot spots or emissivity variations may be significant. We are continuing to study the discrepancy to determine its cause.

  11. Release path temperatures of shock-compressed tin from dynamic reflectance and radiance measurements

    Energy Technology Data Exchange (ETDEWEB)

    La Lone, B. M., E-mail: lalonebm@nv.doe.gov; Stevens, G. D.; Turley, W. D. [National Security Technologies, LLC, Special Technologies Laboratory, Santa Barbara, California 93111 (United States); Holtkamp, D. B. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Iverson, A. J. [National Security Technologies, LLC, Los Alamos Operations, Los Alamos, New Mexico 87544 (United States); Hixson, R. S.; Veeser, L. R. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); National Security Technologies, LLC, Los Alamos Operations, Los Alamos, New Mexico 87544 (United States)

    2013-08-14

    Dynamic reflectance and radiance measurements were conducted for tin samples shock compressed to 35 GPa and released to 15 GPa using high explosives. We determined the reflectance of the tin samples glued to lithium fluoride windows using an integrating sphere with an internal xenon flashlamp as an illumination source. The dynamic reflectance (R) was determined at near normal incidence in four spectral bands with coverage in visible and near-infrared spectra. Uncertainties in R/R{sub 0} are <2%, and uncertainties in absolute reflectance are <5%. In complementary experiments, thermal radiance from the tin/glue/lithium fluoride interface was recorded with similar shock stress and spectral coverage as the reflectance measurements. The two sets of experiments were combined to obtain the temperature history of the tin surface with an uncertainty of <2%. The stress at the interface was determined from photonic Doppler velocimetry and combined with the temperatures to obtain temperature-stress release paths for tin. We discuss the relationship between the experimental release paths and release isentropes that begin on the principal shock Hugoniot.

  12. Dynamic fragmentation of laser shock-melted tin: experiment and modelling

    Energy Technology Data Exchange (ETDEWEB)

    De Resseguier, T. [CNRS ENSMA, Lab Combust and Deton, F-86961 Futuroscope (France); Signor, L.; Dragon, A. [CNRS ENSMA, Mecan and Phys Mat Lab, F-86961 Futuroscope (France); Signor, L.; Roy, G. [CEA Valduc, 21 - Is-sur-Tille (France)

    2010-07-01

    Dynamic fragmentation of shock-loaded metals is an issue of considerable importance for both basic science and a variety of technological applications, such as pyrotechnics or inertial confinement fusion, the latter involving high energy laser irradiation of thin metallic shells. Whereas spall fracture in solid materials has been extensively studied for many years, little data can be found yet about the evolution of this phenomenon after partial or full melting on compression or on release. Here, we present an investigation of dynamic fragmentation in laser shock-melted tin, from the 'micro-spall' process (ejection of a cloud of fine droplets) occurring upon reflection of the compressive pulse from the target free surface, to the late rupture observed in the un-spalled melted layer (leading to the formation of larger spherical fragments). Experimental results consist of time-resolved velocity measurements and post-shock observations of recovered targets and fragments. They provide original information regarding the loss of tensile strength associated with melting, the cavitation mechanism likely to occur in the melted metal, the sizes of the subsequent fragments and their ejection velocities. A theoretical description based on an energetic approach adapted to the case of a liquid metal is implemented as a failure criterion in a one-dimensional hydro-code including a multi-phase equation of state for tin. The resulting predictions of the micro-spall process are compared with experimental data. In particular, the use of a new experimental technique to quantify the fragment size distributions leads to a much better agreement with theory than previously reported. Finally, a complementary approach focused on cavitation is proposed to evaluate the role of this phenomenon in the fragmentation of the melted metal. (authors)

  13. Thermoluminescence of annealed and shock-loaded feldspar

    International Nuclear Information System (INIS)

    Hartmetz, C.P.

    1988-01-01

    Samples of oligoclase and bytownite were shock-loaded to a variety of pressures, and annealed for a variety of temperatures and times. The effect of Mrad doses of gamma-rays on oligoclase TL were also studied. After these treatments, thermoluminescence (TL) and X-ray diffraction (XRD) measurements were made to: (1) determine the effects of shock on terrestrial feldspar and compare with variations in the TL emission of ordinary chondrites (OCs); (2) determine if disordering in feldspar was responsible for any related changes in TL properties of OCs; (3) determine if the combined effect of shock plus annealing causes the changes in TL properties; (4) see if radiation damage from cosmic ray exposure plays a role in the TL variations; (5) examine the implications of this work to the thermal and shock histories of OCs. The lightly shock-loaded and annealed oligoclase samples have a dominant peak temperature of 120-140 C, identical to type 3.3-3.5 OCs. The heavily shocked samples dominant peak is at 230C, similar to type > 3.5 OCs . While the heavily annealed/disordered oligoclase samples have a peak at 280C, this peak is rarely observed in OCs. Radiation damage from Mrad doses of gamma-rays produced no change in peak temperature, but facilitated the shift to higher peak temperatures. The TL sensitivity of the shocked samples decreased by a factor of 25. Samples annealed at low temperatures (438-533C) showed a factor of 2 decrease in TL, but at the highest temperatures, the TL was a factor of 8 higher

  14. High-pressure phase transition in silicon carbide under shock loading using ultrafast x-ray diffraction

    Science.gov (United States)

    Tracy, S. J.; Smith, R. F.; Wicks, J. K.; Fratanduono, D. E.; Gleason, A. E.; Bolme, C.; Speziale, S.; Appel, K.; Prakapenka, V. B.; Fernandez Panella, A.; Lee, H. J.; MacKinnon, A.; Eggert, J.; Duffy, T. S.

    2017-12-01

    The behavior of silicon carbide (SiC) under shock loading was investigated through a series of time-resolved pump-probe x-ray diffraction (XRD) measurements. SiC is found at impact sites and has been put forward as a possible constituent in the proposed class of extra-solar planets known as carbon planets. Previous studies have used wave profile measurements to identify a phase transition under shock loading near 1 Mbar, but crystal structure information was not obtained. We have carried out an in situ XRD study of shock-compressed SiC using the Matter in Extreme Conditions instrument of the Linac Coherent Light Source. The femtosecond time resolution of the x-ray free electron laser allows for the determination of time-dependent atomic arrangements during shock loading and release. Two high-powered lasers were used to generate ablation-driven compression waves in the samples. Time scans were performed using the same drive conditions and nominally identical targets. For each shot in a scan, XRD data was collected at a different probe time after the shock had entered the SiC. Probe times extended up to 40 ns after release. Scans were carried out for peak pressures of 120 and 185 GPa. Our results demonstrate that SiC transforms directly from the ambient tetrahedrally-coordinated phase to the octahedral B1 structure on the nanosecond timescale of laser-drive experiments and reverts to the tetrahedrally coordinated ambient phase within nanoseconds of release. The data collected at 120 GPa exhibit diffraction peaks from both compressed ambient phase and transformed B1 phase, while the data at 185 GPa show a complete transformation to the B1 phase. Densities determined from XRD peaks are in agreement with an extrapolation of previous continuum data as well as theoretical predictions. Additionally, a high degree of texture was retained in both the high-pressure phase as well as on back transformation. Two-dimensional fits to the XRD data reveal details of the

  15. PDV-based estimation of high-speed ejecta particles density from shock-loaded tin plate

    Science.gov (United States)

    Franzkowiak, Jean-Eloi; Prudhomme, Gabriel; Mercier, Patrick; Lauriot, Séverine; Dubreuil, Estelle; Berthe, Laurent

    2017-06-01

    A machine-grooved metallic tin surface is explosively driven by a detonator with a shock-induced pressure of 25 GPa. The resulting dynamic fragmentation process called micro-jetting is the creation of high-speed jets of matter moving faster than the bulk metallic surface. The resulting fragmentation into micron-sized metallic particles generates a self-expanding cloud of droplets, whose areal mass, velocity and size distributions are unknown. Lithium-Niobate (LN) piezoelectric pin measured areal mass and Photonic Doppler Velocimetry (PDV) was employed to get a time-velocity spectrogram of the cloud. We present both experimental mass and velocity results and relate the integrated areal mass of the cloud to the PDV power spectral density under the assumption of a power law distribution for particle sizes. A model of PDV spectrograms is described, for which speckle fluctuations are averaged out. Finally, we use our model for a Maximum Likelihood Estimation of the cloud's parameters from PDV data. The integrated areal mass deduced from the PDV analysis is in good agreement with piezoelectric results. We underline the relevance of analyzing PDV data and correlating different diagnostics to retrieve the macro-physical properties of ejecta particles.

  16. Integrated microelectromechanical gyroscope under shock loads

    Science.gov (United States)

    Nesterenko, T. G.; Koleda, A. N.; Barbin, E. S.

    2018-01-01

    The paper presents a new design of a shock-proof two-axis microelectromechanical gyroscope. Without stoppers, the shock load enables the interaction between the silicon sensor elements. Stoppers were installed in the gyroscope to prevent the contact interaction between electrodes and spring elements with fixed part of the sensor. The contact of stoppers occurs along the plane, thereby preventing the system from serious contact stresses. The shock resistance of the gyroscope is improved by the increase in its eigenfrequency at which the contact interaction does not occur. It is shown that the shock load directed along one axis does not virtually cause the movement of sensing elements along the crosswise axes. Maximum stresses observed in the proposed gyroscope at any loading direction do not exceed the value allowable for silicon.

  17. Radiation- and pair-loaded shocks

    Science.gov (United States)

    Lyutikov, Maxim

    2018-06-01

    We consider the structure of mildly relativistic shocks in dense media, taking into account the radiation and pair loading, and diffusive radiation energy transfer within the flow. For increasing shock velocity (increasing post-shock temperature), the first important effect is the efficient energy redistribution by radiation within the shock that leads to the appearance of an isothermal jump, whereby the flow reaches the final state through a discontinuous isothermal transition. The isothermal jump, on scales much smaller than the photon diffusion length, consists of a weak shock and a quick relaxation to the isothermal conditions. Highly radiation-dominated shocks do not form isothermal jump. Pair production can mildly increase the overall shock compression ratio to ≈10 (4 for matter-dominated shocks and 7 of the radiation-dominated shocks).

  18. Deformation response of Zr after shock-loading

    International Nuclear Information System (INIS)

    Song, S.G.; Gray, G.T. III, and; Lopez, M.F.

    1996-01-01

    The post-shock stress-strain response and microstructural evolution of Zr shock-loaded to 7 GPa were investigated. A Bauschinger effect in the room temperature reload stress-strain behavior due to shock-loading has been observed following yielding. Deformation twinning is shown to play a more important role than slip during post-shock plastic deformation and work hardening. The work hardening rate of the shock-prestrained specimens is less temperature sensitive than that of annealed Zr. The underlying microstructures responsible for the Bauschinger effect and the differences in work hardening behavior are characterized. A new type of dense dislocation arrangement occurring during the shock-wave deformation of Zr is discussed. copyright 1996 American Institute of Physics

  19. Surface instabilities in shock loaded granular media

    Science.gov (United States)

    Kandan, K.; Khaderi, S. N.; Wadley, H. N. G.; Deshpande, V. S.

    2017-12-01

    The initiation and growth of instabilities in granular materials loaded by air shock waves are investigated via shock-tube experiments and numerical calculations. Three types of granular media, dry sand, water-saturated sand and a granular solid comprising PTFE spheres were experimentally investigated by air shock loading slugs of these materials in a transparent shock tube. Under all shock pressures considered here, the free-standing dry sand slugs remained stable while the shock loaded surface of the water-saturated sand slug became unstable resulting in mixing of the shocked air and the granular material. By contrast, the PTFE slugs were stable at low pressures but displayed instabilities similar to the water-saturated sand slugs at higher shock pressures. The distal surfaces of the slugs remained stable under all conditions considered here. Eulerian fluid/solid interaction calculations, with the granular material modelled as a Drucker-Prager solid, reproduced the onset of the instabilities as seen in the experiments to a high level of accuracy. These calculations showed that the shock pressures to initiate instabilities increased with increasing material friction and decreasing yield strain. Moreover, the high Atwood number for this problem implied that fluid/solid interaction effects were small, and the initiation of the instability is adequately captured by directly applying a pressure on the slug surface. Lagrangian calculations with the directly applied pressures demonstrated that the instability was caused by spatial pressure gradients created by initial surface perturbations. Surface instabilities are also shown to exist in shock loaded rear-supported granular slugs: these experiments and calculations are used to infer the velocity that free-standing slugs need to acquire to initiate instabilities on their front surfaces. The results presented here, while in an idealised one-dimensional setting, provide physical understanding of the conditions required to

  20. 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.

  1. PDV-based estimation of ejecta particles' mass-velocity function from shock-loaded tin experiment

    Science.gov (United States)

    Franzkowiak, J.-E.; Prudhomme, G.; Mercier, P.; Lauriot, S.; Dubreuil, E.; Berthe, L.

    2018-03-01

    A metallic tin plate with a given surface finish of wavelength λ ≃ 60 μm and amplitude h ≃ 8 μm is explosively driven by an electro-detonator with a shock-induced breakout pressure PSB = 28 GPa (unsupported). The resulting dynamic fragmentation process, the so-called "micro-jetting," is the creation of high-speed jets of matter moving faster than the bulk metallic surface. Hydrodynamic instabilities result in the fragmentation of these jets into micron-sized metallic particles constituting a self-expanding cloud of droplets, whose areal mass, velocity, and particle size distributions are unknown. Lithium-niobate-piezoelectric sensor measured areal mass and Photonic Doppler Velocimetry (PDV) was used to get a time-velocity spectrogram of the cloud. In this article, we present both experimental mass and velocity results and we relate the integrated areal mass of the cloud to the PDV power spectral density with the assumption of a power law particle size distribution. Two models of PDV spectrograms are described. The first one accounts for the speckle statistics of the spectrum and the second one describes an average spectrum for which speckle fluctuations are removed. Finally, the second model is used for a maximum likelihood estimation of the cloud's parameters from PDV data. The estimated integrated areal mass from PDV data is found to agree well with piezoelectric results. We highlight the relevance of analyzing PDV data and correlating different diagnostics to retrieve the physical properties of ejecta particles.

  2. Effect of annealing temperature on optical properties of binary zinc tin oxide nano-composite prepared by sol-gel route using simple precursors: structural and optical studies by DRS, FT-IR, XRD, FESEM investigations.

    Science.gov (United States)

    Habibi, Mohammad Hossein; Mardani, Maryam

    2015-02-25

    Binary zinc tin oxide nano-composite was synthesized by a facile sol-gel method using simple precursors from the solutions consisting of zinc acetate, tin(IV) chloride and ethanol. Effect of annealing temperature on optical and structural properties was investigated using X-ray diffraction (XRD), diffuse reflectance spectra (DRS), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD results revealed the existence of the ZnO and SnO2 phases. FESEM results showed that binary zinc tin oxide nano-composites ranges from 56 to 60 nm in diameter at 400°C and 500°C annealing temperatures respectively. The optical band gap was increased from 2.72 eV to 3.11 eV with the increasing of the annealing temperature. FTIR results confirmed the presence of zinc oxide and tin oxide and the broad absorption peaks at 3426 and 1602 cm(-1) can be ascribed to the vibration of absorptive water, and the absorption peaks at 546, 1038 and 1410 cm(-1) are due to the vibration of Zn-O or Sn-O groups in binary zinc tin oxide. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Investigation and evaluation of electron radiation damage on TiC and TiN protective coatings of Molybdenum for highly stressed first-wall components of fusion machines

    International Nuclear Information System (INIS)

    Wallura, E.; Hoven, H.; Koizlik, K.; Kny, E.

    1995-01-01

    The components of the plasma chamber of fusion reactors are subjected to the plasma wall interaction, a complex system of mechanical, thermal, and irradiation loadings. To investigate special modes of individual load processes (thermal shock, thermal fatigue, erosion) specific laboratory tests in an electron beam welding machine have been carried out. The materials Mo, Mo coated with TiC and with TiN, and bulk sintered TiC and TiN were examined in the tests. The 'post mortem' characterization of the material samples was done by secondary electron microscopy and metallography. One important aim was to determine critical loads as defined by the applied beam power density and the effective beam pulse duration, and to deduce from this load limit curves as a type of quantification of acceptable plasma wall interaction intensity. Below these load limits, Mo showed no induced material defects - neither in the uncoated nor in the coated quality. Above the critical heat load (100 MWm -2 ) severe melting occured in the surface of the uncoated as well as in the coated version - the TiC- and the TiN-coatings were completely eroded or vaporized in the molten crater. An influence of the coatings on the recrystallization of the Mo-melt was not detectable. Outside the molten area the coatings showed honeycombed cracking by thermal shock. In the case of bulk sintered TiC and TiN, marked thermal shock cracking appeared already after loadings with 10 MWm -2 and pulse duration of 0.1 sec. (author)

  4. Tolerance of Artemia to static and shock pressure loading

    Science.gov (United States)

    Fitzmaurice, B. C.; Appleby-Thomas, G. J.; Painter, J. D.; Ono, F.; McMillan, P. F.; Hazael, R.; Meersman, F.

    2017-10-01

    Hydrostatic and hydrodynamic pressure loading has been applied to unicellular organisms for a number of years due to interest from food technology and extremophile communities. There is also an emerging interest in the response of multicellular organisms to high pressure conditions. Artemia salina is one such organism. Previous experiments have shown a marked difference in the hatching rate of these organisms after exposure to different magnitudes of pressure, with hydrostatic tests showing hatching rates at pressures up to several GPa, compared to dynamic loading that resulted in comparatively low survival rates at lower pressure magnitudes. In order to begin to investigate the origin of this difference, the work presented here has focussed on the response of Artemia salina to (quasi) one-dimensional shock loading. Such experiments were carried out using the plate-impact technique in order to create a planar shock front. Artemia cysts were investigated in this manner along with freshly hatched larvae (nauplii). The nauplii and cysts were observed post-shock using optical microscopy to detect motility or hatching, respectively. Hatching rates of 18% were recorded at pressures reaching 1.5 GPa, as determined with the aid of numerical models. Subjecting Artemia to quasi-one-dimensional shock loading offers a way to more thoroughly explore the shock pressure ranges these organisms can survive.

  5. Synthesising highly reactive tin oxide using Tin(II2- ethylhexanoate polynucleation as precursor

    Directory of Open Access Journals (Sweden)

    Alejandra Montenegro Hernández

    2009-01-01

    Full Text Available Tin oxide is a widely used compound in technological applications, particularity as a catalyst, gas sensor and in making varistors, transparent conductors, electrocatalytic electrodes and photovoltaic cells. An ethylhexanoate tin salt, a carboxylic acid and poly-esterification were used for synthesising highly reactive tin oxide in the present study. Synthesis was controlled by Fourier transform infrared (FTIR spectroscopy and recording changes in viscosity. The tin oxide characteristics so obtained were determined using FTIR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM. The SnO2 dust synthesised and heat-treated at 550°C yielded high density aggregates, having greater than 50 μm particle size. This result demonstrates the high reactivity of the ceramic powders synthesised here.

  6. Lateral ring metal elastic wheel absorbs shock loading

    Science.gov (United States)

    Galan, L.

    1966-01-01

    Lateral ring metal elastic wheel absorbs practically all shock loading when operated over extremely rough terrain and delivers only a negligible shock residue to associated suspension components. The wheel consists of a rigid aluminum assembly to which lateral titanium ring flexible elements with treads are attached.

  7. Shear strength of shock-loaded polycrystalline tungsten

    International Nuclear Information System (INIS)

    Asay, J.R.; Chhabildas, L.C.; Dandekar, D.P.

    1980-01-01

    Previous experiments have suggested that tungsten undergoes a significant loss of shear strength when shock loaded to stresses greater than 7 GPa. In order to investigate this effect in more detail, a series of experiments was conducted in which polycrystalline tungsten was first shock loaded to approximately 10 GPa and then either unloaded or reloaded from the shocked state. Analysis of measured time-resolved wave profiles indicates that during initial compression to 9.7 GPa, the shear stress in polycrystalline tungsten increases to a maximum value of 1.1 GPA near a longitudinal stress of 5 GPa, but decreases to a final value of 0.8 GPa for stresses approaching 10 GPa. During reloading from a longitudinal stress of 9.7 GPa to a final value of approx.14 GPa, the shear stress increases to a peak value of 1.2 GPa and softens to 1.0 GPa in the final state. During unloading from the shocked state, the initial response is elastic with a strong Baushinger effect. Examination of a recovered sample shows evidence for both deformation slipping and twinning, which may be responsible for the observed softening

  8. Shock compression parameters for a boron-loaded, silicone-rubber composite

    International Nuclear Information System (INIS)

    Gust, W.H.; Van Thiel, M.; Gathers, G.R.

    1975-01-01

    Hugoniot parameters under uniaxial-shock-wave-loading from 0.03 to 0.6 Mbar are presented for a composite with 70 wt percent boron loaded in a silicone-rubber matrix. The plot of shock velocity vs particle velocity was found to be nonlinear. Equations that describe fits of the data are presented. (U.S.)

  9. Directly acting spring loaded safety valves as shock reducing measure

    International Nuclear Information System (INIS)

    Ismaier, A.; Schluecker, E.

    2010-01-01

    Hydraulic shocks as induced by fast closure of armatures or by sudden pump failures are massive impacts in piping systems and require extensive measures to absorb the generated load. Basically the avoidance of water hammers are preferable but in case of emergency shutdowns unavoidable hydraulic shocks have to be reduced by appropriate measures. The authors describe experiments with spring loaded safety valves as shock reducing measures. It was shown that the vale dimensions is essential for the efficacy. A realistic modeling is possible using the one-dimensional fluid mechanics code ROLAST.

  10. Delayed Failure in a Shock Loaded Alumina

    International Nuclear Information System (INIS)

    Cooper, G. A.; Millett, J. C. F.; Bourne, N. K.; Dandekar, D. P.

    2006-01-01

    Manganin stress gauges have been used to measure the lateral stress in a shock-loaded alumina. In combination with known longitudinal stresses, these have been used to determine the shear strength of this material, behind the shock front. The two-step nature of the lateral stress traces shows a slow moving front behind the main shock, behind which shear strength undergoes a significant decrease. Results also show that this front decreases markedly in velocity as the HEL is crossed, suggesting that limited plasticity occurs during inelastic deformation. Finally, comparison of measured shear strengths with other aluminas shows a high degree of agreement

  11. Interfacial Characteristics of TiN Coatings on SUS304 and Silicon Wafer Substrates with Pulsed Laser Thermal Shock

    International Nuclear Information System (INIS)

    Seo, Nokun; Jeon, Seol; Choi, Youngkue; Shin, Hyun-Gyoo; Lee, Heesoo; Jeon, Min-Seok

    2014-01-01

    TiN coatings prepared on different substrates that had different coefficients of thermal expansion were subjected to pulsed laser thermal shock and observed by using FIB milling to compare the deterioration behaviors. TiN coating on SUS304, which had a larger CTE (⁓17.3 × 10 - 6 /℃) than the coating was degraded with pores and cracks on the surface and showed significant spalling of the coating layer over a certain laser pulses. TiN coating on silicon wafer with a smaller CTE value, ⁓4.2 × 10‒6 /℃, than the coating exhibited less degradation of the coating layer at the same ablation condition. Cracks propagated at the interface were observed in the coating on the silicon wafer, which induced a compressive stress to the coating. The coating on the SUS304 showed less interface cracks while the tensile stress was applied to the coating. Delamination of the coating layer related to the intercolumnar cracks at the interface was observed in both coatings through bright-field TEM analysis.

  12. Crack density and electrical resistance in indium-tin-oxide/polymer thin films under cyclic loading

    KAUST Repository

    Mora Cordova, Angel; Khan, Kamran; El Sayed, Tamer

    2014-01-01

    Here, we propose a damage model that describes the degradation of the material properties of indium-tin-oxide (ITO) thin films deposited on polymer substrates under cyclic loading. We base this model on our earlier tensile test model and show

  13. Shock-induced spall in copper: the effects of anisotropy, temperature, loading pulse and defect

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Shengnian [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory; An, Qi [Los Alamos National Laboratory; Han, Li - Bo [USTC

    2009-07-28

    Shock-induced spall in Cu is investigated with molecular dynamics simulations. We examine spallation in initially perfect crystals and defective solids with grain boundaries (columnar bicrystals), stacking faults or vacancies, as well as the effect of temperature and loading pulses. Spall in single crystal Cu is anisotropic, and defects and high temperature may reduce the spall strength. Taylor-wave (triangular shock-release wave) loading is explored in comparison with square wave shock loading.

  14. Modeling dynamic beta-gamma polymorphic transition in Tin

    Science.gov (United States)

    Chauvin, Camille; Montheillet, Frank; Petit, Jacques; CEA Gramat Collaboration; EMSE Collaboration

    2015-06-01

    Solid-solid phase transitions in metals have been studied by shock waves techniques for many decades. Recent experiments have investigated the transition during isentropic compression experiments and shock-wave compression and have highlighted the strong influence of the loading rate on the transition. Complementary data obtained with velocity and temperature measurements around the polymorphic transition beta-gamma of Tin on gas gun experiments have displayed the importance of the kinetics of the transition. But, even though this phenomenon is known, modeling the kinetic remains complex and based on empirical formulations. A multiphase EOS is available in our 1D Lagrangian code Unidim. We propose to present the influence of various kinetic laws (either empirical or involving nucleation and growth mechanisms) and their parameters (Gibbs free energy, temperature, pressure) on the transformation rate. We compare experimental and calculated velocities and temperature profiles and we underline the effects of the empirical parameters of these models.

  15. Study on the removal of iron impurities in methanesulfonic acid tin plating bath

    Science.gov (United States)

    Hou-li, LIU; Jian-Jun, CHEN; Hong-Liang, PAN

    2018-03-01

    This thesis investigated the the influence of sodium sulfite as reducing agent on the recovery rate of tin ion. The approach is that HZ016 type cation exchange resin was used to adsorb Sn2+ and Fe2+ in electroplated tin solution first. After adsorption, the resin was removed by sulfuric acid, which was added with NaOH to adjust pH value to form precipitation and separate tin. X-ray diffraction (XRD) and energy spectrum (EDS) method were used to analyze the composition of the precipitates adjusted by pH. The results show that when the mass ratio of resin to bath is 1:2, the adsorption efficiency of resin reaches 98.3% and 97.1% respectively, and the elution efficiency of tin and iron reaches 95.1% and 94% respectively when the mass ratio of resin to eluent sulfuric acid is 1:4. Sodium sulfite was added to increase the efficiency of tin recovery by 8.1%. EDS and XRD atlas showed that after pH regulation, the main composition of the filtration precipitation was the hydroxides of tin.

  16. Spallation in NiTi under One-Dimensional Shock Loading

    International Nuclear Information System (INIS)

    Wallwork, A.; Workman, A.; Meziere, Y. J. E.; Millett, J. C. F.; Bourne, N. K.

    2006-01-01

    The dynamic response of the shape memory alloy NiTi has been of interest to a number of investigators because it displays a shape memory effect. The dynamic tensile (spall) strength of this material is measured under one-dimensional shock loading. The loading stress pulse length and impact stress were varied to a peak stress of 15 GPa. The pull back stress (σpbs) was found to increase with the applied pulse length. This suggests that the dynamic tensile strength is dependent upon the generation of a deformation micro structure that evolves behind the shock front. In contrast, increasing stress levels result in a near-constant pull back stress, although at the lowest applied stress, spallation did not occur

  17. Dynamic strength behavior of a Zr-based bulk metallic glass under shock loading

    International Nuclear Information System (INIS)

    Yu Yu-Ying; Xi Feng; Dai Cheng-Da; Cai Ling-Cang; Tan Ye; Li Xue-Mei; Wu Qiang; Tan Hua

    2015-01-01

    Dynamic strength behavior of Zr 51 Ti 5 Ni 10 Cu 25 Al 9 bulk metallic glass (BMG) up to 66 GPa was investigated in a series of plate impact shock-release and shock-reload experiments. Particle velocity profiles measured at the sample/LiF window interface were used to estimate the shear stress, shear modulus, and yield stress in shocked BMG. Beyond confirming the previously reported strain-softening of shear stress during the shock loading process for BMGs, it is also shown that the softened Zr-BMG still has a high shear modulus and can support large yield stress when released or reloaded from the shocked state, and both the shear modulus and the yield stress appear as strain-hardening behaviors. The work provides a much clearer picture of the strength behavior of BMGs under shock loading, which is useful to comprehensively understand the plastic deformation mechanisms of BMGs. (paper)

  18. Tribological characterization of TiN coatings prepared by magnetron sputtering

    Science.gov (United States)

    Makwana, Nishant S.; Chauhan, Kamlesh V.; Sonera, Akshay L.; Chauhan, Dharmesh B.; Dave, Divyeshkumar P.; Rawal, Sushant K.

    2018-05-01

    Titanium nitride (TiN) coating deposited on aluminium and brass pin substrates using RF reactive magnetron sputtering. The structural properties and surface morphology were characterized by X-ray diffraction (XRD), atomic force microscope (AFM) and field emission scanning electron microscope (FE-SEM). There was formation of (101) Ti2N, (110) TiN2 and (102) TiN0.30 peaks at 3.5Pa, 2Pa and 1.25Pa sputtering pressure respectively. The tribological properties of coating were inspected using pin on disc tribometer equipment. It was observed that TiN coated aluminium and brass pins demonstrated improved wear resistance than uncoated aluminium and brass pins.

  19. Characterization of tin oxide nanoparticles synthesized via oxidation from metal

    International Nuclear Information System (INIS)

    Abruzzi, R.C.; Dedavid, B.A.; Pires, M.J.R.; Streicher, M.

    2014-01-01

    The tin oxide (SnO_2) is a promising material with great potential for applications such as gas sensors and catalysts. This oxide nanostructures show higher activation efficiency due to its larger effective surface. This paper presents the synthesis and characterization of the tin oxide in different conditions, via oxidation of pure tin with nitric acid. Results obtained from the characterization of SnO_2 powder by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), Particle size by Dynamic Light Scattering (DLS) and Infrared Spectroscopy (FTIR) indicated that the conditions were suitable for the synthesis to obtain manometric tin oxide granules with crystalline structure of rutile. (author)

  20. Powder-XRD and (14) N magic angle-spinning solid-state NMR spectroscopy of some metal nitrides.

    Science.gov (United States)

    Kempgens, Pierre; Britton, Jonathan

    2016-05-01

    Some metal nitrides (TiN, ZrN, InN, GaN, Ca3 N2 , Mg3 N2 , and Ge3 N4 ) have been studied by powder X-ray diffraction (XRD) and (14) N magic angle-spinning (MAS) solid-state NMR spectroscopy. For Ca3 N2 , Mg3 N2 , and Ge3 N4 , no (14) N NMR signal was observed. Low speed (νr  = 2 kHz for TiN, ZrN, and GaN; νr  = 1 kHz for InN) and 'high speed' (νr  = 15 kHz for TiN; νr  = 5 kHz for ZrN; νr  = 10 kHz for InN and GaN) MAS NMR experiments were performed. For TiN, ZrN, InN, and GaN, powder-XRD was used to identify the phases present in each sample. The number of peaks observed for each sample in their (14) N MAS solid-state NMR spectrum matches perfectly well with the number of nitrogen-containing phases identified by powder-XRD. The (14) N MAS solid-state NMR spectra are symmetric and dominated by the quadrupolar interaction. The envelopes of the spinning sidebands manifold are Lorentzian, and it is concluded that there is a distribution of the quadrupolar coupling constants Qcc 's arising from structural defects in the compounds studied. Copyright © 2015 John Wiley & Sons, Ltd.

  1. UV-visible spectroscopic estimation of photodegradation of rhodamine-B dye using tin(IV) oxide nanoparticles.

    Science.gov (United States)

    Sangami, G; Dharmaraj, N

    2012-11-01

    Nanocrystalline, tin(IV) oxide (SnO(2)) particles has been prepared by thermal decomposition of tin oxalate precursor obtained from the reactions of tin(IV) chloride and sodium oxalate using eggshell membrane (ESM). The as-prepared SnO(2) nanoparticles were characterized by thermal studies, transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Raman, FT-IR and UV-visible studies and used as a photocatalyst for the degradation of rhodamine-B (Rh-B) dye. The size of the prepared nanoparticles was in the range of 5-12nm as identified from the TEM images. Powder XRD data revealed the presence of a tetragonal, rutile crystalline phase of the tin(IV) oxide nanoparticles. Thermal analysis showed that the decomposition of tin oxalate precursor to yield the titled tin(IV) oxide nanoparticles was completed below 500°C. The extent of degradation of Rh-B in the presence of SnO(2) monitored by absorption spectral measurements demonstrated that 94.48% of the selected dye was degraded upon irradiation with UV light for 60 min. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Prediction of crack density and electrical resistance changes in indium tin oxide/polymer thin films under tensile loading

    KAUST Repository

    Mora Cordova, Angel; Khan, Kamran; El Sayed, Tamer

    2014-01-01

    We present unified predictions for the crack onset strain, evolution of crack density, and changes in electrical resistance in indium tin oxide/polymer thin films under tensile loading. We propose a damage mechanics model to quantify and predict

  3. A microstructural investigation of shock-loading effects in FCC materials

    Science.gov (United States)

    Rohatgi, Aashish

    A systematic investigation of the influence of stacking fault energy (SFE) on shock loading effects in Cu and Cu-Al alloys has been conducted. Shock deformation in many materials is known to produce dislocation density in excess of that produced by quasi-static deformation to an equivalent strain. If the shock pressure is high enough and/or the SFE of the material is low enough, shock loading may also generate deformation twins. Both dislocations and deformation twins contribute to the post-shock strength of the material. Cu and a series of Cu-Al alloys with increasing Al contents were shock deformed at pressures of 10 and 35 GPa with a pulse duration of 1 mus each. The materials showed shock-strengthening which decreased with decreasing SFE. The twin component of post-shock strength was found to increase with decreasing SFE, while the dislocation component concurrently decreased. Since slip and twinning are competing phenomena, a greater propensity for twinning at lower SFE results in the shock-strain in low SFE materials being accommodated preferentially by twinning than by slip. Thus, the dislocation density in a twinned material is lower than if the deformation was accommodated entirely by slip. Additionally, as low SFE hinders cross-slip, a low SFE material shows a large Bauschinger effect and is unable to store additional dislocation line-length resulting in a lower dislocation density than in a similarly deformed high SFE material. The stored energy of materials shock-deformed to the same peak shock pressure was measured using differential scanning calorimetry (DSC) and was found to decrease with decreasing SFE. Using the stored energy data and a known value of energy per unit length of a dislocation, the stored dislocation density was found to decrease with decreasing SFE. It is suggested that the deformation twin boundaries are not as effective strengtheners, as dislocation-dislocation interactions. As a result of the lower strengthening efficiency but a

  4. Determination of babbit mechanical properties based on tin under static and cyclic loading

    Science.gov (United States)

    Zernin, M. V.

    2018-03-01

    Based on the results of studies of babbitt on the basis of tin under static loading under three types of stress state, the parameters of the criterion for the equivalence of stressed states were refined and a single diagram of the babbitt deformation was obtained. It is shown that the criterion of equivalence for static loading should contain the first principal stress and stress intensity. With cyclic loading, the first main voltage can be used as a criterion. The stages of development of fatigue cracks are described and it is logical to use a statistical approach to reveal the boundary of the transition from short cracks to macrocracks, based on a significant difference in the characteristics of the dispersion of the crack speeds at these two stages. The results of experimental studies of the cyclic crack resistance of babbitt are presented and the parameters of this boundary are obtained.

  5. Longitudinal and Lateral Stress Measurements in NiTi under One-Dimensional Shock Loading

    International Nuclear Information System (INIS)

    Meziere, Y. J. E.; Millett, J. C. F.; Bourne, N. K.; Wallwork, A.; Workman, A.

    2006-01-01

    This paper investigates the influence of the impact stress on the magnitude of the shear stress under one-dimensional shock loading. The shear stress is calculated from the measured longitudinal and the lateral stresses. New data in terms of shock stress, particle velocity and shock velocity has been gathered. Results indicate that the lateral stress has a positive dependence on the impact stress. A general decrease of the lateral stress was also observed immediately after the impact, while the longitudinal stress remains constant for the duration of the pulse length. This suggests that the shear strength increases behind the shock front. This decrease had been found to reach a constant value for the specimens impacted at lower stress. A complex mechanism of deformation behind the shock front during loading was thus reveals. This limit, related to the inflexion point noted on the Hugoniot (Us-up), seems to be an effect of the martensitic phase transformation undergoes by the material

  6. Shear Stress in Nickel and Ni-60Co under One-Dimensional Shock Loading

    International Nuclear Information System (INIS)

    Workman, A.; Wallwork, A.; Meziere, Y. J. E.; Millett, J. C. F.; Bourne, N. K.

    2006-01-01

    The dynamic response of pure nickel (Ni), and its alloy, Ni-60Co (by weight %), has been investigated during one-dimensional shock loading. Few materials' properties are different and the only significantly altered feature is the reduced stacking fault energy (SFE) for the Ni-60Co. This paper considers the effect of this reduced SFE on the shear strength. Data (in terms of shock stress, particle velocity and shock velocity) are also presented. The influence on the shear stress, τ of cobalt additions in nickel are then investigated and presented. Results indicate that the lateral stress is increasing in both materials with the increasing impact stress. The shear stress was found to be higher in the nickel than in the Ni-60Co. The progressive decrease of the lateral stress noted during loading indicates a complex mechanism of deformation behind the shock front

  7. Dynamic load synthesis for shock numerical simulation in space structure design

    Science.gov (United States)

    Monti, Riccardo; Gasbarri, Paolo

    2017-08-01

    Pyroshock loads are the most stressing environments that a space equipment experiences during its operating life from a mechanical point of view. In general, the mechanical designer considers the pyroshock analysis as a very demanding constraint. Unfortunately, due to the non-linear behaviour of the structure under such loads, only the experimental tests can demonstrate if it is able to withstand these dynamic loads. By taking all the previous considerations into account, some preliminary information about the design correctness could be done by performing ;ad-hoc; numerical simulations, for example via commercial finite element software (i.e. MSC Nastran). Usually these numerical tools face the shock solution in two ways: 1) a direct mode, by using a time dependent enforcement and by evaluating the time-response and space-response as well as the internal forces; 2) a modal basis approach, by considering a frequency dependent load and of course by evaluating internal forces in the frequency domain. This paper has the main aim to develop a numerical tool to synthetize the time dependent enforcement based on deterministic and/or genetic algorithm optimisers. In particular starting from a specified spectrum in terms of SRS (Shock Response Spectrum) a time dependent discrete function, typically an acceleration profile, will be obtained to force the equipment by simulating the shock event. The synthetizing time and the interface with standards numerical codes will be two of the main topics dealt with in the paper. In addition a congruity and consistency methodology will be presented to ensure that the identified time dependent loads fully match the specified spectrum.

  8. Structural, optical and electrical properties of tin oxide thin films for application as a wide band gap semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, Riti; Ahmad, Shabir; Aziz, Anver; Siddiqui, Azher Majid, E-mail: amsiddiqui@jmi.ac.in [Department of Physics, Jamia Millia Islamia, New Delhi-110025 (India)

    2015-08-28

    Tin oxide (SnO) thin films were synthesized using thermal evaporation technique. Ultra pure metallic tin was deposited on glass substrates using thermal evaporator under high vacuum. The thickness of the tin deposited films was kept at 100nm. Subsequently, the as-deposited tin films were annealed under oxygen environment for a period of 3hrs to obtain tin oxide films. To analyse the suitability of the synthesized tin oxide films as a wide band gap semiconductor, various properties were studied. Structural parameters were studied using XRD and SEM-EDX. The optical properties were studied using UV-Vis Spectrophotometry and the electrical parameters were calculated using the Hall-setup. XRD and SEM confirmed the formation of SnO phase. Uniform texture of the film can be seen through the SEM images. Presence of traces of unoxidised Sn has also been confirmed through the XRD spectra. The band gap calculated was around 3.6eV and the optical transparency around 50%. The higher value of band gap and lower value of optical transparency can be attributed to the presence of unoxidised Sn. The values of resistivity and mobility as measured by the Hall setup were 78Ωcm and 2.92cm{sup 2}/Vs respectively. The reasonable optical and electrical parameters make SnO a suitable candidate for optoelectronic and electronic device applications.

  9. Organic derivatives of tin (II/IV): Investigation of their structure

    Energy Technology Data Exchange (ETDEWEB)

    Szirtes, L., E-mail: szirtes@iki.kfki.h [Institute of Isotopes of the Hungarian Academy of Sciences, Budapest H-1525, P.O. Box 77 (Hungary); Megyeri, J., E-mail: megyeri@iki.kfki.h [Institute of Isotopes of the Hungarian Academy of Sciences, Budapest H-1525, P.O. Box 77 (Hungary); Kuzmann, E. [Laboratory of Nuclear Chemistry, CRC of the Hungarian Academy of Science at Eoetvoes University, H-1518 Budapest, P.O. Box 32 (Hungary); Beck, A. [Institute of Isotopes of the Hungarian Academy of Sciences, Budapest H-1525, P.O. Box 77 (Hungary)

    2011-07-15

    The structures of tin(II)-oxalate, tin(IV)Na-EDTA and tin(IV)Na{sub 8}-inositol hexaphosphate were investigated using XRD analysis. Samples were identified using the Moessbauer study, thermal analysis and FTIR spectrometry. The Moessbauer study determined two different oxidation states of tin atoms, and consequently two different tin surroundings in the end products. The tin oxalate was found to be orthorhombic with space group Pnma, a=9.2066(3) A, b=9.7590(1) A, c=13.1848(5) A, V=1184.62 A{sup 3} and Z=8. SnNa-EDTA was found to be monoclinic with space group P2{sub 1}/c{sub 1}, a=10.7544(3) A, b=10.1455(3) A, c=16.5130(6) A, {beta}=98.59(2){sup o}, V=1781.50(4) A{sup 3} and Z=4. Sn(C{sub 6}H{sub 6}Na{sub 8}O{sub 24}P{sub 6}) was found to be amorphous.

  10. Residual stress evolution regularity in thermal barrier coatings under thermal shock loading

    Directory of Open Access Journals (Sweden)

    Ximin Chen

    2014-01-01

    Full Text Available Residual stress evolution regularity in thermal barrier ceramic coatings (TBCs under different cycles of thermal shock loading of 1100°C was investigated by the microscopic digital image correlation (DIC and micro-Raman spectroscopy, respectively. The obtained results showed that, as the cycle number of the thermal shock loading increases, the evolution of the residual stress undergoes three distinct stages: a sharp increase, a gradual change, and a reduction. The extension stress near the TBC surface is fast transformed to compressive one through just one thermal cycle. After different thermal shock cycles with peak temperature of 1100°C, phase transformation in TBC does not happen, whereas the generation, development, evolution of the thermally grown oxide (TGO layer and micro-cracks are the main reasons causing the evolution regularity of the residual stress.

  11. Molecular dynamics simulation of shock-wave loading of copper and titanium

    Science.gov (United States)

    Bolesta, A. V.; Fomin, V. M.

    2017-10-01

    At extreme pressures and temperatures common materials form new dense phases with compacted atomic arrangements. By classical molecular dynamics simulation we observe that FCC copper undergo phase transformation to BCC structure. The transition occurs under shock wave loading at the pressures above 80 GPa and corresponding temperatures above 2000 K. We calculate phase diagram, show that at these pressures and low temperature FCC phase of copper is still stable and discuss the thermodynamic reason for phase transformation at high temperature shock wave regime. Titanium forms new hexagonal phase at high pressure as well. We calculate the structure of shock wave in titanium and observe that shock front splits in three parts: elastic, plastic and phase transformation. The possibility of using a phase transition behind a shock wave with further unloading for designing nanocrystalline materials with a reduced grain size is also shown.

  12. Thermodynamic parameters for mixtures of quartz under shock wave loading in views of the equilibrium model

    International Nuclear Information System (INIS)

    Maevskii, K. K.; Kinelovskii, S. A.

    2015-01-01

    The numerical results of modeling of shock wave loading of mixtures with the SiO 2 component are presented. The TEC (thermodynamic equilibrium component) model is employed to describe the behavior of solid and porous multicomponent mixtures and alloys under shock wave loading. State equations of a Mie–Grüneisen type are used to describe the behavior of condensed phases, taking into account the temperature dependence of the Grüneisen coefficient, gas in pores is one of the components of the environment. The model is based on the assumption that all components of the mixture under shock-wave loading are in thermodynamic equilibrium. The calculation results are compared with the experimental data derived by various authors. The behavior of the mixture containing components with a phase transition under high dynamic loads is described

  13. Tin electrodeposition from sulfate solution containing a benzimidazolone derivative

    Directory of Open Access Journals (Sweden)

    Said BAKKALI

    2016-11-01

    Full Text Available Tin electrodeposition in an acidic medium in the presence of N,N’-1,3-bis-[N-3-(6-deoxy-3-O-methyl-D-glucopyranose-6-yl-2-oxobenzimidazol-1-yl]-2-tetradecyloxypropane as an additive was investigated in this work. The adequate current density and the appropriate additive concentration were determined by gravimetric measurements. Chronopotentiometric curves showed that the presence of the additive caused an increase in the overpotential of tin reduction. The investigations by cyclic voltammetry technique revealed that, in the presence and in absence of the additive, there were two peaks, one in the cathodic side attributed to the reduction of Sn2+ and the other one in the anodic side assigned to the oxidation of tin previously formed during the cathodic scan. The surface morphology of the tin deposits was studied by scanning electron microscopy (SEM and XRD.

  14. Crack density and electrical resistance in indium-tin-oxide/polymer thin films under cyclic loading

    KAUST Repository

    Mora Cordova, Angel

    2014-11-01

    Here, we propose a damage model that describes the degradation of the material properties of indium-tin-oxide (ITO) thin films deposited on polymer substrates under cyclic loading. We base this model on our earlier tensile test model and show that the new model is suitable for cyclic loading. After calibration with experimental data, we are able to capture the stress-strain behavior and changes in electrical resistance of ITO thin films. We are also able to predict the crack density using calibrations from our previous model. Finally, we demonstrate the capabilities of our model based on simulations using material properties reported in the literature. Our model is implemented in the commercially available finite element software ABAQUS using a user subroutine UMAT.[Figure not available: see fulltext.].

  15. Experimental and numerical study of the micro-spalling of metallic targets subjected to laser shock

    International Nuclear Information System (INIS)

    Loison, D.

    2012-01-01

    Micro-spalling is a failure phenomenon consisting in dynamic fragmentation of a material after partial or full melting under intense shock wave loading. High power pulsed lasers are used as shock wave generators in laboratory for scientific and industrial purposes, such as research on inertial confinement fusion. In this context, the production of high velocity fragments can damage the facilities where shock experiments are conducted. This thesis, realized in collaboration with different teams from CEA, aims at understanding and modeling the different processes involved in micro-spalling phenomenon. Experiments to study micro-spalling of laser shock-loaded tin and aluminum targets have been performed. Various and complementary diagnostics (photonic Doppler velocimetry, soft recovery of debris and microtomography) have been used to characterize the ballistic properties (size distributions and velocities) of droplets constituting the micro-spalling cloud. In parallel, phase transition and fragmentation models have been adapted to simulate micro-spalling. These models have been implemented in a code to predict the sizes and velocities of debris. The combination of experimental and numerical results allows characterizing the successive stages of micro-spalling from laser-matter interaction to the ejection of droplets. (author)

  16. Formation of Ti-N graded bioceramic layer by DC hollow-cathode plasma nitriding

    Institute of Scientific and Technical Information of China (English)

    ZHENG Chuan-lin

    2004-01-01

    Ti-N graded ceramic layer was formed on titanium by using DC hollow-cathode plasma nitriding technique. The structure of Ti-N layer was analyzed using X-ray diffractometry(XRD) with Cu Kα radiation, and the microhardness( HV0.1) was measured from the surface to inner along the cross section of Ti-N layer. The results indicate that the Ti-N graded layer is composed of ε-Ti2 N, δ-TiN and α-Ti(N) phases. Mechanism discussion shows that hollow-cathode discharge can intensify gas ionization, increase current density and enhance the nitriding potential, which directly increases the thickness of the diffusion coatings compared with traditional nitriding methods.

  17. Elastic-plastic Fracture Mechanics Assessment of nozzle corners submitted to thermal shock loading

    International Nuclear Information System (INIS)

    Chapuliot, S.; Marie, S.

    2016-01-01

    This paper focuses on the development of a simplified analytical scheme for the elastic-plastic Fracture Mechanics Assessment of large nozzle corners. Within that frame, following the specific numerical effort performed for the definition of a Stress Intensity Factor compendium, complementary elastic-plastic developments are proposed here for the consideration of the thermal shock loading in the elastic-plastic domain: this type of loading is a major loading for massive structures such as nozzle corners of large components. Thus, an important numerical was performed in order to extend the applicability domain of existing analytical schemes to those complex geometries. The final formulation is a simple one, applicable to a large variety of materials and geometrical configurations as long as the structure is large and the defect remains small in comparison to the internal radius of the nozzle. - Highlights: • Fracture Mechanics Assessment of large nozzle corners. • Elastic-plastic Stress Intensity Factor determination under thermal shock loading. • Semi-analytical schemes for J calculation.

  18. Dynamic behavior of zirconium alloy E110 under submicrosecond shock-wave loading

    Directory of Open Access Journals (Sweden)

    Kazakov D.N.

    2015-01-01

    Full Text Available Stress waves have been measured under shock wave loading of zirconium alloy E110 samples with the 0.5 – 8 mm thickness at normal and elevated temperatures. Duration of shock loading pulses varied from ∼0.05 up to 1μs with the amplitude varying from 3.4 up to 23 GPa. Free-surface velocity profiles have been registered using VISAR and PDV interferometers with nanosecond resolution. Attenuation of the elastic precursor has been measured to determine plastic strain rate behind the elastic precursor front. The plastic strain rate was observed to decrease with propagation from 106 s−1 at the 0.46-mm distance down to 2 ⋅ 104 s−1 at the 8-mm distance. Spall strength has been measured under normal and elevated temperatures. Spall strength versus strain rate relationships have been constructed in the 105 s−1 – 106s−1 range. Under shock compression higher than 10.6 GPa, the three-wave configuration of the shock wave has been registered and the polymorphous α → ω transition is considered to be the reason of this phenomenon. This work was supported by State Atomic Energy Corporation “Rosatom” within State Contract # H.4x.44.90.13.1111

  19. Dynamic behavior of zirconium alloy E110 under submicrosecond shock-wave loading

    Science.gov (United States)

    Kazakov, D. N.; Kozelkov, O. E.; Mayorova, A. S.; Malyugina, S. N.; Mokrushin, S. S.; Pavlenko, A. V.

    2015-09-01

    Stress waves have been measured under shock wave loading of zirconium alloy E110 samples with the 0.5 - 8 mm thickness at normal and elevated temperatures. Duration of shock loading pulses varied from ˜0.05 up to 1μs with the amplitude varying from 3.4 up to 23 GPa. Free-surface velocity profiles have been registered using VISAR and PDV interferometers with nanosecond resolution. Attenuation of the elastic precursor has been measured to determine plastic strain rate behind the elastic precursor front. The plastic strain rate was observed to decrease with propagation from 106 s-1 at the 0.46-mm distance down to 2 ṡ 104 s-1 at the 8-mm distance. Spall strength has been measured under normal and elevated temperatures. Spall strength versus strain rate relationships have been constructed in the 105 s-1 - 106s-1 range. Under shock compression higher than 10.6 GPa, the three-wave configuration of the shock wave has been registered and the polymorphous α → ω transition is considered to be the reason of this phenomenon. This work was supported by State Atomic Energy Corporation "Rosatom" within State Contract # H.4x.44.90.13.1111

  20. The effects of defects on copper melting under hydrostatic and shock loading

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Shengnian [Los Alamos National Laboratory; An, Qi [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory; Han, Li - Bo [USTC

    2009-07-24

    With molecular dynamics (MD) simulations, we investigate the effects of defects on Cu melting under hydrostatic and shock wave loading. We explore preexistent defects including vacancies, stacking faults and grain boundaries, as well as shock-induced defects. Depending on defect characteristics (energy and concentration), defects may have negligible or considerable effects on melting at MD scales However, it is expected that defects have more pronounced effects at heating rates lower than the MD rates.

  1. Directly acting spring loaded safety valves as shock reducing measure; Direkt wirkende, federbelastete Sicherheitsventile als Druckstossreduzierende Massnahme

    Energy Technology Data Exchange (ETDEWEB)

    Ismaier, A.; Schluecker, E. [Erlangen-Nuernberg Univ. (DE). Lehrstuhl fuer Prozessmaschinen und Anlagentechnik (IPAT)

    2010-05-15

    Hydraulic shocks as induced by fast closure of armatures or by sudden pump failures are massive impacts in piping systems and require extensive measures to absorb the generated load. Basically the avoidance of water hammers are preferable but in case of emergency shutdowns unavoidable hydraulic shocks have to be reduced by appropriate measures. The authors describe experiments with spring loaded safety valves as shock reducing measures. It was shown that the vale dimensions is essential for the efficacy. A realistic modeling is possible using the one-dimensional fluid mechanics code ROLAST.

  2. Dynamic loads on human and animal surrogates at different test locations in compressed-gas-driven shock tubes

    Science.gov (United States)

    Alay, E.; Skotak, M.; Misistia, A.; Chandra, N.

    2018-01-01

    Dynamic loads on specimens in live-fire conditions as well as at different locations within and outside compressed-gas-driven shock tubes are determined by both static and total blast overpressure-time pressure pulses. The biomechanical loading on the specimen is determined by surface pressures that combine the effects of static, dynamic, and reflected pressures and specimen geometry. Surface pressure is both space and time dependent; it varies as a function of size, shape, and external contour of the specimens. In this work, we used two sets of specimens: (1) anthropometric dummy head and (2) a surrogate rodent headform instrumented with pressure sensors and subjected them to blast waves in the interior and at the exit of the shock tube. We demonstrate in this work that while inside the shock tube the biomechanical loading as determined by various pressure measures closely aligns with live-fire data and shock wave theory, significant deviations are found when tests are performed outside.

  3. Epitaxial integration of CoFe2O4 thin films on Si (001) surfaces using TiN buffer layers

    Science.gov (United States)

    Prieto, Pilar; Marco, José F.; Prieto, José E.; Ruiz-Gomez, Sandra; Perez, Lucas; del Real, Rafael P.; Vázquez, Manuel; de la Figuera, Juan

    2018-04-01

    Epitaxial cobalt ferrite thin films with strong in-plane magnetic anisotropy have been grown on Si (001) substrates using a TiN buffer layer. The epitaxial films have been grown by ion beam sputtering using either metallic, CoFe2, or ceramic, CoFe2O4, targets. X-ray diffraction (XRD) and Rutherford spectrometry (RBS) in random and channeling configuration have been used to determine the epitaxial relationship CoFe2O4 [100]/TiN [100]/Si [100]. Mössbauer spectroscopy, in combination with XRD and RBS, has been used to determine the composition and structure of the cobalt ferrite thin films. The TiN buffer layer induces a compressive strain in the cobalt ferrite thin films giving rise to an in-plane magnetic anisotropy. The degree of in-plane anisotropy depends on the lattice mismatch between CoFe2O4 and TiN, which is larger for CoFe2O4 thin films grown on the reactive sputtering process with ceramic targets.

  4. Characterization of Exoelectrogenic Bacteria Enterobacter Strains Isolated from a Microbial Fuel Cell Exposed to Copper Shock Load

    Science.gov (United States)

    Feng, Cuijie; Li, Jiangwei; Qin, Dan; Chen, Lixiang; Zhao, Feng; Chen, Shaohua; Hu, Hongbo; Yu, Chang-Ping

    2014-01-01

    Microorganisms capable of generating electricity in microbial fuel cells (MFCs) have gained increasing interest. Here fourteen exoelectrogenic bacterial strains were isolated from the anodic biofilm in an MFC before and after copper (Cu) shock load by Hungate roll-tube technique with solid ferric (III) oxide as an electron acceptor and acetate as an electron donor. Phylogenetic analysis of the 16S rRNA gene sequences revealed that they were all closely related to Enterobacter ludwigii DSM 16688T within the Enterobacteriaceae family, although these isolated bacteria showed slightly different morphology before and after Cu shock load. Two representative strains R2B1 (before Cu shock load) and B4B2 (after Cu shock load) were chosen for further analysis. B4B2 is resistant to 200 mg L−1 of Cu(II) while R2B1 is not, which indicated the potential selection of the Cu shock load. Raman analysis revealed that both R2B1 and B4B2 contained c-type cytochromes. Cyclic voltammetry measurements revealed that strain R2B1 had the capacity to transfer electrons to electrodes. The experimental results demonstrated that strain R2B1 was capable of utilizing a wide range of substrates, including Luria-Bertani (LB) broth, cellulose, acetate, citrate, glucose, sucrose, glycerol and lactose to generate electricity, with the highest current density of 440 mA·m−2 generated from LB-fed MFC. Further experiments indicated that the bacterial cell density had potential correlation with the current density. PMID:25412475

  5. Characterization of exoelectrogenic bacteria enterobacter strains isolated from a microbial fuel cell exposed to copper shock load.

    Directory of Open Access Journals (Sweden)

    Cuijie Feng

    Full Text Available Microorganisms capable of generating electricity in microbial fuel cells (MFCs have gained increasing interest. Here fourteen exoelectrogenic bacterial strains were isolated from the anodic biofilm in an MFC before and after copper (Cu shock load by Hungate roll-tube technique with solid ferric (III oxide as an electron acceptor and acetate as an electron donor. Phylogenetic analysis of the 16S rRNA gene sequences revealed that they were all closely related to Enterobacter ludwigii DSM 16688T within the Enterobacteriaceae family, although these isolated bacteria showed slightly different morphology before and after Cu shock load. Two representative strains R2B1 (before Cu shock load and B4B2 (after Cu shock load were chosen for further analysis. B4B2 is resistant to 200 mg L-1 of Cu(II while R2B1 is not, which indicated the potential selection of the Cu shock load. Raman analysis revealed that both R2B1 and B4B2 contained c-type cytochromes. Cyclic voltammetry measurements revealed that strain R2B1 had the capacity to transfer electrons to electrodes. The experimental results demonstrated that strain R2B1 was capable of utilizing a wide range of substrates, including Luria-Bertani (LB broth, cellulose, acetate, citrate, glucose, sucrose, glycerol and lactose to generate electricity, with the highest current density of 440 mA·m-2 generated from LB-fed MFC. Further experiments indicated that the bacterial cell density had potential correlation with the current density.

  6. Experimental design based response surface methodology optimization of ultrasonic assisted adsorption of safaranin O by tin sulfide nanoparticle loaded on activated carbon

    Science.gov (United States)

    Roosta, M.; Ghaedi, M.; Daneshfar, A.; Sahraei, R.

    2014-03-01

    In this research, the adsorption rate of safranine O (SO) onto tin sulfide nanoparticle loaded on activated carbon (SnS-NPAC) was accelerated by the ultrasound. SnS-NP-AC was characterized by different techniques such as SEM, XRD and UV-Vis measurements. The present results confirm that the ultrasound assisted adsorption method has remarkable ability to improve the adsorption efficiency. The influence of parameters such as the sonication time, adsorbent dosage, pH and initial SO concentration was examined and evaluated by central composite design (CCD) combined with response surface methodology (RSM) and desirability function (DF). Conducting adsorption experiments at optimal conditions set as 4 min of sonication time, 0.024 g of adsorbent, pH 7 and 18 mg L-1 SO make admit to achieve high removal percentage (98%) and high adsorption capacity (50.25 mg g-1). A good agreement between experimental and predicted data in this study was observed. The experimental equilibrium data fitting to Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models show that the Langmuir model is a good and suitable model for evaluation and the actual behavior of adsorption. Kinetic evaluation of experimental data showed that the adsorption processes followed well pseudo-second-order and intraparticle diffusion models.

  7. Effect of gas ratio on tribological properties of sputter deposited TiN coatings

    Energy Technology Data Exchange (ETDEWEB)

    Chavda, Mahesh R., E-mail: maheshchavda1990@gmail.com [Department of Mechanical Engineering, Dr. Jivraj Mehta Institute of Technology, Mogar-388340 (India); Chauhan, Kamlesh V.; Rawal, Sushant K., E-mail: sushantrawal.me@charusat.ac.in [CHAMOS Matrusanstha Department of Mechanical Engineering, Chandubhai S. Patel Institute of Technology, Charotar University of Science and Technology (CHARUSAT), Changa-388421 (India)

    2016-05-06

    Titanium nitride (TiN) coatings were deposited on Si, corning glass, pins of mild steel (MS, ϕ3mm), aluminium (Al, ϕ4mm) and brass (ϕ6mm) substratesby DC magnetron sputtering. The argon and nitrogen (Ar:N{sub 2})gas ratio was precisely controlled by Mass Flow Controller (MFC) and was varied systematically at diffract values of 10:10,12:08, 16:04 and 18:02sccm. The structural properties of TiN coatings were characterized by X-ray diffraction (XRD) and its surface topography was studied using field emission scanning electron microscopy (FE-SEM). The tribological properties of TiN coatings were investigated using pin-on-disc tribometer.

  8. Examining the effects of microstructure and loading on the shock initiation of HMX with mesoscale simulations

    Science.gov (United States)

    Springer, H. Keo; Tarver, Craig; Bastea, Sorin

    2015-06-01

    We perform reactive mesoscale simulations to study shock initiation in HMX over a range of pore morphologies and sizes, porosities, and loading conditions in order to improve our understanding of structure-performance relationships. These relationships are important because they guide the development of advanced macroscale models incorporating hot spot mechanisms and the optimization of novel energetic material microstructures. Mesoscale simulations are performed using the multiphysics hydrocode, ALE3D. Spherical, elliptical, polygonal, and crack-like pore geometries 0.1, 1, 10, and 100 microns in size and 2, 5, 10, and 14% porosity are explored. Loading conditions are realized with shock pressures of 6, 10, 20, 38, and 50 GPa. A Cheetah-based tabular model, including temperature-dependent heat capacity, is used for the unreacted and the product equation-of-state. Also, in-line Cheetah is used to probe chemical species evolution. The influence of microstructure and shock loading on shock-to-detonation-transition run distance, reaction rate and product gas species evolution are discussed. This work performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344. This work is funded by the Joint DoD-DOE Munitions Program.

  9. Nanotwin Formation in High-Manganese Austenitic Steels Under Explosive Shock Loading

    Science.gov (United States)

    Canadinc, D.; Uzer, B.; Elmadagli, M.; Guner, F.

    2018-04-01

    The micro-deformation mechanisms active in a high-manganese austenitic steel were investigated upon explosive shock loading. Single system of nanotwins forming within primary twins were shown to govern the deformation despite the elevated temperatures attained during testing. The benefits of nanotwin formation for potential armor materials were demonstrated.

  10. Martian Bow Shock and Magnetic Pile-Up Barrier Formation Due to the Exosphere Ion Mass-Loading

    Directory of Open Access Journals (Sweden)

    Eojin Kim

    2011-03-01

    Full Text Available Bow shock, formed by the interaction between the solar wind and a planet, is generated in different patterns depending on the conditions of the planet. In the case of the earth, its own strong magnetic field plays a critical role in determining the position of the bow shock. However, in the case of Mars of which has very a small intrinsic magnetic field, the bow shock is formed by the direct interaction between the solar wind and the Martian ionosphere. It is known that the position of the Martian bow shock is affected by the mass loading-effect by which the supersonic solar wind velocity becomes subsonic as the heavy ions originating from the planet are loaded on the solar wind. We simulated the Martian magnetosphere depending on the changes of the density and velocity of the solar wind by using the three-dimensional magnetohydrodynamic model built by modifying the comet code that includes the mass loading effect. The Martian exosphere model of was employed as the Martian atmosphere model, and only the photoionization by the solar radiation was considered in the ionization process of the neutral atmosphere. In the simulation result under the normal solar wind conditions, the Martian bow shock position in the subsolar point direction was consistent with the result of the previous studies. The three-dimensional simulation results produced by varying the solar wind density and velocity were all included in the range of the Martian bow shock position observed by Mariner 4, Mars 2, 3, 5, and Phobos 2. Additionally, the simulation result also showed that the change of the solar wind density had a greater effect on the Martian bow shock position than the change of the solar wind velocity. Our result may be useful in analyzing the future observation data by Martian probes.

  11. Refractive indices of CaF2 single crystals under elastic shock loading

    Science.gov (United States)

    Li, Y.; Zhou, X. M.; Liu, C. L.; Luo, S. N.

    2017-07-01

    Refractive indices and Hugoniots of CaF2 single crystals are investigated by laser displacement interferometry under shock loading below 5 GPa. Birefringence is observed for the [110] loading. We obtain the Hugoniot equation of states for [100], [110] and [111], and refractive indices for these orientations with consideration of their polarization. The measured refractive indices are in reasonable agreement with predictions based on the piezo-optic theory, and are used to refine the elasto-optic coefficients.

  12. Strong shock wave and areal mass oscillations associated with impulsive loading of planar laser targets

    International Nuclear Information System (INIS)

    Velikovich, A.L.; Schmitt, A.J.; Metzler, N.; Gardner, J.H.

    2003-01-01

    When a rippled surface of a planar target is irradiated with a short (subnanosecond) laser pulse, the shock wave launched into the target and the mass distribution of the shocked plasma will oscillate. These oscillations are found to be surprisingly strong compared, for example, to the case when the laser radiation is not turned off but rather keeps pushing the shock wave into the target. Being stronger than the areal mass oscillations due to ablative Richtmyer-Meshkov instability and feedout in planar targets, which have recently been observed at the Naval Research Laboratory (NRL) [Aglitskiy et al., Phys. Plasmas 9, 2264 (2002)], these oscillations should therefore be directly observable with the same diagnostic technique. Irradiation of a target with a short laser pulse represents a particular case of an impulsive loading, a fast release of finite energy in a thin layer near the surface of a target. Renewed interest to the impulsive loading in the area of direct-drive laser fusion is due to the recent proposals of using a short pulse prior to the drive pulse to make the target more resistant to laser imprint and Rayleigh-Taylor growth. Impulsive loading produces a shock wave that propagates into the target and is immediately followed by an expansion wave, which gradually reduces the shock strength. If the irradiated surface is rippled, then, while the shock wave propagates through the target, its modulation amplitude grows, exceeding the initial ripple amplitude by a factor of 2 or more. The oscillating areal mass reaches the peak values that exceed the initial mass modulation amplitude (density times ripple height) by a factor of 5-7 or more, and reverses its phase several times after the laser pulse is over. The oscillatory growth is more pronounced in fluids with higher shock compressibility and is probably related to the Vishniac's instability of a blast wave. Frequency of the oscillations is determined by the speed of sound in the shocked material, and

  13. Micro-X-ray diffraction assessment of shock stage in enstatite chondrites

    Science.gov (United States)

    Izawa, Matthew R. M.; Flemming, Roberta L.; Banerjee, Neil R.; McCausland, Philip J. A.

