Sample records for measuring blast phenomena

  1. High-speed photography of microscale blast wave phenomena

    NASA Astrophysics Data System (ADS)

    Dewey, John M.; Kleine, Harald

    2005-03-01

    High-speed photography has been a primary tool for the study of blast wave phenomena, dating from the work of Toepler, even before the invention of the camera! High-speed photography was used extensively for the study of blast waves produced by nuclear explosions for which, because of the large scale, cameras running at a few hundred frames per second were adequate to obtain sharp images of the supersonic shock fronts. For the study of the blast waves produced by smaller explosive sources, ever-increasing framing rates were required. As a rough guide, for every three orders of magnitude decrease in charge size a ten-fold increase of framing rate was needed. This severely limited the use of photography for the study of blast waves from laboratory-scale charges. There are many techniques for taking single photographs of explosive phenomena, but the strongly time-dependent development of a blast wave, requires the ability to record a high-speed sequence of photographs of a single event. At ICHSPP25, Kondo et al of Shimadzu Corporation demonstrated a 1 M fps video camera that provides a sequence of up to 100 high-resolution frames. This was subsequently used at the Shock Wave Research Center of Tohoku University to record the blast waves generated by an extensive series of silver azide charges ranging in size from 10 to 0.5mg. The resulting images were measured to provide radius-time histories of the primary and secondary shocks. These were analyzed with techniques similar to those used for the study of explosions from charges with masses ranging from 500 kg to 5 kt. The analyses showed the cube-root scaling laws to be valid for the very small charges, and provided a detailed record of the peak hydrostatic pressure as a function of radius for a unit charge of silver azide, over a wide range of scaled distances. The pressure-radius variation was compared to that from a unit charge of TNT and this permitted a detailed determination of the TNT equivalence of silver azide as a function of peak pressure and radius. The availability of the Shimadzu high-speed framing camera has made it possible to perform experiments at the laboratory scale that previously could be done only on large-scale field trials. At the laboratory scale, many experiments can be performed on the same day, as compared to the months or even years required for the preparation of large-scale field experiments. The economic savings are even greater.

  2. Measurements design and phenomena discrimination

    E-print Network

    Laura Rebollo-Neira

    2009-08-05

    The construction of measurements suitable for discriminating signal components produced by phenomena of different types is considered. The required measurements should be capable of cancelling out those signal components which are to be ignored when focusing on a phenomenon of interest. Under the hypothesis that the subspaces hosting the signal components produced by each phenomenon are complementary, their discrimination is accomplished by measurements giving rise to the appropriate oblique projector operator. The subspace onto which the operator should project is selected by nonlinear techniques in line with adaptive pursuit strategies.

  3. Rapid miniature fiber optic pressure sensors for blast wave measurements

    NASA Astrophysics Data System (ADS)

    Zou, Xiaotian; Wu, Nan; Tian, Ye; Niezrecki, Christopher; Chen, Julie; Wang, Xingwei

    2013-02-01

    Traumatic brain injury (TBI) is a serious potential threat to soldiers who are exposed to explosions. Since the pathophysiology of TBI associated with a blast wave is not clearly defined, it is crucial to have a sensing system to accurately quantify the blast wave dynamics. This paper presents an ultra-fast fiber optic pressure sensor based on Fabry-Perot (FP) interferometric principle that is capable of measuring the rapid pressure changes in a blast event. The blast event in the experiment was generated by a starter pistol blank firing at close range, which produced a more realistic wave profile compared to using compressed air driven shock tubes. To the authors' knowledge, it is also the first study to utilize fiber optic pressure sensors to measure the ballistics shock wave of a pistol firing. The results illustrated that the fiber optic pressure sensor has a rise time of 200 ns which demonstrated that the sensor has ability to capture the dynamic pressure transient during a blast event. Moreover, the resonant frequency of the sensor was determined to be 4.11 MHz, which agrees well with the specific designed value.

  4. Measurement of Blast Waves from Bursting Pressureized Frangible Spheres

    NASA Technical Reports Server (NTRS)

    Esparza, E. D.; Baker, W. E.

    1977-01-01

    Small-scale experiments were conducted to obtain data on incident overpressure at various distances from bursting pressurized spheres. Complete time histories of blast overpressure generated by rupturing glass spheres under high internal pressure were obtained using eight side-on pressure transducers. A scaling law is presented, and its nondimensional parameters are used to compare peak overpressures, arrival times, impulses, and durations for different initial conditions and sizes of blast source. The nondimensional data are also compared, whenever possible, with results of theoretical calculations and compiled data for Pentolite high explosive. The scaled data are repeatable and show significant differences from blast waves generated by condensed high-explosives.

  5. Develop of the Blast Furnace Soft Water Temperature Measurement System

    Microsoft Academic Search

    Zhang Lei; Zhou Fei; Qian Ya-ping

    2008-01-01

    In order to ensure normal operation of the blast furnace (BF) closed loop soft water cooling system, cooling water temperature and the heat load must be controlled. It is the most important how the hundreds of large-scale blast furnace soft water temperature points for real-time detection. The DS18B20 digital thermometer was used as a temperature sensor. The DS18B20 communicates over

  6. Scattering phenomena in MSCT: measurements and analysis

    NASA Astrophysics Data System (ADS)

    Sabo-Napadensky, I.; Amir, O.

    2007-03-01

    In multi-slice CT (MSCT), as the coverage becomes wider, the scattering contribution along the longitudinal direction (z) to the detectors' signal increases. The scattering results in image artifacts, appearing as dark shadows between highly attenuating objects. In this work we measure the scattering level systematically, using phantoms of various sizes, shapes, and materials. We study the dependencies and their effect on the scattering amount. We derive an empirical function for the scattering fraction, based on the maximal attenuation at each rotation angle. The function contains a single constant (SC). The variation of SC as a function of the different phantoms is analyzed, showing a clear dependence on the minimal water equivalent axis of each phantom. The strong dependence of the scattering fraction on the maximal attenuation along each view is shown. This phenomenon can be correlated to a single scatter process along the z axis in the presence of an anti-scatter grid along the direction of the detectors. The dependence of SC on the minimal axis indicates an additional significant scatter process. The results validate that the scattering level estimation can be achieved using the derived function, with a minimal variation in the solution parameters. Hence, enabling the introduction of this scatter estimation into an MSCT scattering correction scheme.

  7. Spatially-resolved X-ray scattering measurements of a planar blast wave

    NASA Astrophysics Data System (ADS)

    Gamboa, E. J.; Keiter, P. A.; Drake, R. P.; Falk, K.; Montgomery, D. S.; Benage, J. F.

    2014-06-01

    We present X-ray scattering measurements characterizing the spatial temperature and ionization profile of a blast wave driven in a near-solid density foam. Several-keV X-rays scattered from a laser-driven blast wave in a carbon foam. We resolved the scattering in high resolution in space and wavelength to extract the plasma conditions along the propagation direction of the blast wave. We infer temperatures of 20-40 eV and ionizations of 2-4 in the shock and rarefaction regions of the blast wave. This range of measured ionization states allows for a detailed comparison between different models for the bound-free scattering. FLYCHK simulations of the temperature-ionization balance generally agree with the experimental values in the shocked region while consistently underestimating the ionization in the rarefaction.

  8. On-line ultrasonic system for measuring thickness of the copper stave in the blast furnace

    NASA Astrophysics Data System (ADS)

    Choi, Sang-Woo; Kim, Dohoon

    2012-05-01

    The blast furnace is used make molten iron from sintered ore and the cokes in the steel industry. Recently, the copper stave cooling system placed on inner face of the blast furnace body to protect the steel shell from heat. In the high temperature environment, the wear between the stave and the material makes the cooling stave thinning by the downward movement of the materials in the blast furnace. It was impossible to access the copper stave with the ultrasonic sensor for measuring thickness because the copper stave is covered with the steel shell and there is backing refractory between the stave and the steel shell. The unique ultrasonic sensor which can approach the cooling stave through the cooling line was developed to measure thickness. The thickness can be measured with portable ultrasonic thickness sensor and can be monitored continuously with embedded sensors.

  9. High spatial resolution measurements of ram accelerator gas dynamic phenomena

    NASA Technical Reports Server (NTRS)

    Hinkey, J. B.; Burnham, E. A.; Bruckner, A. P.

    1992-01-01

    High spatial resolution experimental tube wall pressure measurements of ram accelerator gas dynamic phenomena are presented. The projectile resembles the centerbody of a ramjet and travels supersonically through a tube filled with a combustible gaseous mixture, with the tube acting as the outer cowling. Pressure data are recorded as the projectile passes by sensors mounted in the tube wall at various locations along the tube. Data obtained by using a special highly instrumented section of tube has allowed the recording of gas dynamic phenomena with a spatial resolution on the order of one tenth the projectile length. High spatial resolution tube wall pressure data from the three regimes of propulsion studied to date (subdetonative, transdetonative, and superdetonative) are presented and reveal the 3D character of the flowfield induced by projectile fins and the canting of the projectile body relative to the tube wall. Also presented for comparison to the experimental data are calculations made with an inviscid, 3D CFD code.

  10. Simultaneous Measurements of Temperature and Iron-Slag Ratio at Taphole of Blast Furnace

    NASA Astrophysics Data System (ADS)

    Sugiura, M.; Shinotake, A.; Nakashima, M.; Omoto, N.

    2014-07-01

    As the initial process in an integrated steel-making plant, molten iron is produced in a blast furnace. The molten iron has a temperature between 1700 K and 1900 K. The outflow stream discharged from a taphole comprises the molten iron and slag (which is a mixture of molten oxides). Monitoring of the stream temperature is important because it has information on the thermal condition inside the blast furnace. A newly developed simultaneous measurement technique for temperature and iron-slag ratio is reported. A monochromatic CCD camera with a short exposure time is used to obtain a thermal image of the rapidly moving stream. The thermal image has a marble-like pattern caused by the physical separation of the iron and slag and their different optical properties. Iron thermometry is realized by automatically detecting the peak of the iron gray-level distribution on a histogram. Meanwhile, the thermal radiance of the semitransparent slag varies as a function of the thickness. The slag temperature is calculated from the maximum gray level, presuming that the emissivity of the slag is constant at a thick slag part. The slag ratio is measured by counting the number of pixels on the histogram. A field test was carried out at an operating blast furnace. The iron temperature, slag temperature, and slag ratio were successfully measured. This multiple image measurement is expected to be the new information source for stable blast furnace operation.

  11. Investigation of atmospheric blasts by fast radiometry

    NASA Astrophysics Data System (ADS)

    Ben-Dov, R.; Bushlin, Y.; Devir, A. D.; Lessin, A. B.; Mendelewicz, I.; Shvebelman, M.

    2014-06-01

    Blasts and detonations release large amount of energy in short time duration. Some of this energy is released through radiation in the whole optical spectrum. Measurement of this radiation may serve as a base for investigation of the blast phenomena. A fast multispectral radiometer that operates in proper chosen spectral bands provides extensive information on the physical processes that govern the blast. This information includes the time dependence of the temperature, area of the blast as-well-as of the aerosols and gases that are generated. Analysis of this data indicates the order of the detonation and provides good estimation on the masses and types of the high-explosives (HE) materials and their casing. This paper presents the methodology and instrumentation of fast multispectral radiometry in application to the blast measurement and analysis in a Near-ground Explosion Test (NET). In NET, the flash radiation of the blast was measured for two HE materials: TNT and composition B (CB). The investigation includes charges of different masses (0.25 - 20.0 kg) and of various casing materials (steel, Al, PVC), thickness (2 - 6 mm) and various casing type (open on both face ends and hermetically closed). Analysis of the data demonstrates the power of fast radiometry methodology and reveals the governing characteristics of atmospheric blasts.

  12. Correlating Multi-Phenomenology Measurements with Blast Design in a Copper Mine Chris Hayward and Brian Stump, Department of Geological Sciences, Southern Methodist University

    E-print Network

    Stump, Brian W.

    1 Correlating Multi-Phenomenology Measurements with Blast Design in a Copper Mine Chris Hayward Dodge Morenci, Inc. Blasting operations at one copper mine are studied in detail to examine the relation between blast design parameters and near-shot, in-mine, and regional seismic and acoustic observations

  13. Low-cost rapid miniature optical pressure sensors for blast wave measurements.

    PubMed

    Wu, Nan; Wang, Wenhui; Tian, Ye; Zou, Xiaotian; Maffeo, Michael; Niezrecki, Christopher; Chen, Julie; Wang, Xingwei

    2011-05-23

    This paper presents an optical pressure sensor based on a Fabry-Perot (FP) interferometer formed by a 45° angle polished single mode fiber and an external silicon nitride diaphragm. The sensor is comprised of two V-shape grooves with different widths on a silicon chip, a silicon nitride diaphragm released on the surface of the wider V-groove, and a 45° angle polished single mode fiber. The sensor is especially suitable for blast wave measurements: its compact structure ensures a high spatial resolution; its thin diaphragm based design and the optical demodulation scheme allow a fast response to the rapid changing signals experienced during blast events. The sensor shows linearity with the correlation coefficient of 0.9999 as well as a hysteresis of less than 0.3%. The shock tube test demonstrated that the sensor has a rise time of less than 2 µs from 0 kPa to 140 kPa. PMID:21643336

  14. NASA CONNECT: Data Analysis and Measurement - Having a Solar Blast

    NSDL National Science Digital Library

    2002-01-01

    In this program, students learn how NASA researchers study the Sun-Earth connection. Students learn about satellites that monitor the Sun: (Solar & Heliospheric Observatory) SOHO, Advanced Composition Explorer (ACE), and Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) and (Highg Energy Solar Spectrostopic Imager) HESSI. They observe NASA researchers using data analysis and measurement to determine the solar cycle of the Sun. By conducting hands-on and web activities, students make connections between NASA research and the mathematics, science, and technology they learn in their classrooms. The program consists of two parts: a 30-minute video and an on-line educators guide.

  15. Precise Measurement of Deuteron Tensor Analyzing Powers with BLAST

    SciTech Connect

    Zhang, C.; Akdogan, T.; Bertozzi, W.; Botto, T.; Clasie, B.; DeGrush, A.; Dow, K.; Farkhondeh, M.; Franklin, W.; Gilad, S.; Hasell, D.; Kolster, H.; Maschinot, A.; Matthews, J.; Meitanis, N.; Milner, R.; Redwine, R.; Seely, J.; Shinozaki, A.; Tschalaer, C. [Laboratory for Nuclear Science and Bates Linear Accelerator Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2011-12-16

    We report a precision measurement of the deuteron tensor analyzing powers T{sub 20} and T{sub 21} at the MIT-Bates Linear Accelerator Center. Data were collected simultaneously over a momentum transfer range Q=2.15-4.50 fm{sup -1} with the Bates Large Acceptance Spectrometer Toroid using a highly polarized deuterium internal gas target. The data are in excellent agreement with calculations in a framework of effective field theory. The deuteron charge monopole and quadrupole form factors G{sub C} and G{sub Q} were separated with improved precision, and the location of the first node of G{sub C} was confirmed at Q=4.19{+-}0.05 fm{sup -1}. The new data provide a strong constraint on theoretical models in a momentum transfer range covering the minimum of T{sub 20} and the first node of G{sub C}.

  16. BLAST: A FAR-INFRARED MEASUREMENT OF THE HISTORY OF STAR FORMATION

    SciTech Connect

    Pascale, Enzo; Ade, Peter A. R.; Dye, Simon; Eales, Steve A.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip; Moncelsi, Lorenzo [School of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff, CF24 3AA (United Kingdom); Bock, James J. [Jet Propulsion Laboratory, Pasadena, CA 91109-8099 (United States); Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen; Ngo, Henry [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Devlin, Mark J.; Klein, Jeff [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA, 19104 (United States); Gundersen, Joshua O. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Hughes, David H. [Instituto Nacional de AstrofIsica Optica y Electronica (INAOE), Aptdo. Postal 51 y 72000 Puebla (Mexico); Netterfield, Calvin B. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street Toronto, ON M5S 3H4 (Canada); Olmi, Luca [University of Puerto Rico, Rio Piedras Campus, Physics Department, Box 23343, UPR station, PR 00931 (United States); Patanchon, Guillaume, E-mail: enzo.pascale@astro.cf.ac.u [Universite Paris Diderot, Laboratoire APC, 10, rue Alice Domon et Leonie Duquet 75205 Paris (France)

    2009-12-20

    We directly measure redshift evolution in the mean physical properties (far-infrared luminosity, temperature, and mass) of the galaxies that produce the cosmic infrared background (CIB), using measurements from the Balloon-borne Large Aperture Submillimeter Telescope (BLAST), and Spitzer which constrain the CIB emission peak. This sample is known to produce a surface brightness in the BLAST bands consistent with the full CIB, and photometric redshifts are identified for all of the objects. We find that most of the 70 mum background is generated at z approx< 1 and the 500 mum background generated at z approx> 1. A significant growth is observed in the mean luminosity from approx10{sup 9}-10{sup 12} L{sub sun}, and in the mean temperature by 10 K, from redshifts 0 < z < 3. However, there is only weak positive evolution in the comoving dust mass in these galaxies across the same redshift range. We also measure the evolution of the far-infrared luminosity density, and the star formation rate history for these objects, finding good agreement with other infrared studies up to z approx 1, exceeding the contribution attributed to optically selected galaxies.

  17. An Undergraduate Experiment for the Measurement of the Speed of Sound in Air: Phenomena and Discussion

    ERIC Educational Resources Information Center

    Yang, Hujiang; Zhao, Xiaohong; Wang, Xin; Xiao, Jinghua

    2012-01-01

    In this paper, we present and discuss some phenomena in an undergraduate experiment for the measurement of the speed of sound in air. A square wave distorts when connected to a piezoelectric transducer. Moreover, the amplitude of the receiving signal varies with the driving frequency. Comparing with the Gibbs phenomenon, these phenomena can be…

  18. Correlating Multi-Phenomenology Measurements with Blast Design in a Copper Mine Sponsored by Defense Threat Reduction Agency

    E-print Network

    Stump, Brian W.

    Correlating Multi-Phenomenology Measurements with Blast Design in a Copper Mine Sponsored by Defense Threat Reduction Agency Contract DSWA01-98-C-0176 The Mine The cooperating mine was the Morenci Mine operated by Phelps-Dodge in SE Arizona. The scale of the operation is illustrated below. The mine

  19. Measuring transient high temperature thermal phenomena in hostile environment

    SciTech Connect

    Brenden, B.B.; Hartman, J.S.; Reich, F.R.

    1980-01-01

    The design of equipment for measuring temperature and strain in a rapidly heated and pressurized cylinder of stainless steel is discussed. Simultaneous cinematography of the full circumference of the cylinder without interference with temperature and strain measurements is also illustrated. The integrated system uses a reflective chamber for the sample and requires careful consideration of the spectral energy distribution utilized by each instrument.

  20. Mold Slag Property Measurements to Characterize CC Mold Shell Gap Phenomena , B.G. Thomas1

    E-print Network

    Thomas, Brian G.

    Mold Slag Property Measurements to Characterize CC Mold ­ Shell Gap Phenomena Y. Meng1 , B, Edmonton, Canada Keywords: Mold flux, Mold slag, Measurements, Friction coefficient, Viscosity, CCT, Modeling Abstract Multi-faceted experiments were conducted to measure the properties of several mold slags

  1. The measurements of thermoacoustic phenomena using thermoacoustic couples

    NASA Astrophysics Data System (ADS)

    Ao, Chia-Ning

    1989-06-01

    Thermoacoustic heat transport and its applications, such as thermoacoustic engines and refrigerators, have been discussed in a number of articles over the past several years. However, lacking from these articles is a thorough, quantitative experimental investigation of the basic theory underlying thermoacoustic heat transport. Such an investigation is the purpose of this thesis. A logical starting point for such a study is to investigate the simplest class of thermoacoustic engine - a stack of short plates referred to as a ThermoAcoustic Couple, or TAC. The utility of this choice is that the theory can be reduced to its simplest form for analysis of the results. The results of measurements of thermoacoustically generated temperature gradients in TACs subjected to acoustic standing waves are reported. The value of the temperature gradient, which results from an acoustically generated entropy flow in the gas in thermal contact with the plate, is a function of the acoustic pressure amplitude, the mean gas pressure, the Prandtl number of the gas, the configuration of the TAC, and its position in the standing wave. Measurements were made with a computer controlled apparatus for drive ratios (the ratio of the acoustic pressure amplitude to the mean pressure of the gas) from approximately 0.1 to 2 percent, in argon and helium having mean standing wave.

  2. Blast investigation by fast multispectral radiometric analysis

    Microsoft Academic Search

    A. D. Devir; Y. Bushlin; I. Mendelewicz; A. B. Lessin; M. Engel

    2011-01-01

    Knowledge regarding the processes involved in blasts and detonations is required in various applications, e.g. missile interception, blasts of high-explosive materials, final ballistics and IED identification. Blasts release large amount of energy in short time duration. Some part of this energy is released as intense radiation in the optical spectral bands. This paper proposes to measure the blast radiation by

  3. Measuring the velocities of particles in a shot-blasting chamber

    NASA Astrophysics Data System (ADS)

    Bombek, G.; Hribernik, A.

    2010-08-01

    This paper presents a method for measuring the velocity of a flow of particles accelerated on a shot-blasting wheel and then expanding into space at a wide angle of approximately 45°. The method uses the pulsed nature of the flow characteristic for turbo machinery with a finite number of wheel blades and calculates the velocity from the time shift between the particles hitting two targets at a known distance. This method does not depend on the material properties of the particles; however, a large number of particles is required for a successful measurement. The impacts are detected with a microphone covered by a steel membrane, making the exposed parts cheap and easily replaceable. This makes the method suitable for industrial test-and-development purposes, including the efficiencies of acceleration measurements. A cross-correlation of the signals was used, but the characteristic cycle (one rotation of the wheel) had to be determined beforehand by overlapping and averaging several cycles in order to compensate for the fact that different particles would be hitting the targets.

  4. Pressure-sensitive paint measurements of transient shock phenomena.

    PubMed

    Quinn, Mark Kenneth; Kontis, Konstantinos

    2013-01-01

    Measurements of the global pressure field created by shock wave diffraction have been captured optically using a porous pressure-sensitive paint. The pressure field created by a diffracting shock wave shows large increases and decreases in pressure and can be reasonably accurately captured using CFD. The substrate, a thin-layer chromatography (TLC) plate, has been dipped in a luminophore solution. TLC plates are readily available and easy to prepare. Illumination comes from two high-intensity broadband Xenon arc light sources with short-pass filters. The sample is imaged at 100 kHz using a Vision Research Phantom V710 in conjunction with a pair of long and short pass filters, creating a band. The PSP results are compared with numerical simulations of the flow using the commercial CFD package Fluent as part of ANSYS 13 for two Mach numbers. PMID:23549365

  5. MEASUREMENTS OF MOLTEN STEEL/FLUX INTERFACE PHENOMENA IN THIN SLAB CASTING

    E-print Network

    Thomas, Brian G.

    MEASUREMENTS OF MOLTEN STEEL/FLUX INTERFACE PHENOMENA IN THIN SLAB CASTING By Joseph W. Shaver B trials investigating meniscus behavior and defects in thin-slab casting were conducted at Nucor Steel of the steel. Metal level and meniscus measurements were made during ordinary casting operation. Nailboards

  6. Blast Injuries

    MedlinePLUS

    ... DVBIC & TBI Educational Materials Research DVBIC Locations Press Blast Injuries (U.S. Army photo by Sgt. Gustavo Olgiati) ... games. More Information: 04/12/11: Research Examines Blast Impact on Human Brain 04/06/09: Military ...

  7. Operation Greenhouse. Scientific Director's report of atomic weapon tests at Eniwetok, 1951. Annex 1. 6, blast measurements. Part 3. Pressure near ground level. Section 4. Blast asymmetry from aerial photographs. Section 5. Ball-crusher-gauge measurements of peak pressure

    SciTech Connect

    Not Available

    1985-04-01

    Aerial motion pictures from manned aircraft were taken of the Dog, Easy, and George Shots and from a drone aircraft on Dog Shot to determine whether asymmetries in the blast waves could be detected and measured. Only one film, that taken of Dog Shot from a drone, was considered good enough to warrant detailed analysis, but this failed to yield any positive information on asymmetries. The analysis showed that failure to obtain good arrival-time data arose from a number of cases, but primarily from uncertainities in magnification and timing. Results could only be matched with reliable data from blast-velocity switches by use of large corrections. Asymnetries, if present, were judged to have been too small or to have occurred too early to be detected with the slow-frame speed used. Recommendations for better results include locating the aircraft directly overhead at the time of burst and using a camera having greater frame speed and provided with timing marks.

  8. Quantitative limits of thermal and fluid phenomena measurements using the neutron attenuation characteristics of materials

    Microsoft Academic Search

    K. Mishima; T. Hibiki

    1996-01-01

    Temporal and spatial resolution of the neutron radiographic technique were investigated in order to apply this technique to the visualization and measurement of thermal and fluid phenomena. The temporal resolution of three imaging methods of temporally resolved neutron radiography-static neutron radiography with a pulsed neutron beam and high frame rate neutron radiography with either a pulsed or steady neutron beam-was

  9. Air blast parameters from summer and winter 20-ton TNT explosions, Operation Distant Plain, Events 3 and 5. Memorandum report

    Microsoft Academic Search

    R. E. Reisler; L. Giglio-Tos; G. D. Teel; D. P. LeFevre

    1967-01-01

    Air blast was measured from the detonation of two 20-ton spherical TNT charges positioned with the center of gravity at the air-ground interface. The detonations occurred in an area having a silty-clay alluvium composition. One charge was fired in the summer and the other was fired in the winter when the ground was frozen. Differences in the air blast phenomena

  10. MEASUREMENT OF AIR BLAST EFFECTS FROM SIMULATED NUCLEAR REACTOR CORE EXCURSIONS

    Microsoft Academic Search

    R. J. Larson; W. C. Olson

    1957-01-01

    Tests were conducted to evaluate methods of simulating on a small scale, ; the effect of nuclear reactor runaway'' on a containment shell surrounding the ; reactor. Reactor core vessels, simulated by small pressure tanks, were burst by ; chemical reactions of various rates, and the resulting pressure-time histories ; were recorded by piezoelectric air blast gages placed at various

  11. Blast Testing Issues and TBI: Experimental Models That Lead to Wrong Conclusions

    PubMed Central

    Needham, Charles E.; Ritzel, David; Rule, Gregory T.; Wiri, Suthee; Young, Leanne

    2015-01-01

    Over the past several years, we have noticed an increase in the number of blast injury studies published in peer-reviewed biomedical journals that have utilized improperly conceived experiments. Data from these studies will lead to false conclusions and more confusion than advancement in the understanding of blast injury, particularly blast neurotrauma. Computational methods to properly characterize the blast environment have been available for decades. These methods, combined with a basic understanding of blast wave phenomena, enable researchers to extract useful information from well-documented experiments. This basic understanding must include the differences and interrelationships of static pressure, dynamic pressure, reflected pressure, and total or stagnation pressure in transient shockwave flows, how they relate to loading of objects, and how they are properly measured. However, it is critical that the research community effectively overcomes the confusion that has been compounded by a misunderstanding of the differences between the loading produced by a free field explosive blast and loading produced by a conventional shock tube. The principles of blast scaling have been well established for decades and when properly applied will do much to repair these problems. This paper provides guidance regarding proper experimental methods and offers insights into the implications of improperly designed and executed tests. Through application of computational methods, useful data can be extracted from well-documented historical tests, and future work can be conducted in a way to maximize the effectiveness and use of valuable biological test data.

  12. Design Considerations for Remote High-Speed Pressure Measurements of Dynamic Combustion Phenomena

    SciTech Connect

    Straub, D.L.; Ferguson, D.H.; Rohrssen, Robert (West Virginia University, Morgantown, WV); Perez, Eduardo (West Virginia University, Morgantown, WV)

    2007-01-01

    As gas turbine combustion systems evolve to achieve ultra-low emission targets, monitoring and controlling dynamic combustion processes becomes increasingly important. These dynamic processes may include flame extinction, combustion-driven instabilities, or other dynamic combustion phenomena. Pressure sensors can be incorporated into the combustor liner design, but this approach is complicated by the harsh operating environment. One practical solution involves locating the sensor in a more remote location, such as outside the pressure casing. The sensor can be connected to the measurement point by small diameter tubing. Although this is a practical approach, the dynamics of the tubing can introduce significant errors into the pressure measurement. This paper addresses measurement errors associated with semi-infinite coil remote sensing setups and proposes an approach to improve the accuracy of these types of measurements.

  13. Measurements of blast waves from bursting frangible spheres pressurized with flash-evaporation vapor or liquid

    NASA Technical Reports Server (NTRS)

    Esparaza, E. D.; Baker, W. E.

    1977-01-01

    Incident overpressure data from frangible spheres pressurized with a flash-evaporating fluid in liquid and vapor form were obtained in laboratory experiments. Glass spheres under higher than ambient internal pressure of Freon-12 were purposely burst to obtain time histories of overpressure. Nondimensional peak pressures, arrival and duration times, and impulses are presented, and whenever possible plotted and compared with compiled data for Pentolite high-explosive. The data are generally quite repeatable and show differences from blast data produced by condensed high-explosives.

  14. Nuclear Blast

    MedlinePLUS

    ... more susceptible to blast effects. Existing meteorological conditions. Wind speed and direction will affect arrival time of ... from a nuclear explosion may be carried by wind currents for hundreds of miles if the right ...

  15. Flow Measurement in Helical Inducer and Estimate of Fluctuating Blade Force in Cavitation Surge Phenomena

    NASA Astrophysics Data System (ADS)

    Furukawa, Akinori; Ishizaka, Koichi; Watanabe, Satoshi

    An attachment of inducer is a powerful method to improve the cavitation performance of a turbo-pump. Cavitation surge phenomena, occurring under the severe suction pressure at a partial flow rate, is focused in the present paper. Flow measurements were carried out at the inlet and outlet sections of a flat-plate helical inducer with the solidity of 2.0 and tip blade angle of 11° by using a total-head yaw-meter with a phase locked sampling method in one period of the shaft rotation or the cavitation oscillation. Time variation of the flow distributions during the oscillation is clarified with observed cavitation behaviors. After these results are compared with those in conditions just before and after the oscillations, the fluctuating blade forces are estimated from the blade to blade distributions of casing wall pressures measured in these conditions.

  16. Determination of constant-volume balloon capabilities for aeronautical research. [specifically measurement of atmospheric phenomena

    NASA Technical Reports Server (NTRS)

    Tatom, F. B.; King, R. L.

    1977-01-01

    The proper application of constant-volume balloons (CVB) for measurement of atmospheric phenomena was determined. And with the proper interpretation of the resulting data. A literature survey covering 176 references is included. the governing equations describing the three-dimensional motion of a CVB immersed in a flow field are developed. The flowfield model is periodic, three-dimensional, and nonhomogeneous, with mean translational motion. The balloon motion and flow field equations are cast into dimensionless form for greater generality, and certain significant dimensionless groups are identified. An alternate treatment of the balloon motion, based on first-order perturbation analysis, is also presented. A description of the digital computer program, BALLOON, used for numerically integrating the governing equations is provided.

  17. Measurement of the Decay Rate of Single-Frequency Perturbations on Blast Waves A. D. Edens* and T. Ditmire

    E-print Network

    Ditmire, Todd

    into an external medium and on the other by the thermal pressure of hot gas inside the blast wave. Ryu and Vishniac 500 m diameter nylon target pin immersed in 10 Torr of nitrogen gas. The resulting explosion from

  18. BLAST: THE REDSHIFT SURVEY

    SciTech Connect

    Eales, Stephen; Dye, Simon; Mauskopf, Philip; Moncelsi, Lorenzo; Pascale, Enzo; Raymond, Gwenifer [Cardiff University, School of Physics and Astronomy, Queens Buildings, The Parade, Cardiff, CF24 3AA (United Kingdom); Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen; Scott, Douglas [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Devlin, Mark J.; Rex, Marie; Semisch, Christopher; Truch, Matthew D. P. [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia PA, 19104 (United States); Hughes, David H. [Instituto Nacional de AstrofIsica Optica y Electronica (INAOE), Aptdo. Postal 51 y 72000 Puebla (Mexico); Netterfield, Calvin B.; Viero, Marco P. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street Toronto, ON M5S 3H4 (Canada); Patanchon, Guillaume [Universite Paris Diderot, Laboratoire APC, 10, rue Alice Domon et Leonie Duquet 75205 Paris (France); Siana, Brian [California Institute of Technology, MS 105-24, Pasadena, CA 91125 (United States)

    2009-12-20

    The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) has recently surveyed approx =8.7 deg{sup 2} centered on Great Observatories Origins Deep Survey-South at 250, 350, and 500 mum. In Dye et al., we presented the catalog of sources detected at 5sigma in at least one band in this field and the probable counterparts to these sources in other wavebands. In this paper, we present the results of a redshift survey in which we succeeded in measuring redshifts for 82 of these counterparts. The spectra show that the BLAST counterparts are mostly star-forming galaxies but not extreme ones when compared to those found in the Sloan Digital Sky Survey. Roughly one quarter of the BLAST counterparts contain an active nucleus. We have used the spectroscopic redshifts to carry out a test of the ability of photometric redshift methods to estimate the redshifts of dusty galaxies, showing that the standard methods work well even when a galaxy contains a large amount of dust. We have also investigated the cases where there are two possible counterparts to the BLAST source, finding that in at least half of these there is evidence that the two galaxies are physically associated, either because they are interacting or because they are in the same large-scale structure. Finally, we have made the first direct measurements of the luminosity function in the three BLAST bands. We find strong evolution out to z = 1, in the sense that there is a large increase in the space density of the most luminous galaxies. We have also investigated the evolution of the dust-mass function, finding similar strong evolution in the space density of the galaxies with the largest dust masses, showing that the luminosity evolution seen in many wavebands is associated with an increase in the reservoir of interstellar matter in galaxies.

  19. Blast injury.

    PubMed

    de Candole, C A

    1967-01-28

    The shock wave generated by an explosion ("blast wave") may cause injury in any or all of the following: (1) direct impact on the tissues of variations in environmental pressure; (2) flying glass and other debris set in motion by it; (3) propulsion of the body. Injuries in the first category affect gas-containing organs (ears, lungs and intestines), and acute death is attributed to air forced into the coronary vessels via damaged pulmonary alveoli. It is estimated that overpressure sufficient to cause lung injury may occur up to five miles from a 20-megaton nuclear explosion. The greatest single hazard from blast is, however, flying glass, and serious wounding from this cause is possible up to 12 miles from an explosion of this magnitude. PMID:6015742

  20. Blast Injury

    PubMed Central

    de Candole, C. A.

    1967-01-01

    The shock wave generated by an explosion (“blast wave”) may cause injury in any or all of the following: (1) direct impact on the tissues of variations in environmental pressure; (2) flying glass and other debris set in motion by it; (3) propulsion of the body. Injuries in the first category affect gas-containing organs (ears, lungs and intestines), and acute death is attributed to air forced into the coronary vessels via damaged pulmonary alveoli. It is estimated that overpressure sufficient to cause lung injury may occur up to five miles from a 20-megaton nuclear explosion. The greatest single hazard from blast is, however, flying glass, and serious wounding from this cause is possible up to 12 miles from an explosion of this magnitude. PMID:6015742

  1. PIV Experiments to Measure Flow Phenomena in a Scaled Model of a VHTR Lower Plenum

    SciTech Connect

    Hugh M. McIlroy, Jr.; Donald M. McEligot; Richard R. Schultz; Daniel Christensen; Robert J. Pink; Ryan C. Johnson

    2006-09-01

    A report of experimental data collected at the Matched-Index-of-Refraction (MIR) Laboratory in support of contract DE-AC07-05ID14517 and the INL Standard Problem on measurements of flow phenomena occurring in a lower plenum of a typical prismatic VHTR concept reactor to assess CFD code is presented. Background on the experimental setup and procedures is provided along with several samples of data obtained from the 3-D PIV system and an assessment of experimental uncertainty is provided. Data collected in this study include 3-dimensional velocity-field descriptions of the flow in all four inlet jets and the entire lower plenum with inlet jet Reynolds numbers (ReJet) of approximately 4300 and 12,400. These investigations have generated over 2 terabytes of data that has been processed to describe the various velocity components in formats suitable for external release and archived on removable hard disks. The processed data from both experimental studies are available in multi-column text format.

  2. Flight test measurements and analysis of sonic boom phenomena near the shock wave extremity

    NASA Technical Reports Server (NTRS)

    Haglund, G. T.; Kane, E. J.

    1973-01-01

    The sonic boom flight test program conducted at Jackass Flats, Nevada, during the summer and fall of 1970 consisted of 121 sonic-boom-generating flights over the 1500 ft instrumented BREN tower. This test program was designed to provide information on several aspects of sonic boom, including caustics produced by longitudinal accelerations, caustics produced by steady flight near the threshold Mach number, sonic boom characteristics near lateral cutoff, and the vertical extent of shock waves attached to near-sonic airplanes. The measured test data, except for the near-sonic flight data, were analyzed in detail to determine sonic boom characteristics for these flight conditions and to determine the accuracy and the range of validity of linear sonic boom theory. The caustic phenomena observed during the threshold Mach number flights and during the transonic acceleration flights are documented and analyzed in detail. The theory of geometric acoustics is shown to be capable of predicting shock wave-ground intersections, and current methods for calculating sonic boom pressure signature away from caustics are shown to be reasonably accurate.

  3. Fluid dynamics of the 1997 Boxing Day volcanic blast on Montserrat, West Indies

    Microsoft Academic Search

    T. Esposti Ongaro; A. B. Clarke; A. Neri; B. Voight; C. Widiwijayanti

    2008-01-01

    Directed volcanic blasts are powerful explosions with a significant laterally directed component, which can generate devastating, high-energy pyroclastic density currents (PDCs). Such blasts are an important class of eruptive phenomena, but quantified understanding of their dynamics and effects is still incomplete. Here we use 2-D and 3-D multiparticle thermofluid dynamic flow codes to examine a powerful volcanic blast that occurred

  4. Measurement of Flow Phenomena in a Lower Plenum Model of a Prismatic Gas-Cooled Reactor

    SciTech Connect

    Hugh M. McIlroy, Jr.; Donald M. McEligot; Robert J. Pink

    2008-05-01

    Mean-velocity-field and turbulence data are presented that measure turbulent flow phenomena in an approximately 1:7 scale model of a region of the lower plenum of a typical prismatic gas-cooled reactor (GCR) similar to a General Atomics Gas-Turbine-Modular Helium Reactor (GTMHR) design. The data were obtained in the Matched-Index-of-Refraction (MIR) facility at Idaho National Laboratory (INL) and are offered for assessing computational fluid dynamics (CFD) software. This experiment has been selected as the first Standard Problem endorsed by the Generation IV International Forum. This paper reviews the experimental apparatus and procedures, presents a sample of the data set, and reviews the INL Standard Problem. Results concentrate on the region of the lower plenum near its far reflector wall (away from the outlet duct). The flow in the lower plenum consists of multiple jets injected into a confined cross flow - with obstructions. The model consists of a row of full circular posts along its centerline with half-posts on the two parallel walls to approximate flow scaled to that expected from the staggered parallel rows of posts in the reactor design. The model is fabricated from clear, fused quartz to match the refractive-index of the mineral oil working fluid so that optical techniques may be employed for the measurements. The benefit of the MIR technique is that it permits optical measurements to determine flow characteristics in complex passages in and around objects to be obtained without locating intrusive transducers that will disturb the flow field and without distortion of the optical paths. An advantage of the INL system is its large size, leading to improved spatial and temporal resolution compared to similar facilities at smaller scales. A three-dimensional (3-D) Particle Image Velocimetry (PIV) system was used to collect the data. Inlet jet Reynolds numbers (based on the jet diameter and the time-mean average flow rate) are approximately 4,300 and 12,400. Uncertainty analysis and a discussion of the standard problem are included. The measurements reveal undeveloped, non-uniform, turbulent flow in the inlet jets and complicated flow patterns in the model lower plenum. Data include three-dimensional vector plots, data displays along the coordinate planes (slices) and presentations that describe the component flows at specific regions in the model. Information on inlet conditions are also presented.

  5. Measurement of Turbulent Flow Phenomena for the Lower Plenum of a Prismatic Gas-Cooled Reactor

    SciTech Connect

    Hugh M. McIlroy, Jr.; Donald M. McEligot; Robert J. Pink

    2010-02-01

    Mean velocity field and turbulence data are presented that measure turbulent flow phenomena in an approximately 1:7 scale model of a region of the lower plenum of a typical prismatic gas-cooled reactor (GCR) similar to a General Atomics design (Gas-Turbine-Modular Helium Reactor). The datawere obtained in the Matched-Index-of-Refraction (MIR) facility at Idaho National Laboratory (INL) and are offered as a benchmark for assessing computational fluid dynamics (CFD) software. This experiment has been selected as the first Standard Problem endorsed by the Generation IV International Forum. The primary objective of this paper is to document the experiment and present a sample of the data set that has been established for this standard problem. Present results concentrate on the region of the lower plenum near its far reflector wall (away from the outlet duct). The flowin the lower plenum consists of multiple jets injected into a confined crossflow—with obstructions. The model consists of a row of full circular posts along its centerline with half-posts on the two parallel walls to approximate flow scaled to that expected from the staggered parallel rows of posts in the reactor design. Posts, side walls and end walls are fabricated from clear, fused quartz to match the refractive index of the mineral oil working fluid so that optical techniques may be employed for the measurements. The benefit of the MIR technique is that it permits optical measurements to determine flow characteristics in complex passages and around objects to be obtained without locating intrusive transducers that will disturb the flow field and without distortion of the optical paths. An advantage of the INL system is its large size, leading to improved spatial and temporal resolution compared to similar facilities at smaller scales. A three-dimensional (3D) particle image velocimetry (PIV) system was used to collect the data. Inlet-jet Reynolds numbers (based on the hydraulic diameter of the jet and the timemean average flow rate) are approximately 4300 and 12,400. Uncertainty analysis and a discussion of the standard problem are included. The measurements reveal complicated flow patterns that include several large recirculation zones, reverse flow near the simulated reflector wall, recirculation zones in the upper portion of the plenum and complex flow patterns around the support posts. Data include three-dimensional PIV images of flow planes, data displays along the coordinate planes (slices) and presentations that describe the component flows at specific regions in the model.

  6. Measurement of Turbulent Flow Phenomena for the Lower Plenum of a Prismatic Gas-Cooled Reactor

    SciTech Connect

    Hugh M. McIlroy Jr.; Donald M. McEligot; Robert J. Pink; Keith G. Condie; Glenn E. McCreery

    2007-09-01

    Mean velocity field and turbulence data are presented for flow phenomena in a lower plenum of a typical prismatic gas-cooled reactor (GCR), such as in a Very High Temperature Reactor (VHTR) concept. In preparation for design, safety analyses and licensing, research has begun on readying the computational tools that will be needed to predict the thermal-hydraulics behavior of the reactor design. Fluid dynamics experiments have been designed and built to develop benchmark databases for the assessment of computational fluid dynamics (CFD) codes and their turbulence models for a typical VHTR plenum geometry in the limiting case of negligible buoyancy and constant fluid properties. This experiment has been proposed as a “Standard Problem” for assessing advanced reactor (CFD) analysis tools. Present results concentrate on the region of the plenum near its far reflector wall (away from the outlet duct). The flow in the lower plenum can locally be considered as multiple jets into a confined cross flow - with obstructions. A model of the lower plenum has been fabricated and scaled to the geometric dimensions of the Next Generation Nuclear Plant (NGNP) Point Design. The model consists of a row of full circular posts along its centerline with half-posts on the two parallel walls to induce flow features somewhat comparable to those expected from the staggered parallel rows of posts in the reactor design. Posts, side walls and end walls are fabricated from clear, fused quartz to match the refractive-index of the working fluid so that optical techniques may be employed for the measurements. The experiments were conducted in the Matched-Index-of-Refraction (MIR) Facility at the Idaho National Laboratory (INL). The benefit of the MIR technique is that it permits optical measurements to determine complex flow characteristics in passages and around objects to be obtained without locating a disturbing transducer in the flow field and without distortion of the optical paths. The innovative advantage of the INL system is its large size, leading to improved spatial and temporal resolution compared to others. Light mineral oil is used as the working fluid. For the data reported a 3-D Particle Image Velocimetry (PIV) system is used. The measurements reveal complicated flow patterns that include several large recirculation areas, reverse flow near the simulated reflector wall, recirculation areas in the upper portion of the plenum and complex flow patterns around the support posts. Data that will be presented include three-dimensional PIV images of flow planes, data displays along the three coordinate planes (slices) and presentations that describe the component flows at specific regions in the model.

  7. MICRO-METER MEASUREMENT OF CRACKS TO COMPARE BLAST AND ENVIRONMENTAL EFFECTS.

    E-print Network

    to development of a new approach to vibration monitoring called autonomous crack measurement (ACM Monitor Micrometer Crack Gage(s) Long-term and Vibration Displacement Neighbors/Owners/ Regulators Server Autonomously Produces WWW Graphical Comparison Figure 1 AUTONOMOUS CRACK MEASUREMENT Automatically produces

  8. Precision measurement of the proton electric to magnetic form factor ratio with BLAST

    E-print Network

    Crawford, Christopher Blair

    2005-01-01

    We have measured ... in the South Hall Ring of the MIT-Bates Linear Accelerator Facility. This experiment used a polarized electron beam, a pure hydrogen internal polarized target, and the symmetric Bates Large Acceptance ...

  9. A geophysical shock and air blast simulator at the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Fournier, K. B.; Brown, C. G.; May, M. J.; Compton, S.; Walton, O. R.; Shingleton, N.; Kane, J. O.; Holtmeier, G.; Loey, H.; Mirkarimi, P. B.; Dunlop, W. H.; Guyton, R. L.; Huffman, E.

    2014-09-01

    The energy partitioning energy coupling experiments at the National Ignition Facility (NIF) have been designed to measure simultaneously the coupling of energy from a laser-driven target into both ground shock and air blast overpressure to nearby media. The source target for the experiment is positioned at a known height above the ground-surface simulant and is heated by four beams from the NIF. The resulting target energy density and specific energy are equal to those of a low-yield nuclear device. The ground-shock stress waves and atmospheric overpressure waveforms that result in our test system are hydrodynamically scaled analogs of full-scale seismic and air blast phenomena. This report summarizes the development of the platform, the simulations, and calculations that underpin the physics measurements that are being made, and finally the data that were measured. Agreement between the data and simulation of the order of a factor of two to three is seen for air blast quantities such as peak overpressure. Historical underground test data for seismic phenomena measured sensor displacements; we measure the stresses generated in our ground-surrogate medium. We find factors-of-a-few agreement between our measured peak stresses and predictions with modern geophysical computer codes.

  10. A geophysical shock and air blast simulator at the National Ignition Facility.

    PubMed

    Fournier, K B; Brown, C G; May, M J; Compton, S; Walton, O R; Shingleton, N; Kane, J O; Holtmeier, G; Loey, H; Mirkarimi, P B; Dunlop, W H; Guyton, R L; Huffman, E

    2014-09-01

    The energy partitioning energy coupling experiments at the National Ignition Facility (NIF) have been designed to measure simultaneously the coupling of energy from a laser-driven target into both ground shock and air blast overpressure to nearby media. The source target for the experiment is positioned at a known height above the ground-surface simulant and is heated by four beams from the NIF. The resulting target energy density and specific energy are equal to those of a low-yield nuclear device. The ground-shock stress waves and atmospheric overpressure waveforms that result in our test system are hydrodynamically scaled analogs of full-scale seismic and air blast phenomena. This report summarizes the development of the platform, the simulations, and calculations that underpin the physics measurements that are being made, and finally the data that were measured. Agreement between the data and simulation of the order of a factor of two to three is seen for air blast quantities such as peak overpressure. Historical underground test data for seismic phenomena measured sensor displacements; we measure the stresses generated in our ground-surrogate medium. We find factors-of-a-few agreement between our measured peak stresses and predictions with modern geophysical computer codes. PMID:25273784

  11. Automated Blast Cleaner

    NASA Technical Reports Server (NTRS)

    Pickett, Isaiah R.; Yulfo, Alyce R.

    1992-01-01

    Automatic grit-blasting machine removes melted-layer residue from electrical-discharge-machined surfaces of turbine blades. Automatic control system of machine provides steady flow of grit and maintains blast nozzles at proper distance and in correct orientation perpendicular to surface being blasted, regardless of contour. Eliminates localized excessive blasting and consequent excessive removal of underlying material, blasting of adjacent surfaces, and missed areas.

  12. RESEARCH PAPERS : Ionospheric signature of surface mine blasts from Global Positioning System measurements

    Microsoft Academic Search

    Eric Calais; J. Bernard Minster; Michelle Hofton; Michael Hedlin

    1998-01-01

    Sources such as atmospheric or buried explosions and shallow earthquakes are known to produce infrasonic pressure waves in the atmosphere Because of the coupling between neutral particles and electrons at ionospheric altitudes, these acoustic and gravity waves induce variations of the ionospheric electron density. The Global Positioning System (GPS) provides a way of directly measuring the total electron content in

  13. Measurement of tensor analyzing powers in elastic electron deuteron scattering with BLAST

    E-print Network

    Zhang, Chi, Ph. D. Massachusetts Institute of Technology

    2006-01-01

    This work reports a precision measurement of deuteron tensor analyzing powers T20 and T21 at the MIT-Bates Linear Accelerator Center. Data were collected simultaneously over a momentum transfer range of 2:15 to 4:5 fm¡1 ...

  14. Is a Simple Measurement Task a Roadblock to Student Understanding of Wave Phenomena?

    ERIC Educational Resources Information Center

    Kryjevskaia, Mila; Stetzer, MacKenzie R.; Heron, Paula R. L

    2012-01-01

    We present results from our ongoing investigation of student understanding of periodic waves and interference phenomena at the introductory physics level. We have found that many students experience significant difficulties when they attempt to express a distance of interest in terms of the wavelength of a periodic wave. We argue that for these…

  15. Quantitative sensory testing in measurement of neuropathic pain phenomena and other sensory abnormalities.

    PubMed

    Backonja, Miroslav-Misha; Walk, David; Edwards, Robert R; Sehgal, Nalini; Moeller-Bertram, Toby; Wasan, Ajay; Irving, Gordon; Argoff, Charles; Wallace, Mark

    2009-09-01

    Neuropathic pain disorders are usually characterized by spontaneous ongoing or intermittent symptoms, stimulus-evoked positive sensory phenomena, and negative sensory phenomena. Spontaneous individual subject specific phenomena are identified in the neurologic history and are quantifiable by means of self-reported neuropathic pain symptoms tools such as scales, inventories, and questionnaires. Negative and positive sensory phenomena are assessed by the neurologic bedside examination and quantitative sensory testing (QST), which refers to psychophysical tests of sensory perception during the administration of stimuli with predetermined physical properties and following specific protocols. QST is able to capture and quantify stimulus-evoked negative and positive sensory phenomena, and as such should become standard if not a critical tool in neuropathic pain research and practice. Although the advent of anatomic and functional imaging modalities is revolutionizing our understanding of the mechanisms of neuropathic pain, only by anchoring such test results to individual subjects' own perceptions via QST can they provide meaningful information about neuropathic pain, which is based on perceptual experience. To yield useful results, QST requires a cooperative subject and carefully standardized methods, including standardization of the stimulus parameters as well as the testing environment, instructions, and evaluation methods. This manuscript provides a concise review of fundamental concepts necessary for understanding the role of QST in the process of eliciting information about sensory abnormalities associated with neuropathic pain and the place of that information in analysis of pain mechanisms. Together with the companion manuscript, this review provides definitions that should help further the use of QST as a diagnostic tool as well. PMID:19692807

  16. PROTECTIVE DESIGNS FOR BLAST AND IMPACT THREATS

    Microsoft Academic Search

    J. E. Crawford

    This paper describes methods for designing and implementing protective technologies for improving the blast and impact resistance of buildings. A protection plan for buildings may include designing blast-resistant columns, walls, and windows; other elements of security may also play a major part, including physical security measures such as: anti-ram barriers and fencing to demarcate a protective perimeter; features such as

  17. Membrane characteristics for biological blast overpressure testing using blast simulators.

    PubMed

    Alphonse, Vanessa D; Siva Sai Sujith Sajja, Venkata; Kemper, Andrew R; Rizel, Dave V; Duma, Stefan M; VandeVord, Pamela J

    2014-01-01

    Blast simulators often use passive-rupture membranes to generate shock waves similar to free-field blasts. The purpose of this study was to compare rupture patterns and pressure traces of three distinct membrane materials for biological and biomechanical blast studies. An Advanced Blast Simulator (ABS) located at the Center for Injury Biomechanics at Virginia Tech was used to test membrane characteristics. Acetate, Mylar, and aluminum sheets with different thicknesses were used to obtain pressures between 70?210 kPa. Static pressure was measured inside the tube at the test section using piezoelectric pressure sensors. Peak overpressure, positive duration, and positive impulse were calculated for each test. Rupture patterns and characteristic pressure traces were unique to each membrane type and thickness. Shock wave speed ranged between 1.2-1.8 Mach for static overpressures of 70?210 kPa. Acetate membranes fragmented sending pieces down the tube, but produced ideal (Friedlander) pressure traces. Mylar membranes bulged without fragmenting, but produced less-than-ideal pressure traces. Aluminum membranes did not fragment and produced ideal pressure traces. However, the cost of manufacturing and characterizing aluminum membranes should be considered during membrane selection. This study illustrates the advantages and disadvantages of using Mylar, acetate, and aluminum for passive rupture membranes for blast simulators. PMID:25405432

  18. Paranormal phenomena

    NASA Astrophysics Data System (ADS)

    Gaina, Alex

    1996-08-01

    Critical analysis is given of some paranormal phenomena events (UFO, healers, psychokinesis (telekinesis))reported in Moldova. It is argued that correct analysis of paranormal phenomena should be made in the framework of electromagnetism.