    2011-05-01

    A new method for assessing the shock stage of enstatite chondrites has been developed, using in situ micro-X-ray diffraction (μXRD) to measure the full width at half maximum (FWHMχ) of peak intensity distributed along the direction of the Debye rings, or chi angle (χ), corresponding to individual lattice reflections in two-dimensional XRD patterns. This μXRD technique differs from previous XRD shock characterization methods: it does not require single crystals or powders. In situ μXRD has been applied to polished thin sections and whole-rock meteorite samples. Three frequently observed orthoenstatite reflections were measured: (020), (610), and (131); these were selected as they did not overlap with diffraction lines from other phases. Enstatite chondrites are commonly fine grained, stained or darkened by weathering, shock-induced oxidation, and metal/sulfide inclusions; furthermore, most E chondrites have little olivine or plagioclase. These characteristics inhibit transmitted-light petrography, nevertheless, shock stages have been assigned MacAlpine Hills (MAC) 02837 (EL3) S3, Pecora Escarpment (PCA) 91020 (EL3) S5, MAC 02747 (EL4) S4, Thiel Mountains (TIL) 91714 (EL5) S2, Allan Hills (ALHA) 81021 (EL6) S2, Elephant Moraine (EET) 87746 (EH3) S3, Meteorite Hills (MET) 00783 (EH4) S4, EET 96135 (EH4-5) S2, Lewis Cliff (LEW) 88180 (EH5) S2, Queen Alexandra Range (QUE) 94204 (EH7) S2, LaPaz Icefield (LAP) 02225 (EH impact melt) S1; for the six with published shock stages, there is agreement with the published classification. FWHMχ plotted against petrographic shock stage demonstrates positive linear correlation. FWHMχ ranges corresponding to shock stages were assigned as follows: S1 3.5°, S6—not measured. Slabs of Abee (EH impact-melt breccia), and Northwest Africa (NWA) 2212 (EL6) were examined using μXRD alone; FWHMχ values place both in the S2 range, consistent with literature values. Micro-XRD analysis may be applicable to other shocked orthopyroxene

  14. Tin

    Science.gov (United States)

    Kamilli, Robert J.; Kimball, Bryn E.; Carlin, James F.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Tin (Sn) is one of the first metals to be used by humans. Almost without exception, tin is used as an alloy. Because of its hardening effect on copper, tin was used in bronze implements as early as 3500 B.C. The major uses of tin today are for cans and containers, construction materials, transportation materials, and solder. The predominant ore mineral of tin, by far, is cassiterite (SnO2).In 2015, the world’s total estimated mine production of tin was 289,000 metric tons of contained tin. Total world reserves at the end of 2016 were estimated to be 4,700,000 metric tons. China held about 24 percent of the world’s tin reserves and accounted for 38 percent of the world’s 2015 production of tin.The proportion of scrap used in tin production is between 10 and 25 percent. Unlike many metals, tin recycling is relatively efficient, and the fraction of tin in discarded products that get recycled is greater than 50 percent.Only about 20 percent of the world’s identified tin resources occur as primary hydrothermal hard-rock veins, or lodes. These lodes contain predominantly high-temperature minerals and almost invariably occur in close association with silicic, peraluminous granites. About 80 percent of the world’s identified tin resources occur as unconsolidated secondary or placer deposits in riverbeds and valleys or on the sea floor. The largest concentration of both onshore and offshore placers is in the extensive tin belt of Southeast Asia, which stretches from China in the north, through Thailand, Burma (also referred to as Myanmar), and Malaysia, to the islands of Indonesia in the south. Furthermore, tin placers are almost always found closely allied to the granites from which they originate. Other countries with significant tin resources are Australia, Bolivia, and Brazil.Most hydrothermal tin deposits belong to what can be thought of as a superclass of porphyry-greisen deposits. The hydrothermal tin deposits are all characterized by a close spatial

  15. A Comparative Study of the Behaviour of Five Dense Glass Materials Under Shock Loading Conditions

    Science.gov (United States)

    Radford, Darren D.; Proud, William G.; Field, John E.

    2001-06-01

    Previous work at the Cavendish Laboratory on the properties of glasses under shock loading has demonstrated that the material response is highly dependent upon the composition of the glass. The shock response of glass materials with an open structure, such as borosilicate, exhibits a ramping behaviour in the longitudinal stress histories due to structural collapse. Glass materials with a “filled” microstructure, as in the case of Type-D, Extra Dense Flint (DEDF) do not exhibit a ramping behaviour and behave in a manner similar to polycrystalline ceramics [1]. The current investigation compares the behaviour of five such glasses (SF15, DEDF, LACA, SF57 and DEDF-927210) under shock loading conditions. It is observed that slight changes in material composition can have a large affect on the inelastic behaviour. Principal Hugoniot and shear strength data are presented for all of the materials for pressures ranging from 2 to 14 GPa. Evidence of the so-called failure-front [2] is presented via lateral stress histories measured using manganin stress gauges and confirmed with high-speed photography. 1. Bourne, N.K., Millett, J.C.F., and Field, J.E., “On the strength of shocked glasses” Proc. R. Soc. Lond. A 455 (1999) 1275-1282 2. Brar, N.S., “Failure Waves in Glass and Ceramics Under Shock Compression”, in "Shock Compression of Condensed Matter 1999", ed. M.D. Furnish, L.C. Chhabildas, and R.S. Hixson, American Institute of Physics, Woodbury, New York, (1999) 601-606

  16. Dynamics of the aortic arch submitted to a shock loading: Parametric study with fluid-structure models.

    Science.gov (United States)

    El Baroudi, A; Razafimahery, F; Rakotomanana, L

    2012-01-01

    This work aims to present some fluid-structure models for analyzing the dynamics of the aorta during a brusque loading. Indeed, various lesions may appear at the aortic arch during car crash or other accident such as brusque falling. Aortic stresses evolution are simulated during the shock at the cross section and along the aorta. One hot question was that if a brusque deceleration can generate tissue tearing, or a shock is necessary to provoke such a damage. Different constitutive laws of blood are then tested whereas the aorta is assumed linear and elastic. The overall shock model is inspired from an experimental jig. We show that the viscosity has strong influence on the stress and parietal moments and forces. The nonlinear viscosity has no significant additional effects for healthy aorta, but modifies the stress and parietal loadings for the stenotic aorta.

  17. Outputs of shock-loaded small piezoceramic disks

    International Nuclear Information System (INIS)

    Charest, Jacques A.; Mace, Jonathan Lee

    2002-01-01

    Thin small-diameter polycrystalline Lead-Zirconate-Titanate piezoceramic disks were shock loaded in the D33 orientation over a stress range of 0.1-30 GPa. Their electrical outputs were discharged into 50 Ω viewing resistors, producing typically 0.15 μs quasi-triangular impulses ranging from 50-700 V. The gas gun flat plate impact approach and the high explosives (HE) plane wave lens approach were used to load piezoceramic elements. These piezoceramic elements consisted of 0.25 mm thick and 1.32 mm diameter disks that were ultrasonically machined from 25 mm piezocrystal disks of type APC 850, commercially produced by American Piezo Ceramic Inc. To facilitate our experiments, the piezoceramic elements were coaxially mounted at the tip of a 2.35 mm diameter brass tube, an arrangement that is commercialized by Dynasen, Inc. under the name Piezopin of model CA-1136. Simple calculations on the electrical outputs produced by these piezoceramic disks reveal electrical outputs in excess of 3000 W. Such short bursts of electrical energy have the potential for numerous applications where critical timing is needed to observe fast transient events

  18. Broad spectral response photodetector based on individual tin-doped CdS nanowire

    Directory of Open Access Journals (Sweden)

    Weichang Zhou

    2014-12-01

    Full Text Available High purity and tin-doped 1D CdS micro/nano-structures were synthesized by a convenient thermal evaporation method. SEM, EDS, XRD and TEM were used to examine the morphology, composition, phase structure and crystallinity of as-prepared samples. Raman spectrum was used to confirm tin doped into CdS effectively. The effect of impurity on the photoresponse properties of photodetectors made from these as-prepared pure and tin-doped CdS micro/nano-structures under excitation of light with different wavelength was investigated. Various photoconductive parameters such as responsivity, external quantum efficiency, response time and stability were analyzed to evaluate the advantage of doped nanowires and the feasibility for photodetector application. Comparison with pure CdS nanobelt, the tin-doped CdS nanowires response to broader spectral range while keep the excellect photoconductive parameters. Both trapped state induced by tin impurity and optical whispering gallery mode microcavity effect in the doped CdS nanowires contribute to the broader spectral response. The micro-photoluminescence was used to confirm the whispering gallery mode effect and deep trapped state in the doped CdS nanowires.

  19. The dynamic response and perturbation of magnetic field vector of orthotropic cylinders under various shock loads

    International Nuclear Information System (INIS)

    Dai, H.L.; Wang, X.

    2006-01-01

    In this paper, an analytical method is introduced to solve the problem for the dynamic stress-focusing and centred-effect of perturbation of the magnetic field vector in orthotropic cylinders under thermal and mechanical shock loads. Analytical expressions for the dynamic stresses and the perturbation of the magnetic field vector are obtained by means of finite Hankel transforms and Laplace transforms. The response histories of dynamic stresses and the perturbation of the field vector are also obtained. In practical examples, the dynamic focusing effect on both magnetoelastic stress and perturbation of the axial magnetic field vector in an orthotropic cylinder subjected to various shock loads is presented and discussed

  20. Numerical study on transonic shock oscillation suppression and buffet load alleviation for a supercritical airfoil using a microtab

    Directory of Open Access Journals (Sweden)

    Jinli Liu

    2016-01-01

    Full Text Available The effect of microtabs on shock oscillation suppression and buffet load alleviation for the National Aeronautics and Space Administration (NASA SC(2-0714 supercritical airfoil is studied. The unsteady flow field around the airfoil with a microtab is simulated with an unsteady Reynolds-averaged Navier–Stokes (URANS simulation method using the scale adaptive simulation-shear stress transport turbulence model. Firstly, the influence of the microtab installation position along the upper airfoil surface is investigated with respect to the buffet load and the characteristics of the unsteady flow field. The results show that the shock oscillating range and moving average speed decrease substantially when the microtab is installed in the middle region between the shock and trailing edges of the airfoil. Subsequently, the effects of the protruding height (0.50%, 0.75% and 1.00% of the chord length of the microtab (installed at x/c = 0.8 on the upper airfoil surface on the buffet load and flow field are studied, and the results show that the effect on buffet load alleviation is best when the protruding height of the microtab is 0.75% of the chord length. Finally, the mechanism of buffet load alleviation with the microtab on the upper airfoil surface is briefly discussed.

  1. Numerical simulation of shock absorbers heat load for semi-active vehicle suspension system

    Directory of Open Access Journals (Sweden)

    Demić Miroslav D.

    2016-01-01

    Full Text Available Dynamic simulation, based on modelling, has a significant role during to the process of vehicle development. It is especially important in the first design stages, when relevant parameters are to be defined. Shock absorber, as an executive part of a semi-active suspension system, is exposed to thermal loads which can lead to its damage and degradation of characteristics. Therefore, this paper attempts to analyze a conversion of mechanical work into heat energy by use of a method of dynamic simulation. The issue of heat dissipation from the shock absorber has not been taken into consideration.

  2. Study of the dynamic fragmentation of laser shock-loaded metallic target

    International Nuclear Information System (INIS)

    Lescoute, E.

    2010-01-01

    The irradiation of a metallic target by a high power laser pulse induces a shock wave in the material. Under some conditions, it leads to the production of high velocity ejecta which can damage the optical environment (lenses, mirrors, windows, etc.). With the ongoing development of high energy laser facilities designed to achieve inertial confinement fusion, such as the Laser MegaJoule in France or the National Ignition Facility in the USA, the question of debris ejection from metallic samples subjected to intense laser irradiation has become a key issue. It is necessary to understand fragmentation processes induced by laser shock, and to anticipate and quantify generated fragments, in order to design suitable protections and experiments, and to preserve laser facilities. The main fragmentation processes which can occur in a laser-shock-loaded metallic target and generate high velocity ejecta are: (i) micro-jetting, which occurs upon reflection of the incident compressive front from the free surface, (ii) spallation, which is due to the later interaction of the release wave reflected from that surface with the incident unloading wave and (iii) dynamic punching of thin targets. Experimental campaigns have been performed on high energy laser facilities in the Centre d'Etudes Scientifiques et Techniques d'Aquitaine (CESTA, CEA, Alise facility) and in the Laboratoire pour l'Utilisation des Lasers Intenses (LULI, Ecole Polytechnique, LULI 2000 facility). Gold and aluminium have been mainly studied because they are the two main metallic components of the target which will be used to achieved the inertial confinement fusion. Specific diagnostics have been developed and used during these experiments to study the dynamic fragmentation: transverse shadowgraphy, free surface velocity measurement and recovery of generated fragments. Experimental results have been compared with numerical predictions obtained with a bi-dimensional hydrodynamic code, where a specific numerical

  3. Diversity of Dominant Bacterial Taxa in Activated Sludge Promotes Functional Resistance following Toxic Shock Loading

    KAUST Repository

    Saikaly, Pascal; Oerther, Daniel B. Barton

    2010-01-01

    and functional resistance. In this system, activated sludge bacterial communities with higher biodiversity are functionally more resistant to disturbance caused by toxic shock loading. © 2010 Springer Science+Business Media, LLC.

  4. Investigation of Dynamic Friction Induced by Shock Loading Conditions

    International Nuclear Information System (INIS)

    Juanicotena, A.; Szarzynski, S.

    2006-01-01

    Modeling the frictional sliding of one surface against another under high pressure is often required to correctly describe the response of complex systems to shock loading. In order to provide data for direct code and model comparison, a new friction experiment investigating dry sliding characteristics of metal on metal at normal pressures up to 10 GPa and sliding velocities up to 400 m/s has been developed. The test consists of a specifically designed target made of two materials. A plane shock wave generated by plate impact results in one material sliding against the other. The material velocity of the rear surface of the target is recorded versus time by Doppler Laser Interferometry. The dynamic friction coefficient μ is then indirectly determined by comparison with results of numerical simulations involving the conventional Coulomb law. Using this new experimental configuration, three dynamic friction experiments were performed on AA 5083-Al (H111) / AISI 321 stainless steel tribo-pair. Results suggest a decrease in the friction coefficient with increasing sliding velocity

  5. Do running speed and shoe cushioning influence impact loading and tibial shock in basketball players?

    Directory of Open Access Journals (Sweden)

    Wing-Kai Lam

    2018-05-01

    Full Text Available Background Tibial stress fracture (TSF is a common injury in basketball players. This condition has been associated with high tibial shock and impact loading, which can be affected by running speed, footwear condition, and footstrike pattern. However, these relationships were established in runners but not in basketball players, with very little research done on impact loading and speed. Hence, this study compared tibial shock, impact loading, and foot strike pattern in basketball players running at different speeds with different shoe cushioning properties/performances. Methods Eighteen male collegiate basketball players performed straight running trials with different shoe cushioning (regular-, better-, and best-cushioning and running speed conditions (3.0 m/s vs. 6.0 m/s on a flat instrumented runway. Tri-axial accelerometer, force plate and motion capture system were used to determine tibial accelerations, vertical ground reaction forces and footstrike patterns in each condition, respectively. Comfort perception was indicated on a 150 mm Visual Analogue Scale. A 2 (speed × 3 (footwear repeated measures ANOVA was used to examine the main effects of shoe cushioning and running speeds. Results Greater tibial shock (P 0.14; η2 = 0.13. Discussion There may be an optimal band of shoe cushioning for better protection against TSF. These findings may provide insights to formulate rehabilitation protocols for basketball players who are recovering from TSF.

  6. Evaluation of the suitability of tin slag in cementitious materials: Mechanical properties and Leaching behaviour

    Science.gov (United States)

    Rustandi, Andi; Wafa' Nawawi, Fuad; Pratesa, Yudha; Cahyadi, Agung

    2018-01-01

    Tin slag, a by-product of tin production has been used in cementitious application. The present investigation focuses on the suitability of tin slag as primary component in cement and as component that substitute some amount of Portland Cement. The tin slags studied were taken from Bangka, Indonesia. The main contents of the tin slag are SiO2, Al2O3, and Fe2O3 according to the XRF investigation. The aim of this article was to study the mechanical behaviour (compressive strength), microstructure and leaching behaviour of tin slag blended cement. This study used air-cooled tin slag that had been passed through 400# sieve to replace Portland Cement with ratio 0, 10, 20, 30, 40 by weight. Cement pastes and tin slag blended cement pastes were prepared by using water/cement ratio (W/C) of 0.40 by weight and hydrated for various curing ages of 3, 7, 14 days The microstructure of the raw tin slag was investigated using Scanning Electron Microscope (SEM). The phase composition of each cement paste was investigated using X-ray Diffraction (XRD). The aim of the leachability test was to investigate the environmental impacts of tin slag blended cement product in the range 4-8 pH by using static pH-dependent leaching test. The result show that the increase of the tin slag content decreasing the mortar compressive strength at early ages. The use of tin slag in cement provide economic benefits for all related industries.

  7. Basic study on promotion of thawing frozen soil by shock loading

    Directory of Open Access Journals (Sweden)

    Toshiaki WATANABE

    2008-06-01

    Full Text Available The aim of study is to confirm a new technique that can crush the frozen soil and/or ice block using underwater shock wave generated by the underwater explosion of explosive. This technique can lead to the earlier sowing, which can have the larger harvest because the duration of sunshine increases. Especially, in Hokkaido prefecture, Japan, if the sowing is carried out in April, we can expect to have 150% of harvest in the ordinary season. In the case of small processing area such as road repairing, frozen soil is thawed by using the heat of gas burner and/or the electric heater. It is not a suitable plan to apply these heating methods to agriculture, from the point of view enormous amount of processing area. Thawing technique for frozen soil is effective against the cold regions, for example, Russia, Norway, and Sweden, etc. At first, we carried out experiments using a detonating fuse and ice block. The propagation process of shock wave into the ice block was observed by means of a high-speed camera. In order to check about that influence we tried to give an actual frozen soil a shock wave. We could get a result that existence of water layer serves an important role in promotion of thawing by the shock loading to the frozen soil.

  8. Shock loading predictions from application of indicial theory to shock-turbulence interactions

    Science.gov (United States)

    Keefe, Laurence R.; Nixon, David

    1991-01-01

    A sequence of steps that permits prediction of some of the characteristics of the pressure field beneath a fluctuating shock wave from knowledge of the oncoming turbulent boundary layer is presented. The theory first predicts the power spectrum and pdf of the position and velocity of the shock wave, which are then used to obtain the shock frequency distribution, and the pdf of the pressure field, as a function of position within the interaction region. To test the validity of the crucial assumption of linearity, the indicial response of a normal shock is calculated from numerical simulation. This indicial response, after being fit by a simple relaxation model, is used to predict the shock position and velocity spectra, along with the shock passage frequency distribution. The low frequency portion of the shock spectra, where most of the energy is concentrated, is satisfactorily predicted by this method.

  9. Effects of Annealing on TiN Thin Film Growth by DC Magnetron Sputtering

    Directory of Open Access Journals (Sweden)

    Azadeh Jafari

    2014-07-01

    Full Text Available We have reviewed the deposition of titanium nitride (TiN thin films on stainless steel substrates by a DC magnetron sputtering method and annealing at different annealing temperatures of 500, 600, and 700°C for 120 min in nitrogen/argon atmospheres. Effects of annealing temperatures on the structural and the optical properties of TiN films were investigated using X-ray diffraction (XRD, atomic force microscope (AFM, field emission scanning electron microscopy (FESEM, and UV-VIS spectrophotometer. Our experimental studies reveal that the annealing temperature appreciably affected the structures, crystallite sizes, and reflection of the films. By increasing the annealing temperature to 700°C crystallinity and reflection of the film increase. These results suggest that annealed TiN films can be good candidate for tokamak first wall due to their structural and optical properties.

  10. Hydrolysis of bis(dimethylamido)tin to tin (II) oxyhydroxide and its selective transformation into tin (II) or tin (IV) oxide

    KAUST Repository

    Khanderi, Jayaprakash; Shi, Lei; Rothenberger, Alexander

    2015-01-01

    Sn6O4(OH)4, a hydrolysis product of Sn(NMe2)2, is transformed to tin (II) or tin (IV) oxide by solid and solution phase processing. Tin (II) oxide is formed by heating Sn6O4(OH)4 at ≤200 °C in air or under inert atmosphere. Tin (IV) oxide

  11. Tin-oxide-coated single-walled carbon nanotube bundles supporting platinum electrocatalysts for direct ethanol fuel cells

    International Nuclear Information System (INIS)

    Hsu, Ryan S; Higgins, Drew; Chen Zhongwei

    2010-01-01

    Novel tin-oxide (SnO 2 )-coated single-walled carbon nanotube (SWNT) bundles supporting platinum (Pt) electrocatalysts for ethanol oxidation were developed for direct ethanol fuel cells. SnO 2 -coated SWNT (SnO 2 -SWNT) bundles were synthesized by a simple chemical-solution route. SnO 2 -SWNT bundles supporting Pt (Pt/SnO 2 -SWNTs) electrocatalysts and SWNT-supported Pt (Pt/SWNT) electrocatalysts were prepared by an ethylene glycol reduction method. The catalysts were physically characterized using TGA, XRD and TEM and electrochemically evaluated through cyclic voltammetry experiments. The Pt/SnO 2 -SWNTs showed greatly enhanced electrocatalytic activity for ethanol oxidation in acid medium, compared to the Pt/SWNT. The optimal SnO 2 loading of Pt/SnO 2 -SWNT catalysts with respect to specific catalytic activity for ethanol oxidation was also investigated.

  12. Tin-oxide-coated single-walled carbon nanotube bundles supporting platinum electrocatalysts for direct ethanol fuel cells.

    Science.gov (United States)

    Hsu, Ryan S; Higgins, Drew; Chen, Zhongwei

    2010-04-23

    Novel tin-oxide (SnO(2))-coated single-walled carbon nanotube (SWNT) bundles supporting platinum (Pt) electrocatalysts for ethanol oxidation were developed for direct ethanol fuel cells. SnO(2)-coated SWNT (SnO(2)-SWNT) bundles were synthesized by a simple chemical-solution route. SnO(2)-SWNT bundles supporting Pt (Pt/SnO(2)-SWNTs) electrocatalysts and SWNT-supported Pt (Pt/SWNT) electrocatalysts were prepared by an ethylene glycol reduction method. The catalysts were physically characterized using TGA, XRD and TEM and electrochemically evaluated through cyclic voltammetry experiments. The Pt/SnO(2)-SWNTs showed greatly enhanced electrocatalytic activity for ethanol oxidation in acid medium, compared to the Pt/SWNT. The optimal SnO(2) loading of Pt/SnO(2)-SWNT catalysts with respect to specific catalytic activity for ethanol oxidation was also investigated.

  13. A High-Purity Alumina for Use in Studies of Shock Loaded Samples

    Science.gov (United States)

    Lacina, David; Neel, Christopher

    2017-06-01

    We report the results of plate impact experiments on a potential new ``standard'' material, Coorstek Plasmapure-UC (99.9% purity) polycrystalline alumina, for use in non-conduction, impact environment, shock loading studies. This work was motivated by a desire to find a 99.9% purity alumina to replace the now unavailable Coors Vistal (99.9%) alumina, as it was hoped the Hugoniot elastic limit (HEL) of the new standard would match the 9-11 GPa value of Vistal. Shock response data, including the HEL, Hugoniot particle velocities, Hugoniot shock velocities, stress vs volume, and release wave speeds, was obtained up to 14 GPa. This data will be compared with Hugoniot curve data for other high purity alumina to contrast differences in the shock response, and is intended to be useful in impedance matching calculations. We will show that the HEL of Plasmapure-UC alumina is 5.5 GPa and speculate on causes for this lower than expected value. We will also explore why the elastic-plastic response for Plasmapure-UC alumina differs from what has been observed from other high purity alumina. The final result of this work is to recommend a well-characterized, lower purity alumina (Coorstek AD-995) as a potential new ``standard'' material.

  14. Corrosion Behavior of Carbon Steel in Concrete Material Composed of Tin Slag Waste in Aqueous Chloride Solution

    Science.gov (United States)

    Rustandi, Andi; Cahyadi, Agung; Taruli Siallagan, Sonia; Wafa' Nawawi, Fuad; Pratesa, Yudha

    2018-01-01

    Tin slag is a byproduct of tin ore smelting process which is rarely utilized. The main purpose of this work is to investigate the use of tin slag for concrete cement material application compared to the industrial Ordinary Portland Cement (OPC). Tin slag composition was characterized by XRD and XRF analysis. The characterization results showed the similar chemical composition of tin slag and OPC. It also revealed the semi crystalline structure of tin slag sample. Several electrochemical tests were performed to evaluate corrosion behavior of tin slag, OPC and various mixed composition of both materials and the addition of CaO. The corrosion behavior of OPC and tin slag were evaluated by using Cyclic Polarization, Electrochemical Impedance Spectroscopy (EIS) and Electrochemical Frequency Modulation (EFM) methods. Aqueous sodium chloride (NaCl) solution with 3.5% w.t concentration which similar to seawater was used as the electrolyte in this work. The steel specimen used as the reinforce bar (rebar) material of the concrete was carbon steel AISI 1045. The rebar was embedded in the concrete cement which composed of OPC and the various composition of tin slag including slag without addition of CaO and slag mixed with addition of 50 % CaO. The electrochemical tests results revealed that tin slag affected its corrosion behavior which becoming more active and increasing the corrosion rate as well as decreasing the electrochemical impedance.

  15. Variable flaw shape analysis for a reactor vessel under pressurized thermal shock loading

    International Nuclear Information System (INIS)

    Yang, C.Y.; Bamford, W.H.

    1984-01-01

    A study has been conducted to characterize the response of semi-elliptic surface flaws to thermal shock conditions which can result from safety injection actuation in nuclear reactor vessels. A methodology was developed to predict the behavior of a flaw during sample pressurized thermal shock events. The effects of a number of key variables on the flaw propagation were studied, including fracture toughness of the material and its gradient through the thickness, irradiation effects, effects of warm prestressing, and effects of the stainless steel cladding. The results of these studies show that under thermal shock loading conditions the flaw always tends to elongate along the vessel inside surface from the initial aspect ratio. However, the flaw shape always remains finite rather than becoming continuously long, as has often been assumed in earlier analyses. The final shape and size of the flaws were found to be rather strongly dependent on the effects of warm prestressing and the distribution of neutron flux. The improved methodology results in a more accurate and more realistic treatment of flaw shape changes during thermal shock events and provides the potential for quantifying additional margins for reactor vessel integrity analyses

  16. A contribution to the investigation of the heat load of shock absorbers of semi-active suspensions in motor vehicles

    Directory of Open Access Journals (Sweden)

    Miroslav D. Demić

    2013-10-01

    Full Text Available Dynamic simulation, based on modeling, has a significant role during the process of vehicle development. It is especially important in the first stages of vehicle design, when relevant vehicle parameters are to be defined. Shock absorbers as executive parts of vehicle semi-active suspension systems suffer thermal loads, which may result in damage and degradation of ther characteristics. Therefore,this paper shows an attempt to analyze converting of mechanical work into heat by using the dynamic simulation method. Introduction Shock absorbers are integral elements of semi-active suspension systems for vehicles (hereinafter SASS. They directly affect the active vehicle safety. The role of shock absorbers is to absorb mechanical vibrations transferred from the road and to ensure the safety of passengers in a vehicle. The kinetic energy of vehicle vibrations transforms into mechanical work or heat in shock absorbers. In practice, in the first stage of vehicle development, the shock absorber parameters are chosen from the condition of damping vibrations of vehicles, but their thermal shock loads should be also taken into account. Motor vehicles have complex dynamic characteristics manifested by spatial movement, parameters change during operation, a number of disturbing influences, backlash, friction, hysteresis, etc. The above-mentioned dynamic phenomena, especially vibration, lead to fatigue of driver and users, reduce the life of the vehicle and its systems, etc. The main objective of the system is to reduce the reliance of the above-mentioned negative effects, improving the vehicle behavior on the road and allow the exploitation of vehicles in a wide range of service conditions. Classical systems cannot satisfiy these conditions, so there was a need to introduce new suspension systems with controlled characteristics (briefly called "semi-active", or "active" systems. Oscillatory model of vehicle The differential equations of vibratory motion of

  17. Experimental studies on the deformation and rupture of thin metal plates subject to underwater shock wave loading

    Directory of Open Access Journals (Sweden)

    Chen Pengwan

    2015-01-01

    Full Text Available In this paper, the dynamic deformation and rupture of thin metal plates subject to underwater shock wave loading are studied by using high-speed 3D digital image correlation (3D-DIC. An equivalent device consist of a gas gun and a water anvil tube was used to supplying an exponentially decaying pressure in lieu of explosive detonation which acted on the panel specimen. The thin metal plate is clamped on the end of the shock tube by a flange. The deformation and rupture process of the metal plates subject to underwater shock waves are recorded by two high-speed cameras. The shape, displacement fields and strain fields of the metal plates under dynamic loading are obtained by using VIC-3D digital image correlation software. The strain gauges also were used to monitor the structural response on the selected position for comparison. The DIC data and the strain gauges results show a high level of correlation, and 3D-DIC is proven to be an effective method to measure 3D full-field dynamic response of structures under underwater impact loading. The effects of pre-notches on the failure modes of thin circular plate were also discussed.

  18. Prediction of crack density and electrical resistance changes in indium tin oxide/polymer thin films under tensile loading

    KAUST Repository

    Mora Cordova, Angel

    2014-06-11

    We present unified predictions for the crack onset strain, evolution of crack density, and changes in electrical resistance in indium tin oxide/polymer thin films under tensile loading. We propose a damage mechanics model to quantify and predict such changes as an alternative to fracture mechanics formulations. Our predictions are obtained by assuming that there are no flaws at the onset of loading as opposed to the assumptions of fracture mechanics approaches. We calibrate the crack onset strain and the damage model based on experimental data reported in the literature. We predict crack density and changes in electrical resistance as a function of the damage induced in the films. We implement our model in the commercial finite element software ABAQUS using a user subroutine UMAT. We obtain fair to good agreement with experiments. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  19. Temperature and pressure determination of the tin melt boundary from a combination of pyrometry, spectral reflectance, and velocity measurements along release paths

    Science.gov (United States)

    La Lone, Brandon; Asimow, Paul; Fatyanov, Oleg; Hixson, Robert; Stevens, Gerald

    2017-06-01

    Plate impact experiments were conducted on tin samples backed by LiF windows to determine the tin melt curve. Thin copper flyers were used so that a release wave followed the 30-40 GPa shock wave in the tin. The release wave at the tin-LiF interface was about 300 ns long. Two sets of experiments were conducted. In one set, spectral emissivity was measured at six wavelengths using a flashlamp illuminated integrating sphere. In the other set, thermal radiance was measured at two wavelengths. The emissivity and thermal radiance measurements were combined to obtain temperature histories of the tin-LiF interface during the release. PDV was used to obtain stress histories. All measurements were combined to obtain temperature vs. stress release paths. A kink or steepening in the release paths indicate where the releases merge onto the melt boundary, and release paths originating from different shock stresses overlap on the melt boundary. Our temperature-stress release path measurements provide a continuous segment of the tin melt boundary that is in good agreement with some of the published melt curves. This work was done by National Security Technologies, LLC, under Contract No. DE-AC52-06NA25946 with the U.S. Department of Energy, and supported by the Site-Directed Research and Development Program. DOE/NV/259463133.

  20. In-Situ Growth and Characterization of Indium Tin Oxide Nanocrystal Rods

    Directory of Open Access Journals (Sweden)

    Yan Shen

    2017-11-01

    Full Text Available Indium tin oxide (ITO nanocrystal rods were synthesized in-situ by a vapor-liquid-solid (VLS method and electron beam evaporation technique. When the electron-beam gun bombarded indium oxide (In2O3 and tin oxide (SnO2 mixed sources, indium and tin droplets appeared and acted as catalysts. The nanocrystal rods were in-situ grown on the basis of the metal catalyst point. The nanorods have a single crystal structure. Its structure was confirmed by X-ray diffraction (XRD and transmission electron microscopy (TEM. The surface morphology was analyzed by scanning electron microscopy (SEM. During the evaporation, a chemical process was happened and an In2O3 and SnO2 solid solution was formed. The percentage of doped tin oxide was calculated by Vegard’s law to be 3.18%, which was in agreement with the mixture ratio of the experimental data. The single crystal rod had good semiconductor switch property and its threshold voltage of single rod was approximately 2.5 V which can be used as a micro switch device. The transmission rate of crystalline nanorods ITO film was over 90% in visible band and it was up to 95% in the blue green band as a result of the oxygen vacancy recombination luminescence.

  1. Fuel-coolant interaction in a shock tube with initially-established film boiling

    International Nuclear Information System (INIS)

    Sharon, A.; Bankoff, S.G.

    1979-01-01

    A new mode of thermal interaction has been employed, in which liquid metal is melted in a crucible within a shock tube; the coolant level is raised to overflow the crucible and establish subcooled film boiling with known bulk metal temperature; and a pressure shock is then initiated. With water and lead-tin alloy an initial splash of metal may be obtained after the vapor film has collapsed, due primarily to thermal interaction, followed by a successive cycle of bubble growth and collapse. To obtain large interactions, the interfacial contact temperature must exceed the spontaneous nucleation temperature of the coolant. Other cutoff behavior is observed with respect to the initial system pressure and temperatures and with the shock pressure and rise time. Experiments with butanol and lead-tin alloy show only relatively mild interactions. Qualitative explanations are proposed for the different behaviors of the two liquids

  2. Characterization of tin oxide nanoparticles synthesized via oxidation from metal; Caracterizacao de nanoparticulas de oxido de estanho sintetizado via oxidacao do metal

    Energy Technology Data Exchange (ETDEWEB)

    Abruzzi, R.C.; Dedavid, B.A.; Pires, M.J.R.; Streicher, M., E-mail: afael.abruzzi@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Pos-Graduacao em Engenharia e Tecnologia de Materiais

    2014-07-01

    The tin oxide (SnO{sub 2}) is a promising material with great potential for applications such as gas sensors and catalysts. This oxide nanostructures show higher activation efficiency due to its larger effective surface. This paper presents the synthesis and characterization of the tin oxide in different conditions, via oxidation of pure tin with nitric acid. Results obtained from the characterization of SnO{sub 2} powder by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), Particle size by Dynamic Light Scattering (DLS) and Infrared Spectroscopy (FTIR) indicated that the conditions were suitable for the synthesis to obtain manometric tin oxide granules with crystalline structure of rutile. (author)

  3. Characterization of tin films synthesized from ethaline deep eutectic solvent

    International Nuclear Information System (INIS)

    Ghosh, Swatilekha; Roy, Sudipta

    2014-01-01

    Highlights: • Tin deposition was achieved by galvanostatic method on the basic substrates from ethaline deep eutectic solvent without use of any additives. • The current potential behaviour of tin system changes with increase in concentration of hydrated tin chloride in ethaline. • The deposition rate in ethaline display three times lower value compared to aqueous electrolytes. • Fine grained crystals of 62 ± 10 nm were obtained for tin deposits. • The deposition process is economical and can be adapted for industrial applications. - Abstract: Tin (Sn) films were electrodeposited by galvanostatic method from ethaline deep eutectic solvent (DES), without any additives. The effect of various deposition parameters on the microstructure was studied. With increase in metal salt concentration from 0.01 to 0.1 M, changes in current–potential behaviour were observed in the polarization scans. This might be due to the existence of [SnCl 3 ] − , [Sn 2 Cl 5 ] − complexes in ethaline DES. Smooth and homogeneous deposits were obtained on a steel substrate surface by applying current density of 1.57 × 10 −3 A/cm 2 at 25 °C. Under these conditions the deposition rate was found to be 0.1 ± 10% μm/min and current efficiency was obtained as 84 ± 3%. XRD analysis of the deposit confirmed the polycrystalline tetragonal structure with mostly (2 0 0) orientation having a crystallite size about 62 ± 16% nm along with an internal strain of 0.0031 ± 22%. The present deposition method is simple, economical and can be adapted for industrial applications

  4. Shock enhancement of cellular materials subjected to intensive pulse loading

    Science.gov (United States)

    Zhang, J.; Fan, J.; Wang, Z.; Zhao, L.; Li, Z.

    2018-03-01

    Cellular materials can dissipate a large amount of energy due to their considerable stress plateau, which contributes to their extensive applications in structural design for crashworthiness. However, in some experiments with specimens subjected to intense impact loads, transmitted stress enhancement has been observed, leading to severe damage to the objects protected. Transmitted stress through two-dimensional Voronoi cellular materials as a protective device is qualitatively studied in this paper. Dimensionless parameters of material properties and loading parameters are defined to give critical conditions for shock enhancement and clarify the correlation between the deformations and stress enhancement. The effect of relative density on this amplifying phenomenon is investigated as well. In addition, local strain fields are calculated by using the optimal local deformation gradient, which gives a clear presentation of deformations and possible local non-uniformity in the crushing process. This research provides valuable insight into the reliability of cellular materials as protective structures.

  5. Barrier experiment: Shock initiation under complex loading

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-01-12

    The barrier experiments are a variant of the gap test; a detonation wave in a donor HE impacts a barrier and drives a shock wave into an acceptor HE. The question we ask is: What is the trade-off between the barrier material and threshold barrier thickness to prevent the acceptor from detonating. This can be viewed from the perspective of shock initiation of the acceptor subject to a complex pressure drive condition. Here we consider key factors which affect whether or not the acceptor undergoes a shock-to-detonation transition. These include the following: shock impedance matches for the donor detonation wave into the barrier and then the barrier shock into the acceptor, the pressure gradient behind the donor detonation wave, and the curvature of detonation front in the donor. Numerical simulations are used to illustrate how these factors affect the reaction in the acceptor.

  6. Effect of microstructure of TiN film on properties as bipolar plate coatings in polymer electrolyte membrane fuel cell prepared by inductively coupled plasma assisted magnetron sputtering

    International Nuclear Information System (INIS)

    Feng, Kai; Li, Zhuguo

    2013-01-01

    As potential application in bipolar plate of polymer electrolyte membrane fuel cell, the microstructure, corrosion resistance and the electrical conductivity of titanium nitride (TiN) and Si doped titanium nitride (Ti 0.9 Si 0.1 N) films deposited by magnetron sputtering with different bias voltages are investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), electrochemical test and four-point probe method, respectively. XRD, SEM and AFM results reveal that the texture and topography of TiN film depend on the bias voltage and incorporation of Si. When the bias voltage is − 20 V and − 30 V, the TiN and Ti 0.9 Si 0.1 N films exhibit a dense (111) plane preferred growth, denser structure and smoother surface topography. The potentiodynamic test results indicate that the TiN and Ti 0.9 Si 0.1 N films have higher chemical inertness and better corrosion resistance. The films can satisfy the requirement of current density for bipolar plate materials. Incorporation of Si element into TiN film makes the passive current density more stable. Four-point probe measurement results show that the resistivity of both TiN and Ti 0.9 Si 0.1 N films reaches minimum when the deposition bias voltage is − 20 V. - Highlights: • Dense TiN and Ti 0.9 Si 0.1 N films are deposited by magnetron sputtering. • Preferred growth orientation of TiN depends on the bias voltage and Si doping. • TiN and Ti 0.9 Si 0.1 N films have excellent corrosion resistance. • Surface conductivity of TiN and Ti 0.9 Si 0.1 N films evolves with bias voltage

  7. Viscosity of aluminum under shock-loading conditions

    International Nuclear Information System (INIS)

    Ma Xiao-Juan; Liu Fu-Sheng; Zhang Ming-Jian; Sun Yan-Yun

    2011-01-01

    A reliable data treatment method is critical for viscosity measurements using the disturbance amplitude damping method of shock waves. In this paper the finite difference method is used to obtain the numerical solutions for the disturbance amplitude damping behaviour of the sinusoidal shock front in a flyer-impact experiment. The disturbance amplitude damping curves are used to depict the numerical solutions of viscous flow. By fitting the experimental data to the numerical solutions of different viscosities, we find that the effective shear viscosity coefficients of shocked aluminum at pressures of 42, 78 and 101 GPa are (1500±100) Pa·s, (2800±100) Pa·s and (3500±100) Pa·s respectively. It is clear that the shear viscosity of aluminum increases with an increase in shock pressure, so aluminum does not melt below a shock pressure of 101 GPa. This conclusion is consistent with the sound velocity measurement. (interdisciplinary physics and related areas of science and technology)

  8. 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

  9. 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.

  10. 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.

  11. Effect of effluent recycling and shock loading on the biodegradation of complex phenolic mixture in hybrid UASB reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ramakrishnan, A.; Gupta, S.K. [Indian Institute of Technology, Bombay (India)

    2008-06-15

    This study describes the feasibility of anaerobic treatment of synthetic coal wastewater using four identical 13.5 L (effective volume) bench scale hybrid up flow anaerobic sludge blanket (HUASB) reactors (R1, R2, R3 and R4) under mesophilic (27 {+-} 5{sup o}C) conditions. Synthetic coal wastewater with an average chemical oxygen demand (COD) of 2240 mg/L and phenolics concentration of 752 mg/L was used as substrate. Effluent recirculation was employed at four different effluent to feed recirculation ratios (R/F) of 0.5, 1.0, 1.5 and 2.0 for 100 days to study the effect of recirculation on the performance of the reactors. Phenolics and COD removal was found to improve with increase in effluent recirculation. An effluent to feed recycle ratio of 1.0 resulted in maximum removal of phenolics and COD. Phenolics and COD removal improved from 88% and 92% to 95% each, respectively. The concentration of volatile fatty acids in the effluent was lower than the influent when effluent to feed recirculation was employed. Effect of shock loading on the reactors revealed that phenolics shock load up to 2.5 times increase in the normal input phenolics concentration in the form of continuous shock load for 4 days did not affect the reactors performance irreversibly.

  12. Structural, optical and electrical properties of indium tin oxide thin films prepared by spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Benamar, E.; Rami, M.; Messaoudi, C.; Sayah, D.; Ennaoui, A. [Deptartmento de Physique, Laboratoire de Physique des Materiaux, Faculte des Sciences, BP 1014, Ave Inb Battouta, Rabat (Morocco)

    1998-11-27

    Spray pyrolysis process has been used to deposit highly transparent and conducting films of tin-doped indium oxide onto glass substrates. The electrical, structural and optical properties have been investigated as a function of various deposition parameters namely dopant concentrations, temperature and nature of substrate. The morphology of the surface as a function of the substrate temperature has been studied using atomic force microscopy. XRD has shown that deposited films are polycrystalline without second phases and have a preferred orientation (4 0 0). Indium tin oxide layers with low resistivity values around 4x10{sup -5} {Omega} cm and transmission coefficients in the visible and near-infrared range of about 85-90% have been easily obtained

  13. Effects of High-Humidity Aging on Platinum, Palladium, and Gold Loaded Tin Oxide—Volatile Organic Compound Sensors

    Directory of Open Access Journals (Sweden)

    Maiko Nishibori

    2010-07-01

    Full Text Available This study is an investigation of high-humidity aging effects on the total volatile organic compound (T–VOC gas-sensing properties of platinum, palladium, and gold-loaded tin oxide (Pt,Pd,Au/SnO2 thick films. The sensor responses of the high-humidity aged Pt,Pd,Au/SnO2, a non-aged Pt,Pd,Au/SnO2, and a high-humidity aged Pt/SnO2 to T–VOC test gas have been measured. The high-humidity aging is an effective treatment for resistance to humidity change for the Pt,Pd,Au/SnO2 but not effective for the Pt/SnO2. The mechanism of the high-humidity aging effects is discussed based on the change of surface state of the SnO2 particles.

  14. Synthesis and characterization of single-crystalline zinc tin oxide nanowires

    Science.gov (United States)

    Shi, Jen-Bin; Wu, Po-Feng; Lin, Hsien-Sheng; Lin, Ya-Ting; Lee, Hsuan-Wei; Kao, Chia-Tze; Liao, Wei-Hsiang; Young, San-Lin

    2014-05-01

    Crystalline zinc tin oxide (ZTO; zinc oxide with heavy tin doping of 33 at.%) nanowires were first synthesized using the electrodeposition and heat treatment method based on an anodic aluminum oxide (AAO) membrane, which has an average diameter of about 60 nm. According to the field emission scanning electron microscopy (FE-SEM) results, the synthesized ZTO nanowires are highly ordered and have high wire packing densities. The length of ZTO nanowires is about 4 μm, and the aspect ratio is around 67. ZTO nanowires with a Zn/(Zn + Sn) atomic ratio of 0.67 (approximately 2/3) were observed from an energy dispersive spectrometer (EDS). X-ray diffraction (XRD) and corresponding selected area electron diffraction (SAED) patterns demonstrated that the ZTO nanowire is hexagonal single-crystalline. The study of ultraviolet/visible/near-infrared (UV/Vis/NIR) absorption showed that the ZTO nanowire is a wide-band semiconductor with a band gap energy of 3.7 eV.

  15. Quantifying Cutting and Wearing Behaviors of TiN- and CrNCoated AISI 1070 Steel

    Directory of Open Access Journals (Sweden)

    Ahmet Cakan

    2008-11-01

    Full Text Available Hard coatings such as titanium nitride (TiN and chromium nitride (CrN are widely used in cutting and forming tools against wear and corrosion. In the present study, hard coating films were deposited onto AISI 1070 steels by a cathodic arc evaporation plating (CAVP technique. These samples were subjected to wear in a conventional lathe for investigating the tribological behaviour of coating structure, and prenitrided subsurface composition was characterized using scanning electron microscopy (SEM, line scan analyses and X-ray diffraction (XRD. The wear properties of TiN- and CrNcoated samples were determined using an on-line monitoring system. The results show that TiN-coated samples demonstrate higher wear resistance than CrN-coated samples.

  16. Strength of shock-loaded single-crystal tantalum [100] determined using in situ broadband x-ray Laue diffraction.

    Science.gov (United States)

    Comley, A J; Maddox, B R; Rudd, R E; Prisbrey, S T; Hawreliak, J A; Orlikowski, D A; Peterson, S C; Satcher, J H; Elsholz, A J; Park, H-S; Remington, B A; Bazin, N; Foster, J M; Graham, P; Park, N; Rosen, P A; Rothman, S R; Higginbotham, A; Suggit, M; Wark, J S

    2013-03-15

    The strength of shock-loaded single crystal tantalum [100] has been experimentally determined using in situ broadband x-ray Laue diffraction to measure the strain state of the compressed crystal, and elastic constants calculated from first principles. The inferred strength reaches 35 GPa at a shock pressure of 181 GPa and is in excellent agreement with a multiscale strength model [N. R. Barton et al., J. Appl. Phys. 109, 073501 (2011)], which employs a hierarchy of simulation methods over a range of length scales to calculate strength from first principles.

  17. Thermal shock testing of low-Z coatings with pulsed hydrogen beams

    International Nuclear Information System (INIS)

    Nakamura, Kazuyuki

    1982-03-01

    Thermal shock testing of candidate low-Z surface coatings for JT-60 application has been made by using a pulsed hydrogen beam apparatus which is operated at a power density of 2KW/cm 2 . The materials tested are PVD (Physical Vapor Deposited) TiC and PVD and CVD (Chemical Vapor Deposited) TiN on molybdenum and Inconel 625. The result shows that CVD TiC on Mo and CVD TiN on Inconel are the most interesting choices for the coating-substrate combinations. (author)

  18. Shock loading of reactor vessel following hypothetical core disruptive accident

    International Nuclear Information System (INIS)

    Srinivas, G.; Doshi, J.B.

    1990-01-01

    Hypothetical Core Disruptive Accident (HCDA) has been historically considered as the maximum credible accident in Fast Breeder Reactor systems. Environmental consequences of such an accident depends to a great extent on the ability of the reactor vessel to maintain integrity during the shock loading following an HCDA. In the present paper, a computational model of the reactor core and the surrounding coolant with a free surface is numerical technique. The equations for conservation of mass, momentum and energy along with an equation of state are considered in two dimensional cylindrical geometry. The reactor core at the end of HCDA is taken as a bubble of hot, vaporized fuel at high temperature and pressure, formed at the center of the reactor vessel and expanding against the surrounding liquid sodium coolant. The free surface of sodium at the top of the vessel and the movement of the core bubble-liquid coolant interface are tracked by Marker and Cell (MAC) procedure. The results are obtained for the transient pressure at the vessel wall and also for the loading on the roof plug by the impact of the slug of liquid sodium. The computer code developed is validated against a benchmark experiment chosen to be ISPRA experiment reported in literature. The computer code is next applied to predict the loading on the Indian Prototype Fast Breeder Reactor (PFBR) being developed at Kalpakkam

  19. A facile way to control phase of tin selenide flakes by chemical vapor deposition

    Science.gov (United States)

    Wang, Zhigang; Pang, Fei

    2018-06-01

    Although two-dimensional (2D) tin selenides are attracting intense attentions, studies on its phase transition are still relatively few. Here we report a facile way to control the phase growth of tin selenide flakes on mica and SiO2/Si by only adjusting nominal Sn:Se ratio, which refers to the amount of loaded SnO2 and Se precursors. High normal Sn:Se ratio induced SnSe flakes, conversely SnSe2 flakes formed. It could be used as a practical guide to selectively synthesize pure phase of single crystalline 2D layered chalcogenide materials similar to tin selenides.

  20. Wear of tin coating and Al-Si alloy substrate against carburized steel under mixed lubrication

    Science.gov (United States)

    Wang, Q.; Cheng, H. S.; Fine, M. E.

    1994-04-01

    Tin coatings on Al-Si alloys are widely used in the automotive industries. The soft tin coating and the harder substrate alloy form a tribological system with the advantages of low friction and reasonably high load-bearing capacity. Wear tests of tin coated Al-Si Z332 alloy in conformal contact against carburized 1016 steel have been carried out under mixed lubrications with SAE 10W30 oil to study the wear mechanisms. Two major wear mechanisms, uniform wear of the tin coating due to micro-plowing and spall pitting related to the substrate are found to contribute to the bearing material loss when the fluid lubrication film is relatively thick (Lambda about 1.6). Under conditions of thinner films (Lambda approximately = 0.8), some local coating debonding occurs. The pitting and local coating debounding are closely related to fracture in the substrate. The bonding between silicon and tin seems to be weaker than between aluminum and tin. During wear, oxidation occurs.

  1. Numerical Simulation of Shock Response and Dynamic Fracture of a Concrete Dam Subjected to Impact Load

    Directory of Open Access Journals (Sweden)

    Lu Lu

    2016-01-01

    Full Text Available The shock response and dynamic fracture of concrete gravity dams under impact load are the key problems to evaluate the antiknock safety of the dam. This study aims at understanding the effects of impact shock on the elastic response and dynamic fracture of concrete gravity dams. Firstly, this paper uses acceleration records of a concrete gravity dam under impact to establish the correct way to determine the concrete gravity dam of the fundamental frequency and present cut sheets multi-degree-of-freedom dynamic modeling. Under strong impact loading, the constitutive relation of concrete gravity dam and the highest frequency of the impact are uncertain. So, the main advantage of this method is avoiding the use of elastic modulus in the calculation. The result indicates that the calculation method is a reliable computational method for concrete gravity dams subjected to impact. Subsequently, the failure process of dam models was numerically simulated based on ABAQUS commercial codes. Finally, this paper puts forward suggestions for future research based on the results of the analysis.

  2. Thermal shock fracture of graphite armor plate under the heat load of plasma disruption

    International Nuclear Information System (INIS)

    Horie, Tomoyoshi; Seki, Masahiro; Ohmori, Junji

    1989-01-01

    Experiments on the thermal shock brittle fracture of graphite plates were performed. Thermal loading which simulated a plasma disruption was produced by an electron beam facility. Pre-cracks produced on the surface propagated to the inside of the specimen even if the thermal stress on the surface was compressive. Two mechanisms are possible to produce tensile stress around the crack tip under thermal shock conditions. Temperature, thermal stress, and the stress intensity factor for the specimen were analyzed based on the finite element method for various heating conditions. The trend of experimental results under the asymmetric heating agrees qualitatively with the analytical results. This phenomenon is important for the design of plasma facing components made of graphite. Establishment of a lifetime prediction procedure including fatigue, fatigue crack growth, and brittle fracture is needed for graphite armors. (orig.)

  3. Nanocrystalline SnO2 formation by oxygen ion implantation in tin thin films

    Science.gov (United States)

    Kondkar, Vidya; Rukade, Deepti; Kanjilal, Dinakar; Bhattacharyya, Varsha

    2018-03-01

    Metallic tin thin films of thickness 100 nm are deposited on fused silica substrates by thermal evaporation technique. These films are implanted with 45 keV oxygen ions at fluences ranging from 5 × 1015 to 5 × 1016 ions cm-2. The energy of the oxygen ions is calculated using SRIM in order to form embedded phases at the film-substrate interface. Post-implantation, films are annealed using a tube furnace for nanocrystalline tin oxide formation. These films are characterized using x-ray diffraction, Raman spectroscopy, UV-vis spectroscopy and photoluminescence spectroscopy. XRD and Raman spectroscopy studies reveal the formation of single rutile phase of SnO2. The size of the nanocrystallites formed decreases with an increase in the ion fluence. The nanocrystalline SnO2 formation is also confirmed by UV-vis and photoluminescence spectroscopy.

  4. 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

  5. Co-selection of antibiotic resistance via copper shock loading on bacteria from a drinking water bio-filter.

    Science.gov (United States)

    Zhang, Menglu; Chen, Lihua; Ye, Chengsong; Yu, Xin

    2018-02-01

    Heavy metal contamination of source water frequently occurred in developing countries as a result of accidents. To address the problems, most of the previous studies have focused on engineering countermeasures. In this study, we investigated the effects of heavy metals, particularly copper, on the development of antibiotic resistance by establishing a copper shock loading test. Results revealed that co-selection occurred rapidly within 6 h. Copper, at the levels of 10 and 100 mg/L, significantly increased bacterial resistance to the antibiotics tested, including rifampin, erythromycin, kanamycin, and a few others. A total of 117 antimicrobial-resistance genes were detected from 12 types of genes, and the relative abundance of most genes (particularly mobile genetic elements intⅠand transposons) was markedly enriched by at least one fold. Furthermore, the copper shock loading altered the bacterial community. Numerous heavy metal and antibiotic resistant strains were screened out and enriched. These strains are expected to enhance the overall level of resistance. More noticeably, the majority of the co-selected antibiotic resistance could sustain for at least 20 h in the absence of copper and antimicrobial drugs. Resistance to vancomycin, erythromycin and lincomycin even could remain for 7 days. The prominent selection pressure by the copper shock loading implies that a real accident most likely poses similar impacts on the water environment. An accidental release of heavy metals would not only cause harm to the ecological environment, but also contribute to the development of bacterial antibiotic resistance. Broader concerns should be raised about the biological risks caused by sudden releases of pollutants by accidents. Copyright © 2017. Published by Elsevier Ltd.

  6. Cren(ulation)-­1,2 Preshot Report

    Energy Technology Data Exchange (ETDEWEB)

    Rousculp, Christopher L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Oro, David Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Griego, Jeffrey Randall [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bradley, Joseph Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hollander, Brian J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reinovsky, Robert Emil [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-12-21

    There is great interest in the behavior of the free surface of tin under shock loading. While it is known that meso-scale surface imperfections can seed the RichtmyerMeshkov Instability (RMI) for a surface that is melted on release, much less is known about a tin surface that is solid, but plastically deforming. Here material properties such as shear and yield strength come into play especially in converging geometry. Previous experiments have been driven by direct contact HE. Usually a thin, flat target coupon is fielded with various single-mode, sinusoidal, machined, profiles on the free surface. The free surface is adjacent to either vacuum or an inert receiver gas. Most of these previous driver/target configurations have been nominal planer geometry. With modern HE it has been straightforward to shock tin into melt on release. However it has been challenging to achieve a low enough pressure for solid state on release. Here we propose to extend the existing base of knowledge to include the behavior of the free surface of tin in cylindrical converging geometry. By shock loading a cylindrical tin shell with a magnetically driven cylindrical liner impactor, the free surface evolution can be diagnosed with proton radiography. With the PHELIX capacitor bank, the drive can easily be varied to span the pressure range to achieve solid, mixed, and liquid states on release.

  7. Criticality conditions of heterogeneous energetic materials under shock loading

    Science.gov (United States)

    Nassar, Anas; Rai, Nirmal Kumar; Sen, Oishik; Udaykumar, H. S.

    2017-06-01

    Shock interaction with the microstructural heterogeneities of energetic materials can lead to the formation of locally heated regions known as hot spots. These hot spots are the potential sites where chemical reaction may be initiated. However, the ability of a hot spot to initiate chemical reaction depends on its size, shape and strength (temperature). Previous study by Tarver et al. has shown that there exists a critical size and temperature for a given shape (spherical, cylindrical, and planar) of the hot spot above which reaction initiation is imminent. Tarver et al. assumed a constant temperature variation in the hot spot. However, the meso-scale simulations show that the temperature distribution within a hot spot formed from processes such as void collapse is seldom constant. Also, the shape of a hot spot can be arbitrary. This work is an attempt towards development of a critical hot spot curve which is a function of loading strength, duration and void morphology. To achieve the aforementioned goal, mesoscale simulations are conducted on porous HMX material. The process is repeated for different loading conditions and void sizes. The hot spots formed in the process are examined for criticality depending on whether they will ignite or not. The metamodel is used to obtain criticality curves and is compared with the critical hot spot curve of Tarver et al.

  8. Fabrication of visible-light-driven Ag/TiO{sub 2} heterojunction composites induced by shock wave

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Chunxiao [School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Chen, Pengwan, E-mail: pwchen@bit.edu.cn [School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081 (China); Liu, Jianjun [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Yin, Hao [Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang 612900, Sichuan Province (China); Gao, Xin; Mei, Xiaofeng [State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081 (China)

    2016-09-15

    Using metatitanic acid (H{sub 2}TiO{sub 3}) and silver nitrate (AgNO{sub 3}) as titanium precursor and silver source respectively, a visible-light responsible Ag/TiO{sub 2} heterojunction photocatalyst is successfully prepared by shock wave with detonation-driven flyer impact. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV–visible diffuse reflectance spectroscopy (UV–Vis DRS) and photoluminescence (PL) emission spectra are employed to characterize the phase structure, morphology, chemical composition and optical property of the recovered samples. The results indicate the metatitanic acid transforms to pure rutile TiO{sub 2} phase by shock wave which possess large surface area. Ag nanoparticles cover on the surface of TiO{sub 2} uniformly and a nanojunction structure is formed efficiently, which play important roles as an electron-conduction bridge and in the surface plasmon resonance effect. Ag modification feasibly improves the separation efficiency for photoinduced electron–hole pairs and enhances the visible-light response. Furthermore, due to the further enhanced separation for photogenerated charges resulting from close interfacial contact of the hetero structure, the obtained Ag/TiO{sub 2} photocatalyst exhibit remarkably improved photocatalytic activities (88% within 2 h) than that of P25 and shock induced pure TiO{sub 2} for the degradation of Rhodamine B under simulated sunlight irradiation. The experimental result shows the shock loading is an effective method to get Ag/TiO{sub 2} photocatalyst and offers new ideas to fabricate other heterojunction composite materials. - Highlights: • Shock wave was a new method of material modification. • The Ag/TiO{sub 2} hetero structure was formed efficiently by shock loading. • The visible-light responsible sample showed an enhanced photocatalytic activity. • This work gave new ideas to fabricate other heterojunction materials.

  9. Studies on Cementation of Tin on Copper and Tin Stripping from Copper Substrate

    Directory of Open Access Journals (Sweden)

    Rudnik E.

    2016-06-01

    Full Text Available Cementation of tin on copper in acid chloride-thiourea solutions leads to the formation of porous layers with a thickness dependent on the immersion time. The process occurs via Sn(II-Cu(I mechanism. Chemical stripping of tin was carried out in alkaline and acid solutions in the presence of oxidizing agents. It resulted in the dissolution of metallic tin, but refractory Cu3Sn phase remained on the copper surface. Electrochemical tin stripping allows complete tin removal from the copper substrate, but porosity and complex phase composition of the tin coating do not allow monitoring the process in unambiguous way.

  10. TIN-X

    DEFF Research Database (Denmark)

    Cannon, Daniel C; Yang, Jeremy J; Mathias, Stephen L

    2017-01-01

    between proteins and diseases, based on text mining data processed from scientific literature. In the current implementation, TIN-X supports exploration of data for G-protein coupled receptors, kinases, ion channels, and nuclear receptors. TIN-X supports browsing and navigating across proteins......Motivation: The increasing amount of peer-reviewed manuscripts requires the development of specific mining tools to facilitate the visual exploration of evidence linking diseases and proteins. Results: We developed TIN-X, the Target Importance and Novelty eXplorer, to visualize the association...

  11. Design and testing of a magnetorheological damper to control both vibration and shock loads for a vehicle crew seat

    Science.gov (United States)

    Becnel, Andrew; Hu, Wei; Hiemenz, Gregory J.; Wereley, Norman M.

    2010-04-01

    A magnetorheological shock absorber (MRSA) prototype is designed, fabricated and tested to integrate semiactive shock and vibration mitigation technology into the existing Expeditionary Fighting Vehicle (EFV) forward seating positions. Utilizing Bingham-Plastic (BP) constitutive fluid relationships and a steady state fluid flow model, the MR valve parameters are determined using magnetic circuit analysis, and subsequently validated via electromagnetic finite element analysis (FEA). Low speed (up to 0.9 m/s) simulations of normal vibration mode operation are conducted on the MRSA prototype using single frequency sinusoidal displacements by a servohydraulic testing machine. The high speed (up to 2.2 m/s) design procedure is verified by using a rail-guided drop test stand to impact a known payload mass onto the damper shaft. A refined hydromechanical model of the MRSA under both cyclic and impact loadings is developed and validated using the measured test data. This ratedependent, mechanisms-based model predicts the time response of the MRSA under both loading conditions. The hydromechanical analysis marks a significant improvement over previous linear models. Key design considerations for the MRSA to accommodate both vibration and shock spectra using a single MR device are presented.

  12. Influence of current density on surface morphology and properties of pulse plated tin films from citrate electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Ashutosh; Bhattacharya, Sumit; Das, Siddhartha; Das, Karabi, E-mail: karabi@metal.iitkgp.ernet.in

    2014-01-30

    Bulk polycrystalline tin films have been processed by pulse electrodeposition technique from a simple solution containing triammonium citrate and stannous chloride. The cathodic investigations have been carried out by galvanostatic methods. As deposited samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). XRD analysis of the deposited films shows microcrystalline grains having β-Sn form. The surface morphology is very rough at lower current density, but becomes smooth at higher current density, and exhibits pyramid type morphology at all the current densities. The effect of current density on microhardness, melting behavior, and electrical resistivity are also reported here.

  13. X-ray line broadening studies on aluminum nitride, titanium carbide and titanium diboride modified by high pressure shock loading

    International Nuclear Information System (INIS)

    Morosin, B.; Graham, R.A.

    1983-01-01

    Powders of AlN, TiC and TiB 2 have been subjected to controlled shock loading with peak pressures in the samples between 14 to 27 GPa and preserved for post-shock study. Broadened x-ray diffraction peak profiles are analyzed by a simplified method and show increases in residual lattice strain and small decreases in crystallite size. Strain values range from 10 -5 to 10 -4 for TiB 2 and to values larger than 10 -3 for TiC and AlN

  14. Dynamic behaviors of a Zr-based bulk metallic glass under ramp wave and shock wave loading

    Directory of Open Access Journals (Sweden)

    Binqiang Luo

    2015-06-01

    Full Text Available Dynamic behaviors of Zr51Ti5Ni10Cu25Al9 bulk metallic glass were investigated using electric gun and magnetically driven isentropic compression device which provide shock and ramp wave loading respectively. Double-wave structure was observed under shock compression while three-wave structure was observed under ramp compression in 0 ∼ 18GPa. The HEL of Zr51Ti5Ni10Cu25Al9 is 8.97 ± 0.61GPa and IEL is 8.8 ± 0.3GPa, respectively. Strength of Zr51Ti5Ni10Cu25Al9 estimated from HEL is 5.0 ± 0.3GPa while the strength estimated from IEL is 3.6 ± 0.1GPa. Shock wave velocity versus particle velocity curve of Zr51Ti5Ni10Cu25Al9 under shock compression appears to be bilinear and a kink appears at about 18GPa. The Lagrangian sound speed versus particle velocity curve of Zr51Ti5Ni10Cu25Al9 under ramp wave compression exhibits two discontinuances and are divided to three regions: elastic, plastic-I and plastic-II. The first jump-down occurs at elastic-plastic transition and the second appears at about 17GPa. In elastic and plastic-I regions, Lagrangian sound speed increases linearly with particle velocity, respectively. Characteristic response of sound speed in plastic-I region disagree with shock result in the same pressure region(7GPa ∼ 18GPa, but is consistent with shock result at higher pressure(18-110GPa.

  15. 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...

  16. High strain rate deformation and fracture of the magnesium alloy Ma2-1 under shock wave loading

    Science.gov (United States)

    Garkushin, G. V.; Kanel', G. I.; Razorenov, S. V.

    2012-05-01

    This paper presents the results of measurements of the dynamic elastic limit and spall strength under shock wave loading of specimens of the magnesium alloy Ma2-1 with a thickness ranging from 0.25 to 10 mm at normal and elevated (to 550°C) temperatures. From the results of measurements of the decay of the elastic precursor of a shock compression wave, it has been found that the plastic strain rate behind the front of the elastic precursor decreases from 2 × 105 s-1 at a distance of 0.25 mm to 103 s-1 at a distance of 10 mm. The plastic strain rate in a shock wave is one order of magnitude higher than that in the elastic precursor at the same value of the shear stress. The spall strength of the alloy decreases as the solidus temperature is approached.

  17. On the electrochemistry of tin oxide coated tin electrodes in lithium-ion batteries

    International Nuclear Information System (INIS)

    Böhme, Solveig; Edström, Kristina; Nyholm, Leif

    2015-01-01

    As tin based electrodes are of significant interest in the development of improved lithium-ion batteries it is important to understand the associated electrochemical reactions. In this work it is shown that the electrochemical behavior of SnO_2 coated tin electrodes can be described based on the SnO_2 and SnO conversion reactions, the lithium tin alloy formation and the oxidation of tin generating SnF_2. The CV, XPS and SEM data, obtained for electrodeposited tin crystals on gold substrates, demonstrates that the capacity loss often observed for SnO_2 is caused by the reformed SnO_2 layer serving as a passivating layer protecting the remaining tin. Capacities corresponding up to about 80 % of the initial SnO_2 capacity could, however, be obtained by cycling to 3.5 V vs. Li"+/Li. It is also shown that the oxidation of the lithium tin alloy is hindered by the rate of the diffusion of lithium through a layer of tin with increasing thickness and that the irreversible oxidation of tin to SnF_2 at potentials larger than 2.8 V vs. Li"+/Li is due to the fact that SnF_2 is formed below the SnO_2 layer. This improved electrochemical understanding of the SnO_2/Sn system should be valuable in the development of tin based electrodes for lithium-ion batteries.