  19. Basic evaluation of separator type specific phenomena of polymer electrolyte membrane fuel cell by the measurement of water condensation characteristics and current density distribution

    Microsoft Academic Search

    Yutaka Tabe; Kazushige Kikuta; Takemi Chikahisa; Masaya Kozakai

    2009-01-01

    This paper investigates phenomena related to water condensation behavior inside a polymer electrolyte membrane fuel cell (PEMFC), and analyzes the effects of liquid water and gas flow on the performance of the fuel cell. A method for simultaneous measurements of the local current density across the reaction area and direct observation of the phenomena in the cell are developed. Experimental

  20. Blast investigation by fast multispectral radiometric analysis

    NASA Astrophysics Data System (ADS)

    Devir, A. D.; Bushlin, Y.; Mendelewicz, I.; Lessin, A. B.; Engel, M.

    2011-06-01

    Knowledge regarding the processes involved in blasts and detonations is required in various applications, e.g. missile interception, blasts of high-explosive materials, final ballistics and IED identification. Blasts release large amount of energy in short time duration. Some part of this energy is released as intense radiation in the optical spectral bands. This paper proposes to measure the blast radiation by a fast multispectral radiometer. The measurement is made, simultaneously, in appropriately chosen spectral bands. These spectral bands provide extensive information on the physical and chemical processes that govern the blast through the time-dependence of the molecular and aerosol contributions to the detonation products. Multi-spectral blast measurements are performed in the visible, SWIR and MWIR spectral bands. Analysis of the cross-correlation between the measured multi-spectral signals gives the time dependence of the temperature, aerosol and gas composition of the blast. Farther analysis of the development of these quantities in time may indicate on the order of the detonation and amount and type of explosive materials. Examples of analysis of measured explosions are presented to demonstrate the power of the suggested fast multispectral radiometric analysis approach.

  1. Structural blast design

    E-print Network

    Kieval, Tamar S. (Tamar Shoshana), 1980-

    2004-01-01

    Blast design is a necessary part of design for more buildings in the United States. Blast design is no longer limited to underground shelters and sensitive military sites, buildings used by the general public daily must ...

  2. Noise and blast

    NASA Technical Reports Server (NTRS)

    Hodge, D. C.; Garinther, G. R.

    1973-01-01

    Noise and blast environments are described, providing a definition of units and techniques of noise measurement and giving representative booster-launch and spacecraft noise data. The effects of noise on hearing sensitivity and performance are reviewed, and community response to noise exposure is discussed. Physiological, or nonauditory, effects of noise exposure are also treated, as are design criteria and methods for minimizing the noise effects of hearing sensitivity and communications. The low level sound detection and speech reception are included, along with subjective and behavioral responses to noise.

  3. Porcine Head Response to Blast

    PubMed Central

    Shridharani, Jay K.; Wood, Garrett W.; Panzer, Matthew B.; Capehart, Bruce P.; Nyein, Michelle K.; Radovitzky, Raul A.; Bass, Cameron R. ‘Dale’

    2012-01-01

    Recent studies have shown an increase in the frequency of traumatic brain injuries related to blast exposure. However, the mechanisms that cause blast neurotrauma are unknown. Blast neurotrauma research using computational models has been one method to elucidate that response of the brain in blast, and to identify possible mechanical correlates of injury. However, model validation against experimental data is required to ensure that the model output is representative of in vivo biomechanical response. This study exposes porcine subjects to primary blast overpressures generated using a compressed-gas shock tube. Shock tube blasts were directed to the unprotected head of each animal while the lungs and thorax were protected using ballistic protective vests similar to those employed in theater. The test conditions ranged from 110 to 740?kPa peak incident overpressure with scaled durations from 1.3 to 6.9?ms and correspond approximately with a 50% injury risk for brain bleeding and apnea in a ferret model scaled to porcine exposure. Instrumentation was placed on the porcine head to measure bulk acceleration, pressure at the surface of the head, and pressure inside the cranial cavity. Immediately after the blast, 5 of the 20 animals tested were apneic. Three subjects recovered without intervention within 30?s and the remaining two recovered within 8?min following respiratory assistance and administration of the respiratory stimulant doxapram. Gross examination of the brain revealed no indication of bleeding. Intracranial pressures ranged from 80 to 390?kPa as a result of the blast and were notably lower than the shock tube reflected pressures of 300–2830?kPa, indicating pressure attenuation by the skull up to a factor of 8.4. Peak head accelerations were measured from 385 to 3845 G’s and were well correlated with peak incident overpressure (R2?=?0.90). One SD corridors for the surface pressure, intracranial pressure (ICP), and head acceleration are presented to provide experimental data for computer model validation. PMID:22586417

  4. Nineteen-Foot Diameter Explosively Driven Blast Simulator

    SciTech Connect

    VIGIL,MANUEL G.

    2001-07-01

    This report describes the 19-foot diameter blast tunnel at Sandia National Laboratories. The blast tunnel configuration consists of a 6 foot diameter by 200 foot long shock tube, a 6 foot diameter to 19 foot diameter conical expansion section that is 40 feet long, and a 19 foot diameter test section that is 65 feet long. Therefore, the total blast tunnel length is 305 feet. The development of this 19-foot diameter blast tunnel is presented. The small scale research test results using 4 inch by 8 inch diameter and 2 foot by 6 foot diameter shock tube facilities are included. Analytically predicted parameters are compared to experimentally measured blast tunnel parameters in this report. The blast tunnel parameters include distance, time, static, overpressure, stagnation pressure, dynamic pressure, reflected pressure, shock Mach number, flow Mach number, shock velocity, flow velocity, impulse, flow duration, etc. Shadowgraphs of the shock wave are included for the three different size blast tunnels.

  5. Lidar and radar measurements of the melting layer: observations of dark and bright band phenomena

    NASA Astrophysics Data System (ADS)

    Di Girolamo, P.; Summa, D.; Cacciani, M.; Norton, E. G.; Peters, G.; Dufournet, Y.

    2012-05-01

    Multi-wavelength lidar measurements in the melting layer revealing the presence of dark and bright bands have been performed by the University of BASILicata Raman lidar system (BASIL) during a stratiform rain event. Simultaneously radar measurements have been also performed from the same site by the University of Hamburg cloud radar MIRA 36 (35.5 GHz), the University of Hamburg dual-polarization micro rain radar (24.15 GHz) and the University of Manchester UHF wind profiler (1.29 GHz). Measurements from BASIL and the radars are illustrated and discussed in this paper for a specific case study on 23 July 2007 during the Convective and Orographically-induced Precipitation Study (COPS). Simulations of the lidar dark and bright band based on the application of concentric/eccentric sphere Lorentz-Mie codes and a melting layer model are also provided. Lidar and radar measurements and model results are also compared with measurements from a disdrometer on ground and a two-dimensional cloud (2DC) probe on-board the ATR42 SAFIRE. Measurements and model results are found to confirm and support the conceptual microphysical/scattering model elaborated by Sassen et al. (2005).

  6. Porcine head response to blast

    E-print Network

    Nyein, Michelle K.

    Recent studies have shown an increase in the frequency of traumatic brain injuries related to blast exposure. However, the mechanisms that cause blast neurotrauma are unknown. Blast neurotrauma research using computational ...

  7. Solvent swelling of Coal 1. Development of an improved method for measuring swelling phenomena

    Microsoft Academic Search

    T. Aida; T. G. Squires

    1985-01-01

    The swelling induced by contracting coal with organic solvents has been investigated intensively in recent years; and several convenient methods using both liquids and saturated vapors have been developed for mesuring coal swelling properties. The liquid phase swelling behavior is particularly interesting because it is a reasonable measure of a solvent's ability to penetrate the coal matrix. Previously, investigators of

  8. The atmosphere UV background phenomena measured by detector on-board ``Tatiana'' satellite

    NASA Astrophysics Data System (ADS)

    Klimov, P. A.; Garipov, G. K.; Khrenov, B. A.; et al.

    Near UV detector on-board the “Universitetsky-Tatiana” satellite has observed the atmosphere glow at night side of the Earth. Digital oscilloscopes help to select transient luminous events and to measure their temporal profiles in time scale of 1-64 ms. Data from those detectors were analyzed for prediction the duty cycle of future space detectors of ultra high energy cosmic rays.

  9. Rotating Molten Metallic Drops and Related Phenomena: A New Approach to the Surface Tension Measurement

    NASA Technical Reports Server (NTRS)

    Rhim, Won-Kyu; Ishikawa, Takehiko

    2000-01-01

    Molten aluminum and tin drops were levitated in a high vacuum by controlled electric fields, and they were systematically rotated by applying by a rotating magnetic field. When the evolution of the drop shape was measured as a function of rotation frequency, it agreed quantitatively well with the Brown and Scriven's theoretical prediction. The normalized rotation frequencies at the bifurcation point agreed with the predicted value 0.559, within 2%. An anomalous phenomenon which totally deviated from the prediction was observed in rotating molten tin drops when they were kept in a high rotation rate for several hours. No anomaly was observed in aluminum drops when they underwent similar condition. It was speculated that under the strong centrifugal force in the drop the tin isotopes must be separating. Since Al-27 is essentially the only naturally abundant isotope in the aluminum drops, the same anomaly is not expected. Based on the shape deformation of a rotating drop, an alternate approach to the surface tension measurement was verified. This new surface tension measurement technique was applied to a glassforming alloy, Zr(41.2)Ti(13.8)Cu(12.5)Ni(10.0)Be(22.5) in its highly viscous states. Also demonstrated in the paper was a use of a molten aluminum drop to verify the Busse's prediction of the influence of the drop rotation on the drop oscillation frequency.

  10. Material Systems for Blast-Energy Dissipation

    SciTech Connect

    James Schondel; Henry S. Chu

    2010-10-01

    Lightweight panels have been designed to protect buildings and vehicles from blast pressures by activating energy dissipation mechanisms under the influence of blast loading. Panels were fabricated which featured a variety of granular materials and hydraulic dissipative deformation mechanisms and the test articles were subjected to full-scale blast loading. The force time-histories transmitted by each technology were measured by a novel method that utilized inexpensive custom-designed force sensors. The array of tests revealed that granular materials can effectively dissipate blast energy if they are employed in a way that they easily crush and rearrange. Similarly, hydraulic dissipation can effectively dissipate energy if the panel features a high fraction of porosity and the panel encasement features low compressive stiffness.

  11. A Superradiant Laser and Spin Squeezed States: Collective Phenomena in a Rubidium Cavity QED System for Enhancing Precision Measurements

    NASA Astrophysics Data System (ADS)

    Bohnet, Justin G.

    By allowing a large ensemble of laser cooled and trapped 87Rb atoms to interact collectively with an optical cavity, I have explored two phenomena that may prove useful for enhancing precision measurements: superradiant lasing and spin squeezing. Superradiant lasers have been proposed as future ultrastable optical frequency references, with predicted linewidths < 1 millihertz. These lasers operate in an unusual regime of laser physics where collective emission from an atomic ensemble maps the quantum phase stored in the atoms onto the optical cavity field. I will give an overview of my experimental work using a cold-atom, superradiant Raman laser as a model system to confirm a number of the key predictions concerning superradiant lasing, including the possibility of coherent emission with < 1 intracavity photon on average and greatly reduced sensitivity to cavity frequency noise. I also present work using cavity-aided, coherence-preserving measurements of the atomic state population to create entanglement between atoms. The entanglement enables more precise estimation of the quantum phase at the heart of nearly all precision measurements and sensors utilizing quantum objects. By utilizing a cycling transition for the quantum non-demolition probe, we have reduced by several orders of magnitude the measurement induced back-action caused by spontaneous Raman transitions. We directly observe, with no background subtraction, a spin squeezed state with sensitivity to measuring a quantum phase enhanced 10.5 times in variance (i.e. 10.2 dB) beyond the standard quantum limit for an unentangled state. This experimental breakthrough demonstrates that quantum-aided sensing techniques can realize large enough enhancements to have a substantial impact on precision measurements and may aid advances in technology as well as searches for new physics.

  12. Characterization of Side Load Phenomena Using Measurement of Fluid/Structure Interaction

    NASA Technical Reports Server (NTRS)

    Brown, Andrew M.; Ruf, Joseph; Reed, Darren; DAgostino, Mark; Keanini, Russell; McConnaughey, Paul K. (Technical Monitor)

    2002-01-01

    During ground-tests of most production rocket engines over the last 30 years, large asymmetric transient side loads coming from the nozzle and related steady-state vibrational loads within the nozzle have been measured. The widely varying magnitude of these loads has been large enough to fail interfacing components as well as nozzles in these engines. This paper will discuss a comprehensive test and analysis program that has been undertaken to develop a methodology to accurately predict the character and magnitude of this loading. The project to-date has incorporated analytical modeling of both the fluid flow and the nozzle structure and testing of both full-scale and sub-scale rocket nodes. Examination of the test data indicates that one of the two-nodal diameter structural modes may be interacting with flow separation from the nozzle inside-wall in a self-excited or aeroelastic vibration phenomenon. If verified, this observation will be used to develop a methodology for design and analysis. A fuller understanding of the characteristics of this vibration will provide an increase in the accuracy and confidence of side load predictions, which will be critical for the successful construction of the next generation of low-cost, reliable rocket engines.

  13. Lightweight blast shield

    DOEpatents

    Mixon, Larry C. (Madison, AL); Snyder, George W. (Huntsville, AL); Hill, Scott D. (Toney, AL); Johnson, Gregory L. (Decatur, AL); Wlodarski, J. Frank (Huntsville, AL); von Spakovsky, Alexis P. (Huntsville, AL); Emerson, John D. (Arab, AL); Cole, James M. (Huntsville, AL); Tipton, John P. (Huntsville, AL)

    1991-01-01

    A tandem warhead missile arrangement that has a composite material housing structure with a first warhead mounted at one end and a second warhead mounted near another end of the composite structure with a dome shaped composite material blast shield mounted between the warheads to protect the second warhead from the blast of the first warhead.

  14. Robotic Water Blast Cleaner

    NASA Technical Reports Server (NTRS)

    Sharpe, M. H.; Roberts, M. L.; Hill, W. E.; Jackson, C. H.

    1983-01-01

    Water blasting system under development removes hard, dense, extraneous material from surfaces. High pressure pump forces water at supersonic speed through nozzle manipulated by robot. Impact of water blasts away unwanted material from workpiece rotated on air bearing turntable. Designed for removing thermal-protection material, system is adaptable to such industrial processes as cleaning iron or steel castings.

  15. Resonant phenomena of circumferential Lamb waves by eight transducer elements located evenly on girth and wall thickness measurements

    NASA Astrophysics Data System (ADS)

    Nishino, Hideo; Morita, Keiichi

    2014-02-01

    The purpose of this paper is to present a newly developed method for measuring a wall thickness using the resonance of the circumferential (C-) Lamb wave. In this method, a piezoelectric ring-shaped sensor (PeRS used normally for the torsional guided waves propagating along the axial directions) is used for the transduction of the C-Lamb waves. The PeRS used in the experiments has the eight transducer elements located evenly on the girth for the guided wave generations. Because the transducer elements vibrate circumferential directions, the axial torsional guided waves and the C-Lamb waves are generated simultaneously. The C-Lamb waves are usually spurious signals for the axial guided wave inspections; however, in the method, the resonant phenomena of the C-Lamb waves are utilized for the wall thickness estimations. It was shown that the measurement of the resonant frequency enabled the wall thickness estimation. The experimental verifications of the principle were also shown. The results showed that the experimental estimations of wall thicknesses agreed excellently with the theoretical predictions.

  16. Effect of Meteorological Phenomena in Measures of Background Radiation X and Gamma Rays in São José dos Campos, SP, Brazil

    NASA Astrophysics Data System (ADS)

    Gomes, Marcelo; Spjeldvik, Walther; Gusev, Anatoly; Alves, Mauro; Martin, Inacio; Pinto, Marcos; Ferro, Marco A.; Concei, Flavio

    The objective of this work was to perform a study on the influence of meteorological phenomena on the background radiation X and gamma rays in São José dos Campos, SP, Brazil on the last three years. For this, we performed the monitoring of the integrated radiations and also of the main meteorological parameters (rainfall, relative humidity, temperature and pressure) daily without interruptions and time resolution of one minute. Measurements of X and gamma radiation in the range of energies from 30 keV to 10 MeV, were carried out using a scintillator crystal of sodium iodide activated with Tallium [NaI(Tl)] coupled to a photomultiplier, with energy resolution of 15%. Rainfall, atmospheric pressure, temperature, and relative humidity were recorded using sensors coupled to a five-channel specific data logger. By correlating the data from the measurements of intensity of X and gamma radiations with the meteorological parameters, it was found that atmospheric precipitation with or without electric discharges phenomenon that was affected more in the spectrum of background radiation profile. Some of the reasons why these changes occur in the background profile are due the presence of environmental radon gas that is drawn to the surface during the occurrences of local rainfall. During dry periods, the spectra of X and gamma radiations showed a daily cycle (24 hour). In relation to relative humidity, temperature and pressure, it was found that these parameters had negligible influence on the profile changes of the background radiation in São José dos Campos, SP, Brazil.

  17. On the Interaction and Coalescence if Spherical Blast Waves

    NASA Technical Reports Server (NTRS)

    Kandula, Max; Freeman, Robert J.

    2005-01-01

    The scaling and similarity laws concerning the propagation of isolated spherical blast waves are briefly reviewed. Both point source explosions and high pressure gas explosions are considered. Test data on blast overpressure from the interaction and coalescence of spherical blast waves emanating from explosives in the form of shaped charges of different strength placed in the vicinity of a solid propellant stack are presented. These data are discussed with regard to the scaling laws concerning the decay of blast overpressure. The results point out the possibility of detecting source explosions from far-field pressure measurements.

  18. A 3D CFD simulation of liquid flow in an ironmaking blast furnace

    NASA Astrophysics Data System (ADS)

    Shen, Yansong; Guo, Baoyu; Chew, Sheng; Austin, Peter; Yu, Aibing

    2013-07-01

    A three-dimensional CFX-based mathematical model is developed to describe the flow-heat transfer-chemical reactions behaviours of gas-solid-liquid phases in an ironmaking blast furnace (BF), where the raceway cavity is considered explicitly. The typical in-furnace phenomena of an operating blast furnace, in particular, the liquid flow in the lower part of a blast furnace is simulated in aspects of velocity and volume fraction. This model offers a cost-effective tool to understand and optimize blast furnace operation.

  19. Effects of mine blasting on residential structures

    SciTech Connect

    Gad, E.F.; Wilson, J.L.; Moore, A.J.; Richards, A.B. [Swinburne University of Technology, Hawthorn, Vic. (Australia). Faculty of Engineering & Industrial Science

    2005-08-01

    Blasting is common in the coal industry to remove rock overburden so that the exposed coal can be mechanically excavated. The ground vibrations and air blast produced by blasting are often felt by residents surrounding the mines. There has been a trend for regulatory authorities, especially those concerned with the environment, to impose low limits on blast vibration levels in response to community pressure, based on human perception and response to vibration. This paper reports the findings of an extensive study on a house which was located adjacent to a coal mine. The house was monitored for over 1 year and was subjected to ground peak particle velocity (PPV) ranging from 1.5 to 222 mm/s. The house was instrumented with accelerometers to measure its dynamic response due to blasting and it was also monitored for cracks before and after each blast. Based on this study, ground motion amplifications along the height of the structure have been established. A simplified methodology presented in this paper has been used to estimate the ground PPV at which cracking is likely.

  20. Light flavor hadron spectra at low pT and search for collective phenomena in high multiplicity pp, p-Pb and Pb-Pb collisions measured with the ALICE experiment

    NASA Astrophysics Data System (ADS)

    Andrei, C.

    2014-11-01

    Comprehensive results on transverse momentum distributions and their ratios for identified light flavor hadrons (?, K, p) at low pT and mid-rapidity as a function of charged particle multiplicity are reported for pp collisions at 7 TeV. Particle mass dependent hardening of the spectral shapes in Pb-Pb collisions at 2.76 TeV were attributed to hydrodynamical flow and quantitatively parameterized with Boltzmann-Gibbs Blast Wave fits. In this contribution, we investigate the existence of collective phenomena in small systems: pp, p-Pb and peripheral Pb-Pb where similar patterns are observed in multiplicity dependent studies.

  1. Transport Phenomena.

    ERIC Educational Resources Information Center

    McCready, Mark J.; Leighton, David T.

    1987-01-01

    Discusses the problems created in graduate chemical engineering programs when students enter with a wide diversity of understandings of transport phenomena. Describes a two-semester graduate transport course sequence at the University of Notre Dame which focuses on fluid mechanics and heat and mass transfer. (TW)

  2. Evolution of blast wave profiles in simulated air blasts: experiment and computational modeling

    NASA Astrophysics Data System (ADS)

    Chandra, N.; Ganpule, S.; Kleinschmit, N. N.; Feng, R.; Holmberg, A. D.; Sundaramurthy, A.; Selvan, V.; Alai, A.

    2012-09-01

    Shock tubes have been extensively used in the study of blast traumatic brain injury due to increased incidence of blast-induced neurotrauma in Iraq and Afghanistan conflicts. One of the important aspects in these studies is how to best replicate the field conditions in the laboratory which relies on reproducing blast wave profiles. Evolution of the blast wave profiles along the length of the compression-driven air shock tube is studied using experiments and numerical simulations with emphasis on the shape and magnitude of pressure time profiles. In order to measure dynamic pressures of the blast, a series of sensors are mounted on a cylindrical specimen normal to the flow direction. Our results indicate that the blast wave loading is significantly different for locations inside and outside of the shock tube. Pressure profiles inside the shock tube follow the Friedlander waveform fairly well. Upon approaching exit of the shock tube, an expansion wave released from the shock tube edges significantly degrades the pressure profiles. For tests outside the shock tube, peak pressure and total impulse reduce drastically as we move away from the exit and majority of loading is in the form of subsonic jet wind. In addition, the planarity of the blast wave degrades as blast wave evolves three dimensionally. Numerical results visually and quantitatively confirm the presence of vortices, jet wind and three-dimensional expansion of the planar blast wave near the exit. Pressure profiles at 90° orientation show flow separation. When cylinder is placed inside, this flow separation is not sustained, but when placed outside the shock tube this flow separation is sustained which causes tensile loading on the sides of the cylinder. Friedlander waves formed due to field explosives in the intermediate-to far-field ranges are replicated in a narrow test region located deep inside the shock tube.

  3. Joint geophysical measurements to investigate the Rossano of Vaglio archaeological site affected by landslide phenomena (Basilicata region, Southern Italy)

    NASA Astrophysics Data System (ADS)

    Perrone, A.; Chianese, D.; Lapenna, V.; Lorenzo, P.; Piscitelli, S.; Rizzo, E.; Sdao, F.

    2003-04-01

    In the frame of a project supported by the Italian Ministry of Research: "Geomorphological study and landslides control in some areas of the Basilicata region characterized by historical-cultural heritage", the I.M.A.A. of the CNR (Tito Scalo, Potenza) and the Di.S.G.G. of the Basilicata University, developed a research activity focussed on the realization of combined geophysical measurements for the study of archaeological areas affected by landslide phenomena in Basilicata region (Southern Italy). Since IV century b.C., the birth and the evolution of many religious places is observed in the Basilicata region. Location and construction of these sanctuaries were influenced by the geological and geomorphological setting: many of them were built near important springs; others on morphological terraces, representing the main effect of the large and ancient landslides, often reactivated during the years. In this work we report the results regarding the application of 2D electrical resistivity tomographies, electromagnetic and magnetic measurements carried out in the Rossano of Vaglio (Potenza, Italy), where in the late IV century b.C. raised a sanctuary devoted to the Mephitis goddess (Adamasteanu and Dilthey, 1992; Masseria and D'Anisi, 2001). The sacred area was affected by a multiple and retrogressive rototranslational slide, historically and actually subject to reactivation. The geophysical results, obtained combining advanced technologies for data acquisition and new methods for data inversion (Loke and Barker, 1996; Ciminale and Loddo, 2001; Nuzzo et al, 2002), allowed us to define the geometrical characteristics of the landslide body, to outline the sliding surfaces and to individuate the buried structures of the sanctuary.

  4. Integrated, Multi-Scale Characterization of Imbibition and Wettability Phenomena Using Magnetic Resonance and Wide-Band Dielectric Measurements

    SciTech Connect

    Mukul M. Sharma; Steven L. Bryant; Carlos Torres-Verdin; George Hirasaki

    2007-09-30

    The petrophysical properties of rocks, particularly their relative permeability and wettability, strongly influence the efficiency and the time-scale of all hydrocarbon recovery processes. However, the quantitative relationships needed to account for the influence of wettability and pore structure on multi-phase flow are not yet available, largely due to the complexity of the phenomena controlling wettability and the difficulty of characterizing rock properties at the relevant length scales. This project brings together several advanced technologies to characterize pore structure and wettability. Grain-scale models are developed that help to better interpret the electric and dielectric response of rocks. These studies allow the computation of realistic configurations of two immiscible fluids as a function of wettability and geologic characteristics. These fluid configurations form a basis for predicting and explaining macroscopic behavior, including the relationship between relative permeability, wettability and laboratory and wireline log measurements of NMR and dielectric response. Dielectric and NMR measurements have been made show that the response of the rocks depends on the wetting and flow properties of the rock. The theoretical models can be used for a better interpretation and inversion of standard well logs to obtain accurate and reliable estimates of fluid saturation and of their producibility. The ultimate benefit of this combined theoretical/empirical approach for reservoir characterization is that rather than reproducing the behavior of any particular sample or set of samples, it can explain and predict trends in behavior that can be applied at a range of length scales, including correlation with wireline logs, seismic, and geologic units and strata. This approach can substantially enhance wireline log interpretation for reservoir characterization and provide better descriptions, at several scales, of crucial reservoir flow properties that govern oil recovery.

  5. Removal of phosphate from aqueous solution with blast furnace slag

    Microsoft Academic Search

    Ensar Oguz

    2004-01-01

    Blast furnace slag was used to remove phosphate from aqueous solutions. The influence of pH, temperature, agitation rate, and blast furnace slag dosage on phosphate removal was investigated by conducting a series of batch adsorption experiments. In addition, the yield and mechanisms of phosphate removal were explained on the basis of the results of X-ray spectroscopy, measurements of zeta potential

  6. Operation Greenhouse. Scientific Director's report of atomic-weapon tests at Eniwetok, 1951. Annex 1. 6. Blast measurements. Part 2. Free-air peak-pressure measurements. Section 2. Telemetering from moored balloons

    SciTech Connect

    Frolich, A.J.

    1985-09-01

    The purpose of this experiment was to determine the free-air peak-pressure as a function of distance from an atomic explosion. In this report, free-air peak-pressure is defined as the pressure at the head of the blast wave in regions where it has not been reinforced by a reflected wave. Operation in the test area was more difficult than anticipated. Heavy winds made balloon handling very difficult. On the whole, the radio link performed satisfactorily on all occasions and appears to be a reliable method. For some unknown reason, blast switches closer than 1,500 feet failed to give satisfactory signals. Pressures were computed using the Rankine-Hugoniot relation, which is based on the shock wave being a definite discontinuity in pressure. Since the pressures measured on the ground showed relatively long times, there has been some speculation that a true shock wave may not exist in free air. If a true shock wave does not exist in the free-air region, pressures as computed are not correct, and the method of this experiment cannot be used.

  7. ESF BLAST DESIGN ANALYSIS

    SciTech Connect

    E.F. fitch

    1995-03-13

    The purpose and objective of this design analysis are to develop controls considered necessary and sufficient to implement the requirements for the controlled drilling and blasting excavation of operations support alcoves and test support alcoves in the Exploratory Studies Facility (ESF). The conclusions reached in this analysis will flow down into a construction specification ensuring controlled drilling and blasting excavation will be performed within the bounds established here.