  18. Influence of sweeping detonation-wave loading on damage evolution during spallation loading of tantalum in both a planar and curved geometry

    Energy Technology Data Exchange (ETDEWEB)

    Gray, George Thompson III [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hull, Lawrence Mark [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Livescu, Veronica [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Faulkner, James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Briggs, Matthew E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Meyer, Ross Keith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Andrews, Heather Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hare, Steven John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jakulewicz, Micah Shawn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Shinas, Michael A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-30

    Widespread research over the past five decades has provided a wealth of experimental data and insight concerning the shock hardening, damage evolution, and the spallation response of materials subjected to square-topped shock-wave loading profiles. However, fewer quantitative studies have been conducted on the effect of direct, in-contact, high explosive (HE)-driven Taylor wave (unsupported shocks) loading on the shock hardening, damage evolution, or spallation response of materials. Systematic studies quantifying the effect of sweeping-detonation wave loading are yet sparser. In this study, the damage evolution and spallation response of Ta is shown to be critically dependent on the peak shock stress, the geometry of the sample (flat or curved plate geometry), and the shock obliquity during sweeping-detonation-wave shock loading. Sweepingwave loading in the flat-plate geometry is observed to: a) yield a lower spall strength than previously documented for 1-D supported-shock-wave loading, b) exhibit increased shock hardening as a function of increasing obliquity, and c) lead to an increased incidence of deformation twin formation with increasing shock obliquity. Sweeping-wave loading of a 10 cm radius curved Ta plate is observed to: a) lead to an increase in the shear stress as a function of increasing obliquity, b) display a more developed level of damage evolution, extensive voids and coalescence, and lower spall strength with obliquity in the curved plate than seen in the flat-plate sweeping-detonation wave loading for an equivalent HE loading, and c) no increased propensity for deformation twin formation with increasing obliquity as seen in the flat-plate geometry. The overall observations comparing and contrasting the flat versus curved sweeping-wave spall experiments with 1D loaded spallation behavior suggests a coupled influence of obliquity and geometry on dynamic shock-induced damage evolution and spall strength. Coupled experimental and modeling research

  19. Low-temperature Synthesis of Tin(II) Oxide From Tin(II) ketoacidoximate Precursor

    KAUST Repository

    Alshankiti, Buthainah

    2015-04-01

    Sn (II) oxide finds numerous applications in different fields such as thin film transistors1, solar cells2 and sensors.3 In this study we present the fabrication of tin monoxide SnO by using Sn (II) ketoacid oximate complexes as precursors. Tin (II) ketoacidoximates of the type [HON=CRCOO]2Sn where R= Me 1, R= CH2Ph 2, and [(MeON=CMeCOO)3Sn]- NH4 +.2H2O 3 were synthesized by in situ formation of the ketoacid oximate ligand. The crystal structures were determined via single crystal X- ray diffraction of the complexes 1-3 revealed square planar and square pyramidal coordination environments for the Sn atom. Intramolecular hydrogen bonding is observed in all the complexes. Furthermore, the complexes were characterized by Infrared (IR), Nuclear Magnetic Resonance (NMR) and elemental analysis. From thermogravimetric analysis of 1-3, it was found that the complexes decomposed in the range of 160 – 165 oC. Analysis of the gases evolved during decomposition indicated complete loss of the oximato ligand in one step and the formation of SnO. Spin coating of 1 on silicon or glass substrate show uniform coating of SnO. Band gaps of SnO films were measured and found to be in the range of 3.0 – 3.3 eV by UV-Vis spectroscopy. X-ray photoelectron spectroscopy indicated surface oxidation of the SnO film. Heating 1 above 140 oC in air gives SnO of size ranging from 10 – 500 nm and is spherical in shape. The SnO nanomaterial is characterized by powder X-ray diffraction(XRD), Raman spectroscopy, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM).

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. In-situ laser processing and microstructural characteristics of YBa2Cu3O7-δ thin films on Si with TiN buffer layer

    International Nuclear Information System (INIS)

    Tiwari, P.; Zheleva, T.; Narayan, J.

    1993-01-01

    The authors have prepared high-quality superconducting YBa 2 Cu 3 O 7 -δ (YBCO) thin films on Si(100) with TiN as a buffer layer using in-situ multitarget deposition system. Both TiN and YBCO thin films were deposited sequentially by KrF excimer laser ( | = 248 nm ) at substrate temperature of 650 C . Thin films were characterized using X-ray diffraction (XRD), four-point-probe ac resistivity, scanning electron microscopy (S E M), transmission electron microscopy (TEM), and Rutherford backscattering (RBS). The TiN buffer layer was epitaxial and the epitaxial relationship was found to be cube on cube with TiN parallel Si. YBCO thin films on Si with TiN buffer layer showed the transition temperature of 90-92K with T co (zero resistance temperature) of 84K. The authors have found that the quality of the buffer layer is very important in determining the superconducting transition temperature of the thin film. The effects of processing parameters and the correlation of microstructural features with superconducting properties are discussed in detail

  5. Discrete Element Simulation of Elastoplastic Shock Wave Propagation in Spherical Particles

    Directory of Open Access Journals (Sweden)

    M. Shoaib

    2011-01-01

    Full Text Available Elastoplastic shock wave propagation in a one-dimensional assembly of spherical metal particles is presented by extending well-established quasistatic compaction models. The compaction process is modeled by a discrete element method while using elastic and plastic loading, elastic unloading, and adhesion at contacts with typical dynamic loading parameters. Of particular interest is to study the development of the elastoplastic shock wave, its propagation, and reflection during entire loading process. Simulation results yield information on contact behavior, velocity, and deformation of particles during dynamic loading. Effects of shock wave propagation on loading parameters are also discussed. The elastoplastic shock propagation in granular material has many practical applications including the high-velocity compaction of particulate material.

  6. Synthesis and Characterization of Nanocomposites Tin Oxide-Graphene Doping Pd Using Polyol Method

    Directory of Open Access Journals (Sweden)

    Aminuddin Debataraja

    2018-05-01

    Full Text Available This paper report on polyol method for Pd doped tin oxide-graphene nanocomposite thin film. XRD result shows sharp peaks at certain 2θ value and match with tin oxide, graphene, and Pd database. FTIR result shows peak from alcohol chain for –OH strong bonded absorption (3444 cm-1, also there are aldehyde and ketone which are indicated by C=O strong absorption (1751 cm-1. Moreover, alkene is also formed for decreasing symmetry intensity C=C (1616 cm-1, while alkyne is formed at strong deformation absorption at 646 and 613 cm-1. SEM and TEM result show SnO2 particles are attached uniformly on graphene surface layer. The composition for C, O, Sn, and Pd are 33.13, 25.58, 35.35 and 5.94%, respectively. This result indicated that the good composition is formed for Pd doped SnO2-graphene nanocomposite. The nanocomposite is promising materials for toxic gas sensor application at low temperature.

  7. Empirical Model Development for Predicting Shock Response on Composite Materials Subjected to Pyroshock Loading

    Science.gov (United States)

    Gentz, Steven J.; Ordway, David O; Parsons, David S.; Garrison, Craig M.; Rodgers, C. Steven; Collins, Brian W.

    2015-01-01

    The NASA Engineering and Safety Center (NESC) received a request to develop an analysis model based on both frequency response and wave propagation analyses for predicting shock response spectrum (SRS) on composite materials subjected to pyroshock loading. The model would account for near-field environment (approx. 9 inches from the source) dominated by direct wave propagation, mid-field environment (approx. 2 feet from the source) characterized by wave propagation and structural resonances, and far-field environment dominated by lower frequency bending waves in the structure. This report documents the outcome of the assessment.

  8. In vitro assessments on bacterial adhesion and corrosion performance of TiN coating on Ti6Al4V titanium alloy synthesized by multi-arc ion plating

    International Nuclear Information System (INIS)

    Lin Naiming; Huang Xiaobo; Zhang Xiangyu; Fan Ailan; Qin Lin; Tang Bin

    2012-01-01

    TiN coating was synthesized on Ti6Al4V titanium alloy surface by multi-arc ion plating (MIP) technique. Surface morphology, cross sectional microstructure, elemental distributions and phase compositions of the obtained coating were analyzed by means of scanning electron microscope (SEM), optical microscope (OM), glow discharge optical emission spectroscope (GDOES) and X-ray diffraction (XRD). Bacterial adhesion and corrosion performance of Ti6Al4V and the TiN coating were assessed via in vitro bacterial adhesion tests and corrosion experiments, respectively. The results indicated that continuous and compact coating which was built up by pure TiN with a typical columnar crystal structure has reached a thickness of 1.5 μm. This TiN coating could significantly reduce the bacterial adhesion and enhance the corrosion resistance of Ti6Al4V substrate.

  9. Comparative assessment of gastrointestinal irritant potency in man of tin(II) chloride and tin migrated from packaging.

    Science.gov (United States)

    Boogaard, Peter J; Boisset, Michel; Blunden, Steve; Davies, Scot; Ong, Teng Jin; Taverne, Jean-Pierre

    2003-12-01

    Tin is present in low concentrations in most canned foods and beverages, the highest levels being found in products packaged in unlacquered or partially lacquered tinplate cans. A limited number of case-reports of acute gastrointestinal disorders after consumption of food containing 100-500 mg/kg tin have been reported, but these reports suffer many insufficiencies. Controlled clinical studies on acute effects of tin migrated from packaging suggest a threshold concentration for adverse effects (AEs) of >730 mg/kg. Two separate randomised, single-centre, double-blind, crossover studies, enabling comparison of the tolerability of tin added as tin(II) chloride at concentrations of soup in 24 volunteers (Study 2) were carried out. Distribution studies were conducted to get insight in the acute AEs of low molecular weight (clear dose-response relationship was only observed when tin was added as tin(II) chloride in tomato juice. No clinically significant AEs were reported in Study 2 and comparison of the incidence of tin-related AEs showed no difference between the dose levels (including control). Tin species of low molecular weight in supernatant represented 31-32% of total tin in canned tomato soup versus 56-61% in juice freshly spiked with tin(II) chloride. Differences in the incidence of AEs following administration of tomato juice with 161 and 264 mg of tin per kg and tomato soup with 201 and 267 mg of tin per kg likely results from differences in the concentration of low molecular weight tin species and in the nature of tin complexes formed. The results of this work demonstrate that tin levels up to 267 mg/kg in canned food cause no AEs in healthy adults and support the currently proposed tin levels of 200 mg/kg and 250 mg/kg for canned beverages and canned foods, respectively, as safe levels for adults in the general population.

  10. Work Function Tuning in Sub-20nm Titanium Nitride (TiN) Metal Gate: Mechanism and Engineering

    KAUST Repository

    Hasan, Mehdi

    2011-07-01

    Scaling of transistors (the building blocks of modern information age) provides faster computation at the expense of excessive power dissipation. Thus to address these challenges, high-k/metal gate stack has been introduced in commercially available microprocessors from 2007. Since then titanium nitride (TiN) metal gate’s work function (Wf) tunability with its thickness (thickness increases, work function increases) is a well known phenomenon. Many hypotheses have been made over the years which include but not limited to: trap charge and metal gate nucleation, nitrogen concentration, microstructure agglomeration and global stress, metal oxide formation, and interfacial oxide thickness. However, clear contradictions exist in these assumptions. Also, nearly all these reports skipped a comprehensive approach to explain this complex paradigm. Therefore, in this work we first show a comprehensive physical investigation using transmission electron microcopy/electron energy loss spectroscopy (TEM/EELS), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) to show replacement of oxygen by nitrogen in the metal/dielectric interface, formation of TiONx, reduction of Ti/N concentration and grain size increment happen with TiN thickness increment and thus may increase the work function. Then, using these finding, we experimentally show 100meV of work function modulation in 10nm TiN Metal-oxide-semiconductor capacitor by using low temperature oxygen annealing. A low thermal budget flow (replicating gate-last) shows similar work function boost up. Also, a work function modulation of 250meV has been possible using oxygen annealing and applying no thermal budget. On the other hand, etch-back of TiN layer can decrease the work function. Thus this study quantifies role of various factors in TiN work function tuning; it also reproduces the thickness varied TiN work function modulation in single thickness TiN thus reducing the

  11. Hydrolysis of bis(dimethylamido)tin to tin (II) oxyhydroxide and its selective transformation into tin (II) or tin (IV) oxide

    KAUST Repository

    Khanderi, Jayaprakash

    2015-03-01

    Sn6O4(OH)4, a hydrolysis product of Sn(NMe2)2, is transformed to tin (II) or tin (IV) oxide by solid and solution phase processing. Tin (II) oxide is formed by heating Sn6O4(OH)4 at ≤200 °C in air or under inert atmosphere. Tin (IV) oxide nanoparticles are formed in the presence of a carboxylic acid and base in air at room temperature. IR spectroscopy, Raman spectroscopy, thermogravimetry (coupled with infrared spectroscopy), powder X-ray diffraction, high temperature X-ray diffraction, scanning electron and transmission electron microscopy are used for the characterization of Sn6O4(OH)4 and the investigation of its selective decomposition into SnO or SnO2. Spectroscopic and X-ray diffraction results indicate that SnO is formed by the removal of water from crystalline Sn6O4(OH)4. SEM shows octahedral morphology of the Sn6O4(OH)4, SnO and SnO2 with particle size from 400 nm-2 μm during solid state conversion. Solution phase transformation of Sn6O4(OH)4 to SnO2 occurs in the presence of potassium glutarate and oxygen. SnO2 particles are 15-20 nm in size.

  12. Relative Shock Effects in Mixed Powders of Calcite, Gypsum, and Quartz: A Calibration Scheme from Shock Experiments

    Science.gov (United States)

    Bell, Mary S.

    2009-01-01

    The shock behavior of calcite and gypsum is important in understanding the Cretaceous/Tertiary event and other terrestrial impacts that contain evaporite sediments in their targets. Most interest focuses on issues of devolatilization to quantify the production of CO2 or SO2 to better understand their role in generating a temporary atmosphere and its effects on climate and biota [e.g., papers in 1,2,3,4]. Devolatilization of carbonate is also important because the dispersion and fragmentation of ejecta is strongly controlled by the expansion of large volumes of gas during the impact process as well [5,6]. Shock recovery experiments for calcite yield seemingly conflicting results: early experimental devolatilization studies [7,8,9] suggested that calcite was substantially outgassed at 30 GPa (> 50%). However, the recent petrographic work of [10,11,12] presented evidence that essentially intact calcite is recovered from 60 GPa experiments. [13] reported results of shock experiments on anhydrite, gypsum, and mixtures of those phases with silica. Their observations indicate 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 (preliminary) report of shock experiments on calcite, anhydrite, and gypsum, [14] observe calcite recrystallization when shock loaded at 61 GPa, only intensive plastic deformation in anhydrite shock loaded at 63 GPa, and gypsum converted to anhydrite when shock loaded at 56 GPa. [15] shock loaded anhydrite and quartz to a peak pressure of 60 GPa. All of the quartz grains were trans-formed to glass and 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 suggest that recrystallization of anhydrite grains is the result of a solid state transformation. [16] reanalyzed the calcite and anhydrite shock

  13. The Effect of Ankle, Knee and Hip Isokinetic Fatigue on Shock Absorption and Rate of Loading during Pair-leg Landing

    Directory of Open Access Journals (Sweden)

    Hamideh Khodaveisi

    2016-12-01

    Conclusion: Findings of this study indicate that the fatigue protocol using Isokinetic devices with uniform speed, increases muscle strength due to generating stress at all the joints, thereby, compensating the active and passive joints for shock absorption, and load distribution on the lower extremities. 

  14. Growth Structural and Optical Properties of the Thermally Evaporated Tin Diselenide (SnSe2) Thin Films

    OpenAIRE

    R. Sachdeva1,; M. Sharma1,; A. Devi1,; U. Parihar1,; N. Kumar1,; N. Padha1,; C.J. Panchal

    2011-01-01

    Tin diselenide (SnSe2) compound was prepared by melt-quenching technique from its constituent elements. The phase structure and composition of the chemical constituents present in the bulk has been determined using X-ray diffraction (XRD) and energy dispersion X-ray analysis (EDAX) respectively. SnSe2 thin films were grown using direct thermal evaporation of SnSe2 compound material on chemically cleaned glass substrate, which were held at different substrate temperatures. X-ray diffraction an...

  15. 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

  16. Shock diffraction in alumina powder

    International Nuclear Information System (INIS)

    Venz, G.; Killen, P.D.; Page, N.W.

    1996-01-01

    In order to produce complex shaped components by dynamic compaction of ceramic powders detailed knowledge of their response under shock loading conditions is required. This work attempts to provide data on release effects and shock attenuation in 1 μm and 5 μm α-alumina powders which were compacted to between 85 % and 95 % of the solid phase density by the impact of high velocity steel projectiles. As in previous work, the powder was loaded into large cylindrical dies with horizontal marker layers of a contrasting coloured powder to provide a record of powder displacement in the recovered specimens. After recovery and infiltration with a thermosetting resin the specimens were sectioned and polished to reveal the structure formed by the passage of the projectile and shock wave. Results indicate that the shock pressures generated were of the order of 0.5 to 1.4 GPa and higher, with shock velocities and sound speeds in the ranges 650 to 800 m/s and 350 to 400 m/s respectively

  17. Gas Sensing Properties of Indium Tin Oxide Nanofibers

    Directory of Open Access Journals (Sweden)

    Shiyou Xu

    2009-11-01

    Full Text Available Indium Tin Oxide (ITO nanofibers were fabricated by the electrospinning process. The morphology and crystal structure of ITO nanofibers were studied by SEM, XRD, and TEM respectively. The results showed that polycrystalline ITO nanofibers with an average diameter of 80 nm were obtained. Sensors based on these nanofibers were fabricated by collecting these nanofibers on the integrated sensor platforms. The ITO nanofiber-based sensors showed very fast and high sensor responses at both room and elevated temperatures for NO2. The ratios of resistance in NO2 over that in air were 5 at room temperature and 34 at the optimal working temperature, respectively. The ITO nanofiber-based sensor can be repeatedly used. The details for the fast, enhanced sensor responses and the optimal temperature were discussed.

  18. XRF measurements of tin, copper and zinc in antifouling paints coated on leisure boats

    International Nuclear Information System (INIS)

    Ytreberg, Erik; Bighiu, Maria Alexandra; Lundgren, Lennart; Eklund, Britta

    2016-01-01

    Tributyltin (TBT) and other organotin compounds have been restricted for use on leisure boats since 1989 in the EU. Nonetheless, release of TBT is observed from leisure boats during hull maintenance work, such as pressure hosing. In this work, we used a handheld X-ray Fluorescence analyser (XRF) calibrated for antifouling paint matrixes to measure tin, copper and zinc in antifouling paints coated on leisure boats in Sweden. Our results show that over 10% of the leisure boats (n = 686) contain >400 μg/cm 2 of tin in their antifouling coatings. For comparison, one layer (40 μm dry film) of a TBT-paint equals ≈ 800 μg Sn/cm 2 . To our knowledge, tin has never been used in other forms than organotin (OT) in antifouling paints. Thus, even though the XRF analysis does not provide any information on the speciation of tin, the high concentrations indicate that these leisure boats still have OT coatings present on their hull. On several leisure boats we performed additional XRF measurements by progressively scraping off the top coatings and analysing each underlying layer. The XRF data show that when tin is detected, it is most likely present in coatings close to the hull with several layers of other coatings on top. Thus, leaching of OT compounds from the hull into the water is presumed to be negligible. The risk for environmental impacts arises during maintenance work such as scraping, blasting and high pressure hosing activities. The data also show that many boat owners apply excessive paint layers when following paint manufacturers recommendations. Moreover, high loads of copper were detected even on boats sailing in freshwater, despite the more than 20 year old ban, which poses an environmental risk that has not been addressed until now. - Highlights: • A new XRF application for analysing metals in antifouling paints has been used. • Almost 700 leisure boats were analysed for tin, copper and zinc. • Over 10% of the leisure boats contained high, >400

  19. Phase transition in a shock loaded 304 stainless steel

    International Nuclear Information System (INIS)

    Naulin, G.

    1989-11-01

    Systematic shock recovery experiments have been performed on a Z2 CN 18-10 stainless steel (304 AISI), shocked in a pressure range of 5-13 GPa. The pulse durations lay between 0.1 μs and 2 μs. The phases transformation γ (fcc) to α' (bcc) is studied. The evolution of microstructures, the nucleation and the coalescence of α' phase embryos have been observed by TEM examinations. Quantitative measurements of the α' phase allow to plot diagrams of transformed phase versus shock pressure and pulse duration. Manganin gages allow to know the pressure evolution during the impact. The Olson and Cohen model describes the development of the α' phase versus the plastic deformation. An adaptation of this model has been developed, which describes the development of the α' phase versus shock pressure and pulse duration. Theoretical laws give a good correlation with experimental results [fr

  20. Shock loading characteristics of Zr and Ti metals using dual beam velocimeter

    Energy Technology Data Exchange (ETDEWEB)

    Saxena, A. K., E-mail: a-saxena@barc.gov.in; Kaushik, T. C.; Gupta, Satish C. [Applied Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2015-08-21

    The characteristics of titanium and zirconium metal foils under shock loading have been studied up to 16 GPa and 12 GPa pressure, respectively, using portable electric gun setup as projectile launcher. In these experiments, the capabilities of a single Fabry-Perot velocimeter have been enhanced by implementing it in dual beam mode to record the two velocity profiles on a single streak camera. The measured equation of state data for both the metals have been found to be well in agreement with the reported Hugoniot, within experimental accuracies. A phase transition from α to ω phase has been detected near to 11.4 GPa for titanium and 8.2 GPa for zirconium in the rising part of target-glass interface velocity profile.

  1. Effect of various additives on morphological and structural characteristics of pulse electrodeposited tin coatings from stannous sulfate electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Ashutosh, E-mail: stannum.ashu@gmail.com [Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur 721302 (India); Das, Karabi [Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur 721302 (India); Fecht, Hans-J. [Institut für Mikro- und Nanomaterialien, Universität Ulm, D-89081 Ulm (Germany); Das, Siddhartha [Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur 721302 (India)

    2014-09-30

    Graphical abstract: - Highlights: • PEG and thiourea act as grain refiners, and Triton X-100 acts as brightener in bath. • Additives refine the crystallite size and modify the orientation of lattice planes. • Dendritic and nodular growths are reduced when additives are used in combination. - Abstract: The pulse electrodeposited tin coatings are synthesized from an acidic electrolyte (stannous sulfate, SnSO{sub 4}30 g/L and sulfuric acid, H{sub 2}SO{sub 4}—200 g/L) containing various additives (polyethylene glycol (PEG), thiourea and Triton X-100). The effect of the additives on surface morphology, preferred orientation of grains, grain size, and surface roughness has been studied. The final coatings are characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and surface profilometry. In the absence of additives, tin deposition is associated with prominent hydrogen evolution reaction giving rise to rough deposits. Both PEG and thiourea act as grain refiner while Triton X-100 acts as a brightener in the electrolyte. The cathodic polarization on the reduction of the tin (II) ions is more pronounced when a combination of additives is used and further, fine-grained, smooth and shiny electrodeposits of tin are obtained due to a synergistic effect of the adsorbed species.

  2. One pot synthesis of multi-functional tin oxide nanostructures for high efficiency dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Wali, Qamar; Fakharuddin, Azhar; Yasin, Amina; Ab Rahim, Mohd Hasbi; Ismail, Jamil; Jose, Rajan, E-mail: rjose@ump.edu.my

    2015-10-15

    Photoanode plays a key role in dye sensitized solar cells (DSSCs) as a scaffold for dye molecules, transport medium for photogenerated electrons, and scatters light for improved absorption. Herein, tin oxide nanostructures unifying the above three characteristics were optimized by a hydrothermal process and used as photoanode in DSSCs. The optimized morphology is a combination of hollow porous nanoparticles of size ∼50 nm and micron sized spheres with BET surface area (up to 29 m{sup 2}/g) to allow large dye-loading and light scattering as well as high crystallinity to support efficient charge transport. The optimized morphology gave the highest photovoltaic conversion efficiency (∼7.5%), so far achieved in DSSCs with high open circuit voltage (∼700 mV) and short circuit current density (∼21 mA/cm{sup 2}) employing conventional N3 dye and iodide/triiodide electrolyte. The best performing device achieved an incident photon to current conversion efficiency of ∼90%. The performance of the optimized tin oxide nanostructures was comparable to that of conventional titanium based DSSCs fabricated at similar conditions. - Graphical abstract: Tin oxide hollow nanostructure simultaneously supporting improved light scattering, dye-loading, and charge transport yielded high photovoltaic conversion efficiency in dye-sensitized solar cells. - Highlights: • Uniformly and bimodelly distributed tin oxide hollow nanospheres (HNS) are synthesized. • Uniform HNS are of size ∼10 nm; bimodel HNS has additional size up to ∼800 nm. • They are evaluated as photoelectrodes in dye-sensitized solar cells (DSSCs). • The uniform HNS increase dye-loading and the larger increase light scattering in DSSCs. • Photo conversion efficiency ∼7.5% is achieved using bimodel HNS.

  3. Inorganic ion exchanger based on tin/titanium mixed oxide doped with europium to be used in radioactive waste

    International Nuclear Information System (INIS)

    Paganini, Paula P.; Felinto, Maria Claudia F.C.; Kodaira, Claudia A.; Brito, Hermi F.

    2009-01-01

    This work presents the results of synthesis and characterization of an inorganic ion exchanger based on tin/titanium mixed oxides doped with europium (SnO 2 /TiO 2 :Eu 3+ ) to be used in environmental field. The adsorption study of nickel was realized in this exchanger to recover the nickel metal which is in thorium-nickel alloys used as electrode of discharge lamps. The studied exchanger was synthesized by neutralization of tin chloride (IV) and titanium chloride (III) mixed solution and characterized by thermogravimetric measurement (TG), Differential Scanning Calorimetry (DSC), X-Ray Powder Diffraction (XRD), Infrared Spectroscopy (IR) and Scanning Electron Microscopy (SEM). The adsorption study showed that these inorganic ion exchangers are good materials to recovery nickel with high weight distribution ratios (Dw Ni 2+ ) and percent adsorption. (author)

  4. International strategic minerals inventory summary report; tin

    Science.gov (United States)

    Sutphin, D.M.; Sabin, A.E.; Reed, B.L.

    1990-01-01

    The International Strategic Minerals Inventory tin inventory contains records for 56 major tin deposits and districts in 21 countries. These countries accounted for 98 percent of the 10 million metric tons of tin produced in the period 1934-87. Tin is a good alloying metal and is generally nontoxic, and its chief uses are as tinplate for tin cans and as solder in electronics. The 56 locations consist of 39 lode deposits and 17 placers and contain almost 7.5 million metric tons of tin in identified economic resources (R1E) and another 1.5 million metric tons of tin in other resource categories. Most of these resources are in major deposits that have been known for over a hundred years. Lode deposits account for 44 percent of the R1E and 87 percent of the resources in other categories. Placer deposits make up the remainder. Low-income and middle-income countries, including Bolivia and Brazil and countries along the Southeast Asian Tin Belt such as Malaysia, Thailand, and Indonesia account for 91 percent of the R1E resources of tin and for 61 percent of resources in other categories. The United States has less than 0.05 percent of the world's tin R1E in major deposits. Available data suggest that the Soviet Union may have about 4 percent of resources in this category. The industrial market economy countries of the United States, Japan, Federal Republic of Germany, and the United Kingdom are major consumers of tin, whereas the major tin-producing countries generally consume little tin. The Soviet Union and China are both major producers and consumers of tin. At the end of World War II, the four largest tin-producing countries (Bolivia, the Belgian Congo (Zaire), Nigeria, and Malaysia) produced over 80 percent of the world's tin. In 1986, the portion of production from the four largest producers (Malaysia, Brazil, Soviet Union, Indonesia) declined to about 55 percent, while the price of tin rose from about $1,500 to $18,000 per metric ton. In response to tin shortages

  5. Transient Three-Dimensional Analysis of Side Load in Liquid Rocket Engine Nozzles

    Science.gov (United States)

    Wang, Ten-See

    2004-01-01

    Three-dimensional numerical investigations on the nozzle start-up side load physics were performed. The objective of this study is to identify the three-dimensional side load physics and to compute the associated aerodynamic side load using an anchored computational methodology. The computational methodology is based on an unstructured-grid, and pressure-based computational fluid dynamics formulation, and a simulated inlet condition based on a system calculation. Finite-rate chemistry was used throughout the study so that combustion effect is always included, and the effect of wall cooling on side load physics is studied. The side load physics captured include the afterburning wave, transition from free- shock to restricted-shock separation, and lip Lambda shock oscillation. With the adiabatic nozzle, free-shock separation reappears after the transition from free-shock separation to restricted-shock separation, and the subsequent flow pattern of the simultaneous free-shock and restricted-shock separations creates a very asymmetric Mach disk flow. With the cooled nozzle, the more symmetric restricted-shock separation persisted throughout the start-up transient after the transition, leading to an overall lower side load than that of the adiabatic nozzle. The tepee structures corresponding to the maximum side load were addressed.

  6. Hydrodynamic simulations of microjetting from shock-loaded grooves

    Science.gov (United States)

    Roland, C.; de Rességuier, T.; Sollier, A.; Lescoute, E.; Soulard, L.; Loison, D.

    2017-01-01

    The interaction of a shock wave with a free surface which has geometrical defects, such as cavities or grooves, may lead to the ejection of micrometric debris at velocities of km/s. This process can be involved in many applications, like pyrotechnics or industrial safety. Recent laser shock experiments reported elsewhere in this conference have provided some insight into jet formation as well as jet tip velocities for various groove angles and shock pressures. Here, we present hydrodynamic simulations of these experiments, in both 2D and 3D geometries, using both finite element method and smoothed particle hydrodynamics. Numerical results are compared to several theoretical predictions including the Richtmyer-Meshkov instabilities. The role of the elastic-plastic behavior on jet formation is illustrated. Finally, the possibility to simulate the late stage of jet expansion and fragmentation is explored, to evaluate the mass distribution of the ejecta and their ballistic properties, still essentially unknown in the experiments.

  7. Acetylene Gas-Sensing Properties of Layer-by-Layer Self-Assembled Ag-Decorated Tin Dioxide/Graphene Nanocomposite Film

    OpenAIRE

    Jiang, Chuanxing; Zhang, Dongzhi; Yin, Nailiang; Yao, Yao; Shaymurat, Talgar; Zhou, Xiaoyan

    2017-01-01

    This paper demonstrates an acetylene gas sensor based on an Ag-decorated tin dioxide/reduced graphene oxide (Ag–SnO2/rGO) nanocomposite film, prepared by layer-by-layer (LbL) self-assembly technology. The as-prepared Ag–SnO2/rGO nanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectrum. The acetylene sensing properties were investigated using different working temperatures and gas concentrations. A...

  8. Investigation of thermal and hot-wire chemical vapor deposition copper thin films on TiN substrates using CupraSelect as precursor.

    Science.gov (United States)

    Papadimitropoulos, G; Davazoglou, D

    2011-09-01

    Copper films were deposited on oxidized Si substrates covered with TiN using a novel chemical vapor deposition reactor in which reactions were assisted by a heated tungsten filament (hot-wire CVD, HWCVD). Liquid at room temperature hexafluoroacetylacetonate Cu(I) trimethylvinylsilane (CupraSelect) was directly injected into the reactor with the aid of a direct-liquid injection (DLI) system using N2 as carrier gas. The deposition rates of HWCVD Cu films obtained on TiN covered substrates were found to increase with filament temperature (65 and 170 degrees C were tested). The resistivities of HWCVD Cu films were found to be higher than for thermally grown films due to the possible presence of impurities into the Cu films from the incomplete dissociation of the precursor and W impurities caused by the presence of the filament. For HWCVD films grown at a filament temperature of 170 degrees C, smaller grains are formed than at 65 degrees C as shown from the taken SEM micrographs. XRD diffractograms taken on Cu films deposited on TiN could not reveal the presence of W compounds originating from the filament because the relative peak was masked by the TiN [112] peak.

  9. Mechanical vibration and shock analysis, sinusoidal vibration

    CERN Document Server

    Lalanne, Christian

    2014-01-01

    Everything engineers need to know about mechanical vibration and shock...in one authoritative reference work! This fully updated and revised 3rd edition addresses the entire field of mechanical vibration and shock as one of the most important types of load and stress applied to structures, machines and components in the real world. Examples include everything from the regular and predictable loads applied to turbines, motors or helicopters by the spinning of their constituent parts to the ability of buildings to withstand damage from wind loads or explosions, and the need for cars to m

  10. Corrosion behavior of TiN, TiAlN, TiAlSiN thin films deposited on tool steel in the 3.5 wt.% NaCl solution

    International Nuclear Information System (INIS)

    Yoo, Yun Ha; Le, Diem Phuong; Kim, Jung Gu; Kim, Sun Kyu; Vinh, Pham Van

    2008-01-01

    TiN, TiAlN and TiAlSiN hard coatings were deposited onto AISI H13 tool steel by cathodic arc plasma method. X-ray diffraction (XRD) analysis confirmed that incorporation of Al and Si into TiN led to refinement of microstructure. From the results of potentiodynamic polarization test and electrochemical impedance spectroscopy (EIS) test conducted in an aerated 3.5% NaCl solution, the TiAlSiN film showed the best corrosion resistance with the lowest corrosion current density and porosity, the highest protective efficiency and total resistance (pore resistance plus charge transfer resistance)

  11. Shock compression of geological materials

    International Nuclear Information System (INIS)

    Kirk, S; Braithwaite, C; Williamson, D; Jardine, A

    2014-01-01

    Understanding the shock compression of geological materials is important for many applications, and is particularly important to the mining industry. During blast mining the response to shock loading determines the wave propagation speed and resulting fragmentation of the rock. The present work has studied the Hugoniot of two geological materials; Lake Quarry Granite and Gosford Sandstone. For samples of these materials, the composition was characterised in detail. The Hugoniot of Lake Quarry Granite was predicted from this information as the material is fully dense and was found to be in good agreement with the measured Hugoniot. Gosford Sandstone is porous and undergoes compaction during shock loading. Such behaviour is similar to other granular material and we show how it can be described using a P-a compaction model.

  12. Effective Shear Viscosity of Iron under Shock-Loading Condition

    International Nuclear Information System (INIS)

    Ma Xiao-Juan; Liu Fu-Sheng; Sun Yan-Yun; Zhang Ming-Jian; Peng Xiao-Juan; Li Yong-Hong

    2011-01-01

    We combine the flyer-impact experiment and improve the finite difference method to solve whether the shear viscosity coefficient of shock iron is more reliable. We find that the numerical simulated profile agrees well with the measured one, from which the determined effective shear viscosity coefficients of shocked iron are 3000 ± 100 Pa·s and 4000 ± 100 Pa·s, respectively, at 103 GPa and 159 GPa. These values are more than 2000 ± 300 Pa·s of Li Y L et al.[Chin. Phys. Lett. 26 (2009) 038301] Our values are more reasonable because they are obtained from a comprehensive simulation for the full-shocked perturbation evolving process. (fundamental areas of phenomenology(including applications))

  13. Constant load supports attenuating shocks and vibrations for networks of pipes submitted to large thermal dilatation

    International Nuclear Information System (INIS)

    Prisecaru, Ilie; Panait; Adrian; Serban, Viorel; Ciocan, George; Androne, Marian; Florea, Ioana; State, Elena

    2004-01-01

    Full text: To avoid some drawbacks in the classical supports employed currently in networks of pipes it was conceived, designed, built and experimentally tested a new type of constant load supports which attenuate largely the shocks and vibrations for networks of pipes subjected to large thermal dilatation. These supports are particularly needed for solving the severe problems of the vibrations in networks of pipes in thermoelectric stations, nuclear power plants, or heavy water production plants. These supports allow building networks of new types, more reliable and of lower cost. The new type of support was developed on the basis of a number of patents protected by OSIM. It has a simple structure, ensures a secure functioning without blocking or other kinds of failures and is resistant to a very large variety of stresses. The new type of support of constant load avoids the drawbacks in classical supports i.e. the stress/deformation diagram is practically independent of stress level. The characteristic of the support is geometrically non-linear and presents a plateau with a small slope over a rather large deformation range which results from a serially mounted structure of sandwiches the deformation of which is controlled by a system of deforming central and peripheral pieces. The new supports of constant load, called SERB-PIPE, present a controlled elasticity and a high degree of damping as the package of elastic blades (the sandwich structure) is made of two sub-packages with relative movements what ensure the attenuation of the shocks and vibrations produced by the fluid flow within the pipes and or by seismic motions. By contrast with classical supports, the new supports have a simple structure and a high reliability. Breakdown under stress leading to severe changes in the stress distribution in pipe networks, which could generate overloads in pipes and over-loading in other supports, cannot occur. One can also mention that these supports can be built in a

  14. Initial growth and texture formation during reactive magnetron sputtering of TiN on Si(111)

    CERN Document Server

    Li, T Q; Tsuji, Y; Ohsawa, T; Komiyama, H

    2002-01-01

    The initial growth and texture formation mechanism of titanium nitride (TiN) films were investigated by depositing TiN films on (111) silicon substrates by using reactive magnetron sputtering of a Ti metallic target under a N sub 2 /Ar atmosphere, and then analyzing the films in detail by using transmission electron microscopy (TEM) and x-ray diffraction (XRD). Two power sources for the sputtering, dc and rf, were compared. At the initial growth stage, a continuous amorphous film containing randomly oriented nuclei was observed when the film thickness was about 3 nm. The nuclei grew and formed a polycrystalline layer when the film thickness was about 6 nm. As the film grew further, its orientation changed depending on the deposition conditions. For dc sputtering, the appearance of (111) or (200)-preferred orientations depended on the N sub 2 partial pressure, and the intensity of the preferred orientation increased with increasing film thickness. For rf sputtering, however, when the film thickness was small (...

  15. Spray Pyrolyzed Polycrystalline Tin Oxide Thin Film as Hydrogen Sensor

    Directory of Open Access Journals (Sweden)

    Ganesh E. Patil

    2010-09-01

    Full Text Available Polycrystalline tin oxide (SnO2 thin film was prepared by using simple and inexpensive spray pyrolysis technique (SPT. The film was characterized for their phase and morphology by X-ray diffraction (XRD and scanning electron microscopy (SEM, respectively. The crystallite size calculated from the XRD pattern is 84 nm. Conductance responses of the polycrystalline SnO2 were measured towards gases like hydrogen (H2, liquefied petroleum gas (LPG, ethanol vapors (C2H5OH, NH3, CO, CO2, Cl2 and O2. The gas sensing characteristics were obtained by measuring the sensor response as a function of various controlling factors like operating temperature, operating voltages (1 V, 5 V, 10 V 15 V, 20 V and 25 V and concentration of gases. The sensor response measurement showed that the SnO2 has maximum response to hydrogen. Furthermore; the SnO2 based sensor exhibited fast response and good recovery towards hydrogen at temperature 150 oC. The result of response towards H2 reveals that SnO2 thin film prepared by SPT would be a suitable material for the fabrication of the hydrogen sensor.

  16. Simultaneous X-ray imaging and diffraction study of shock propagation and phase transition in silicon

    Science.gov (United States)

    Galtier, Eric

    2017-06-01

    X-ray phase contrast imaging technique using a free electron laser have observed the propagation of laser-driven shock waves directly inside materials. While providing images with few hundred nanometers spatial resolution, access to more quantitative information like the material density and the various shock front speeds remain challenging due to imperfections in the images limiting the convergence in the reconstruction algorithm. Alternatively, pump-probe X-ray diffraction (XRD) is a robust technique to extract atomic crystalline structure of compressed matter, providing insight into the kinetics of phase transformation and material response to stress. However, XRD by itself is not sufficient to extract the equation of state of the material under study. Here we report on the use of the LCLS free electron laser as a source of a high-resolution X-ray microscopy enabling the direct imaging of shock waves and phase transitions in optically opaque silicon. In this configuration, no algorithm is necessary to extract the material density and the position of the shock fronts. Simultaneously, we probed the crystalline structure via XRD of the various phases in laser compressed silicon. E. Galtier, B. Nagler, H. J. Lee, S. Brown, E. Granados, A. Hashim, E. McBride, A. Mackinnon, I. Nam, J. Zimmerman (SLAC) A. Gleason (Stanford, LANL) A. Higginbotham (University of York) A. Schropp, F. Seiboth (DESY).

  17. Chemistry of tin compounds and environment

    International Nuclear Information System (INIS)

    Ali, S.; Mazhar, M.; Mahmood, S.; Bhatti, M.H.; Chaudhary, M.A.

    1997-01-01

    Of the large volume of tin compounds reported in the literature, possible only 100 are commercially important. Tin compounds are a wide variety of purposes such as catalysts, stabilizers for many materials including polymer, biocidal agents, bactericides, insecticides, fungicides, wood preservatives, acaricides and anti fouling agents in paints, anticancer and antitumour agents, ceramic opacifiers, as textile additives, in metal finishing operations, as food additives and in electro conductive coating. All these applications make the environment much exposed to tin contamination. The application of organotin compounds as biocides account for about 30% of total tin consumption suggesting that the main environmental effects are likely to originate from this sector. Diorgano tins and mono-organo tins are used mainly in plastic industry which is the next big source for environmental pollution. In this presentation all environmental aspects of the use of tin compounds and the recommended preventive measures are discussed. (author)

  18. Measuring the sustainability of tin in China.

    Science.gov (United States)

    Yang, Congren; Tan, Quanyin; Zeng, Xianlai; Zhang, Yuping; Wang, Zhishi; Li, Jinhui

    2018-09-01

    Tin is a component of many items used in daily activities, including solder in consumer electronics, tin can containing food and beverages, polyvinyl chloride stabilizers in construction products, catalysts in industrial processes, etc. China is the largest producer and consumer of refined tin, and more than 60% of this refined tin is applied in the electronics sector as solder. China is the leader in global economic growth; simultaneously, China is also a major producer and consumer of electrical and electronic equipment (EEE). Thus, future tin supply and demand in China are forecasted, based on the gross domestic product per capita and the average consumption of refined tin in past five years. Current tin reserves and identified resources in China can meet the future two decades of mine production, but import of tin will also be critical for China's future tin consumption. However, there will be a lot of uncertainty for import of tin from other countries. At the same time, virgin mining of geological ores is a process of high energy consumption and destruction of the natural environment. Hence recycling tin from Sn-bearing secondary resources like tailings and waste electrical and electronic equipment (WEEE) can not only address the shortage of tin mineral resources, but also save energy and protect the ecological environment. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Diversity of Dominant Bacterial Taxa in Activated Sludge Promotes Functional Resistance following Toxic Shock Loading

    KAUST Repository

    Saikaly, Pascal

    2010-12-14

    Examining the relationship between biodiversity and functional stability (resistance and resilience) of activated sludge bacterial communities following disturbance is an important first step towards developing strategies for the design of robust biological wastewater treatment systems. This study investigates the relationship between functional resistance and biodiversity of dominant bacterial taxa by subjecting activated sludge samples, with different levels of biodiversity, to toxic shock loading with cupric sulfate (Cu[II]), 3,5-dichlorophenol (3,5-DCP), or 4-nitrophenol (4-NP). Respirometric batch experiments were performed to determine the functional resistance of activated sludge bacterial community to the three toxicants. Functional resistance was estimated as the 30 min IC50 or the concentration of toxicant that results in a 50% reduction in oxygen utilization rate compared to a referential state represented by a control receiving no toxicant. Biodiversity of dominant bacterial taxa was assessed using polymerase chain reaction-terminal restriction fragment length polymorphism (PCR-T-RFLP) targeting the 16S ribosomal RNA (16S rRNA) gene. Statistical analysis of 30 min IC50 values and PCR-T-RFLP data showed a significant positive correlation (P<0.05) between functional resistance and microbial diversity for each of the three toxicants tested. To our knowledge, this is the first study showing a positive correlation between biodiversity of dominant bacterial taxa in activated sludge and functional resistance. In this system, activated sludge bacterial communities with higher biodiversity are functionally more resistant to disturbance caused by toxic shock loading. © 2010 Springer Science+Business Media, LLC.

  20. Shock loading influence on mechanical behavior of high purity iron

    International Nuclear Information System (INIS)

    Buy, Francois; Voltz, Christophe

    2004-01-01

    This paper proposes the analysis of shock wave effects for high purity iron. The method developed is based on the characterization of the mechanical behavior of as received and shocked material. Shock effect is generated through plate impact tests performed in the range of 4 GPa to 39 GPa on a single stage light gas gun or a powder gun. Therefore, as-received and impacted materials are characterized. A formalism proposed by J.R.Klepaczko and based on physical relations has been adopted to describe stress strain curves

  1. Shock-induced chemistry in organic materials

    Energy Technology Data Exchange (ETDEWEB)

    Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Steve [Los Alamos National Laboratory; Engelke, Ray [Los Alamos National Laboratory; Manner, Virginia [Los Alamos National Laboratory; Chellappa, Raja [Los Alamos National Laboratory; Yoo, Choong - Shik [WASHINGTON STATE UNIV

    2011-01-20

    The combined 'extreme' environments of high pressure, temperature, and strain rates, encountered under shock loading, offer enormous potential for the discovery of new paradigms in chemical reactivity not possible under more benign conditions. All organic materials are expected to react under these conditions, yet we currently understand very little about the first bond-breaking steps behind the shock front, such as in the shock initiation of explosives, or shock-induced reactivity of other relevant materials. Here, I will present recent experimental results of shock-induced chemistry in a variety of organic materials under sustained shock conditions. A comparison between the reactivity of different structures is given, and a perspective on the kinetics of reaction completion under shock drives.

  2. Low-temperature Synthesis of Tin(II) Oxide From Tin(II) ketoacidoximate Precursor

    KAUST Repository

    Alshankiti, Buthainah

    2015-01-01

    Sn (II) oxide finds numerous applications in different fields such as thin film transistors1, solar cells2 and sensors.3 In this study we present the fabrication of tin monoxide SnO by using Sn (II) ketoacid oximate complexes as precursors. Tin (II

  3. Photocatalytic degradation of phenol by iodine doped tin oxide nanoparticles under UV and sunlight irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Al-Hamdi, Abdullah M.; Sillanpää, Mika [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Dutta, Joydeep, E-mail: dutta@squ.edu.om [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman)

    2015-01-05

    Highlights: • A sol–gel method used to synthesize tin oxide nanoparticles. • Nanoparticles of tin oxide doped with different iodine concentrations. • Degradation studies carried up with UV–vis, TOC, HPLC and GC instruments. • 1% iodine doped tin dioxide showed maximum photodegradation efficiency. - Abstract: Iodine doped tin oxide (SnO{sub 2}:I) nanoparticles were prepared by sol–gel synthesis and their photocatalytic activities with phenol as a test contaminant were studied. In the presence of the catalysts, phenol degradation under direct sunlight was comparable to what was achieved under laboratory conditions. Photocatalytic oxidation reactions were studied by varying the catalyst loading, light intensity, illumination time, pH of the reactant and phenol concentration. Upon UV irradiation in the presence of SnO{sub 2}:I nanoparticles, phenol degrades very rapidly within 30 min, forming carboxylic acid which turns the solution acidic. Phenol degradation rate with 1% iodine doped SnO{sub 2} nanoparticles is at least an order of magnitude higher compared to the degradation achieved through undoped SnO{sub 2} nanoparticles under similar illumination conditions.

  4. Photocatalytic degradation of phenol by iodine doped tin oxide nanoparticles under UV and sunlight irradiation

    International Nuclear Information System (INIS)

    Al-Hamdi, Abdullah M.; Sillanpää, Mika; Dutta, Joydeep

    2015-01-01

    Highlights: • A sol–gel method used to synthesize tin oxide nanoparticles. • Nanoparticles of tin oxide doped with different iodine concentrations. • Degradation studies carried up with UV–vis, TOC, HPLC and GC instruments. • 1% iodine doped tin dioxide showed maximum photodegradation efficiency. - Abstract: Iodine doped tin oxide (SnO 2 :I) nanoparticles were prepared by sol–gel synthesis and their photocatalytic activities with phenol as a test contaminant were studied. In the presence of the catalysts, phenol degradation under direct sunlight was comparable to what was achieved under laboratory conditions. Photocatalytic oxidation reactions were studied by varying the catalyst loading, light intensity, illumination time, pH of the reactant and phenol concentration. Upon UV irradiation in the presence of SnO 2 :I nanoparticles, phenol degrades very rapidly within 30 min, forming carboxylic acid which turns the solution acidic. Phenol degradation rate with 1% iodine doped SnO 2 nanoparticles is at least an order of magnitude higher compared to the degradation achieved through undoped SnO 2 nanoparticles under similar illumination conditions

  5. Investigation on the Mechanical and Tribological Properties of Aluminium-Tin Based Plain Bearing Material

    Directory of Open Access Journals (Sweden)

    T. Rameshkumar

    2010-06-01

    Full Text Available The purpose of this study is to investigate the Mechanical and Tribological properties of plain bearing alloys used especially in internal combustion engines. The mechanical properties namely Tensile strength and Hardness were investigated according to standard procedure. The sliding friction and wear properties of aluminium-tin alloy against high carbon high chromium steel were investigated at different normal loads as (29.43 N, 33.35 N and 36.25 N. Tests were carried in oil lubricated conditions with a sliding speed of 1 m/s. Prior to experimentation, the circulating engine oil 20w40 was heated to temperature of 800C using heater. The frictional behavior and wear property of aluminium-tin alloy were studied by means of pin-on-disk tribometer. The weight loss of the specimen was measured and wear and friction characteristics were calculated with respect to time, depth of wear track, sliding speed and bearing load. To determine the wear mechanism, the worn surfaces of the samples were examined using Scanning Electron Microscope (SEM. The optimum wear reduction was obtained at different normal loads and at same sliding speed.

  6. Unusual behaviour of usual materials in shock waves

    International Nuclear Information System (INIS)

    Kanel, G I

    2014-01-01

    Exotic results of investigations of inelastic deformation and fracture under shock wave loading are presented and briefly discussed. Temperature effects on the flow stress at high strain rate may differ even in sign from those we observe at low and moderate strain rates. Investigations of the temperature-rate dependence of the yield stress at shock compression demonstrate intense multiplication of dislocations. At the highest strain rates, so-called ideal (ultimate) shear and tensile strength is reached in experiments with picosecond durations of shock loading. Although grain boundaries, in general, reduce resistance to fracture as compared to single crystals, the spall strength of ultra-fine-grained metals usually slightly exceeds that of coarse-grain samples. Failure wave phenomena have been observed in shock-compressed glasses.

  7. Energetics of the terrestrial bow shock

    Science.gov (United States)

    Hamrin, Maria; Gunell, Herbert; Norqvist, Patrik

    2017-04-01

    The solar wind is the primary energy source for the magnetospheric energy budget. Energy can enter through the magnetopause both as kinetic energy (plasma entering via e.g. magnetic reconnection and impulsive penetration) and as electromagnetic energy (e.g. by the conversion of solar wind kinetic energy into electromagnetic energy in magnetopause generators). However, energy is extracted from the solar wind already at the bow shock, before it encounters the terrestrial magnetopause. At the bow shock the supersonic solar wind is slowed down and heated, and the region near the bow shock is known to host many complex processes, including the accelerating of particles and the generation of waves. The processes at and near the bow shock can be discussed in terms of energetics: In a generator (load) process kinetic energy is converted to (from) electromagnetic energy. Bow shock regions where the solar wind is decelerated correspond to generators, while regions where particles are energized (accelerated and heated) correspond to loads. Recently, it has been suggested that currents from the bow shock generator should flow across the magnetosheath and connect to the magnetospause current systems [Siebert and Siscoe, 2002; Lopez et al., 2011]. In this study we use data from the Magnetospheric MultiScale (MMS) mission to investigate the energetics of the bow shock and the current closure, and we compare with the MHD simulations of Lopez et al., 2011.

  8. The use of micro-XRD for the study of glaze color decorations

    Energy Technology Data Exchange (ETDEWEB)

    Pradell, T.; Molina, G. [Universitat Politecnica de Catalunya, Dpt. Fisica i Enginyeria Nuclear, Castelldefels (Spain); Molera, J.; Pla, J. [Universitat de Vic, GRTD, Escola Politecnica Superior, Vic (Spain); Labrador, A. [BM16-ESRF, LLS, BP 220, Grenoble Cedex (France); Lund University, MAX IV Laboratory, Lund (Sweden)

    2013-04-15

    The compounds responsible for the colors and decorations in glass and glazed ceramics include: coloring agents (transition-metal ions), pigments (micro- and nanoprecipitates of compounds that either do not dissolve or recrystallize in the glassy matrix) and opacifiers (microcrystalline compounds with high light scattering capability). Their composition, structure and range of stability are highly dependent not only on the composition but also on the procedures followed to obtain them. Chemical composition of the colorants and crystallites may be obtained by means of SEM-EDX and WDX. Synchrotron radiation micro-X-ray diffraction (SR-micro-XRD) has a small beam size adequate (10 to 50 microns footprint size) to obtain the structural information of crystalline compounds and high brilliance, optimal for determining the crystallites even when present in low amounts. In addition, in glass decorations the crystallites often appear forming thin layers (from 10 to 100 micrometers thick) and they show a depth-dependent composition and crystal structure. Their nature and distribution across the glass/glaze decorations gives direct information on the technology of production and stability and may be related to the color and appearance. A selection of glass and glaze coloring agents and decorations are studied by means of SR-micro-XRD and SEM-EDX including: manganese brown, antimony yellow, red copper lusters and cobalt blue. The selection includes Medieval (Islamic, and Hispano Moresque) and Renaissance tin-glazed ceramics from the 10th to the 17th century AD. (orig.)

  9. Thermal shock behavior of W-0.5 wt% Y_2O_3 alloy prepared via a novel chemical method

    International Nuclear Information System (INIS)

    Zhao, Mei-Ling; Luo, Lai-Ma; Lin, Jing-Shan; Zan, Xiang; Zhu, Xiao-Yong; Luo, Guang-Nan; Wu, Yu-Cheng

    2016-01-01

    A wet-chemical method combined with spark plasma sintering was used to prepare W-0.5 wt% Y_2O_3 alloy. The W-0.5 wt% Y_2O_3 precursor was reduced at 800 °C for 4 h under different hydrogen flow rates of 300, 400, 500, 600, and 700 ml/min. The reduced powder was analyzed by X-ray diffraction (XRD), laser particle size analyzer (LPSA), and scanning electron microscopy (SEM). An optimized process for reducing precursor was discussed. After sintering, the specimens were exposed to different laser beam irradiation energies (90, 120, 150, and 180 W) to simulate loads as expected for edge localized modes (ELMs). Top surface and cross-sectional morphology were observed by SEM, and the changes in hardness were evaluated. The changes in microstructural properties (i.e., Y_2O_3-particle distribution, crack propagation direction, depth of thermal shock effect, and grain size of the recrystallization region) after thermal shock were investigated.

  10. Comparative Analysis of Data Structures for Storing Massive Tins in a Dbms

    Science.gov (United States)

    Kumar, K.; Ledoux, H.; Stoter, J.

    2016-06-01

    Point cloud data are an important source for 3D geoinformation. Modern day 3D data acquisition and processing techniques such as airborne laser scanning and multi-beam echosounding generate billions of 3D points for simply an area of few square kilometers. With the size of the point clouds exceeding the billion mark for even a small area, there is a need for their efficient storage and management. These point clouds are sometimes associated with attributes and constraints as well. Storing billions of 3D points is currently possible which is confirmed by the initial implementations in Oracle Spatial SDO PC and the PostgreSQL Point Cloud extension. But to be able to analyse and extract useful information from point clouds, we need more than just points i.e. we require the surface defined by these points in space. There are different ways to represent surfaces in GIS including grids, TINs, boundary representations, etc. In this study, we investigate the database solutions for the storage and management of massive TINs. The classical (face and edge based) and compact (star based) data structures are discussed at length with reference to their structure, advantages and limitations in handling massive triangulations and are compared with the current solution of PostGIS Simple Feature. The main test dataset is the TIN generated from third national elevation model of the Netherlands (AHN3) with a point density of over 10 points/m2. PostgreSQL/PostGIS DBMS is used for storing the generated TIN. The data structures are tested with the generated TIN models to account for their geometry, topology, storage, indexing, and loading time in a database. Our study is useful in identifying what are the limitations of the existing data structures for storing massive TINs and what is required to optimise these structures for managing massive triangulations in a database.

  11. Investigation of a Shock Absorber for Safeguard of Fuel Assemblies Failure

    International Nuclear Information System (INIS)

    Karalevicius, Renatas; Dundulis, Gintautas; Rimkevicius, Sigitas; Uspuras, Eugenijus

    2006-01-01

    The Ignalina NPP has two reactors. The Unit 1 was shut down, therefore the special equipment was designed for transportation of the fuel from Unit 1 to Unit 2. The fuel-loaded basket can drop during transportation. The special shock absorber was designed in order to avoid failure of fuel assemblies during transportation. In case of drop of fuel loaded basket, the failure of fuel assemblies can occur. This shock absorber was studied by scaled experiments at Lithuanian Energy Institute. Static and dynamic investigations of shock absorber are presented in this paper, including dependency of axial force versus axial compression. The finite element codes BRIGADE/Plus and ABAQUS/Explicit were used for analysis. Static simulation was used to optimize the dimensions of shock absorber. Dynamic analysis shows that shock absorber is capable to withstand the dynamic load for successful force suppression function in case of an accident. (authors)

  12. Transient Three-Dimensional Analysis of Nozzle Side Load in Regeneratively Cooled Engines

    Science.gov (United States)

    Wang, Ten-See

    2005-01-01

    Three-dimensional numerical investigations on the start-up side load physics for a regeneratively cooled, high-aspect-ratio nozzle were performed. The objectives of this study are to identify the three-dimensional side load physics and to compute the associated aerodynamic side load using an anchored computational methodology. The computational methodology is based on an unstructured-grid, pressure-based computational fluid dynamics formulation, and a transient inlet condition based on an engine system simulation. Computations were performed for both the adiabatic and cooled walls in order to understand the effect of boundary conditions. Finite-rate chemistry was used throughout the study so that combustion effect is always included. The results show that three types of shock evolution are responsible for side loads: generation of combustion wave; transitions among free-shock separation, restricted-shock separation, and simultaneous free-shock and restricted shock separations; along with oscillation of shocks across the lip. Wall boundary conditions drastically affect the computed side load physics: the adiabatic nozzle prefers free-shock separation while the cooled nozzle favors restricted-shock separation, resulting in higher peak side load for the cooled nozzle than that of the adiabatic nozzle. By comparing the computed physics with those of test observations, it is concluded that cooled wall is a more realistic boundary condition, and the oscillation of the restricted-shock separation flow pattern across the lip along with its associated tangential shock motion are the dominant side load physics for a regeneratively cooled, high aspect-ratio rocket engine.

  13. Structural studies of supported tin catalysts

    Science.gov (United States)

    Nava, Noel; Viveros, Tomás

    1999-11-01

    Tin oxide was supported on aluminium oxide, titanium oxide, magnesium oxide and silicon oxide, and the resulting interactions between the components in the prepared samples and after reduction were characterized by Mössbauer spectroscopy. It was observed that in the oxide state, tin is present as SnO2 on alumina, magnesia and silica, but on titania tin occupies Ti sites in the structure. After hydrogen treatment at high temperatures, tin is reduced from Sn(4) to Sn(2) on alumina and titania; it is reduced from Sn(4) to Sn(0) on silica, and is practically not reduced on magnesia. These results reveal the degree of interaction between tin and the different supports studied.

  14. Structural studies of supported tin catalysts

    International Nuclear Information System (INIS)

    Nava, Noel; Viveros, Tomas

    1999-01-01

    Tin oxide was supported on aluminium oxide, titanium oxide, magnesium oxide and silicon oxide, and the resulting interactions between the components in the prepared samples and after reduction were characterized by Moessbauer spectroscopy. It was observed that in the oxide state, tin is present as SnO 2 on alumina, magnesia and silica, but on titania tin occupies Ti sites in the structure. After hydrogen treatment at high temperatures, tin is reduced from Sn(4) to Sn(2) on alumina and titania; it is reduced from Sn(4) to Sn(0) on silica, and is practically not reduced on magnesia. These results reveal the degree of interaction between tin and the different supports studied

  15. An Enzymatic Glucose Sensor Composed of Carbon-Coated Nano Tin Sulfide

    Directory of Open Access Journals (Sweden)

    Ren-Jei Chung

    2017-02-01

    Full Text Available In this study, a biosensor, based on a glucose oxidase (GOx immobilized, carbon-coated tin sulfide (SnS assembled on a glass carbon electrode (GCE was developed, and its direct electrochemistry was investigated. The carbon coated SnS (C-SnS nanoparticle was prepared through a simple two-step process, using hydrothermal and chemical vapor deposition methods. The large reactive surface area and unique electrical potential of C-SnS could offer a favorable microenvironment for facilitating electron transfer between enzymes and the electrode surface. The structure and sensor ability of the proposed GOx/C-SnS electrode were characterized using scanning electron microscopy (SEM, X-ray diffraction (XRD, Raman spectroscopy, UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR, and cyclic voltammetry study (CV.

  16. Mn-implanted, polycrystalline indium tin oxide and indium oxide films

    International Nuclear Information System (INIS)

    Scarlat, Camelia; Vinnichenko, Mykola; Xu Qingyu; Buerger, Danilo; Zhou Shengqiang; Kolitsch, Andreas; Grenzer, Joerg; Helm, Manfred; Schmidt, Heidemarie

    2009-01-01

    Polycrystalline conducting, ca. 250 nm thick indium tin oxide (ITO) and indium oxide (IO) films grown on SiO 2 /Si substrates using reactive magnetron sputtering, have been implanted with 1 and 5 at.% of Mn, followed by annealing in nitrogen or in vacuum. The effect of the post-growth treatment on the structural, electrical, magnetic, and optical properties has been studied. The roughness of implanted films ranges between 3 and 15 nm and XRD measurements revealed a polycrystalline structure. A positive MR has been observed for Mn-implanted and post-annealed ITO and IO films. It has been interpreted by considering s-d exchange. Spectroscopic ellipsometry has been used to prove the existence of midgap electronic states in the Mn-implanted ITO and IO films reducing the transmittance below 80%.

  17. Electrodeposition of white copper-tin alloys from alkaline cyanide solutions

    International Nuclear Information System (INIS)

    Purwadaria, H.S.; Zainal Arifin Ahmad

    2007-01-01

    Electrodeposition of white copper-tin alloys (including with mir alloys) has been done onto planar mild steel substrates from alkaline cyanide solutions at 65 degree C. The chemical composition of the coating is influenced by plating bath composition and current density. White mir alloy can be produced from the test solution containing 10 g/l CuCN 2 ,45 g/l Na 2 SnO 3 , 25 g/l NaCN, and 12 g/l NaOH at current density about 5 mA/cm?2. The local compositions of the coating cross section were analyzed using EDX installed in a FESEM operated at an accelerating voltage of 20 kV. The phases formed during co-deposition process were identified using XRD at 25 mA current and 35 kV voltage. (Author)

  18. Coupled Fluid-Solid Interaction Under Shock Wave Loading: Part II - Dynamic Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Tipton, David Gregory [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Christon, Mark Allen [CTO Offce, Dassault Systµemes SIMULIA, Providence, RI (United States); Ingber, Marc Stuart [Univ. of New Mexico, Albuquerque, NM (United States). Department of Mechanical Engineering

    2009-07-01

    This article is the second of two that consider the treatment of fluid-solid interaction problems where the solid experiences wave loading and large bulk Lagrangian displacements. In part-I, we presented the formulation for the edge-based unstructured-grid Euler solver in the context of a discontinuous- Galerkin framework with the extensions used to treat internal fluid-solid interfaces. A super-sampled L2 projection was used to construct level-set data from the Lagrangian interface, and a narrow-band approach was used to identify and construct appropriate ghost data and boundary conditions at the fluid-solid interface. A series of benchmark problems were used to verify the treatment of the fluid-solid interface conditions with a static interface position. In this paper, we consider the treatment of dynamic interfaces and the associated large bulk Lagrangian displacements of the solid.We present the coupled dynamic fluid-solid system, and develop an explicit, monolithic treatment of the fully-coupled system. The conditions associated with moving interfaces and their implementation are discussed. A comparison of moving vs. fixed reference frames is used to verify the dynamic interface treatment. Lastly, a series of two and and three-dimensional projectile and shock-body interaction calculations are presented. Ultimately, the use of the Lagrangian interface position and a super-sampled projection for fast level-set construction, the narrow-band extraction of ghost data, and monolithic explicit solution algorithm has proved to be a computationally efficient means for treating shock induced fluid-solid interaction problems.

  19. Spall wave-profile and shock-recovery experiments on depleted uranium

    International Nuclear Information System (INIS)

    Hixson, R.S.; Vorthman, J.E.; Gustavsen, R.L.; Zurek, A.K.; Thissell, W.R.; Tonks, D.L.

    1998-01-01

    Depleted Uranium of two different purity levels has been studied to determine spall strength under shock wave loading. A high purity material with approximately 30 ppm of carbon impurities was shock compressed to two different stress levels, 37 and 53 kbar. The second material studied was uranium with about 300 ppm of carbon impurities. This material was shock loaded to three different final stress level, 37, 53, and 81 kbar. Two experimental techniques were used in this work. First, time-resolved free surface particle velocity measurements were done using a VISAR velocity interferometer. The second experimental technique used was soft recovery of samples after shock loading. These two experimental techniques will be briefly described here and VISAR results will be shown. Results of the spall recovery experiments and subsequent metallurgical analyses are described in another paper in these proceedings. copyright 1998 American Institute of Physics

  20. Power law and exponential ejecta size distributions from the dynamic fragmentation of shock-loaded Cu and Sn metals under melt conditions

    Energy Technology Data Exchange (ETDEWEB)

    Durand, O.; Soulard, L. [CEA, DAM, DIF, F-91297 Arpajon (France)

    2013-11-21

    Large scale molecular dynamics (MD) simulations are performed to study and to model the ejecta production from the dynamic fragmentation of shock-loaded metals under melt conditions. A generic 3D crystal in contact with vacuum containing about 10{sup 8} atoms and with a sinusoidal free surface roughness is shock loaded so as to undergo a solid-liquid phase change on shock. The reflection of the shock wave at the interface metal/vacuum gives rise to the ejection of 2D jets/sheets of atoms (Richtmyer-Meshkov instabilities in the continuum limit), which develop and break up, forming ejecta (fragments) of different volumes (or mass). The fragmentation process is investigated by analyzing the evolution of the resulting volume distribution of the ejecta as a function of time. Two metals are studied (Cu and Sn) and the amplitude of the roughness is varied. The simulations show that the associated distributions exhibit a generic behavior with the sum of two distinct terms of varying weight, following the expansion rate of the jets: in the small size limit, the distribution obeys a power law dependence with an exponent equal to 1.15 ± 0.08; and in the large size limit, it obeys an exponential form. These two components are interpreted, with the help of additional simple simulations, as the signature of two different basic mechanisms of fragmentation. The power law dependence results from the fragmentation of a 2D network of ligaments arranged following a fractal (scale free) geometry and generated when the sheets of liquid metal expand and tear. The exponential distribution results from a 1D Poisson fragmentation process of the largest ligaments previously generated. Unlike the power law distribution, it is governed by a characteristic length scale, which may be provided by energy balance principle.

  1. Power law and exponential ejecta size distributions from the dynamic fragmentation of shock-loaded Cu and Sn metals under melt conditions

    International Nuclear Information System (INIS)

    Durand, O.; Soulard, L.

    2013-01-01

    Large scale molecular dynamics (MD) simulations are performed to study and to model the ejecta production from the dynamic fragmentation of shock-loaded metals under melt conditions. A generic 3D crystal in contact with vacuum containing about 10 8 atoms and with a sinusoidal free surface roughness is shock loaded so as to undergo a solid-liquid phase change on shock. The reflection of the shock wave at the interface metal/vacuum gives rise to the ejection of 2D jets/sheets of atoms (Richtmyer-Meshkov instabilities in the continuum limit), which develop and break up, forming ejecta (fragments) of different volumes (or mass). The fragmentation process is investigated by analyzing the evolution of the resulting volume distribution of the ejecta as a function of time. Two metals are studied (Cu and Sn) and the amplitude of the roughness is varied. The simulations show that the associated distributions exhibit a generic behavior with the sum of two distinct terms of varying weight, following the expansion rate of the jets: in the small size limit, the distribution obeys a power law dependence with an exponent equal to 1.15 ± 0.08; and in the large size limit, it obeys an exponential form. These two components are interpreted, with the help of additional simple simulations, as the signature of two different basic mechanisms of fragmentation. The power law dependence results from the fragmentation of a 2D network of ligaments arranged following a fractal (scale free) geometry and generated when the sheets of liquid metal expand and tear. The exponential distribution results from a 1D Poisson fragmentation process of the largest ligaments previously generated. Unlike the power law distribution, it is governed by a characteristic length scale, which may be provided by energy balance principle

  2. Physicochemical characterization of point defects in fluorine doped tin oxide films

    Science.gov (United States)

    Akkad, Fikry El; Joseph, Sudeep

    2012-07-01

    The physical and chemical properties of spray deposited FTO films are studied using FESEM, x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), electrical and optical measurements. The results of XRD measurements showed that the films are polycrystalline (grain size 20-50 nm) with Rutile structure and mixed preferred orientation along the (200) and (110) planes. An angular shift of the XRD peaks after F-doping is observed and interpreted as being due to the formation of substitutional fluorine defects (FO) in presence of high concentration of oxygen vacancies (VO) that are electrically neutral. The electrical neutrality of oxygen vacancies is supported by the observation that the electron concentration n is two orders of magnitude lower than the VO concentration calculated from chemical analyses using XPS measurements. It is shown that an agreement between XPS, XRD, and Hall effect results is possible provided that the degree of deviation from stoichiometry is calculated with the assumption that the major part of the bulk carbon content is involved in O-C bonds. High temperature thermal annealing is found to cause an increase in the FO concentration and a decrease in both n and VO concentrations with the increase of the annealing temperature. These results could be interpreted in terms of a high temperature chemical exchange reaction between the SnO2 matrix and a precipitated fluoride phase. In this reaction, fluorine is released to the matrix and Sn is trapped by the fluoride phase, thus creating substitutional fluorine FO and tin vacancy VSn defects. The enthalpy of this reaction is determined to be approximately 2.4 eV while the energy of formation of a VSn through the migration of SnSn host atom to the fluoride phase is approximately 0.45 eV.

  3. Influences of Traction Load Shock on Artificial Partial Discharge Faults within Traction Transformer—Experimental Test for Pattern Recognition

    Directory of Open Access Journals (Sweden)

    Shuaibing Li

    2017-10-01

    Full Text Available Partial discharge (PD measurement and its pattern recognition are vital to fault diagnosis of transformers, especially to those traction substation transformers undergoing repetitive traction load shocks. This paper presents the primary factors induced by traction load shocks including high total harmonics distortion (THD, transient voltage impulse and high-temperature rise, and their effects on the feature parameters of PD. Experimental tests are conducted on six artificial PD models with these factors introduced one by one. Results reveal that the maximum PD quantity and the PD repetitive rate are favorable to be enlarged when the oil temperature exceeds 80 °C or the THD is higher than 16% with certain orders of harmonic. The decline in PD inception voltage can mainly be attributed to the transient voltage impulse. The variation in central frequency of the fast Fourier transformation (FFT spectra transformed from ultra-high frequency signals can mainly be attributed to high THD, especially when it exceeds 20%. The temperature rise has no significant influence on the FFT spectra; the transient voltage impulse, however, can result in a central frequency shift of the floating particle discharge. With the rapid development of high-speed railways, the study presented in this paper will be helpful for field PD detection and recognition of traction substation transformers in the future.

  4. Plane shock loading on mono- and nano-crystalline silicon carbide

    Science.gov (United States)

    Branicio, Paulo S.; Zhang, Jingyun; Rino, José P.; Nakano, Aiichiro; Kalia, Rajiv K.; Vashishta, Priya

    2018-03-01

    The understanding of the nanoscale mechanisms of shock damage and failure in SiC is essential for its application in effective and damage tolerant coatings. We use molecular-dynamics simulations to investigate the shock properties of 3C-SiC along low-index crystallographic directions and in nanocrystalline samples with 5 nm and 10 nm grain sizes. The predicted Hugoniot in the particle velocity range of 0.1 km/s-6.0 km/s agrees well with experimental data. The shock response transitions from elastic to plastic, predominantly deformation twinning, to structural transformation to the rock-salt phase. The predicted strengths from 12.3 to 30.9 GPa, at the Hugoniot elastic limit, are in excellent agreement with experimental data.

  5. The role of tin-promoted Pd/MWNTs via the management of carbonaceous species in selective hydrogenation of high concentration acetylene

    International Nuclear Information System (INIS)

    Esmaeili, Elaheh; Mortazavi, Yadollah; Khodadadi, Abbas Ali; Rashidi, Ali Morad; Rashidzadeh, Mehdi

    2012-01-01

    Highlights: ► Synthesis of highly active tin-promoted catalysts by polyol method for selective hydrogenation of high concentration of acetylene. ► A positive change in the catalytic activities of tin-promoted catalysts results from distinct geometric and electronic effects. ► Change in the coverage of acetylenic overlayers for different temperature regions corresponds to the change of the number of isolated adsorption sites. ► The isolated adsorption sites are responsible for the enhancement of selectivity to ethylene with increased temperatures, via the management of the carbonaceous species over the catalyst surface. - Abstract: In the present study, Pd/MWNTs are synthesized using polyol process and modified by tin as a promoter for selective hydrogenation of high concentrated acetylene feedstock. Polyol method results in highly dispersed nanoparticles with a depletion of particle size for tin-promoted Pd catalysts as characterized by TEM. Tin promoter plays a considerable role in hydrogenation of pure acetylene stream. This is attributed to formation of Pd 2 Sn structural phase, confirmed by XRD and TPR techniques, composed mainly of intermetallic species. Catalytic behavior of tin-promoted Pd catalysts is affected by geometric and electronic factors which are more pronounced in the case of Sn/Pd = 0.25. A discontinuity in Arrhenius plots for the Sn-promoted catalysts is appeared, which seems to be due to a kinetic factor as a result of change in acetylene coverage on Pd metallic ensembles at low and high temperature ranges. Higher selectivity of the catalysts to ethylene is attributed to the presence of more isolated adsorption sites on the catalyst surface originated from both intermetallic compounds confirmed by XPS and the ones formed via the carbonaceous species upon the acetylene hydrogenation reaction.

  6. 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

  7. Ultrafast dynamic ellipsometry and spectroscopies of laser shocked materials

    Energy Technology Data Exchange (ETDEWEB)

    Mcgrane, Shawn David [Los Alamos National Laboratory; Bolme, Cindy B [Los Alamos National Laboratory; Whitley, Von H [Los Alamos National Laboratory; Moore, David S [Los Alamos National Laboratory

    2010-01-01

    Ultrafast ellipsometry and transient absorption spectroscopies are used to measure material dynamics under extreme conditions of temperature, pressure, and volumetric compression induced by shock wave loading with a chirped, spectrally clipped shock drive pulse.

  8. Electrochemical dissolution of tin in methanesulphonic acid solutions

    NARCIS (Netherlands)

    de Greef, R.A.T.; Janssen, L.J.J.

    2001-01-01

    High-rate electroplating of tin on a moving steel strip is generally carried out in cells with dimensionally stable anodes. To obtain a matt tin deposit a concentrated acidic tin methanesulphonate solution containing a small concentration of sulphuric acid is used. The concentrated tin

  9. Shock therapy: Gris Gun's shock absorber can take the punch

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2000-04-01

    A newly developed shock impedance tool that isolates downhole tools that measure the effects of well stimulation techniques from being damaged by the violent shaking caused by various well stimulation techniques which combine perforating and propellant technology in a single tool, is discussed. The shock exerted by a perforating gun can exceed 25,000 G forces within 100 to 300 milliseconds, may damage or even destroy the sensitive electronics housed in the various recorders that record data about fracture gradients, permeability and temperature. The shock absorber developed by Tesco Gris Gun and Computalog, incorporates the mechanics of a piston style shock absorber in combination with a progressive spring stack and energy-dampening silicone oil chambers. The end results is an EUE 'slim line' assembly that is adaptable between the gun perforating string and the electronic equipment. It is typically attached below, reducing the shock load by as much as 90 per cent. The shock absorber is now available commercially through Gris Gun's exclusive distributorship. An improved version, currently under development, will be used for wireline perforating and tubing-conveyed perforating applications. 2 figs.

  10. Comparison of mechanical behavior of TiN, TiNC, CrN/TiNC, TiN/TiNC films on 9Cr18 steel by PVD

    Science.gov (United States)

    Feng, Xingguo; Zhang, Yanshuai; Hu, Hanjun; Zheng, Yugang; Zhang, Kaifeng; Zhou, Hui

    2017-11-01

    TiN, TiNC, CrN/TiNC and TiN/TiNC films were deposited on 9Cr18 steel using magnetron sputtering technique. The morphology, composition, chemical state and crystalline structure of the films were observed and analyzed by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Hardness and adhesion force were tested by nanoindentation and scratch tester, respectively. The friction and wear behavior of TiN, TiNC, CrN/TiNC and TiN/TiNC films sliding against GCr15 balls were investigated and compared synthetically using ball-on-disk tribometer. It was found that Tisbnd N, Tisbnd C, Tisbnd Nsbnd C and Csbnd C bonds were formed. The TiN/TiNC film was composed of TiN, TiC and TiNC phases. Hardness and adhesion force results indicated that although the TiN film possessed the highest hardness, its adhesion force was lowest among all the films. Tribological test results showed that the friction coefficient of TiN/TiNC was much lower than that of TiN and the wear rate decreases remarkably from 2.3 × 10-15 m3/Nm to 7.1 × 10-16 m3/Nm, which indicated the TiN/TiNC film has better wear resistance.

  11. Polycrystalline Mn-alloyed indium tin oxide films

    International Nuclear Information System (INIS)

    Scarlat, Camelia; Schmidt, Heidemarie; Xu, Qingyu; Vinnichenko, Mykola; Kolitsch, Andreas; Helm, Manfred; Iacomi, Felicia

    2008-01-01

    Magnetic ITO films are interesting for integrating ITO into magneto-optoelectronic devices. We investigated n-conducting indium tin oxide (ITO) films with different Mn doping concentration which have been grown by chemical vapour deposition using targets with the atomic ratio In:Sn:Mn=122:12:0,114:12:7, and 109:12:13. The average film roughness ranges between 30 and 50 nm and XRD patterns revealed a polycrystalline structure. Magnetotransport measurements revealed negative magnetoresistance for all the samples, but high field positive MR can be clearly observed at 5 K with increasing Mn doping concentration. Spectroscopic ellipsometry (SE) has been used to prove the existence of midgap states in the Mn-alloyed ITO films revealing a transmittance less than 80%. A reasonable model for the ca. 250 nm thick Mn-alloyed ITO films has been developed to extract optical constants from SE data below 3 eV. Depending on the Mn content, a Lorentz oscillator placed between 1 and 2 eV was used to model optical absorption below the band gap

  12. COMPARATIVE ANALYSIS OF DATA STRUCTURES FOR STORING MASSIVE TINS IN A DBMS

    Directory of Open Access Journals (Sweden)

    K. Kumar

    2016-06-01

    Full Text Available Point cloud data are an important source for 3D geoinformation. Modern day 3D data acquisition and processing techniques such as airborne laser scanning and multi-beam echosounding generate billions of 3D points for simply an area of few square kilometers. With the size of the point clouds exceeding the billion mark for even a small area, there is a need for their efficient storage and management. These point clouds are sometimes associated with attributes and constraints as well. Storing billions of 3D points is currently possible which is confirmed by the initial implementations in Oracle Spatial SDO PC and the PostgreSQL Point Cloud extension. But to be able to analyse and extract useful information from point clouds, we need more than just points i.e. we require the surface defined by these points in space. There are different ways to represent surfaces in GIS including grids, TINs, boundary representations, etc. In this study, we investigate the database solutions for the storage and management of massive TINs. The classical (face and edge based and compact (star based data structures are discussed at length with reference to their structure, advantages and limitations in handling massive triangulations and are compared with the current solution of PostGIS Simple Feature. The main test dataset is the TIN generated from third national elevation model of the Netherlands (AHN3 with a point density of over 10 points/m2. PostgreSQL/PostGIS DBMS is used for storing the generated TIN. The data structures are tested with the generated TIN models to account for their geometry, topology, storage, indexing, and loading time in a database. Our study is useful in identifying what are the limitations of the existing data structures for storing massive TINs and what is required to optimise these structures for managing massive triangulations in a database.

  13. 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.

  14. Tin-antimony oxide oxidation catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Berry, Frank J. [Open University, Department of Chemistry (United Kingdom)

    1998-12-15

    Tin-antimony oxide catalysts for the selective oxidation of hydrocarbons have been made by precipitation techniques. The dehydration of the amorphous dried precipitate by calcination at increasingly higher temperatures induces the crystallisation of a rutile-related tin dioxide-type phase and the segregation of antimony oxides which volatilise at elevated temperatures. The rutile-related tin dioxide-type phase contains antimony(V) in the bulk and antimony(III) in the surface. Specific catalytic activity for the oxidative dehydrogenation of butene to butadiene is associated with materials with large concentrations of antimony(III) in the surface.

  15. Combined XRD and XAS

    International Nuclear Information System (INIS)

    Ehrlich, S.N.; Hanson, J.C.; Lopez Camara, A.; Barrio, L.; Estrella, M.; Zhou, G.; Si, R.; Khalid, S.; Wang, Q.

    2011-01-01

    X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) are complementary techniques for investigating the structure of materials. XRD probes long range order and XAFS probes short range order. We have combined the two techniques at one synchrotron beamline, X18A at the NSLS, allowing samples to be studied in a single experiment. This beamline will allow for coordinated measurements of local and long range structural changes in chemical transformations and phase transitions using both techniques.

  16. Growth and characterization of tin disulfide (SnS2) thin film deposited by successive ionic layer adsorption and reaction (SILAR) technique

    International Nuclear Information System (INIS)

    Deshpande, N.G.; Sagade, A.A.; Gudage, Y.G.; Lokhande, C.D.; Sharma, Ramphal

    2007-01-01

    Thin films of tin disulfide (SnS 2 ) have been deposited by using low cost successive ionic layer adsorption and reaction (SILAR) technique. The deposition parameters such as SILAR cycles (60), immersion time (20 s), rinsing time (10 s) and deposition temperature (27 o C) were optimized to obtain good quality of films. Physical investigations were made to study the structural, optical and electrical properties. X-ray diffraction (XRD) patterns reveal that the deposited SnS 2 thin films have hexagonal crystal structure. Energy dispersive X-ray analysis (EDAX) indicated elemental ratio close to those for tin disulfide (SnS (2.02) ). Uniform deposition of the material over the entire glass substrate was revealed by scanning electron microscopy (SEM). Atomic force microscopy (AFM) showed the film is uniform and the substrate surface is well covered with small spherical grains merged in each other. A direct band gap of 2.22 eV was obtained. Photoluminescence (PL) showed two strong peaks corresponding to green and red emission. Ag/SnS 2 junction showed Schottky diode like I-V characteristics. The barrier height calculated was 0.22 eV. Thermoelectric power (TEP) properties showed that tin disulfide exhibits n-type conductivity

  17. Influence of shock absorber condition on pavement fatigue using relative damage concept

    Directory of Open Access Journals (Sweden)

    Pablo Kubo

    2015-12-01

    Full Text Available Considering the importance of the road transportation nowadays, concerns related to pavement deterioration and maintenance have become relevant subjects. Especially for commercial vehicles, the vertical dynamic load (characterized by the tire-road interaction is directly related to wear on the road surface. Given this, the main objective of this paper is to analyse effects of vertical loads applied on the flexible pavement, considering the variation of the condition of shock absorbers from a truck's front suspension. The measurements were performed on a rigid truck, with 2 steering front axles, in a durability test track located in Brazil. With a constant load of 6 tons on the front suspension (the maximum allowed load on front axles according to Brazilian legislation, 3 different shock absorber conditions were evaluated: new, used and failed. By applying the relative damage concept, it is possible to conclude that the variation of the shock absorber conditions will significantly affect the vertical load applied on the pavement. Although the results clearly point to a dependent relationship between the load and the condition of the shock absorbers, it is recommended to repeat the same methodology, in future to analyse the influence of other quarter car model variants (such as spring rate, mass and tire spring stiffness.

  18. Shock interactions with heterogeneous energetic materials

    Science.gov (United States)

    Yarrington, Cole D.; Wixom, Ryan R.; Damm, David L.

    2018-03-01

    The complex physical phenomenon of shock wave interaction with material heterogeneities has significant importance and nevertheless remains little understood. In many materials, the observed macroscale response to shock loading is governed by characteristics of the microstructure. Yet, the majority of computational studies aimed at predicting phenomena affected by these processes, such as the initiation and propagation of detonation waves in explosives or shock propagation in geological materials, employ continuum material and reactive burn model treatment. In an effort to highlight the grain-scale processes that underlie the observable effects in an energetic system, a grain-scale model for hexanitrostilbene (HNS) has been developed. The measured microstructures were used to produce synthetic computational representations of the pore structure, and a density functional theory molecular dynamics derived equation of state (EOS) was used for the fully dense HNS matrix. The explicit inclusion of the microstructure along with a fully dense EOS resulted in close agreement with historical shock compression experiments. More recent experiments on the dynamic reaction threshold were also reproduced by inclusion of a global kinetics model. The complete model was shown to reproduce accurately the expected response of this heterogeneous material to shock loading. Mesoscale simulations were shown to provide a clear insight into the nature of threshold behavior and are a way to understand complex physical phenomena.

  19. One step aqueous solution preparation of nanosize iron-doped tin oxide from SnO{sub 2}.xH{sub 2}O gel

    Energy Technology Data Exchange (ETDEWEB)

    Melghit, Khaled [Chemistry Department, College of Science, P.O. Box 36, Al-Khodh 123, Sultan Qaboos University (Oman)]. E-mail: melghit@squ.edu.om; Bouziane, Khalid [Physics Department, College of Science, P.O. Box 36, Al-Khodh 123, Sultan Qaboos University (Oman)

    2006-03-15

    Nanosized iron-doped tin oxide solid solution was prepared by mixing tin oxide gel SnO{sub 2}.xH{sub 2}O with a boiling solution of iron nitrate. The XRD data of the as-prepared and annealed sample at 773 K show that the patterns are indexed to the rutile phase without any trace of an extra phase. SEM and TEM results performed on different selected area of the samples reveal a homogeneous composition of 8 at.% of Fe content and a size of about 2 nm of the particles. The particles size was found to increase slightly with temperature; about 7 nm after 24 h at 773 K. Structural and magnetic results seem to indicate that Fe{sup 3+} substitute for Sn{sup 4+} on the as-prepared sample. The system presents some weak ferromagnetic character at room temperature.

  20. Microjetting from a grooved Al surface under supported and unsupported shocks

    Science.gov (United States)

    Shao, Jian-Li; Wang, Pei; He, An-Min

    2014-08-01

    Using molecular dynamics methods, we simulate and compare the microjetting from a grooved Al surface induced by supported and unsupported shocks at different breakout pressures. Via the analysis on the microjetting morphologies and mass distributions, we find that the threshold of shock breakout pressure for the microjetting formation is almost same, but the variation of microjet mass with shock pressure shows a great difference for the two loading patterns. Under supported shock loading, the microjet mass keeps a continuous increase with increasing shock pressure, and release melting can enhance it markedly. By contrast, the microjet mass under unsupported shocks is smaller and seems no remarkable increase with shock pressure in our simulations (at extremely short pulses), implying the shock decaying can weaken the microjetting. Of course, a large area of fragments near the surface may form in this case. The microjet source distributions corresponding to supported and unsupported shocks are presented. It is found that the former becomes apparently broader than the latter with increasing shock pressure. Besides, the microjet tip velocity under supported shocks may appear a reduction because of the material strength effect below release melting. While under unsupported shocks, all the microjets in solid and melted states will experience the reduction of tip velocity. These decrements of tip velocity can be fitted by an exponential function.

  1. 14 CFR 29.475 - Tires and shock absorbers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tires and shock absorbers. 29.475 Section 29.475 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 29.475 Tires and shock absorbers. Unless otherwise...

  2. High pressure multiple shock response of aluminum

    International Nuclear Information System (INIS)

    Lawrence, R.J.; Asay, J.R.

    1977-01-01

    It is well known that both dynamic yield strength and rate-dependent material response exert direct influence on the development of surface and interface instabilities under conditions of strong shock loading. A detailed understanding of these phenomena is therefore an important aspect of the analysis of dynamic inertial confinement techniques which are being used in such applications as the generation of controlled thermonuclear fusion. In these types of applications the surfaces and interfaces under consideration can be subjected to cyclic loading characterized by shock pressures on the order of 100 GPa or more. It thus becomes important to understand how rate effects and material strength differ from the values observed in the low pressure regime where they are usually measured, as well as how they are altered by the loading history

  3. Shock initiation experiments on ratchet grown PBX 9502

    Energy Technology Data Exchange (ETDEWEB)

    Gustavsen, Richard L [Los Alamos National Laboratory; Thompson, Darla G [Los Alamos National Laboratory; Olinger, Barton W [Los Alamos National Laboratory; Deluca, Racci [Los Alamos National Laboratory; Bartram, Brian D [Los Alamos National Laboratory; Pierce, Timothy H [Los Alamos National Laboratory; Sanchez, Nathaniel J [Los Alamos National Laboratory

    2010-01-01

    This study compares the shock initiation behavior of PBX 9502 pressed to less than nominal density (nominal density is 1.890 {+-} 0.005 g/cm{sup 3}) with PBX 9502 pressed to nominal density and then ''ratchet grown'' to low density. PBX 9502 is an insensitive plastic bonded explosive consisting of 95 weight % dry-aminated tri-amino-tri-nitro-benzene (TATB) and 5 weight % Kel-F 800 plastic binder. ''Ratchet growth'' - an irreversible increase in specific volume - occurs when an explosive based on TATB is temperature cycled. The design of our study is as follows: PBX 9502, all from the same lot, received the following four treatments. Samples in the first group were pressed to less than nominal density. These were not ratchet grown and used as a baseline. Samples in the second group were pressed to nominal density and then ratchet grown by temperature cycling 30 times between -54 C and +80 C. Samples in the final group were pressed to nominal density and cut into 100 mm by 25.4 mm diameter cylinders. During thermal cycling the cylinders were axially constrained by a 100 psi load. Samples for shock initiation experiments were cut perpendicular (disks) and parallel (slabs) to the axial load. The four sample groups can be summarized with the terms pressed low, ratchet grown/no load, axial load/disks, and axial load/slabs. All samples were shock initiated with nearly identical inputs in plate impact experiments carried out on a gas gun. Wave profiles were measured after propagation through 3, 4, 5, and 6 mm of explosive. Side by side comparison of wave profiles from different samples is used as a measure of relative sensitivity. All reduced density samples were more shock sensitive than nominal density PBX 9502. Differences in shock sensitivity between ratchet grown and pressed to low density PBX 9502 were small, but the low density pressings are slightly more sensitive than the ratchet grown samples.

  4. Conversion electron Moessbauer spectroscopic studies on the chemical states of surface layers of corroded tin plates and tin-coated iron plates

    International Nuclear Information System (INIS)

    Kato, Akinori; Endo, Kazutoyo; Sano, Hirotoshi

    1980-01-01

    By means of the conversion electron Moessbauer spectroscopy (CEMS), we studied surface layers of ''tin'' plates and tin-coated iron plates corroded by various acids. Transmission Moessbauer spectra and X-ray diffraction patterns were also measured. Metastannic acid was formed, when the ''tin'' plate was corroded by nitric acid solution. In corrosion by phosphoric acid solution, the X-ray diffractometry revealed the formation of tin(IV) pyrophosphate. In corrosion by various organic acid solutions, the formation of oxides was identified by the 119 Sn CEMS, but not by the X-ray diffractometry because of the too thin corrosion layer. In corrosion of tin-coated iron plates, maleic acid, malonic acid, formic acid, and oxalic acid were used. It was determined by CEMS that the corrosion products caused by these acids were tin(IV) oxides, although they could not be identified by the X-ray diffractometry. CEMS also confirmed that the surface of uncorroded tin-coated iron plate was already oxidized by air. Colorimetric determinations of Sn and Fe dissolved from tin-coated iron plates to various acid solutions confirmed that maleic acid had the strongest corrosion effect among the organic acids studied. (author)

  5. 14 CFR 27.475 - Tires and shock absorbers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tires and shock absorbers. 27.475 Section 27.475 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 27.475 Tires and shock absorbers. Unless otherwise prescribed...

  6. Shock Absorbers Multi-Modeling and Suspension Optimization

    Directory of Open Access Journals (Sweden)

    LUPU Ciprian

    2013-05-01

    Full Text Available The standard dampers used by more 90% of vehicles have damping coefficients constant along stroke, so they can’t solve simultaneous all of them, situation solving practically using a relative dampingcoefficient able to made compromise between them. This paper design and simulation testing multi-models of two types of Damp (DSA and VZN. To compare the two types of suspension they are simulated in various road and load conditions. Analysis of simulation results is presente a new VZN shock absorber. This is an invention of the Institute of Mechanics of the Romanian Academy, and patented at European and U.S. [1], [2]. This is Called VZN shock absorber, iscoming from Variable Zeta Necessary acronym, for well moving in all road and load Conditions, Where zeta Represents the relative damping, Which is Adjusted automatically, stepwise, According to the piston positions [3,4,5]. Suspension systems are used in all air and ground transportation to protect that building transportation and cargo transported around against shocks and vibrations induced in the systemfrom the road Modifying damping coefficients (Zeta function piston position, being correlated with vehicle load and road unevenness.

  7. The Preparation and Property of Graphene /Tin Oxide Transparent Conductive Film

    Directory of Open Access Journals (Sweden)

    SUN Tao

    2017-02-01

    Full Text Available Graphene doped tin oxide composites were prepared with SnCIZ·2HZ 0 and graphene oxide as raw materials with sol-gel method and then spincoated on the quartz glass to manufacture a new transparent conductive film. The composite film was characterized with X-ray diffraction(XRDand scanning electron microscopy(SEM analysis. XRD results show that the graphene oxide was successfully prepared with Hummers method. The graphene layers and particulate SnOZ can be clearly observed in SEM photos. The transmittance and conductivity of the thin films were tested with ultraviolet visible spectrophotometer and Hall effect measurement. The results show that the transmittivity of composite film in visible region is more than 90% and surface square resistance is 41 S2/口.The graphene/ SnOZ film exhibits a higher performance in transparence and conductivity than commercial FTO glass.

  8. Shock Tube as an Impulsive Application Device

    Directory of Open Access Journals (Sweden)

    Soumya Ranjan Nanda

    2017-01-01

    Full Text Available Current investigations solely focus on application of an impulse facility in diverse area of high-speed aerodynamics and structural mechanics. Shock tube, the fundamental impulse facility, is specially designed and calibrated for present objectives. Force measurement experiments are performed on a hemispherical test model integrated with the stress wave force balance. Similar test model is considered for heat transfer measurements using coaxial thermocouple. Force and heat transfer experiments demonstrated that the strain gauge and thermocouple have lag time of 11.5 and 9 microseconds, respectively. Response time of these sensors in measuring the peak load is also measured successfully using shock tube facility. As an outcome, these sensors are found to be suitable for impulse testing. Lastly, the response of aluminum plates subjected to impulsive loading is analyzed by measuring the in-plane strain produced during deformation. Thus, possibility of forming tests in shock is also confirmed.

  9. Integration of regenerative shock absorber into vehicle electric system

    Science.gov (United States)

    Zhang, Chongxiao; Li, Peng; Xing, Shaoxu; Kim, Junyoung; Yu, Liangyao; Zuo, Lei

    2014-03-01

    Regenerative/Energy harvesting shock absorbers have a great potential to increase fuel efficiency and provide suspension damping simultaneously. In recent years there's intensive work on this topic, but most researches focus on electricity extraction from vibration and harvesting efficiency improvement. The integration of electricity generated from regenerative shock absorbers into vehicle electric system, which is very important to realize the fuel efficiency benefit, has not been investigated. This paper is to study and demonstrate the integration of regenerative shock absorber with vehicle alternator, battery and in-vehicle electrical load together. In the presented system, the shock absorber is excited by a shaker and it converts kinetic energy into electricity. The harvested electricity flows into a DC/DC converter which realizes two functions: controlling the shock absorber's damping and regulating the output voltage. The damping is tuned by controlling shock absorber's output current, which is also the input current of DC/DC converter. By adjusting the duty cycles of switches in the converter, its input impedance together with input current can be adjusted according to dynamic damping requirements. An automotive lead-acid battery is charged by the DC/DC converter's output. To simulate the working condition of combustion engine, an AC motor is used to drive a truck alternator, which also charges the battery. Power resistors are used as battery's electrical load to simulate in-vehicle electrical devices. Experimental results show that the proposed integration strategy can effectively utilize the harvested electricity and power consumption of the AC motor is decreased accordingly. This proves the combustion engine's load reduction and fuel efficiency improvement.

  10. Effect of thickness on optoelectrical properties of Nb-doped indium tin oxide thin films deposited by RF magnetron sputtering

    Science.gov (United States)

    Li, Shi-na; Ma, Rui-xin; Ma, Chun-hong; Li, Dong-ran; Xiao, Yu-qin; He, Liang-wei; Zhu, Hong-min

    2013-05-01

    Niobium-doped indium tin oxide (ITO:Nb) thin films are prepared on glass substrates with various film thicknesses by radio frequency (RF) magnetron sputtering from one piece of ceramic target material. The effects of thickness (60-360 nm) on the structural, electrical and optical properties of ITO: Nb films are investigated by means of X-ray diffraction (XRD), ultraviolet (UV)-visible spectroscopy, and electrical measurements. XRD patterns show the highly oriented (400) direction. The lowest resistivity of the films without any heat treatment is 3.1×10-4Ω·cm-1, and the resistivity decreases with the increase of substrate temperature. The highest Hall mobility and carrier concentration are 17.6 N·S and 1.36×1021 cm-3, respectively. Band gap energy of the films depends on substrate temperature, which varies from 3.48 eV to 3.62 eV.

  11. Embeddability behaviour of tin-based bearing material in dry sliding

    International Nuclear Information System (INIS)

    Zeren, Adalet

    2007-01-01

    In this study, tin-based bearing material has been investigated in dry sliding conditions. The low Sb content (7%) is known as SAE 12 and is Sn-Sb-Cu alloy and is widely used in the automotive industry. Wear and friction characteristics were determined with respect to sliding distance, sliding speed and bearing load, using a Tecquipment HFN type 5 journal bearing test equipment. Scanning electron microscopy (SEM) and energy-disperse X-ray spectrography (EDX) are used to understand the tribological events, especially embeddability. Thus, the purpose of this study is to investigate the tribological properties of tin-based bearing alloy used especially in heavy industrial service conditions. Tests were carried out in dry sliding conditions, since despite the presence of lubricant film, under heavy service conditions dry sliding may occur from time to time, causing local wear. As a result of local wear, bearing materials and bearing may be out of their tolerance limits in their early lifetime. Embeddability is an important property due to inversely affecting the hardness and the strength of the bearing

  12. Using a gel/plastic surrogate to study the biomechanical response of the head under air shock loading: a combined experimental and numerical investigation.

    Science.gov (United States)

    Zhu, Feng; Wagner, Christina; Dal Cengio Leonardi, Alessandra; Jin, Xin; Vandevord, Pamela; Chou, Clifford; Yang, King H; King, Albert I

    2012-03-01

    A combined experimental and numerical study was conducted to determine a method to elucidate the biomechanical response of a head surrogate physical model under air shock loading. In the physical experiments, a gel-filled egg-shaped skull/brain surrogate was exposed to blast overpressure in a shock tube environment, and static pressures within the shock tube and the surrogate were recorded throughout the event. A numerical model of the shock tube was developed using the Eulerian approach and validated against experimental data. An arbitrary Lagrangian-Eulerian (ALE) fluid-structure coupling algorithm was then utilized to simulate the interaction of the shock wave and the head surrogate. After model validation, a comprehensive series of parametric studies was carried out on the egg-shaped surrogate FE model to assess the effect of several key factors, such as the elastic modulus of the shell, bulk modulus of the core, head orientation, and internal sensor location, on pressure and strain responses. Results indicate that increasing the elastic modulus of the shell within the range simulated in this study led to considerable rise of the overpressures. Varying the bulk modulus of the core from 0.5 to 2.0 GPa, the overpressure had an increase of 7.2%. The curvature of the surface facing the shock wave significantly affected both the peak positive and negative pressures. Simulations of the head surrogate with the blunt end facing the advancing shock front had a higher pressure compared to the simulations with the pointed end facing the shock front. The influence of an opening (possibly mimicking anatomical apertures) on the peak pressures was evaluated using a surrogate head with a hole on the shell of the blunt end. It was revealed that the presence of the opening had little influence on the positive pressures but could affect the negative pressure evidently.

  13. Elastic-Plastic Behavior of U6Nb under Ramp Wave Loading

    International Nuclear Information System (INIS)

    Hayes, D. B.; Gray, G. T. III; Hixson, R. S.; Hall, C. A.

    2006-01-01

    When uranium-niobium (6 wt.%) alloy is shock loaded, the expected elastic precursor is absent. A prior model attributed this absence to shear-induced twinning and the concomitant shear stress reduction that prevented the shocked material from reaching the plastic yield point. In the present study, carefully prepared U6Nb was subjected to shock loading to verify the adequacy of the prior model. Other samples were loaded with a ramp pressure pulse with strain rate large enough so that significant twinning would not occur during the experiment. Backward integration analyses of these latter experiments' back surface motion give stress-strain loading paths in U6Nb that suggest ordinary elastic-plastic flow. Some of the U6Nb was pre-strained by cold rolling in an effort to further ensure that twinning did not affect wave propagation. Shock and ramp loadings yielded similar results to the baseline material except, as expected, they are consistent with a higher yield stress and twinning shear stress threshold

  14. Pressurized thermal shock evaluation of RPV-Stade

    International Nuclear Information System (INIS)

    Blauel, J.G.; Hodulak, L.; Siegele, D.; Nagel, G.; Hertlein, D.

    1997-01-01

    The presentation overviews the following issues: thermal shock analysis (thermohydraulics, temperatures and stresses, crack tip field parameters, cladding influence, methodology of fracture mechanics assessment); EOL safety evaluation for RPV Stade (initial conditions and input data, fracture toughness, load path diagrams, warm prestress effect, crack arrest, remaining load carrying capacity)

  15. Pressurized thermal shock evaluation of RPV-Stade

    Energy Technology Data Exchange (ETDEWEB)

    Blauel, J G; Hodulak, L; Siegele, D [Fraunhofer-Institut fuer Werkstoffmechanik, Freiburg im Breisgau (Germany); Nagel, G [PreussenElektra AG, Hannover (Germany); Hertlein, D [Siemens AG Unternehmensbereich KWU, Erlangen (Germany)

    1997-09-01

    The presentation overviews the following issues: thermal shock analysis (thermohydraulics, temperatures and stresses, crack tip field parameters, cladding influence, methodology of fracture mechanics assessment); EOL safety evaluation for RPV Stade (initial conditions and input data, fracture toughness, load path diagrams, warm prestress effect, crack arrest, remaining load carrying capacity).

  16. Directly smelted lead-tin alloys: A historical perspective

    Science.gov (United States)

    Dube, R. K.

    2010-08-01

    This paper discusses evidence related to the genesis and occurrence of mixed lead-tin ore deposit consisting of cassiterite and the secondary minerals formed from galena. These evidences belong to a very long time period ranging from pre-historic to as late as the nineteenth century a.d. This type of mixed ore deposits was smelted to prepare lead-tin alloys. The composition of the alloy depended on the composition of the starting ore mixture. A nineteenth century evidence for the production of directly smelted lead-tin alloys in southern Thailand is discussed. A unique and rather uncommon metallurgical terminology in Sanskrit language— Nāgaja—was introduced in India for the tin recovered from impure lead. This suggests that Indians developed a process for recovering tin from lead-tin alloys, which in all probability was based on the general principle of fire refining. It has been shown that in the context of India the possibility of connection between the word Nāgaja and the directly smelted lead-tin alloys cannot be ruled out.

  17. Effects of the shock duration on the response of CFRP composite laminates

    International Nuclear Information System (INIS)

    Gay, Elise; Berthe, Laurent; Boustie, Michel; Arrigoni, Michel; Buzaud, Eric

    2014-01-01

    Shock loads induce a local tensile stress within a sample. The location and amplitude of this high strain rate stress can be monitored respectively by the duration and intensity of the shock. The process is applied to carbon fibre reinforced polymer (CFRP) composites, involved in aeronautic or defense industry. This paper describes the response of CFRP laminates of different thicknesses to a shock load normal to the fibres direction. The effects of the shock duration on the wave propagation are key issues of this work. Experiments have been performed on high power laser facilities and on a high power pulsed generator to get a wide range of pulse duration from fs to µs. Numerical simulation provides a comprehensive approach of the wave propagation and tensile stress generation within these complex materials. The main result concerns the relation between the load duration, the tensile stress and the induced delamination within 1, 4 and 8 ply composite laminates. (paper)

  18. Toxicology of inorganic tin

    International Nuclear Information System (INIS)

    Burba, J.V.

    1982-01-01

    Tin(II) or stannous ion as a reducing agent is important in nuclear medicine because it is an essential component and common denominator for many in vivo radiodiagnostic agents, commonly called kits for the preparation of radiopharmaceuticals. This report is intended to alert nuclear medicine community regarding the wide range of biological effects that the stannous ion is capable of producing, and is a review of a large number of selected publications on the toxicological potential of tin(II)

  19. Thermal shock behavior of W-0.5 wt% Y{sub 2}O{sub 3} alloy prepared via a novel chemical method

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Mei-Ling [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Luo, Lai-Ma, E-mail: luolaima@126.com [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); National-Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009 (China); Lin, Jing-Shan [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Zan, Xiang; Zhu, Xiao-Yong [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); National-Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009 (China); Luo, Guang-Nan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Wu, Yu-Cheng, E-mail: ycwu@hfut.edu.cn [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); National-Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009 (China)

    2016-10-15

    A wet-chemical method combined with spark plasma sintering was used to prepare W-0.5 wt% Y{sub 2}O{sub 3} alloy. The W-0.5 wt% Y{sub 2}O{sub 3} precursor was reduced at 800 °C for 4 h under different hydrogen flow rates of 300, 400, 500, 600, and 700 ml/min. The reduced powder was analyzed by X-ray diffraction (XRD), laser particle size analyzer (LPSA), and scanning electron microscopy (SEM). An optimized process for reducing precursor was discussed. After sintering, the specimens were exposed to different laser beam irradiation energies (90, 120, 150, and 180 W) to simulate loads as expected for edge localized modes (ELMs). Top surface and cross-sectional morphology were observed by SEM, and the changes in hardness were evaluated. The changes in microstructural properties (i.e., Y{sub 2}O{sub 3}-particle distribution, crack propagation direction, depth of thermal shock effect, and grain size of the recrystallization region) after thermal shock were investigated.

  20. Simulation Study of Shock Reaction on Porous Material

    International Nuclear Information System (INIS)

    Xu Aiguo; Zhang Guangcai; Pan Xiaofei; Zhu Jianshi

    2009-01-01

    Direct modeling of porous materials under shock is a complex issue. We investigate such a system via the newly developed material-point method. The effects of shock strength and porosity size are the main concerns. For the same porosity, the effects of mean-void-size are checked. It is found that local turbulence mixing and volume dissipation are two important mechanisms for transformation of kinetic energy to heat. When the porosity is very small, the shocked portion may arrive at a dynamical steady state; the voids in the downstream portion reflect back rarefactive waves and result in slight oscillations of mean density and pressure; for the same value of porosity, a larger mean-void-size makes a higher mean temperature. When the porosity becomes large, hydrodynamic quantities vary with time during the whole shock-loading procedure: after the initial stage, the mean density and pressure decrease, but the temperature increases with a higher rate. The distributions of local density, pressure, temperature and particle-velocity are generally non-Gaussian and vary with time. The changing rates depend on the porosity value, mean-void-size and shock strength. The stronger the loaded shock, the stronger the porosity effects. This work provides a supplement to experiments for the very quick procedures and reveals more fundamental mechanisms in energy and momentum transportation. (general)

  1. A new apparatus to induce lysis of planktonic microbial cells by shock compression, cavitation and spray

    Science.gov (United States)

    Schiffer, A.; Gardner, M. N.; Lynn, R. H.; Tagarielli, V. L.

    2017-03-01

    Experiments were conducted on an aqueous growth medium containing cultures of Escherichia coli (E. coli) XL1-Blue, to investigate, in a single experiment, the effect of two types of dynamic mechanical loading on cellular integrity. A bespoke shock tube was used to subject separate portions of a planktonic bacterial culture to two different loading sequences: (i) shock compression followed by cavitation, and (ii) shock compression followed by spray. The apparatus allows the generation of an adjustable loading shock wave of magnitude up to 300 MPa in a sterile laboratory environment. Cultures of E. coli were tested with this apparatus and the spread-plate technique was used to measure the survivability after mechanical loading. The loading sequence (ii) gave higher mortality than (i), suggesting that the bacteria are more vulnerable to shear deformation and cavitation than to hydrostatic compression. We present the results of preliminary experiments and suggestions for further experimental work; we discuss the potential applications of this technique to sterilize large volumes of fluid samples.

  2. Shock disturbance of the I-Xe system

    International Nuclear Information System (INIS)

    Caffee, M.W.; Hohenberg, C.M.; Podosek, F.A.; Swindle, T.D.

    1982-01-01

    Three separate samples of the meteorite Bjurbole were artificially shocked at pressures of 70 kb, 200 kb, and 400 kb. Analysis of xenon released in stepwise heating shows that the I-Xe system of the 400 kb sample is substantially altered by the shock loading, and it is no longer possible to infer an age or trapped xenon composition for that sample. The 200-kb and 70-kb samples display isotopic structures progressively less altered demonstrating the gradations in shock disturbance likely to be found in natural systems. Interpretations of the I-Xe and Ar-40-Ar-39 systems for several naturally shocked meteorites are also presented. New data for Arapahoe do not confirm the previously reported age and trapped xenon composition, demonstrating instead that its I-Xe structure has been strongly disturbed by shock

  3. Characterization of tin selenides synthesized by high-energy milling

    Directory of Open Access Journals (Sweden)

    Marcela Achimovičová

    2011-12-01

    Full Text Available Tin selenides SnSeX (x=1,2 were synthesized from tin and selenium powder precursors by high-energy milling in the planetary ballmill Pulverisette 6 (Fritsch, Germany. The orthorhombic tin selenide SnSe and the hexagonal tin diselenide SnSe2 phases were formed after4 min and 5 min of milling, respectively. Specific surface area of both selenides increased with increasing time of mechanochemicalsynthesis. The particle size distribution analysis demonstrated that the synthesized products contain agglomerated selenide particlesconsisting of numerous idiomorphic tin selenide crystals, measuring from 2 to more than 100 nm in diameter, which were also documentedby TEM. UV-Vis spectrophotometry confirmed that tin selenide particles do not behave as quantum dots.

  4. Optically active polyurethane@indium tin oxide nanocomposite: Preparation, characterization and study of infrared emissivity

    International Nuclear Information System (INIS)

    Yang, Yong; Zhou, Yuming; Ge, Jianhua; Yang, Xiaoming

    2012-01-01

    Highlights: ► Silane coupling agent of KH550 was used to connect the ITO and polyurethanes. ► Infrared emissivity values of the hybrids were compared and analyzed. ► Interfacial synergistic action and orderly secondary structure were the key factors. -- Abstract: Optically active polyurethane@indium tin oxide and racemic polyurethane@indium tin oxide nanocomposites (LPU@ITO and RPU@ITO) were prepared by grafting the organics onto the surfaces of modified ITO nanoparticles. LPU@ITO and RPU@ITO composites based on the chiral and racemic tyrosine were characterized by FT-IR, UV–vis spectroscopy, X-ray diffraction (XRD), SEM, TEM, and thermogravimetric analysis (TGA), and the infrared emissivity values (8–14 μm) were investigated in addition. The results indicated that the polyurethanes had been successfully grafted onto the surfaces of ITO without destroying the crystalline structure. Both composites possessed the lower infrared emissivity values than the bare ITO nanoparticles, which indicated that the interfacial interaction had great effect on the infrared emissivity. Furthermore, LPU@ITO based on the optically active polyurethane had the virtue of regular secondary structure and more interfacial synergistic actions between organics and inorganics, thus it exhibited lower infrared emissivity value than RPU@ITO based on the racemic polyurethane.

  5. Empirical Model Development for Predicting Shock Response on Composite Materials Subjected to Pyroshock Loading. Volume 2, Part 1; Appendices

    Science.gov (United States)

    Gentz, Steven J.; Ordway, David O.; Parsons, David S.; Garrison, Craig M.; Rodgers, C. Steven; Collins, Brian W.

    2015-01-01

    The NASA Engineering and Safety Center (NESC) received a request to develop an analysis model based on both frequency response and wave propagation analyses for predicting shock response spectrum (SRS) on composite materials subjected to pyroshock loading. The model would account for near-field environment (approximately 9 inches from the source) dominated by direct wave propagation, mid-field environment (approximately 2 feet from the source) characterized by wave propagation and structural resonances, and far-field environment dominated by lower frequency bending waves in the structure. This document contains appendices to the Volume I report.

  6. Stress relaxation of shear in metals during shock loading

    International Nuclear Information System (INIS)

    Glazyrin, V.P.; Platova, T.M.

    1988-01-01

    Constructed determining equation, taking into account stress relaxation of shear, was used to calculate the evolution of plane shock waves of primary and secondary compression in metals. Values of shear stress and viscosity coefficient were

  7. Shock-induced modification of inorganic powders

    International Nuclear Information System (INIS)

    Graham, R.A.; Morosin, B.; Venturini, E.L.; Beauchamp, E.K.; Hammetter, W.F.

    1984-01-01

    The results of studies performed to quantify the characteristics of TiO2, ZrO2 and Si3N4 powders exposed to explosive loading and post-shock analysis are reported. The shocks were produced with plane wave generators and explosive pads impinging on steel disks, a copper recovery fixture, and then the samples. Peak pressures of 13 and 17 GPa were attained, along with 40 GPz at the center of the powder cavity. Data are provided on the changes occurring during the explosive densification and X-ray and paramagnetic studies of the products. Only fractured disks were obtained in the trials. The shock-treated materials were more free flowing than the original powders, which were fluffy. Post-shock annealing was a significant feature of the treated powders

  8. Preparation of textural lamellar tin deposits via electrodeposition

    Science.gov (United States)

    Wen, Xiaoyu; Pan, Xiaona; Wu, Libin; Li, Ruinan; Wang, Dan; Zhang, Jinqiu; Yang, Peixia

    2017-06-01

    Lamellar tin deposits were prepared by galvanostatical electroplating from the aqueous acidic-sulfate bath, with gelatin and benzalacetone dissolved in ethanol (ABA+EtOH) as additive, and their morphologies were investigated by scanning electron microscopy. Cathodic polarization curves revealed that the absorbability of ABA+EtOH on the cathode surface was higher than that of gelatin. X-ray diffraction analysis indicated preferred orientations of tin growth led to the formation of lamellar structure and distortion of tin lattice. The growth mechanism of lamellar tin was also discussed.

  9. Evaluation of surface characteristics under fretting of electrical contacts: Removal behaviour of hot dipped tin coating

    International Nuclear Information System (INIS)

    Park, Young Woo; Ramesh Bapu, G.N.K.; Lee, Kang Yong

    2009-01-01

    The fretting corrosion behaviour of hot dipped tin coating is investigated at low fretting cycles at ±25 μm displacement amplitude, 0.5N normal load, 3 Hz frequency, 45-50% relative humidity, and 25 ± 1 deg. C temperature. The typical characteristics of the change in contact resistance with fretting cycles are explained. The fretted surface is examined using laser scanning microscope, scanning electron microscope and energy dispersive X-ray analysis to assess the surface profile, extent of fretting damage, extent of oxidation and elemental distribution across the contact zone. The interdependence of extent of wear and oxidation increases the complexity of the fretting corrosion behaviour of tin coating. The variation of contact resistance clearly revealed the fretting of tin coating from 50 to 1200 cycles and the fretting of the substrate above 1200 cycles. The observed low and stable contact resistance region and the fluctuating resistance region at various fretting cycles are explained and substantiated with Scanning electron microscopy (SEM), laser scanning microscope (LSM) and energy dispersive analysis of X-rays (EDAX) analysis results of the fretted surface.

  10. Synthesis and properties of ternary mixture of nickel/cobalt/tin oxides for supercapacitors

    Science.gov (United States)

    Ferreira, C. S.; Passos, R. R.; Pocrifka, L. A.

    2014-12-01

    The present study reports the synthesis and morphological, structural and electrochemical characterization of ternary oxides mixture containing nickel, cobalt and tin. The ternary oxide is synthesized by Pechini method with subsequent deposition onto a titanium substrate in a thin-film form. XRD and EDS analysis confirm the formation of ternary film with amorphous nature. SEM analysis show that cracks on the film favor the gain of the surface area that is an interesting feature for electrochemical capacitors. The ternary film is investigated in KOH electrolyte solution using cyclic voltammetry and charge-discharge study with a specific capacitance of 328 F g-1, and a capacitance retention of 86% over 600 cycles. The values of specific power and specific energy was 345.7 W kg-1 and 18.92 Wh kg-1, respectively.

  11. Modeling and evaluation of HE driven shock effects in copper with the MTS model

    International Nuclear Information System (INIS)

    Murphy, M.J.; Lassila, D.F.

    1997-01-01

    Many experimental studies have investigated the effect of shock pressure on the post-shock mechanical properties of OFHC copper. These studies have shown that significant hardening occurs during shock loading due to dislocation processes and twinning. It has been demonstrated that when an appropriate initial value of the Mechanical Threshold Stress (MTS) is specified, the post-shock flow stress of OFE copper is well described by relationships derived independently for unshocked materials. In this study we consider the evolution of the MTS during HE driven shock loading processes and the effect on the subsequent flow stress of the copper. An increased post shock flow stress results in a higher material temperature due to an increase in the plastic work. An increase in temperature leads to thermal softening which reduces the flow stress. These coupled effects will determine if there is melting in a shaped charge jet or a necking instability in an EFP Ww. 'Me critical factor is the evolution path followed combined with the 'current' temperature, plastic strain, and strain rate. Preliminary studies indicate that in simulations of HE driven shock with very high resolution zoning, the MTS saturates because of the rate dependence in the evolution law. On going studies are addressing this and other issues with the goal of developing a version of the MT'S model that treats HE driven, shock loading, temperature, strain, and rate effects apriori

  12. Effect of the wave shocking treatment on the structure and strengthening of austenitic steels

    International Nuclear Information System (INIS)

    Blinov, V.M.; Chernogorova, O.P.; Drozdova, E.I.; Afanas'ev, I.A.

    2006-01-01

    The structure and hardening of austenitic manganese steels after shock wave treatment are studied. It is shown that the treatment results in the structure where an elementary cell size decreases with a pressure increase. The strain hardening resulted from shock wave loading can be estimated using a Hall-Petch equation. It is established that at similar degree of residual strains the shock wave loading compared to cold rolling gives rise to higher strengthening which value grows as austenite stacking fault energy decreases [ru

  13. Ultrafast Fiber Bragg Grating Interrogation for Sensing in Detonation and Shock Wave Experiments.

    Science.gov (United States)

    Rodriguez, George; Gilbertson, Steve M

    2017-01-27

    Chirped fiber Bragg grating (CFBG) sensors coupled to high speed interrogation systems are described as robust diagnostic approaches to monitoring shock wave and detonation front propagation tracking events for use in high energy density shock physics applications. Taking advantage of the linear distributed spatial encoding of the spectral band in single-mode CFBGs, embedded fiber systems and associated photonic interrogation methodologies are shown as an effective approach to sensing shock and detonation-driven loading processes along the CFBG length. Two approaches, one that detects spectral changes in the integrated spectrum of the CFBG and another coherent pulse interrogation approach that fully resolves its spectral response, shows that 100-MHz-1-GHz interrogation rates are possible with spatial resolution along the CFBG in the 50 µm to sub-millimeter range depending on the combination of CFBG parameters (i.e., length, chirp rate, spectrum) and interrogator design specifics. Results from several dynamic tests are used to demonstrate the performance of these high speed systems for shock and detonation propagation tracking under strong and weak shock pressure loading: (1) linear detonation front tracking in the plastic bonded explosive (PBX) PBX-9501; (2) tracking of radial decaying shock with crossover to non-destructive CFBG response; (3) shock wave tracking along an aluminum cylinder wall under weak loading accompanied by dynamic strain effects in the CFBG sensor.

  14. Shock loading and reactive flow modeling studies of void induced AP/AL/HTPB propellant

    Science.gov (United States)

    Miller, P. J.; Lindfors, A. J.

    1998-07-01

    The unreactive Hugoniot of a class 1.3 propellant has been investigated by shock compression experiments. The results are analyzed in terms of an ignition and growth reactive flow model using the DYNA2D hydrocode. The calculated shock ignition parameters of the model show a linear dependence on measured void volume which appears to reproduce the observed gauge records well. Shock waves were generated by impact in a 75 mm single stage powder gun. Manganin and PVDF pressure gauges provided pressure-time histories to 140 kbar. The propellants were of similar formulation differing only in AP particle size and the addition of a burn rate modifer (Fe2O3) from that of previous investigations. Results show neglible effect of AP particle size on shock response in contrast to the addition of Fe2O3 which appears to `stiffen' the unreactive Hugoniot and enhances significantly the reactive rates under shock. The unreactive Hugoniot, within experimental error, compares favorably to the solid AP Hugoniot. Shock experiments were performed on propellant samples strained to induce insitu voids. The material state was quantified by uniaxial tension dialatometry. The experimental records show a direct correlation between void volume (0 to 1.7%) and chemical reactivity behind the shock front. These results are discussed in terms of `hot spot' ignition resulting from the shock collapse of the voids.

  15. Hybrid composite thin films composed of tin oxide nanoparticles and cellulose

    International Nuclear Information System (INIS)

    Mahadeva, Suresha K; Nayak, Jyoti; Kim, Jaehwan

    2013-01-01

    This paper reports the preparation and characterization of hybrid thin films consisting of tin oxide (SnO 2 ) nanoparticles and cellulose. SnO 2 nanoparticle loaded cellulose hybrid thin films were fabricated by a solution blending technique, using sodium dodecyl sulfate as a dispersion agent. Scanning and transmission electron microscopy studies revealed uniform dispersion of the SnO 2 nanoparticles in the cellulose matrix. Reduction in the crystalline melting transition temperature and tensile properties of cellulose was observed due to the SnO 2 nanoparticle loading. Potential application of these hybrid thin films as low cost, flexible and biodegradable humidity sensors is examined in terms of the change in electrical resistivity of the material exposed to a wide range of humidity as well as its response–recovery behavior. (paper)

  16. Effects of laser shock processing on mechanical properties and micro-structure of ANSI 304 austenitic stainless steel

    International Nuclear Information System (INIS)

    Luo, K.Y.; Lu, J.Z.; Zhang, Y.K.; Zhou, J.Z.; Zhang, L.F.; Dai, F.Z.; Zhang, L.; Zhong, J.W.; Cui, C.Y.

    2011-01-01

    Highlights: → Effects of LSP on mechanical properties of stainless steel ANSI 304 are evaluated. → LSP can clearly enhance the values of mechanical properties in the shocked region. → Martensite transformation does not take place in the surface layer subjected to LSP. → Enhancement mechanisms of LSP on mechanical property of stainless steel are revealed. → The results can provide some insights on the surface modification of stainless steel. - Abstract: The aim of this article is to address the effects of a single laser shock processing (LSP) impact on the nano-hardness, elastic modulus, residual stress and phase transformation of ANSI 304 austenitic stainless steel. Residual stress distribution of the LSP-shocked region is determined by X-ray diffraction (XRD) with sin 2 ψ method, and the micro-structural features in the near-surface layer are characterized by using cross-sectional optical microscopy (OM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). By comparing with the untreated samples, LSP can clearly improve nano-hardness, elastic modulus, and residual stress in the LSP-shocked region. The underlying enhancement mechanisms of LSP on nano-hardness, elastic modulus and residual stress of stainless steel ANSI 304 are also revealed. These studies may provide some important insights into surface modification for metal materials.

  17. IMPEDANCE SPECTROSCOPY OF POLYCRYSTALLINE TIN DIOXIDE FILMS

    Directory of Open Access Journals (Sweden)

    D. V. Adamchuck

    2016-01-01

    Full Text Available The aim of this work is the analysis of the influence of annealing in an inert atmosphere on the electrical properties and structure of non-stoichiometric tin dioxide films by means of impedance spectroscopy method. Non-stoichiometric tin dioxide films were fabricated by two-step oxidation of metallic tin deposited on the polycrystalline Al2O3 substrates by DC magnetron sputtering. In order to modify the structure and stoichiometric composition, the films were subjected to the high temperature annealing in argon atmosphere in temperature range 300–800 °С. AC-conductivity measurements of the films in the frequency range 20 Hz – 2 MHz were carried out. Variation in the frequency dependencies of the real and imaginary parts of the impedance of tin dioxide films was found to occur as a result of high-temperature annealing. Equivalent circuits for describing the properties of films with various structure and stoichiometric composition were proposed. Possibility of conductivity variation of the polycrystalline tin dioxide films as a result of аnnealing in an inert atmosphere was demonstrated by utilizing impedance spectroscopy. Annealing induces the recrystallization of the films, changing in their stoichiometry as well as increase of the sizes of SnO2 crystallites. Variation of electrical conductivity and structure of tin dioxide films as a result of annealing in inert atmosphere was confirmed by X-ray diffraction analysis. Analysis of the impedance diagrams of tin dioxide films was found to be a powerful tool to study their electrical properties. 

  18. Surface Modification of Indium Tin Oxide Nanoparticles to Improve Its Distribution in Epoxy-Silica Polymer Matrix

    Directory of Open Access Journals (Sweden)

    Mostafa Jafari

    2014-10-01

    Full Text Available A semiconducting nanoparticle indium tin oxide (ITO was modified with silane groups and for this purpose trimethoxysilane (TMOS precursor was used under specific experimental conditions for surface modification of ITO nanoparticles. It is found that the modification of ITO nanoparticles increases the interactions between the filler and the matrix and subsequently improves the distibution of indium tin oxide nanoparticles in the polymer matrix. The epoxisilica polymer matrix was produced using trimethoxysilane and 3-glycidyloxypropyl trimethoxysilane precursors and ethylenediamine (EDA as curing agent at low temperature by sol-gel process. The sol-gel process was very useful due to its easily controllable process, solution concentration and homogeneity without using expensive and complicated equipments in comparison with other methods. Then, Fourier transform infrared (FTIR spectroscopy was employed to study the formation of Si-O-Si and Si-OH groups on ITO nanoparticles. X-Ray diffraction (XRD technique and thermal gravimetric analysis (TGA were employed to investigate the modification and weight loss of the modified ITO, respectively, as an indication of the presence of organic groups on these nanoparticles. The separation analyzer tests were performed to check the stability of the nanoparticles suspension and it revealed that due to better interaction of nanoparticles with the polymer matrix the stability of modified ITO suspention is higher than the unmodified sample. The morphology and particle distribution were determined by scanning electron microscopy (SEM. It was found that the distibution of modified indium tin oxide in epoxy-silica polymer matrix was improved in comparison with pure ITO.

  19. Mitigating tin whisker risks theory and practice

    CERN Document Server

    Handwerker, Carol A; Bath, Jasbir

    2016-01-01

    Discusses the growth mechanisms of tin whiskers and the effective mitigation strategies necessary to reduce whisker growth risks. This book covers key tin whisker topics, ranging from fundamental science to practical mitigation strategies. The text begins with a review of the characteristic properties of local microstructures around whisker and hillock grains to identify why these particular grains and locations become predisposed to forming whiskers and hillocks. The book discusses the basic properties of tin-based alloy finishes and the effects of various alloying elements on whisker formation, with a focus on potential mechanisms for whisker suppression or enhancement for each element. Tin whisker risk mitigation strategies for each tier of the supply chain for high reliability electronic systems are also described.

  20. Anomalous mass transport in Au/304 stainless steel powder under shock loading

    Energy Technology Data Exchange (ETDEWEB)

    Staudhammer, Karl P.

    2004-01-01

    Dynamic deformation experiments on gold plated 304L stainless steel powders were undertaken using a axial symmetrical implosion geometry. These experiments utilized pressures of 0.08 to 1.0 Mbar and contained a symmetric radial melt region along the central axis of the sample holder. To understand the role of deformation in a porous material, the pressure, and temperature as well as the deformation heat and associated defects must be accounted for. Using a strain controllable shock loading design it was possible to separate and control independently strain and pressure. Thus enabling the ability to control the added heat from the deformation process undergoing compaction/consolidation of the powder. When the added heat of consolidation deformation exceeds the melt temperature of the 304 powders, a melt zone results that can consume large regions of the compact. It is within these regions that very high diffusion of gold into the powder occurs. These anomalous increases have been observed via optical microscopy, scanning electron microscopy and EDAX measurements. Values exceeding 1200 m/sec have been measured and correlated to the powder sizes, size distribution and packing density, concomitant with sample container strains ranging from 2.0% to 26%.

  1. A comparative study on shock compression of nanocrystalline Al and Cu: Shock profiles and microscopic views of plasticity

    International Nuclear Information System (INIS)

    Ma, Wen; Hou, Yong; Zhu, Wenjun

    2013-01-01

    Shock compressions of nanocrystalline (nc) metals Al and Cu with the same grain size and texture are studied by using molecular dynamics simulations. Results have revealed that the shock front of both Al and Cu can be divided into three stages: elastic, grain-boundary-mediated, and dislocation-mediated plastic deformation. The transition planes among these three stages are proven to be non-planar by two-dimensional shock response analysis, including local stress, shear, temperature, and atom configuration. The difference between shocked Al and Cu is that the rise rate of the elastic stage of Cu is slightly higher than that of Al, and that the shock-front width of Al is wider than Cu at the same loading conditions. For the plastic stage, the dislocation density of shocked Al is lower than Cu, and the contribution of grain-boundary-mediated plasticity to shock front and strain for nc Al is more pronounced than for nc Cu. These results are explained through intrinsic material properties and atomistic analysis of the plastic process. In the case of the shocked Al sample, partial dislocations, perfect dislocations, and twins are observed, but few evidence of perfect dislocations and twins are observed in the shocked Cu

  2. Thermal shock behaviour of different tungsten grades under varying conditions

    Energy Technology Data Exchange (ETDEWEB)

    Wirtz, Oliver Marius

    2012-07-19

    Thermonuclear fusion power plants are a promising option to ensure the energy supply for future generations, but in many fields of research enormous challenges have to be faced. A major step on the way to the prototype fusion reactor DEMO will be ITER which is build in Cadarache, southern France. One of the most critical issues is the field of in-vessel materials and components, in particular the plasma facing materials (PFM). PFMs that will be used in a device like ITER have to withstand severe environmental conditions in terms of steady state and transient thermal loads as well as high particle fluxes such as hydrogen, helium and neutrons. Candidate wall materials are beryllium, tungsten and carbon based materials like CFC (carbon fibre composite). Tungsten is the most promising material for an application in the divertor region with very severe loading conditions and it will most probably also be used as PFM for DEMO. Hence, this work focuses on the investigation of the thermal shock response of different tungsten grades in order to understand the damage mechanisms and to identify material parameters which influence this behaviour under ITER and DEMO relevant operation conditions. Therefore the microstructure and the mechanical and thermal properties of five industrially manufactured tungsten grades were characterised. All five tungsten grades were exposed to transient thermal events with very high power densities of up to 1.27 GWm{sup -2} at varying base temperatures between RT and 600 C in the electron beam device JUDITH 1. The pulse numbers were limited to a maximum of 1000 in order to avoid immoderate workload on the test facility and to have enough time to cover a wide range of loading conditions. The results of this damage mapping enable to define different damage and cracking thresholds for the investigated tungsten grades and to identify certain material parameters which influence the location of these thresholds and the distinction of the induced

  3. Thermal shock behaviour of different tungsten grades under varying conditions

    International Nuclear Information System (INIS)

    Wirtz, Oliver Marius

    2012-01-01

    Thermonuclear fusion power plants are a promising option to ensure the energy supply for future generations, but in many fields of research enormous challenges have to be faced. A major step on the way to the prototype fusion reactor DEMO will be ITER which is build in Cadarache, southern France. One of the most critical issues is the field of in-vessel materials and components, in particular the plasma facing materials (PFM). PFMs that will be used in a device like ITER have to withstand severe environmental conditions in terms of steady state and transient thermal loads as well as high particle fluxes such as hydrogen, helium and neutrons. Candidate wall materials are beryllium, tungsten and carbon based materials like CFC (carbon fibre composite). Tungsten is the most promising material for an application in the divertor region with very severe loading conditions and it will most probably also be used as PFM for DEMO. Hence, this work focuses on the investigation of the thermal shock response of different tungsten grades in order to understand the damage mechanisms and to identify material parameters which influence this behaviour under ITER and DEMO relevant operation conditions. Therefore the microstructure and the mechanical and thermal properties of five industrially manufactured tungsten grades were characterised. All five tungsten grades were exposed to transient thermal events with very high power densities of up to 1.27 GWm -2 at varying base temperatures between RT and 600 C in the electron beam device JUDITH 1. The pulse numbers were limited to a maximum of 1000 in order to avoid immoderate workload on the test facility and to have enough time to cover a wide range of loading conditions. The results of this damage mapping enable to define different damage and cracking thresholds for the investigated tungsten grades and to identify certain material parameters which influence the location of these thresholds and the distinction of the induced damages

  4. Tin (II Chloride Catalyzed Esterification of High FFA Jatropha Oil: Experimental and Kinetics Study

    Directory of Open Access Journals (Sweden)

    Ratna Dewi Kusumaningtyas

    2014-05-01

    Full Text Available Biodiesel is one of the promising energy source alternatives to fossil fuel. To produce biodiesel in a more economical way, the employment of the low-cost feed stocks, such as non-edible oils with high free fatty acid (FFA, is necessary. Accordingly, the esterification reaction of FFA in vegetable oils plays an important role in the biodiesel production. In this work, esterification of FFA contained in Crude Jatropha Oil (CJO in the presence of tin (II chloride catalyst in a batch reactor has been carried out. The esterification reaction was conducted using methanol at the temperature of 40-60 °C for 4 hours. The effect of molar ratio of methanol to oil was studied in the range 15:1 to 120:1. The influence of catalyst loading was investigated in the range of 2.5 to 15% w/w oil. The optimum reaction conversion was obtained at 60 °C with the catalyst loading of 10% w/w oil and molar ratio of methanol to oil of 120:1. A pseudo-homogeneous reversible second order kinetic model for describing the esterification of FFA contained in CJO with methanol over tin (II chloride catalyst was developed based on the experimental data. The kinetic model can fit the data very well.