  8. Development Of An Experiment For Measuring Flow Phenomena Occurring In A Lower Plenum For VHTR CFD Assessment

    SciTech Connect

    D. M. McEligot; K.G. Condie; G. E. Mc Creery; H. M. Mc Ilroy

    2005-09-01

    The objective of the present report is to document the design of our first experiment to measure generic flow phenomena expected to occur in the lower plenum of a typical prismatic VHTR (Very High Temperature Reactor) concept. In the process, fabrication sketches are provided for the use of CFD (computational fluid dynamics) analysts wishing to employ the data for assessment of their proposed codes. The general approach of the project is to develop new benchmark experiments for assessment in parallel with CFD and coupled CFD/systems code calculations for the same geometry. One aspect of the complex flow in a prismatic VHTR is being addressed: flow and thermal mixing in the lower plenum ("hot streaking" issue). Current prismatic VHTR concepts were examined to identify their proposed flow conditions and geometries over the range from normal operation to decay heat removal in a pressurized cooldown. Approximate analyses were applied to determine key non-dimensional parameters and their magnitudes over this operating range. The flow in the lower plenum can locally be considered to be a situation of multiple jets into a confined crossflow -- with obstructions. Flow is expected to be turbulent with momentum-dominated turbulent jets entering; buoyancy influences are estimated to be negligible in normal full power operation. Experiments are needed for the combined features of the lower plenum flows. Missing from the typical jet experiments available are interactions with nearby circular posts and with vertical posts in the vicinity of vertical walls - with near stagnant surroundings at one extreme and significant crossflow at the other.

  9. Curved characteristics behind blast waves.

    NASA Technical Reports Server (NTRS)

    Laporte, O.; Chang, T. S.

    1972-01-01

    The behavior of nonisentropic flow behind a propagating blast wave is theoretically studied. Exact solutions, expressed in closed form in terms of elementary functions, are presented for three sets of curved characteristicseind a self-similar, strong blast wave.

  10. Isothermal blast wave model of supernova remnants

    NASA Technical Reports Server (NTRS)

    Solinger, A.; Buff, J.; Rappaport, S.

    1975-01-01

    The validity of the 'adiabatic' assumption in supernova-remnant calculations is examined, and the alternative extreme of an isothermal blast wave is explored. It is concluded that, because of thermal conductivity, the large temperature gradients predicted by the adiabatic model probably are not maintained in nature. Self-similar solutions to the hydrodynamic equations for an isothermal blast wave have been found and studied. These solutions are then used to determine the relationship between X-ray observations and inferred parameters of supernova remnants. A comparison of the present results with those for the adiabatic model indicates differences which are less than present observational uncertainties. It is concluded that most parameters of supernova remnants inferred from X-ray measurements are relatively insensitive to the specifics of the blast-wave model.

  11. Cygnus Loop Supernova Blast Wave

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This is an image of a small portion of the Cygnus Loop supernova remnant, which marks the edge of a bubble-like, expanding blast wave from a colossal stellar explosion, occurring about 15,000 years ago. The HST image shows the structure behind the shock waves, allowing astronomers for the first time to directly compare the actual structure of the shock with theoretical model calculations. Besides supernova remnants, these shock models are important in understanding a wide range of astrophysical phenomena, from winds in newly-formed stars to cataclysmic stellar outbursts. The supernova blast is slamming into tenuous clouds of insterstellar gas. This collision heats and compresses the gas, causing it to glow. The shock thus acts as a searchlight revealing the structure of the interstellar medium. The detailed HST image shows the blast wave overrunning dense clumps of gas, which despite HST's high resolution, cannot be resolved. This means that the clumps of gas must be small enough to fit inside our solar system, making them relatively small structures by interstellar standards. A bluish ribbon of light stretching left to right across the picture might be a knot of gas ejected by the supernova; this interstellar 'bullet' traveling over three million miles per hour (5 million kilometres) is just catching up with the shock front, which has slowed down by ploughing into interstellar material. The Cygnus Loop appears as a faint ring of glowing gases about three degrees across (six times the diameter of the full Moon), located in the northern constellation, Cygnus the Swan. The supernova remnant is within the plane of our Milky Way galaxy and is 2,600 light-years away. The photo is a combination of separate images taken in three colors, oxygen atoms (blue) emit light at temperatures of 30,000 to 60,000 degrees Celsius (50,000 to 100,000 degrees Farenheit). Hydrogen atoms (green) arise throughout the region of shocked gas. Sulfur atoms (red) form when the gas cools to around 10,000 degrees Celsius (18,000 degrees Farenheit).

  12. Data Analysis Measurement: Having a Solar Blast! NASA Connect: Program 7 in the 2001-2002 Video Series. [Videotape].

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Hampton, VA. Langley Research Center.

    NASA Connect is an interdisciplinary, instructional distance learning program targeting students in grades 6-8. This videotape explains how engineers and researchers at the National Aeronautics and Space Administration (NASA) use data analysis and measurement to predict solar storms, anticipate how they will affect the Earth, and improve…

  13. External Resource: Having a Solar Blast

    NSDL National Science Digital Library

    1900-01-01

    In Data Analysis and Measurement: Having a Solar Blast!, students will learn how NASA researchers study the Sun. They will learn how satellite technology plays a pivotal role in helping NASA researchers understand the Sun-Earth connection. Students will l

  14. Compound 49b protects against blast-induced retinal injury

    PubMed Central

    2013-01-01

    Aim To determine whether Compound 49b, a novel beta-adrenergic receptor agonist, can prevent increased inflammation and apoptosis in mice after exposure to ocular blast. Methods Eyes of C57/BL6 mice were exposed to a blast of air from a paintball gun at 26 psi (?0.18 MPa). Eyes were collected 4 hours, 24 hours, and 72 hours after blast exposure. In a subset of mice, Compound 49b eyedrops (1 mM) were applied within 4 hours, 24 hours, or 72 hours of the blast. Three days after blast exposure, all mice were sacrificed. One eye was used to measure levels of retinal proteins (TNF?, IL-1?, Bax, BcL-xL, caspase 3, and cytochrome C). The other eye was used for TUNEL labeling of apoptotic cells, which were co-labeled with NeuN to stain for retinal ganglion cells. Results We found that ocular exposure to 26 psi air pressure led to a significant increase in levels of apoptotic and inflammatory mediators within 4 hours, which lasted throughout the period investigated. When Compound 49b was applied within 4 hours or 24 hours of blast injury, levels of apoptotic and inflammatory mediators were significantly reduced. Application of Compound 49b within 72 hours of blast injury reduced levels of inflammatory mediators, but not to untreated levels. Conclusions Ocular blast injury produces a significant increase in levels of key inflammatory and apoptotic markers in the retina as early as 4 hours after blast exposure. These levels are significantly reduced if a beta-adrenergic receptor agonist is applied within 24 hours of blast exposure. Data suggest that local application of beta-adrenergic receptor agonists may be beneficial to reduce inflammation and apoptosis. PMID:23899290

  15. Macro-mechanical modeling of blast-wave mitigation in foams. Part II: reliability of pressure measurements

    NASA Astrophysics Data System (ADS)

    Britan, A.; Liverts, M.; Shapiro, H.; Ben-Dor, G.

    2013-02-01

    A phenomenological study of the process occurring when a plane shock wave reflected off an aqueous foam column filling the test section of a vertical shock tube has been undertaken. The experiments were conducted with initial shock wave Mach numbers in the range 1.25le {M}_s le 1.7 and foam column heights in the range 100-450 mm. Miniature piezotrone circuit electronic pressure transducers were used to record the pressure histories upstream and alongside the foam column. The aim of these experiments was to find a simple way to eliminate a spatial averaging as an artifact of the pressure history recorded by the side-on transducer. For this purpose, we discuss first the common behaviors of the pressure traces in extended time scales. These observations evidently quantify the low frequency variations of the pressure field within the different flow domains of the shock tube. Thereafter, we focus on the fronts of the pressure signals, which, in turn, characterize the high-frequency response of the foam column to the shock wave impact. Since the front shape and the amplitude of the pressure signal most likely play a significant role in the foam destruction, phase changes and/or other physical factors, such as high capacity, viscosity, etc., the common practice of the data processing is revised and discussed in detail. Generally, side-on pressure measurements must be used with great caution when performed in wet aqueous foams, because the low sound speed is especially prone to this effect. Since the spatial averaged recorded pressure signals do not reproduce well the real behaviors of the pressure rise, the recorded shape of the shock wave front in the foam appears much thicker. It is also found that when a thin liquid film wet the sensing membrane, the transducer sensitivity was changed. As a result, the pressure recorded in the foam could exceed the real amplitude of the post-shock wave flow. A simple procedure, which allows correcting this imperfection, is discussed in detail.

  16. Laser-plasma simulations of astrophysical phenomena and novel applications to semiconductor annealing

    NASA Astrophysics Data System (ADS)

    Grun, J.; Laming, M.; Manka, C.; Donnelly, D. W.; Covington, B. C.; Fischer, R. P.; Velikovich, A.; Khokhlov, A.

    2003-10-01

    At the frontier of plasma physics and technology are applications of laser-generated plasmas to laboratory simulations of astrophysical phenomena and to industrial processing. This article presents work at the Naval Research Laboratory in both of these areas. We show how laser plasmas are used to measure a blast wave corrugation overstability important in astrophysics. Detailed atomic physics calculations of radiative cooling within the blast front are used to develop a criterion of the existence of the overstability and are used to explain the experimental results. The criterion depends on quantities such as element abundances, densities, temperatures, and blast wave velocities—quantities which can be measured spectroscopically—and therefore used to infer whether astrophysical blast wave nonuniformities are the result of this instability. In other experiments, high-velocity jets are formed in the laboratory using miniature hollow cones. Jets produced by these cones are used to study the physics of jets occurring in supernovae and in star-forming accretion disks. In industrial semiconductor processing, annealing, that is, removing crystal damage and electrically activating the semiconductor, is a critical step. Industrial annealing techniques most often utilize heat generated by an oven, flash lamps, or a low-power laser. During such heating dopants within the semiconductor lattice diffuse and spread. This degrades the performance of circuits in which the individual circuit elements are very close to each other. We are developing an annealing technique in which shock or sound waves generated by a laser plasma are used to anneal the semiconductor. We have demonstrated that the method works over small areas and that it does not lead to significant dopant diffusion.

  17. Pressure measurements and high speed visualizations of the cavitation phenomena at deep part load condition in a Francis turbine

    NASA Astrophysics Data System (ADS)

    Yamamoto, K.; Müller, A.; Favrel, A.; Landry, C.; Avellan, F.

    2014-12-01

    In a hydraulic power plant, it is essential to provide a reliable, sustainable and flexible energy supply. In recent years, in order to cover the variations of the renewable electricity production, hydraulic power plants are demanded to operate with more extended operating range. Under these off-design conditions, a hydraulic turbine is subject to cavitating swirl flow at the runner outlet. It is well-known that the helically/symmetrically shaped cavitation develops at the runner outlet in part load/full load condition, and it gives severe damage to the hydraulic systems under certain conditions. Although there have been many studies about partial and full load conditions, contributions reporting the deep part load condition are limited, and the cavitation behaviour at this condition is not yet understood. This study aims to unveil the cavitation phenomena at deep part load condition by high speed visualizations focusing on the draft tube cone as well as the runner blade channel, and pressure fluctuations associated with the phenomena were also investigated.

  18. Pediatric blast lung injury from a fireworks-related explosion.

    PubMed

    Ratto, Jessica; Johnson, Bernadette K; Condra, Cole S; Knapp, Jane F

    2012-06-01

    Blast injuries related to explosions have been described in the literature but are uncommon in children. We describe a multisystem blast injury in a child resulting from a commercial firework-related explosion in her home. She presented with respiratory failure, shock, altered level of consciousness, and multiple orthopedic injuries. The patient required immediate stabilization and resuscitation in the emergency department and a prolonged hospitalization. This report reviews the spectrum of injuries that are seen in blast-related trauma and the emergency measures needed for rapid stabilization of these critical patients. PMID:22668665

  19. Molecular Changes and Vision Loss in a Mouse Model of Closed-Globe Blast Trauma

    PubMed Central

    Bricker-Anthony, Courtney; Hines-Beard, Jessica; Rex, Tonia S.

    2014-01-01

    Purpose. To characterize retinal changes and assess vision after an eye-directed air blast. Methods. Adult C57Bl/6 mice were exposed to a blast directed at one eye. Optical coherence tomography and histology were performed to assess retina and optic nerve integrity. Cell death, oxidative stress, and glial reactivity were examined by immunohistochemistry. Visual changes were measured by ERG recordings and the optokinetic reflex. Results. In the outer retina, eye blast caused retinal pigment epithelium vacuoles and rare retinal detachments followed by regional cell death. Labeling for nitrotyrosine and markers of pyroptosis (caspase-1) and necroptosis (receptor-interacting protein kinases-1, -3) increased, primarily in the inner retina, after blast. Caspase-1 labeling was restricted primarily to the starburst amacrine cells. A few degenerating axons were detected at 28 days post blast. Despite a lack of substantial cell death or decreased ERG, there was a deficit in visual acuity after blast. Conclusions. Oxidative stress, neuroinflammation, and cell death became increasingly prevalent, over time post blast suggestive of an ongoing neurodegenerative response. Outer retinal changes either resolved or remained focal. In contrast, inner retinal changes were more robust and spread from focal regions to the entire retina over time post blast. Our model of eye blast trauma causes molecular changes and a decrease in visual acuity within the first month post blast despite a lack of overt eye injury. This subtle response matches the delayed presentation of visual deficits in some blast-exposed Veterans. PMID:24994864

  20. 29 CFR 1926.912 - Underwater blasting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...currents from galvanic action of the metals and water. (c) Only water-resistant blasting caps and detonating cords shall be used...blast shall be fired while any person is in the water. (f) Blasting flags shall be...

  1. Ground Granulated Blast Furnace Slag

    Microsoft Academic Search

    Rafat Siddique; Mohammad Iqbal Khan

    \\u000a Ground granulated blast furnace slag (GGBS) is a by-product from the blast-furnaces used to make iron. Blast-furnaces are\\u000a fed with controlled mixture of iron-ore, coke and limestone, and operated at a temperature of about 1,500°C. When iron-ore,\\u000a coke and limestone melt in the blast furnace, two products are produced—molten iron, and molten slag. The molten slag is lighter\\u000a and floats

  2. Characterising the acceleration phase of blast wave formation

    NASA Astrophysics Data System (ADS)

    Fox, T. E.; Robinson, A. P. L.; Schmitz, H.; Pasley, J.

    2014-10-01

    Intensely heated, localised regions in uniform fluids will rapidly expand and generate an outwardly propagating blast wave. The Sedov-Taylor self-similar solution for such blast waves has long been studied and applied to a variety of scenarios. A characteristic time for their formation has also long been identified using dimensional analysis, which by its very nature, can offer several interpretations. We propose that, rather than simply being a characteristic time, it may be interpreted as the definitive time taken for a blast wave resulting from an intense explosion in a uniform media to contain its maximum kinetic energy. A scaling relation for this measure of the acceleration phase, preceding the establishment of the blast wave, is presented and confirmed using a 1D planar hydrodynamic model.

  3. Removal of phosphate from aqueous solution with blast furnace slag.

    PubMed

    Oguz, Ensar

    2004-10-18

    Blast furnace slag was used to remove phosphate from aqueous solutions. The influence of pH, temperature, agitation rate, and blast furnace slag dosage on phosphate removal was investigated by conducting a series of batch adsorption experiments. In addition, the yield and mechanisms of phosphate removal were explained on the basis of the results of X-ray spectroscopy, measurements of zeta potential of particles, specific surface area, and images of scanning electron microscopy (SEM) of the particles before and after adsorption. The specific surface area of the blast furnace slag was 0.4m(2)g(-1). The removal of phosphate predominantly has taken place by a precipitation mechanism and weak physical interactions between the surface of adsorbent and the metallic salts of phosphate. In this study, phosphate removal in excess of 99% was obtained, and it was concluded that blast furnace slag is an efficient adsorbent for the removal of phosphate from solution. PMID:15511583

  4. Fragmentation, Cost and Environmental Effects of Plaster Stemming Method for Blasting at A Basalt Quarry

    NASA Astrophysics Data System (ADS)

    Cevizci, Halim

    2014-10-01

    In this study, the plaster stemming application for blasting at a basalt quarry is studied. Drill cuttings are generally used in open pits and quarries as the most common stemming material since these are most readily available at blast sites. However, dry drill cuttings eject very easily from blastholes without offering much resistance to blast energy. The plaster stemming method has been found to be better than the drill cuttings stemming method due to increased confinement inside the hole and better utilization of blast explosive energy in the rock. The main advantage of the new stemming method is the reduction in the cost of blasting. At a basalt quarry, blasting costs per unit volume of rock were reduced to 15% by increasing burden and spacing distances. In addition, better fragmentation was obtained by using the plaster stemming method. Blast trials showed that plaster stemming produced finer material. In the same blast tests, +30 cm size fragments were reduced to 47.3% of the total, compared to 32.6% in the conventional method of drill cuttings stemming. With this method of stemming, vibration and air shock values increased slightly due to more blast energy being available for rock breakage but generally these increased values were small and stayed under the permitted limit for blast damage criteria unless measuring distance is too close.

  5. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    Dr. M.A. Ebadian

    2000-01-13

    The purpose of the project is to increase the productivity and economics of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCB's and lead-base paint and provides worker and environmental protection by continuously recycling the blast media and the full containment of the dust generated in the process.

  6. Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) into the Blast Furnace

    SciTech Connect

    Dr. Chenn Zhou

    2008-10-15

    Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process.

  7. Continuum modeling of neuronal cell under blast loading

    PubMed Central

    Jérusalem, Antoine; Dao, Ming

    2012-01-01

    Traumatic brain injuries have recently been put under the spotlight as one of the most important causes of accidental brain dysfunctions. Significant experimental and modeling efforts are thus ongoing to study the associated biological, mechanical and physical mechanisms. In the field of cell mechanics, progresses are also being made at the experimental and modeling levels to better characterize many of the cell functions such as differentiation, growth, migration and death, among others. The work presented here aims at bridging both efforts by proposing a continuum model of neuronal cell submitted to blast loading. In this approach, cytoplasm, nucleus and membrane (plus cortex) are differentiated in a representative cell geometry, and different material constitutive models are adequately chosen for each one. The material parameters are calibrated against published experimental work of cell nanoindentation at multiple rates. The final cell model is ultimately subjected to blast loading within a complete fluid-structure interaction computational framework. The results are compared to the nanoindentation simulation and the specific effects of the blast wave on the pressure and shear levels at the interfaces are identified. As a conclusion, the presented model successfully captures some of the intrinsic intracellular phenomena occurring during its deformation under blast loading and potentially leading to cell damage. It suggests more particularly the localization of damage at the nucleus membrane similarly to what has already been observed at the overall cell membrane. This degree of damage is additionally predicted to be worsened by a longer blast positive phase duration. As a conclusion, the proposed model ultimately provides a new three dimensional computational tool to evaluate intracellular damage during blast loading. PMID:22562014

  8. Minimization of Blast furnace Fuel Rate by Optimizing Burden and Gas Distribution

    SciTech Connect

    Dr. Chenn Zhou

    2012-08-15

    The goal of the research is to improve the competitive edge of steel mills by using the advanced CFD technology to optimize the gas and burden distributions inside a blast furnace for achieving the best gas utilization. A state-of-the-art 3-D CFD model has been developed for simulating the gas distribution inside a blast furnace at given burden conditions, burden distribution and blast parameters. The comprehensive 3-D CFD model has been validated by plant measurement data from an actual blast furnace. Validation of the sub-models is also achieved. The user friendly software package named Blast Furnace Shaft Simulator (BFSS) has been developed to simulate the blast furnace shaft process. The research has significant benefits to the steel industry with high productivity, low energy consumption, and improved environment.

  9. Determination of explosive blast loading equivalencies with an explosively driven shock tube

    SciTech Connect

    Jackson, Scott I [Los Alamos National Laboratory; Hill, Larry G [Los Alamos National Laboratory; Morris, John S [Los Alamos National Laboratory

    2009-01-01

    Recently there has been significant interest in evaluating the potential of many different non-ideal energetic materials to cause blast damage. We present a method intended to quantitatively compare the blast loading generated by different energetic materials through use of an explosively driven shock tube. The test explosive is placed at the closed breech end of the tube and initiated with a booster charge. The resulting shock waves are then contained and focused by the tube walls to form a quasi-one-dimensional blast wave. Pressure transducers along the tube wall measure the blast overpressure versus distance from the source and allow the use of the one-dimensional blast scaling relationship to determine the energy deposited into the blast wave per unit mass of test explosive. These values are then compared for different explosives of interest and to other methods of equivalency determination.

  10. Characterization of viscoelastic materials for low-magnitude blast mitigation

    NASA Astrophysics Data System (ADS)

    Bartyczak, S.; Mock, W.

    2014-05-01

    Recent research indicates that exposure to low amplitude blast waves, such as IED detonation or multiple firings of a weapon, causes damage to brain tissue resulting in Traumatic Brain Injury (TBI) and Post Traumatic Stress Disorder (PTSD). Current combat helmets are not sufficiently protecting warfighters from this danger and the effects are debilitating, costly, and long-lasting. The objective of the present work is to evaluate the blast mitigating behavior of current helmet materials and new materials designed for blast mitigation using a test fixture recently developed at the Naval Surface Warfare Center Dahlgren Division for use with an existing gas gun. The 40-mm-bore gas gun was used as a shock tube to generate blast waves (ranging from 0.5 to 2 bar) in the test fixture mounted on the gun muzzle. A fast opening valve was used to release helium gas from the breech which formed into a blast wave and impacted instrumented targets in the test fixture. Blast attenuation of selected materials was determined through the measurement of stress data in front of and behind the target. Materials evaluated in this research include polyurethane foam from currently fielded US Army and Marine Corps helmets, polyurea 1000, and three hardnesses of Sorbothane (48, 58, and 70 durometer, Shore 00). Polyurea 1000 and 6061-T6 aluminum were used to calibrate the stress gauges.

  11. Investigation of blast-induced traumatic brain injury

    PubMed Central

    Ludwigsen, John S.; Ford, Corey C.

    2014-01-01

    Objective Many troops deployed in Iraq and Afghanistan have sustained blast-related, closed-head injuries from being within non-lethal distance of detonated explosive devices. Little is known, however, about the mechanisms associated with blast exposure that give rise to traumatic brain injury (TBI). This study attempts to identify the precise conditions of focused stress wave energy within the brain, resulting from blast exposure, which will correlate with a threshold for persistent brain injury. Methods This study developed and validated a set of modelling tools to simulate blast loading to the human head. Using these tools, the blast-induced, early-time intracranial wave motions that lead to focal brain damage were simulated. Results The simulations predict the deposition of three distinct wave energy components, two of which can be related to injury-inducing mechanisms, namely cavitation and shear. Furthermore, the results suggest that the spatial distributions of these damaging energy components are independent of blast direction. Conclusions The predictions reported herein will simplify efforts to correlate simulation predictions with clinical measures of TBI and aid in the development of protective headwear. PMID:24766453

  12. Finite element modeling of blast lung injury in sheep.

    PubMed

    Gibbons, Melissa M; Dang, Xinglai; Adkins, Mark; Powell, Brian; Chan, Philemon

    2015-04-01

    A detailed 3D finite element model (FEM) of the sheep thorax was developed to predict heterogeneous and volumetric lung injury due to blast. A shared node mesh of the sheep thorax was constructed from a computed tomography (CT) scan of a sheep cadaver, and while most material properties were taken from literature, an elastic-plastic material model was used for the ribs based on three-point bending experiments performed on sheep rib specimens. Anesthetized sheep were blasted in an enclosure, and blast overpressure data were collected using the blast test device (BTD), while surface lung injury was quantified during necropsy. Matching blasts were simulated using the sheep thorax FEM. Surface lung injury in the FEM was matched to pathology reports by setting a threshold value of the scalar output termed the strain product (maximum value of the dot product of strain and strain-rate vectors over all simulation time) in the surface elements. Volumetric lung injury was quantified by applying the threshold value to all elements in the model lungs, and a correlation was found between predicted volumetric injury and measured postblast lung weights. All predictions are made for the left and right lungs separately. This work represents a significant step toward the prediction of localized and heterogeneous blast lung injury, as well as volumetric injury, which was not recorded during field testing for sheep. PMID:25411822

  13. Centrifugal shot blast system

    SciTech Connect

    NONE

    1998-02-01

    This report describes a demonstration of Concrete cleaning, Inc., modified centrifugal shot blast technology to remove the paint coating from concrete flooring. This demonstration is part of the Chicago Pile-5 (CP-5) Large-Scale Demonstration Project (LSDP) sponsored by the US Department of Energy (DOE), office of Science and Technology (OST), Deactivation and Decommissioning Focus Area (DDFA). The objective of the LSDP is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) CP-5 Research Reactor. The purpose of the LSDP is to demonstrate that using innovative and improved decontamination and decommissioning (D and D) technologies from various sources can result in significant benefits, such as decreased cost and increased health and safety, as compared with baseline D and D technologies. Potential markets exist for the innovative centrifugal shot blast system at the following sites: Fernald Environmental Management Project, Los Alamos, Nevada, Oak Ridge Y-12 and K-25, Paducah, Portsmouth Gaseous Diffusion site, and the Savannah River Site. This information is based on a revision to the OST Linkage Tables dated August 4, 1997.

  14. A systematic exposition of the conservation equations for blast waves.

    NASA Technical Reports Server (NTRS)

    Oppenheim, A. K.; Lundstrom, E. A.; Kuhl, A. L.; Kamel, M. M.

    1971-01-01

    In order to provide a rational background for the analysis of experimental observations of blast wave phenomena, the conservation equations governing their nonsteady flow field are formulated in a general manner, without the usual restrictions imposed by an equation of state, and with proper account taken, by means of source terms, of other effects which, besides the inertial terms that conventionally dominate these equations, can affect the flow. Taking advantage of the fact that a blast wave can be generally considered as a spatially one-dimensional flow field whose nonsteady behavior can be regarded, consequently, as a function of just two independent variables, two generalized blast wave coordinates are introduced, one associated with the front of the blast wave and the other with its flow field. The conservation equations are accordingly transformed into this coordinate system, acquiring thereby a comprehensive character, in that they refer then to any frame of reference, being applicable, in particular, to problems involving either space or time profiles of the gas-dynamic parameters in the Eulerian system, or time profiles in the Lagrangian system.

  15. Applications of network BLAST server.

    PubMed

    Madden, T L; Tatusov, R L; Zhang, J

    1996-01-01

    The sequence databases continue to grow at an extraordinary rate. Contributions come from both small laboratories and large-scale projects, such as the Merck EST project. This growth has placed new demands on computational sequence comparison tools such as BLAST. Even now it is no longer practical to evaluate some BLAST reports manually; it is necessary to filter the output by, for example, organism, source, or degree of annotation. The new network BLAST service makes such tools possible. It is also possible to present BLAST output in different formats, such as BLANCE. Perhaps most important of all, it becomes simple to call BLAST from another application, making it one step within an integrated system. This makes the automated preparation of sequence evaluations that include BLAST runs possible. In the near future we expect to see a number of applications that use the network BLAST interface to help molecular biologists search against a database that is growing not only in size but in biological richness. PMID:8743682

  16. Spurious phenomena occurring during current measurement on ultra-thin dielectric layers: From electro-thermal effects to surface damage

    SciTech Connect

    Grandfond, A.; Gautier, B.; Militaru, L.; Albertini, D.; Descamps-Mandine, A. [Institut des Nanotechnologies de Lyon (INL), UMR CNRS 5270, INSA de Lyon, 7 Avenue Jean Capelle, 69621 Villeurbanne CEDEX (France)

    2014-04-07

    In this paper, the conduction properties of dielectric ultra-thin layers are studied using atomic force microscopy. Especially, the conductive-atomic force microscope allows to measure the leakage current at the nanoscale and to study the degradation mechanisms locally. Nonetheless, the dielectric layer seems to be damaged by a technique's specific phenomenon: hillocks appear when a positive tip bias is applied on different dielectrics. In this paper, the formation of these hillocks is studied. Contrary to what is observed during the dielectric breakdown, the conductivity is reduced after hillocks formation which occurs after the dielectric breakdown. Moreover, we have observed the formation of cavities in the silicon substrate linked to the formation of hillocks, which is not compatible with a swelling process (as dielectric breakdown induced epitaxy). We propose that these results may be explained by an electro-thermal effect due to the large dissipated energy, maybe combined with the oxidation of the substrate. Finally, the interdependence of measurements is demonstrated during serial acquisition.

  17. Quantifying transient 3D dynamical phenomena of single mRNA particles in live yeast cell measurements.

    PubMed

    Calderon, Christopher P; Thompson, Michael A; Casolari, Jason M; Paffenroth, Randy C; Moerner, W E

    2013-12-12

    Single-particle tracking (SPT) has been extensively used to obtain information about diffusion and directed motion in a wide range of biological applications. Recently, new methods have appeared for obtaining precise (10s of nm) spatial information in three dimensions (3D) with high temporal resolution (measurements obtained every 4 ms), which promise to more accurately sense the true dynamical behavior in the natural 3D cellular environment. Despite the quantitative 3D tracking information, the range of mathematical methods for extracting information about the underlying system has been limited mostly to mean-squared displacement analysis and other techniques not accounting for complex 3D kinetic interactions. There is a great need for new analysis tools aiming to more fully extract the biological information content from in vivo SPT measurements. High-resolution SPT experimental data has enormous potential to objectively scrutinize various proposed mechanistic schemes arising from theoretical biophysics and cell biology. At the same time, methods for rigorously checking the statistical consistency of both model assumptions and estimated parameters against observed experimental data (i.e., goodness-of-fit tests) have not received great attention. We demonstrate methods enabling (1) estimation of the parameters of 3D stochastic differential equation (SDE) models of the underlying dynamics given only one trajectory; and (2) construction of hypothesis tests checking the consistency of the fitted model with the observed trajectory so that extracted parameters are not overinterpreted (the tools are applicable to linear or nonlinear SDEs calibrated from nonstationary time series data). The approach is demonstrated on high-resolution 3D trajectories of single ARG3 mRNA particles in yeast cells in order to show the power of the methods in detecting signatures of transient directed transport. The methods presented are generally relevant to a wide variety of 2D and 3D SPT tracking applications. PMID:24015725

  18. Crack Response to Blast Vibrations and Moisture Induced Volumetric Changes in Foundation Soils

    E-print Network

    * Structural distortion from overloading, creep, etc. Responses to changes in the foundation soil are usuallyCrack Response to Blast Vibrations and Moisture Induced Volumetric Changes in Foundation Soils By C changes in foundation soils induced by natural events. These natural phenomena include changes

  19. Blast From the Past

    NSDL National Science Digital Library

    A recently recovered deep-sea core supports theories that an asteroid collided with the earth 65 million years ago, around the time of the extinction of the dinosaurs. The Smithsonian Institution National Museum of Natural History's new site, Blast from the Past, contains details on this cataclysmic event. Colorful graphics provide conceptual illustrations of the asteroid impact and aftermath, accompanied by photographs of the deep-sea core. Text summaries, followed by bibliographic references, describe the asteroid hypothesis, the Cretaceous/Tertiary (K/T) boundary, and the utility of deep-sea cores. With links to other paleobiological sites and related museum exhibits, this site is a useful resource for those wanting to know more about fateful asteroid impacts.

  20. Portable convertible blast effects shield

    DOEpatents

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A. (Livermore, CA)

    2011-03-15

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more frusto-conically-tapered telescoping rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration by the friction fit of adjacent pairs of frusto-conically-tapered rings to each other.

  1. Portable convertible blast effects shield

    DOEpatents

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler,; Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

    2010-10-26

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  2. Portable convertible blast effects shield

    DOEpatents

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

    2007-05-22

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  3. Blast furnace slags as sorbents of phosphate from water solutions

    Microsoft Academic Search

    Bruno Kostura; Hana Kulveitová; Juraj Leško

    2005-01-01

    The paper is focused on the sorption of phosphorus from aqueous solutions by crystalline and amorphous blast furnace slags. Slag sorption kinetics were measured, adsorption tests were carried out and the effect of acidification on the sorption properties of slags was studied. The kinetic measurements confirmed that the sorption of phosphorus on crystalline as well as amorphous slags can be

  4. Proceedings of the fourth mini-symposium on explosives and blasting research

    SciTech Connect

    Not Available

    1991-01-01

    Eleven papers were presented at this mini-symposium covering the following topics: estimation of damage produced by blasting; stress measurements in coal; channel effect for ANFO slurries and emulsions; design of blasts for surface coal mining; measurement of fragmentation efficiency; measurement of amplitude-frequency components of ground vibrations; computer-aided design for millisecond-delayed initiators; safety against lightning in blast systems; design of a mechanical stemming aid; and measurement of explosive reactivity of explosive contaminated solid wastes. All papers have been processed separately for inclusion on the data base.

  5. BLAST: The Balloon-Borne Large Aperture Submillimeter Telescope

    NASA Technical Reports Server (NTRS)

    Devlin, Mark; Ade, Peter; Bock, Jamie; Dicker, Simon; Griffin, Matt; Gunderson, Josh; Halpern, Mark; Hargrave, Peter; Hughes, David; Klein, Jeff

    2004-01-01

    BLAST is the Balloon-borne Large-Aperture Sub-millimeter Telescope. It will fly from a Long Duration Balloon (LDB) platform from Antarctica. The telescope design incorporates a 2 m primary mirror with large-format bolometer arrays operating at 250, 350 and 500 microns. By providing the first sensitive large-area (10 sq. deg.) sub-mm surveys at these wavelengths, BLAST will address some of the most important galactic and cosmological questions regarding the formation and evolution of stars, galaxies and clusters. Galactic and extragalactic BLAST surveys will: (1) identify large numbers of high-redshift galaxies; (2) measure photometric redshifts, rest-frame FIR luminosities and star formation rates thereby constraining the evolutionary history of the galaxies that produce the FIR and sub-mm background; (3) measure cold pre-stellar sources associated with the earliest stages of star and planet formation; (4) make high-resolution maps of diffuse galactic emission over a wide range of galactic latitudes. In addition to achieving the above scientific goals, the exciting legacy of the BLAST LDB experiment will be a catalogue of 3000-5000 extragalactic sub-mm sources and a 100 sq. deg. sub-mm galactic plane survey. Multi-frequency follow-up observations from SIRTF, ASTRO-F, and Herschel, together with spectroscopic observations and sub-arcsecond imaging from ALMA are essential to understand the physical nature of the BLAST sources.

  6. Shock wave focusing phenomena

    Microsoft Academic Search

    H. Groenig

    1986-01-01

    A review is presented of recent studies of the focusing of concave shock waves in gases, fluids and solids by curved boundaries. Various shock wave focusing apparatus that have been tested are described, including a detonation chamber, a setup for focusing weak blast waves and a configuration for obtaining time-stepped shadowgraphs of converging cylindrical shocks. Sample velocity profile data are

  7. The impact of blasting on excavation design -- A geomechanics approach

    SciTech Connect

    Andrieux, P.; Drolet, A. [Noranda Technology Centre, Pointe-Claire, Quebec (Canada); McKenzie, C. [Blastronics Australia Pty, Ltd., Brisbane, Queensland (Australia); Heilig, J. [BLM Blastronics Canada Ltd., Sudbury, Ontario (Canada)

    1994-12-31

    It is widely accepted that both underground and surface blasting operations can de-stabilize excavations to the point where it can threaten the feasibility of mining through personnel safety or ore dilution. Research has been undertaken to outline a practical method in which the impact of blasting will be accounted for during the early excavation design stage by modelling, and during the following production stages by monitoring rock response to blasting operations. Of the many factors influencing the stability of excavations in rock, a critical one is the natural geological structure. The research work presented in this paper is part of a major effort aimed at integrating blast design with this aspect of rock mechanics excavation design. The chosen approach considers vibrations to be the primary cause for blast-induced rock damage in underground operations, where it is argued that gas effects have a lesser impact due to the usually high stresses confining fractures. Tests were conducted during the Fall of 1992 in an underground experimental drift surrounded by two tunnels designed for observation and instrumentation purposes. A total of five rounds were blasted in the experimental drift: each time the blast design was altered to increase the amount of damage in the test tunnel, which was then observed and quantified from the observation drifts. Analysis of the results focused on establishing a relationship between vibration levels and the extent or degree of fracturing induced. Other practical indirect measurement methods for assessing the extent of fractures in the rock mass, such as high frequency seismic methods, high resolution displacement analysis using a time domain reflectometry (TDR) method, and radar mapping, were also studied by the multi-disciplinary research team.

  8. Thermal Wave Phenomena

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This map from the MGS Horizon Sensor Assembly (HORSE) shows middle atmospheric temperatures near the 1 mbar level of Mars between Ls 170 to 175 (approx. July 14 - 23, 1999). Local Mars times between 1:30 and 4:30 AM are included. Infrared radiation measured by the Mars Horizon Sensor Assembly was used to make the map. That device continuously views the 'limb' of Mars in four directions, to help orient the spacecraft instruments to the nadir: straight down.

    The map shows thermal wave phenomena that are caused by the large topographic variety of Mars' surface, as well the latitudinally symmetric behavior expected at this time of year near the equinox.

  9. Temporally resolved planar measurements of transient phenomena in a partially pre-mixed swirl flame in a gas turbine model combustor

    SciTech Connect

    Boxx, I.; Stoehr, M.; Meier, W. [Institut fuer Verbrennungstechnik, Deutsches Zentrum fuer Luft-und Raumfahrt (DLR), Pfaffenwaldring 38-40, D-70569 Stuttgart (Germany); Carter, C. [Air Force Research Laboratory (AFRL)/PRAS, 1950 Fifth St, Wright-Patterson AFB, OH (United States)

    2010-08-15

    This paper presents observations and analysis of the time-dependent behavior of a 10 kW partially pre-mixed, swirl-stabilized methane-air flame exhibiting self-excited thermo-acoustic oscillations. This analysis is based on a series of measurements wherein particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF) of the OH radical were performed simultaneously at 5 kHz repetition rate over durations of 0.8 s. Chemiluminescence imaging of the OH{sup *} radical was performed separately, also at 5 kHz over 0.8 s acquisition runs. These measurements were of sufficient sampling frequency and duration to extract usable spatial and temporal frequency information on the medium to large-scale flow-field and heat-release characteristics of the flame. This analysis is used to more fully characterize the interaction between the self-excited thermo-acoustic oscillations and the dominant flow-field structure of this flame, a precessing vortex core (PVC) present in the inner recirculation zone. Interpretation of individual measurement sequences yielded insight into various physical phenomena and the underlying mechanisms driving flame dynamics. It is observed for this flame that location of the reaction zone tracks large-scale fluctuations in axial velocity and also conforms to the passage of large-scale vortical structures through the flow-field. Local extinction of the reaction zone in regions of persistently high principal compressive strain is observed. Such extinctions, however, are seen to be self healing and thus do not induce blowout. Indications of auto-ignition in regions of unburned gas near the exit are also observed. Probable auto-ignition events are frequently observed coincident with the centers of large-scale vortical structures, suggesting the phenomenon is linked to the enhanced mixing and longer residence times associated with fluid at the core of the PVC as it moves through the flame. (author)

  10. A General Viscosity Model for Molten Blast Furnace Slag

    NASA Astrophysics Data System (ADS)

    Gan, Lei; Lai, Chaobin

    2014-06-01

    Blast furnace slag is the most abundant slag in the steel industry. Its metallurgical properties are determined to a great extent by its viscosity. Therefore, it is necessary to establish a reliable viscosity model for blast furnace slag. In the current work, a simple, accurate, and physically meaningful viscosity model for a wide composition range of blast furnace slags is developed based on the Vogel-Fulcher-Tammann (VFT) equation: log ? = A + B/( T - C). The model is calibrated by a database containing 365 compositions and 1233 measurements of synthetic and industrial slags. The parameter A has a value of -3.10. The parameters B and C are related to the mass fraction ratio of (CaO + MgO) to (SiO2 + Al2O3) and liquidus temperature of the slag, respectively. Present viscosity model accurately predicts the viscosity of blast furnace slag with relative average error (?) of 0.211 (±0.180) and root mean square error (RMSE) of 0.239 Pa·s. A slight modification of this model can also predict the glass transition temperature of blast furnace slag satisfactorily.

  11. Predictions of Experimentally Observed Stochastic Ground Vibrations Induced by Blasting

    PubMed Central

    Kosti?, Sr?an; Perc, Matjaž; Vasovi?, Nebojša; Trajkovi?, Slobodan

    2013-01-01

    In the present paper, we investigate the blast induced ground motion recorded at the limestone quarry “Suva Vrela” near Kosjeri?, which is located in the western part of Serbia. We examine the recorded signals by means of surrogate data methods and a determinism test, in order to determine whether the recorded ground velocity is stochastic or deterministic in nature. Longitudinal, transversal and the vertical ground motion component are analyzed at three monitoring points that are located at different distances from the blasting source. The analysis reveals that the recordings belong to a class of stationary linear stochastic processes with Gaussian inputs, which could be distorted by a monotonic, instantaneous, time-independent nonlinear function. Low determinism factors obtained with the determinism test further confirm the stochastic nature of the recordings. Guided by the outcome of time series analysis, we propose an improved prediction model for the peak particle velocity based on a neural network. We show that, while conventional predictors fail to provide acceptable prediction accuracy, the neural network model with four main blast parameters as input, namely total charge, maximum charge per delay, distance from the blasting source to the measuring point, and hole depth, delivers significantly more accurate predictions that may be applicable on site. We also perform a sensitivity analysis, which reveals that the distance from the blasting source has the strongest influence on the final value of the peak particle velocity. This is in full agreement with previous observations and theory, thus additionally validating our methodology and main conclusions. PMID:24358140

  12. Teaching optical phenomena with Tracker

    NASA Astrophysics Data System (ADS)

    Rodrigues, M.; Simeão Carvalho, P.

    2014-11-01

    Since the invention and dissemination of domestic laser pointers, observing optical phenomena is a relatively easy task. Any student can buy a laser and experience at home, in a qualitative way, the reflection, refraction and even diffraction phenomena of light. However, quantitative experiments need instruments of high precision that have a relatively complex setup. Fortunately, nowadays it is possible to analyse optical phenomena in a simple and quantitative way using the freeware video analysis software ‘Tracker’. In this paper, we show the advantages of video-based experimental activities for teaching concepts in optics. We intend to show: (a) how easy the study of such phenomena can be, even at home, because only simple materials are needed, and Tracker provides the necessary measuring instruments; and (b) how we can use Tracker to improve students’ understanding of some optical concepts. We give examples using video modelling to study the laws of reflection, Snell’s laws, focal distances in lenses and mirrors, and diffraction phenomena, which we hope will motivate teachers to implement it in their own classes and schools.

  13. Cosmic ray origins in supernova blast waves

    NASA Astrophysics Data System (ADS)

    Bell, A. R.

    2015-03-01

    We extend the self-similar solution derived by Chevalier for a Sedov blast wave accelerating cosmic rays (CR) to show that the Galactic CR population can be divided into (A) CR with energies above ˜200 GeV released upstream during CR acceleration by supernova remnants (SNR), (B) CR advected into the interior of the SNR during expansion and then released from the SNR at the end of its life to provide the Galactic CR component below ˜200 GeV. The intersection between the two populations may correspond to a measured change in the Galactic CR spectral index at this energy.

  14. Blasting Rocks and Blasting Cars Applied Engineering

    ScienceCinema

    LBNL

    2009-09-01

    June 30, 2004 Berkeley Lab lecture: Deb Hopkins works with industries like automobile, mining and paper to improve their evaluation and measuring techniques. For several years, she has coordinated ... June 30, 2004 Berkeley Lab lecture: Deb Hopkins works with industries like automobile, mining and paper to improve their evaluation and measuring techniques. For several years, she has coordinated a program at Berkeley Lab funded under the Partnership for a New Generation of Vehicles, a collaboration between the federal government and the U.S. Council for Automotive Research. Nondestructive evaluation techniques to test a car's structural integrity are being developed for auto assembly lines.

  15. Blasting Rocks and Blasting Cars Applied Engineering

    SciTech Connect

    LBNL

    2008-07-02

    June 30, 2004 Berkeley Lab lecture: Deb Hopkins works with industries like automobile, mining and paper to improve their evaluation and measuring techniques. For several years, she has coordinated ... June 30, 2004 Berkeley Lab lecture: Deb Hopkins works with industries like automobile, mining and paper to improve their evaluation and measuring techniques. For several years, she has coordinated a program at Berkeley Lab funded under the Partnership for a New Generation of Vehicles, a collaboration between the federal government and the U.S. Council for Automotive Research. Nondestructive evaluation techniques to test a car's structural integrity are being developed for auto assembly lines.

  16. How to Measure Qualitative Understanding of DC-Circuit Phenomena - Taking a Closer Look at the External Representations of 9-Year-Olds

    NASA Astrophysics Data System (ADS)

    Kallunki, Veera

    2013-04-01

    Pupils' qualitative understanding of DC-circuit phenomena is reported to be weak. In numerous research reports lists of problems in understanding the functioning of simple DC-circuits have been presented. So-called mental model surveys have uncovered difficulties in different age groups, and in different phases of instruction. In this study, the concept of qualitative understanding, and the content or position of reported mental models of DC-circuit phenomena are discussed. On the grounds of this review, new tools for investigating qualitative understanding and analysing external representations of DC-circuit phenomena are presented. According to this approach, the external representations of DC-circuit phenomena that describe pupils' expressed conceptions of the topic should include both empirical-based models and theoretical explanations. In the empirical part of this study , third-graders (9-year-olds) learning DC-circuit phenomena in a comprehensive school in a small group were scrutinised. The focus of the study is the external representations manifested in the talk of the small group. The study challenges earlier studies, which claim that children exhibit a wide range of qualitative difficulties when learning DC-circuit phenomena. In this study it will be shown that even in the case of abstract subject matter like DC-circuit phenomena, small groups that highlight empirical-based modelling and activate talk can be a fruitful learning environment, where pupils' qualitative understanding really develops. Thus, the study proposes taking a closer look at pupils' external representations concerning DC-circuit phenomena.

  17. Nucleon form factors and charge densities from the BLAST Experiment

    NASA Astrophysics Data System (ADS)

    Crawford, Chris

    2007-10-01

    The BLAST experiment was designed to study in a systematic manner the spin-dependent electromagnetic interaction. Utilizing the polarized electron beam in the MIT-Bates South Hall Storage Ring, highly-polarized isotopically pure targets of hydrogen and deuterium, and the symmetric general purpose BLAST detector; precise measurements have been made which permit the extraction of the proton and neutron charge and magnetic form factors. The neutron electric form factor especially is now known to a precision comparable to that of the other nucleon form factors. These results, together with previously existing data, will constrain theoretical models constructed to explain the detailed structure of nucleon form factors.

  18. Ex vivo Characterization of Blast Wave Impact and Spinal Cord Tissue Deformation

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Gao, Jian; Connell, Sean; Shi, Riyi

    2010-11-01

    Primary blast injury on central nervous system is responsible for many of the war related casualties and mortalities. An ex vivo model system is developed to introduce a blast wave, generated from a shock tube, directly to spinal cord tissue sample. A high-speed shadowgraph system is utilized to visualize the development of the blast wave and its interaction with tissue sample. Surface deformation of the tissue sample is also measured for the analysis of internal stress and possible injury occurred within the tissue sample. Understanding the temporal development of the blast-tissue interaction provides valuable input for modeling blast-induced neurotrauma. Tracking the sample surface deformation as a function of time provides realistic boundary conditions for numerical simulation of injury process.

  19. Measuring Your Peak Flow Rate

    MedlinePLUS

    ... air flows from your lungs in one “fast blast.” In other words, the meter measures your ability ... as quickly as possible. Blow a “fast hard blast” rather than “slowly blowing” until you have emptied ...

  20. MOLECULAR CONTROL OF THE RICE BLAST DISEASE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease caused by Magnaporthe grisea is a major constraint to rice production worldwide. The rice blast system is one of the best-characterized monocot model systems. The goal of this project is to understand molecular mechanisms of disease resistance using rice blast as a model system....

  1. 29 CFR 1926.912 - Underwater blasting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...loading tube when tube is necessary. (d) No blast shall be fired while any vessel under way is closer...anchored within 1,500 feet shall be notified before a blast is fired. (e) No blast shall be fired while any swimming or diving...

  2. Simulation of Blast Waves with Headwind

    NASA Technical Reports Server (NTRS)

    Olsen, Michael E.; Lawrence, Scott W.; Klopfer, Goetz H.; Mathias, Dovan; Onufer, Jeff T.

    2005-01-01

    The blast wave resulting from an explosion was simulated to provide guidance for models estimating risks for human spacecraft flight. Simulations included effects of headwind on blast propagation, Blasts were modelled as an initial value problem with a uniform high energy sphere expanding into an ambient field. Both still air and cases with headwind were calculated.

  3. Div-BLAST: Diversification of Sequence Search Results

    PubMed Central

    Eser, Elif; Can, Tolga; Ferhatosmano?lu, Hakan

    2014-01-01

    Sequence similarity tools, such as BLAST, seek sequences most similar to a query from a database of sequences. They return results significantly similar to the query sequence and that are typically highly similar to each other. Most sequence analysis tasks in bioinformatics require an exploratory approach, where the initial results guide the user to new searches. However, diversity has not yet been considered an integral component of sequence search tools for this discipline. Some redundancy can be avoided by introducing non-redundancy during database construction, but it is not feasible to dynamically set a level of non-redundancy tailored to a query sequence. We introduce the problem of diverse search and browsing in sequence databases that produce non-redundant results optimized for any given query. We define diversity measures for sequences and propose methods to obtain diverse results extracted from current sequence similarity search tools. We also propose a new measure to evaluate the diversity of a set of sequences that is returned as a result of a sequence similarity query. We evaluate the effectiveness of the proposed methods in post-processing BLAST and PSI-BLAST results. We also assess the functional diversity of the returned results based on available Gene Ontology annotations. Additionally, we include a comparison with a current redundancy elimination tool, CD-HIT. Our experiments show that the proposed methods are able to achieve more diverse yet significant result sets compared to static non-redundancy approaches. In both sequence-based and functional diversity evaluation, the proposed diversification methods significantly outperform original BLAST results and other baselines. A web based tool implementing the proposed methods, Div-BLAST, can be accessed at cedar.cs.bilkent.edu.tr/Div-BLAST PMID:25531115

  4. Idaho National Laboratory Experimental Program to Measure the Flow Phenomena in a Scaled Model of a Prismatic Gas-Cooled Reactor Lower Plenum for Validation of CFD Codes

    SciTech Connect

    Hugh M. McIlroy Jr.; Donald M. McEligot; Robert J. Pink

    2008-09-01

    The experimental program that is being conducted at the Matched Index-of-Refraction (MIR) Flow Facility at Idaho National Laboratory (INL) to obtain benchmark data on measurements of flow phenomena in a scaled model of a prismatic gas-cooled reactor lower plenum using 3-D Particle Image Velocimetry (PIV) is presented. A description of the scaling analysis, experimental facility, 3-D PIV system, measurement uncertainties and analysis, experimental procedures and samples of the data sets that have been obtained are included. Samples of the data set that will be presented include mean-velocity-field and turbulence data in an approximately 1:7 scale model of a region of the lower plenum of a typical prismatic gas-cooled reactor (GCR) similar to a General Atomics Gas-Turbine-Modular Helium Reactor (GTMHR) design. This experiment has been selected as the first Standard Problem endorsed by the Generation IV International Forum. The flow in the lower plenum consists of multiple jets injected into a confined cross flow - with obstructions. The model consists of a row of full circular posts along its centerline with half-posts on the two parallel walls to approximate flow scaled to that expected from the staggered parallel rows of posts in the reactor design. The model is fabricated from clear, fused quartz to match the refractive-index of the mineral oil working fluid. The benefit of the MIR technique is that it permits high-quality measurements to be obtained without locating intrusive transducers that disturb the flow field and without distortion of the optical paths. An advantage of the INL MIR system is its large size which allows improved spatial and temporal resolution compared to similar facilities at smaller scales. Results concentrate on the region of the lower plenum near its far reflector wall (away from the outlet duct). Inlet jet Reynolds numbers (based on the jet diameter and the time-mean average flow rate) are approximately 4,300 and 12,400. The measurements reveal developing, non-uniform flow in the inlet jets and complicated flow patterns in the model lower plenum. Data include three-dimensional vector plots, data displays along the coordinate planes (slices) and charts that describe the component flows at specific regions in the model. Information on inlet velocity profiles is also presented.

  5. Conserving Energy in Blast Freezers Using Variable Frequency Drives

    E-print Network

    Kolbe, E.; Ling, Q.; Wheeler, G.

    2004-01-01

    A stationary blast freezer processing 22-lb cartons of sardines in 19,000 pound lots was modified to improve efficiency and to conserve energy. Baffles were first added to produce uniform air flow. Maximum measured freeze times of 12.6 hours fell...

  6. Behind Armor Blast (BAB) caused by shaped charges

    Microsoft Academic Search

    Werner Arnold; Frank K. Schäfer

    1999-01-01

    Steel targets were shot by shaped charges. Instead of using conventional copper liners, in this test series liners made of aluminium and magnesium were used. The jet velocities ranged from 5 to 7 mm\\/?s. Behind the steel target a large Behind Armor Blast (BAB) - effect occurred. The measurement of this BAB was carried out by pressure and temperature probes

  7. Positron impact ionization phenomena

    NASA Astrophysics Data System (ADS)

    Murtagh, Daniel James

    In the present work, a beam of positrons, obtained from a radioactive source (MNa) in conjunction with a W moderator and guided by a magnetic field, has been used to investigate low energy positron-impact ionization phenomena from atomic and molecular targets. For He below threshold, the investigation discovered vacuum contaminants in creased with gas load and hence concluded that the high 7-ray/ion signal observed by Szluinska and Laricchia (2004a) in Ne could not be safely attributed to annihila tion. A detailed measurement of the total ionization cross-section for He has been performed from below threshold for Ps formation to high energy. Combined with previously measured data and previously measured direct ionization cross-sections (Moxom et al 1996, Ashley et al 1996), a new determination of the positronium formation cross-section has been achieved and compared to other available experi mental measurements and theoretical calculations. Measurements of the excited state (n > 1) positronium formation cross-section for He and Ar have been performed and compared to available theoretical calcu lations. This work has been motivated both for a direct comparison with theory and to test the hypothesis that structure observed in the total (all n) positron ium formation cross-sections for the heavier noble gases, is due to excited state positronium formation (Laricchia et al 2002). The present study is unable to verify fully this hypothesis due to the experimental methods insensitivity to positronium formation in to the 2S or n > 2 states. However, the present results are close to the most sophisticated theoretical calculation of positronium formation into the 2P state (Campbell et al 1998).