  5. Observations of Tin/Water Thermal Explosions in a Long-Tube Geometry. Their Interpretation and Consequences for the Detonation Model

    International Nuclear Information System (INIS)

    Hall, R.W.; Board, S.J.; Baines, M.

    1979-01-01

    This paper presents details of experiments designed to test the detonation model of thermal explosions (Board et al, 1975); on this theory large-scale explosions should propagate steadily at supersonic velocities through a fuel coolant mixture, giving a yield which has been shown to depend on details of the fragmentation and heat transfer behind the shock front. Observations of propagating explosions have been reported previously. In the present work, a long-tube geometry is used since in 1D, propagation measurements are particularly easy to interpret. Also, in 2D and 3D geometries radial flow can tend to extinguish shock waves and if a single-phase region of coolant is present, pressure pulses can propagate ahead of the two-phase shock in the intermixed region. This paper describes the six experiments that all use molten tin and water mixtures. In the first four, detailed pressure measurement was the main objective; the last two are attempts at flow visualization to aid the interpretation of these. The results obtained and the implications for the detonation model are discussed. A detailed interpretation in terms of fragmentation and heat transfer processes behind the shock is attempted. The implications of the work for reactor materials are then briefly outlined

  6. 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

  7. Yield strength measurement of shock-loaded metal by flyer-impact perturbation method

    Science.gov (United States)

    Ma, Xiaojuan; Shi, Zhan

    2018-06-01

    Yield strength is one of the most important physical properties of a solid material, especially far from its melting line. The flyer-impact perturbation method measures material yield strength on the basis of correlation between the yield strength under shock compression and the damping of oscillatory perturbations in the shape of a shock front passing through the material. We used flyer-impact experiments on targets with machined grooves on the impact surface of shock 6061-T6 aluminum to between 32 and 61 GPa and recorded the evolution of the shock front perturbation amplitude in the sample with electric pins. Simulations using the elastic-plastic model can be matched to the experiments, explaining well the form of the perturbation decay and constraining the yield strength of 6061-T6 aluminum to be 1.31-1.75 GPa. These results are in agreement with values obtained from reshock and release wave profiles. We conclude that the flyer-impact perturbation method is indeed a new means to measure material strength.

  8. High shock load testing of lithium-thionyl chloride batteries

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, J.; Marincic, N.

    1983-10-01

    Low rate cylindrical cells have been developed, capable of withstanding mechanical shocks up to 23,000 g's for one millisecond. The cells were based on the lithium-thionyl chloride battery system and totally hermetic stainless steel hardware incorporating a glass sealed positive terminal. Four cells in series were required to deliver 25 mA pulses at a minimum voltage of 10 V before and after such exposure to one mechanical shock. Batteries were contained in a hardened steel housing and mounted within a projectile accelerated by means of a gas gun. The velocity of the projectile was measured with electronic probes immediately before impact and the deceleration was effected using a special aluminum honeycomb structure from which the g values were calculated. A high survival rate for the cells was achieved in spite of some mechanical damage to the battery housing still present.

  9. NMR studies of metallic tin confined within porous matrices

    International Nuclear Information System (INIS)

    Charnaya, E. V.; Tien, Cheng; Lee, M. K.; Kumzerov, Yu. A.

    2007-01-01

    119 Sn NMR studies were carried out for metallic tin confined within synthetic opal and porous glass. Tin was embedded into nanoporous matrices in the melted state under pressure. The Knight shift for liquid confined tin was found to decrease with decreasing pore size. Correlations between NMR line shapes, Knight shift, and pore filling were observed. The melting and freezing phase transitions of tin under confinement were studied through temperature dependences of NMR signals upon warming and cooling. Melting of tin within the opal matrix agreed well with the liquid skin model suggested for small isolated particles. The influence of the pore filling on the melting process was shown

  10. Evaluation of Nd-Loaded SnO2:F Films Coated via Spray Pyrolysis

    Science.gov (United States)

    Turgut, G.

    2018-07-01

    Thin layers of single (F)- and double (F/Nd)-incorporated tin oxide have been coated on glass substrate via spray pyrolysis. The structural, morphological, electrical, and optical features of F-incorporated samples were evaluated depending on the Nd loading. X-ray diffraction analysis revealed that samples had tetragonal tin oxide structure with (211) and (200) preferential directions. The crystallite size and strain values varied from 37.98 nm and 1.21 × 10-3 to 52.12 nm and 1.88 × 10-3. Scanning electron microscopy analysis showed that the samples consisted of pyramidal, polyhedral, and needle-shaped granules. The lowest sheet resistance value of 1.22 Ω was found for 1.8 at.% Nd + 25 at.% F-coloaded SnO2. However, the widest optical bandgap of 4.01 eV was observed for the single 25 at.% F-loaded sample. The Urbach tail and figure of merit also changed in the ranges of 664 meV to 1296 meV and 6.4 × 10-2 Ω-1 to 2.3 × 10-3 Ω-1, respectively. The results presented herein indicate that the character of F-doped tin oxide films can be controlled by Nd loading and that these films could be useful for technological applications.

  11. Strategies to Reduce Tin and Other Metals in Electronic Cigarette Aerosol.

    Directory of Open Access Journals (Sweden)

    Monique Williams

    Full Text Available Metals are present in electronic cigarette (EC fluid and aerosol and may present health risks to users.The objective of this study was to measure the amounts of tin, copper, zinc, silver, nickel and chromium in the aerosol from four brands of EC and to identify the sources of these metals by examining the elemental composition of the atomizer components.Four brands of popular EC were dissected and the cartomizers were examined microscopically. Elemental composition of cartomizer components was determined using integrated energy dispersive X-ray microanalysis, and the concentrations of the tin, copper, zinc silver, nickel, and chromium in the aerosol were determined for each brand using inductively coupled plasma optical emission spectroscopy.All filaments were made of nickel and chromium. Thick wires were copper coated with either tin or silver. Wires were joined to each other by tin solder, brazing, or by brass clamps. High concentrations of tin were detected in the aerosol when tin solder joints were friable. Tin coating on copper wires also contributed to tin in the aerosol.Tin concentrations in EC aerosols varied both within and between brands. Tin in aerosol was reduced by coating the thick wire with silver rather than tin, placing stable tin solder joints outside the atomizing chamber, joining wires with brass clamps or by brazing rather than soldering wires. These data demonstrate the feasibility of removing tin and other unwanted metals from EC aerosol by altering designs and using materials of suitable quality.

  12. Effect of Graphene Addition on Mechanical Properties of TiN

    International Nuclear Information System (INIS)

    Shon, In-Jin; Yoon, Jin-Kook; Hong, Kyung-Tae

    2017-01-01

    Despite of many attractive properties of TiN, the current concern about the TiN focuses on its low fracture toughness below the ductile-brittle transition temperature. To improve its mechanical properties, the approach generally utilized has been the addition of a second phase to form composites and to make nanostructured materials. In this respect, highly dense nanostructured TiN and TiN-graphene composites were obtained within two min at 1250 ℃. The grain size of TiN was reduced remarkably by the addition of graphene. The addition of graphene to TiN simultaneously improved the fracture toughness and hardness of TiN-graphene composite due to refinement of TiN and deterring crack propagation by graphene. This study demonstrates that the graphene can be an effective reinforcing agent for improved hardness and fracture toughness of TiN composites.

  13. Effect of Graphene Addition on Mechanical Properties of TiN

    Energy Technology Data Exchange (ETDEWEB)

    Shon, In-Jin [Chonbuk National University, Jeonju (Korea, Republic of); Yoon, Jin-Kook; Hong, Kyung-Tae [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2017-03-15

    Despite of many attractive properties of TiN, the current concern about the TiN focuses on its low fracture toughness below the ductile-brittle transition temperature. To improve its mechanical properties, the approach generally utilized has been the addition of a second phase to form composites and to make nanostructured materials. In this respect, highly dense nanostructured TiN and TiN-graphene composites were obtained within two min at 1250 ℃. The grain size of TiN was reduced remarkably by the addition of graphene. The addition of graphene to TiN simultaneously improved the fracture toughness and hardness of TiN-graphene composite due to refinement of TiN and deterring crack propagation by graphene. This study demonstrates that the graphene can be an effective reinforcing agent for improved hardness and fracture toughness of TiN composites.

  14. Dynamic testing of adhesive joints using a shock testing machine

    NARCIS (Netherlands)

    Aanhold, J.E. van; Weersink, A.F.J.; Ludolphy, J.W.L.

    1998-01-01

    A light-weight shock testing machine, designed for type approval testing of naval equipment up to 300 kg mass, has been modified into a dynamic tensile test rig. This enables to test structural details for high rate dynamic tensile loadings such as occur during underwater shock. The maximum capacity

  15. Microwave plasma CVD of NANO structured tin/carbon composites

    Science.gov (United States)

    Marcinek, Marek [Warszawa, PL; Kostecki, Robert [Lafayette, CA

    2012-07-17

    A method for forming a graphitic tin-carbon composite at low temperatures is described. The method involves using microwave radiation to produce a neutral gas plasma in a reactor cell. At least one organo tin precursor material in the reactor cell forms a tin-carbon film on a supporting substrate disposed in the cell under influence of the plasma. The three dimensional carbon matrix material with embedded tin nanoparticles can be used as an electrode in lithium-ion batteries.

  16. Transonic Shock-Wave/Boundary-Layer Interactions on an Oscillating Airfoil

    Science.gov (United States)

    Davis, Sanford S.; Malcolm, Gerald N.

    1980-01-01

    Unsteady aerodynamic loads were measured on an oscillating NACA 64A010 airfoil In the NASA Ames 11 by 11 ft Transonic Wind Tunnel. Data are presented to show the effect of the unsteady shock-wave/boundary-layer interaction on the fundamental frequency lift, moment, and pressure distributions. The data show that weak shock waves induce an unsteady pressure distribution that can be predicted quite well, while stronger shock waves cause complex frequency-dependent distributions due to flow separation. An experimental test of the principles of linearity and superposition showed that they hold for weak shock waves while flows with stronger shock waves cannot be superimposed.

  17. Model for calculating shock loading and release paths for multicomponent geologic media

    International Nuclear Information System (INIS)

    Butkovich, T.R.; Moran, B.; Burton, D.E.

    1981-07-01

    A model has been devised to calculate shock Hugoniots and release paths off the Hugoniots for multicomponent rocks containing silicate, carbonate, and water. Hugoniot equations of state are constructed from relatively simple measurements of rock properties including bulk density, grain density of the silicate component, and weight fractions of water and carbonate. Release paths off the composite Hugoniot are calculated by mixing release paths off the component Hugoniots according to their weight fractions. If the shock imparts sufficient energy to the component to cause vaporization, a gas equation of state is used to calculate the release paths. For less energetic shocks, the rock component will unload like a solid or liquid, taking into account the irreversible removal of air-filled porosity

  18. Strategies to Reduce Tin and Other Metals in Electronic Cigarette Aerosol

    Science.gov (United States)

    Williams, Monique; To, An; Bozhilov, Krassimir; Talbot, Prue

    2015-01-01

    Background Metals are present in electronic cigarette (EC) fluid and aerosol and may present health risks to users. Objective The objective of this study was to measure the amounts of tin, copper, zinc, silver, nickel and chromium in the aerosol from four brands of EC and to identify the sources of these metals by examining the elemental composition of the atomizer components. Methods Four brands of popular EC were dissected and the cartomizers were examined microscopically. Elemental composition of cartomizer components was determined using integrated energy dispersive X-ray microanalysis, and the concentrations of the tin, copper, zinc silver, nickel, and chromium in the aerosol were determined for each brand using inductively coupled plasma optical emission spectroscopy. Results All filaments were made of nickel and chromium. Thick wires were copper coated with either tin or silver. Wires were joined to each other by tin solder, brazing, or by brass clamps. High concentrations of tin were detected in the aerosol when tin solder joints were friable. Tin coating on copper wires also contributed to tin in the aerosol. Conclusions Tin concentrations in EC aerosols varied both within and between brands. Tin in aerosol was reduced by coating the thick wire with silver rather than tin, placing stable tin solder joints outside the atomizing chamber, joining wires with brass clamps or by brazing rather than soldering wires. These data demonstrate the feasibility of removing tin and other unwanted metals from EC aerosol by altering designs and using materials of suitable quality. PMID:26406602

  19. Molten fuel/coolant interaction studies: some results obtained with the Windscale small shock tube rig

    International Nuclear Information System (INIS)

    Higham, E.J.; Vaughan, G.J.

    1978-02-01

    Experiments are described in which water has been brought into contact with various molten metals in a shock tube, thus simulating the fall of coolant into molten uranium dioxide in a postulated reactor accident. Impact velocities of the water on to the molten material were in the range 5 to 7 m/s. Shock-pulse pressures in the water column after impact and particle size distributions of the dispersed resolidified material that was recovered were measured. The proportion of dispersed material and the size of the shock pulse (by comparison with that expected from water hammer alone) have been used as criteria for the occurrence of a molten fuel/coolant interaction and such interactions of varying degrees of violence have been found for water/aluminium, water/bismuth, water/tin, over a range of temperatures from 350 0 C to 950 0 C, for water/boric oxide, but not for water/magnesium. (author)

  20. Shock-induced electrical activity in polymeric solids. A mechanically induced bond scission model

    International Nuclear Information System (INIS)

    Graham, R.A.

    1979-01-01

    When polymeric solids are subjected to high-pressure shock loading, two anomalous electrical phenomena, shock-induced conduction and shock-induced polarization, are observed. The present paper proposes a model of mechanically induced bond scission within the shock front to account for the effects. An experimental study of shock-induced polarization in poly(pyromellitimide) (Vespel SP-1) is reported for shock compressions from 17 to 23% (pressures from 2.5 to 5.4 GPa). Poly(pyromellitimide) is found to be a strong generator of such polarization and the polarization is found to reflect an irreversible or highly hysteretic process. The present measurements are combined with prior measurements to establish a correlation between monomer structure and strength of shock-induced polarization; feeble signals are observed in the simpler monomer repeat units of poly(tetrafluoroethylene) and polyethylene while the strongest signals are observed in more complex monomers of poly(methyl methacrylate) and poly(pyromellitimide). It is also noted that there is an apparent correlation between shock-induced conduction and shock-induced polarization. Such shock-induced electrical activity is also found to be well correlated with the propensity for mechanical bond scission observed in experiments carried out in conventional mechanochemical studies. The bond scission model can account for characteristics observed for electrical activity in shock-loaded polymers and their correlation to monomer structure. Localization of elastic energy within the monomer repeat unit or along the main chain leads to the different propensities for bond scission and resulting shock-induced electrical activity

  1. Diffuse scattering in metallic tin polymorphs

    International Nuclear Information System (INIS)

    Wehinger, Björn; Bosak, Alexeï; Piccolboni, Giuseppe; Krisch, Michael; Refson, Keith; Chernyshov, Dmitry; Ivanov, Alexandre; Rumiantsev, Alexander

    2014-01-01

    The lattice dynamics of the metallic tin β and γ polymorphs has been studied by a combination of diffuse scattering, inelastic x-ray scattering and density functional perturbation theory. The non-symmorphic space group of the β -tin structure results in unusual asymmetry of thermal diffuse scattering. Strong resemblance of the diffuse scattering intensity distribution in β and γ-tin were observed, reflecting the structural relationship between the two phases and revealing the qualitative similarity of the underlying electronic potential. The strong influence of the electron subsystem on inter-ionic interactions creates anomalies in the phonon dispersion relations. All observed features are described in great detail by the density functional perturbation theory for both β - and γ-tin at arbitrary momentum transfers. The combined approach delivers thus a complete picture of the lattice dynamics in harmonic description. (paper)

  2. Gas Sensing of Fluorine Doped Tin Oxide Thin Films Prepared by Spray Pyrolysis

    Directory of Open Access Journals (Sweden)

    A. A. YADAV

    2008-05-01

    Full Text Available Fluorine doped tin oxide (F: SnO2 films have been prepared onto the amorphous glass substrates by a spray pyrolysis. XRD studies reveal that the material deposited is polycrystalline SnO2 and have tetragonal structure. It is observed that films are highly orientated along (200 direction. The direct optical band gap energy for the F: SnO2 films are found to be 4.15 eV. Gas sensing properties of the sensor were checked against combustible gases like H2, CO2 CO, C3H8, CH4.The H2 sensitivity of the F-doped SnO2 sensor was found to be increased. The increase in the sensitivity is discussed in terms of increased resistivity and reduced permeation of gaseous oxygen into the underlying sensing layer due to the surface modification of the sensor.

  3. Cavity closure during compression between semi-closed die using superplastic tin-lead alloy

    International Nuclear Information System (INIS)

    Zaid, A. I. O.; Al-Tamimi, M. M.

    2013-01-01

    Superplasticity is a feature of a material or alloy, which allows the material to deform plastically to an extremely large strain at low values of stress under certain loading conditions of strain rate and temperature. Eutectic tin-lead alloy is a practical material for research investigations as it possesses a superplastic behavior at room temperature and low strain rate which makes it a useful tool in simulating the ordinary engineering materials at high strain rate and temperature, and has been extensively used as a model material. In this paper, superplastic tin-lead alloy was used at room temperature to simulate the closure of cavities in steels at high temperatures in the hot region under dynamic loading (high strain rate) under the effect of compressive loads using semi-closed dies (modified dies) with 45 degree inclination and compare the results from these dies with those of flat platens (open dies) published previously. Hollow specimens having different values of bore diameter (Db) to outer diameter (Dout), of the same height and volume were investigated under 40% height reduction. The cavity closure for each specimen was determined. Comparison is made between flat platens and semi-closed dies regarding cavity closure based on bore diameter, bore volume, reduction percentage in bore diameter and reduction percentage in bore volume, at the 40% reduction in height. It was found that modifying the platens (45 degree inclination) resulted in lower values of bore diameters and volume i.e. higher values of reduction in bore diameters and volumes percentages irrespective of the value of bore diameter and the ratio of Db/Dout. (author)

  4. The fracture of concrete under explosive shock loading

    International Nuclear Information System (INIS)

    Watson, A.J.; Sanderson, A.J.

    1982-01-01

    Concrete fracture close to the point of application of high explosive shock pressures has been studied experimentally by placing an explosive charge on the edge of a concrete slab. The extent of the crushing and cracking produced by a semi cylindrical diverging plane compressive stress pulse has been measured and complementary experiments gave the pressure transmitted at an explosive to concrete interface and the stress-strain relation for concrete at explosive strain rates. (orig.) [de

  5. Telomere dysfunction and cell survival: roles for distinctTIN2-containing complexes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sahn-Ho; Davalos, Albert R.; Heo, Seok-Jin; Rodier, Francis; Beausejour, Christian; Kaminker, Patrick; Campisi, Judith

    2006-11-07

    Telomeres are maintained by three DNA binding proteins, TRF1, TRF2 and POT1, and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. These and two other proteins form a soluble complex that may be the core telomere-maintenance complex. It is not clear whether subcomplexes exist or function in vivo. Here, we provide evidence for two TIN2 subcomplexes with distinct functions in human cells. TIN2 ablation by RNA interference caused telomere uncapping and p53-independent cell death in all cells tested. However, we isolated two TIN2 complexes from cell lysates, each selectively sensitive to a TIN2 mutant (TIN2-13, TIN2-15C). In cells with wild-type p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere uncapping and eventual growth arrest. In cells lacking p53 function, TIN215C more than TIN2-13 caused genomic instability and cell death. Thus, TIN2 subcomplexes likely have distinct functions in telomere maintenance, and may provide selective targets for eliminating cells with mutant p53.

  6. The effect of the atmosphere on the optical properties of as-synthesized colloidal indium tin oxide

    International Nuclear Information System (INIS)

    Capozzi, Charles J; Joshi, Salil; Gerhardt, Rosario A; Ivanov, Ilia N

    2009-01-01

    The optical properties of indium tin oxide (ITO) have often been explored when it is in the form of deposited thin films. In this study, a colloidal chemistry approach is taken to investigate the influence of the atmosphere on the optical properties of ITO nanoparticles. X-ray diffraction (XRD), transmission electron microscopy (TEM), absorption spectroscopy and photoluminescence (PL) were used to characterize colloidal ITO samples, synthesized under aerated and inert conditions, with the same composition. In both cases, the ITO can be completely dispersed in a non-polar solvent without any evidence of agglomeration. For the ITO made in air, the nanoparticle-solvent solution exhibits a pale green color, and XRD and TEM indicate an average particle size of ∼7 nm and small shrinkage in the lattice structure. When the ITO is synthesized under inert conditions, the solution turns blue, and XRD and TEM indicate an average particle size of ∼8 nm and even less strain in the lattice than for the ITO synthesized under aerated conditions. The change in color and lattice strain is attributed to the difference in oxygen vacancy concentration for the ITO nanoparticles synthesized under aerated and inert conditions, which exhibit different optical band gap values of 3.89 eV and 4.05 eV, respectively. Our work here shows that thin film deposition or sintering steps may not be required for studying the optical properties of as-synthesized ITO nanoparticles.

  7. Self-consistent technique for estimating the dynamic yield strength of a shock-loaded material

    International Nuclear Information System (INIS)

    Asay, J.R.; Lipkin, J.

    1978-01-01

    A technique is described for estimating the dynamic yield stress in a shocked material. This method employs reloading and unloading data from a shocked state along with a general assumption of yield and hardening behavior to estimate the yield stress in the precompressed state. No other data are necessary for this evaluation, and, therefore, the method has general applicability at high shock pressures and in materials undergoing phase transitions. In some special cases, it is also possible to estimate the complete state of stress in a shocked state. Using this method, the dynamic yield strength of aluminum at 2.06 GPa has been estimated to be 0.26 GPa. This value agrees reasonably well with previous estimates

  8. Simulation on the shock attenuation behavior of coupled RHA and ...

    African Journals Online (AJOL)

    This paper presents the shock attenuation behavior of engineering materials namely Rolled Homogenous Armor (RHA) and sandwich composite when subject to blast loadings. Blast loading on sandwich composite structure and monolithic material are investigated using LSDYNA 3D with Arbitrary LagrangianEulerian ...

  9. Use of an Ultrasonic/Sonic Driller/Corer to Obtain Sample Powder for CHEMIN, a Combined XRD/XRF Instrument

    Science.gov (United States)

    Chipera, S. J.; Bish, D. L.; Vaniman, D. T.; Sherrit, S.; Bar-Cohen, Y.; Sarrazin, P.; Blake, D. F.

    2003-01-01

    A miniature CHEMIN XRD/XRF (X-Ray Diffraction/X-Ray Fluourescence) instrument is currently being developed for definitive mineralogic analysis of soils and rocks on Mars. One of the technical issues that must be addressed in order to enable XRD analysis on an extraterrestrial body is how best to obtain a representative sample powder for analysis. For XRD powder diffraction analyses, it is beneficial to have a fine-grained sample to reduce preferred orientation effects and to provide a statistically significant number of crystallites to the X-ray beam. Although a 2-dimensional detector as used in the CHEMIN instrument will produce good results with poorly prepared powders, the quality of the data will improve if the sample is fine-grained and randomly oriented. An Ultrasonic/Sonic Driller/Corer (USDC) currently being developed at JPL is an effective mechanism of sampling rock to produce cores and powdered cuttings. It requires low axial load (XRD/XRF spectrometer such as CHEMIN, powders obtained from the JPL ultrasonic drill were analyzed and the results were compared to carefully prepared powders obtained using a laboratory bench scale Retsch mill.

  10. Telomere dysfunction and cell survival: Roles for distinct TIN2-containing complexes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sahn-ho; Davalos, Albert R.; Heo, Seok-Jin; Rodier, Francis; Zou, Ying; Beausejour, Christian; Kaminker, Patrick; Yannone, Steven M.; Campisi, Judith

    2007-10-02

    Telomeres are maintained by three DNA binding proteins (TRF1, TRF2 and POT1), and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. Along with two other proteins, TPP1 and hRap1, these form a soluble complex that may be the core telomere maintenance complex. It is not clear whether sub-complexes also exist in vivo. We provide evidence for two TIN2 sub-complexes with distinct functions in human cells. We isolated these two TIN2 sub-complexes from nuclear lysates of unperturbed cells and cells expressing TIN2 mutants TIN2-13, TIN2-15C, which cannot bind TRF2 or TRF1, respectively. In cells with wild-type p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere uncapping and eventual growth arrest. In cells lacking p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere dysfunction and cell death. Our findings suggest that distinct TIN2 complexes exist, and that TIN2-15C-sensitive subcomplexes are particularly important for cell survival in the absence of functional p53.

  11. Effects of laser shock processing on electrochemical corrosion resistance of ANSI 304 stainless steel weldments after cavitation erosion

    International Nuclear Information System (INIS)

    Zhang, L.; Zhang, Y.K.; Lu, J.Z.; Dai, F.Z.; Feng, A.X.; Luo, K.Y.; Zhong, J.S.; Wang, Q.W.; Luo, M.; Qi, H.

    2013-01-01

    Highlights: ► Weldments were done with laser shock processing impacts after cavitation erosion. ► Laser shock processing enhanced the erosion and corrosion resistance of weldments. ► Tensile residual stress and surface roughness decreased by laser shock processing. ► Microstructure was observed to explain the improvement by laser shock processing. ► Obvious passivation areas occurred with laser shock processing impacts. - Abstract: Effects of laser shock processing (LSP) on electrochemical corrosion resistance of weldments after cavitation erosion were investigated by X-ray diffraction (XRD) technology, scanning electron microscope (SEM), roughness tester and optical microscope (OM). Some main factors to influence erosion and corrosion of weldments, residual stresses, surface roughness, grain refinements and slip, were discussed in detail. Results show that LSP impacts can induce compressive residual stresses, decrease surface roughness, refine grains and generate the slip. Thus, the erosion and corrosion resistance with LSP impacts is improved.

  12. Preliminary study of tin slag concrete mixture

    Science.gov (United States)

    Hashim, Mohd Jamil; Mansor, Ishak; Pauzi Ismail, Mohamad; Sani, Suhairy; Azmi, Azhar; Sayuti, Shaharudin; Zaidi Ibrahim, Mohd; Adli Anuar, Abul; Rahim, Abdul Adha Abdul

    2018-01-01

    The study focuses on practices to facilitate tin smelting industry to reduce radioactive waste product (Tin Slag) by diluting its radioactivity to a safe level and turning it to a safer infrastructural building product. In the process the concrete mix which include Portland cement, sand, tin slag, water and plasticizer are used to produce interlocking brick pavements, piles and other infrastructural products. The mixing method follows DOE (UK) standard method of mixing targeted at in selected compressive strength suitable for its function and durability. A batching machine is used in the mixing and six test cubes are produced for the test. The testing equipment used are a compressional machine, ultrasonic measurement and a Geiger Muller counter to evaluate of the concrete mix to find the lowest emission of radiation surface dose without compromising the strength of concrete mix. The result obtained indicated the radioactivity of tin slag in the mixing process has reduced to background level that is 0.5μSv/h while the strength and workability of the concrete has not been severely affected. In conclusion, the concrete mix with tin slag has shown the potential it can be turned into a safe beneficial infrastructural product with good strength.

  13. Individual and combined effects of organic, toxic, and hydraulic shocks on sequencing batch reactor in treating petroleum refinery wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Mizzouri, Nashwan Sh., E-mail: nashwan_mizzouri@yahoo.com [Department of Civil Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Department of Civil Engineering, University of Duhok, Kurdistan (Iraq); Shaaban, Md Ghazaly [Department of Civil Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)

    2013-04-15

    Highlights: ► This research focuses on the combined impact of shock loads on the PRWW treatment. ► System failure resulted when combined shock of organic and hydraulic was applied. ► Recovery was achieved by replacing glucose with PRWW and OLR was decreased to half. ► Worst COD removals were 68.9, and 57.8% for organic, and combined shocks. -- Abstract: This study analyzes the effects of toxic, hydraulic, and organic shocks on the performance of a lab-scale sequencing batch reactor (SBR) with a capacity of 5 L. Petroleum refinery wastewater (PRWW) was treated with an organic loading rate (OLR) of approximately 0.3 kg chemical oxygen demand (COD)/kg MLSS d at 12.8 h hydraulic retention time (HRT). A considerable variation in the COD was observed for organic, toxic, hydraulic, and combined shocks, and the worst values observed were 68.9, 77.1, 70.2, and 57.8%, respectively. Improved control of toxic shock loads of 10 and 20 mg/L of chromium (VI) was identified. The system was adversely affected by the organic shock when a shock load thrice the normal value was used, and this behavior was repeated when the hydraulic shock was 4.8 h HRT. The empirical recovery period was greater than the theoretical period because of the inhibitory effects of phenols, sulfides, high oil, and grease in the PRWW. The system recovery rates from the shocks were in the following order: toxic, organic, hydraulic, and combined shocks. System failure occurred when the combined shocks of organic and hydraulic were applied. The system was resumed by replacing the PRWW with glucose, and the OLR was reduced to half its initial value.

  14. Analytical solutions of hypersonic type IV shock - shock interactions

    Science.gov (United States)

    Frame, Michael John

    An analytical model has been developed to predict the effects of a type IV shock interaction at high Mach numbers. This interaction occurs when an impinging oblique shock wave intersects the most normal portion of a detached bow shock. The flowfield which develops is complicated and contains an embedded jet of supersonic flow, which may be unsteady. The jet impinges on the blunt body surface causing very high pressure and heating loads. Understanding this type of interaction is vital to the designers of cowl lips and leading edges on air- breathing hypersonic vehicles. This analytical model represents the first known attempt at predicting the geometry of the interaction explicitly, without knowing beforehand the jet dimensions, including the length of the transmitted shock where the jet originates. The model uses a hyperbolic equation for the bow shock and by matching mass continuity, flow directions and pressure throughout the flowfield, a prediction of the interaction geometry can be derived. The model has been shown to agree well with the flowfield patterns and properties of experiments and CFD, but the prediction for where the peak pressure is located, and its value, can be significantly in error due to a lack of sophistication in the model of the jet fluid stagnation region. Therefore it is recommended that this region of the flowfield be modeled in more detail and more accurate experimental and CFD measurements be used for validation. However, the analytical model has been shown to be a fast and economic prediction tool, suitable for preliminary design, or for understanding the interactions effects, including the basic physics of the interaction, such as the jet unsteadiness. The model has been used to examine a wide parametric space of possible interactions, including different Mach number, impinging shock strength and location, and cylinder radius. It has also been used to examine the interaction on power-law shaped blunt bodies, a possible candidate for

  15. Fabrication of nickel oxide and Ni-doped indium tin oxide thin films using pyrosol process

    International Nuclear Information System (INIS)

    Nakasa, Akihiko; Adachi, Mami; Usami, Hisanao; Suzuki, Eiji; Taniguchi, Yoshio

    2006-01-01

    Organic light emitting diodes (OLEDs) need indium tin oxide (ITO) anodes with highly smooth surface. The work function of ITO, about 4.8 eV, is generally rather lower than the optimum level for application to OLEDs. In this work, NiO was deposited by pyrosol process on pyrosol ITO film to increase the work function of the ITO for improving the performance of OLEDs. It was confirmed that NiO was successfully deposited on pyrosol ITO film and the NiO deposition increased the work function of pyrosol ITO, using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and atmospheric photoelectron spectroscopy. Furthermore, doping ITO with Ni succeeded in producing the Ni-doped ITO film with high work function and lower sheet resistance

  16. Studies on the surface modification of TiN coatings using MEVVA ion implantation with selected metallic species

    International Nuclear Information System (INIS)

    Ward, L.P.; Purushotham, K.P.; Manory, R.R.

    2016-01-01

    Highlights: • Reduced surface roughness was observed after ion implantation. • W implantation increased residual stress. • Reduced friction and wear accompanied Mo implantation. • Mo implanted layer was more resistant to breakdown during wear testing. • Ion implantation effects can be complex on various implanting species properties. - Abstract: Improvement in the performance of TiN coatings can be achieved using surface modification techniques such as ion implantation. In the present study, physical vapor deposited (PVD) TiN coatings were implanted with Cr, Zr, Nb, Mo and W using the metal evaporation vacuum arc (MEVVA) technique at a constant nominal dose of 4 × 10 16 ions cm −2 for all species. The samples were characterized before and after implantation, using Rutherford backscattering (RBS), glancing incident angle X-ray diffraction (GIXRD), atomic force microscopy (AFM) and optical microscopy. Friction and wear studies were performed under dry sliding conditions using a pin-on-disc CSEM Tribometer at 1 N load and 450 m sliding distance. A reduction in the grain size and surface roughness was observed after implantation with all five species. Little variation was observed in the residual stress values for all implanted TiN coatings, except for W implanted TiN which showed a pronounced increase in compressive residual stress. Mo-implanted samples showed a lower coefficient of friction and higher resistance to breakdown during the initial stages of testing than as-received samples. Significant reduction in wear rate was observed after implanting with Zr and Mo ions compared with unimplanted TiN. The presence of the Ti 2 N phase was observed with Cr implantation.

  17. XRD and 119Sn Moessbauer spectroscopy characterization of SnSe obtained from a simple chemical route

    International Nuclear Information System (INIS)

    Bernardes-Silva, Ana Claudia; Mesquita, A.F.; Moura de Neto, E.; Porto, A.O.; Ardisson, J.D.; Lima, G.M. de; Lameiras, F.S.

    2005-01-01

    Crystalline tin selenide semiconductor was synthesized by a chemical route. Selenium powder reacted with potassium boronhydride, giving a soluble selenium species potassium seleniumhydride. The reaction of potassium seleniumhydride with tin chloride produced crystalline tin selenide, which was characterized by X-ray diffraction, 119 Sn Moessbauer spectroscopy and scanning electronic microscopy. The material was thermally treated, in nitrogen flow, at 300 and 600 deg. C for 2 h and the particle size evolution was studied by X-ray diffraction. The X-ray diffraction and 119 Sn Moessbauer results showed that a mixture of tin oxides and orthorhombic tin selenide was obtained

  18. Effect of plasma molybdenized buffer layer on adhesive properties of TiN film coated on Ti6Al4V alloy

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Lin, E-mail: qinlin@tyut.edu.cn; Yi, Hong; Kong, Fanyou; Ma, Hua; Guo, Lili; Tian, Linhai; Tang, Bin

    2017-05-01

    Highlights: • A molybdenized layer was prepared as a buffer layer under TiN film on Ti6Al4V. • The molybdenized layer can enhance adhesion strength of PVD coatings effectively. • The duplex treated samples increase elastic energy ratio in the impact tests. • The enhancement attributes to the hardness improvement and inverted-S shape elastic modulus profile of the modified layer. - Abstract: Effect of molybdenized buffer layer on adhesion strength of TiN film on Ti6Al4V alloy was investigated. The buffer layer composed of a dense molybdenum deposition layer, a rapid drop zone and a slow fall zone was prepared using double glow plasma surface alloying technique. Scratch tests and low energy repeated impact tests were adopted to comparatively evaluate the duplex treated layers and the single TiN samples. The results show that the critical load was increased from 62 N for the single TiN film to over 100 N for the duplex treated layer. The volume of impact pit, formed in impact tests, of the single TiN samples is 9.15 × 10{sup 6} μm{sup 3}, and about 1.5 times than that of the duplex treated samples. The Leeb hardness values reveal that about 70% impact energy was transferred to the single TiN samples to generate permanent deformation, while that was only about 47% for the duplex treated samples. The mechanism of improving adhesion strength is attributed to synergistic effect due to an inverted-S shape elastic modulus distribution produced by the molybdenized layer.

  19. Microstructure and growth mechanism of tin whiskers on RESn3 compounds

    International Nuclear Information System (INIS)

    Li Caifu; Liu Zhiquan

    2013-01-01

    Graphical abstract: Large amount of intact tin whiskers were firstly prepared without post handling, and their microstructures were investigated systematically with TEM. A growth model was proposed to explain the observed growth characteristics from Sn–RE alloys. - Abstract: An exclusive method was developed to prepare intact tin whiskers as transmission electron microscope specimens, and with this technique in situ observation of tin whisker growth from RESn 3 (RE = Nd, La, Ce) film specimen was first achieved. Electron irradiation was discovered to have an effect on the growth of a tin whisker through its root. Large quantities of tin whiskers with diameters from 20 nm to 10 μm and lengths ranging from 50 nm to 500 μm were formed at a growth rate of 0.1–1.8 nm s −1 on the surface of RESn 3 compounds. Most (>85%) of these tin whiskers have preferred growth directions of 〈1 0 0〉, 〈0 0 1〉, 〈1 0 1〉 and 〈1 0 3〉, as determined by statistics. This kind of tin whisker is single-crystal β-Sn even if it has growth striations, steps and kinks, and no dislocations or twin or grain boundaries were observed within the whisker body. RESn 3 compounds undergo selective oxidation during whisker growth, and the oxidation provides continuous tin atoms for tin whisker growth until they are exhausted. The driving force for whisker growth is the compressive stress resulting from the restriction of the massive volume expansion (38–43%) during the oxidation by the surface RE(OH) 3 layer. Tin atoms diffuse and flow to feed the continuous growth of tin whiskers under a compressive stress gradient formed from the extrusion of tin atoms/clusters at weak points on the surface RE(OH) 3 layers. A growth model was proposed to discuss the characteristics and growth mechanism of tin whiskers from RESn 3 compounds.

  20. Experimental investigation on load capacity and wear rate of ...

    African Journals Online (AJOL)

    In this study, a boundary condition test was conducted on journal bearing materials (Al-Tin alloy and Lead-Bronze alloy) used in Peugeot and Toyota automobiles were examined at room temperature conditions. The results of experiments are presented in graphics which proves that the average loading capacities, PV factor ...

  1. NASA GSFC Tin Whisker Homepage http://nepp.nasa.gov/whisker

    Science.gov (United States)

    Shaw, Harry

    2000-01-01

    The NASA GSFC Tin Whisker Homepage provides general information and GSFC Code 562 experimentation results regarding the well known phenomenon of tin whisker formation from pure tin plated substrates. The objective of this www site is to provide a central repository for information pertaining to this phenomenon and to provide status of the GSFC experiments to understand the behavior of tin whiskers in space environments. The Tin Whisker www site is produced by Code 562. This www site does not provide information pertaining to patented or proprietary information. All of the information contained in this www site is at the level of that produced by industry and university researchers and is published at international conferences.

  2. Effect of Cr doping on the structural, morphological, optical and electrical properties of indium tin oxide films

    Science.gov (United States)

    Mirzaee, Majid; Dolati, Abolghasem

    2015-03-01

    We report on the preparation and characterization of high-purity chromium (0.5-2.5 at.%)-doped indium tin oxide (ITO, In:Sn = 90:10) films deposited by sol-gel-mediated dip coating. The effects of different Cr-doping contents on structural, morphological, optical and electrical properties of the films were characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), UV-Vis spectroscopy and four-point probe methods. XRD showed high phase purity cubic In2O3 and indicated a contraction of the lattice with Cr doping. FESEM micrographs show that grain size decreased with increasing the Cr-doping content. A method to determine chromium species in the sample was developed through the decomposition of the Cr 2 p XPS spectrum in Cr6+ and Cr3+ standard spectra. Optical and electrical studies revealed that optimum opto-electronic properties, including minimum sheet resistance of 4,300 Ω/Sq and an average optical transmittance of 85 % in the visible region with a band gap of 3.421 eV, were achieved for the films doped with Cr-doping content of 2 at.%.

  3. Assessment of CFD capability for prediction of hypersonic shock interactions

    Science.gov (United States)

    Knight, Doyle; Longo, José; Drikakis, Dimitris; Gaitonde, Datta; Lani, Andrea; Nompelis, Ioannis; Reimann, Bodo; Walpot, Louis

    2012-01-01

    The aerothermodynamic loadings associated with shock wave boundary layer interactions (shock interactions) must be carefully considered in the design of hypersonic air vehicles. The capability of Computational Fluid Dynamics (CFD) software to accurately predict hypersonic shock wave laminar boundary layer interactions is examined. A series of independent computations performed by researchers in the US and Europe are presented for two generic configurations (double cone and cylinder) and compared with experimental data. The results illustrate the current capabilities and limitations of modern CFD methods for these flows.

  4. Surface flaw in a thermally shocked hollow cylinder

    International Nuclear Information System (INIS)

    Kobayashi, A.S.; Emery, A.F.; Polvanich, N.; Love, W.J.

    1975-01-01

    The objective of this paper is to illustrate a procedure for estimating the stress intensity factors of a semi-elliptical crack located in the inner or outer surface of a thermally shocked hollow cylinder. The first step in this procedure is to estimate the transient thermal elastic stresses induced by sudden cooling of an uncracked cylinder by numerically evaluating standard heat transfer and thermal stress formulae. The stresses at the location of the crack surface in the uncracked cylinder are eliminated by the method of superposition in order to obtain a stress free crack surface. The stress intensity factors are then determined by a judicious use of two sets of solutions, one set involving stress intensity factors for a semi-elliptical crack in a flat plate and subjected to a polynomial distribution of pressure loading, and another set involving single-edge notched plates with prescribed edge-displacements and single-edge internally or externally notched cylinders with thermal shock loading. The former solutions are determined by the alternating technique in three-dimensional fracture mechanics with a fourth order polynomial pressure distribution on the crack surface where both the front and back surface effects are accounted for. The latter solutions involve two-dimensional finite element solutions of single-edge notched plates with prescribed edge-displacements and single-edge notched cylinders with thermal shock loading. By comparing these two two-dimensional solutions, an estimate of the effect of the cylindrical curvature on an edge-cracked plate is obtained. The combination of these two sets of solutions thus yields an estimate of the stress intensity factor in an internal and external semi-elliptical crack in a thermally shocked cylinder

  5. Shock Mounting for Heavy Machines

    Science.gov (United States)

    Thompson, A. R.

    1984-01-01

    Elastomeric bearings eliminate extraneous forces. Rocket thrust transmitted from motor to load cells via support that absorbs extraneous forces so they do not affect accuracy of thrust measurements. Adapter spoked cone fits over forward end of rocket motor. Shock mounting developed for rocket engines under test used as support for heavy machines, bridges, or towers.

  6. Atomic dynamics of tin nanoparticles embedded into porous glass

    Energy Technology Data Exchange (ETDEWEB)

    Parshin, P. P.; Zemlyanov, M. G., E-mail: zeml@isssph.kiae.ru; Panova, G. Kh.; Shikov, A. A. [Russian Research Centre Kurchatov Institute (Russian Federation); Kumzerov, Yu. A.; Naberezhnov, A. A. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Sergueev, I.; Crichton, W. [European Synchrotron Radiation Facility (France); Chumakov, A. I. [Russian Research Centre Kurchatov Institute (Russian Federation); Rueffer, R. [European Synchrotron Radiation Facility (France)

    2012-03-15

    The method of resonant nuclear inelastic absorption of synchrotron radiation has been used to study the phonon spectrum for tin nanoparticles (with a natural isotope mixture) embedded into a porous glassy (silica) matrix with an average pore diameter of 7 nm in comparison to the analogous spectrum of bulk tin enriched with {sup 119}Sn isotope. Differences between the spectra have been observed, which are related to both the dimensional effects and specific structural features of the porous glass-tin nanocomposite. Peculiarities in the dynamics of tin atoms embedded into nanopores of glass are interpreted in terms of a qualitative model of the nanocomposite structure.

  7. Atomic dynamics of tin nanoparticles embedded into porous glass

    International Nuclear Information System (INIS)

    Parshin, P. P.; Zemlyanov, M. G.; Panova, G. Kh.; Shikov, A. A.; Kumzerov, Yu. A.; Naberezhnov, A. A.; Sergueev, I.; Crichton, W.; Chumakov, A. I.; Rüffer, R.

    2012-01-01

    The method of resonant nuclear inelastic absorption of synchrotron radiation has been used to study the phonon spectrum for tin nanoparticles (with a natural isotope mixture) embedded into a porous glassy (silica) matrix with an average pore diameter of 7 nm in comparison to the analogous spectrum of bulk tin enriched with 119 Sn isotope. Differences between the spectra have been observed, which are related to both the dimensional effects and specific structural features of the porous glass-tin nanocomposite. Peculiarities in the dynamics of tin atoms embedded into nanopores of glass are interpreted in terms of a qualitative model of the nanocomposite structure.

  8. On the shock response of the magnesium alloy Elektron 675

    Science.gov (United States)

    Hazell, Paul; Appleby-Thomas, Gareth; Siviour, Clive; Wielewski, Euan

    2011-06-01

    Alloying elements such as aluminium, zinc or rare-earths allow precipitation hardening of magnesium (Mg). The low densities of such strengthened Mg alloys have led to their adoption as aerospace materials and (more recently) they are being considered as armour materials. Consequently, understanding their response to high-strain rate loading is becoming increasingly important. Here, the plate-impact technique was employed to measure longitudinal stress evolution in armour-grade wrought Mg-alloy Elektron 675 under 1D shock loading. The strength and spall behaviour was interrogated, with an estimate made of the material's Hugoniot elastic limit. Finally, electron backscatter diffraction (EBSD) techniques were employed to investigate post-shock microstructural changes.

  9. Intrinsic and Extrinsic Ferromagnetism in Co-Doped Indium Tin Oxide Revealed Using X-Ray Magnetic Circular Dichroism

    Directory of Open Access Journals (Sweden)

    A. M. H. R. Hakimi

    2017-01-01

    Full Text Available The effects of high-temperature annealing on ferromagnetic Co-doped Indium Tin Oxide (ITO thin films have been investigated using X-ray diffraction (XRD, magnetometry, and X-Ray Magnetic Circular Dichroism (XMCD. Following annealing, the magnetometry results indicate the formation of Co clusters with a significant increase in the saturation magnetization of the thin films arising from defects introduced during cluster formation. However, sum rule analysis of the element-specific XMCD results shows that the magnetic moment at the Co sites is reduced after annealing. The effects of annealing demonstrate that the ferromagnetism observed in the as-deposited Co-doped ITO films arises from intrinsic defects and cannot be related to the segregation of metallic Co clusters.

  10. Proton transport properties of tin phosphate, chromotropic acid ...

    Indian Academy of Sciences (India)

    The functionalized materials of tin (IV) phosphate (SnP) like chromotropic acid anchored tin ... elemental analysis (ICP–AES), thermal analysis, X-ray analysis and FTIR spectroscopy. .... nal level below 1 V, interfaced to a minicomputer for data.

  11. A Numerical Method for Blast Shock Wave Analysis of Missile Launch from Aircraft

    Directory of Open Access Journals (Sweden)

    Sebastian Heimbs

    2015-01-01

    Full Text Available An efficient empirical approach was developed to accurately represent the blast shock wave loading resulting from the launch of a missile from a military aircraft to be used in numerical analyses. Based on experimental test series of missile launches in laboratory environment and from a helicopter, equations were derived to predict the time- and position-dependent overpressure. The method was finally applied and validated in a structural analysis of a helicopter tail boom under missile launch shock wave loading.

  12. Constitutive modeling of shock response of PTFE

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Eric N [Los Alamos National Laboratory; Reanyansky, Anatoly D [DSTO, AUSTRALIA; Bourne, Neil K [AWE, UK; Millett, Jeremy C F [AWE, UK

    2009-01-01

    The PTFE (polytetrafluoroethylene) material is complex and attracts attention of the shock physics researchers because it has amorphous and crystalline components. In turn, the crystalline component has four known phases with the high pressure transition to phase III. At the same time, as has been recently studied using spectrometry, the crystalline region is growing with load. Stress and velocity shock-wave profiles acquired recently with embedded gauges demonstrate feature that may be related to impedance mismatches between the regions subjected to some transitions resulting in density and modulus variations. We consider the above mentioned amorphous-to-crystalline transition and the high pressure Phase II-to-III transitions as possible candidates for the analysis. The present work utilizes a multi-phase rate sensitive model to describe shock response of the PTFE material. One-dimensional experimental shock wave profiles are compared with calculated profiles with the kinetics describing the transitions. The objective of this study is to understand the role of the various transitions in the shock response of PTFE.

  13. Studies on Nanocrystalline TiN Coatings Prepared by Reactive Plasma Spraying

    Directory of Open Access Journals (Sweden)

    Dong Yanchun

    2008-01-01

    Full Text Available Titanium nitride (TiN coatings with nanostructure were prepared on the surface of 45 steel (Fe-0.45%C via reactive plasma spraying (denoted as RPS Ti powders using spraying gun with self-made reactive chamber. The microstructural characterization, phases constitute, grain size, microhardness, and wear resistance of TiN coatings were systematically investigated. The grain size was obtained through calculation using the Scherrer formula and observed by TEM. The results of X-ray diffraction and electron diffraction indicated that the TiN is main phase of the TiN coating. The forming mechanism of the nano-TiN was characterized by analyzing the SEM morphologies of surface of TiN coating and TiN drops sprayed on the surface of glass, and observing the temperature and velocity of plasma jet using Spray Watch. The tribological properties of the coating under nonlubricated condition were tested and compared with those of the AISI M2 high-speed steel and Al2O3 coating. The results have shown that the RPS TiN coating presents better wear resistance than the M2 high-speed steel and Al2O3 coating under nonlubricated condition. The microhardness of the cross-section and longitudinal section of the TiN coating was tested. The highest hardness of the cross-section of TiN coating is 1735.43HV100 g.

  14. Interface analysis of embedded chip resistor device package and its effect on drop shock reliability.

    Science.gov (United States)

    Park, Se-Hoon; Kim, Sun Kyoung; Kim, Young-Ho

    2012-04-01

    In this study, the drop reliability of an embedded passive package is investigated under JESD22-B111 condition. Chip resistors were buried in a PCB board, and it was electrically interconnected by electroless and electrolytic copper plating on a tin pad of a chip resistor without intermetallic phase. However tin, nickel, and copper formed a complex intermetallic phase, such as (Cu, Ni)6Sn5, (Cu, Ni)3Sn, and (Ni, Cu)3Sn2, at the via interface and via wall after reflow and aging. Since the amount of the tin layer was small compared with the solder joint, excessive intermetallic layer growth was not observed during thermal aging. Drop failures are always initiated at the IMC interface, and as aging time increases Cu-Sn-Ni IMC phases are transformed continuously due to Cu diffusion. We studied the intermetallic formation of the Cu via interface and simulated the stress distribution of drop shock by using material properties and board structure of embedded passive boards. The drop simulation was conducted according to the JEDEC standard. It was revealed that the crack starting point related to failure fracture changed due to intermetallic phase transformation along the via interface, and the position where failure occurs experimentally agrees well with our simulation results.

  15. Development of in situ time-resolved Raman spectroscopy facility for dynamic shock loading in materials

    Science.gov (United States)

    Chaurasia, S.; Rastogi, V.; Rao, U.; Sijoy, C. D.; Mishra, V.; Deo, M. N.

    2017-11-01

    The transient state of excitation and relaxation processes in materials under shock compression can be investigated by coupling the laser driven shock facility with Raman spectroscopy. For this purpose, a time resolved Raman spectroscopy setup has been developed to monitor the physical and the chemical changes such as phase transitions, chemical reactions, molecular kinetics etc., under shock compression with nanosecond time resolution. This system consist of mainly three parts, a 2 J/8 ns Nd:YAG laser system used for generation of pump and probe beams, a Raman spectrometer with temporal and spectral resolution of 1.2 ns and 3 cm-1 respectively and a target holder in confinement geometry assembly. Detailed simulation for the optimization of confinement geometry targets is performed. Time resolved measurement of polytetrafluoroethylene (PTFE) targets at focused laser intensity of 2.2 GW/cm2 has been done. The corresponding pressure in the Aluminum and PTFE are 3.6 and 1.7 GPa respectively. At 1.7 GPa in PTFE, a red shift of 5 cm-1 is observed for the CF2 twisting mode (291 cm-1). Shock velocity in PTFE is calculated by measuring rate of change of ratios of the intensity of Raman lines scattered from shocked volume to total volume of sample in the laser focal spot along the laser axis. The calculated shock velocity in PTFE is found to be 1.64 ± 0.16 km/s at shock pressure of 1.7 GPa, for present experimental conditions.

  16. Behavior of prestressed concrete subjected to low temperatures and cyclic loading

    International Nuclear Information System (INIS)

    Berner, D.E.

    1984-01-01

    Concrete has exhibited excellent behavior in cryogenic containment vessels for several decades under essentially static conditions. Tests were conducted to determine the response of prestressed lightweight concrete subjected to high-intensity cyclic loading and simultaneous cryogenic thermal shock, simulating the relatively dynamic conditions encountered offshore or in seismic areas. Lightweight concrete has several attractive properties for cryogenic service including: (1) very low permeability, (2) good strain capacity, (3) relatively low thermal conductivity, and (4) a low modulus of elasticity. Experimental results indicated that the mechanical properties of plain lightweight concrete significantly increase with moisture content at low temperatures, while cyclic loading fatigue effects are reduced at low temperatures. Also, tests on uniaxially and on biaxially prestressed lightweight concrete both indicate that the test specimens performed well under severe cyclic loading and cryogenic thermal shock with only moderate reduction in flexural stiffness. Supplementary tests conducted in this study indicate that conventionally reinforced concrete degrades significantly faster than prestressed concrete when subjected to cyclic loading and thermal shock

  17. Load transfer in bovine plexiform bone determined by synchrotron x-ray diffraction

    International Nuclear Information System (INIS)

    Akhtar, R.; Daymond, M.; Almer, J.; Mummery, P.; The Univ. of Manchester; Queen's Univ.

    2008-01-01

    High-energy synchrotron x-ray diffraction (XRD) has been used to quantify load transfer in bovine plexiform bone. By using both wide-angle and small-angle XRD, strains in the mineral as well as the collagen phase of bone were measured as a function of applied compressive stress. We suggest that a greater proportion of the load is borne by the more mineralized woven bone than the lamellar bone as the applied stress increases. With a further increase in stress, load is shed back to the lamellar regions until macroscopic failure occurs. The reported data fit well with reported mechanisms of microdamage accumulation in bovine plexiform bone

  18. Preparation of porous titanium oxide films onto indium tin oxide for application in organic photovoltaic devices

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Andreia G. [Laboratorio de Dispositivos Nanoestruturados, Departamento de Fisica, Universidade Federal do Parana, Curitiba, Parana (Brazil); Mattos, Luana L.; Spada, Edna R.; Serpa, Rafael B.; Campos, Cristiani S. [Laboratorio de Sistemas Nanoestruturados, Departamento de Fisica, Universidade Federal de Santa Catarina, Florianopolis, Santa Catarina (Brazil); Grova, Isabel R.; Ackcelrud, Leni [Laboratorio de Polimeros Paulo Scarpa, Departamento de Quimica, Universidade Federal do Parana, Curitiba, Parana (Brazil); Reis, Francoise T.; Sartorelli, Maria L. [Laboratorio de Sistemas Nanoestruturados, Departamento de Fisica, Universidade Federal de Santa Catarina, Florianopolis, Santa Catarina (Brazil); Roman, Lucimara S., E-mail: lsroman@fisica.ufpr.br [Laboratorio de Dispositivos Nanoestruturados, Departamento de Fisica, Universidade Federal do Parana, Curitiba, Parana (Brazil)

    2012-05-01

    In this work, porous ordered TiO{sub 2} films were prepared through sol gel route by using a monolayer of polystyrene spheres as template on indium-tin oxide/glass substrate. These films were characterized by SEM, AFM, Raman spectroscopy, UV-vis absorbance and XRD. The UV-vis absorbance spectrum show a pseudo band gap (PBG) with maxima at 460 nm arising from the light scattering and partial or total suppression of the photon density of states, this PBG can be controlled by the size of the pore. We also propose the use of this porous film as electron acceptor electrode in organic photovoltaic cells; we show that devices prepared with porous titania displayed higher efficiencies than devices using compact titania films as electrode. Such behaviour was observed in both bilayer and bulk heterojunction devices.

  19. Preparation of porous titanium oxide films onto indium tin oxide for application in organic photovoltaic devices

    International Nuclear Information System (INIS)

    Macedo, Andreia G.; Mattos, Luana L.; Spada, Edna R.; Serpa, Rafael B.; Campos, Cristiani S.; Grova, Isabel R.; Ackcelrud, Leni; Reis, Françoise T.; Sartorelli, Maria L.; Roman, Lucimara S.

    2012-01-01

    In this work, porous ordered TiO 2 films were prepared through sol gel route by using a monolayer of polystyrene spheres as template on indium-tin oxide/glass substrate. These films were characterized by SEM, AFM, Raman spectroscopy, UV-vis absorbance and XRD. The UV-vis absorbance spectrum show a pseudo band gap (PBG) with maxima at 460 nm arising from the light scattering and partial or total suppression of the photon density of states, this PBG can be controlled by the size of the pore. We also propose the use of this porous film as electron acceptor electrode in organic photovoltaic cells; we show that devices prepared with porous titania displayed higher efficiencies than devices using compact titania films as electrode. Such behaviour was observed in both bilayer and bulk heterojunction devices.

  20. Electrooxidation of ethanol on novel multi-walled carbon nanotube supported platinum-antimony tin oxide nanoparticle catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Dao-Jun [School of Chemistry and Chemical Engineering, The Key Laboratory of Life-Organic Analysis, Qufu Normal University, Qufu, Shandong 273165 (China)

    2011-01-15

    We synthesize the new Pt based catalyst for direct ethanol fuel cells using novel multi-walled carbon nanotubes supported platinum-antimony tin oxide (Pt-ATO/MWCNT) nanoparticle as new catalyst support for the first time. The structure of Pt-ATO/MWCNT catalyst is characterized by transmission electron micrograph (TEM) and X-ray diffraction (XRD). The electrocatalytic properties of Pt-ATO/MWCNT catalyst for ethanol electrooxidation reactions are investigated by cyclic voltammetry (CV) and chronoamperometric experiments in acidic medium. The electrocatalytic activity for ethanol electrooxidation reaction shows that high carbon monoxide tolerance and good stability of Pt-ATO/MWCNT catalyst compared with Pt-SnO{sub 2}/MWCNT and commercial Pt/C are observed. These results imply that Pt-ATO/MWCNT catalyst has promising potential applications in direct alcohol fuel cells. (author)

  1. Perspectives of the Si3N4-TiN ceramic composite as a biomaterial and manufacturing of complex-shaped implantable devices by electrical discharge machining (EDM).

    Science.gov (United States)

    Bucciotti, Francesco; Mazzocchi, Mauro; Bellosi, Alida

    2010-01-01

    In this work we investigated the suitability of electroconductive silicon nitride/titanium nitride composite for biomedical implantable devices with particular attention on the processing route that allows the net-shaping of complex components by electrical discharge machining (EDM). The composite, constituted mainly of a beta-Si3N4, dispersed TiN grains and a glassy grain boundary phase, exhibited a low density and high hardness, strength and toughness. Bulk, surface characteristics and properties of the Si3N4-TiN composite were analyzed. After the EDM process, the microstructure of the machined surface was examined. The obtained results showed that the Si3N4-TiN ceramic composite together with the EDM manufacturing process might potentially play a key role in implantable load-bearing prosthesis applications.

  2. Patterning crystalline indium tin oxide by high repetition rate femtosecond laser-induced crystallization

    International Nuclear Information System (INIS)

    Cheng, Chung-Wei; Lin, Cen-Ying; Shen, Wei-Chih; Lee, Yi-Ju; Chen, Jenq-Shyong

    2010-01-01

    A method is proposed for patterning crystalline indium tin oxide (c-ITO) patterns on amorphous ITO (a-ITO) thin films by femtosecond laser irradiation at 80 MHz repetition rate followed by chemical etching. In the proposed approach, the a-ITO film is transformed into a c-ITO film over a predetermined area via the heat accumulation energy supplied by the high repetition rate laser beam, and the unirradiated a-ITO film is then removed using an acidic etchant solution. The fabricated c-ITO patterns are observed using scanning electron microscopy and cross-sectional transmission electron microscopy. The crystalline, optical, electrical properties were measured by X-ray diffraction, spectrophotometer, and four point probe station, respectively. The experimental results show that a high repetition rate reduces thermal shock and yields a corresponding improvement in the surface properties of the c-ITO patterns.

  3. Laser Structuring of Thin Layers for Flexible Electronics by a Shock Wave-induced Delamination Process

    Science.gov (United States)

    Lorenz, Pierre; Ehrhardt, Martin; Zimmer, Klaus

    The defect-free laser-assisted structuring of thin films on flexible substrates is a challenge for laser methods. However, solving this problem exhibits an outstanding potential for a pioneering development of flexible electronics. Thereby, the laser-assisted delamination method has a great application potential. At the delamination process: the localized removal of the layer is induced by a shock wave which is produced by a laser ablation process on the rear side of the substrate. In this study, the thin-film patterning process is investigated for different polymer substrates dependent on the material and laser parameters using a KrF excimer laser. The resultant structures were studied by optical microscopy and white light interferometry (WLI). The delamination process was tested at different samples (indium tin oxide (ITO) on polyethylene terephthalate (PET), epoxy-based negative photoresist (SU8) on polyimide (PI) and indium tin oxide/copper indium gallium selenide/molybdenum (ITO/CIGS/Mo) on PI.

  4. Applications of the rotating orientation XRD method to oriented materials

    International Nuclear Information System (INIS)

    Guo Zhenqi; Li Fei; Jin Li; Bai Yu

    2009-01-01

    The rotating orientation x-ray diffraction (RO-XRD) method, based on conventional XRD instruments by a modification of the sample stage, was introduced to investigate the orientation-related issues of such materials. In this paper, we show its applications including the determination of single crystal orientation, assistance in crystal cutting and evaluation of crystal quality. The interpretation of scanning patterns by RO-XRD on polycrystals with large grains, bulk material with several grains and oriented thin film is also presented. These results will hopefully expand the applications of the RO-XRD method and also benefit the conventional XRD techniques. (fast track communication)

  5. Analysis of compaction shock interactions during DDT of low density HMX

    Science.gov (United States)

    Rao, Pratap T.; Gonthier, Keith A.

    2017-01-01

    Deflagration-to-Detonation Transition (DDT) in confined, low density granular HMX occurs by a complex mechanism that involves compaction shock interactions within the material. Piston driven DDT experiments indicate that detonation is abruptly triggered by the interaction of a strong combustion-supported secondary shock and a piston-supported primary (input) shock, where the nature of the interaction depends on initial packing density and primary shock strength. These interactions influence transition by affecting dissipative heating within the microstructure during pore collapse. Inert meso-scale simulations of successive shock loading of low density HMX are performed to examine how dissipation and hot-spot formation are affected by the initial density, and the primary and secondary shock strengths. This information is used to formulate an ignition and burn model for low density HMX that accounts for the effect of shock densensitization on burn. Preliminary DDT predictions are presented that illustrate how primary shock strength affects the transition mechanism.

  6. Mechanical Properties of Shock-Damaged Rocks

    Science.gov (United States)

    He, Hongliang; Ahrens, T. J.

    1994-01-01

    Stress-strain tests were performed both on shock-damaged gabbro and limestone. The effective Young's modulus decreases with increasing initial damage parameter value, and an apparent work-softening process occurs prior to failure. To further characterize shock-induced microcracks, the longitudinal elastic wave velocity behavior of shock-damaged gabbro in the direction of compression up to failure was measured using an acoustic transmission technique under uniaxial loading. A dramatic increase in velocity was observed for the static compressive stress range of 0-50 MPa. Above that stress range, the velocity behavior of lightly damaged (D(sub 0) less than 0.1) gabbro is almost equal to unshocked gabbro. The failure strength of heavily-damaged (D(sub 0) greater than 0.1) gabbro is approx. 100-150 MPa, much lower than that of lightly damaged and unshocked gabbros (approx. 230-260 MPa). Following Nur's theory, the crack shape distribution was analyzed. The shock-induced cracks in gabbro appear to be largely thin penny-shaped cracks with c/a values below 5 x 10(exp -4). Moreover, the applicability of Ashby and Sammis's theory relating failure strength and damage parameter of shock-damaged rocks was examined and was found to yield a good estimate of the relation of shock-induced deficit in elastic modulus with the deficit in compressive strength.

  7. Selective Recovery of Mushistonite from Gravity Tailings of Copper–Tin Minerals in Tajikistan

    OpenAIRE

    Lei Sun; Yuehua Hu; Wei Sun; Zhiyong Gao; Mengjie Tian

    2017-01-01

    Tajikistan has abundant copper–tin resources. In this study, mineralogical analysis of copper–tin ores from the Mushiston deposit of Tajikistan indicates that tin mainly occurred in mushistonite, cassiterite, and stannite, while copper mainly occurred in mushistonite, malachite, azurite, and stannite. The total grades of tin (Sn) and copper (Cu) were 0.65% and 0.66%, respectively, and the dissemination size of copper–tin minerals ranged from 4 μm to over 200 μm. Coarse particles of copper–tin...

  8. X-ray diffraction measurements to determine longitudinal and transverse lattice deformation in shocked LiF

    International Nuclear Information System (INIS)

    Rigg, P.A.; Gupta, Y.M.

    2000-01-01

    Experimental methods using both single and multiple x-ray diffraction were developed to determine real time, lattice deformation in directions parallel and perpendicular to shock wave propagation in single crystals subjected to plate impact loading. Initial experiments used single diffraction to monitor the interplanar spacing change, parallel to the shock propagation direction, in LiF crystals shocked along the [111] and [100] directions. These measurements, in combination with the macroscopic volume compression, were used to determine the state of compression of the unit cell. Subsequent development of a multiple diffraction technique permitted simultaneous determination of both the longitudinal and transverse lattice deformations. The present results showed that shock compression, below 4 GPa, along the [111] orientation--which results in macroscopic elastic deformation - produced one-dimensional unit cell compression. In contrast, shock compression along the [100] orientation - which results in macroscopic elastic-plastic deformation--produced isotropic unit cell compression. The implications of the present results and the ability to make quantitative x-ray diffraction measurements under shock loading are discussed

  9. Understanding changes in cellulose crystalline structure of lignocellulosic biomass during ionic liquid pretreatment by XRD.