  8. Blast waves in rotating media.

    NASA Technical Reports Server (NTRS)

    Rossner, L. F.

    1972-01-01

    The model investigated involves a cylindrically symmetric blast wave generated by an infinitely long line explosion in a cold and homogeneous gas rotating rigidly in its self-gravitational field. It is found that within the context of rotation in a gravitational field a blast wave will not adopt the one-zone form familiar from similarity solutions but, rather, a two-zone form. The inner compression zone arises as a response to the presence of the restoring force, which drives a rarefaction wave into the outer compression zone.

  9. Full-Trajectory Diagnosis of Laser-Driven Radiative Blast Waves in Search of Thermal Plasma Instabilities

    SciTech Connect

    Moore, A. S.; Gumbrell, E. T.; Lazarus, J.; Hohenberger, M.; Robinson, J. S.; Smith, R. A.; Plant, T. J. A.; Symes, D. R.; Dunne, M. [Plasma Physics Division, AWE Aldermaston, RG7 4PR. United Kingdom (United Kingdom); Laser Consortium, Blackett Laboratory, Imperial College, London SW7 2BZ. United Kingdom (United Kingdom); Ministry of Defence, Foxhill, Bath BA1 5AB. United Kingdom (United Kingdom); Central Laser Facility, Rutherford Appleton Laboratory, Oxfordshire OX11 0QX. United Kingdom (United Kingdom)

    2008-02-08

    Experimental investigations into the dynamics of cylindrical, laser-driven, high-Mach-number shocks are used to study the thermal cooling instability predicted to occur in astrophysical radiative blast waves. A streaked Schlieren technique measures the full blast-wave trajectory on a single-shot basis, which is key for observing shock velocity oscillations. Electron density profiles and deceleration parameters associated with radiative blast waves were recorded, enabling the calculation of important blast-wave parameters including the fraction of radiated energy, {epsilon}, as a function of time for comparison with radiation-hydrodynamics simulations.

  10. Blast vulnerability detected in novel blast-resistant germplasm.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research in artificially inoculated greenhouse tests and field nurseries identified new rice germplasm accession as being resistant to the common blast (Pyricularia grisea) races found in Arkansas (IB-1, IB-49, IC-17, IE-1, IE-1k, IG-1, and IH-1) and eliminated those accessions with major b...

  11. Methods for predicting rubble motion during blasting

    SciTech Connect

    Schamaun, J.T.

    1984-01-01

    Recent applications of explosives and blasting agents to rubble rock have led to requirements for more elaborate design and analysis methods. In most blasting uses, it is necessary not only to fracture the rock, but also to move the broken rubble in a predictable manner. Many in situ extraction techniques require rubblization to take place in a confined region where rock motion is a predominate factor in creating a permeable broken bed. In this paper, two analytical methods are presented which describe the large rubble motion during blasting. These methods provide the blast designer with a tool for evaluation and further refinement of blasting patterns and timing sequences.

  12. Alumina grit blasting parameters for surface preparation in the plasma spraying operation

    NASA Astrophysics Data System (ADS)

    Mellali, M.; Grimaud, A.; Leger, A. C.; Fauchais, P.; Lu, J.

    1997-06-01

    This paper examines how the grit blasting process influences the surface roughness of different sub-strates, the grit residue, and the grit erosion. The influence of grit blasting conditions on induced sub-strate residual stresses is also discussed. Aluminum alloy, cast iron, and hard steel were blasted with white alumina grits of 0.5,1, and 1.4 mm mean diameters. Grit blasting was performed using either a suction-type or a pressure-type machine equipped with straight nozzles made of B4C. The influence of the follow-ing parameters was studied: grit blasting distance (56 to 200 mm), blasting time (3 to 30 s), angle between nozzle and blasted surface (30°, 60°, 90°), and blasting pressure (0.2 to 0.7 MPa). The roughness of the substrate was characterized either by using a perthometer or by image analysis. The grit residue remain-ing at the blasted surface was evaluated after cleaning by image analysis. The residual stresses induced by grit blasting were determined by using the incremental hole drilling method and by measuring the de-flection of grit-blasted beams. Grit size was determined to be the most important influence on roughness. The average values of Ra and Rt and the percentage of grit residue increased with grit size as well as the depth of the plastic zone under the substrate. An increase of the pressure slightly increased the values of Äa and Rt but also promoted grit breakdown and grit residue. A blasting time of 3 to 6 s was sufficient to obtain the highest roughness and limit the grit breakdown. The residual stresses generated under the blasted surface were compressive, and the depth of the affected zone depended on the grit diameter, the blasting pressure, and the Young’s modulus of the substrate. More-over, the maximum residual stress was reached at the limit of the plastic zone (i.e., several tenths of a mil-limeter below the substrate surface).

  13. Biologic response to complex blast waves

    SciTech Connect

    Richmond, D.R.; Yelverton, J.T.; Fletcher, E.R.; Phillips, Y.Y.

    1985-01-01

    Small, bare charges were detonated inside an M59 armored personnel carrier (APC) in an attempt to simulate the complex blast waves generated by the jets from shaped-charge warheads penetrating into armored vehicles. Anesthetized sheep were placed inside the APC at 92- and 122-cm ranges from 57- or 113-g pentolite charges. Pressure-time was measured by pressure transducers either mounted on the animals or free standing at comparable ranges on the opposite side of the vehicle. In general, the waveforms were characterized by an initial shock wave of less than 1-msec duration followed by repeated reflections of decreasing magnitude. No deaths nor lung hemorrhages were observed, but all the animals sustained severe ear injury. Animals subjected to peak overpressures of 1.2 to 2.3 bar from the 113-g explosions also received slight non-auditory blast injuries to the upper respiratory and gastrointestinal tracts; those exposed to peak overpressures of just under 1 bar from the 57-g charges did not. The non-auditory blast injuries inside the APC were more severe than those sustained by sheep at comparable distances from 113-g charges in the open. The results suggested that the biological consequences of a complex wave of the type encountered in this study can be equated approximately to a Friedlander wave with a peak overpressure equal to that of the complex wave and with a total impulse equal to the impulse over the first 2 to 3 msec of the complex wave. 9 refs., 7 figs., 1 tab.

  14. Multiphase-flow numerical modeling of the 18 May 1980 lateral blast at Mount St. Helens, USA

    USGS Publications Warehouse

    Ongaro, T.E.; Widiwijayanti, C.; Clarke, A.B.; Voight, B.; Neri, A.

    2011-01-01

    Volcanic lateral blasts are among the most spectacular and devastating of natural phenomena, but their dynamics are still poorly understood. Here we investigate the best documented and most controversial blast at Mount St. Helens (Washington State, United States), on 18 May 1980. By means of three-dimensional multiphase numerical simulations we demonstrate that the blast front propagation, fi nal runout, and damage can be explained by the emplacement of an unsteady, stratifi ed pyroclastic density current, controlled by gravity and terrain morphology. Such an interpretation is quantitatively supported by large-scale observations at Mount St. Helens and will infl uence the defi nition and predictive mapping of hazards on blast-dangerous volcanoes worldwide. ?? 2011 Geological Society of America.

  15. Drill and Blast Tunneling Practices

    Microsoft Academic Search

    Gerhard Girmscheid; Cliff Schexnayder

    2002-01-01

    High-performance drill and blast methods for tunnel construction require that each of the individual working elements that constitute the construction process are optimized and considered as a system of sequential and parallel activities. The advantage of integrating the logistic backup systems facilitates an increase in performance. To achieve increased production, it is necessary to improve the drilling, explosive loading, temporary

  16. Rice blast disease in Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is an important agricultural commodity in Texas, with an economic impact of more than $1 billion annually. Rice blast, caused by Magnaporthe oryzae, is one of the most devastating diseases in rice. Texas Rice Belt provides a warm, humid climate favorable for the infection and reproduction of M....

  17. Transport phenomena in nanoporous materials.

    PubMed

    Kärger, Jörg

    2015-01-12

    Diffusion, that is, the irregular movement of atoms and molecules, is a universal phenomenon of mass transfer occurring in all states of matter. It is of equal importance for fundamental research and technological applications. The present review deals with the challenges of the reliable observation of these phenomena in nanoporous materials. Starting with a survey of the different variants of diffusion measurement, it highlights the potentials of "microscopic" techniques, notably the pulsed field gradient (PFG) technique of NMR and the techniques of microimaging by interference microscopy (IFM) and IR microscopy (IRM). Considering ensembles of guest molecules, these techniques are able to directly record mass transfer phenomena over distances of typically micrometers. Their concerted application has given rise to the clarification of long-standing discrepancies, notably between microscopic equilibrium and macroscopic non-equilibrium measurements, and to a wealth of new information about molecular transport under confinement, hitherto often inaccessible and sometimes even unimaginable. PMID:25123096

  18. Science and Paranormal Phenomena

    E-print Network

    Noyes, H P

    1999-01-01

    In order to ground my approach to the study of paranormal phenomena, I first explain my operational approach to physics, and to the ``historical'' sciences of cosmic, biological, human, social and political evolution. I then indicate why I believe that ``paranormal phenomena'' might --- but need not --- fit into this framework. I endorse the need for a new theoretical framework for the investigation of this field presented by Etter and Shoup at this meeting. I close with a short discussion of Ted Bastin's contention that paranormal phenomena should be {\\it defined} as contradicting physics.

  19. Science and Paranormal Phenomena

    E-print Network

    H. Pierre Noyes

    1999-06-03

    In order to ground my approach to the study of paranormal phenomena, I first explain my operational approach to physics, and to the ``historical'' sciences of cosmic, biological, human, social and political evolution. I then indicate why I believe that ``paranormal phenomena'' might --- but need not --- fit into this framework. I endorse the need for a new theoretical framework for the investigation of this field presented by Etter and Shoup at this meeting. I close with a short discussion of Ted Bastin's contention that paranormal phenomena should be {\\it defined} as contradicting physics.

  20. Science and Paranormal Phenomena

    SciTech Connect

    Noyes, H. Pierre

    1999-06-03

    In order to ground my approach to the study of paranormal phenomena, I first explain my operational approach to physics, and to the ''historical'' sciences of cosmic, biological, human, social and political evolution. I then indicate why I believe that ''paranormal phenomena'' might-but need not- fit into this framework. I endorse the need for a new theoretical framework for the investigation of this field presented by Etter and Shoup at this meeting. I close with a short discussion of Ted Bastin's contention that paranormal phenomena should be defined as contradicting physics.

  1. Explanation of Current Crowding Phenomena Induced by Impact Ionization in Advanced Si Bipolar Transistors by Means of Electrical Measurements and Light Emission Microscopy

    Microsoft Academic Search

    Paolo Pavan; Loris Vendrame; Stefano Bigliardi; Arlette Marty; Alain Chantre; Enrico Zanoni

    1992-01-01

    This paper analyzes impact ionization phenomena in advanced polysilicon emitter bipolar transistors. Two intrinsic limitations affecting multiplication coefficient at high electric fields are discussed. Emission microscopy is adopted to directly investigate and observe current crowding effects at the basis of the first kind of instability, which takes place when the device is driven at constant emitter current IE. The second

  2. Littoral blasts: Pumice-water heat transfer and the conditions for steam explosions when pyroclastic flows enter the ocean

    Microsoft Academic Search

    J. Dufek; M. Manga; M. Staedter

    2007-01-01

    Steam explosions, or littoral blasts, generated when pyroclastic flows interact with seawater may be a common, although rarely documented, phenomena. The development of steam explosions rather than passive steam production is related to the rate of thermal energy transfer from hot pyroclasts to water. We conduct a series of laboratory experiments to quantify the heat transfer and steam production rates

  3. Comparison of Blast-Induced Damage Between Presplit and Smooth Blasting of High Rock Slope

    NASA Astrophysics Data System (ADS)

    Hu, Yingguo; Lu, Wenbo; Chen, Ming; Yan, Peng; Yang, Jianhua

    2014-07-01

    This paper focuses on the comparison of damage induced by smooth blasting and presplit blasting based on the excavation of high rock slope. The whole damage process of the smooth blasting and presplit blasting excavation method is studied by using a cumulative blasting damage numerical simulation technology based on the secondary development of the dynamic finite element code LS-DYNA. The results demonstrate that, in the case of contour blasting with the method of smooth blasting, the total damage of rock slope is a result of cumulated damage induced by the production hole, buffering hole, and smooth hole. Among the total damage, the blasting of the production hole is the main resource, followed by the smooth and buffering holes. For the presplit blasting, the final damage of rock slope is mainly induced by presplit blasting itself. The spatial distribution characteristics of the final damage zone of two methods are compared. Two classes of damage zone could be found in smooth blasting excavation; one of them is the columnar high-degree damage zone around the slope surface and the other is the low-degree damage zone located in the middle of the slope. But in the case of presplit blasting, there is only the columnar high-degree damage zone around the slope surface. Finally, a damage control suggestion for two blasting excavation methods is proposed and verified based on the excavation of the temporary shiplock slopes of the Three Gorges Project in China.

  4. Viscoelastic Materials Study for the Mitigation of Blast-Related Brain Injury

    NASA Astrophysics Data System (ADS)

    Bartyczak, Susan; Mock, Willis, Jr.

    2011-06-01

    Recent preliminary research into the causes of blast-related brain injury indicates that exposure to blast pressures, such as from IED detonation or multiple firings of a weapon, causes damage to brain tissue resulting in Traumatic Brain Injury (TBI) and Post Traumatic Stress Disorder (PTSD). Current combat helmets are not sufficient to protect the warfighter from this danger and the effects are debilitating, costly, and long-lasting. Commercially available viscoelastic materials, designed to dampen vibration caused by shock waves, might be useful as helmet liners to dampen blast waves. The objective of this research is to develop an experimental technique to test these commercially available materials when subject to blast waves and evaluate their blast mitigating behavior. A 40-mm-bore gas gun is being used as a shock tube to generate blast waves (ranging from 1 to 500 psi) in a test fixture at the gun muzzle. A fast opening valve is used to release nitrogen gas from the breech to impact instrumented targets. The targets consist of aluminum/ viscoelastic polymer/ aluminum materials. Blast attenuation is determined through the measurement of pressure and accelerometer data in front of and behind the target. The experimental technique, calibration and checkout procedures, and results will be presented.

  5. Measurement of the electric form factor of the neutron at low momentum transfers using a vector polarized deuterium gas target at BLAST

    E-print Network

    Ziskin, Vitaliy

    2005-01-01

    Elastic form factors are fundamental quantities that characterize the electromagnetic structure of the nucleon. High precision measurements of these quantities are essential in understanding the structure of hadronic matter. ...

  6. Surface assessment and modification of concrete using abrasive blasting

    NASA Astrophysics Data System (ADS)

    Millman, Lauren R.

    Composite systems are applied to concrete substrates to strengthen and extend the service life. Successful restoration or rehabilitation requires surface preparation prior to the application of the overlay. Surface coatings, waterproofing systems, and other external surface applications also require surface preparation prior to application. Abrasive blast media is often used to clean and uniformly roughen the substrate. The appropriate surface roughness is necessary to facilitate a strong bond between the existing substrate and overlay. Thus, surface modification using abrasive blast media (sand and dry ice), their respective environmental effects, surface roughness characterization prior to and after blasting, and the adhesion between the substrate and overlay are the focus of this dissertation. This dissertation is comprised of an introduction, a literature review, and four chapters, the first of which addresses the environmental effects due to abrasive blasting using sand, water, and dry ice. The assessment considered four response variables: carbon dioxide (CO2) emissions, fuel and energy consumption, and project duration. The results indicated that for sand blasting and water jetting, the primary factor contributing to environmental detriment was CO22 emissions from vehicular traffic near the construction site. The second chapter is an analysis of the International Concrete Repair Institute's (ICRI) concrete surface profiles (CSPs) using 3-D optical profilometry. The primary objective was to evaluate the suitability of approximating the 3-D surface (areal) parameters with those extracted from 2-D (linear) profiles. Four profile directions were considered: two diagonals, and lines parallel and transverse to the longitudinal direction of the mold. For any CSP mold, the estimation of the 3-D surface roughness using a 2-D linear profile resulted in underestimation and overestimation errors exceeding 50%, demonstrating the inadequacy of 2-D linear profiles to approximate the 3-D concrete surface profiles. The errors were reduced when a weighted average of the four linear profiles approximated the corresponding 3-D parameter. The following chapter considers the parametric and sensitivity of concrete surface topography measurements. The weighted average of the four 2-D profiles consistently resulted in underestimation of the corresponding 3-D parameters: the dispersion of surface elevations (Sq) and the roughness (Sa). Results indicated the 3-D parameter, Sq, had the least sensitivity to data point reduction. The final chapter investigated surface modification using dry ice and sand blasting. The overall objective was to evaluate the change in the 3-D surface roughness (Sa) following blasting as functions of mix design and as induced by freeze-thaw cycling, and to compare the results obtained using dry ice with those obtained using sand as the blasting media. In general, sand blasting produced larger changes in Sa compared to dry ice blasting for the concrete mix designs considered. The primary mechanism responsible for altering the surface topography of the concrete was the scaling of the superficial cement paste layer on the exposed surface, which was due to freeze-thaw cycling. The largest relative change in roughness following blasting occurred in the control samples, which had not undergone freeze-thaw cycling.

  7. The Balloon-borne Large Aperture Submillimeter Telescope: BLAST

    E-print Network

    E. Pascale; P. A. R. Ade; J. J. Bock; E. L. Chapin; J. Chung; M. J. Devlin; S Dicker; M. Griffin; J. O. Gundersen; M. Halpern; P. C. Hargrave; D. H. Hughes; J. Klein; C. J. MacTavish; G. Marsden; P. G. Martin; T. G. Martin; P. Mauskopf; C. B. Netterfield; L. Olmi; G. Patanchon; M. Rex; D. Scott; C. Semisch; N. Thomas; M. D. P. Truch; C. Tucker; G. S. Tucker; M. P. Viero; D. V. Wiebe

    2008-03-27

    The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) is a sub-orbital surveying experiment designed to study the evolutionary history and processes of star formation in local galaxies (including the Milky Way) and galaxies at cosmological distances. The BLAST continuum camera, which consists of 270 detectors distributed between 3 arrays, observes simultaneously in broad-band (30%) spectral-windows at 250, 350, and 500 microns. The optical design is based on a 2m diameter telescope, providing a diffraction-limited resolution of 30" at 250 microns. The gondola pointing system enables raster mapping of arbitrary geometry, with a repeatable positional accuracy of ~30"; post-flight pointing reconstruction to ~5" rms is achieved. The on-board telescope control software permits autonomous execution of a pre-selected set of maps, with the option of manual override. In this paper we describe the primary characteristics and measured in-flight performance of BLAST. BLAST performed a test-flight in 2003 and has since made two scientifically productive long-duration balloon flights: a 100-hour flight from ESRANGE (Kiruna), Sweden to Victoria Island, northern Canada in June 2005; and a 250-hour, circumpolar-flight from McMurdo Station, Antarctica, in December 2006.

  8. 30 CFR 57.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...explosive materials or initiating systems are brought to the blast site, the blast site shall be attended; barricaded and posted with warning...loading begins, the only activities permitted within the blast site shall be those activities directly...

  9. 30 CFR 56.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...explosive materials or initiating systems are brought to the blast site, the blast site shall be attended; barricaded and posted with warning...loading begins, the only activities permitted within the blast site shall be those activities directly...

  10. Nondestructive thermoelectric evaluation of the grit blasting induced effects in metallic biomaterials

    NASA Astrophysics Data System (ADS)

    Carreon, H.; Ruiz, A.; Barriuso, S.; González-Carrasco, J. L.; Caballero, F. G.; Lieblich, M.

    2013-01-01

    Grit blasting is a surface treatment process widely used to enhance mechanical fixation of the implants through increasing their roughness. Test samples of two metallic biomaterial alloys such 316LVM and Ti6Al4V were blasted by projecting Al2O3 and ZrO2 particles which yield a coarse and a fine rough surface. Then, the blasted samples were thermally treated before and after partial stress relaxation and measured by non-destructive thermoelectric techniques (NDTT), the non-contacting and contacting thermoelectric power (TEP) measurements respectively. It has been found that the TEP measurements are associated directly with the subtle material variations such as cold work and compressive residual stresses due to plastic deformation produced by grit blasting. The TEP measurements clearly demonstrate that the non-contact NDTT technique is very sensitive to the reverse transformation of the ?'-martensite (blasted 316LVM) and the expected relaxation of compressive residual stresses with increasing the severity of the thermal treatment (blasted 316LVM and Ti-6Al-4V), while the contact NDTT results are closely related to grain size refinement and work hardening.

  11. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    William S. McPhee

    2001-08-31

    The Department of Energy (DOE) needs improved technologies to decontaminate large areas of both concrete and steel surfaces. The technology should have high operational efficiency, minimize exposures to workers, and produce low levels of secondary waste. In order to meet the DOE's needs, an applied research and development project for the improvement of a current decontamination technology, Vacuum Blasting, is proposed. The objective of this project is to improve the productivity and lower the expense of the existing vacuum blasting technology which has been widely used in DOE sites for removing radioactive contamination, PCBs, and lead-based paint. The proposed work would increase the productivity rate and provide safe and cost-effective decontamination of the DOE sites.

  12. Photographs of Blast Effects on Structures

    NSDL National Science Digital Library

    Christopher Griffith

    This photograph collection shows a wood-frame house located 1,100 meters from ground zero, exposed to a nuclear blast at the Nevada Test Site. The test was Upshot-Knothole Annie, a 16 Kt tower shot, on March 17, 1953. Exposure to thermal radiation was 25 cal/cm2, about one-quarter of that experienced at ground zero in Hiroshima. The blast over pressure was 5 psi, and the blast wave created surface winds of 160 mph.

  13. Blast monitoring instrumentation and analysis techniques, with an emphasis on field applications

    Microsoft Academic Search

    R. Frank Chiappetta

    1998-01-01

    Detailed monitoring on hundreds of single hole and multi-row blasts in full scale varying blast environments were completed for specific analyses using high-speed photography and\\/or videography, laser surveying, refraction seismographs, digital seismographs to measure ground vibration\\/airblast, fragmentation and jointing analysis systems, borehole inspection cameras, multi-channel recorders and continuous VOD instrumentation. The majority of field tests were instrumented with multi-instrumentation systems

  14. Simulation of the Reflected Blast Wave froma C-4 Charge

    SciTech Connect

    Howard, W M; Kuhl, A L; Tringe, J W

    2011-08-01

    The reflection of a blast wave from a C4 charge detonated above a planar surface is simulated with our ALE3D code. We used a finely-resolved, fixed Eulerian 2-D mesh (167 {micro}m per cell) to capture the detonation of the charge, the blast wave propagation in nitrogen, and its reflection from the surface. The thermodynamic properties of the detonation products and nitrogen were specified by the Cheetah code. A programmed-burn model was used to detonate the charge at a rate based on measured detonation velocities. Computed pressure histories are compared with pressures measured by Kistler 603B piezoelectric gauges at 8 ranges (GR = 0, 2, 4, 8, 10, and 12 inches) along the reflecting surface. Computed and measured waveforms and positive-phase impulses were similar, except at close-in ranges (GR < 2 inches), which were dominated by jetting effects.

  15. Hidden Threshold Phenomena for Fixed-Density SAT-formulae

    Microsoft Academic Search

    Hans Van Maaren; Linda Van Norden

    2003-01-01

    Experimental evidence is presented that hidden threshold phenomena exist for fixed density random 3-SAT formulae. At such fixed densities the (sub-optimal) average Horn fraction (computed with a spe- cially designed algorithm) appears to be a parameter with respect to which these phenomena can be measured. This paper investigates the eects of density and size on the observed phenomena.

  16. The Next Generation BLAST Experiment

    E-print Network

    Galitzki, Nicholas; Angilè, Francesco E; Ashton, Peter; Beall, James A; Becker, Dan; Bradford, Kristi J; Che, George; Cho, Hsiao-Mei; Devlin, Mark J; Dober, Bradley J; Fissel, Laura M; Fukui, Yasuo; Gao, Jiansong; Groppi, Christopher E; Hillbrand, Seth; Hilton, Gene C; Hubmayr, Johannes; Irwin, Kent D; Klein, Jeffrey; Van Lanen, Jeff; Li, Dale; Li, Zhi-Yun; Lourie, Nathan P; Mani, Hamdi; Martin, Peter G; Mauskopf, Philip; Nakamura, Fumitaka; Novak, Giles; Pappas, David P; Pascale, Enzo; Pisano, Giampaolo; Santos, Fabio P; Savini, Giorgio; Scott, Douglas; Stanchfield, Sara; Tucker, Carole; Ullom, Joel N; Underhill, Matthew; Vissers, Michael R; Ward-Thompson, Derek

    2014-01-01

    The Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol) was a suborbital experiment designed to map magnetic fields in order to study their role in star formation processes. BLASTPol made detailed polarization maps of a number of molecular clouds during its successful flights from Antarctica in 2010 and 2012. We present the next-generation BLASTPol instrument (BLAST-TNG) that will build off the success of the previous experiment and continue its role as a unique instrument and a test bed for new technologies. With a 16-fold increase in mapping speed, BLAST-TNG will make larger and deeper maps. Major improvements include a 2.5 m carbon fiber mirror that is 40% wider than the BLASTPol mirror and ~3000 polarization sensitive detectors. BLAST-TNG will observe in three bands at 250, 350, and 500 microns. The telescope will serve as a pathfinder project for microwave kinetic inductance detector (MKID) technology, as applied to feedhorn coupled submillimeter detector arrays. The liquid he...

  17. Quarter-scale close-in blast-loading experiments in support of the planned contained firing facility

    SciTech Connect

    Pastrnak, J.W.; Baker, C.F.; Simmons, L.F.

    1994-07-27

    In anticipation of increasingly stringent environmental regulations, Lawrence Livermore National Laboratory is proposing to construct a 60-kg firing chamber to provide blast-effects containment for most of its open-air, high-explosive, firing operations. Even though the Laboratory`s operations are within current environmental limits, containment of the blast effects and hazardous debris will drastically reduce emissions to the environment and minimize the generated hazardous waste. One of the main design considerations is the extremely close-in (Z = 0.66 ft/lb{sup l/3}) blast loading on the reinforced concrete ff the chamber. Historically, floor damage due to close-in loading has been a common problem for other blast chambers within the US Department of Energy and Department of Defense (DOE/DoD). Blast-effects testing and computer analysis were conducted on a replica quarter-scale model of the preliminary floor design. Nineteen blast tests ranging from scaled distances of 1.14 ft/lb{sup l/3} (25%) to 0.57ft/lb{sup 1/3} (200%) were performed on the strain-gaged floor model. In response to predicted and measured failures at the 25% level, various state-of-the-art blast attenuation systems were quickly developed and tested. The most effective blast-attenuation system provided a significant improvement by reducing the measured floor stresses to acceptable levels while minimizing, by its reusability, the impact on the environment.