    Science.gov (United States)

    Zhang, Jiafu; Wang, Yixun; Zhang, Liye; Zhang, Ruihong; Liu, Guangqing; Cheng, Gang

    2014-01-01

    X-ray diffraction (XRD) was used to understand the interactions of cellulose in lignocellulosic biomass with ionic liquids (ILs). The experiment was designed in such a way that the process of swelling and solubilization of crystalline cellulose in plant cell walls was followed by XRD. Three different feedstocks, switchgrass, corn stover and rice husk, were pretreated using 1-butyl-3-methylimidazolium acetate ([C4mim][OAc]) at temperatures of 50-130°C for 6h. At a 5 wt.% biomass loading, increasing pretreatment temperature led to a drop in biomass crystallinity index (CrI), which was due to swelling of crystalline cellulose. After most of the crystalline cellulose was swollen with IL molecules, a low-order structure was found in the pretreated samples. Upon further increasing temperature, cellulose II structure started to form in the pretreated biomass samples as a result of solubilization of cellulose in [C4mim][OAc] and subsequent regeneration. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Study of particles clouds ejected under shock: the contributions of Photonic Doppler Velocimetry

    International Nuclear Information System (INIS)

    Prudhomme, Gabriel

    2014-01-01

    A metal plate subjected to a shock (tin, 10 GPa) undergoes a variety of damages such as spalling or the ejection of a cloud of particles. Two main mechanisms govern the formation of this cloud: the micro-jetting and the melting under shock. Photonic Doppler Velocimetry (PDV, a.k.a. LDV or het-V) is a multi-velocity time-resolved diagnostic. Developed from 2000's, the all-fibered conception makes its integration easy into shock experiments. The purpose of the thesis is to describe the contributions of PDV systems for high-velocity (several km/s) particle-cloud characterization, including micro-jetting cloud. This document presents a state of the art of shock generators, diagnostics and (numerical and experimental) studies involved in metallic micro-machined jetting. An extensive study of a PDV system is proposed. It leads to the definition of time-velocity spectrogram, evaluated in units of collected power, and a detection capability limit. Thanks to photon diffusion models, a threshold in the diameter of the measured particle is estimated. A PDV spectrogram simulation program is shown within the framework of particle clouds. Finally, several experimental campaigns are exposed. They emphasize the remarkable capacities of the system; results are compared to simulations. Diameter distributions are inferred using slowing down in air or in other gazes. Some radiometric analyses are also performed. (author) [fr

  11. Shock Response of Lightweight Adobe Masonry

    Science.gov (United States)

    Sauer, C.; Bagusat, F.; Heine, A.; Riedel, W.

    2018-04-01

    The behavior of a low density and low-strength building material under shock loading is investigated. The considered material is lightweight adobe masonry characterized by a density of 1.2 g/cm3 and a quasi-static uniaxial compressive strength of 2.8 MPa. Planar-plate-impact (PPI) tests with velocities in between 295 and 950 m/s are performed in order to obtain Hugoniot data and to derive parameters for an equation of state (EOS) that captures the occurring phenomenology of porous compaction and subsequent unloading. The resulting EOS description is validated by comparing the experimental free surface velocity time curves with those obtained by numerical simulations of the performed PPI tests. The non-linear compression behavior, including the pore compaction mechanism, constitutes a main ingredient for modelling the response of adobe to blast and high-velocity impact loading. We hence present a modeling approach for lightweight adobe which can be applied to such high rate loading scenarios in future studies. In general, this work shows that PPI tests on lightweight and low-strength geological materials can be used to extract Hugoniot data despite significant material inhomogeneity. Furthermore, we demonstrate that a homogenous material model is able to numerically describe such a material under shock compression and release with a reasonable accuracy.

  12. Evaluation of Defects of Thermal Barrier Coatings by Thermal Shock Test Using Eddy Current Testing

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Tae Hoon; Cho, Youn Ho; Lee, Joon Hyun [Pusan National University, Busan (Korea, Republic of); Oh, Jeong Seok; Lee, Koo Hyun [KIMM, Daejeon (Korea, Republic of)

    2009-10-15

    Periodical thermal shock can introduce defects in thermal barrier coating made by layers of CoNiCrAlY bond coating(BC) and ZrO{sub 2}-8wt%Y{sub 2}O{sub 3} ceramic top coating(TC) on Inconel-738 substrate using plasma spraying. Thermal shock test is performed by severe condition that is to heat until 1000 .deg. C and cool until 20 .deg. C. As the number of cycle is increased, the fatigue by thermal shock is also increased. After test, the micro-structures and mechanical characteristics of thermal barrier coating were investigated by SEM, XRD. The TGO layer of is Al{sub 2}O{sub 3} formed between BC and TC by periodical thermal shock test, and its change in thickness is inspected by eddy current test(ECT). By ECT test, it is shown that TGO and micro-crack can be detected and it is possible to predict the life of thermal barrier coating

  13. Transient Three-Dimensional Side Load Analysis of a Film Cooled Nozzle

    Science.gov (United States)

    Wang, Ten-See; Guidos, Mike

    2008-01-01

    Transient three-dimensional numerical investigations on the side load physics for an engine encompassing a film cooled nozzle extension and a regeneratively cooled thrust chamber, were performed. The objectives of this study are to identify the three-dimensional side load physics and to compute the associated aerodynamic side load using an anchored computational methodology. The computational methodology is based on an unstructured-grid, pressure-based computational fluid dynamics formulation, and a transient inlet history based on an engine system simulation. Ultimately, the computational results will be provided to the nozzle designers for estimating of effect of the peak side load on the nozzle structure. Computations simulating engine startup at ambient pressures corresponding to sea level and three high altitudes were performed. In addition, computations for both engine startup and shutdown transients were also performed for a stub nozzle, operating at sea level. For engine with the full nozzle extension, computational result shows starting up at sea level, the peak side load occurs when the lambda shock steps into the turbine exhaust flow, while the side load caused by the transition from free-shock separation to restricted-shock separation comes at second; and the side loads decreasing rapidly and progressively as the ambient pressure decreases. For the stub nozzle operating at sea level, the computed side loads during both startup and shutdown becomes very small due to the much reduced flow area.

  14. Influence of Thermal Annealing on the Microstructural Properties of Indium Tin Oxide Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Nam; Kim, Seung Bin [Pohang University of Science and Technology, Pohang (Korea, Republic of); Choi, Hyun Chul [Chonnam National University, Gwangju (Korea, Republic of)

    2012-01-15

    In this work, we studied the microstructural changes of ITO during the annealing process. ITO nanoparticles were prepared by the sol-gel method using indium tin hydroxide as the precursor. The prepared sample was investigated using TEM, powder XRD, XPS, DRIFT, and 2D correlation analysis. The O 1s XPS spectra suggested that the microstructural changes during the annealing process are closely correlated with the oxygen sites of the ITO nanoparticles. The temperature-dependent in situ DRIFT spectra suggested that In-OH in the terminal sites is firstly decomposed and, then, Sn-O-Sn is produced in the ITO nanoparticles during the thermal annealing process. Based on the 2D correlation analysis, we deduced the following sequence of events: 1483 (due to In-OH bending mode) → 2268, 2164 (due to In-OH stretching mode) → 1546 (due to overtones of Sn- O-Sn modes) → 1412 (due to overtones of Sn-O-Sn modes) cm{sup -1}.

  15. Kidney damage in extracorporeal shock wave lithotripsy: a numerical approach for different shock profiles.

    Science.gov (United States)

    Weinberg, Kerstin; Ortiz, Michael

    2009-08-01

    In shock-wave lithotripsy--a medical procedure to fragment kidney stones--the patient is subjected to hypersonic waves focused at the kidney stone. Although this procedure is widely applied, the physics behind this medical treatment, in particular the question of how the injuries to the surrounding kidney tissue arise, is still under investigation. To contribute to the solution of this problem, two- and three-dimensional numerical simulations of a human kidney under shock-wave loading are presented. For this purpose a constitutive model of the bio-mechanical system kidney is introduced, which is able to map large visco-elastic deformations and, in particular, material damage. The specific phenomena of cavitation induced oscillating bubbles is modeled here as an evolution of spherical pores within the soft kidney tissue. By means of large scale finite element simulations, we study the shock-wave propagation into the kidney tissue, adapt unknown material parameters and analyze the resulting stress states. The simulations predict localized damage in the human kidney in the same regions as observed in animal experiments. Furthermore, the numerical results suggest that in first instance the pressure amplitude of the shock wave impulse (and not so much its exact time-pressure profile) is responsible for damaging the kidney tissue.

  16. Molecular origins of anisotropic shock propagation in crystalline and amorphous polyethylene

    Science.gov (United States)

    O'Connor, Thomas C.; Elder, Robert M.; Sliozberg, Yelena R.; Sirk, Timothy W.; Andzelm, Jan W.; Robbins, Mark O.

    2018-03-01

    Molecular dynamics simulations are used to analyze shock propagation in amorphous and crystalline polyethylene. Results for the shock velocity Us are compared to predictions from Pastine's equation of state and hydrostatic theory. The results agree with Pastine at high impact velocities. At low velocities the yield stress becomes important, increasing the shock velocity and leading to anisotropy in the crystalline response. Detailed analysis of changes in atomic order reveals the origin of the anisotropic response. For shock along the polymer backbone, an elastic front is followed by a plastic front where chains buckle with a characteristic wavelength. Shock perpendicular to the chain backbone can produce plastic deformation or transitions to different orthorhombic or monoclinic structures, depending on the impact speed and direction. Tensile loading does not produce stable shocks: Amorphous systems craze and fracture while for crystals the front broadens linearly with time.

  17. Propagation of shock waves in elastic solids caused by cavitation microjet impact. II: Application in extracorporeal shock wave lithotripsy.

    Science.gov (United States)

    Zhong, P; Chuong, C J; Preminger, G M

    1993-07-01

    To better understand the mechanism of stone fragmentation during extracorporeal shock wave lithotripsy (ESWL), the model developed in Part I [P. Zhong and C.J. Chuong, J. Acoust. Soc. Am. 94, 19-28 (1993)] is applied to study cavitation microjet impingement and its resultant shock wave propagation in renal calculi. Impact pressure at the stone boundary and stress, strain at the propagating shock fronts in the stone were calculated for typical ESWL loading conditions. At the anterior surface of the stone, the jet induced compressive stress can vary from 0.82 approximately 4 times that of the water hammer pressure depending on the contact angles; whereas the jet-induced shear stress can achieve its maximum, with a magnitude of 30% approximately 54% of the water hammer pressure, near the detachment of the longitudinal (or P) wave in the solid. Comparison of model predictions with material failure strengths of renal calculi suggests that jet impact can lead to stone surface erosion by combined compressive and shear loadings at the jet impacting surface, and spalling failure by tensile forces at the distal surface of the stone. Comparing responses from four different stone types suggests that cystine is the most difficult stone to fragment in ESWL, as observed from clinical experience.

  18. Proton microprobe study of tin-polymetallic deposits

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S [Geological Survey of Japan, Tsukuba, Ibaraki (Japan); Sie, S H; Suter, G F [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

    1997-12-31

    Tin-polymetallic vein type deposits are a complex mixture of cassiterite and sulfides and they are the main source of technologically important rare metals such as indium and bismuth. Constituent minerals are usually fine grained having wide range of chemical composition and often the elements of interest occur as trace elements not amenable to electron microprobe analysis. PIXE with a proton microprobe can be an effective tool to study such deposits by delineating the distribution of trace elements among carrier minerals. Two representative indium-bearing deposits of tin- polymetallic type, Tosham of India (Cu-ln-Bi-Sn-W-Ag), and Mount Pleasant of Canada (Zn-Cu-In-Bi-Sn-W), were studied to delineate the distribution of medical/high-tech rare metals and to examine the effectiveness of the proton probe analysis of such ore. One of the results of the study indicated that indium and bismuth are present in chalcopyrite in the deposits. In addition to these important rare metals, zinc, copper, arsenic, antimony, selenium, and tin are common in chalcopyrite and pyrite. Arsenopyrite contains nickel, copper, zinc, silver, tin, antimony and bismuth. In chalcopyrite and pyrite, zinc, arsenic, indium, bismuth and lead are richer in Mount Pleasant ore, but silver is higher at Tosham. Also thallium and gold were found only in Tosham pyrite. The Tosham deposit is related to S-type granite, while Mount Pleasant to A-type. It appears that petrographic character of the source magma is one of the factors to determine the trace element distribution in tin-polymetallic deposit. 6 refs., 2 figs.

  19. Proton microprobe study of tin-polymetallic deposits

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S. [Geological Survey of Japan, Tsukuba, Ibaraki (Japan); Sie, S.H.; Suter, G.F. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

    1996-12-31

    Tin-polymetallic vein type deposits are a complex mixture of cassiterite and sulfides and they are the main source of technologically important rare metals such as indium and bismuth. Constituent minerals are usually fine grained having wide range of chemical composition and often the elements of interest occur as trace elements not amenable to electron microprobe analysis. PIXE with a proton microprobe can be an effective tool to study such deposits by delineating the distribution of trace elements among carrier minerals. Two representative indium-bearing deposits of tin- polymetallic type, Tosham of India (Cu-ln-Bi-Sn-W-Ag), and Mount Pleasant of Canada (Zn-Cu-In-Bi-Sn-W), were studied to delineate the distribution of medical/high-tech rare metals and to examine the effectiveness of the proton probe analysis of such ore. One of the results of the study indicated that indium and bismuth are present in chalcopyrite in the deposits. In addition to these important rare metals, zinc, copper, arsenic, antimony, selenium, and tin are common in chalcopyrite and pyrite. Arsenopyrite contains nickel, copper, zinc, silver, tin, antimony and bismuth. In chalcopyrite and pyrite, zinc, arsenic, indium, bismuth and lead are richer in Mount Pleasant ore, but silver is higher at Tosham. Also thallium and gold were found only in Tosham pyrite. The Tosham deposit is related to S-type granite, while Mount Pleasant to A-type. It appears that petrographic character of the source magma is one of the factors to determine the trace element distribution in tin-polymetallic deposit. 6 refs., 2 figs.

  20. Proton microprobe study of tin-polymetallic deposits

    International Nuclear Information System (INIS)

    Murao, S.; Sie, S.H.; Suter, G.F.

    1996-01-01

    Tin-polymetallic vein type deposits are a complex mixture of cassiterite and sulfides and they are the main source of technologically important rare metals such as indium and bismuth. Constituent minerals are usually fine grained having wide range of chemical composition and often the elements of interest occur as trace elements not amenable to electron microprobe analysis. PIXE with a proton microprobe can be an effective tool to study such deposits by delineating the distribution of trace elements among carrier minerals. Two representative indium-bearing deposits of tin- polymetallic type, Tosham of India (Cu-ln-Bi-Sn-W-Ag), and Mount Pleasant of Canada (Zn-Cu-In-Bi-Sn-W), were studied to delineate the distribution of medical/high-tech rare metals and to examine the effectiveness of the proton probe analysis of such ore. One of the results of the study indicated that indium and bismuth are present in chalcopyrite in the deposits. In addition to these important rare metals, zinc, copper, arsenic, antimony, selenium, and tin are common in chalcopyrite and pyrite. Arsenopyrite contains nickel, copper, zinc, silver, tin, antimony and bismuth. In chalcopyrite and pyrite, zinc, arsenic, indium, bismuth and lead are richer in Mount Pleasant ore, but silver is higher at Tosham. Also thallium and gold were found only in Tosham pyrite. The Tosham deposit is related to S-type granite, while Mount Pleasant to A-type. It appears that petrographic character of the source magma is one of the factors to determine the trace element distribution in tin-polymetallic deposit. 6 refs., 2 figs

  1. Morphology and phase transformations of tin oxide nanostructures synthesized by the hydrothermal method in the presence of dicarboxylic acids

    International Nuclear Information System (INIS)

    Zima, Tatyana; Bataev, Ivan

    2016-01-01

    A new approach to the synthesis of non-stoichiometric tin oxide structures with different morphologies and the phase compositions has been evaluated. The nanostructures were synthesized by hydrothermal treatment of the mixtures of dicarboxylic acids ― aminoterephthalic or oxalic ― with nanocrystalline SnO 2 powder, which was obtained via the sol-gel technology. The products were characterized by Raman and IR spectroscopy, SEM, HRTEM, and XRD analysis. It was shown that the controlled addition of a dicarboxylic acid leads not only to a change in the morphology of the nanostructures, but also to SnO 2 –SnO 2 /Sn 3 O 4 –Sn 3 O 4 –SnO phase transformations. A single-phase Sn 3 O 4 in the form of the well-separated hexagonal nanoplates and mixed SnO 2 /Sn 3 O 4 phases in the form of hierarchical flower-like structures were obtained in the presence of organic additives. The effects of concentration, redox activity of the acids and heat treatment on the basic characteristics of the synthesized tin oxide nanostructures and phase transformations in the synthesized materials are discussed. - Graphical abstract: The controlled addition of aminoterephthalic or oxalic acid leads not only to a change in the morphology of the nanostructures, but also to SnO 2 –SnO 2 /Sn 3 O 4 –Sn 3 O 4 –SnO phase transformations. - Highlights: • A new approach to the synthesis of non-stoichiometric tin oxide structures is studied. • Tin oxide structures are synthesized via hydrothermal method with dicarboxylic acids. • Morphology and phase composition are changed with redox activity and dosage of acid. • The redox activity of acid has an effect on ratio of SnO and SnO 2 in crystal structure. • A pure phase Sn 3 O 4 nanoplates and SnO 2 /Sn 3 O 4 hierarchical structures are formed.

  2. Advanced Computational Modeling Approaches for Shock Response Prediction

    Science.gov (United States)

    Derkevorkian, Armen; Kolaini, Ali R.; Peterson, Lee

    2015-01-01

    Motivation: (1) The activation of pyroshock devices such as explosives, separation nuts, pin-pullers, etc. produces high frequency transient structural response, typically from few tens of Hz to several hundreds of kHz. (2) Lack of reliable analytical tools makes the prediction of appropriate design and qualification test levels a challenge. (3) In the past few decades, several attempts have been made to develop methodologies that predict the structural responses to shock environments. (4) Currently, there is no validated approach that is viable to predict shock environments overt the full frequency range (i.e., 100 Hz to 10 kHz). Scope: (1) Model, analyze, and interpret space structural systems with complex interfaces and discontinuities, subjected to shock loads. (2) Assess the viability of a suite of numerical tools to simulate transient, non-linear solid mechanics and structural dynamics problems, such as shock wave propagation.

  3. Tin and tin-titanium as catalyst components for reversible hydrogen storage of sodium aluminium hydride

    Energy Technology Data Exchange (ETDEWEB)

    Qi Jia Fu; Shik Chi Tsang [University of Reading, Reading (United Kingdom). Surface and Catalysis Research Centre, School of Chemistry

    2006-10-15

    This paper is concerned with the effects of adding tin and/or titanium dopant to sodium aluminium hydride for both dehydrogenation and re-hydrogenation reactions during their reversible storage of molecular hydrogen. Temperature programmed decomposition (TPD) measurements show that the dehydrogenation kinetics of NaAlH{sub 4} are significantly enhanced upon doping the material with 2 mol% of tributyltin hydride, Sn(Bu)3H but the tin catalyst dopant is shown to be inferior than titanium. On the other hand, in this preliminary work, a significant synergetic catalytic effect is clearly revealed in material co-doped with both titanium and tin catalysts which shows the highest reversible rates of dehydrogenation and re-hydrogenation (after their hydrogen depletion). The re-hydrogenation rates of depleted Sn/Ti/NaAlH{sub 4} evaluated at both 9.5 and 140 bars hydrogen are also found to be favourable compared to the Ti/NaAlH{sub 4}, which clearly suggest the importance of the catalyst choice. Basing on these results some mechanistic insights for the catalytic reversible dehydrogenation and re-hydrogenation processes of Sn/Ti/NaAlH{sub 4} are therefore made. 31 refs., 8 figs., 2 tabs.

  4. Spectroscopic and luminescent properties of Co2+ doped tin oxide thin films by spray pyrolysis

    Directory of Open Access Journals (Sweden)

    K. Durga Venkata Prasad

    2016-07-01

    Full Text Available The wide variety of electronic and chemical properties of metal oxides makes them exciting materials for basic research and for technological applications alike. Oxides span a wide range of electrical properties from wide band-gap insulators to metallic and superconducting. Tin oxide belongs to a class of materials called Transparent Conducting Oxides (TCO which constitutes an important component for optoelectronic applications. Co2+ doped tin oxide thin films were prepared by chemical spray pyrolysis synthesis and characterized by powder X-ray diffraction, SEM, TEM, FT-IR, optical, EPR and PL techniques to collect the information about the crystal structure, coordination/local site symmetry of doped Co2+ ions in the host lattice and the luminescent properties of the prepared sample. Powder XRD data revealed that the crystal structure belongs to tetragonal rutile phase and its lattice cell parameters are evaluated. The average crystallite size was estimated to be 26 nm. The morphology of prepared sample was analyzed by using SEM and TEM studies. Functional groups of the prepared sample were observed in the FT-IR spectrum. Optical absorption and EPR studies have shown that on doping, Co2+ ions enter in the host lattice as octahedral site symmetry. PL studies of Co2+ doped SnO2 thin films exhibit blue and yellow emission bands. CIE chromaticity coordinates were also calculated from emission spectrum of Co2+ doped SnO2 thin films.

  5. Laser shocks: A tool for experimental simulation of damage into materials

    Energy Technology Data Exchange (ETDEWEB)

    Boustie, M.; Cuq Lelandais, J. P.; Berthe, L.; Ecault, R. [Institut PPRIME, Departement Physique et Mecanique des Materiaux, CNRS-ENSMA-Universite de Poitiers, 1 av Clement Ader, 86961 FUTUROSCOPE Cedex (France); CEA-DAM Valduc, 21120 Is-sur-Tille (France); Laboratoire Procedes et Ingenierie en Mecanique et Materiaux (CNRS), Arts et Metiers ParisTech, 151 bd de l' Hopital, 75013 PARIS (France); Institut PPRIME, Departement Physique et Mecanique des Materiaux, CNRS-ENSMA-Universite de Poitiers, 1 av Clement Ader, 86961 FUTUROSCOPE Cedex (France)

    2012-07-30

    High power laser irradiation of solids results in a strong shock wave propagation, driving very high amplitude pressure loadings with very short durations. These particular characteristics offer the possibility to study the behaviour of matter under extreme dynamic conditions in continuity with what is possible with the conventional generators of shock (launchers of projectiles, explosives). An advantage of laser shocks is a possible recovery of the shocked samples presenting the metallurgical effects of the shock in most cases. We introduce the principle of the laser shock generation, the characterization of these shocks, the principal mechanisms and effects associated with their propagation in the solids. We show how laser shocks can be a laboratory tool for simulating shock effects at ultra high strain rate, providing a high in information experimental layout for validation of damage modelling on an extended strain rate range compared to conventional shock generators. New data have been obtained with ultra short femtosecond range irradiation. Experimental data gathered through post mortem observation, time resolved velocity measurement are shown along with numerical associated simulations, showing the possibility to predict the damage behaviour of metallic targets under extreme strain rate up to 10{sup 8} s{sup -1}.

  6. Some recent advances of shock wave physics research at the Laboratory for Shock Wave and Detonation Physics Research

    CERN Document Server

    Jing Fu Qian

    2002-01-01

    Progress made in recent years on three topics that have been investigated at the Laboratory for Shock Wave and Detonation Physics Research are presented in this report. (1) A new equation of state (EOS) has been derived which can be used from a standard state to predict state variable change along an isobaric path. Good agreements between calculations for some representative metals using this new EOS and experiments have been found, covering a wide range from hundreds of MPa to hundreds of GPa and from ambient temperature to tens of thousands of GPa. (2) An empirical relation of Y/G = constant (Y is yield strength, G is shear modulus) at HT-HP has been reinvestigated and confirmed by shock wave experiment. 93W alloy was chosen as a model material. The advantage of this relation is that it is beneficial to formulate a kind of simplified constitutive equation for metallic solids under shock loading, and thus to faithfully describe the behaviours of shocked solids through hydrodynamic simulations. (3) An attempt...

  7. Laser micromachining of indium tin oxide films on polymer substrates by laser-induced delamination

    International Nuclear Information System (INIS)

    Willis, David A; Dreier, Adam L

    2009-01-01

    A Q-switched neodymium : yttrium-aluminium-garnet (Nd : YAG) laser was used to ablate indium tin oxide (ITO) thin films from polyethylene terephthalate substrates. Film damage and partial removal with no evidence of a melt zone was observed above 1.7 J cm -2 . Above the film removal threshold (3.3 J cm -2 ) the entire film thickness was removed without substrate damage, suggesting that ablation was a result of delamination of the film in the solid phase. Measurements of ablated fragment velocities near the ablation threshold were consistent with calculations of velocities caused by stress-induced delamination of the ITO film, except for a high velocity component at higher fluences. Nanosecond time-resolved shadowgraph photography revealed that the high velocity component was a shock wave induced by the rapid compression of ambient air when the film delaminated.

  8. Shock-induced thermal wave propagation and response analysis of a viscoelastic thin plate under transient heating loads

    Science.gov (United States)

    Li, Chenlin; Guo, Huili; Tian, Xiaogeng

    2018-04-01

    This paper is devoted to the thermal shock analysis for viscoelastic materials under transient heating loads. The governing coupled equations with time-delay parameter and nonlocal scale parameter are derived based on the generalized thermo-viscoelasticity theory. The problem of a thin plate composed of viscoelastic material, subjected to a sudden temperature rise at the boundary plane, is solved by employing Laplace transformation techniques. The transient responses, i.e. temperature, displacement, stresses, heat flux as well as strain, are obtained and discussed. The effects of time-delay and nonlocal scale parameter on the transient responses are analyzed and discussed. It can be observed that: the propagation of thermal wave is dynamically smoothed and changed with the variation of time-delay; while the displacement, strain, and stress can be rapidly reduced by nonlocal scale parameter, which can be viewed as an important indicator for predicting the stiffness softening behavior for viscoelastic materials.

  9. Meso-scale modelling of the heat conductivity effect on the shock response of a porous material

    Science.gov (United States)

    Resnyansky, A. D.

    2017-06-01

    Understanding of deformation mechanisms of porous materials under shock compression is important for tailoring material properties at the shock manufacturing of advanced materials from substrate powders and for studying the response of porous materials under shock loading. Numerical set-up of the present work considers a set of solid particles separated by air representing a volume of porous material. Condensed material in the meso-scale set-up is simulated with a viscoelastic rate sensitive material model with heat conduction formulated from the principles of irreversible thermodynamics. The model is implemented in the CTH shock physics code. The meso-scale CTH simulation of the shock loading of the representative volume reveals the mechanism of pore collapse and shows in detail the transition from a high porosity case typical for abnormal Hugoniot response to a moderate porosity case typical for conventional Hugoniot response. Results of the analysis agree with previous analytical considerations and support hypotheses used in the two-phase approach.

  10. Characterisation of bare and tannase-loaded calcium alginate beads by microscopic, thermogravimetric, FTIR and XRD analyses.

    Science.gov (United States)

    Larosa, Claudio; Salerno, Marco; de Lima, Juliana Silva; Merijs Meri, Remo; da Silva, Milena Fernandes; de Carvalho, Luiz Bezerra; Converti, Attilio

    2018-08-01

    Incorporating enzymes into calcium alginate beads is an effective method to immobilise them and to preserve, at the same time, their catalytic activity. Sodium alginate was mixed with Aspergillus ficuum tannase in aqueous solution, and tannase-loaded calcium alginate beads were prepared using a simple droplet-based microfluidic system. Extensive experimental analysis was carried out to characterise the samples. Microscopic imaging revealed morphological differences between the surfaces of bare alginate matrix and tannase-loaded alginate beads. Thermal analysis allowed assessing the hydration contents of alginate and revealed the presence of tannase entrapped in the loaded beads, which was confirmed by vibrational spectroscopy. X-ray diffraction allowed us to conclude that alginate of tannase-loaded beads is not crystalline, which would make them suitable as carriers for possible controlled release. Moreover, they could be used in food applications to improve tea quality or clarify juices. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Electrodeposition, characterization and corrosion investigations of galvanic tin-zinc layers from pyrophosphate baths

    OpenAIRE

    STOPIC MILENA D.; FRIEDRICH BERND G.

    2016-01-01

    Tin-zinc alloy deposits are recognized as a potential alternative to toxic cadmium as corrosion resistant coatings. Tin-zinc alloy layers offer outstanding corrosion protection for steel by combining the barrier protection of tin with the galvanic protection of zinc. Tin-zinc coatings have been used on the chassis of electrical and electronic apparatus and on critical automotive parts such as fuel and brake line components. In this study, tin-zinc alloy deposits were successfully prepared fro...

  12. Determination of tin in cassiterite ores by colorimetry of iodometry

    International Nuclear Information System (INIS)

    Rodriguez Hernandez, B.

    1972-01-01

    The analytical methods are described far the determination of tin in cassiterite ores. The gallein-colorimetric method is described for determining small amounts of tin, covering the 0,01-0,5 per cent range. The sample is decomposed by heating with ammonium iodide, and tin is analyzed colorimetrically by means of it s complex with gallein. The final measure may be brought about either visually or spectrophotometrically at 525 nm. (Author)

  13. Role of different chelating agent in synthesis of copper doped tin oxide (Cu-SnO2) nanoparticles

    Science.gov (United States)

    Saravanakumar, B.; Anusiya, A.; Rani, B. Jansi; Ravi, G.; Yuvakkumar, R.

    2018-05-01

    An attempt was made to synthesis the copper doped tin oxide (Cu-SnO2) nanoparticles by adopting different chelating agents (NaOH, KOH and C2H2O4) by Sol-gel process. The synthesized products were characterized by XRD, Photoluminescence (PL), Infra- Red (FTIR) and SEM analysis. The XRD confirms the formation of Cu-SnO2 shows the maximum peak at 33.8° with lattice plane (101). The PL peak at 361 and 382 nm due to the recombination of electron in conduction band to valence band infers the optical properties. The IR spectra correspond to the peak at 551 and 620 cm-1 attributed to the characteristics peak for Cu-SnO2 nanoparticles. The SEM images for all three Cu-SnO2 nanoparticles formed by three chelating agent (NaOH, KOH and C2H2O4) facilitates the formation mechanism and the chelating agent Oxalic acid results in formation of nano flowers with diverse layers orientated in random direction. Further SEM studies reveal that, the Cu-SnO2 nanoparticles formed by oxalic acid could posses high surface area with large number layered structured enables the better electrochemical properties and its applications.

  14. Martensitic transformations in titanium nickelide subject to sock wave loading

    International Nuclear Information System (INIS)

    Zel'dovich, V.I.; Shorokhov, E.V.; Gundyrev, V.M.; Khejfets, A.Eh.; Frolova, N.Yu.; Khomskaya, I.V.

    2000-01-01

    The plates of titanium nickelide (Ti-50.5 at. % Ni) rolled in an austenitic state and subjected to impact shock with pressure of 10 and 50 GPa are under study. Dilatometric and X-ray diffraction studied show that shock wave loading induces anisotropic martensitic transformations in the plates. The anisotropy of transformations is conditioned by directed motion of the substance of the plate in shock waves. Austenitic memory of specimens prior to loading is changed to martensitic one typical of deformation of martensite. Martensitic memory not preserve after the reserve martensitic transformation, the specimens recall the initial state with austenitic memory. The particles of Ti 3 N 4 precipitated phase and the dislocation structure formed in rolling are the carriers of memory [ru

  15. Synthesize of Graphene-Tin Oxide Nanocomposite and Its Photocatalytic Properties for the Degradation of Organic Pollutants Under Visible Light.

    Science.gov (United States)

    Shanmugam, M; Jayavel, R

    2015-09-01

    Graphene-tinoxide nanocomposite has been synthesised by coating SnO2 nanoparticles on graphene sheets by the redox reaction between graphene oxide (GO) and tin chloride. Graphene oxide was reduced to graphene and Sn2+ was oxidized to SnO2 during the redox reaction, resulting in the uniform distribution of SnO2 nanoparticles on graphene sheets. The synthesised material was characterized by XRD, SEM, AFM, FT-IR, UV-vis, TGA and Raman spectroscopic studies. SEM and AFM studies reveal the formation of wrinkled paper like structure of graphene sheets with uniform coating of SnO2 nanoparticles on either side. The strong photocatalytic degradation of Methylene orange (MO) dye was analysed using G-SnO2 nanocomposite under the visible light irradiation.

  16. The influence of peak shock stress on the high pressure phase transformation in Zr

    International Nuclear Information System (INIS)

    Cerreta, E K; Addessio, F L; Bronkhorst, C A; Brown, D W; Escobedo, J P; Fensin, S J; Gray, G T III; Lookman, T; Rigg, P A; Trujillo, C P

    2014-01-01

    At high pressures zirconium is known to undergo a phase transformation from the hexagonal close packed (HCP) alpha phase to the simple hexagonal omega phase. Under conditions of shock loading, a significant volume fraction of high-pressure omega phase is retained upon release. However, the hysteresis in this transformation is not well represented by equilibrium phase diagrams and the multi-phase plasticity under shock conditions is not well understood. For these reasons, the influence of peak shock stress and temperature on the retention of omega phase in Zr has been explored. VISAR and PDV measurements along with post-mortem metallographic and neutron diffraction characterization of soft recovered specimens have been utilized to quantify the volume fraction of retained omega phase and qualitatively understand the kinetics of this transformation. In turn, soft recovered specimens with varying volume fractions of retained omega phase have been utilized to understand the contribution of omega and alpha phases to strength in shock loaded Zr.

  17. Shock and vibration environments for a large shipping container during truck transport (Part II)

    International Nuclear Information System (INIS)

    Magnuson, C.E.

    1978-05-01

    Purpose of this study was to obtain vibration and shock data during truck shipment of heavy cargo. These data were for use in determining any trends of vibration and shock environments with increased cargo weight. The new data were obtained on a ''piggyback'' basis during truck transport of 249 100N (56,000-pound) cargo which consisted of a spent fuel container and its supporting structure. The truck was driven from Mercury, Nevada, to Albuquerque, New Mexico. The routes traveled were US 95 from Mercury, Nevada, to Las Vegas, Nevada; US 93 from Las Vegas to Kingman, Arizona; and I-40/US 66 from Kingman to Albuquerque, New Mexico. Speeds varied from very slow to 88 km/hr (55 mph). A comparison of data from similar experiments with cargo weights varying from no-load to this load shows that the zero-to-peak acceleration amplitude levels of vibration are highest when trucks carry relatively light loads. This is true for the longitudinal and vertical axes of the vehicles in most frequency bands and for the transverse axis above 700 Hz. The shock response acceleration amplitudes for heavier cargo weights were less severe above 3 Hz in the vertical axis and higher between 8 and 20 Hz in the transverse axis. The highest acceleration amplitude of shock response in the longitudinal axis below about 20 Hz was produced in a trailer having a spring suspension system and carrying the 249 100N (56,000 pounds) load

  18. Behavior of deep flaws in a thick-wall cylinder under thermal shock loading

    International Nuclear Information System (INIS)

    Cheverton, R.D.

    1979-01-01

    Behavior of inner-surface flaws in thick-walled vessels was studied in a 991-mm OD x 152 mm wall x 1220 mm length cylinder with toughness properties similar to those for HSST Plate. The initial temperature of 93 0 C and a thermal shock medium of liquid nitrogen (-197 0 C) were employed. The initial flaw selected was a sharp, 16 mm deep, long (1220 mm) axial crack. Crack arrest methodology was shown to be valid for deep flaws under severe thermal shock

  19. Performance of multifilamentary Nb3Sn under mechanical load

    International Nuclear Information System (INIS)

    Easton, D.S.; Schwall, R.E.

    1976-01-01

    The critical current of a commercial multifilamentary Nb 3 Sn conductor has been measured under the application of uniaxial tension at 4.2 K and following bending at room temperature. Significant reductions in J/subc/ are observed under uniaxial loading. Results are presented for a monolithic conductor manufactured by the bronze diffusion technique and for cable conductors formed by the tin-dip technique

  20. The recovery of tin, and the production of niobium pentoxide and potassium tantalum fluoride, from a tin slag

    International Nuclear Information System (INIS)

    Iorio, G.; Tyler, M.S.

    1987-01-01

    This report describes the results of testwork on the recovery of tin, niobium, and tantalum from a tin slag. The slag, which consisted mainly of amorphous silica, with varying amounts of calcuim, magnesium, manganese, iron, and aluminium, contained an average of 8,8 per cent niobium pentoxide and 6,2 per cent tantalum pentoxide. The metallic tin-ion phase was removed from the crushed slag by magnetic separation. The slag was then leached with hydrochloric acid to remove magnesium, calcium, aluminium, iron, manganese, and the remainder of the tin. Leaching with sodium hydroxide for the removal of silica and phosphorous was followed by a final leach with hydrochloric acid for the removal of sodium. The upgraded concentrate thus obtained was purified by leaching with hydrofluoric acid, solvent extraction of niobium and tantalum into tri-n-butyl phosphate and methyl isobutyl ketone, and selective stripping of niobium with sulphuric acid and tantalum with ammonium floride. Niobium pentoxide and potassium tantalum fluoride were then precipitated by the addition of ammonium hydroxide and potassium fluoride to the respective strip liquors. The overall recoveries in the upgraded concentrate were 98 per cent for tantalum and 92 per cent for niobium. Dissolutions and recoveries of over 99 per cent were obtained for both tantalum and niobium in the purification steps. The niobium pentoxide and potassium tantalum fluoride precipitates obtained were of high purity

  1. Shock Initiation of Damaged Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; Vandersall, K S; Tarver, C M

    2009-10-22

    Explosive and propellant charges are subjected to various mechanical and thermal insults that can increase their sensitivity over the course of their lifetimes. To quantify this effect, shock initiation experiments were performed on mechanically and thermally damaged LX-04 (85% HMX, 15% Viton by weight) and PBX 9502 (95% TATB, 5% Kel-F by weight) to obtain in-situ manganin pressure gauge data and run distances to detonation at various shock pressures. We report the behavior of the HMX-based explosive LX-04 that was damaged mechanically by applying a compressive load of 600 psi for 20,000 cycles, thus creating many small narrow cracks, or by cutting wedge shaped parts that were then loosely reassembled, thus creating a few large cracks. The thermally damaged LX-04 charges were heated to 190 C for long enough for the beta to delta solid - solid phase transition to occur, and then cooled to ambient temperature. Mechanically damaged LX-04 exhibited only slightly increased shock sensitivity, while thermally damaged LX-04 was much more shock sensitive. Similarly, the insensitive explosive PBX 9502 was mechanically damaged using the same two techniques. Since PBX 9502 does not undergo a solid - solid phase transition but does undergo irreversible or 'rachet' growth when thermally cycled, thermal damage to PBX 9502 was induced by this procedure. As for LX-04, the thermally damaged PBX 9502 demonstrated a greater shock sensitivity than mechanically damaged PBX 9502. The Ignition and Growth reactive flow model calculated the increased sensitivities by igniting more damaged LX-04 and PBX 9502 near the shock front based on the measured densities (porosities) of the damaged charges.

  2. Studies on tin based inorganic ion exchangers for fission products separation

    International Nuclear Information System (INIS)

    Dash, A.; Balasubramanian, K.R.; Murthy, T.S.

    1993-01-01

    Tin(IV) antimonate and hydrous tin(IV) oxide have been prepared and their characteristics are evaluated. A new method has been finalized for the separation of 95 Zr- 95 Nb from irradiated uranium using hydrous tin(IV) oxide. In this process, the irradiated sample is dissolved in concentrated HNO 3 , evaporated to near dryness and taken up in 0.5 M HNO 3 . The solution is passed over tin(IV) oxide column and the isotope eluted with 10 M HNO 3 . The product is obtained in pure nitrate form which is generally preferred for different applications. A method has been finalized for the separation of 106 Ru from fission product solution using tin(IV) antimonate. In this method fission product solution is adjusted to 2 M with respect to nitric acid, 137 Cs is separated on a column of ammonium phosphomolybdate, the effluent after adjustment of acidity to 0.2 M is then passed over a column of tin(IV) antimonate where the effluent contains pure 106 Ru. (author). 14 refs., 6 figs., 2 tabs

  3. DETERMINATION OF ENERGY LOSSES BY SHOCK ABSORBER IN A FREIGHT CAR AT CRASH MODE

    Directory of Open Access Journals (Sweden)

    Ya. V. Bolzhelarskyi

    2016-08-01

    Full Text Available Purpose. The purpose of this work is to determine the energy losses in the shock absorber of the freight car whose wheel-set moves in the derailed state on the track panel depending on the axle load and structural parameters of spring suspension. Methodology. On the basis of spring suspension construction analysis and operating principle of the friction shock absorber of the freight car bogie the authors provide the method for determining the energy absorbed by it. The calculations take the maximum values of the absorber elements displacement and the regulatory values of spring suspension parameters. Findings. The authors obtained the calculated formula for determining the energy absorbed by shock absorber for regulation-set mounting schemes of elastic bogie elements depending on the axial load. The mentioned curves are parabolic. Originality. The work examines the crash mode of the wheel-set movement on the track panels after its derailment. It is shown that the energy dissipation in the shock absorbers is the reason for increase in resistance to rolling stock movement. The formulas for calculating the amount of energy dissipated in the shock absorber with a maximum displacement of its elements are derived. This energy depends on the axle load and structural parameters of spring suspension. Practical value. The proposed method allows setting the value of the additional resistance to motion that occurs in crash mode which makes it possible to increase the accuracy of traction calculations.

  4. Advances in ferroelectric polymers for shock compression sensors

    International Nuclear Information System (INIS)

    Bauer, F.; Moulard, H.; Samara, G.

    1997-01-01

    Our studies of the shock compression response of PVDF polymer are continuing in order to understand the physical properties under shock loading and to develop high fidelity, reproducible, time-resolved dynamic stress gauges. New PVDF technology, new electrode configurations and piezoelectric analysis have resulted in enhanced precision gauges. Our new standard gauges have a precision of better than 1% in electric charge release under shock up to 15 GPa. The piezoelectric response of shock compressed PVDF gauges 1 mm 2 in active area has been studied and yielded well-behaved reproducible data up to 20 GPa. Analysis of the response of these gauges in the open-quotes thin mode regimeclose quotes using a Lagrangian hydrocode will be presented. P(VDF-TrFE) copolymers exhibit unique piezoelectric properties over a wide range of temperature depending on the composition. Their properties and phase transitions are being investigated. Emphasis of the presentation will be on key results and implications

  5. Shock waves in water at low energy pulsed electric discharges

    International Nuclear Information System (INIS)

    Pinchuk, M E; Kolikov, V A; Rutberg, Ph G; Leks, A G; Dolinovskaya, R V; Snetov, V N; Stogov, A Yu

    2012-01-01

    Experimental results of shock wave formation and propagation in water at low energy pulsed electric discharges are presented. To study the hydrodynamic structure of the shock waves, the direct shadow optical diagnostic device with time resolution of 5 ns and spatial resolution of 0.1 mm was designed and developed. Synchronization of the diagnostic and electrodischarge units by the fast optocouplers was carried out. The dependences of shock wave velocities after breakdown of interelectrode gap for various energy inputs (at range of ≤1 J) into discharge were obtained. Based on the experimental results the recommendations for the adjustment parameters of the power supply and load were suggested.

  6. The Moessbauer effect in binary tin chalcogenides of tin 119

    International Nuclear Information System (INIS)

    Ortalli, I.; Fano, V.

    1975-01-01

    The values of the isomer shift, quadrupole splitting, Moessbauer coefficient, Debye temperature for the tin chalcogenides SnS. SnSe, SnTe are tabulated for the temperatures 80 and 300 K. Temperature dependences of the Moessbauer coefficient and of the effective Debye temperature for SnS, SnSe and SnTe in a temperature range of 78 to 300 K are presented. (Z.S.)

  7. Research into tin and arsenical copper artefacts using nuclear analytical techniques

    International Nuclear Information System (INIS)

    Grant, M.R.

    1995-01-01

    This study includes the chemical analysis, sourcing and historical metallurgy of tin and arsenical copper artefacts discovered at Rooiberg and elsewhere in the Northern Transvaal and at Great Zimbabwe. A complete chemical analysis method for tin and cassiterite is presented, based on INAA (instrumental neutron activation analysis) and supplemented by PIXE or AAS for elements such as lead, bismuth and niobium. This is apparently the first study in which tin artefacts were analysed by INAA without chemical processing of the samples. INAA and PIXE returned the same results when a homogenized tin alloy block was analysed, but the structure and distribution of hardhead phases appear to produce an iron quantification problem in ancient tin. Ores and slags were analysed for light matrix elements by XRF or PIXE and INAA for the heavy trace metals. 108 refs., 24 figs., 130 tabs

  8. Estimating the Probability of Electrical Short Circuits from Tin Whiskers. Part 2

    Science.gov (United States)

    Courey, Karim J.; Asfour, Shihab S.; Onar, Arzu; Bayliss, Jon A.; Ludwig, Larry L.; Wright, Maria C.

    2010-01-01

    To comply with lead-free legislation, many manufacturers have converted from tin-lead to pure tin finishes of electronic components. However, pure tin finishes have a greater propensity to grow tin whiskers than tin-lead finishes. Since tin whiskers present an electrical short circuit hazard in electronic components, simulations have been developed to quantify the risk of said short circuits occurring. Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that had an unknown probability associated with it. Note however that due to contact resistance electrical shorts may not occur at lower voltage levels. In our first article we developed an empirical probability model for tin whisker shorting. In this paper, we develop a more comprehensive empirical model using a refined experiment with a larger sample size, in which we studied the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From the resulting data we estimated the probability distribution of an electrical short, as a function of voltage. In addition, the unexpected polycrystalline structure seen in the focused ion beam (FIB) cross section in the first experiment was confirmed in this experiment using transmission electron microscopy (TEM). The FIB was also used to cross section two card guides to facilitate the measurement of the grain size of each card guide's tin plating to determine its finish .

  9. Synthesis, characterization and photoluminescence of tin oxide nanoribbons and nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Duraia, El-Shazly M.A., E-mail: duraia_physics@yahoo.co [Suez Canal University, Faculty of Science, Physics Department, Ismailia (Egypt); Al-Farabi Kazakh National University, Almaty (Kazakhstan); Institute of Physics and Technology, 11 Ibragimov Street, 050032 Almaty (Kazakhstan); Mansorov, Z.A. [Al-Farabi Kazakh National University, Almaty (Kazakhstan); Tokmolden, S. [Institute of Physics and Technology, 11 Ibragimov Street, 050032 Almaty (Kazakhstan)

    2009-11-15

    In this work we report the successful formation of tin oxide nanowires and tin oxide nanoribbons with high yield and by using simple cheap method. We also report the formation of curved nanoribbon, wedge-like tin oxide nanowires and star-like nanowires. The growth mechanism of these structures has been studied. Scanning electron microscope was used in the analysis and the EDX analysis showed that our samples is purely Sn and O with ratio 1:2. X-ray analysis was also used in the characterization of the tin oxide nanowire and showed the high crystallinity of our nanowires. The mechanism of the growth of our1D nanostructures is closely related to the vapor-liquid-solid (VLS) process. The photoluminescence PL measurements for the tin oxide nanowires indicated that there are three stable emission peaks centered at wavelengths 630, 565 and 395 nm. The nature of the transition may be attributed to nanocrystals inside the nanobelts or to Sn or O vacancies occurring during the growth which can induce trapped states in the band gap.

  10. Carbothermal shock synthesis of high-entropy-alloy nanoparticles

    Science.gov (United States)

    Yao, Yonggang; Huang, Zhennan; Xie, Pengfei; Lacey, Steven D.; Jacob, Rohit Jiji; Xie, Hua; Chen, Fengjuan; Nie, Anmin; Pu, Tiancheng; Rehwoldt, Miles; Yu, Daiwei; Zachariah, Michael R.; Wang, Chao; Shahbazian-Yassar, Reza; Li, Ju; Hu, Liangbing

    2018-03-01

    The controllable incorporation of multiple immiscible elements into a single nanoparticle merits untold scientific and technological potential, yet remains a challenge using conventional synthetic techniques. We present a general route for alloying up to eight dissimilar elements into single-phase solid-solution nanoparticles, referred to as high-entropy-alloy nanoparticles (HEA-NPs), by thermally shocking precursor metal salt mixtures loaded onto carbon supports [temperature ~2000 kelvin (K), 55-millisecond duration, rate of ~105 K per second]. We synthesized a wide range of multicomponent nanoparticles with a desired chemistry (composition), size, and phase (solid solution, phase-separated) by controlling the carbothermal shock (CTS) parameters (substrate, temperature, shock duration, and heating/cooling rate). To prove utility, we synthesized quinary HEA-NPs as ammonia oxidation catalysts with ~100% conversion and >99% nitrogen oxide selectivity over prolonged operations.

  11. Synthesis and Characterization of Tin (IV Tungstate Nanoparticles – A Solid Acid Catalyst

    Directory of Open Access Journals (Sweden)

    Manoj Sadanandan

    2012-12-01

    Full Text Available Tin (IV tungstate, a tetravalent metal acid salt was synthesized in the nanoform by chemical coprecipitation method using EDTA as capping agent. The material was found to be stable in mineral acids, bases and organic solvents except  in HF and aquaregia. The material was characterized using EDS, TG/DTA, FTIR, XRD, SEM, HRTEM and BET surface area measurement. The molecular formula of the compound is 2SnO2 3WO3.5H2O determined from elemental analysis using TG/DTA. Surface morphology and particle size were obtained using SEM and HRTEM. The surface area was found to be 205-225m2/g. The Na+ exchange capacity found to be 3.8 meq/g, indicates the presence of surface hydroxyl group and hence the presence of Bronsted acid sites. The catalytic activity of the material was tested by using esterification and oxidation as model reactions. For the esterification of different alcohols, the percentage yield was found to be high for n-alcohol compared to isomeric alcohols. Oxidation of benzyl alcohol gives benzaldehyde and benzoic acid as the only products. Copyright © 2012 by BCREC UNDIP. All rights reservedReceived: 12nd June 2012, Revised: 23rd July 2012, Accepted: 29th July 2012[How to Cite: S. Manoj, R. Beena, (2012. Synthesis and Characterization of tin(IV Tungstate Nanoparticles – A Solid Acid Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 7 (2: 105-111. doi:10.9767/bcrec.7.2.3622.105-111] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.3622.105-111 ] | View in 

  12. Influence of Microstructure on the Electrical Properties of Heteroepitaxial TiN Films

    Science.gov (United States)

    Xiang, Wenfeng; Liu, Yuan; Zhang, Jiaqi

    2018-03-01

    Heteroepitaxial TiN films were deposited on Si substrates by pulse laser deposition at different substrate temperature. The microstructure and surface morphology of the films were investigated by X-ray diffraction (θ-2θ scan, ω-scan, and ϕ-scan) and atomic force microscopy. The electrical properties of the prepared TiN films were studied using a physical property measurement system. The experimental results showed that the crystallinity and surface morphology of the TiN films were improved gradually with increasing substrate temperature below 700 °C. Specially, single crystal TiN films were prepared when substrate temperature is above 700 °C; However, the quality of TiN films gradually worsened when the substrate temperature was increased further. The electrical properties of the films were directly correlated to their crystalline quality. At the optimal substrate temperature of 700 °C, the TiN films exhibited the lowest resistivity and highest mobility of 25.7 μΩ cm and 36.1 cm2/V s, respectively. In addition, the mechanism concerning the influence of substrate temperature on the microstructure of TiN films is discussed in detail.

  13. Remote In-Situ Quantitative Mineralogical Analysis Using XRD/XRF

    Science.gov (United States)

    Blake, D. F.; Bish, D.; Vaniman, D.; Chipera, S.; Sarrazin, P.; Collins, S. A.; Elliott, S. T.

    2001-01-01

    X-Ray Diffraction (XRD) is the most direct and accurate method for determining mineralogy. The CHEMIN XRD/XRF instrument has shown promising results on a variety of mineral and rock samples. Additional information is contained in the original extended abstract.

  14. Mechanical Characterization of the Human Lumbar Intervertebral Disc Subjected to Impact Loading Conditions

    Science.gov (United States)

    Jamison, David, IV

    Low back pain is a large and costly problem in the United States. Several working populations, such as miners, construction workers, forklift operators, and military personnel, have an increased risk and prevalence of low back pain compared to the general population. This is due to exposure to repeated, transient impact shocks, particularly while operating vehicles or other machinery. These shocks typically do not cause acute injury, but rather lead to pain and injury over time. The major focus in low back pain is often the intervertebral disc, due to its role as the major primary load-bearing component along the spinal column. The formation of a reliable standard for human lumbar disc exposure to repeated transient shock could potentially reduce injury risk for these working populations. The objective of this project, therefore, is to characterize the mechanical response of the lumbar intervertebral disc subjected to sub-traumatic impact loading conditions using both cadaveric and computational models, and to investigate the possible implications of this type of loading environment for low back pain. Axial, compressive impact loading events on Naval high speed boats were simulated in the laboratory and applied to human cadaveric specimen. Disc stiffness was higher and hysteresis was lower than quasi-static loading conditions. This indicates a shift in mechanical response when the disc is under impact loads and this behavior could be contributing to long-term back pain. Interstitial fluid loss and disc height changes were shown to affect disc impact mechanics in a creep study. Neutral zone increased, while energy dissipation and low-strain region stiffness decreased. This suggests that the disc has greater clinical instability during impact loading with progressive creep and fluid loss, indicating that time of day should be considered for working populations subjected to impact loads. A finite element model was developed and validated against cadaver specimen

  15. Time-resolved diffraction of shock-released SiO2 and diaplectic glass formation

    International Nuclear Information System (INIS)

    Gleason, A. E.; Bolme, C. A.; Lee, H. J.; Nagler, B.

    2017-01-01

    Understanding how rock-forming minerals transform under shock loading is critical for modeling collisions between planetary bodies, interpreting the significance of shock features in minerals and for using them as diagnostic indicators of impact conditions, such as shock pressure. To date, our understanding of the formation processes experienced by shocked materials is based exclusively on ex situ analyses of recovered samples. Formation mechanisms and origins of commonly observed mesoscale material features, such as diaplectic (i.e., shocked) glass, remain therefore controversial and unresolvable. Here in this paper we show in situ pump-probe X-ray diffraction measurements on fused silica crystallizing to stishovite on shock compression and then converting to an amorphous phase on shock release in only 2.4 ns from 33.6 GPa. Recovered glass fragments suggest permanent densification. These observations of real-time diaplectic glass formation attest that it is a back-transformation product of stishovite with implications for revising traditional shock metamorphism stages.

  16. Electrochemical reduction of trinitrotoluene on core-shell tin-carbon electrodes

    International Nuclear Information System (INIS)

    Grigoriants, Irena; Markovsky, Boris; Persky, Rachel; Perelshtein, Ilana; Gedanken, Aharon; Aurbach, Doron; Filanovsky, Boris; Bourenko, Tatiana; Felner, Israel

    2008-01-01

    In this work, we studied the electrochemical process of 2,4,6-trinitrotoluene (TNT) reduction on a new type of electrodes based on a core-shell tin-carbon Sn(C) structure. The Sn(C) composite was prepared from the precursor tetramethyl-tin Sn(CH 3 ) 4 , and the product contained a core of submicron-sized tin particles uniformly enveloped with carbon shells. Cyclic voltammograms of Sn(C) electrodes in aqueous sodium chloride solutions containing TNT show three well-pronounced reduction waves in the potential range of -0.50 to -0.80 V (vs. an Ag/AgCl/Cl - reference electrode) that correspond to the multistep process of TNT reduction. Electrodes containing Sn(C) particles annealed at 800 deg. C under argon develop higher voltammetric currents of TNT reduction (comparing to the as-prepared tin-carbon material) due to stabilization of the carbon shell. It is suggested that the reduction of TNT on core-shell tin-carbon electrodes is an electrochemically irreversible process. A partial oxidation of the TNT reduction products occurred at around -0.20 V. The electrochemical response of TNT reduction shows that it is not controlled by the diffusion of the active species to/from the electrodes but rather by interfacial charge transfer and possible adsorption phenomena. The tin-carbon electrodes demonstrate significantly stable behavior for TNT reduction in NaCl solutions and provide sufficient reproducibility with no surface fouling through prolonged voltammetric cycling. It is presumed that tin nanoparticles, which constitute the core, are electrochemically inactive towards TNT reduction, but Sn or SnO 2 formed on the electrodes during TNT reduction may participate in this reaction as catalysts or carbon-modifying agents. The nitro-groups of TNT can be reduced irreversibly (via two possible paths) by three six-electron transfers, to 2,4,6-triaminotoluene, as follows from mass-spectrometric studies. The tin-carbon electrodes described herein may serve as amperometric sensors

  17. The relationship between elastic constants and structure of shock waves in a zinc single crystal

    Science.gov (United States)

    Krivosheina, M. N.; Kobenko, S. V.; Tuch, E. V.

    2017-12-01

    The paper provides a 3D finite element simulation of shock-loaded anisotropic single crystals on the example of a Zn plate under impact using a mathematical model, which allows for anisotropy in hydrostatic stress and wave velocities in elastic and plastic ranges. The simulation results agree with experimental data, showing the absence of shock wave splitting into an elastic precursor and a plastic wave in Zn single crystals impacted in the [0001] direction. It is assumed that the absence of an elastic precursor under impact loading of a zinc single crystal along the [0001] direction is determined by the anomalously large ratio of the c/a-axes and close values of the propagation velocities of longitudinal and bulk elastic waves. It is shown that an increase in only one elastic constant along the [0001] direction results in shock wave splitting into an elastic precursor and a shock wave of "plastic" compression.

  18. Mounted Combat System Crew Shock Loading: Head and Neck Injury Potential Evaluation

    National Research Council Canada - National Science Library

    LaFiandra, Michael E; Zywiol, Harry

    2007-01-01

    ...) ride motion simulator (RMS) was used to simulate the effects of gun firing shock on a Hybrid III instrumented anthropometric test device capable of measuring neck force and torque and head acceleration...

  19. Microjetting from grooved surfaces in metallic samples subjected to laser driven shocks

    Science.gov (United States)

    de Rességuier, T.; Lescoute, E.; Sollier, A.; Prudhomme, G.; Mercier, P.

    2014-01-01

    When a shock wave propagating in a solid sample reflects from a free surface, geometrical effects predominantly governed by the roughness and defects of that surface may lead to the ejection of tiny jets that may breakup into high velocity, approximately micrometer-size fragments. This process referred to as microjetting is a major safety issue for engineering applications such as pyrotechnics or armour design. Thus, it has been widely studied both experimentally, under explosive and impact loading, and theoretically. In this paper, microjetting is investigated in the specific loading conditions associated to laser shocks: very short duration of pressure application, very high strain rates, small spatial scales. Material ejection from triangular grooves in the free surface of various metallic samples is studied by combining transverse optical shadowgraphy and time-resolved velocity measurements. The influences of the main parameters (groove angle, shock pressure, nature of the metal) on jet formation and ejection velocity are quantified, and the results are compared to theoretical estimates.

  20. Microjetting from grooved surfaces in metallic samples subjected to laser driven shocks

    International Nuclear Information System (INIS)

    Rességuier, T. de; Lescoute, E.; Sollier, A.; Prudhomme, G.; Mercier, P.

    2014-01-01

    When a shock wave propagating in a solid sample reflects from a free surface, geometrical effects predominantly governed by the roughness and defects of that surface may lead to the ejection of tiny jets that may breakup into high velocity, approximately micrometer-size fragments. This process referred to as microjetting is a major safety issue for engineering applications such as pyrotechnics or armour design. Thus, it has been widely studied both experimentally, under explosive and impact loading, and theoretically. In this paper, microjetting is investigated in the specific loading conditions associated to laser shocks: very short duration of pressure application, very high strain rates, small spatial scales. Material ejection from triangular grooves in the free surface of various metallic samples is studied by combining transverse optical shadowgraphy and time-resolved velocity measurements. The influences of the main parameters (groove angle, shock pressure, nature of the metal) on jet formation and ejection velocity are quantified, and the results are compared to theoretical estimates

  1. Microjetting from grooved surfaces in metallic samples subjected to laser driven shocks

    Energy Technology Data Exchange (ETDEWEB)

    Rességuier, T. de, E-mail: resseguier@ensma.fr [Institut PPRIME, UPR 3346, CNRS, ENSMA, Université de Poitiers, 1 ave. Clément Ader, 86961 Futuroscope Cedex (France); Lescoute, E.; Sollier, A.; Prudhomme, G.; Mercier, P. [CEA, DAM, DIF, 91297 Arpajon (France)

    2014-01-28

    When a shock wave propagating in a solid sample reflects from a free surface, geometrical effects predominantly governed by the roughness and defects of that surface may lead to the ejection of tiny jets that may breakup into high velocity, approximately micrometer-size fragments. This process referred to as microjetting is a major safety issue for engineering applications such as pyrotechnics or armour design. Thus, it has been widely studied both experimentally, under explosive and impact loading, and theoretically. In this paper, microjetting is investigated in the specific loading conditions associated to laser shocks: very short duration of pressure application, very high strain rates, small spatial scales. Material ejection from triangular grooves in the free surface of various metallic samples is studied by combining transverse optical shadowgraphy and time-resolved velocity measurements. The influences of the main parameters (groove angle, shock pressure, nature of the metal) on jet formation and ejection velocity are quantified, and the results are compared to theoretical estimates.

  2. Development and Realization of a Shock Wave Test on Expert Flap Qualification Model

    Science.gov (United States)

    De Fruytier, C.; Dell'Orco, F.; Ullio, R.; Gomiero, F.

    2012-07-01

    This paper presents the methodology and the results of the shock test campaign conducted by TAS-I and TAS ETCA to qualify the EXPERT Flap in regards of shock wave and acoustic load generated by pyrocord detonation at stages 2/3 separation phase of the EXPERT vehicle. The design concept of the open flap (manufactured by MT AEROSPACE) is a fully integral manufactured, four sided control surface, with an additional stiffening rib and flanges to meet the first eigenfrequency and the allowable deformation requirement with a minimum necessary mass. The objectives were to reproduce equivalent loading at test article level in terms of pulse duration, front pressure, front velocity and acoustic emission. The Thales Alenia Space ETCA pyrotechnic shock test device is usually used to produce high level shocks by performing a shock on a test fixture supporting the unit under test. In this case, the facility has been used to produce a shock wave, with different requested physical characteristics, directed to the unit under test. Different configurations have been tried on a dummy of the unit to test, following an empirical process. This unusual work has lead to the definition of a nominal set- up meeting the requested physical parameters. Two blast sensors have been placed to acquire the pressure around the flap. The distance between the two sensors has allowed estimating the front pressure velocity. Then, several locations have been selected to acquire the acceleration responses on the unit when it was submitted to this environment. Additionally, a “standard” shock test has been performed on this model. The qualification of the flap, in regards of shock environment, has been successfully conducted.

  3. Shanghai Futures Exchange Published Draft of Tin and Nickel Futures Contract

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Shanghai Futures Exchange published draft for soliciting opinions for tin and nickel futures contract on its official website on January 19,which implies the marketing time of the long awaited tin and nickel futures is drawing near.According to the draft for soliciting opinions,the transaction unit of tin futures contract is 1tonne/lot,minimum variation unit is 10 yuan/tonne,daily maximum price fluctuation shall

  4. VO2 /TiN Plasmonic Thermochromic Smart Coatings for Room-Temperature Applications.

    Science.gov (United States)

    Hao, Qi; Li, Wan; Xu, Huiyan; Wang, Jiawei; Yin, Yin; Wang, Huaiyu; Ma, Libo; Ma, Fei; Jiang, Xuchuan; Schmidt, Oliver G; Chu, Paul K

    2018-03-01

    Vanadium dioxide/titanium nitride (VO 2 /TiN) smart coatings are prepared by hybridizing thermochromic VO 2 with plasmonic TiN nanoparticles. The VO 2 /TiN coatings can control infrared (IR) radiation dynamically in accordance with the ambient temperature and illumination intensity. It blocks IR light under strong illumination at 28 °C but is IR transparent under weak irradiation conditions or at a low temperature of 20 °C. The VO 2 /TiN coatings exhibit a good integral visible transmittance of up to 51% and excellent IR switching efficiency of 48% at 2000 nm. These unique advantages make VO 2 /TiN promising as smart energy-saving windows. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The Effects of Prior Cold Work on the Shock Response of Copper

    Science.gov (United States)

    Millett, J. C. F.; Higgins, D. L.; Chapman, D. J.; Whiteman, G.; Jones, I. P.; Chiu, Y.-L.

    2018-04-01

    A series of experiments have been performed to probe the effects of dislocation density on the shock response of copper. The shear strength immediately behind the shock front has been measured using embedded manganin stress gauges, whilst the post shock microstructural and mechanical response has been monitored via one-dimensional recovery experiments. Material in the half hard (high dislocation density) condition was shown to have both a higher shear strength and higher rate of change of shear strength with impact stress than its annealed (low dislocation density) counterpart. Microstructural analysis showed a much higher dislocation density in the half hard material compared to the annealed after shock loading, whilst post shock mechanical examination showed a significant degree of hardening in the annealed state with reduced, but still significant amount in the half hard state, thus showing a correlation between temporally resolved stress gauge measurements and post shock microstructural and mechanical properties.

  6. Shock behaviour of 3D carbon-carbon composite

    International Nuclear Information System (INIS)

    Hereil, P.-L.; Allix, O.; Gratton, M.

    1997-01-01

    The compressive response of a 3D carbon-carbon composite under shock wave was studied in a plate-impact configuration. Two directions of impact were achieved until a nominal value of longitudinal stress of 2.5 GPa. The measured wave profiles are consistent with previous results on 3D composites and confirm the behaviour of such materials under impact. It is shown that the initial loading is decomposed in two waves. The first one is transmitted by the longitudinal fibres, the second one corresponds to the propagation of a shock wave in the 'matrix'. Macroscopic characteristics of this material are provided. (orig.)

  7. Tinned fish with radioprotective ingredients

    International Nuclear Information System (INIS)

    Chaneva, M.; Minkova, M.; Zajko, G.

    1992-01-01

    A survey of food ingredients with pronounced radioprotective properties is made. The protective effect of fish proteins and some vegetable oils is mentioned. As suitable additives to tinned fish during the manufacturing process the β carotene, anthocyans and apple pectin are pointed out. β-carotene possesses the ability to absorb radiations. It can be added either as a pure crystalline substance or dissolved in the vegetable oil. Anthocyans have an antimutagen effect due to their ability to inhibit free radical reactions. Some vegetable polyphenols can be added with wine. The Bulgarian anthocyan concentrate Enobagrin (made by extraction of marc and wine) is also proposed. A combination of Enobagrin, β-tocopherol and pyracetam decreases the postradiation hypoplasia. Special attention is paid to the importance of the pectin in intoxication with heavy radioactive metals. It is thought that the pectin forms unsoluble complex compounds with Fe, Zn, Cd, Co, Pb, Hg, Mn, Cr. The binding energy depends on the available carboxylic groups. Some experiments showing the interaction of the pectin with 90 Sr are mentioned. In the tinned fish the pectin can be introduced with tomato paste. Vegetables rich in pectin and carotene - carrots and tomato concentrate - can be added as well. Proposed enriched tinned fish can be used as a preventive radioprotective food under conditions of increased radiation risk. 19 refs

  8. Shock and vibration tests of uranium mononitride fuel pellets for a space power nuclear reactor

    Science.gov (United States)

    Adams, D. W.

    1972-01-01

    Shock and vibration tests were conducted on cylindrically shaped, depleted, uranium mononitride (UN) fuel pellets. The structural capabilities of the pellets were determined under exposure to shock and vibration loading which a nuclear reactor may encounter during launching into space. Various combinations of diametral and axial clearances between the pellets and their enclosing structures were tested. The results of these tests indicate that for present fabrication of UN pellets, a diametral clearance of 0.254 millimeter and an axial clearance of 0.025 millimeter are tolerable when subjected to launch-induced loads.

  9. Separation of substandard tin ores by x-ray fluorescence method

    International Nuclear Information System (INIS)

    Kotler, N.I.; Konovalov, V.M.; Kamenskij, Yu.V.; Neverov, A.D.; Ogorodnikov, Yu.V.

    1987-01-01

    Analysis of pure tin ores on X-ray fluorescence separation (XFS) is carried out. The volumes of lump sampling are substantiated; several variants of technical and economical efficiency of XFS application have been calculated. It is shown that at XFS of -400+25 mm classes conditional as to tin content intermediate product with high efficiency factor may be prepared. Separation of -25+10 mm class is unsuitable, as it doesn't allow to increase tin content to conditional, and the process efficiency is low

  10. Tin - an unlikely ally for silicon field effect transistors?

    KAUST Repository

    Hussain, Aftab M.

    2014-01-13

    We explore the effectiveness of tin (Sn), by alloying it with silicon, to use SiSn as a channel material to extend the performance of silicon based complementary metal oxide semiconductors. Our density functional theory based simulation shows that incorporation of tin reduces the band gap of Si(Sn). We fabricated our device with SiSn channel material using a low cost and scalable thermal diffusion process of tin into silicon. Our high-κ/metal gate based multi-gate-field-effect-transistors using SiSn as channel material show performance enhancement, which is in accordance with the theoretical analysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Preparation and optical properties of Eu3+-doped tin oxide nanoparticles

    International Nuclear Information System (INIS)

    Wang, Guofeng; Yang, Yiping; Mu, Qiuying; Wang, Yude

    2010-01-01

    Eu 3+ -doped SnO 2 nanoparticles with high surface area were generated within the template of the cationic surfactant (cetyltrimethylammonium bromide, CTAB) micelle assembly by surfactant-mediated method from the hydrous tin chloride (SnCl 4 .5H 2 O) and europium chloride (EuCl 3 .6H 2 O). The as-synthesized product was amorphous and transformed into crystalline calcined at 500 o C for 2 h. DSC-TGA, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were used to examine the morphology and microstructure of the final products. The results showed that the Eu 3+ -doped SnO 2 nanoparticles with diameter of 3-7 nm were obtained. The influences of the molar ratios of Eu 3+ and CTAB on the room temperature photoluminescence (RTPL) properties of Eu 3+ -doped SnO 2 nanoparticles were investigated. The results showed that the contents of Eu 3+ and CTAB had a great influence on the crystallite sizes and RTPL properties of Eu 3+ :SnO 2 nanoparticles. The maximum of the RTPL intensity can be observed at the molar ratio 5.0% Eu 3+ and 10.0% CTAB.

  12. Numerical simulation of shock initiation of Ni/Al multilayered composites

    Energy Technology Data Exchange (ETDEWEB)

    Sraj, Ihab; Knio, Omar M., E-mail: omar.knio@duke.edu [Department of Mechanical Engineering and Materials Science, Duke University, 144 Hudson Hall, Durham, North Carolina 27708 (United States); Specht, Paul E.; Thadhani, Naresh N. [School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive, Atlanta, Georgia 30332 (United States); Weihs, Timothy P. [Department of Materials Science and Engineering, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218 (United States)

    2014-01-14

    The initiation of chemical reaction in cold-rolled Ni/Al multilayered composites by shock compression is investigated numerically. A simplified approach is adopted that exploits the disparity between the reaction and shock loading timescales. The impact of shock compression is modeled using CTH simulations that yield pressure, strain, and temperature distributions within the composites due to the shock propagation. The resulting temperature distribution is then used as initial condition to simulate the evolution of the subsequent shock-induced mixing and chemical reaction. To this end, a reduced reaction model is used that expresses the local atomic mixing and heat release rates in terms of an evolution equation for a dimensionless time scale reflecting the age of the mixed layer. The computations are used to assess the effect of bilayer thickness on the reaction, as well as the impact of shock velocity and orientation with respect to the layering. Computed results indicate that initiation and evolution of the reaction are substantially affected by both the shock velocity and the bilayer thickness. In particular, at low impact velocity, Ni/Al multilayered composites with thick bilayers react completely in 100 ms while at high impact velocity and thin bilayers, reaction time was less than 100 μs. Quantitative trends for the dependence of the reaction time on the shock velocity are also determined, for different bilayer thickness and shock orientation.

  13. Tin Whisker Formation — A Stress Relieve Phenomenon

    Science.gov (United States)

    Dittes, M.; Oberndorff, P.; Crema, P.; Su, P.

    2006-02-01

    With the move towards lead-free electronics also the solderable finish of electronic components' terminations are converted. While the typical finish was containing 5 % to 20 % lead (Pb) and thus was almost whisker free, lead (Pb)-free finishes such as pure tin or high tin alloys are rather prone to grow whisker. These whiskers are spontaneous protrusions that grow to a significant length of up to millimeters with a typical diameter in the range of few microns and are suspect to cause shorts in electronic assemblies. The latest details of the mechanisms are not yet understood. However it appears to be well established that the driving force for tin whisker growth is a compressive stress in the tin layer and that this stress is released by whisker formation. Besides the mechanism for whisker growth therefore the mechanism of the stress induction is of interest. The origin of that stress may have multiple sources. Among others the most important one is the volume increase within the tin layer due the formation of intermetallics at the interface to the base material. This applies to all copper based material. For base materials with a coefficient of thermal expansion (cte) significantly different from the tin finish another mechanism plays the dominant role. This is the induction of stress during thermal cycling due to the different expansion of the materials with every temperature change. Another mechanism for stress induction may be the oxidation of the finish, which also leads to a local volume increase. Based on the knowledge of stress induction various mitigation strategies can be deducted. Most common is the introduction of a diffusion barrier (e.g. Ni) in order to prevent the growth of the Cu-Sn intermetallics, the controlled growth of Cu-Sn intermetallics in order to prevent their irregularity or the introduction of a mechanical buffer material targeting at the minimisation of the cte mismatch between base and finish material. With respect to the stress

  14. Effect of triangular texture on the tribological performance of die steel with TiN coatings under lubricated sliding condition

    Science.gov (United States)

    Chen, Ping; Xiang, Xin; Shao, Tianmin; La, Yingqian; Li, Junling

    2016-12-01

    The friction and wear of stamping die surface can affect the service life of stamping die and the quality of stamping products. Surface texturing and surface coating have been widely used to improve the tribological performance of mechanical components. This study experimentally investigated the effect of triangular surface texture on the friction and wear properties of the die steel substrate with TiN coatings under oil lubrication. TiN coatings were deposited on a die steel (50Cr) substrate through a multi-arc ion deposition system, and then triangular surface texturing was fabricated by a laser surface texturing. The friction and wear test was conducted by a UMT-3 pin-on-disk tribometer under different sliding speeds and different applied loads, respectively. The adhesion test was performed to evaluate the effectiveness of triangular texturing on the interfacial bonding strength between the TiN coating and the die steel substrate. Results show that the combination method of surface texturing process and surface coating process has excellent tribological properties (the lowest frictional coefficient and wear volume), compared with the single texturing process or the single coating process. The tribological performance is improved resulting from the high hardness and low elastic modulus of TiN coatings, and the generation of hydrodynamic pressure, function of micro-trap for wear debris and micro-reservoirs for lubricating oil of the triangular surface texture. In addition, the coating bonding strength of the texturing sample is 3.63 MPa, higher than that of the single coating sample (3.48 MPa), but the mechanisms remain to be further researched.

  15. Electrochemical migration of tin in electronics and microstructure of the dendrites

    DEFF Research Database (Denmark)

    Minzari, Daniel; Grumsen, Flemming Bjerg; Jellesen, Morten Stendahl

    2011-01-01

    The macro-, micro-, and nano-scale morphology and structure of tin dendrites, formed by electrochemical migration on a surface mount ceramic chip resistor having electrodes consisting of tin with small amounts of Pb (∼2wt.%) was investigated by scanning electron microscopy and transmission electr...... by the dehydration of the hydrated oxide originally formed in solution ex-situ in ambient air.......The macro-, micro-, and nano-scale morphology and structure of tin dendrites, formed by electrochemical migration on a surface mount ceramic chip resistor having electrodes consisting of tin with small amounts of Pb (∼2wt.%) was investigated by scanning electron microscopy and transmission electron...... microscopy including Energy dispersive X-ray spectroscopy and electron diffraction. The tin dendrites were formed under 5 or 12V potential bias in 10ppm by weight NaCl electrolyte as a micro-droplet on the resistor during electrochemical migration experiments. The dendrites formed were found to have...

  16. Trace hydrogen extraction from liquid lithium tin alloy

    International Nuclear Information System (INIS)

    Xie Bo; Hu Rui; Xie Shuxian; Weng Kuiping

    2010-01-01

    In order to finish the design of tritium extraction system (TES) of fusion fission hybrid reactor (FFHR) tritium blanket, involving the dynamic mathematical model of liquid metal in contact with a gaseous atmosphere, approximate mathematical equation of tritium in lithium tin alloy was deduced. Moreover, carrying process used for trace hydrogen extraction from liquid lithium tin alloy was investigated with hydrogen being used to simulate tritium in the study. The study results indicate that carrying process is effective way for hydrogen extraction from liquid lithium tin alloy, and the best flow velocity of carrier gas is about 4 L/min under 1 kg alloy temperatures and carrying numbers are the main influencing factors of hydrogen number. Hydrogen extraction efficiency can reach 85% while the alloy sample is treated 6 times at 823 K. (authors)

  17. Shock absorber in combination with a nuclear reactor core structure

    International Nuclear Information System (INIS)

    Housman, J.J.

    1976-01-01

    This invention relates to the provision of shock absorbers for use in blind control rod passages of a nuclear reactor core structure which are not subject to degradation. The shock absorber elements are made of a porous brittle carbonaceous material, a porous brittle ceramic material, or a porous brittle refractory oxide and have a void volume of between 30% and 70% of the total volume of the element for energy absorption by fracturing due to impact loading by a control rod. (UK)

  18. Selective Recovery of Mushistonite from Gravity Tailings of Copper–Tin Minerals in Tajikistan

    Directory of Open Access Journals (Sweden)

    Lei Sun

    2017-12-01

    Full Text Available Tajikistan has abundant copper–tin resources. In this study, mineralogical analysis of copper–tin ores from the Mushiston deposit of Tajikistan indicates that tin mainly occurred in mushistonite, cassiterite, and stannite, while copper mainly occurred in mushistonite, malachite, azurite, and stannite. The total grades of tin (Sn and copper (Cu were 0.65% and 0.66%, respectively, and the dissemination size of copper–tin minerals ranged from 4 μm to over 200 μm. Coarse particles of copper–tin minerals were partially recovered by shaking table concentrators with a low recovery rate. Based on the mineralogical analysis, flotation recovery was used for the first time on the fine particles of copper–tin minerals, including mushistonite, from shaking table tailings. Single factor flotation experiments, open circuit flotation tests, and closed circuit flotation tests were performed to determine the optimized flotation conditions. Results indicated that benzohydroxamic acid (C6H5CONHOH and lead nitrate could effectively recover the mushistonite, cooperating with other depressants. The final concentrate contained 13.28% Sn, with a recovery rate of 61.56%, and 18.51% Cu, with a recovery rate of 86.52%. This method proved effective for the exploitation and use of this type of copper–tin resource in Tajikistan.

  19. Effect of applied voltage on the structural properties of SnO2 nanostuctures grown on indium-tin-oxide coated glass substrates.

    Science.gov (United States)

    Lee, Dea Uk; Yun, Dong Yeol; No, Young Soo; Hwang, Jun Ho; Lee, Chang Hun; Kim, Tae Whan

    2013-11-01

    SnO2 nanostuctures were formed on indium-tin-oxide (ITO)-coated glass substrates by using an electrochemical deposition (ECD) method. X-ray photoelectron spectroscopy (XPS) spectra showed the existence of elemental Sn and O in the samples, indicative of the formation of SnO2 materials. An XPS spectrum showing the O 1s peak at a binding energy of 531.5 eV indicated that the oxygen atoms were bonded to the SnO2. Field-emission scanning electron microscopy (FE-SEM) images showed that the samples formed by using the ECD method had SnO2 nanostructures with a size between 280 and 350 nm. FE-SEM images showed that the size of the SnO2 nanostructures formed at 65 degrees C for 30 min increased with decreasing applied voltage. X-ray diffraction (XRD) patterns showed that the SnO2 nanostrucures had tetragonal structures with cell parameters of a = 4.738 A and c = 3.187 A. XRD results showed that the peak intensity of the (110) plane increased with decreasing applied voltage, indicative of a preferencial orientation of the (110) plane.

  20. Determination of total tin in canned food using inductively coupled plasma atomic emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Perring, Loic; Basic-Dvorzak, Marija [Department of Quality and Safety Assurance, Nestle Research Centre, P.O. Box 44, Vers chez-les-Blanc, 1000, Lausanne (Switzerland)

    2002-09-01

    Tin is considered to be a priority contaminant by the Codex Alimentarius Commission. Tin can enter foods either from natural sources, environmental pollution, packaging material or pesticides. Higher concentrations are found in processed food and canned foods. Dissolution of the tinplate depends on the of food matrix, acidity, presence of oxidising reagents (anthocyanin, nitrate, iron and copper) presence of air (oxygen) in the headspace, time and storage temperature. To reduce corrosion and dissolution of tin, nowadays cans are usually lacquered, which gives a marked reduction of tin migration into the food product. Due to the lack of modern validated published methods for food products, an ICP-AES (Inductively coupled plasma-atomic emission spectroscopy) method has been developed and evaluated. This technique is available in many laboratories in the food industry and is more sensitive than atomic absorption. Conditions of sample preparation and spectroscopic parameters for tin measurement by axial ICP-AES were investigated for their ruggedness. Two methods of preparation involving high-pressure ashing or microwave digestion in volumetric flasks were evaluated. They gave complete recovery of tin with similar accuracy and precision. Recoveries of tin from spiked products with two levels of tin were in the range 99{+-}5%. Robust relative repeatabilities and intermediate reproducibilities were <5% for different food matrices containing >30 mg/kg of tin. Internal standard correction (indium or strontium) did not improve the method performance. Three emission lines for tin were tested (189.927, 283.998 and 235.485 nm) but only 189.927 nm was found to be robust enough with respect to interferences, especially at low tin concentrations. The LOQ (limit of quantification) was around 0.8 mg/kg at 189.927 nm. A survey of tin content in a range of canned foods is given. (orig.)

  1. Optical and Electrical Properties of Tin-Doped Cadmium Oxide Films Prepared by Electron Beam Technique

    Science.gov (United States)

    Ali, H. M.; Mohamed, H. A.; Wakkad, M. M.; Hasaneen, M. F.

    2009-04-01

    Tin-doped cadmium oxide films were deposited by electron beam evaporation technique. The structural, optical and electrical properties of the films were characterized. The X-ray diffraction (XRD) study reveals that the films are polycrystalline in nature. As composition and structure change due to the dopant ratio and annealing temperature, the carrier concentration was varied around 1020 cm-3, and the mobility increased from less than 10 to 45 cm2 V-1 s-1. A transmittance value of ˜83% and a resistivity value of 4.4 ×10-4 Ω cm were achieved for (CdO)0.88(SnO2)0.12 film annealed at 350 °C for 15 min., whereas the maximum value of transmittance ˜93% and a resistivity value of 2.4 ×10-3 Ω cm were obtained at 350 °C for 30 min. The films exhibited direct band-to-band transitions, which corresponded to optical band gaps of 3.1-3.3 eV.

  2. Contribution of tin in electrochemical properties of zinc antimonate nanostructures: An electrode material for supercapacitors

    Science.gov (United States)

    Balasubramaniam, M.; Balakumar, S.

    2018-04-01

    Tin (Sn) doped ZnSb2O6 nanostructures was synthesized by chemical precipitation method and was used as an electrode material for supercapacitors to explore its electrochemical stability and potentiality as energy storage materials. Their characteristic structural, morphological and compositional features were investigated through XRD, FESEM and XPS analysis. Results showed that the nanostructures have well ordered crystalline features with spherical particle morphology. As the size and morphology are the vital parameters in exhibiting better electrochemical properties, the prepared nanostructures exhibited a significant specific capacitance of 222 F/g at a current density of 0.5 A/g respectively. While charging and discharging for 1000 cycles, the capacitance retention was enhanced to 105.0% which depicts the stability and activeness of electrochemical sites present in the Sn doped ZnSb2O6 nanostructures even after cycling. Hence, the inclusion of Sn into ZnSb2O6 has contributed in improving the electrochemical properties thereby it represents itself as a potential electrode material for supercapacitors.

  3. Effect of oxidizer on grain size and low temperature DC electrical conductivity of tin oxide nanomaterial synthesized by gel combustion method

    International Nuclear Information System (INIS)

    Rajeeva, M. P.; Jayanna, H. S.; Ashok, R. L.; Naveen, C. S.; Bothla, V. Prasad

    2014-01-01

    Nanocrystalline Tin oxide material with different grain size was synthesized using gel combustion method by varying the fuel (C 6 H 8 O 7 ) to oxidizer (HNO 3 ) molar ratio by keeping the amount of fuel as constant. The prepared samples were characterized by using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive Analysis X-ray Spectroscopy (EDAX). The effect of fuel to oxidizer molar ratio in the gel combustion method was investigated by inspecting the grain size of nano SnO 2 powder. The grain size was found to be reduced with the amount of oxidizer increases from 0 to 6 moles in the step of 2. The X-ray diffraction patterns of the calcined product showed the formation of high purity tetragonal tin (IV) oxide with the grain size in the range of 12 to 31 nm which was calculated by Scherer's formula. Molar ratio and temperature dependence of DC electrical conductivity of SnO 2 nanomaterial was studied using Keithley source meter. DC electrical conductivity of SnO 2 nanomaterial increases with the temperature from 80K to 300K. From the study it was observed that the DC electrical conductivity of SnO 2 nanomaterial decreases with the grain size at constant temperature

  4. Influence of phase separation on the anaerobic digestion of glucose-II stability, and kinetic responses to shock loadings

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, A; Breure, A M; Van Andel, J G; Van Deursen, A

    1982-01-01

    A mineral medium, containing 1% (w/v) glucose as the main carbon source, was subjected to one-phase and to two-phase anaerobic digestion processes under comparable conditions. The one-phase system consisted of an anaerobic up-flow reactor containing both acidogenic as well as methanogenic populations. The two-phase system consisted of an acid reactor and a methane reactor connected in series allowing sequential acidogenesis and methanogenesis of the glucose. After maximum turnover rates of glucose had been attained in both systems, by gradually increasing feed supply rate, both systems were switched to the batch mode and subjected to shock loadings with glucose or fatty acids. Maximum specific turnover rates of fatty acids in the one-phase process averaged 0.39 g chemical oxygen demand (COD)-g biomass/sup -1/ d/sup -1/ and 2.23 g g/sup -1/ d/sup -1/ for the methane reactor of the two-phase system. Charging the one-phase system with doses of glucose resulted mainly in an accumulation of propionate which was degraded relatively slowly. It was concluded that interspecies hydrogen transfer may become rate limiting at high loading rates, stimulating formation of propionate. Therefore a two-phase system, as compared with a one-phase digestion process for easily hydrolyzable carbohyrates, was characterized as being essentially the more stable.

  5. Inductively coupled plasma atomic emission spectrometric determination of tin in canned food.

    Science.gov (United States)

    Sumitani, H; Suekane, S; Nakatani, A; Tatsuka, K

    1993-01-01

    Various canned foods were digested sequentially with HNO3 and HCl, diluted to 100 mL, and filtered, and then tin was determined by inductively coupled plasma atomic emission spectrometry (ICP/AES). Samples of canned Satsuma mandarin, peach, apricot, pineapple, apple juice, mushroom, asparagus, evaporated milk, short-necked clam, spinach, whole tomato, meat, and salmon were evaluated. Sample preparations did not require time-consuming dilutions, because ICP/AES has wide dynamic range. The standard addition method was used to determine tin concentration. Accuracy of the method was tested by analyzing analytical standards containing tin at 2 levels (50 and 250 micrograms/g). The amounts of tin found for the 50 and 250 micrograms/g levels were 50.5 and 256 micrograms/g, respectively, and the repeatability coefficients of variation were 4.0 and 3.8%, respectively. Recovery of tin from 13 canned foods spiked at 2 levels (50 and 250 micrograms/g) ranged from 93.9 to 109.4%, with a mean of 99.2%. The quantitation limit for tin standard solution was about 0.5 microgram/g.

  6. Shock Transmission Analyses of a Simplified Frigate Compartment Using LS-DYNA

    National Research Council Canada - National Science Library

    Trouwborst, W

    1999-01-01

    This report gives results as obtained with finite element analyses using the explicit finite element program LS-DYNA for a longitudinal slice of a frigate's compartment loaded with a shock pulse based...

  7. Preparation and characterization of tin sulphide thin films by a spray pyrolysis technique

    International Nuclear Information System (INIS)

    Ben Haj Salah, H.; Bouzouita, H.; Rezig, B.

    2005-01-01

    We have attempted the preparation and characterization of Sn 2 S 3 thin films by using the spray pyrolysis technique. We started with acidic aqueous solutions including tin (II) chloride and thiourea, which were atomized with compressed air as carrier gas. The Sn 2 S 3 thin films were obtained on glass substrates. Thin layers of Sn-S have been grown at various temperatures in the range of 275-325 deg. C and various [S/Sn] ratios. The structural properties have been determined by using X-ray diffraction (XRD). The changes observed in the structural phases during the film formation in dependence of growth temperatures are reported and discussed. The optical constants of the deposited films were obtained using the experimentally recorded transmission and reflectance spectral data as functions of the wavelength, in the range of 300-1800 nm. An analysis of the deduced spectral absorption of the deposited films revealed an optical indirect band gap energy of 1.9-2.2 eV for Sn 2 S 3 layers

  8. Observation of the shock wave propagation induced by a high-power laser irradiation into an epoxy material

    International Nuclear Information System (INIS)

    Ecault, Romain; Boustie, Michel; Touchard, Fabienne; Berthe, Laurent; Lescoute, Emilien; Sollier, Arnaud; Mercier, Patrick; Benier, Jacky

    2013-01-01

    The propagation of laser-induced shock waves in a transparent epoxy sample is investigated by optical shadowgraphy. The shock waves are generated by a focused laser (3 ns pulse duration—1.2 to 3.4 TW cm −2 ) producing pressure from 44 to 98.9 GPa. It is observed that the shock wave and the release wave created by the shock reverberation at the rear face are both followed by a dark zone in the pictures. This corresponds to the creation of a tensile zone resulting from the crossing on the loading axis of the release waves coming from the edge of the impact area (2D effects). After the laser shock experiment, the residual stresses in the targets are identified and quantified through a photoelasticimetry analysis of the recovered samples. This work results in a new set of original data which can be directly used to validate numerical models implemented to reproduce the behaviour of epoxy under extreme strain rate loading. The residual stresses observed prove that the high-pressure shocks can modify the pure epoxy properties, which could have an influence on the use made of these materials. (paper)

  9. Quadtree of TIN: a new algorithm of dynamic LOD

    Science.gov (United States)

    Zhang, Junfeng; Fei, Lifan; Chen, Zhen

    2009-10-01

    Currently, Real-time visualization of large-scale digital elevation model mainly employs the regular structure of GRID based on quadtree and triangle simplification methods based on irregular triangulated network (TIN). TIN is a refined means to express the terrain surface in the computer science, compared with GRID. However, the data structure of TIN model is complex, and is difficult to realize view-dependence representation of level of detail (LOD) quickly. GRID is a simple method to realize the LOD of terrain, but contains more triangle count. A new algorithm, which takes full advantage of the two methods' merit, is presented in this paper. This algorithm combines TIN with quadtree structure to realize the view-dependence LOD controlling over the irregular sampling point sets, and holds the details through the distance of viewpoint and the geometric error of terrain. Experiments indicate that this approach can generate an efficient quadtree triangulation hierarchy over any irregular sampling point sets and achieve dynamic and visual multi-resolution performance of large-scale terrain at real-time.

  10. Experimental Study on Reaction Characteristics of PTFE/Ti/W Energetic Materials under Explosive Loading

    Directory of Open Access Journals (Sweden)

    Yan Li

    2016-11-01

    Full Text Available Metal/fluoropolymer composites represent a new category of energetic structural materials that release energy through exothermic chemical reactions initiated under shock loading conditions. This paper describes an experiment designed to study the reaction characteristics of energetic materials with low porosity under explosive loading. Three PTFE (polytetrafluoroethylene/Ti/W mixtures with different W contents are processed through pressing and sintering. An inert PTFE/W mixture without reactive Ti particles is also prepared to serve as a reference. Shock-induced chemical reactions are recorded by high-speed video through a narrow observation window. Related shock parameters are calculated based on experimental data, and differences in energy release are discussed. The results show that the reaction propagation of PTFE/Ti/W energetic materials with low porosity under explosive loading is not self-sustained. As propagation distance increases, the energy release gradually decreases. In addition, reaction failure distance in PTFE/Ti/W composites is inversely proportional to the W content. Porosity increased the failure distance due to higher shock temperature.

  11. Properties of Polydisperse Tin-doped Dysprosium and Indium Oxides

    Directory of Open Access Journals (Sweden)

    Malinovskaya Tatyana

    2017-01-01

    Full Text Available The results of investigations of the complex permittivity, diffuse-reflectance, and characteristics of crystal lattices of tin-doped indium and dysprosium oxides are presented. Using the methods of spectroscopy and X-ray diffraction analysis, it is shown that doping of indium oxide with tin results in a significant increase of the components of the indium oxide complex permittivity and an appearance of the plasma resonance in its diffuse-reflectance spectra. This indicates the appearance of charge carriers with the concentration of more than 1021 cm−3 in the materials. On the other hand, doping of the dysprosium oxide with the same amount of tin has no effect on its optical and electromagnetic properties.

  12. Thermal-shock experiments with flawed clad cylinders

    International Nuclear Information System (INIS)

    Cheverton, R.D.; Bryson, J.W.; Alexander, D.J.

    1989-01-01

    The life expectancy of LWR pressure vessels is influenced by a reduction in fracture toughness that is the result of radiation damage. As the fracture toughness decreases, the probability of propagation of preexisting flaws (sharp, crack-like defects) in the wall of the vessel increases. The probability of propagation is also influenced by the type of loading condition and the type of flaws that might exist. A loading condition of particular concern is referred to as pressurized thermal shock (PTS), and a flaw of particular concern for PTS loading conditions is a shallow surface flaw. A sudden cooling (thermal shock) of the inner surface of the vessel results in relatively high tensile stresses and relatively low fracture toughness at the inner surface. In addition, the attenuation of the fast-neutron fluence also results in relatively low fracture toughness at the inner surface. Under some circumstances, this combination of high stress and low toughness at the inner surface makes it possible for very shallow surface flaws to propagate. The PTS issue has been under investigation for quite some time, but thus far possible beneficial effects, other than thermal resistance, of the cladding on the inner surface of the vessel have not been included in the analysis of flaw behavior. This document discusses this effect of cladding on surface flaws and crack propagation

  13. Performance of multifilamentary Nb3Sn under mechanical load

    International Nuclear Information System (INIS)

    Easton, D.S.; Schwall, R.E.

    1976-11-01

    The critical current density of commercial multifilamentary Nb 3 Sn conductor has been measured during the application of uniaxial tension at 4.2 0 K and after bending at room temperature. Significant reductions in the critical current density J/sub c/ occurred under uniaxial loading. Results are presented for a monolithic conductor manufactured by the bronze diffusion technique and for cable conductors formed by the tin-dip technique

  14. Analysis of the computational methods on the equipment shock response based on ANSYS environments

    International Nuclear Information System (INIS)

    Wang Yu; Li Zhaojun

    2005-01-01

    With the developments and completions of equipment shock vibration theory, math calculation method simulation technique and other aspects, equipment shock calculation methods are gradually developing form static development to dynamic and from linearity to non-linearity. Now, the equipment shock calculation methods applied worldwide in engineering practices mostly include equivalent static force method, Dynamic Design Analysis Method (abbreviated to DDAM) and real-time simulation method. The DDAM is a method based on the modal analysis theory, which inputs the shock design spectrum as shock load and gets hold of the shock response of the integrated system by applying separate cross-modal integrating method within the frequency domain. The real-time simulation method is to carry through the computational analysis of the equipment shock response within the time domain, use the time-history curves obtained from real-time measurement or spectrum transformation as the equipment shock load and find an iterative solution of a differential equation of the system movement by using the computational procedure within the time domain. Conclusions: Using the separate DDAM and Real-time Simulation Method, this paper carried through the shock analysis of a three-dimensional frame floating raft in ANSYS environments, analyzed the result, and drew the following conclusion: Because DDAM does not calculate damping, non-linear effect and phase difference between mode responses, the result is much bigger than that of real-time simulation method. The coupling response is much complex when the mode result of 3-dimension structure is being calculated, and the coupling response of non-shock direction is also much bigger than that of real-time simulation method when DDAM is applied. Both DDAM and real-time simulation method has its good points and scope of application. The designers should select the design method that is economic and in point according to the features and anti-shock

  15. INTERIM RESULTS FROM A STUDY OF THE IMPACTS OF TIN(II) BASED MERCURY TREATMENT IN A SMALL STREAM ECOSYSTEM: TIMS BRANCH, SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Bryan, L.; Mathews, T.

    2012-03-30

    Mercury (Hg) has been identified as a 'persistent, bioaccumulative and toxic' pollutant with widespread impacts throughout North America and the world (EPA. 1997a, 1997b, 1998a, 1998b, 2000). Although most of the mercury in the environment is inorganic Hg, a small proportion of total Hg is transformed through the actions of aquatic microbes into methylmercury (MeHg). In contrast to virtually all other metals, MeHg biomagnifies or becomes increasingly concentrated as it is transferred through aquatic food chains so that the consumption of mercury contaminated fish is the primary route of this toxin to humans. For this reason, the ambient water quality criterion (AWQC) for mercury is based on a fish tissue endpoint rather than an aqueous Hg concentration, as the tissue concentration (e.g., < 0.3 {mu}g/g fillet) is considered to be a more consistent indicator of exposure and risk (EPA, 2001). Effective mercury remediation at point-source contaminated sites requires an understanding of the nature and magnitude of mercury inputs, and also knowledge of how these inputs must be controlled in order to achieve the desired reduction of mercury contamination in biota necessary for compliance with AWQC targets. One of the challenges to remediation is that mercury body burdens in fish are more closely linked to aqueous MeHg than to inorganic Hg concentrations (Sveinsdottir and Mason 2005), but MeHg production is not easily predicted or controlled. At point-source contaminated sites, mercury methylation is not only affected by the absolute mercury load, but also by the form of mercury loaded. In addition, once MeHg is formed, the hydrology, trophic structure, and water chemistry of a given system affect how it is transformed and transferred through the food chain to fish. Decreasing inorganic Hg concentrations and loading may often therefore be a more achievable remediation goal, but has led to mixed results in terms of responses in fish bioaccumulation. A number of

  16. Shock compression and flash-heating of molecular adsorbates on the picosecond time scale

    Science.gov (United States)

    Berg, Christopher Michael

    An ultrafast nonlinear coherent laser spectroscopy termed broadband multiplex vibrational sum-frequency generation (SFG) with nonresonant suppression was employed to monitor vibrational transitions of molecular adsorbates on metallic substrates during laser-driven shock compression and flash-heating. Adsorbates were in the form of well-ordered self-assembled monolayers (SAMs) and included molecular explosive simulants, such as nitroaromatics, and long chain-length alkanethiols. Based on reflectance measurements of the metallic substrates, femtosecond flash-heating pulses were capable of producing large-amplitude temperature jumps with DeltaT = 500 K. Laser-driven shock compression of SAMs produced pressures up to 2 GPa, where 1 GPa ≈ 1 x 104 atm. Shock pressures were estimated via comparison with frequency shifts observed in the monolayer vibrational transitions during hydrostatic pressure measurements in a SiC anvil cell. Molecular dynamics during flash-heating and shock loading were probed with vibrational SFG spectroscopy with picosecond temporal resolution and sub-nanometer spatial resolution. Flash-heating studies of 4-nitrobenzenethiolate (NBT) on Au provided insight into effects from hot-electron excitation of the molecular adsorbates at early pump-probe delay times. At longer delay times, effects from the excitation of SAM lattice modes and lower-energy NBT vibrations were shown. In addition, flash-heating studies of alkanethiolates demonstrated chain disordering behaviors as well as interface thermal conductances across the Au-SAM junction, which was of specific interest within the context of molecular electronics. Shock compression studies of molecular explosive simulants, such as 4-nitrobenzoate (NBA), demonstrated the proficiency of this technique to observe shock-induced molecular dynamics, in this case orientational dynamics, on the picosecond time scale. Results validated the utilization of these refined shock loading techniques to probe the shock

  17. Time-resolved shock compression of porous rutile: Wave dispersion in porous solids

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M.U.; Graham, R.A.; Holman, G.T.

    1993-08-01

    Rutile (TiO{sub 2}) samples at 60% of solid density have been shock-loaded from 0.21 to 6.1 GPa with sample thickness of 4 mm and studied with the PVDF piezoelectric polymer stress-rate gauge. The technique uses a copper capsule to contain the sample which has PVDF gauge packages in direct contact with front and rear surfaces. A precise measure is made of the compressive stress wave velocity through the sample, as well as the input and propagated shock stress. Initial density is known from sample preparation, and the amount of shock-compression is calculated from the measurement of shock velocity and input stress. Shock states and re-shock states are measured. Observed data are consistent with previously published high pressure data. It is observed that rutile has a ``crush strength`` near 6 GPa. Propagated stress-pulse rise times vary from 234 to 916 nsec. Propagated stress-pulse rise times of shock-compressed HMX, 2Al + Fe{sub 2}O{sub 3}, 3Ni + Al, and 5Ti + 3Si are presented.

  18. Laser-generated shock wave attenuation aimed at microscale pyrotechnic device design

    Directory of Open Access Journals (Sweden)

    Hyeonju Yu

    2016-05-01

    Full Text Available To meet the rising demand for miniaturizing the pyrotechnic device that consists of donor/acceptor pair separated by a bulkhead or a thin gap, the shock initiation sensitivity in the microscale gap test configuration is investigated. For understanding the shock attenuation within a gap sample (304 stainless steel thickness of 10∼800 μm, the laser-generated shock wave in water confinement is adopted. The shock properties are obtained from the free surface velocity by making use of a velocity interferometer system for any reflector (VISAR. Analytical models for plasma generation in a confined geometry and for evolution and decay of shock waves during the propagation are considered. The shape and amplitude of the laser-driven initial pressure load and its attenuation pattern in the gap are effectively controlled for targeting the microscale propagation distance and subsequent triggering pressure for the acceptor charge. The reported results are important in the precise controlling of the shock strength during the laser initiation of microscale pyrotechnic devices.

  19. Dynamic analytical and experimental research of shock absorber to safeguard the nuclear fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Dundulis, Gintautas, E-mail: gintas@mail.lei.lt [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, Breslaujos str. 3, LT-44403 Kaunas (Lithuania); Grybenas, Albertas [Laboratory of Materials Research and Testing, Lithuanian Energy Institute, Breslaujos str. 3, LT-44403 Kaunas (Lithuania); Karalevicius, Renatas [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, Breslaujos str. 3, LT-44403 Kaunas (Lithuania); Makarevicius, Vidas [Laboratory of Materials Research and Testing, Lithuanian Energy Institute, Breslaujos str. 3, LT-44403 Kaunas (Lithuania); Rimkevicius, Sigitas; Uspuras, Eugenijus [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, Breslaujos str. 3, LT-44403 Kaunas (Lithuania)

    2013-07-15

    Highlights: • Plastical deformation of the shock absorber. • Dynamic testing of the scaled shock absorber. • Dynamic simulation of the shock absorber using finite element method. • Strain-rate evaluation in dynamic analysis. • Variation of displacement, acceleration and velocity during dynamic impact. -- Abstract: The Ignalina Nuclear Power Plant (NPP) has two RBMK-1500 graphite moderated boiling water multi-channel reactors. The Ignalina NPP Unit 1 was shut down at the end of 2004 while Unit 2 has been in operation for over 5 years. After shutdown at the Unit 1 remained spent fuel assemblies with low burn-up depth. In order to reuse these assemblies in the reactor of Unit 2 a special set of equipment was developed. One of the most important items of this set is a container, which is used for the transportation of spent fuel assemblies between the reactors of Unit 1 and Unit 2. A special shock absorber was designed to avoid failure of fuel assemblies in case of hypothetical spent fuel assemblies drop accident during uploading/unloading of spent fuel assemblies to/from container. This shock absorber was examined using scaled experiments and finite element analysis. Static and dynamic investigations of the shock absorber were performed for the estimation and optimization of its geometrical parameters. The objective of this work is the estimation whether the proposed design of shock absorber can fulfil the stopping function of the spent fuel assemblies and is capable to withstand the dynamics load. Experimental testing of scaled shock absorber models and dynamic analytical investigations using the finite element code ABAQUS/Explicit were performed. The simulation model was verified by comparing the experimental and simulation results and it was concluded that the shock absorber is capable to withstand the dynamic load, i.e. successful force suppression function in case of accident.

  20. Gas-gun facility for shock wave research at BARC

    International Nuclear Information System (INIS)

    Gupta, S.C.; Jyoti, G.; Suresh, N.; Sikka, S.K.; Chidambaram, R.; Agarwal, R.G.; Roy, S.; Kakodkar, A.

    1995-01-01

    For carrying out shock-wave experiments on materials, we have built a 63 mm diameter gas-gun facility at our laboratory. It is capable of accelerating projectiles (about half kg in weight) to velocities up to 1 km/s using N 2 and He gases. These on impacting a target generate shock pressures up to 40 GPa, depending upon the impedance of the impactor and the target. The barrel of the gun is slotted so that a keyed projectile can be fired for combined compression- shear studies. Large samples can be shocked (about 60 mm diameter and 5-10 mm thick), with pressures lasting for a few microseconds. The gun is similar in design to the one at Washington State University. A number of diagnostic techniques have also been developed. These include measurement of projectile velocity, tilt between the impactor and the target, shock velocity in the target, and time resolved in-material stress wave histories in the shock loaded samples. Recovery capsules have also been made to retrieve shocked samples on unloading, which are then analysed using microscopic techniques like x-ray diffraction, Raman and electron microscopy. The gun has been performing well and has already been used for a few phase transition studies. (author). 73 refs., 42 figs

  1. Millisecond-period meltdown experiments on prompt-burst effects and molten-tin-water dropping experiments

    International Nuclear Information System (INIS)

    Wright, R.W.; Coats, R.L.; Schmidt, T.R.; Arakeri, V.H.

    1976-01-01

    The U.S. Nuclear Regulatory Commission has initiated a program of confirmatory research for the safety assessment of LMFBR plants. In the sodium-fuel interactions area, this research includes a series of real-time in-pile experiments on the pressure and work potential of prompt-burst excursions as well as laboratory dropping experiments with molten tin and water. The in-pile experiments are performed by Sandia Laboratories in the Annular Core Pulse Reactor (ACPR), which has a minimum period of 1.3 milliseconds. These single-pin experiments are performed in a piston-loaded, stagnent-sodium autoclave, that is conceptually similar to the one used in the S-11 TREAT test. Unlike the S-11 test, however, realistic radial temperature profiles are obtained in the fuel, the cladding, and the sodium by pre-pulsing the reactor about 1/2 second before the main pulse. A series of preparatory runs have been made with helium-filled capsules and at low energy with sodium-filled capsules. The first significant fuel-coolant interaction run is scheduled for late March 1976. This will be a double-pulsed run at 2700 j/gm UO 2 . A continuing series of experiments is planned with oxide and advanced fuels in both fresh and irradiated form. In molten-tin-water dropping experiments at UCLA, microsecond duration multi-flash photography has been used for event diagnostics. Transition or nucleate boiling was found to trigger energetic interactions or vapor explosions. Temperature stratification in the water was found to reduce the threshold tin temperature necessary to produce vapor explosions below that the predicted by the coolant homogeneous nucleation hypothesis. Interaction zone growth times of a few msec. were measured. (auth.)

  2. Millisecond-Period Meltdown Experiments on Prompt - Burst Effects and Molten-Tin-Water Dropping Experiments

    International Nuclear Information System (INIS)

    Wright, R.W.; Coats, R.L.; Schmidt, T.R.; Arakeri, V.H.

    1976-01-01

    The U.S. Nuclear Regulatory Commission has initiated a program of confirmatory research for the safety assessment of LMFBR plants. In the sodium-fuel interactions area, this research includes a series of real-time in-pile experiments on the pressure and work potential of prompt-burst excursions as well as laboratory dropping experiments with molten tin and water. The in-pile experiments are performed by Sandia Laboratories in the Annular Core Pulse Reactor (ACPR), which has a minimum period of 1.3 milliseconds. These single-pin experiments are performed in a piston-loaded, stagnant-sodium autoclave, that is conceptually similar to the one used in the S-11 TREAT test. Unlike the S-11 test, however, realistic radial temperature profiles are obtained in the fuel, the cladding, and the sodium by pre-pulsing the reactor about 1/2 second before the main pulse. A series of preparatory runs have been made with helium-filled capsules and at low energy with sodium-filled capsules. The first significant fuel-coolant interaction run is scheduled for late March 1976. This will be a double-pulsed run at 2700 j/gm UO 2 . A continuing series of experiments is planned with oxide and advanced fuels in both fresh and irradiated form. In molten-tin-water dropping experiments at UCLA, microsecond duration multi-flash photography has been used for event diagnostics. Transition or nucleate boiling was found to trigger energetic interactions or vapor explosions. Temperature stratification in the water was found to reduce the threshold tin temperature necessary to produce vapor explosions below that the predicted by the coolant homogeneous nucleation hypothesis. Interaction zone growth times of a few msec were measured

  3. NASA Goddard Space Flight Center Tin Whisker (and Other Metal Whisker) Homepage

    Science.gov (United States)

    Brusse, Jay; Sampson, Mike; Leidecker, Henning; Kadesch, Jong

    2004-01-01

    This website provides information about tin whiskers and related research. The independent research performed during the past 50+ years is so vast that it is impractical to cover all aspects of tin whiskers in this one resource. Therefore, the absence of information in this website about a particular aspect of tin whiskers should NOT be construed as evidence of absence.

  4. Electrospun polyacrylonitrile nanofibers loaded with silver nanoparticles by silver mirror reaction

    International Nuclear Information System (INIS)

    Shi, Yongzheng; Li, Yajing; Zhang, Jianfeng; Yu, Zhongzhen; Yang, Dongzhi

    2015-01-01

    The silver mirror reaction (SMR) method was selected in this paper to modify electrospun polyacrylonitrile (PAN) nanofibers, and these nanofibers loaded with silver nanoparticles showed excellent antibacterial properties. PAN nanofibers were first pretreated in AgNO 3 aqueous solution before the SMR process so that the silver nanoparticles were distributed evenly on the outer surface of the nanofibers. The final PAN nanofibers were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), TEM-selected area electron diffraction (SAED), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). SEM, TEM micrographs and SAED patterns confirmed homogeneous dispersion of the silver nanoparticles which were composed of monocrystals with diameters 20–30 nm. EDS and XRD results showed that these monocrystals tended to form face-centered cubic single silver. TGA test indicated that the nanoparticles loaded on the nanofibers reached above 50 wt.%. This material was also evaluated by the viable cell-counting method. The results indicated that PAN nanofibers loaded with silver nanoparticles exhibited excellent antimicrobial activities against gram-negative Escherichia coli (E. coli), gram-positive Staphylococcus aureus (S. aureus) and the fungus Monilia albicans. Thus, this material had many potential applications in biomedical fields. - Highlights: • Silver mirror reaction was used to prepare nanofibers loaded with silver nanoparticles. • The SAED patterns demonstrated the monocrystallinity of silver nanocrystals. • The XRD results showed nanoparticles tended to be face-centered cubic single silver. • The material showed excellent antimicrobial activities against bacteria and fungi

  5. [Identification of Dens Draconis and Os Draconis by XRD method].

    Science.gov (United States)

    Chen, Guang-Yun; Wu, Qi-Nan; Shen, Bei; Chen, Rong

    2012-04-01

    To establish an XRD method for evaluating the quality of Os Draconis and Dens Draconis and applying in judgement of the counterfeit. Dens Draconis, Os Draconis and the counterfeit of Os Draconis were analyzed by XRD. Their diffraction patterns were clustered analysis and evaluated their similarity degree. Established the analytical method of Dens Draconis and Os Draconis basing the features fingerprint information of the 10 common peaks by XRD pattern. Obtained the XRD pattern of the counterfeit of Os Draconis. The similarity degree of separate sources of Dens Draconis was high,while the similarity degree of separate sources of Os Draconis was significant different from each other. This method can be used for identification and evaluation of Os Draconis and Dens Draconis. It also can be used for identification the counterfeit of Os Draconis effectively.

  6. Fundamental structure of steady plastic shock waves in metals

    Science.gov (United States)

    Molinari, A.; Ravichandran, G.

    2004-02-01

    The propagation of steady plane shock waves in metallic materials is considered. Following the constitutive framework adopted by R. J. Clifton [Shock Waves and the Mechanical Properties of Solids, edited by J. J. Burke and V. Weiss (Syracuse University Press, Syracuse, N.Y., 1971), p. 73] for analyzing elastic-plastic transient waves, an analytical solution of the steady state propagation of plastic shocks is proposed. The problem is formulated in a Lagrangian setting appropriate for large deformations. The material response is characterized by a quasistatic tensile (compression) test (providing the isothermal strain hardening law). In addition the elastic response is determined up to second order elastic constants by ultrasonic measurements. Based on this simple information, it is shown that the shock kinetics can be quite well described for moderate shocks in aluminum with stress amplitude up to 10 GPa. Under the later assumption, the elastic response is assumed to be isentropic, and thermomechanical coupling is neglected. The model material considered here is aluminum, but the analysis is general and can be applied to any viscoplastic material subjected to moderate amplitude shocks. Comparisons with experimental data are made for the shock velocity, the particle velocity and the shock structure. The shock structure is obtained by quadrature of a first order differential equation, which provides analytical results under certain simplifying assumptions. The effects of material parameters and loading conditions on the shock kinetics and shock structure are discussed. The shock width is characterized by assuming an overstress formulation for the viscoplastic response. The effects on the shock structure of strain rate sensitivity are analyzed and the rationale for the J. W. Swegle and D. E. Grady [J. Appl. Phys. 58, 692 (1985)] universal scaling law for homogeneous materials is explored. Finally, the ability to deduce information on the viscoplastic response of

  7. Fundamental structure of steady plastic shock waves in metals

    International Nuclear Information System (INIS)

    Molinari, A.; Ravichandran, G.

    2004-01-01

    The propagation of steady plane shock waves in metallic materials is considered. Following the constitutive framework adopted by R. J. Clifton [Shock Waves and the Mechanical Properties of Solids, edited by J. J. Burke and V. Weiss (Syracuse University Press, Syracuse, N.Y., 1971), p. 73] for analyzing elastic-plastic transient waves, an analytical solution of the steady state propagation of plastic shocks is proposed. The problem is formulated in a Lagrangian setting appropriate for large deformations. The material response is characterized by a quasistatic tensile (compression) test (providing the isothermal strain hardening law). In addition the elastic response is determined up to second order elastic constants by ultrasonic measurements. Based on this simple information, it is shown that the shock kinetics can be quite well described for moderate shocks in aluminum with stress amplitude up to 10 GPa. Under the later assumption, the elastic response is assumed to be isentropic, and thermomechanical coupling is neglected. The model material considered here is aluminum, but the analysis is general and can be applied to any viscoplastic material subjected to moderate amplitude shocks. Comparisons with experimental data are made for the shock velocity, the particle velocity and the shock structure. The shock structure is obtained by quadrature of a first order differential equation, which provides analytical results under certain simplifying assumptions. The effects of material parameters and loading conditions on the shock kinetics and shock structure are discussed. The shock width is characterized by assuming an overstress formulation for the viscoplastic response. The effects on the shock structure of strain rate sensitivity are analyzed and the rationale for the J. W. Swegle and D. E. Grady [J. Appl. Phys. 58, 692 (1985)] universal scaling law for homogeneous materials is explored. Finally, the ability to deduce information on the viscoplastic response of

  8. Ductile fracture estimation of reactor pressure vessel under thermal shock

    International Nuclear Information System (INIS)

    Takahashi, Jun; Sakai, Shinsuke; Okamura, Hiroyuki

    1990-01-01

    This paper presents a new scheme for the estimation of unstable ductile fracture of a reactor pressure vessel under thermal shock conditions. First, it is shown that the bending moment applied to the cracked section can be evaluated by considering the plastic deformation of the cracked section and the thermal deformation of the shell. As the contribution of the local thermal stress to the J-value is negligible, the J-value under thermal shock can be easily evaluated by using fully plastic solutions for the cracked part. Next, the phenomena of ductile fracture under thermal shock are expressed on the load-versus-displacement diagram which enables us to grasp the transient phenomena visually. In addition, several parametrical surveys are performed on the above diagram concerning the variation of (1) thermal shock conditions, (2) initial crack length, and (3) J-resistance curve (i.e. embrittlement by neutron irradiation). (author)

  9. Synthesis of a smart pH-responsive magnetic nanocomposite as high loading carrier of pharmaceutical agents.

    Science.gov (United States)

    Berah, Razieh; Ghorbani, Mohsen; Moghadamnia, Ali Akbar

    2017-06-01

    To create facile external controlled drug delivery system, a magnetic porous carrier based on Tin oxide nanoparticles was synthesized by an inexpensive and versatile hydrothermal strategy and used for in-vitro process. Magnetic nanocomposites were qualified by Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Vibrational Sample Magnetometer (VSM) and Transmission Electron Microscopy (TEM). Results showed that nanoparticles were synthesized successfully with good dispersion of magnetic nanoparticles in cavity, uniform particle size distribution with average size of 65nm and high magnetization of 33.75 emu/mg. Furthermore, the nano-porosity and magnetism allowed high efficiency and remote controlled drug release. In this study, anti-migraine Sumatriptan was used as drug sample and the effect of drug concentration, Fe/Sn ratio and loading time on drug absorption were investigated. The best result was checked for stability at body temperature and different body pH. The sample with drug concentration of 0.25(mg/ml), Fe/Sn=0.22 and loading time of 1.5h had the highest drug efficiency (70%). Finally, in order to simulate the in vivo process for in-vitro step, Amnion was used and drug diffusion rate was measured in different intervals and different pH values. The result illustrated that after 25h, diffusion reached 65% at pH=2 and 56% at pH=7, and then became constant. Based on the above mentioned results, the carrier has an acceptable in vitro yield and therefore could be chosen for future in vivo researches. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Structural and magnetic studies of tin doped α-Fe{sub 2}O{sub 3} (α-Sn{sub x}Fe{sub 2-x}O{sub 3}) nanoparticles prepared by microwave assisted synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Bindu, K.; Nagaraja, H. S., E-mail: hosakoppa@gmail.com [Material Research Laboratory, Department of Physics, National Institute of Technology Karnataka, Surathkal, Srinivasnagar, Mangalore-575 025, Karnataka (India); Chowdhury, P. [Nanomaterials Research Laboratory, Surface Engineering Division, National Aerospace Laboratories, Council of Scientific and Industrial Research, Bangalore-560 017, Karnataka (India); Ajith, K. M. [Computational Physics Laboratory, Department of Physics, National Institute of Technology Karnataka, Surathkal, Srinivasnagar, Mangalore-575 025, Karnataka (India)

    2016-05-06

    Hematite (α-Fe{sub 2}O{sub 3}) doped with tetravalent ions have potential applications in various fields such as gas sensors, memories, energy storage devices because of their electrical and magnetic properties. Microwave assisted synthesis was used to prepare Tin doped α-Fe{sub 2}O{sub 3} [α-Sn{sub x}Fe{sub 2-x}O{sub 3}]. The structural and morphological studies were investigated using X-ray diffraction (XRD) and Scanning electron microscopy (SEM). XRD patterns revealed that α-Fe{sub 2}O{sub 3} and α-Sn{sub x}Fe{sub 2-x}O{sub 3} were having rhombohedral structure. The compositional study was done by Energy dispersive X-ray Spectroscopy (EDS). The magnetic properties were studied by Vibrating Sample Magnetometry (VSM). Results shows that the prepared samples were found to be antiferromagnetic in nature and the results are discussed in detail.

  11. Tin in canned food: a review and understanding of occurrence and effect.

    Science.gov (United States)

    Blunden, Steve; Wallace, Tony

    2003-12-01

    Tinplate is light gauge, steel sheet or strip, coated on both sides with commercially pure tin and has been used for well over a hundred years as a robust form of food packaging. Altogether, about 25,000 million food cans are produced and filled in Europe per annum, about 20% of these having plain internal (unlacquered) tin-coated steel bodies. Worldwide, the total for food packaging is approximately 80,000 million cans. Tinplate is also extensively used for the production of beverage cans. Europe produces and fills over 15,000 million tinplate beverage cans per annum all of which are internally lacquered. The use of tinplate for food and beverage packaging, will result in some tin dissolving into the food content, particularly when plain uncoated internal surfaces are used. The Provisional Tolerable Weekly Intake for tin is 14 mg/kg body weight and recommended maximum permissible levels of tin in food are typically 250 mg/kg (200 mg/kg UK) for solid foods and 150 mg/kg for beverages. However, the question arises as to whether evidence exists that such elevated levels of tin in food in any way constitute a risk to human health. This review considers the factors affecting the dissolution of tin, the reported measurements/surveys of actual levels of tin in canned foods and the studies and reports of acute (short term) toxicity relating to the ingestion of elevated levels of tin in food products. Chronic studies are mentioned, but are not covered in detail, since the review is mainly concerned with possible effects from the ingestion of single high doses. From published data, there appears to be a small amount of evidence suggesting that consumption of food or beverages containing tin at concentrations at or below 200 ppm has caused adverse gastrointestinal effects in an unknown but possibly small proportion of those exposed. However, the evidence supporting this assertion is derived from reports of adverse effects which offer data that are limited, incomplete or of

  12. Oxidation resistance of TiN, CrN, TiAlN and CrAlN coatings deposited by lateral rotating cathode arc

    International Nuclear Information System (INIS)

    Chim, Y.C.; Ding, X.Z.; Zeng, X.T.; Zhang, S.

    2009-01-01

    In this paper, four kinds of hard coatings, TiN, CrN, TiAlN and CrAlN (with Al/Ti or Al/Cr atomic ratio around 1:1), were deposited on stainless steel substrates by a lateral rotating cathode arc technique. The as-deposited coatings were annealed in ambient atmosphere at different temperatures (500-1000 o C) for 1 h. The evolution of chemical composition, microstructure, and microhardness of these coatings after annealing at different temperatures was systematically analyzed by energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and nanoindentation experiments. The oxidation behaviour and its influence on overall hardness of these four coatings were compared. It was found that the ternary TiAlN and CrAlN coatings have better oxidation resistance than their binary counterparts, TiN and CrN coatings. The Cr-based coatings (CrN and CrAlN) exhibited evidently better oxidation resistance than the Ti-based coatings (TiN and TiAlN). TiN coating started to oxidize at 500 o C. After annealing at 700 o C no N could be detected by EDX, indicating that the coating was almost fully oxidized. After annealed at 800 o C, the coating completely delaminated from the substrate. TiAlN started to oxidize at 600 o C. It was nearly fully oxidized (with little residual nitrogen detected in the coating by EDX) and partially delaminated at 1000 o C. Both CrN and CrAlN started to oxidize at 700 o C. CrN was almost fully oxidized (with little residual nitrogen detected in the coating by EDX) and partially delaminated at 900 o C. The oxidation rate of the CrAlN coating is quite slow. After annealing at 1000 o C, only about 19 at.% oxygen was detected and the coating showed no delamination. The Ti-based (TiN and TiAlN) coatings were not able to retain their hardness at higher temperatures (≥ 700 o C). On the other hand, the hardness of CrAlN was stable at a high level between 33 and 35 GPa up to an annealing temperature of 800 o C and still kept at a comparative high value of

  13. Electrochemical deposition of gold-platinum alloy nanoparticles on an indium tin oxide electrode and their electrocatalytic applications

    Energy Technology Data Exchange (ETDEWEB)

    Song Yan; Ma Yuting; Wang Yuan [Department of Chemistry, Soochow University, Suzhou, Jiangsu 215123 (China); Di Junwei, E-mail: djw@suda.edu.c [Department of Chemistry, Soochow University, Suzhou, Jiangsu 215123 (China); Tu Yifeng [Department of Chemistry, Soochow University, Suzhou, Jiangsu 215123 (China)

    2010-07-01

    Gold-platinum (Au-Pt) hybrid nanoparticles (Au-PtNPs) were successfully deposited on an indium tin oxide (ITO) surface using a direct electrochemical method. The resulting nanoparticles were characterized by scanning electron microscopy (SEM), UV-vis spectroscopy, X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and electrochemical methods. It was found that the size of the Au-PtNPs depends on the number of electrodeposition cycles. Au-PtNPs obtained by 20 electrodeposition cycles had a cauliflower-shaped structure with an average diameter of about 60 nm. These Au-PtNPs exhibited alloy properties. Electrochemical measurements showed that the charge transfer resistivity was significantly decreased for the Au-PtNPs/ITO electrode. Additionally, the Au-PtNPs displayed an electrocatalytic activity for nitrite oxidation and oxygen reduction. The Au-PtNPs/ITO electrodes reported herein could possibly be used as electrocatalysts and sensors.

  14. Effect of strain rate on cavity closure during compression between flat platens using superplastic tin-lead alloy

    International Nuclear Information System (INIS)

    Zaid, A.I.O.; Al-Tamimi, M.M.

    2011-01-01

    Superplasticity is a feature of a material or alloy which allows the material to deform plastically to an extremely large strain at low values of stress under certain loading conditions of strain rate and temperature. Eutectic tin-lead alloy is a practical material for research investigations as it possesses a superplastic behavior at room temperature and low strain rate which makes it a useful tool in simulating the ordinary engineering materials at high strain rate and temperature. This alloy has been extensively used as a model material to simulate behavior of engineering materials at high strain rates and temperatures. In this paper, superplastic tin-lead alloy was used at room temperature to simulate the closure of cavities in steels at high temperatures in the hot region under dynamic loading (high strain rate) under the effect of compressive loads using flat platens (open dies). Hollow specimens having different values of bore diameter (D/sub b/) to outer diameter (D/sub out/), of the same height and volume were investigated under different values of height reduction percentages ranging from 20% to 80% , and the percentage of cavity closure at each reduction percentage was determined. It was found that the cavity closure percentage increases or decreases at slow rate for reduction percentage in height less than 40% and increases more rapidly for reduction percentages in height above this value. Furthermore, specimens having smaller values of ratio (D/sub b//D/sub out/) resulted in higher percentage of cavity closure than specimens having higher ratios at the same value of reduction in height percentage. Complete cavity closure has occurred in specimens having the ratios of 0.1 and 0.2 at 75% reduction in height. (author)

  15. Laser shock ignition of porous silicon based nano-energetic films

    International Nuclear Information System (INIS)

    Plummer, A.; Gascooke, J.; Shapter, J.; Kuznetsov, V. A.; Voelcker, N. H.

    2014-01-01

    Nanoporous silicon films on a silicon wafer were loaded with sodium perchlorate and initiated using illumination with infrared laser pulses to cause laser thermal ignition and laser-generated shock waves. Using Photon Doppler Velocimetry, it was determined that these waves are weak stress waves with a threshold intensity of 131 MPa in the silicon substrate. Shock generation was achieved through confinement of a plasma, generated upon irradiation of an absorptive paint layer held against the substrate side of the wafer. These stress waves were below the threshold required for sample fracturing. Exploiting either the laser thermal or laser-generated shock mechanisms of ignition may permit use of pSi energetic materials in applications otherwise precluded due to their environmental sensitivity

  16. Laser shock ignition of porous silicon based nano-energetic films

    Energy Technology Data Exchange (ETDEWEB)

    Plummer, A.; Gascooke, J.; Shapter, J. [School of Chemical and Physical Sciences, Flinders University, 5042, Bedford Park (Australia); Centre of Expertise in Energetic Materials (CEEM), Bedford Park (Australia); Kuznetsov, V. A., E-mail: nico.voelcker@unisa.edu.au, E-mail: Valerian.Kuznetsov@dsto.defence.gov.au [School of Chemical and Physical Sciences, Flinders University, 5042, Bedford Park (Australia); Centre of Expertise in Energetic Materials (CEEM), Bedford Park (Australia); Weapons and Combat Systems Division, Defence Science and Technology Organisation, Edinburgh 5111 (Australia); Voelcker, N. H., E-mail: nico.voelcker@unisa.edu.au, E-mail: Valerian.Kuznetsov@dsto.defence.gov.au [Mawson Institute, University of South Australia, 5095, Mawson Lakes (Australia)

    2014-08-07

    Nanoporous silicon films on a silicon wafer were loaded with sodium perchlorate and initiated using illumination with infrared laser pulses to cause laser thermal ignition and laser-generated shock waves. Using Photon Doppler Velocimetry, it was determined that these waves are weak stress waves with a threshold intensity of 131 MPa in the silicon substrate. Shock generation was achieved through confinement of a plasma, generated upon irradiation of an absorptive paint layer held against the substrate side of the wafer. These stress waves were below the threshold required for sample fracturing. Exploiting either the laser thermal or laser-generated shock mechanisms of ignition may permit use of pSi energetic materials in applications otherwise precluded due to their environmental sensitivity.

  17. Partitioning of a scaled shallow-buried near-field blast load

    CSIR Research Space (South Africa)

    Reinecke, J David

    2015-07-01

    Full Text Available and target force response to a shallow and deep buried blast loads and the initial loading phase contribution to the blast load were quantified. There is no separate precursor air shock for shallow buried blast load and the initial loading phase impulse... stream_source_info Reinecke_2015.pdf.txt stream_content_type text/plain stream_size 24459 Content-Encoding UTF-8 stream_name Reinecke_2015.pdf.txt Content-Type text/plain; charset=UTF-8 Partitioning of a Scaled Shallow...

  18. Data derived from constitutive laws for description of shock wave propagation in concrete. Final report

    International Nuclear Information System (INIS)

    Eibl, J.; Ockert, J.

    1994-01-01

    Especially the need to design safe reactor containments, but also the necessity to protect facilities and human beings against impacts induced secondarily by explosions and detonations, demand simulations and design calculations of concrete under shock wave loading. The necessary computer codes are available, but the relevant constitutive laws for concrete with volumetric pressures up to more than 10000 MPa are lacking. Therefore shock wave tests have been carried out to develop such constitutive laws by loading concrete slabs with contact explosions. By the use of hot-molded carbon composition resistors shock waves propagating through the slab were measured. Pressures up to 13900 MPa were registered. Additionally shock wave velocities were determined from the different arrival times of the wave at the gages. By these two measured values and the conservation equations of mass and momentum the needed p-V relationship, the so called Hugoniot-Curve, was established up to 13900 MPa. Using the theory of Mie-Grueneisen and the so called P-α model the Hugoniot-Curve was extended to the equation of state for concrete. In a first step the deviatoric part of the constitutive law was attached from own static experiments considering the existing knowledge of strain rate effects since relevant dynamic tests under extreme loads are not available. With this constitutive law the analysis of the experiments then was backward verified in detail. (orig.) [de

  19. Determination of tungsten and tin ions after preconcentration by flotation

    International Nuclear Information System (INIS)

    Dietze, U.; Kunze, S.

    1990-01-01

    A highly sensitive and selective combined method of flotation followed by spectrophotometry/d.c. polarography for the determination of tungsten and tin ions in acid and alkaline waste waters and hydrometallurgical solutions is presented here. Both kinds of ions are coprecipitated in the analyte solution with zirconium hydroxide after addition of ZrOCl 2 solution and ammonia. Afterwards, the collector precipitate is separated from the aqueous phase and preconcentrated by flotation for which sodium oleate and a frother are added. The precipitate is dissolved in a small amount of acid, with the organic reagents being destroyed by oxidation. The enrichment factor of the proposed technique is 100, with variations possible. Recovery is 94 % for tungsten and 99 % for tin. Spectrophotometry of the thiocyanate complex and d.c. polarography are applied as determination techniques for tungsten and tin, respectively. Detection limits attainable by this technique are 6 ng.ml -1 for tungsten and 5 ng.ml -1 for tin for the initial sample. (Authors)

  20. Styrene–tin (IV) phosphate nanocomposite for photocatalytic degradation of organic dye in presence of visible light

    Energy Technology Data Exchange (ETDEWEB)

    Rathore, Bhim Singh [School of Chemistry, Shoolini University, Solan 173 212, Himachal Pradesh (India); Department of Chemistry, Government P.G. College, Solan 173 212, Himachal Pradesh (India); Pathania, Deepak, E-mail: dpathania74@gmail.com [School of Chemistry, Shoolini University, Solan 173 212, Himachal Pradesh (India)

    2014-09-01

    Highlights: • Styrene–tin (IV) phosphate nanocomposite (ST/TPNC) ion exchanger was chemically prepared by simple sol–gel method at pH 0–1. • ST/TPNC exhibited higher ion exchange capacity as compared to its inorganic component. • ST/TPNC retained about 35.5% of the initial value of ion exchange capacity after heating up to 400 °C. • ST/TPNC was used as efficient photocatalyst for the degradation of MB dye from aqueous system in the presence of solar light. • The pH titrations studies confirmed the monofunctional strong cationic nature of ST/TPNC. - Abstract: Styrene–tin (IV) phosphate nanocomposite (ST/TPNC) ion exchanger was used as efficient photocatalyst for the degradation of methylene blue dye from aqueous system in the presence of solar light. ST/TPNC exhibited a high efficiency in heterogeneous photocatalytic process for the removal of MB from the water system. The degradation efficiency after 2 h illumination was 80%. The degradation of MB follows the pseudo-first-order kinetics with rate constant 0.00702 min{sup −1}. The nanocomposite ion exchanger was explored for its ion exchange capacity, pH titration, elution behavior, elution concentration and distribution coefficient (K{sub d}). ST/TPNC exhibited a higher ion exchange capacity (1.83 meg/g) compared to its inorganic counterpart (0.55 meg/g). ST/TPNC was characterized using some techniques such as Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and thermogravimetric analysis (TGA)

  1. Modeling elastic wave propagation in kidney stones with application to shock wave lithotripsy.

    Science.gov (United States)

    Cleveland, Robin O; Sapozhnikov, Oleg A

    2005-10-01

    A time-domain finite-difference solution to the equations of linear elasticity was used to model the propagation of lithotripsy waves in kidney stones. The model was used to determine the loading on the stone (principal stresses and strains and maximum shear stresses and strains) due to the impact of lithotripsy shock waves. The simulations show that the peak loading induced in kidney stones is generated by constructive interference from shear waves launched from the outer edge of the stone with other waves in the stone. Notably the shear wave induced loads were significantly larger than the loads generated by the classic Hopkinson or spall effect. For simulations where the diameter of the focal spot of the lithotripter was smaller than that of the stone the loading decreased by more than 50%. The constructive interference was also sensitive to shock rise time and it was found that the peak tensile stress reduced by 30% as rise time increased from 25 to 150 ns. These results demonstrate that shear waves likely play a critical role in stone comminution and that lithotripters with large focal widths and short rise times should be effective at generating high stresses inside kidney stones.