  18. Study of blast event propagation in different media using a novel ultrafast miniature optical pressure sensor

    NASA Astrophysics Data System (ADS)

    Zou, Xiaotian; Wu, Nan; Tian, Ye; Zhang, Hongtao; Niezrecki, Christopher; Wang, Xingwei

    2011-06-01

    Traumatic brain injury (TBI, also called intracranial injury) is a high potential threat to our soldiers. A helmet structural health monitoring system can be effectively used to study the effects of ballistic/blast events on the helmet and human skull to prevent soldiers from TBI. However, one of the biggest challenges lies in that the pressure sensor installed inside the helmet system must be fast enough to capture the blast wave during the transient period. In this paper, an ultrafast optical fiber sensor is presented to measure the blast signal. The sensor is based on a Fabry-Pérot (FP) interferometeric principle. An FP cavity is built between the endface of an etched optical fiber tip and the silica thin diaphragm attached on the end of a multimode optical fiber. The sensor is small enough to be installed in different locations of a helmet to measure blast pressure simultaneously. Several groups of tests regarding multi-layer blast events were conducted to evaluate the sensors' performance. The sensors were mounted in different segments of a shock tube side by side with the reference sensors, to measure a rapidly increasing pressure. The segments of the shock tube were filled with different media. The results demonstrated that our sensors' responses agreed well with those from the electrical reference sensors. In addition, the home-made shock tube could provide a good resource to study the propagation of blast event in different media.

  19. Ion exchange phenomena

    SciTech Connect

    Bourg, I.C.; Sposito, G.

    2011-05-01

    Ion exchange phenomena involve the population of readily exchangeable ions, the subset of adsorbed solutes that balance the intrinsic surface charge and can be readily replaced by major background electrolyte ions (Sposito, 2008). These phenomena have occupied a central place in soil chemistry research since Way (1850) first showed that potassium uptake by soils resulted in the release of an equal quantity of moles of charge of calcium and magnesium. Ion exchange phenomena are now routinely modeled in studies of soil formation (White et al., 2005), soil reclamation (Kopittke et al., 2006), soil fertilitization (Agbenin and Yakubu, 2006), colloidal dispersion/flocculation (Charlet and Tournassat, 2005), the mechanics of argillaceous media (Gajo and Loret, 2007), aquitard pore water chemistry (Tournassat et al., 2008), and groundwater (Timms and Hendry, 2007; McNab et al., 2009) and contaminant hydrology (Chatterjee et al., 2008; van Oploo et al., 2008; Serrano et al., 2009).

  20. Dynamic phenomena in sunspots

    NASA Technical Reports Server (NTRS)

    Moore, R. L.

    1981-01-01

    A detailed summary of observed dynamic phenomena associated with sunspots is presented, together with a description of the observational techniques and available analytical formulations for the processes under study. The phenomena detected thus far are grouped into aperiodic events and oscillations and waves. Aperiodic phenomena comprise umbral flares, the superpenumbra, and inverse Evershed flow. Internal, aperiodic manifestations include penumbral grains, the photospheric penumbral dark fibrils, Evershed flow, umbral dots, the inhomogeneity of the umbral magnetic field, and umbral turbulence. Oscillations and flashes are seen in the umbra, while running waves and dark puffs have been detected in the penumbra, and oscillations are located in the photosphere. All the observed features are evidence of mass motion and change on time scales of less than an hour.

  1. Blast dynamics at Mount St Helens on 18 May 1980

    USGS Publications Warehouse

    Kieffer, S.W.

    1981-01-01

    At 8.32 a.m. on 18 May 1980, failure of the upper part of the north slope of Mount St Helens triggered a lateral eruption ('the blast') that devastated the conifer forests in a sector covering ???500 km2 north of the volcano. I present here a steady flow model for the blast dynamics and propose that through much of the devastated area the blast was a supersonic flow of a complex multiphase (solid, liquid, vapour) mixture. The shape of the blast zone; pressure, temperature, velocity (Mach number) and density distributions within the flow; positions of weak and strong internal shocks; and mass flux, energy flux, and total energy are calculated. The shape of blast zone was determined by the initial areal expansion from the reservoir, by internal expansion and compression waves (including shocks), and by the density of the expanding mixture. The pressure within the flow dropped rapidly away from the source of the blast until, at a distance of ???11 km, the flow became underpressured relative to the surrounding atmosphere. Weak shocks within the flow subparallel to the east and west margins coalesced at about this distance into a strong Mach disk shock, across which the flow velocities would have dropped from supersonic to subsonic as the pressure rose back towards ambient. The positions of the shocks may be reflected in differences in the patterns of felled trees. At the limits of the devastated area, the temperature had dropped only 20% from the reservoir temperature because the entrained solids thermally buffered the flow (the dynamic and thermodynamic effects of the admixture of the surrounding atmosphere and the uprooted forest and soils into the flow are not considered). The density of the flow decreased with distance until, at the limits of the blast zone, 20-25 km from the volcano, the density became comparable with that of the surrounding (dirty) atmosphere and the flow became buoyant and ramped up into the atmosphere. According to the model, the mass flux per unit area at the source was 0.6 ?? 104 g s-1 cm-2 and the energy flux per unit area was 2.5 MW cm-2. From the measured total ejected mass, 0.25 ?? 1015 g, the total energy released during the eruption was 1024 erg or 24 megatons. The model, triggering of the eruption and the transition from unsteady to steady flow, and applications to eyewitness observations and atmospheric effects are discussed in ref. 1. ?? 1981 Nature Publishing Group.

  2. Flow phenomena in turbomachines

    NASA Astrophysics Data System (ADS)

    Creitzer, E. M.; Epstein, A. H.; Giles, M. B.; McCune, J. E.; Tan, C. S.

    1993-01-01

    This report describes work carried out at the Gas Turbine Laboratory at MIT during the period 10/20/89 - 10/19/92, as part of our multi-investigator effort on basic unsteady flow phenomena in turbomachines. Within the overall project four separate tasks are specified. These are, in brief: (1) The Influence of Inlet Temperature Nonuniformities on Turbine Heat Transfer and Dynamics; (2) Assessment of Unsteady Losses in Stator/ Rotor Interactions; (3) Unsteady Phenomena and Flowfield instabilities in Multistage Axial Compressors; (4) Vortex Wake-Compressor Blade Interaction in Cascades - A New Rapid Method for Unsteady Separation and Vorticity Flux Calculations.

  3. Imaging of snapping phenomena

    PubMed Central

    Guillin, R; Marchand, A J; Roux, A; Niederberger, E; Duvauferrier, R

    2012-01-01

    Snapping phenomena result from the sudden impingement between anatomical and/or heterotopical structures with subsequent abrupt movement and noise. Snaps are variously perceived by patients, from mild discomfort to significant pain requiring surgical management. Identifying the precise cause of snaps may be challenging when no abnormality is encountered on routinely performed static examinations. In this regard, dynamic imaging techniques have been developed over time, with various degrees of success. This review encompasses the main features of each imaging technique and proposes an overview of the main snapping phenomena in the musculoskeletal system. PMID:22744321

  4. ScalaBLAST 2.0: Rapid and robust BLAST calculations on multiprocessor systems

    SciTech Connect

    Oehmen, Christopher S.; Baxter, Douglas J.

    2013-03-15

    BLAST remains one of the most widely used tools in computational biology. The rate at which new sequence data is available continues to grow exponentially, driving the emergence of new fields of biological research. At the same time multicore systems and conventional clusters are more accessible. ScalaBLAST has been designed to run on conventional multiprocessor systems with an eye to extreme parallelism, enabling parallel BLAST calculations using over 16,000 processing cores with a portable, robust, fault-resilient design. ScalaBLAST 2.0 source code can be freely downloaded from http://omics.pnl.gov/software/ScalaBLAST.php.

  5. Serum-Based Protein Biomarkers in Blast-Induced Traumatic Brain Injury Spectrum Disorder

    PubMed Central

    Agoston, Denes V.; Elsayed, Mohammad

    2012-01-01

    The biological consequences of exposure to explosive blast are extremely complex. Serum protein biomarkers in blast-induced traumatic brain injury (bTBI) can aid in determining injury severity, monitoring progress, and predicting outcome. Exposure to blast results in varying degrees of physical injury. Explosive blast can also induce psychological stress that can contribute to or amplify the extent of physical damage. Given the complexity, scale of injury, and variety of symptoms, bTBI may be best described as a spectrum disorder. In this focused review, we summarize the status of serum protein biomarkers in bTBI in the context of the classification and pathological changes of other forms of TBI. Finally, we recommend specific and easily implementable measures to accelerate serum protein biomarker discovery and validation in bTBI. PMID:22783223

  6. Energy conversion in a glass-laser-induced blast wave in air

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Komurasaki, Kimiya; Yamaguchi, Toshikazu; Shimamura, Kohei; Arakawa, Yoshihiro

    2010-12-01

    Near-infrared solid laser-induced blast waves were investigated using a Q-switched Nd:glass laser oscillating at 1053 nm wavelength, up to 2.0 J/pulse laser energy Ei, and 33 ns pulse duration (full width at half maximum). Half-shadowgraph half-self-emission visualization elucidated laser detonation waves and blast waves. Laser output and transmission through the waves were measured using pairs of a photodetectors and energy meters. Results show volumetric absorption in this near-infrared region, which is mainly attributable to low inverse-Bremsstrahlung absorption coefficients at short wavelengths. Some input laser energy was converted into blast wave energy: 59% at Ei=1.0 J/pulse, which approximates that of CO2 laser-induced blast waves.

  7. [The characteristics of blast traumatic brain injury].

    PubMed

    Matsumoto, Yoshihisa; Hatano, Ben; Matsushita, Yoshitaro; Nawashiro, Hiroshi; Shima, Katsuji

    2010-08-01

    With the increase in terrorist activity in recent times, the number of blast injuries has also increased in civilian and military settings. In a recent war, the number of patients who suffered blast traumatic brain injury (bTBI) increased, so treatment of bTBI is currently a very important issue. Blast injury is complicated and can be divided into 4 categories: primary, secondary, tertiary, and quaternary. Primary blast injury results from exposure to blast waves; secondary blast injury is trauma caused by fragments of explosive devices; tertiary blast injury is the result of collision with objects; and quaternary blast injury is the result of exposure to toxic and other substances. Blast waves mainly injure air-containing organs such as the lung, bowel, and ear. The brain may also be affected by blast waves. From the clinical perspective, hyperemia and severe cerebral edema occur frequently in patients who sustain significant bTBI. Penetrating or closed head injury caused by the explosion may be associated with vasospasm and pseudoaneurysm formation. Mild traumatic brain injury during war can be associated with posttraumatic stress disorder. To elucidate the mechanism of bTBI, many research works using animal models and computer analysis are underway. Such studies have so far shown that blast waves can cause damage to the brain tissue and cognitive deficits; however, detailed investigations on this topic are still required. Treatment of bTBI patients may require clinical knowledge and skills related to intensive care, neurology, and neurosurgery. Moreover, further research is required in this field. PMID:20697143

  8. Concussive brain injury from explosive blast

    PubMed Central

    de Lanerolle, Nihal C; Hamid, Hamada; Kulas, Joseph; Pan, Jullie W; Czlapinski, Rebecca; Rinaldi, Anthony; Ling, Geoffrey; Bandak, Faris A; Hetherington, Hoby P

    2014-01-01

    Objective Explosive blast mild traumatic brain injury (mTBI) is associated with a variety of symptoms including memory impairment and posttraumatic stress disorder (PTSD). Explosive shock waves can cause hippocampal injury in a large animal model. We recently reported a method for detecting brain injury in soldiers with explosive blast mTBI using magnetic resonance spectroscopic imaging (MRSI). This method is applied in the study of veterans exposed to blast. Methods The hippocampus of 25 veterans with explosive blast mTBI, 20 controls, and 12 subjects with PTSD but without exposure to explosive blast were studied using MRSI at 7 Tesla. Psychiatric and cognitive assessments were administered to characterize the neuropsychiatric deficits and compare with findings from MRSI. Results Significant reductions in the ratio of N-acetyl aspartate to choline (NAA/Ch) and N-acetyl aspartate to creatine (NAA/Cr) (P < 0.05) were found in the anterior portions of the hippocampus with explosive blast mTBI in comparison to control subjects and were more pronounced in the right hippocampus, which was 15% smaller in volume (P < 0.05). Decreased NAA/Ch and NAA/Cr were not influenced by comorbidities – PTSD, depression, or anxiety. Subjects with PTSD without blast had lesser injury, which tended to be in the posterior hippocampus. Explosive blast mTBI subjects had a reduction in visual memory compared to PTSD without blast. Interpretation The region of the hippocampus injured differentiates explosive blast mTBI from PTSD. MRSI is quite sensitive in detecting and localizing regions of neuronal injury from explosive blast associated with memory impairment. PMID:25493283

  9. Reactive Blast Waves from Composite Charges

    SciTech Connect

    Kuhl, A L; Bell, J B; Beckner, V E

    2009-10-16

    Investigated here is the performance of composite explosives - measured in terms of the blast wave they drive into the surrounding environment. The composite charge configuration studied here was a spherical booster (1/3 charge mass), surrounded by aluminum (Al) powder (2/3 charge mass) at an initial density of {rho}{sub 0} = 0.604 g/cc. The Al powder acts as a fuel but does not detonate - thereby providing an extreme example of a 'non-ideal' explosive (where 2/3 of the charge does not detonate). Detonation of the booster charge creates a blast wave that disperses the Al powder and ignites the ensuing Al-air mixture - thereby forming a two-phase combustion cloud embedded in the explosion. Afterburning of the booster detonation products with air also enhances and promotes the Al-air combustion process. Pressure waves from such reactive blast waves have been measured in bomb calorimeter experiments. Here we describe numerical simulations of those experiments. A Heterogeneous Continuum Model was used to model the dispersion and combustion of the Al particle cloud. It combines the gasdynamic conservation laws for the gas phase with a dilute continuum model for the dispersed phase, as formulated by Nigmatulin. Inter-phase mass, momentum and energy exchange are prescribed by phenomenological models of Khasainov. It incorporates a combustion model based on mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gasdynamic fields, along with a model for mass transfer from the particle phase to the gas. The model takes into account both the afterburning of the detonation products of the booster with air, and the combustion of the Al particles with air. The model equations were integrated by high-order Godunov schemes for both the gas and particle phases. Adaptive Mesh Refinement (AMR) was used to capture the energy-bearing scales of the turbulent flow on the computational grid, and to track/resolve reaction zones. Numerical simulations of the explosion fields from 1.5-g and 10-kg composite charges were performed. Computed pressure histories (red curve) are compared with measured waveforms (black curves) in Fig. 1. Comparison of these results with a waveform for a non-combustion case in nitrogen (blue curve) demonstrates that a reactive blast wave was formed. Cross-sectional views of the temperature field at various times are presented in Fig. 2, which shows that the flow is turbulent. Initially, combustion occurs at the fuel-air interface, and the energy release rate is controlled by the rate of turbulent mixing. Eventually, oxidizer becomes distributed throughout the cloud via ballistic mixing of the particles with air; energy release then occurs in a distributed combustion mode, and Al particle kinetics controls the energy release rate. Details of the Heterogeneous Continuum Model and results of the numerical simulations of composite charge explosions will be described in the paper.

  10. Neutron Star Phenomena

    NASA Technical Reports Server (NTRS)

    Ruderman, Malvin

    1998-01-01

    Various phenomena involving neutron stars are addressed. Electron-positron production in the near magnetosphere of gamma-ray pulsars is discussed along with magnetic field evolution in spun-up and spinning-down pulsars. Glitches and gamma-ray central engines are also discussed.

  11. Solar cosmic ray phenomena

    Microsoft Academic Search

    K. G. McCracken; U. R. Rao

    1970-01-01

    This review attempts to present an integrated view of the several types of solar cosmic ray phenomena. The relevant large and small scale properties of the interplanetary medium are first surveyed, and their use in the development of a quantitative understanding of the cosmic ray propagation processes summarised. Solar cosmic ray events, in general, are classified into two phenomenological categories:

  12. Mine blast injuries: ocular and social aspects

    PubMed Central

    Muzaffar, W.; Khan, M. D.; Akbar, M; Khan, M. D.; Malik, A. M.; Durrani, O.

    2000-01-01

    BACKGROUND/AIMS—Landmines have long been used in conventional warfare. These are antipersonnel mines which continue to injure people long after a ceasefire without differentiating between friend or foe, soldier or civilian, women or children. This study focuses on Afghan non-combatants engaged in mine clearing operations in Afghanistan in the aftermath of the Russo-Afghan war. The patterns and types of injuries seen are described and experiences in their management, ways, and means to prevent them, and recommendations for the rehabilitation of the affected individuals are given.?METHODS—It is a retrospective and analytical study of 84 patients aged 19-56 years who sustained mine blast injuries during mine clearing operations in Afghanistan from November 1992 to January 1996. The study was carried out at a military hospital with tertiary care facilities. The patients were divided into three groups on the basis of their injuries. Group 1 required only general surgical attention, group 2 sustained only ocular injuries, while group 3 had combined ocular and general injuries. Patients in groups 2 and 3 were treated in two phases. The first phase aimed at immediate restoration of the anatomy, while restoration of function wherever possible was done in subsequent surgical procedures in the second phase.?RESULTS—It was observed that 51 out of 84 patients (60.7%) had sustained ocular trauma of a variable degree as a result of the blasts. The mean age of the victims was 29 years and they were all male. A total of 91 eyes of 51 patients (89.2%) had been damaged. Bilaterality of damage was seen in 40 (78.4%) patients. Most, 34 (37.3%), eyes became totally blind (NPL). Only a few escaped with injury mild enough not to impair vision. Foreign bodies, small and multiple, were found in the majority of eyes; most, however, were found in the anterior segment, and posterior segment injuries were proportionally less.?CONCLUSIONS—The prevalence of blindness caused by mine blast injuries is quite high. The resulting psychosocial trauma to the patients and their families is tremendous and has not been adequately highlighted. These injuries are a great drain on the country's resources. Enforcement of preventive measures and the use of protective gear and sophisticated equipment by the mine clearing personnel would prove to be far more economical in terms of human life as well as medical and economic resources. There is also need for greater attention towards the establishment of support groups and rehabilitation programmes for these individuals.?? PMID:10837390

  13. Fluid dynamic aspects of jet noise generation. [noise measurement of jet blast effects from supersonic jet flow in convergent-divergent nozzles

    NASA Technical Reports Server (NTRS)

    Barra, V.; Panunzio, S.

    1976-01-01

    Jet engine noise generation and noise propagation was investigated by studying supersonic nozzle flow of various nozzle configurations in an experimental test facility. The experimental facility was constructed to provide a coaxial axisymmetric jet flow of unheated air. In the test setup, an inner primary flow exhausted from a 7 in. exit diameter convergent--divergent nozzle at Mach 2, while a secondary flow had a 10 in. outside diameter and was sonic at the exit. The large dimensions of the jets permitted probes to be placed inside the jet core without significantly disturbing the flow. Static pressure fluctuations were measured for the flows. The nozzles were designed for shock free (balanced) flow at Mach 2. Data processing techniques and experimental procedures were developed in order to study induced disturbances at the edge of the supersonic flows, and the propagation of those disturbances throughout the flows. Equipment used (specifications are given) to record acoustic levels (far field noise) is described. Results and conclusions are presented and discussed. Diagrams of the jet flow fields are included along with photographs of the test stand.

  14. Are all lymphoid blasts in the cell cycle?

    Microsoft Academic Search

    G. Wiedemann; R. Pabst; T. Wagner; F. Trepel

    1988-01-01

    Summary  Labelling index after one or repeated intravenous injections of 3H-thymidine was measured for various subpopulations of lymphatic\\u000a cells in different canine lymphoid compartments and correlated with cell morphology. High doses of tritiated thymidine were\\u000a injected and exposure times of up to 211 days were used. The labelling indices of lymphoid blasts were comparable in all tissues\\u000a investigated. Labelling index varied

  15. Color changing photonic crystals detect blast exposure

    PubMed Central

    Cullen, D. Kacy; Xu, Yongan; Reneer, Dexter V.; Browne, Kevin D.; Geddes, James W.; Yang, Shu; Smith, Douglas H.

    2010-01-01

    Blast-induced traumatic brain injury (bTBI) is the “signature wound” of the current wars in Iraq and Afghanistan. However, with no objective information of relative blast exposure, warfighters with bTBI may not receive appropriate medical care and are at risk of being returned to the battlefield. Accordingly, we have created a colorimetric blast injury dosimeter (BID) that exploits material failure of photonic crystals to detect blast exposure. Appearing like a colored sticker, the BID is fabricated in photosensitive polymers via multi-beam interference lithography. Although very stable in the presence of heat, cold or physical impact, sculpted micro- and nano-structures of the BID are physically altered in a precise manner by blast exposure, resulting in color changes that correspond with blast intensity. This approach offers a lightweight, power-free sensor that can be readily interpreted by the naked eye. Importantly, with future refinement this technology may be deployed to identify soldiers exposed to blast at levels suggested to be supra-threshold for non-impact blast-induced mild TBI. PMID:21040795

  16. Highly concentrated foam formulation for blast mitigation

    DOEpatents

    Tucker, Mark D. (Albuquerque, NM); Gao, Huizhen (Albuquerque, NM)

    2010-12-14

    A highly concentrated foam formulation for blast suppression and dispersion mitigation for use in responding to a terrorism incident involving a radiological dispersion device. The foam formulation is more concentrated and more stable than the current blast suppression foam (AFC-380), which reduces the logistics burden on the user.

  17. Aspects of blast resistant masonry design

    SciTech Connect

    Volkman, D.E.

    1989-01-01

    Blast resistant design should be examined for building code incorporation, due to the potential of explosions occurring in an industrial society. Specifically, public and commercial structures of concrete masonry construction need additional building code criteria, since these buildings have high density populations to protect. Presently, blast resistant design is accomplished by using government published manuals, but these do not address industry standard construction. A design air blast load of 4.54 kg (10 lbs) of TNT, located 0.91 m (3 ft) above ground surface and 30.48 m (100 ft) from a structure should be considered standard criteria. This loading would be sufficient to protect against blast, resist progressive failure, and yet not be an economic impediment. Design details and adequate inspection must be observed to ensure blast resistant integrity. 10 refs., 3 figs., 1 tab.

  18. BLAST Autonomous Daytime Star Cameras

    E-print Network

    Marie Rex; Edward Chapin; Mark J. Devlin; Joshua Gundersen; Jeff Klein; Enzo Pascale; Donald Wiebe

    2006-05-01

    We have developed two redundant daytime star cameras to provide the fine pointing solution for the balloon-borne submillimeter telescope, BLAST. The cameras are capable of providing a reconstructed pointing solution with an absolute accuracy daytime float conditions. Each camera combines a 1 megapixel CCD with a 200 mm f/2 lens to image a 2 degree x 2.5 degree field of the sky. The instruments are autonomous. An internal computer controls the temperature, adjusts the focus, and determines a real-time pointing solution at 1 Hz. The mechanical details and flight performance of these instruments are presented.

  19. BLAST Autonomous Daytime Star Cameras

    E-print Network

    Rex, M; Devlin, M J; Gundersen, J; Klein, J; Pascale, E; Wiebe, D; Rex, Marie; Chapin, Edward; Devlin, Mark J.; Gundersen, Joshua; Klein, Jeff; Pascale, Enzo; Wiebe, Donald

    2006-01-01

    We have developed two redundant daytime star cameras to provide the fine pointing solution for the balloon-borne submillimeter telescope, BLAST. The cameras are capable of providing a reconstructed pointing solution with an absolute accuracy daytime float conditions. Each camera combines a 1 megapixel CCD with a 200 mm f/2 lens to image a 2 degree x 2.5 degree field of the sky. The instruments are autonomous. An internal computer controls the temperature, adjusts the focus, and determines a real-time pointing solution at 1 Hz. The mechanical details and flight performance of these instruments are presented.

  20. Weak Values are Interference Phenomena

    E-print Network

    Justin Dressel

    2015-02-26

    Weak values arise experimentally as conditioned averages of weak (noisy) observable measurements that minimally disturb an initial quantum state, and also as dynamical variables for reduced quantum state evolution even in the absence of measurement. These averages can exceed the eigenvalue range of the observable ostensibly being estimated, which has prompted considerable debate regarding their interpretation. Classical conditioned averages of noisy signals only show such anomalies if the quantity being measured is also disturbed prior to conditioning. This fact has recently been rediscovered, along with the question whether anomalous weak values are merely classical disturbance effects. Here we carefully review the role of the weak value as both a conditioned observable estimation and a dynamical variable, and clarify why classical disturbance models will be insufficient to explain the weak value unless they can also simulate other quantum interference phenomena.

  1. Weak values as interference phenomena

    NASA Astrophysics Data System (ADS)

    Dressel, Justin

    2015-03-01

    Weak values arise experimentally as conditioned averages of weak (noisy) observable measurements that minimally disturb an initial quantum state, and also as dynamical variables for reduced quantum state evolution even in the absence of measurement. These averages can exceed the eigenvalue range of the observable ostensibly being estimated, which has prompted considerable debate regarding their interpretation. Classical conditioned averages of noisy signals only show such anomalies if the quantity being measured is also disturbed prior to conditioning. This fact has recently been rediscovered, along with the question whether anomalous weak values are merely classical disturbance effects. Here we carefully review the role of the weak value as both a conditioned observable estimation and a dynamical variable, and clarify why classical disturbance models will be insufficient to explain the weak value unless they can also simulate other quantum interference phenomena.

  2. High resolution imaging of colliding blast waves in cluster media

    NASA Astrophysics Data System (ADS)

    Smith, Roland A.; Lazarus, James; Hohenberger, Matthias; Marocchino, Alberto; Robinson, Joseph S.; Chittenden, Jeremy P.; Moore, Alastair S.; Gumbrell, Edward T.; Dunne, Mike

    2007-12-01

    Strong shocks and blast wave collisions are commonly observed features in astrophysical objects such as nebulae and supernova remnants. Numerical simulations often underpin our understanding of these complex systems, however modelling of such extreme phenomena remains challenging, particularly so for the case of radiative or colliding shocks. This highlights the need for well-characterized laboratory experiments both to guide physical insight and to provide robust data for code benchmarking. Creating a sufficiently high-energy-density gas medium for conducting scaled laboratory astrophysics experiments has historically been problematic, but the unique ability of atomic cluster gases to efficiently couple to intense pulses of laser light now enables table top scale (1 J input energy) studies to be conducted at gas densities of >1019 particles cm-3 with an initial energy density >5 × 109 J g-1. By laser heating atomic cluster gas media we can launch strong (up to Mach 55) shocks in a range of geometries, with and without radiative precursors. These systems have been probed with a range of optical and interferometric diagnostics in order to retrieve electron density profiles and blast wave trajectories. Colliding cylindrical shock systems have also been studied, however the strongly asymmetric density profiles and radial and longitudinal mass flow that result demand a more complex diagnostic technique based on tomographic phase reconstruction. We have used the 3D magnetoresistive hydrocode GORGON to model these systems and to highlight interesting features such as the formation of a Mach stem for further study.