  2. Influence of Amang (Tin Tailing) on Geotechnical Properties of Clay Soil

    International Nuclear Information System (INIS)

    Zulfahmi, A.R.; Zuhairi, W.Y.W.; Raihan, M.T.; Sahibin, A.R.; Razi, I.W.M.; Tukimat, L.; Syakireen, Z.S.N.; Noorulakma, A.

    2012-01-01

    Amang or tin tailing is commonly found in the vicinity of disused mining area and responsible in downgrading the water quality, landscape and mechanical behaviour of soils. It was generated from extraction process of separating valuable metal from particular ore. This paper presents the geotechnical characteristics of amang-contaminated clay soil. The geotechnical properties of uncontaminated soils were studied in order to compare to that of amang contaminated soils. The base soil used in this study represents completely weathered horizon of meta sedimentary rock. Meanwhile, tin tailing sample was taken from the disused mine at Sungai Lembing, Pahang. The geotechnical characterisations of base soil and contaminated soils were determined based on consistency index, compaction behaviour, hydraulic conductivity and undrained shear strength (UU tests). Contaminated soil samples were prepared by adding 5, 10 and 20 % of tailing, based on dry weigh of the studied base soil. The results from the particle size distribution analysis showed that residual soil from meta sedimentary rock comprised 42.6 % clay, 32.2 % silt and 25.2 % sand whilst tailing was dominated by 98 % of sand fraction. XRD analysis indicated the presence of quartz, kaolinite and muscovite minerals in the studied soil. The specific gravity of soil used is 2.67 and the pH is 3.88. Tailing found to have higher specific gravity of 3.37. The consistency index of contaminated soils showed that liquid limit, wL and plastic limit, wP decreased with the increase in the percentage of tailing added to the soil samples. The value of maximum dry density, ρ dry max increased while optimum moisture content decreased due to the increase in tailing content in soil sample. The permeability of contaminated soil also increased with the increase in tailing contents ranged from 19.8 cm/ hr to 23.8 cm/ hr. The undrained shear strength, Cu, of contaminated soil decreased from 646 kPa (5 % of tailing) to 312 kPa (20 % of

  3. Transparent and Flexible Zinc Tin Oxide Thin Film Transistors and Inverters using Low-pressure Oxygen Annealing Process

    Science.gov (United States)

    Lee, Kimoon; Kim, Yong-Hoon; Kim, Jiwan; Oh, Min Suk

    2018-05-01

    We report on the transparent and flexible enhancement-load inverters which consist of zinc tin oxide (ZTO) thin film transistors (TFTs) fabricated at low process temperature. To control the electrical characteristics of oxide TFTs by oxygen vacancies, we applied low-pressure oxygen rapid thermal annealing (RTA) process to our devices. When we annealed the ZTO TFTs in oxygen ambient of 2 Torr, they showed better electrical characteristics than those of the devices annealed in the air ambient of 760 Torr. To realize oxide thin film transistor and simple inverter circuits on flexible substrate, we annealed the devices in O2 of 2 Torr at 150° C and could achieve the decent electrical properties. When we used transparent conductive oxide electrodes such as indium zinc oxide (IZO) and indium tin oxide (ITO), our transparent and flexible inverter showed the total transmittance of 68% in the visible range and the voltage gain of 5. And the transition voltage in voltage transfer curve was located well within the range of operation voltage.

  4. Antimicrobial, Mechanical and Thermal Studies of Silver Particle-Loaded Polyurethane

    Directory of Open Access Journals (Sweden)

    Deepen Paul

    2013-12-01

    Full Text Available Silver-particle-incorporated polyurethane films were evaluated for antimicrobial activity towards two different bacteria: Escherichia coli (E. coli and Staphylococcus aureus (S. aureus. Distributed silver particles sourced from silver nitrate, silver lactate and preformed silver nanoparticles were mixed with polyurethane (PU and variously characterized by field emission scanning electron microscopy (FESEM, fourier transform infra-red (FTIR spectroscopy, X-ray diffraction (XRD and contact angle measurement. Antibacterial activity against E.coli was confirmed for films loaded with 10% (w/w AgNO3, 1% and 10% (w/w Ag lactate and preformed Ag nanoparticles. All were active against S. aureus, but Ag nanoparticles loaded with PU had a minor effect. The apparent antibacterial performance of Ag lactate-loaded PU is better than other Ag ion-loaded films, revealed from the zone of inhibition study. The better performance of silver lactate-loaded PU was the likely result of a porous PU structure. FESEM and FTIR indicated direct interaction of silver with the PU backbone, and XRD patterns confirmed that face-centred cubic-type silver, representative of Ag metal, was present. Young’s modulus, tensile strength and the hardness of silver containing PU films were not adversely affected and possibly marginally increased with silver incorporation. Dynamic mechanical analysis (DMA indicated greater thermal stability.

  5. The Pneumatic Actuators As Vertical Dynamic Load Simulators On Medium Weighted Wheel Suspension Mechanism

    Science.gov (United States)

    Ka'ka, Simon; Himran, Syukri; Renreng, Ilyas; Sutresman, Onny

    2018-02-01

    Almost all of road damage can be caused by dynamic loads of vehicles that fluctuate according to the type of vehicle that passes through. This study aims to calculate the vertical dynamic load of the vehicle actually occurs on road construction by the mechanism of vehicle wheel suspension. Pneumatic cylinders driven by pressurized air directly load the spring and shock absorber installed on the wheels of the vehicle. The load fluctuations of the medium weight categorized vehicles are determined by the regulation of the amount of pressurized air that enters into the pneumatic cylinder chamber, pushing the piston and connecting rods. The displacement that occurs during compression on the spring and shock absorber, is substituted into the equation of vehicle dynamic load while taking into account the spring stiffness constant, and the fluid or damper gas coefficient. The results show that the magnitude of the displacement when the compression force works has significant influences to the amount of vertical dynamic load of the vehicle that overlies the road construction. The presence of dynamic load of vehicles that fluctuates and repeats, also affects on the reduction of road ability to receive the load. Experimental results using pneumatic actuators instead of real dynamic vehicle loads illustrate the characteristics of the relationship between work pressure and dynamic load. If the working pressure of P2 (bar) is greater, the vertical dynamic load Ft (N) that overloads the road structure is also greater. The associate graphs show that the shock absorber has a greater ability to reduce dynamic load vertically that burden the road structure when compared with the ability of screw spring.

  6. XRD, TEM, and thermal analysis of Arizona Ca-montmorillonites modified with didodecyldimethylammonium bromide.

    Science.gov (United States)

    Sun, Zhiming; Park, Yuri; Zheng, Shuilin; Ayoko, Godwin A; Frost, Ray L

    2013-10-15

    An Arizona SAz-2 calcium montmorillonite was modified by a typical dialkyl cationic surfactant (didodecyldimethylammonium bromide, abbreviated to DDDMA) through direct ion exchange. The obtained organoclays were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), high-resolution thermogravimetric analysis (HR-TG), and infrared emission spectroscopy (IES). The intercalation of surfactants greatly increased the basal spacing of the interlayers and the conformation arrangement of the loaded surfactant were assessed based on the XRD and TEM measurements. This work shows that the dialkyl surfactant can be directly intercalated into the montmorillonite without first undergoing Na(+) exchange. Moreover, the thermal stability of organoclays and the different arrangements of the surfactant molecules intercalated in the SAz-2 Ca-montmorillonite were determined by a combination of TG and IES techniques. The detailed conformational ordering of different intercalated surfactants under different conditions was also studied. The surfactant molecule DDDMA has proved to be thermally stable even at 400°C which indicates that the prepared organoclay is stable to significantly high temperatures. This study offers new insights into the structure and thermal stabilities of SAz-2 Ca-montmorillonite modified with DDDMA. The experimental results also confirm the potential applications of organic SAz-2 Ca-montmorillonites as adsorbents and polymer-clay nanocomposites. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. 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

  8. 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

  9. Cardiogenic shock. Current concepts in management.

    Science.gov (United States)

    Balakumaran, K; Hugenholtz, P G

    1986-10-01

    This article presents a categorisation of circulatory shock and discusses the causes, haemodynamics, and clinical recognition of cardiogenic shock. The first step in the management strategy in cardiogenic shock is to guide the patient from the state of shock to one of managed haemodynamic stability. The therapeutic manoeuvres of this first step constitute the management tactics, which can be grouped under 3 general headings: (a) making the most of a malfunctioning heart; (b) improving the state of the heart; and (c) reducing the demands on the heart. In order to make the most of the heart, i.e. to get the highest possible output at the lowest possible cost, clinicians need to use their judgement in stimulating an overtaxed heart on the one hand, and in manipulating the loads on it (the preload and afterload) on the other, for although these methods may be advantageous, they are not without their pitfalls. Efforts to improve the state of the heart often necessitate surgical (e.g. mitral valve replacement) or semisurgical (e.g. coronary angiography and recanalisation) techniques, although intravenous antithrombotic agents may achieve comparable results in a few cases at the bedside. Reducing the demands on the heart is an active process involving the takeover of at least a part of the work of the heart by ancillary devices such as the intra-aortic balloon pump, and of the work of breathing by intubation and artificial ventilation. The individuality of each case of cardiogenic shock emphasises the need for empirical modulation of therapy based on feedback information obtained by haemodynamic monitoring.

  10. The influence of the admixture of the fullerene C60 on the strength properties of aluminum and copper under shock-wave loading

    International Nuclear Information System (INIS)

    Bezruchko, G S; Razorenov, S V; Popov, M Y

    2014-01-01

    Hugoniot elastic limit (HEL) and dynamic (spall) strength measurements of pressed aluminum and copper samples with an admixture of the fullerene C60 with 2-5 wt% under shock-wave loading were carried out. The peak pressure in the shock-wave was equal to 6 GPa. The measurements of the elastic-plastic and strength properties were based on the recording and the subsequent analysis of the sample free surface velocity histories, recorded by Velocity Interferometric System for Any Reflection (VISAR). It was found that the admixture of 5 wt% fullerene in aluminum samples led to an increase of the Hugoniot elastic limit for aluminum samples by a factor of ten. The copper samples with the admixture of 2 wt% fullerene also demonstrated an increase of the Hugoniot elastic limit in comparison with commercial copper. The measured values of the Hugoniot elastic limit were equal to 0.82-1.56 GPa for aluminum samples and 1.35-3.46 GPa for copper samples, depending on their porosity. As expected, the spall strength of the samples with fullerene decreased by about three times in comparison with the undoped samples as a result of the influence of the solid fullerene particles which were concentrators of tension stresses in the material under dynamic fracture.

  11. Electrochemical lithiation/delithiation of SnP₂O₇ observed by in situ XRD and ex situ⁷Li/³¹P NMR, and ¹¹⁹Sn Mössbauer spectroscopy.

    Science.gov (United States)

    Bezza, Ilham; Kaus, Maximilian; Riekehr, Lars; Pfaffmann, Lukas; Doyle, Stephen; Indris, Sylvio; Ehrenberg, Helmut; Solhy, Abderrahim; Saadoune, Ismael

    2016-04-21

    SnP2O7 was prepared by a sol-gel route. The structural changes of tin pyrophosphate during the electrochemical lithiation were followed by using in situ XRD measurements that reveal the existence of a crystalline phase at the beginning of the discharge process. Nevertheless, it becomes amorphous after the full discharge as a result of a conversion reaction leading to the formation of LixSny alloys. The electrochemical tests show a high capacity with high retention upon cycling. To better understand the reaction mechanism of SnP2O7 with Li, several techniques were applied, such as ex situ(119)Sn Mössbauer and ex situ(7)Li and (31)P NMR spectroscopies with which we can follow the changes in the local environment of each element during cycling.

  12. A study of shock mitigating materials in a split Hopkinson bar configuration. Phase 2

    International Nuclear Information System (INIS)

    Bateman, V.I.; Brown, F.A.; Hansen, N.R.

    1997-01-01

    Sandia National Laboratories (SNL) designs mechanical systems with electronics that must survive high shock environments. These mechanical systems include penetrators that must survive soil and rock penetration, nuclear transportation casks that must survive transportation environments, and laydown weapons that must survive delivery impact. These mechanical systems contain electronics that may operate during and after the high shock environment and that must be protected from the high shock environments. A study has been started to improve the packaging techniques for the advanced electronics utilized in these mechanical systems because current packaging techniques are inadequate for these sensitive electronics. In many cases, it has been found that the packaging techniques currently used not only do not mitigate the shock environment but actually amplify the shock environment. An ambitious goal for this packaging study is to avoid amplification and possibly attenuate the shock environment before it reached the electronics contained in the various mechanical systems. Here, a study to compare two thickness values, 0.125 and 0.250 in. of five materials, GE RTV 630, HS II Silicone, Polysulfide Rubber, Sylgard 184, and Teflon for their shock mitigating characteristics with a split Hopkinson bar configuration has been completed. The five materials have been tested in both unconfined and confined conditions at ambient temperature and with two applied loads of 750 με peak (25 fps peak) with a 100 micros duration, measured at 10% amplitude, and 1500 με peak (50 fps peak) with a 100 micros duration, measured at 10% amplitude. The five materials have been tested at ambient, cold (-65 F), and hot (+165 F) for the unconfined condition with the 750 με peak (25 fps peak) applied load. Time domain and frequency domain analyses of the split Hopkinson bar data have been performed to compare how these materials lengthen the shock pulse, attenuate the shock pulse, reflect high

  13. Radiation levels and countermeasure research on radiological protection in tin mine in china

    International Nuclear Information System (INIS)

    Yang Fengfang; Yuan Yongling

    2010-01-01

    Objective: To study the distribution of radiation level in our nation's tin mine, therefore comes up with proposals on radiological protection and provide scientific evidence on how to protect lives and health of worker underground in tin mine. Methods: To get the radiation level of the underground workplaces in tin mine by analysis of research papers and the measuring results from on-scene investigations. Results: Majority of the absorbed dose rates of γ radiation in the air of underground workplaces in tin mine falls within the range of radiation levels of normal background. Earlier, the typical values of radon concentration and potential alpha energy concentration of radon daughters in the air of underground workplaces in tin mine are 3.12 kBq/m 3 and 5.61 μJ/m 3 respectively. Now, radon concentration and potential alpha energy concentration of radon daughters in the air of underground workplaces in majority of tin mine are lower than 1000 Bq/m 3 and 3.57 μJ/m 3 . Conclusion: For these tin mine workers with an average of annual effective dose greater than 1 mSv or these of their specific activity for natural uranium in materials are greater than 1 Bq/g need to have regulation of radiological protection. The control limits for the radon concentration and the potential alpha energy concentration of radon daughters and the absorbed dose rates of γ radiation in the air of underground workplaces in tin mine are 1000 Bq/m3, 3.57 μJ/m 3 and 1 μGy/h respectively. The administrative individual dose for workers working under the ground of tin mine is 10 mSv/a. If a worker's total annual effective dose is greater than 10 mSv, he/she should be considered as radioactive worker. (authors)

  14. PCBs with immersion tin finish - some experiences with lead-free reflow process

    Energy Technology Data Exchange (ETDEWEB)

    Bukat, K.; Koziol, G.; Sitek, J.; Borecki, J.; Hackiewicz, H. [Tele and Radio Research Inst., Warsaw (Poland); Merkle, H.; Schroeder, S. [Ormecon Chemie GmbH and Co. KG, Ammersbek (Germany); Girulska, A.; Gardela, K. [Eldos Sp. z o.o., Wroclaw (Poland)

    2004-07-01

    Substitution of lead-free solders in electronic assemblies requires changes in the conventional SnPb finishes of PCBs. The Craft project ''PRINT'' objectives respond to this challenge. Its main goal is to develop and implement the new technology of high solderability immersion tin for printed circuit boards at small and medium enterprises. The subject of the research was organic based immersion tin coating which would fulfil demands of SMT. In the paper the results of reflow soldering process on PCBs covered by Ormecon registered immersion tin finish with using lead-free solder pastes will be described. Solderability of tin coating as well as wettability of lead-free solder paste will be presented. (orig.)

  15. Shock waves in P-bar target

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Zhijing; Anderson, K.

    1991-11-01

    The deposition of large amount of beam energy in short time will cause high temperature and pressure in the center of P-bar Target, and this disturbance will propagate outwards as a shock wave. Shock wave induced material changes which are of our concern include void growth and accompanying density decrease which will decrease antiproton yield, and crack formation and fracture as was observed in tungsten target which will destroy the integrity of the target. Our objective is to analyze the shock wave behavior in the target, optimize its design so that the destructive effects of shock wave can be minimized, the integrity of the target can be maintained, and a reasonably high yield of antiproton production can be achieved. In this report we put together some results of our analysis of a cylindrical copper target. We hope that it will provide a general overview of the shock wave phenomena in the target, establish a basis for further research, and facilitate the target design. First, energy deposition data are analyzed, and it is justified that as an approximation, the problem can be treated as axi-symmetric. The average data therefore are used as energy profile, however, the maximum energy deposition are still used as the peak value. Next some basic estimations are made as to what temperature and pressure can reach at present level of energy deposition. Then some characteristics of wave propagation in a thermal shock loaded solid are illustrated with a one-dimensional model. Since there is no analytical solution available for cylindrical geometry, our understanding of the problem relies on numerical model, which are performed via finite element package ANSYS. results of numerical analysis are summarized, sources of potential danger are identified, and design ideas to minimize the damage are proposed.

  16. Shock waves in P-bar target

    International Nuclear Information System (INIS)

    Tang, Zhijing; Anderson, K.

    1991-11-01

    The deposition of large amount of beam energy in short time will cause high temperature and pressure in the center of P-bar Target, and this disturbance will propagate outwards as a shock wave. Shock wave induced material changes which are of our concern include void growth and accompanying density decrease which will decrease antiproton yield, and crack formation and fracture as was observed in tungsten target which will destroy the integrity of the target. Our objective is to analyze the shock wave behavior in the target, optimize its design so that the destructive effects of shock wave can be minimized, the integrity of the target can be maintained, and a reasonably high yield of antiproton production can be achieved. In this report we put together some results of our analysis of a cylindrical copper target. We hope that it will provide a general overview of the shock wave phenomena in the target, establish a basis for further research, and facilitate the target design. First, energy deposition data are analyzed, and it is justified that as an approximation, the problem can be treated as axi-symmetric. The average data therefore are used as energy profile, however, the maximum energy deposition are still used as the peak value. Next some basic estimations are made as to what temperature and pressure can reach at present level of energy deposition. Then some characteristics of wave propagation in a thermal shock loaded solid are illustrated with a one-dimensional model. Since there is no analytical solution available for cylindrical geometry, our understanding of the problem relies on numerical model, which are performed via finite element package ANSYS. results of numerical analysis are summarized, sources of potential danger are identified, and design ideas to minimize the damage are proposed

  17. 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.

  18. Electrochemical migration of tin in electronics and microstructure of the dendrites

    Energy Technology Data Exchange (ETDEWEB)

    Minzari, Daniel, E-mail: dmin@mek.dtu.d [Section for Materials and Surface Technology, Department for Mechanical Engineering, Technical University of Denmark (Denmark); Grumsen, Flemming Bjerg; Jellesen, Morten S.; Moller, Per; Ambat, Rajan [Section for Materials and Surface Technology, Department for Mechanical Engineering, Technical University of Denmark (Denmark)

    2011-05-15

    Graphical abstract: The electrochemical migration of tin in electronics forms dendritic structures, consisting of a metallic tin core, which is surrounded by oxide layers having various thickness. Display Omitted Research highlights: Electrochemical migration occurs if two conductors are connected by condensed moisture. Metallic ions are dissolved and grow in a dendritic structure that short circuit the electrodes. The dendrite consists of a metallic tin core with oxide layers of various thickness surrounding. Detailed microstructure of dendrites is investigated using electron microscopy. The dendrite microstructure is heterogeneous along the growth direction. - Abstract: The macro-, micro-, and nano-scale morphology and structure of tin dendrites, formed by electrochemical migration on a surface mount ceramic chip resistor having electrodes consisting of tin with small amounts of Pb ({approx}2 wt.%) was investigated by scanning electron microscopy and transmission electron microscopy including Energy dispersive X-ray spectroscopy and electron diffraction. The tin dendrites were formed under 5 or 12 V potential bias in 10 ppm by weight NaCl electrolyte as a micro-droplet on the resistor during electrochemical migration experiments. The dendrites formed were found to have heterogeneous microstructure along the growth direction, which is attributed to unstable growth conditions inside the micro-volume of electrolyte. Selected area electron diffraction showed that the dendrites are metallic tin having sections of single crystal orientation and lead containing intermetallic particles embedded in the structure. At certain areas, the dendrite structure was found to be surrounded by an oxide crust, which is believed to be due to unstable growth conditions during the dendrite formation. The oxide layer was found to be of nanocrystalline structure, which is expected to be formed by the dehydration of the hydrated oxide originally formed in solution ex-situ in ambient air.

  19. Preparation and photovoltaic properties of CdS quantum dot-sensitized solar cell based on zinc tin mixed metal oxides.

    Science.gov (United States)

    Cao, Jiupeng; Zhao, Yifan; Zhu, Yatong; Yang, Xiaoyu; Shi, Peng; Xiao, Hongdi; Du, Na; Hou, Wanguo; Qi, Genggeng; Liu, Jianqiang

    2017-07-15

    The present study reports a new type of quantum dot sensitized solar cells (QDSSCs) using the zinc tin mixed metal oxides (MMO) as the anode materials, which were obtained from the layered double hydroxide (LDH) precursor. The successive ionic layer adsorption and reaction (SILAR) method is applied to deposit CdS quantum dots. The effects of sensitizing cycles on the performance of CdS QDSSC are studied. Scanning electron microscopy (SEM), Transmission electron microscope (TEM) and X-ray diffraction (XRD) are used to identify the surface profile and crystal structure of the mixed metal oxides anode. The photovoltaic performance of the QDSSC is studied by the electrochemical method. The new CdS QDSSC exhibits power conversion efficiency (PCE) up to 0.48% when the anode was sensitized for eight cycles. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Reliability assessment of aging structures subjected to gradual and shock deteriorations

    International Nuclear Information System (INIS)

    Wang, Cao; Zhang, Hao; Li, Quanwang

    2017-01-01

    Civil structures and infrastructure facilities are susceptible to deterioration posed by the effects of natural hazards and aggressive environmental conditions. These factors may increase the risk of service interruption of infrastructures, and should be taken into account when assessing the structural reliability during an infrastructure's service life. Modeling the resistance deterioration process reasonably is the basis for structural reliability analysis. In this paper, a novel model is developed for describing the deterioration of aging structures. The deterioration is a combination of two stochastic processes: the gradual deterioration posed by environmental effects and the shock deterioration caused by severe load attacks. The dependency of the deterioration magnitude on the load intensity is considered. The Gaussian copula function is employed to help construct the joint distribution of correlated random variables. Semi-analytical methods are developed to assess the structural failure time and the number of significant load events (shocks) to failure. Illustrative examples are presented to demonstrate the applicability of the proposed model in structural reliability analysis. Parametric studies are performed to investigate the role of deterioration-load correlation in structural reliability. - Highlights: • A new resistance deterioration model for aging structures is proposed. • Time-dependent reliability analysis methods incorporating the proposed deterioration model are developed. • Parametric studies are performed to investigate the role of deterioration-load correlation in structural reliability.

  1. Electrical Properties of Electrospun Sb-Doped Tin Oxide Nanofibers

    International Nuclear Information System (INIS)

    Leon-Brito, Neliza; Melendez, Anamaris; Ramos, Idalia; Pinto, Nicholas J; Santiago-Aviles, Jorge J

    2007-01-01

    Transparent and conducting tin oxide fibers are of considerable interest for solar energy conversion, sensors and in various electrode applications. Appropriate doping can further enhance the conductivity of the fibers without loosing optical transparency. Undoped and antimony-doped tin oxide fibers have been synthesized by our group in previous work using electrospinning and metallorganic decomposition techniques. The undoped tin oxide fibers were obtained using a mixture of pure tin oxide sol made from tin (IV) chloride : water : propanol : isopropanol at a molar ratio of 1:9:9:6, and a viscous solution made from poly(ethylene oxide) (PEO) and chloroform at a ratio of 200 mg PEO/10 mL chloroform. In this work, antimony doped fibers were obtained by adding a dopant solution of antimony trichloride and isopropanol at a ratio of 2.2812 g antimony trichloride/10 ml isopropanol to the original tin oxide precursor solution. The Sb concentration in the precursor solution is 1.5%. After deposition, the fibers were sintered 600deg. C in air for two hours. The electrical conductivity of single fibers measured at room temperature increases by up to three orders of magnitude when compared to undoped fibers prepared using the same method. The resistivity change as a function of the annealing temperature can be attributed to the thermally activated formation of a nearly stoichoimetric solid. The resistivity of the fibers changes monotonically with temperature from 714Ω-cm at 2 K to 0.1Ω-cm at 300 K. In the temperature range from 2 to 8 K the fibers have a positive magnetoresistance (MR) with the highest value of 155 % at 2 K and ±9 T. At temperatures of 10 and 12 K the sign of MR changes to negative values for low magnetic fields and positive for high magnetic fields. For higher temperatures (15 K and above) the MR becomes negative and its magnitude decreases with temperature

  2. Combined TiN- and TaN temperature compensated thin film resistors

    International Nuclear Information System (INIS)

    Malmros, Anna; Andersson, Kristoffer; Rorsman, Niklas

    2012-01-01

    The opposite signs of the temperature coefficient of resistance (TCR) of two thin film materials, titanium nitride (TiN) and tantalum nitride (TaN), were used to form temperature compensated thin film resistors (TFRs). The principle of designing temperature compensated TFRs by connecting TFRs of each compound in series or in parallel was demonstrated. TiN, TaN, and combined TiN and TaN TFRs for monolithic microwave integrated circuits (MMICs) were fabricated by reactive sputtering. DC characterization was performed over the temperature range of 30–200 °C. The TiN TFRs exhibited an increase in resistivity with temperature with TCRs of 540 and 750 ppm/°C. The TaN TFR on the other hand exhibited a negative TCR of − 470 ppm/°C. The shunted TFRs were fabricated by serial deposition of TiN and TaN to form a bilayer component. The TCRs of the series- and shunt configurations were experimentally reduced to − 60 and 100 ppm/°C, respectively. The concept of temperature compensation was used to build a Wheatstone bridge with an application in on-chip temperature sensing.

  3. Synthesis, Spectral Characterization and Antioxidant Activity of Tin(II-Morin Complex

    Directory of Open Access Journals (Sweden)

    Shahabuddin Memon

    2012-12-01

    Full Text Available The study focuses on the interaction between morin and Tin(II and the resulting complex was characterized through various analytical techniques by comparing it with morin. The complexation was confirmed at first by UV-Vis study, which shows that addition of Tin(II to morin may produce bathochromic shifts indicative of complex formation. IR spectral studies indicated that carbonyl has involved in coordination with Tin(II. Moreover, 1H-NMR studies validated that in conjunction with carbonyl, 3-OH of morin is more appropriate to be involved in complexation by replacement of its proton. Scavenging activities of morin and its Tin(II complex on DPPH• radical showed the inhibitory rates of 65% and 49%, respectively. In addition, the reducing capacity of morin was outstanding at 0.5 and 2.0 mg/ml concentrations relative to Tin(II complex. Overall, the study potentially shows the strong impact in order to design the anticancer drugs jointly from its cytotoxic potential and antioxidant activities, thereby selectively targeting the cancerous cells in result increasing their therapeutic index as well as extra advantages over other anticancer drugs.

  4. Reactivation of the Shock-Tunnel Facility at Fort Cronkhite. Final report

    International Nuclear Information System (INIS)

    1982-05-01

    This final report describes the results of work undertaken to reactivate the Shock Tunnel Facility at Battery Townsley, Fort Cronkhite, Marin County, California. The facility has been reactivated and can not be utilized for blast testing. The major emphasis will be testing of concepts pertaining to programs of interest to the Federal Emergency Management Agency (FEMA) and in particular to civil defense oriented research. However, a wide variety of testing requirements can be accommodated. For example, past programs at the facility have included: tests of debris from trees subjected to blast for Bell Telephone Laboratories; tests of the response of aluminum hull panels to blast loading and of the response of a model surface effects ship for the Naval Ship Research and Development center, and tests of the response of a radome prototype to blast loading conducted for ANCOM (the radome manufacturer). The Shock Tunnel Facility is located in a former coastal defense 16-inch gun emplacement constructed by the US Army beginning in 1938. It was converted in 1967 to serve as a facility for full-scale testing of the loading and response of structural elements and civil defense equipment. It remained in operation until November 1976 when Battery Townsley was turned over to the National Park Service. Work under the present purchase order consisted of the following major tasks: (I) cleanup and secure the facility, (II) reactivate the shock tunnel, and (III) design permanent facility improvements

  5. Boundary element analysis of stress due to thermal shock loading or reactor pressure vessel nozzle; Napetostna analiza pri nestacionarni termicni obremenitvi cevnega prikljucka reaktorske tlacne posode z metodo robnih elementov

    Energy Technology Data Exchange (ETDEWEB)

    Kramberger, J; Potrc, I [Tehniska fakulteta, Maribor (Yugoslavia)

    1989-07-01

    Apart from being exposed to the primary loading of internal pressure and steady temperature field, the reactor pressure vessel is also subject to various thermal transients (thermal shocks). Theoretical and experimental stress analyses show that severe material stresses occur in the nozzle area of the pressure vessel which may lead to defects (cracks). It has been our aim to evaluate these stresses by the use of the Boundary Element method. (author)

  6. Impulsive shock induced single drop steam explosion visualized by high-speed x-ray radiography and photography - metallic melt

    International Nuclear Information System (INIS)

    Park, H. S.; Hansson, R. C.; Sehgal, B. R.

    2003-01-01

    Experimental investigation of fine fragmentation process during vapor explosion was conducted in a small-scale single drop system employing continuous high-speed X-ray radiography and photography. A molten tin drop of about 0.7 g at approximately 1000 .deg. C was dropped into a water pool, at temperatures ranging from 20 to 90 .deg. C, and the explosion was triggered by an external shock pulse of about 1 MPa. X-ray radiographs show that finely fragmented melt particles accelerates to the vapor bubble boundary and forms a particle shell during the period of vapor bubble expansion due to vapor explosions. From the photographs, it was possible to observe a number of counter-jets on the vapor boundary. For tests with highly subcooled coolant, local explosion due to external impulsive shock trigger initiates the stratified mode of explosion along the entire melt surface. For tests with lower subcooled coolant local explosions were initiated by an external impulsive shock trigger and by collapse of vapor/gas pocket attached on the top of the melt drop. Transient spatial distribution map of melt fragments during vapor explosion was obtained by a series of image processing and calibration tests

  7. Thermal shock resistance of thick boron-doped diamond under extreme heat loads

    NARCIS (Netherlands)

    De Temmerman, G.; Dodson, J.; Linke, J.; Lisgo, S.; Pintsuk, G.; Porro, S.; Scarsbrook, G.

    2011-01-01

    Thick free-standing boron-doped diamonds were prepared by microwave plasma assisted chemical vapour deposition. Samples with a final thickness close to 5 mm and with lateral dimensions 25 x 25 mm were produced. The thermal shock resistance of the material was tested by exposure in the JUDITH

  8. Colorimetric visualization of tin corrosion: A method for early stage corrosion detection on printed circuit boards

    DEFF Research Database (Denmark)

    Verdingovas, Vadimas; Jellesen, Morten Stendahl; Ambat, Rajan

    2017-01-01

    A majority of printed circuit board surfaces are covered with tin, therefore tin corrosion under humid conditions and movement of tin ions under the influence of an electric field plays an important role in the corrosion failure development. Tracking tin corrosion products spread on the printed c...

  9. Shock wave effects in copper: Design of an experimental device for post recovery mechanical testing

    International Nuclear Information System (INIS)

    Buy, Francois; Llorca, Fabrice

    2002-01-01

    The mechanical behavior of metals may prove high changes with strain rate and pressure loading history. In order to investigate the effect of a shock on the ulterior mechanical behavior of high purity copper, we set up an experimental device inspired from G. T. Gray III's works. This device, based on the trapping of shock waves after a plane plate impact is validated by numerical simulations. The aim of these simulations is the evaluation of the heterogeneity of plastic deformation. Shock pressures up to 10 GPa have been investigated. The plastic strain levels subsequent to the shock are between 0.08 and 0.15 in the sample

  10. The tin mining and heavy mineral processing industry in the Kinta Valley, Perak, Malaysia

    International Nuclear Information System (INIS)

    Lee Swee Ching

    1994-01-01

    Overview of the tin mining and heavy mineral processing in the Kinta Valley, Perak, Malaysia was presented. Amang, a mixture composed of tin ore, sand, ilmenite, monazite, zircon, xenotime, struvite, etc , as a product from tin mining activities was discussed too in this paper

  11. Electrospun polyacrylonitrile nanofibers loaded with silver nanoparticles by silver mirror reaction

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yongzheng; Li, Yajing; Zhang, Jianfeng; Yu, Zhongzhen; Yang, Dongzhi, E-mail: yangdz@mail.buct.edu.cn

    2015-06-01

    The silver mirror reaction (SMR) method was selected in this paper to modify electrospun polyacrylonitrile (PAN) nanofibers, and these nanofibers loaded with silver nanoparticles showed excellent antibacterial properties. PAN nanofibers were first pretreated in AgNO{sub 3} aqueous solution before the SMR process so that the silver nanoparticles were distributed evenly on the outer surface of the nanofibers. The final PAN nanofibers were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), TEM-selected area electron diffraction (SAED), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). SEM, TEM micrographs and SAED patterns confirmed homogeneous dispersion of the silver nanoparticles which were composed of monocrystals with diameters 20–30 nm. EDS and XRD results showed that these monocrystals tended to form face-centered cubic single silver. TGA test indicated that the nanoparticles loaded on the nanofibers reached above 50 wt.%. This material was also evaluated by the viable cell-counting method. The results indicated that PAN nanofibers loaded with silver nanoparticles exhibited excellent antimicrobial activities against gram-negative Escherichia coli (E. coli), gram-positive Staphylococcus aureus (S. aureus) and the fungus Monilia albicans. Thus, this material had many potential applications in biomedical fields. - Highlights: • Silver mirror reaction was used to prepare nanofibers loaded with silver nanoparticles. • The SAED patterns demonstrated the monocrystallinity of silver nanocrystals. • The XRD results showed nanoparticles tended to be face-centered cubic single silver. • The material showed excellent antimicrobial activities against bacteria and fungi.

  12. Heat Shock Proteins in Tendinopathy: Novel Molecular Regulators

    Directory of Open Access Journals (Sweden)

    Neal L. Millar

    2012-01-01

    Full Text Available Tendon disorders—tendinopathies—are the primary reason for musculoskeletal consultation in primary care and account for up to 30% of rheumatological consultations. Whilst the molecular pathophysiology of tendinopathy remains difficult to interpret the disease process involving repetitive stress, and cellular load provides important mechanistic insight into the area of heat shock proteins which spans many disease processes in the autoimmune community. Heat shock proteins, also called damage-associated molecular patterns (DAMPs, are rapidly released following nonprogrammed cell death, are key effectors of the innate immune system, and critically restore homeostasis by promoting the reconstruction of the effected tissue. Our investigations have highlighted a key role for HSPs in tendion disease which may ultimately affect tissue rescue mechanisms in tendon pathology. This paper aims to provide an overview of the biology of heat shock proteins in soft tissue and how these mediators may be important regulators of inflammatory mediators and matrix regulation in tendinopathy.

  13. Determination of Size Distributions in Nanocrystalline Powders by TEM, XRD and SAXS

    DEFF Research Database (Denmark)

    Jensen, Henrik; Pedersen, Jørgen Houe; Jørgensen, Jens Erik

    2006-01-01

    Crystallite size distributions and particle size distributions were determined by TEM, XRD, and SAXS for three commercially available TiO2 samples and one homemade. The theoretical Guinier Model was fitted to the experimental data and compared to analytical expressions. Modeling of the XRD spectra...... the size distribution obtained from the XRD experiments; however, a good agreement was obtained between the two techniques. Electron microscopy, SEM and TEM, confirmed the primary particle sizes, the size distributions, and the shapes obtained by XRD and SAXS. The SSEC78 powder and the commercially...

  14. Design basis for resistance to shock and vibration

    International Nuclear Information System (INIS)

    Glass, R.E.; Gwinn, K.W.

    1989-01-01

    Sandia National Laboratories, in conjunction with its participation in the American National Standards Institute (ANSI) writing groups, has undertaken to provide an experimental and analytical basis for the design of components of radioactive materials packages to resist normal transport shock and vibration loads. Previous efforts have resulted in an overly conservative shock spectra description of the loads in the tie-downs and cask attachment points anticipated during normal shipment. The present effort is aimed at predicting the actual loads so that the design basis can be accurately determined. This goal is being accomplished with road simulator and over-the-road tests and the development of an analytical model. This model is used to parametrically evaluate and envelop the transportation systems' responses. The parameters to be varied include damping, stiffness, geometry, and cargo mass. The over-the-road tests provide operational data that are used to validate the selection of environments for the road simulator tests. The road simulator tests provide verification for the model. This verification is accomplished since the road simulator tests provide not only the system response which can be measured in over-the-road tests but also the system input. Finally, when the model has been verified, it can be used to vary parameters to envelop a wide range of normal transport conditions

  15. Design basis for resistance to shock and vibration

    International Nuclear Information System (INIS)

    Glass, R.E.; Gwinn, K.W.

    1989-01-01

    Sandia National Laboratories, in conjunction with its participation in the American National Standards Institute (ANSI) writing groups, has undertaken to provide an experimental and analytical basis for the design of components of radioactive materials packages to resist normal transport shock and vibration loads. Previous efforts have resulted in an overly conservative shock spectra description of the loads in the tie-downs and cask attachment points anticipated during normal shipment. The present effort is aimed at predicting the actual loads so that the design basis can be accurately determined. This goal is being accomplished with road simulator and over-the-road tests and the development of an analytical model. This model is used to parametrically evaluate and envelop the transportation systems responses. The parameters to be varied include damping, stiffness, geometry, and cargo mass. The over-the-road tests provide operational data that are used to validate the selection of environments for the road simulator tests. The road simulator tests provide verification for the model. This verification is accomplished since the road simulator tests provide not only the system response which can be measured in over-the-road tests but also the system input. Finally, when the model has been verified, it can be used to vary parameters to envelope a wide range of normal transport conditions

  16. Rapid synthesis of tin oxide nanostructures by microwave-assisted thermal oxidation for sensor applications

    Science.gov (United States)

    Phadungdhitidhada, S.; Ruankham, P.; Gardchareon, A.; Wongratanaphisan, D.; Choopun, S.

    2017-09-01

    In the present work nanostructures of tin oxides were synthesized by a microwave-assisted thermal oxidation. Tin precursor powder was loaded into a cylindrical quartz tube and further radiated in a microwave oven. The as-synthesized products were characterized by scanning electron microscope, transmission electron microscope, and x-ray diffractometer. The results showed that two different morphologies of SnO2 microwires (MWs) and nanoparticles (NPs) were obtained in one minute of microwave radiation under atmospheric ambient. A few tens of the SnO2 MWs with the length of 10-50 µm were found. Some parts of the MWs were decorated with the SnO2 NPs. However, most of the products were SnO2 NPs with the diameter ranging from 30-200 nm. Preparation under loosely closed system lead to mixed phase SnO-SnO2 NPs with diameter of 30-200 nm. The single-phase of SnO2 could be obtained by mixing the Sn precursor powders with CuO2. The products were mostly found to be SnO2 nanowires (NWs) and MWs. The diameter of SnO2 NWs was less than 50 nm. The SnO2 NPs, MWs, and NWs were in the cassiterite rutile structure phase. The SnO NPs was in the tetragonal structure phase. The growth direction of the SnO2 NWs was observed in (1 1 0) and (2 2 1) direction. The ethanol sensor performance of these tin oxide nanostructures showed that the SnO-SnO2 NPs exhibited extremely high sensitivity. Invited talk at 5th Thailand International Nanotechnology Conference (Nano Thailand-2016), 27-29 November 2016, Nakhon Ratchasima, Thailand.

  17. 77 FR 34938 - Certain Tin Mill Products From Japan: Continuation of Antidumping Duty Order

    Science.gov (United States)

    2012-06-12

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-588-854] Certain Tin Mill Products... duty order on certain tin mill products from Japan would likely lead to continuation or recurrence of...: Background On August 28, 2000, the Department published the antidumping duty order on certain tin mill...

  18. Improving the performance of fluorine-doped tin oxide by adding salt

    Energy Technology Data Exchange (ETDEWEB)

    Purwanto, Agus, E-mail: Aguspur@uns.ac.id [Department of Chemical Engineering, Faculty of Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A, Surakarta, Central Java 57126 (Indonesia); Widiyandari, Hendri [Department of Physics, Faculty of Sciences and Mathematics, Diponegoro University, Jl. Prof. Dr. Soedarto, Tembalang, Semarang 50275 (Indonesia); Suryana, Risa [Department of Physics, Faculty of Mathematics and Natural Sciences, Sebelas Maret University, Jl. Ir. Sutami 36 A, Surakarta, Central Java 57126 (Indonesia); Jumari, Arif [Department of Chemical Engineering, Faculty of Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A, Surakarta, Central Java 57126 (Indonesia)

    2015-07-01

    High-performance fluorine-doped tin oxide (FTO) films were fabricated via a spray deposition technique with salt added to the precursor. The addition of NaCl in the precursor improved the conductivity of the FTO films. Increasing the NaCl concentration to its optimal concentration reduced the sheet resistance of the FTO film. The optimal values for the addition of a NaCl were 0.5, 0.5, 1.5, and 1.5 at.% for the FTO film prepared using NH{sub 4}F concentration of 4, 10, 16, and 22 at.%, respectively. The lowest sheet resistance of the salt-added FTO film was 4.8 Ω/□. The FTO film averaged a transmittance of more than 80% in the visible range region (λ = 400–800 nm). XRD diffractograms confirmed that the crystal structure of the as-grown FTO film was that of a tetragonal SnO{sub 2} and that the addition of salt improved its crystallinity. This film has the potential for use as an electrode for dye-sensitized solar cells (DSSCs). - Highlights: • A method to improve FTO performance using the addition of salt • The FTO film exhibited high performance of conductivity and light transmittance. • This technique is low-cost, fast and scales-up easily using simple devices.

  19. State of the Art Power-in Tube Niobium-Tin Superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Godeke, A.; Ouden, A. Den; Nijhuis, A.; ten Kate, H.H.J.

    2008-06-01

    Powder-in-Tube (PIT) processed Niobium-Tin wires are commercially manufactured for nearly three decades and have demonstrated a combination of very high current density (presently up to 2500 A mm{sup -2} non-Cu at 12 T and 4.2 K) with fine (35 {micro}m), well separated filaments. We review the developments that have led to the present state of the art PIT Niobium-Tin wires, discuss the wire manufacturing and A15 formation processes, and describe typical superconducting performance in relation to magnetic field and strain. We further highlight successful applications of PIT wires and conclude with an outlook on possibilities for further improvements in the performance of PIT Niobium-Tin wires.

  20. Novel Sample-handling Approach for XRD Analysis with Minimal Sample Preparation

    Science.gov (United States)

    Sarrazin, P.; Chipera, S.; Bish, D.; Blake, D.; Feldman, S.; Vaniman, D.; Bryson, C.

    2004-01-01

    Sample preparation and sample handling are among the most critical operations associated with X-ray diffraction (XRD) analysis. These operations require attention in a laboratory environment, but they become a major constraint in the deployment of XRD instruments for robotic planetary exploration. We are developing a novel sample handling system that dramatically relaxes the constraints on sample preparation by allowing characterization of coarse-grained material that would normally be impossible to analyze with conventional powder-XRD techniques.

  1. Interesterification of rapeseed oil catalyzed by tin octoate

    International Nuclear Information System (INIS)

    Galia, Alessandro; Centineo, Alessio; Saracco, Guido; Schiavo, Benedetto; Scialdone, Onofrio

    2014-01-01

    The interesterification of rapeseed oil was performed for the first time by using tin octoate as Lewis acid homogeneous catalysts and methyl or ethyl acetate as acyl acceptors in a batch reactor, within the temperature range 393–483 K. The yields in fatty acid ethyl esters (FAEE) and triacetin (TA) after 20 h of reaction time increased from 8% and 2%–to 61% and 22%, respectively, when the reaction temperature increased from 423 to 483 K. An optimum value of 40 for the acyl acceptor to oil molar ratio was found to be necessary to match good fatty acid alkyl ester yields with high enough reaction rate. The rate of generation of esters was significantly higher when methyl acetate was used as acyl acceptor instead of its ethyl homologue. The collected results suggest that tin octoate can be used as effective catalyst for the interesterification of rapeseed oil with methyl or ethyl acetate being highly soluble in the reaction system, less expensive than enzymes and allowing the operator to work under milder conditions than supercritical interesterification processes. - Highlights: • We study the interesterification of rapeseed oil catalyzed by tin(II) octoate. • Tin(II) octoate is an effective homogeneous catalyst at 483 K. • The acyl acceptor to oil molar ratio must be optimized. • Higher rate of reaction is obtained with methyl acetate as acyl acceptor

  2. Highly conducting and transparent sprayed indium tin oxide

    Energy Technology Data Exchange (ETDEWEB)

    Rami, M.; Benamar, E.; Messaoudi, C.; Sayah, D.; Ennaoui, A. (Faculte des Sciences, Rabat (Morocco). Lab. de Physique des Materiaux)

    1998-03-01

    Indium tin oxide (ITO) has a wide range of applications in solar cells (e.g. by controlling the resistivity, we can use low conductivity ITO as buffer layer and highly conducting ITO as front contact in thin films CuInS[sub 2] and CuInSe[sub 2] based solar cells) due to its wide band gap (sufficient to be transparent) in both visible and near infrared range, and high carrier concentrations with metallic conduction. A variety of deposition techniques such as reactive electron beam evaporation, DC magnetron sputtering, evaporation, reactive thermal deposition, and spray pyrolysis have been used for the preparation of undoped and tin doped indium oxide. This latter process which makes possible the preparation of large area coatings has attracted considerable attention due to its simplicity and large scale with low cost fabrication. It has been used here to deposit highly transparent and conducting films of tin doped indium oxide onto glass substrates. The electrical, optical and structural properties have been investigated as a function of various deposition parameters namely dopant concentrations, temperature and nature of substrates. X-ray diffraction patterns have shown that deposited films are polycrystalline without second phases and have preferred orientation [400]. INdium tin oxide layers with small resistivity value around 7.10[sup -5] [omega].cm and transmission coefficient in the visible and near IR range of about 85-90% have been easily obtained. (authors) 13 refs.

  3. Analysis of synthetic profile of CZTS as photovoltaic material obtained with variations of titanium and TiN

    Science.gov (United States)

    Muñoz, M.; Vera, E.; Gómez, J.; Pineda, Y.

    2017-12-01

    Semiconductor type Cu2ZnTiS4 (CZTiS) and Cu2ZnSnS4 (CZTS),were synthetized starting from a hydrothermal route from precursor powders such as copper, zinc, tin, titanium isopropoxide and tiocarbammide metal nitrates dissolved in deionized water in concentrations of 1molL-1. Dosed and placed in a steel autoclave equipped with a Teflon jacket under magnetic stirring (150rpm) and at a temperature of 300°C for 24 hours in order to promote the formation of the respective ceramic phases. Segregates have been repeatedly washed with ethanol at all times until obtaining crystalline-looking solids. Subsequently, in order to promote the production of pure crystalline phases, the materials were subjected to a second reaction stage in a tubular furnace at 400°C in flow (50mLmin-1) for the purpose of Reduce the concentration of secondary phases of sulphides. The characterization of the CZTiS and CZTS materials was performed by X-ray Diffraction (XRD) and Raman spectroscopy where the presence of Kesterite type crystalline structures was confirmed in the two materials revealing that the effect of titanium with a higher ionic radius than tin produces a distortion in the cell of the CZTiS material compared to the report for the CZTS system. The results of Scanning Electron Microscopy (SEM), confirm the regular aggregates obtained with composition consistent with the proposal theoretically and validated by Energy-Dispersion X-ray Spectroscopy (EDX) techniques and comparison between secondary emission spectra and Retro-dispersed.

  4. Characterization of surface-modified LiMn2O4 cathode materials with indium tin oxide (ITO) coatings and their electrochemical performance

    International Nuclear Information System (INIS)

    Kim, Chang-Sam; Kwon, Soon-Ho; Yoon, Jong-Won

    2014-01-01

    Graphical abstract: -- Highlights: • Indium tin oxide (ITO) is used to modify the surface of LiMn 2 O 4 by a sol–gel method. • The surface-modified layer was observed at a scale of several nanometers on LiMn 2 O 4 . • The ITO-coated LiMn 2 O 4 shows better capacity retention at 30 and 55 °C than pristine LiMn 2 O 4 . -- Abstract: Indium tin oxide (ITO) is used to modify the surface of LiMn 2 O 4 by a sol–gel method in an attempt to improve its electrochemical performance at elevated temperatures. The surface-modified LiMn 2 O 4 is characterized via XRD, FE-SEM, TEM, Auger electron spectroscopy (AES) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The surface layer modified by substitution with indium was observed at a scale of several nanometers near the surface on LiMn 2 O 4 . The concentration of ITO for electrochemical performance was varied from 0.3 wt% to 0.8 wt%. The 0.5 wt% ITO coated LiMn 2 O 4 showed the best electrochemical performance. This enhancement in electrochemical performance is mainly attributed to the effect of the surface layer modified through ITO, which could suppress Mn dissolution and reduce the charge transfer resistance at the solid electrolyte interface

  5. Temperatures, strains and crack behavior during local thermal shock tests on the RPV-cylinder of the HDR

    International Nuclear Information System (INIS)

    Neubrech, G.E.; Goerner, F.; Siebler, T.

    1987-01-01

    This report summarises and critically discusses the results obtained from thermal shocks locally applied to the inner surface of the RPV-cylinder. This evaluation is based on on-line measurements (temperatures and strains at the RPV-wall during the thermal shock loading, non-destructive-testing), on materials investigations, and on theoretical investigations (finite element calculations, fracture mechanics analyses). The comparison between the corresponding measured and calculated results serves as a basis for subsequent assessments. It was the object of these tests to achieve the following primary aims: - Investigation of the loading conditions produced by local thermal shocks during realistic cooling processes. - A better understanding of the physical processes involved in crack initiation and propagation resulting from thermocyclic loading. - Assessment of non-destructive-testing methods with respect to detection and analysis of cracks as a basis for fracture mechanical evaluations. - Assessment of the reliability of the applied structural analysis methods. - Production of naturally formed deep cracks on the inner surface of the RPV-cylinder by means of excessive cooling processes. (orig./HP)

  6. XPS investigations of tribolayers formed on TiN and (Ti,Re)N coatings

    Energy Technology Data Exchange (ETDEWEB)

    Oktay, Serkan; Kahraman, Zafer; Urgen, Mustafa; Kazmanli, Kursat, E-mail: kursat@itu.edu.tr

    2015-02-15

    Graphical abstract: - Highlights: • The (Ti,Re)N coating (8 ± 1.9 at.% Re) consisted of TiN and ReNx (x > 1.33) phases. • TiO{sub 2} provided low friction coefficient to TiN coating at 150 °C. • Re addition to TiN drastically dropped the friction coefficients to 0.17–0.22. • Re{sub 2}O{sub 7} provided very low friction coefficient to (Ti,Re)N coating. • Re addition to TiN improved the wear behavior. - Abstract: TiN and (Ti,Re)N coatings were deposited on high-speed-steel substrates by a hybrid coating system composed of cathodic arc PVD and magnetron sputtering techniques. In order to keep rhenium content low (8 ± 1.9 at.%) in the coating, magnetron sputtering technique was utilized to evaporate rhenium. The (Ti,Re)N coating consisted of TiN and ReN{sub x} (x > 1.33) phases. The hardness of TiN and (Ti,Re)N were 31 GPa and 29 GPa ( ± 2 GPa), respectively. Tribological behaviors of the samples were tested against Al{sub 2}O{sub 3} balls at 21 °C (RT) and 150 °C (HT) by reciprocating wear technique. The tribolayers were analyzed by XPS technique. Friction coefficients of TiN were 0.56, 0.35 for 21 °C and 150 °C tests, respectively. Rhenium addition to TiN drastically dropped the friction coefficients to 0.22 and 0.17 for RT and HT samples. Rhenium addition also improved the wear resistance of the coating at both test temperatures. For TiN, main oxide component of the tribolayers was Ti{sub 2}O{sub 3} for RT tests and TiO{sub 2} for HT tests. The oxide layer formed on (Ti,Re)N were the mixture of TiO{sub 2}, Ti−O−N, ReO{sub 2} and Re{sub 2}O{sub 7} for both test temperatures. Re{sub 2}O{sub 7} provided very low friction coefficient to (Ti,Re)N. The findings are consistent with the crystal chemistry approach.

  7. Reversible storage of lithium in a rambutan-like tin-carbon electrode.

    Science.gov (United States)

    Deng, Da; Lee, Jim Yang

    2009-01-01

    Fruity electrodes: A simple bottom-up self-assembly method was used to fabricate rambutan-like tin-carbon (Sn@C) nanoarchitecture (see scheme, green Sn) to improve the reversible storage of lithium in tin. The mechanism of the growth of the pear-like hairs is explored.

  8. Studies in group IV organometallic chemistry XXX. Synthesis of compounds containing tin---titanium and tin---zirconium bonds

    NARCIS (Netherlands)

    Creemers, H.M.J.C.; Verbeek, F.; Noltes, J.G.

    1968-01-01

    Starting from the tetrakis(diethylamino) derivatives of titanium and zirconium and pheyltin hydrides six intermetalic compounds contianing up to nine tin and titanium(or zirconium) atoms have been obtained by hydrostannolysis type reactions.

  9. Time-history of shock waves overrunning three-dimensional, cylindrical models

    International Nuclear Information System (INIS)

    Langheim, H.; Loeffler, E.

    To investigate the time-history of the Mach-stem of a shock wave overrunning a nuclear power plant shadowgraphs of threedimensional, cylindrical models with a globe cap were analysed. These models simulating the containment building differ only in the height of the cylinder. They were exposed with shock waves of shock strengths of 1.2 and 1.4, being equal to a peak reflexion overpressure of 0.45 resp. 1.0 bar. The time-histories of the Mach-stem differ only slightly. For this reason it can be stated that these time-histories are independent of the shock strength and the height of the cylinder in the prescribed range of the research program. In comparison with values given in the literature great differences were found at the rear side near the stagnation point of the globe cap resp. the stagnation line of the cylinder. The measured time for overrunning of the shock wave is the same as the time of arrival of the pressure-pulse at the interesting point of the model. This knowledge is a necessary premise for pressure-measurings from which the total load of structure can be determined. (orig.) [de

  10. Effect of pulsed voltage on electrochemical migration of tin in electronics

    DEFF Research Database (Denmark)

    Verdingovas, Vadimas; Jellesen, Morten Stendahl; Ambat, Rajan

    2015-01-01

    formation and increases the charge transferred between the electrodes over time. With increase of duty cycle, increases the anodic dissolution of tin, which was visualized using a tin ion indicator applied on the components prior to applying the voltage. The anodic dissolution of tin significantly...... respectively at 10 and 5 V, while the duty cycle and the pulse width were varied in the range of ms. The results showed that varying of pulse width at fixed duty cycle has a minor effect under investigated conditions, whereas increasing duty cycle significantly reduces the time to short due to dendrite...

  11. Hydrothermal synthesis of tungsten doped tin dioxide nanocrystals

    Science.gov (United States)

    Zhou, Cailong; Li, Yufeng; Chen, Yiwen; Lin, Jing

    2018-01-01

    Tungsten doped tin dioxide (WTO) nanocrystals were synthesized through a one-step hydrothermal method. The structure, composition and morphology of WTO nanocrystals were characterized by x-ray diffraction, x-ray photoelectron spectroscopy, energy dispersive x-ray spectroscopy, UV-vis diffuse reflectance spectra, zeta potential analysis and high-resolution transmission electron microscopy. Results show that the as-prepared WTO nanocrystals were rutile-type structure with the size near 13 nm. Compared with the undoped tin dioxide nanocrystals, the WTO nanocrystals possessed better dispersity in ethanol phase and formed transparent sol.

  12. Thermal interaction for molten tin dropped into water

    Energy Technology Data Exchange (ETDEWEB)

    Arakeri, V.H.; Catton, I.; Kastenberg, W.E.; Plesset, M.S.

    1978-03-01

    Multiflash photography with extremely short duration exposure times per flash was used to observe the interaction of molten tin dropped into a water bath. Detailed photographic evidence is presented which demonstrates that transition, or nucleate boiling, is a possible triggering mechanism for vapor explosions. It was also found that the thermal constraints required to produce vapor explosions could be relaxed by introducing a stable thermal stratification within the coolant. In the present work, the threshold value of the initial tin temperature required for vapor explosion was reduced from about 500 to 343/sup 0/C.

  13. Preparation, characterization and applications of novel carbon and nitrogen codoped TiO2 nanoparticles from annealing TiN under CO atmosphere

    International Nuclear Information System (INIS)

    Sun, Mingxuan; Song, Peng; Li, Jing; Cui, Xiaoli

    2013-01-01

    Graphical abstract: Carbon and nitrogen codoped TiO 2 nanoparticles were firstly fabricated by calcining TiN powder under CO atmosphere at different temperatures between 400 and 600 °C, both the improved photocatalytic activity for degradation of methylene blue and enhanced photovoltaic performance for dye sensitized solar cells were demonstrated. - Highlights: • CN-codoped TiO 2 nanoparticles were prepared by calcining TiN under CO atmosphere. • More visible light response was confirmed by UV–vis DRS and photocatalytic results. • Enhanced conversion efficiency was observed for the DSSCs from CN-TiO 2 photoanode. • CN-codoping played an important role to improve the photocatalytic performance. - Abstract: Carbon and nitrogen codoped titania (CN-TiO 2 ) nanoparticles were fabricated by calcining titanium nitride (TiN) nanoparticles under carbon monoxide (CO) atmosphere at four different temperatures in a range of 400–600 °C. The as-prepared samples were characterized with X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). Enhanced light absorption in both the UV and visible light region was observed for the resulted CN-TiO 2 nanoparticles in ultraviolet-visible diffuse reflectance spectroscopy (UV–vis DRS). Improved photocatalytic activity toward the degradation of methylene blue by the CN-TiO 2 nanoparticles was demonstrated under UV and visible light, respectively. The highest degradation rate was achieved for CN-TiO 2 nanoparticles (13%) compared to N-TiO 2 (10%) and the commercial P25 (5%) under visible light illumination for 40 min. Furthermore, the improved photocatalytic activity of CN-TiO 2 was also confirmed by the degradation of colorless resorcinol under UV–vis light irradiation. Dye-sensitized solar cells (DSSCs) were fabricated using P25, N-TiO 2 and CN-TiO 2 photoanodes, respectively. The highest conversion efficiency of 3.31% was achieved by the DSSCs based on the

  14. The effect of shock-wave strain on the acoustic and elastic properties of titanium nickelide upon phase transitions

    International Nuclear Information System (INIS)

    Popov, N.N.; Panchenko, A.M.; Sevryugina, I.V.; Novikov, S.A.

    2002-01-01

    The data are obtained for the influence of preliminary plastic deformation of titanium nickelide in an austenitic state on the character of its elastic properties variation during various type phase transitions. It is shown that the defect structure evolution occurring as a result of shock wave loading has a combined ambiguous effect on microstructural mechanisms being the basis for martensitic phase transformations. Shock wave loading is stated to stimulate the dislocation-displacement mechanism of R-phase formation and to increase the stability of R-phase to R→B19'-transition [ru

  15. High Strain Rate Deformation Mechanisms of Body Centered Cubic Material Subjected to Impact Loading

    Science.gov (United States)

    Visser, William

    Low carbon steel is the most common grade of structural steel used; it has carbon content of 0.05% to 0.25% and very low content of alloying elements. It is produced in great quantities and provides material properties that are acceptable for many engineering applications, particularly in the construction industry in which low carbon steel is widely used as the strengthening phase in civil structures. The overall goal of this dissertation was to investigate the deformation response of A572 grade 50 steel when subjected to impact loading. This steel has a 0.23% by weight carbon content and has less than 2% additional alloying elements. The deformation mechanisms of this steel under shock loading conditions include both dislocation motion and twin formation. The goal of this work was achieved by performing experimental, analytical and numerical research in three integrated tasks. The first is to determine the relationship between the evolution of deformation twins and the impact pressure. Secondly, a stress criterion for twin nucleation during high strain rate loading was developed which can account for the strain history or initial dislocation density. Lastly, a method was applied for separating the effects of dislocations and twins generated by shock loading in order to determine their role in controlling the flow stress of the material. In this regard, the contents of this work have been categorically organized. First, the active mechanisms in body centered cubic (BCC) low carbon steel during shock loading have been determined as being a composed of the competing mechanisms of dislocations and deformation twins. This has been determined through a series of shock loading tests of the as-received steel. The shock loading tests were done by plate impact experiments at several impact pressures ranging from 2GPa up to 13GPa using a single stage light gas gun. A relationship between twin volume fraction and impact pressure was determined and an analytical model was

  16. Recovery Of Valuable Metals In Tin-Based Anodic Slimes By Carbothermic Reaction

    OpenAIRE

    Han Chulwoong; Kim Young-Min; Son Seong Ho; Choi Hanshin; Kim Tae Bum; Kim Yong Hwan

    2015-01-01

    This study investigated the recovery of anodic slimes by carbothermic reaction in the temperature range of 973~1,273K and amount of carbon as a function of time. Tin anodic slime samples were collected from the bottom of the electrolytic cells during the electro-refining of tin. The anodic slimes are consisted of high concentrated tin, silver, copper and lead oxides. The kinetics of reduction were determined by means of the weight-loss measurement technique. In order to understand in detail o...

  17. 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...

  18. Clay pigment structure characterisation as a guide for provenance determination--a comparison between laboratory powder micro-XRD and synchrotron radiation XRD.

    Science.gov (United States)

    Švarcová, Silvie; Bezdička, Petr; Hradil, David; Hradilová, Janka; Žižak, Ivo

    2011-01-01

    Application of X-ray diffraction (XRD)-based techniques in the analysis of painted artworks is not only beneficial for indisputable identification of crystal constituents in colour layers, but it can also bring insight in material crystal structure, which can be affected by their geological formation, manufacturing procedure or secondary changes. This knowledge might be helpful for art historic evaluation of an artwork as well as for its conservation. By way of example of kaolinite, we show that classification of its crystal structure order based on XRD data is useful for estimation of its provenance. We found kaolinite in the preparation layer of a Gothic wall painting in a Czech church situated near Karlovy Vary, where there are important kaolin deposits. Comparing reference kaolin materials from eight various Czech deposits, we found that these can be differentiated just according to the kaolinite crystallinity. Within this study, we compared laboratory powder X-ray micro-diffraction (micro-XRD) with synchrotron radiation X-ray diffraction analysing the same real sample. We found that both techniques led to the same results.

  19. NMR as a tool for kinetic studies: application to the assessment of organo tin reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Fouquet, E.; Roulet, T. [Bordeaux-1 Univ., 33 - Talence (France); Pianet, I. [Bordeaux-1 Univ., 33 -Talence (France) CNRS, Centre d`Etudes Structurales et d`Analyse des Molecules Organiques; Willem, R. [Brussels University (VUB), Brussels (Belgium)

    1998-02-01

    There is a growing interest for the research of an answer to the environmental problems related to the industrial use of tetra organo tins. An interesting alternative would be to develop the chemistry of mono organo tins because of their lower toxicity and of the easy removal of ``inorganic`` tin side products. In this work, halogen exchange rates are measured for various mono organo tins with NMR techniques (EXSY spectra and 1 D {sup 119} Sn NMR), and an exchange mechanism is proposed. A correlation between kinetic data and the reactivity of the mono organo tins is then exemplified with radical allylic transfer and palladium catalyzed coupling reactions. (authors) 14 refs.

  20. Determination of total tin in silicate rocks by graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Elsheimer, H.N.; Fries, T.L.

    1990-01-01

    A method is described for the determination of total tin in silicate rocks utilizing a graphite furnace atomic absorption spectrometer with a stabilized-temperature platform furnace and Zeeman-effect background correction. The sample is decomposed by lithium metaborate fusion (3 + 1) in graphite crucibles with the melt being dissolved in 7.5% hydrochloric acid. Tin extractions (4 + 1 or 8 + 1) are executed on portions of the acid solutions using a 4% solution of tricotylphosphine oxide in methyl isobutyl ketone (MIBK). Ascorbic acid is added as a reducing agent prior to extraction. A solution of diammonium hydrogenphosphate and magnesium nitrate is used as a matrix modifier in the graphite furnace determination. The limit of detection is > 10 pg, equivalent to > 1 ??g l-1 of tin in the MIBK solution or 0.2-0.3 ??g g-61 in the rock. The concentration range is linear between 2.5 and 500 ??g l-1 tin in solution. The precision, measured as relative standard deviation, is < 20% at the 2.5 ??g l-1 level and < 7% at the 10-30 ??g l-1 level of tin. Excellent agreement with recommended literature values was found when the method was applied to the international silicate rock standards BCR-1, PCC-1, GSP-1, AGV-1, STM-1, JGb-1 and Mica-Fe. Application was made to the determination of tin in geological core samples with total tin concentrations of the order of 1 ??g g-1 or less.