  3. 29 CFR 1926.909 - Firing the blast.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Firing the blast. 1926.909 Section 1926.909 Labor...Explosives § 1926.909 Firing the blast. (a) A code of blasting signals...at suitable locations. (b) Before a blast is fired, a loud warning signal...

  4. 30 CFR 816.64 - Use of explosives: Blasting schedule.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...periods for blasting. (3) Unscheduled blasts may be conducted only where public or...When an operator conducts an unscheduled blast, the operator, using audible signals...document the reason for the unscheduled blast in accordance with § 816.68(p)....

  5. Membrane Transport Phenomena (MTP)

    NASA Technical Reports Server (NTRS)

    Mason, Larry W.

    1997-01-01

    The third semi-annual period of the MTP project has been involved with performing experiments using the Membrane Transport Apparatus (MTA), development of analysis techniques for the experiment results, analytical modeling of the osmotic transport phenomena, and completion of a DC-9 microgravity flight to test candidate fluid cell geometries. Preparations were also made for the MTP Science Concept Review (SCR), held on 13 June 1997 at Lockheed Martin Astronautics in Denver. These activities are detailed in the report.

  6. Electroosmotic Phenomena in Fractures

    Microsoft Academic Search

    S. Marino; D. Coelho; S. Békri; P. M. Adler

    2000-01-01

    Electroosmotic phenomena in fractures have been investigated in the linear limit for various double-layer thicknesses. The effects of the geometrical parameters were systematically studied for deterministic sinusoidal and random self-affine fractures. The numerical results show a definite influence of the surface amplitude on electroosmotic processes. For self-affine fractures, the roughness or Hurst exponent has a much larger incidence than the

  7. Chronic traumatic encephalopathy in blast-exposed military veterans and a blast neurotrauma mouse model.

    PubMed

    Goldstein, Lee E; Fisher, Andrew M; Tagge, Chad A; Zhang, Xiao-Lei; Velisek, Libor; Sullivan, John A; Upreti, Chirag; Kracht, Jonathan M; Ericsson, Maria; Wojnarowicz, Mark W; Goletiani, Cezar J; Maglakelidze, Giorgi M; Casey, Noel; Moncaster, Juliet A; Minaeva, Olga; Moir, Robert D; Nowinski, Christopher J; Stern, Robert A; Cantu, Robert C; Geiling, James; Blusztajn, Jan K; Wolozin, Benjamin L; Ikezu, Tsuneya; Stein, Thor D; Budson, Andrew E; Kowall, Neil W; Chargin, David; Sharon, Andre; Saman, Sudad; Hall, Garth F; Moss, William C; Cleveland, Robin O; Tanzi, Rudolph E; Stanton, Patric K; McKee, Ann C

    2012-05-16

    Blast exposure is associated with traumatic brain injury (TBI), neuropsychiatric symptoms, and long-term cognitive disability. We examined a case series of postmortem brains from U.S. military veterans exposed to blast and/or concussive injury. We found evidence of chronic traumatic encephalopathy (CTE), a tau protein-linked neurodegenerative disease, that was similar to the CTE neuropathology observed in young amateur American football players and a professional wrestler with histories of concussive injuries. We developed a blast neurotrauma mouse model that recapitulated CTE-linked neuropathology in wild-type C57BL/6 mice 2 weeks after exposure to a single blast. Blast-exposed mice demonstrated phosphorylated tauopathy, myelinated axonopathy, microvasculopathy, chronic neuroinflammation, and neurodegeneration in the absence of macroscopic tissue damage or hemorrhage. Blast exposure induced persistent hippocampal-dependent learning and memory deficits that persisted for at least 1 month and correlated with impaired axonal conduction and defective activity-dependent long-term potentiation of synaptic transmission. Intracerebral pressure recordings demonstrated that shock waves traversed the mouse brain with minimal change and without thoracic contributions. Kinematic analysis revealed blast-induced head oscillation at accelerations sufficient to cause brain injury. Head immobilization during blast exposure prevented blast-induced learning and memory deficits. The contribution of blast wind to injurious head acceleration may be a primary injury mechanism leading to blast-related TBI and CTE. These results identify common pathogenic determinants leading to CTE in blast-exposed military veterans and head-injured athletes and additionally provide mechanistic evidence linking blast exposure to persistent impairments in neurophysiological function, learning, and memory. PMID:22593173

  8. Chronic Traumatic Encephalopathy in Blast-Exposed Military Veterans and a Blast Neurotrauma Mouse Model

    PubMed Central

    Goldstein, Lee E.; Fisher, Andrew M.; Tagge, Chad A.; Zhang, Xiao-Lei; Velisek, Libor; Sullivan, John A.; Upreti, Chirag; Kracht, Jonathan M.; Ericsson, Maria; Wojnarowicz, Mark W.; Goletiani, Cezar J.; Maglakelidze, Giorgi M.; Casey, Noel; Moncaster, Juliet A.; Minaeva, Olga; Moir, Robert D.; Nowinski, Christopher J.; Stern, Robert A.; Cantu, Robert C.; Geiling, James; Blusztajn, Jan K.; Wolozin, Benjamin L.; Ikezu, Tsuneya; Stein, Thor D.; Budson, Andrew E.; Kowall, Neil W.; Chargin, David; Sharon, Andre; Saman, Sudad; Hall, Garth F.; Moss, William C.; Cleveland, Robin O.; Tanzi, Rudolph E.; Stanton, Patric K.; McKee, Ann C.

    2013-01-01

    Blast exposure is associated with traumatic brain injury (TBI), neuropsychiatric symptoms, and long-term cognitive disability. We examined a case series of postmortem brains from U.S. military veterans exposed to blast and/or concussive injury. We found evidence of chronic traumatic encephalopathy (CTE), a tau protein–linked neurodegenerative disease, that was similar to the CTE neuropathology observed in young amateur American football players and a professional wrestler with histories of concussive injuries. We developed a blast neurotrauma mouse model that recapitulated CTE-linked neuropathology in wild-type C57BL/6 mice 2 weeks after exposure to a single blast. Blast-exposed mice demonstrated phosphorylated tauopathy, myelinated axonopathy, microvasculopathy, chronic neuroinflammation, and neurodegeneration in the absence of macroscopic tissue damage or hemorrhage. Blast exposure induced persistent hippocampal-dependent learning and memory deficits that persisted for at least 1 month and correlated with impaired axonal conduction and defective activity-dependent long-term potentiation of synaptic transmission. Intracerebral pressure recordings demonstrated that shock waves traversed the mouse brain with minimal change and without thoracic contributions. Kinematic analysis revealed blast-induced head oscillation at accelerations sufficient to cause brain injury. Head immobilization during blast exposure prevented blast-induced learning and memory deficits. The contribution of blast wind to injurious head acceleration may be a primary injury mechanism leading to blast-related TBI and CTE. These results identify common pathogenic determinants leading to CTE in blast-exposed military veterans and head-injured athletes and additionally provide mechanistic evidence linking blast exposure to persistent impairments in neurophysiological function, learning, and memory. PMID:22593173

  9. Effects of Blast Overpressure on Neurons and Glial Cells in Rat Organotypic Hippocampal Slice Cultures

    PubMed Central

    Miller, Anna P.; Shah, Alok S.; Aperi, Brandy V.; Budde, Matthew D.; Pintar, Frank A.; Tarima, Sergey; Kurpad, Shekar N.; Stemper, Brian D.; Glavaski-Joksimovic, Aleksandra

    2015-01-01

    Due to recent involvement in military conflicts, and an increase in the use of explosives, there has been an escalation in the incidence of blast-induced traumatic brain injury (bTBI) among US military personnel. Having a better understanding of the cellular and molecular cascade of events in bTBI is prerequisite for the development of an effective therapy that currently is unavailable. The present study utilized organotypic hippocampal slice cultures (OHCs) exposed to blast overpressures of 150?kPa (low) and 280?kPa (high) as an in vitro bTBI model. Using this model, we further characterized the cellular effects of the blast injury. Blast-evoked cell death was visualized by a propidium iodide (PI) uptake assay as early as 2?h post-injury. Quantification of PI staining in the cornu Ammonis 1 and 3 (CA1 and CA3) and the dentate gyrus regions of the hippocampus at 2, 24, 48, and 72?h following blast exposure revealed significant time dependent effects. OHCs exposed to 150?kPa demonstrated a slow increase in cell death plateauing between 24 and 48?h, while OHCs from the high-blast group exhibited a rapid increase in cell death already at 2?h, peaking at ~24?h post-injury. Measurements of lactate dehydrogenase release into the culture medium also revealed a significant increase in cell lysis in both low- and high-blast groups compared to sham controls. OHCs were fixed at 72?h post-injury and immunostained for markers against neurons, astrocytes, and microglia. Labeling OHCs with PI, neuronal, and glial markers revealed that the blast-evoked extensive neuronal death and to a lesser extent loss of glial cells. Furthermore, our data demonstrated activation of astrocytes and microglial cells in low- and high-blasted OHCs, which reached a statistically significant difference in the high-blast group. These data confirmed that our in vitro bTBI model is a useful tool for studying cellular and molecular changes after blast exposure. PMID:25729377

  10. On the Propagation and Interaction of Spherical Blast Waves

    NASA Technical Reports Server (NTRS)

    Kandula, Max; Freeman, Robert

    2007-01-01

    The characteristics and the scaling laws of isolated spherical blast waves have been briefly reviewed. Both self-similar solutions and numerical solutions of isolated blast waves are discussed. Blast profiles in the near-field (strong shock region) and the far-field (weak shock region) are examined. Particular attention is directed at the blast overpressure and shock propagating speed. Consideration is also given to the interaction of spherical blast waves. Test data for the propagation and interaction of spherical blast waves emanating from explosives placed in the vicinity of a solid propellant stack are presented. These data are discussed with regard to the scaling laws concerning the decay of blast overpressure.

  11. Fluid dynamics of the 1997 Boxing Day volcanic blast on Montserrat, West Indies

    NASA Astrophysics Data System (ADS)

    Esposti Ongaro, T.; Clarke, A. B.; Neri, A.; Voight, B.; Widiwijayanti, C.

    2008-03-01

    Directed volcanic blasts are powerful explosions with a significant laterally directed component, which can generate devastating, high-energy pyroclastic density currents (PDCs). Such blasts are an important class of eruptive phenomena, but quantified understanding of their dynamics and effects is still incomplete. Here we use 2-D and 3-D multiparticle thermofluid dynamic flow codes to examine a powerful volcanic blast that occurred on Montserrat in December 1997. On the basis of the simulations, we divide the blast into three phases: an initial burst phase that lasts roughly 5 s and involves rapid expansion of the gas-pyroclast mixture, a gravitational collapse phase that occurs when the erupted material fails to mix with sufficient air to form a buoyant column and thus collapses asymmetrically, and a PDC phase that is dominated by motion parallel to the ground surface and is influenced by topography. We vary key input parameters such as total gas energy and total solid mass to understand their influence on simulations, and we compare the simulations with independent field observations of damage and deposits, demonstrating that the models generally capture important large-scale features of the natural phenomenon. We also examine the 2-D and 3-D model results to estimate the flow Mach number and conclude that the range of damage sustained at villages on Montserrat can be reasonably explained by the spatial and temporal distribution of the dynamic pressure associated with subsonic PDCs.

  12. LTC vacuum blasting machine (concrete): Baseline report

    SciTech Connect

    NONE

    1997-07-31

    The LTC shot blast technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The LTC 1073 Vacuum Blasting Machine uses a high-capacity, direct-pressure blasting system which incorporates a continuous feed for the blast media. The blast media cleans the surface within the contained brush area of the blast. It incorporates a vacuum system which removes dust and debris from the surface as it is blasted. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure during maintenance activities was minimal, but due to mechanical difficulties dust monitoring could not be conducted during operation. Noise exposure was significant. Further testing for each of these exposures is recommended because of the outdoor environment where the testing demonstration took place. This may cause the results to be inaccurate. It is feasible that the dust and noise levels will be higher in an enclosed environment. In addition, other safety and health issues found were ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, and arm-hand vibration.

  13. Effect of the Blasting Angle on Blast Processing of a Cylindrical Surface

    NASA Astrophysics Data System (ADS)

    Kubohori, Toshifumi; Binti Khalil, Nur Zalikha; Tojo, Yuichi; Takahashi, Shigetaka

    Blast processing is a substrate processing technique during which spherical or granular materials are jetted against the substrate surface using compressed air. Blasting techniques is widely used for various mechanical parts as a surface reforming technique. When performing blast processing to a complicated-shaped substrate for the purpose of thermal spraying method, it is difficult to set blasting angle to a constant value and it is necessary to clarify the effect of state of substrate on blast processing. In present paper, the effect of blasting angle to removal processing effect and the modification state of substrate is investigated. Results from this investigation are summarized as follows: When blasting angle ? was 30º, the removal quantity ? showed the maximum. The removal quantity became large as cylindrical diameter D was larger. Removal quantity of particle diameter a =100 ?m is bigger than that of a =700 ?m. As a nozzle movement rate v increased, removal quantity ? became small. As blasting angle ? became small, removal quantity ? became large even though nozzle movement rate v was changed. As blasting pressure P increases, removal quantity ? became big.

  14. MULTISCALE PHENOMENA IN MATERIALS

    SciTech Connect

    A. BISHOP

    2000-09-01

    This project developed and supported a technology base in nonequilibrium phenomena underpinning fundamental issues in condensed matter and materials science, and applied this technology to selected problems. In this way the increasingly sophisticated synthesis and characterization available for classes of complex electronic and structural materials provided a testbed for nonlinear science, while nonlinear and nonequilibrium techniques helped advance our understanding of the scientific principles underlying the control of material microstructure, their evolution, fundamental to macroscopic functionalities. The project focused on overlapping areas of emerging thrusts and programs in the Los Alamos materials community for which nonlinear and nonequilibrium approaches will have decisive roles and where productive teamwork among elements of modeling, simulations, synthesis, characterization and applications could be anticipated--particularly multiscale and nonequilibrium phenomena, and complex matter in and between fields of soft, hard and biomimetic materials. Principal topics were: (i) Complex organic and inorganic electronic materials, including hard, soft and biomimetic materials, self-assembly processes and photophysics; (ii) Microstructure and evolution in multiscale and hierarchical materials, including dynamic fracture and friction, dislocation and large-scale deformation, metastability, and inhomogeneity; and (iii) Equilibrium and nonequilibrium phases and phase transformations, emphasizing competing interactions, frustration, landscapes, glassy and stochastic dynamics, and energy focusing.

  15. Anomalous Light Phenomena vs. Bioelectric Brain Activity

    NASA Astrophysics Data System (ADS)

    Teodorani, M.; Nobili, G.

    We present a research proposal concerning the instrumented investigation of anomalous light phenomena that are apparently correlated with particular mind states, such as prayer, meditation or psi. Previous research by these authors demonstrate that such light phenomena can be monitored and measured quite efficiently in areas of the world where they are reported in a recurrent way. Instruments such as optical equipment for photography and spectroscopy, VLF spectrometers, magnetometers, radar and IR viewers were deployed and used massively in several areas of the world. Results allowed us to develop physical models concerning the structural and time-variable behaviour of light phenomena, and their kinematics. Recent insights and witnesses have suggested to us that a sort of "synchronous connection" seems to exist between plasma-like phenomena and particular mind states of experiencers who seem to trigger a light manifestation which is very similar to the one previously investigated. The main goal of these authors is now aimed at the search for a concrete "entanglement-like effect" between the experiencer's mind and the light phenomena, in such a way that both aspects are intended to be monitored and measured simultaneously using appropriate instrumentation. The goal of this research project is twofold: a) to verify quantitatively the existence of one very particular kind of mind-matter interaction and to study in real time its physical and biophysical manifestations; b) to repeat the same kind of experiment using the same test-subject in different locations and under various conditions of geomagnetic activity.

  16. A Parametric Approach to Shape Field-Relevant Blast Wave Profiles in Compressed-Gas-Driven Shock Tube

    PubMed Central

    Sundaramurthy, Aravind; Chandra, Namas

    2014-01-01

    Detonation of a high-explosive produces shock-blast wave, shrapnel, and gaseous products. While direct exposure to blast is a concern near the epicenter, shock-blast can affect subjects, even at farther distances. When a pure shock-blast wave encounters the subject, in the absence of shrapnels, fall, or gaseous products the loading is termed as primary blast loading and is the subject of this paper. The wave profile is characterized by blast overpressure, positive time duration, and impulse and called herein as shock-blast wave parameters (SWPs). These parameters in turn are uniquely determined by the strength of high explosive and the distance of the human subjects from the epicenter. The shape and magnitude of the profile determine the severity of injury to the subjects. As shown in some of our recent works (1–3), the profile not only determines the survival of the subjects (e.g., animals) but also the acute and chronic biomechanical injuries along with the following bio-chemical sequelae. It is extremely important to carefully design and operate the shock tube to produce field-relevant SWPs. Furthermore, it is vital to identify and eliminate the artifacts that are inadvertently introduced in the shock-blast profile that may affect the results. In this work, we examine the relationship between shock tube adjustable parameters (SAPs) and SWPs that can be used to control the blast profile; the results can be easily applied to many of the laboratory shock tubes. Further, replication of shock profile (magnitude and shape) can be related to field explosions and can be a standard in comparing results across different laboratories. Forty experiments are carried out by judiciously varying SAPs such as membrane thickness, breech length (66.68–1209.68?mm), measurement location, and type of driver gas (nitrogen, helium). The effects SAPs have on the resulting shock-blast profiles are shown. Also, the shock-blast profiles of a TNT explosion from ConWep software is compared with the profiles obtained from the shock tube. To conclude, our experimental results demonstrate that a compressed-gas shock tube when designed and operated carefully can replicate the blast time profiles of field explosions accurately. Such a faithful replication is an essential first step when studying the effects of blast induced neurotrauma using animal models. PMID:25520701

  17. Fluid/Structure Interaction Computational Investigation of Blast-Wave Mitigation Efficacy of the Advanced Combat Helmet

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Bell, W. C.; Pandurangan, B.; Glomski, P. S.

    2011-08-01

    To combat the problem of traumatic brain injury (TBI), a signature injury of the current military conflicts, there is an urgent need to design head protection systems with superior blast/ballistic impact mitigation capabilities. Toward that end, the blast impact mitigation performance of an advanced combat helmet (ACH) head protection system equipped with polyurea suspension pads and subjected to two different blast peak pressure loadings has been investigated computationally. A fairly detailed (Lagrangian) finite-element model of a helmet/skull/brain assembly is first constructed and placed into an Eulerian air domain through which a single planar blast wave propagates. A combined Eulerian/Lagrangian transient nonlinear dynamics computational fluid/solid interaction analysis is next conducted in order to assess the extent of reduction in intra-cranial shock-wave ingress (responsible for TBI). This was done by comparing temporal evolutions of intra-cranial normal and shear stresses for the cases of an unprotected head and the helmet-protected head and by correlating these quantities with the three most common types of mild traumatic brain injury (mTBI), i.e., axonal damage, contusion, and subdural hemorrhage. The results obtained show that the ACH provides some level of protection against all investigated types of mTBI and that the level of protection increases somewhat with an increase in blast peak pressure. In order to rationalize the aforementioned findings, a shockwave propagation/reflection analysis is carried out for the unprotected head and helmet-protected head cases. The analysis qualitatively corroborated the results pertaining to the blast-mitigation efficacy of an ACH, but also suggested that there are additional shockwave energy dissipation phenomena which play an important role in the mechanical response of the unprotected/protected head to blast impact.

  18. Perfluorocarbon vapor tagging of blasting cap detonators

    DOEpatents

    Dietz, Russell N. (Shoreham, NY); Senum, Gunnar I. (Patchogue, NY)

    1981-01-01

    A plug for a blasting cap is made of an elastomer in which is dissolved a perfluorocarbon. The perfluorocarbon is released as a vapor into the ambient over a long period of time to serve as a detectable taggant.

  19. Economical solutions to blast mitigation on bridges

    E-print Network

    DeRogatis, Austin (Austin Patrick)

    2008-01-01

    Mitigating the energy created from a blast has been a topic of utmost importance in the terrorism-feared world of today. Main targets of concern are passageways that are significant to a specific area, such as bridges. ...

  20. 30 CFR 58.610 - Abrasive blasting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...with the miner outside the device. (b) Underground areas of underground mines. Silica sand or other materials containing more than 1 percent free silica shall not be used as an abrasive substance in abrasive blasting. [59 FR 8327,...

  1. 30 CFR 72.610 - Abrasive blasting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...with the miner outside the device. (b) Underground areas of underground mines. Silica sand or other materials containing more than 1 percent free silica shall not be used as an abrasive substance in abrasive blasting. [59 FR 8327,...

  2. Localized coating removal using plastic media blasting

    NASA Technical Reports Server (NTRS)

    Novak, Howard L.; Wyckoff, Michael G.; Zook, Lee M.

    1988-01-01

    Steps taken to qualify the use of plastic media blasting for safely and effectively removing paint and other coatings from solid rocket booster aluminum structures are described. As a result of the effort, an improvement was made in the design of surface finishing equipment for processing flight hardware, in addition to a potentially patentable idea on improved plastic media composition. The general arrangement of the blast equipment and the nozzle configuration are presented.

  3. Critical distance for blast-resistant design

    NASA Astrophysics Data System (ADS)

    Dharaneepathy, M. V.; Rao, M. N. Keshava; Santhakumar, A. R.

    1995-02-01

    Blast loads have, in the recent past, become important service loads for certain categories of structures. An important task in blast-resistant design is to make a realistic prediction of the blast pressures. The distance of explosion from the structure is an important datum, governing the magnitude and duration of the blast loads. The current practice is to choose some arbitrary distance for design purposes. This paper presents some results of analytical studies to show that such a notion is likely to be erroneous, particularly for tall and slender structures. The elements of the blast phenomenon are reviewed, before going into the formulations leading to the 'critical blast distance' at which the transient dynamic response rises to a maximum. Based on the principle of Mach stem growth and consequent transformation of the spherical shock front into cylindrical or plane shock front, an expression for the distance at which the structure is fully engulfed by the Mach region is derived. This is the distance at which the cumulative blast effect reaches a maximum, and hence can be identified as critical distance. To verify this theory, certain numerical experiments are conducted on structures of different heights and diameters, such as cylindrical towers, a chimney and a cooling tower. The results of these studies have convincingly proved the existence of the critical ground-zero distance at which the cumulative blast effect reaches a maximum. It is concluded that this critical distance should be used as the design distance particularly for tall structures. It is also advisable to use a realistic type of shock front and shock reflection coefficient, consistent with the height of Mach stem, incidence angle and pressure magnitude.

  4. Space shuttle holddown post blast shield

    NASA Technical Reports Server (NTRS)

    Larracas, F. B.

    1991-01-01

    The original and subsequent designs of the Solid Rocket Booster/Holddown Post blast shield assemblies and their associated hardware are described. It presents the major problems encountered during their early use in the Space Shuttle Program, during the Return-to-Flight Modification Phase, and during their fabrication and validation testing phases. The actions taken to correct the problems are discussed, along with the various concepts now being considered to increase the useful life of the blast shield.

  5. Rice Blast Genomics: K12 Outreach

    NSDL National Science Digital Library

    This outreach component of the Rice Blast Project provides online genomics activities for high-school students. A lab manual is also offered free of charge to teachers of high-school biology in North Carolina, Texas, Kentucky, Arizona, Virginia, and Indiana. The Rice Blast Project is a collaboration of scientists from North Carolina State University, Texas A&M University, University of Kentucky, University of Arizona, Purdue University, Ohio State University, and Virginia Bioinformatics Institute.

  6. Lightweight Energy Absorbers for Blast Containers

    NASA Technical Reports Server (NTRS)

    Balles, Donald L.; Ingram, Thomas M.; Novak, Howard L.; Schricker, Albert F.

    2003-01-01

    Kinetic-energy-absorbing liners made of aluminum foam have been developed to replace solid lead liners in blast containers on the aft skirt of the solid rocket booster of the space shuttle. The blast containers are used to safely trap the debris from small explosions that are initiated at liftoff to sever frangible nuts on hold-down studs that secure the spacecraft to a mobile launch platform until liftoff.

  7. Computational Modeling and Optimization of a Novel Shock Tube to Study Blast Induced Traumatic Brain Injury

    E-print Network

    Anumolu, Pratima

    2014-08-06

    Over the last decade, soldiers fighting in Iraq and Afghanistan are being exposed to blasts from powerful explosives with improvised detonation techniques. These blasts put them at high risk of closed head non-impact Blast-induced Traumatic Blast...

  8. Blast-Induced Structural and Crack Response of a Brick Residential Structure Near an Aggregate Quarry

    E-print Network

    Instrumentation to Measure Structural Response Figure 1 shows a plan view of the instrumentation locations within: Plan View of Instrumented House (left) and Locations of Velocity Transducers to Measure StructuralBlast- Induced Structural and Crack Response of a Brick Residential Structure Near an Aggregate

  9. Ultra Safe And Secure Blasting System

    SciTech Connect

    Hart, M M

    2009-07-27

    The Ultra is a blasting system that is designed for special applications where the risk and consequences of unauthorized demolition or blasting are so great that the use of an extraordinarily safe and secure blasting system is justified. Such a blasting system would be connected and logically welded together through digital code-linking as part of the blasting system set-up and initialization process. The Ultra's security is so robust that it will defeat the people who designed and built the components in any attempt at unauthorized detonation. Anyone attempting to gain unauthorized control of the system by substituting components or tapping into communications lines will be thwarted in their inability to provide encrypted authentication. Authentication occurs through the use of codes that are generated by the system during initialization code-linking and the codes remain unknown to anyone, including the authorized operator. Once code-linked, a closed system has been created. The system requires all components connected as they were during initialization as well as a unique code entered by the operator for function and blasting.

  10. Methods for predicting rubble motion during blasting

    SciTech Connect

    Schamaun, J.T.

    1984-03-01

    Recent applications of explosives and blasting agents to rubble rock have led to requirements for more elaborate design and analysis methods. Many in situ extraction techniques require rubblization to take place in a confined region where rock motion is a predominate factor in creating a permeable broken bed. Two analytical methods are presented which describe the large rubble motion during blasting. These methods are intended to provide the blast designer with a tool for evaluation and further refinement of blasting patterns and timing sequences. In both these methods, the rock medium is represented by a series of discrete, discontinuous regions (bodies, masses). The use of discontinuous techniques rather than the classical continuum methods, results in better approximations to the rubble motion. These regions are set in motion by pressure loads from the explosive. The motion of these regions is then calculated numerically using interaction laws between regions in contact. The basis for these models or methods is presented along with the background for selecting explosive pressure loads and rock mass material behavior. Typical examples, including both cratering and bench blasting geometries, are discussed which illustrate the use of these models to predict rubble motion. Such engineering representations appear to provide a practical method for use in predicting rubble motion and a tool for design evaluation of blasting in confined geometries.

  11. Helmet liner evaluation to mitigate head response from primary blast exposure.

    PubMed

    Lockhart, Philip A; Cronin, Duane S

    2015-01-01

    Head injury resulting from blast loading, including mild traumatic brain injury, has been identified as an important blast-related injury in modern conflict zones. A study was undertaken to investigate potential protective ballistic helmet liner materials to mitigate primary blast injury using a detailed sagittal plane head finite element model, developed and validated against previous studies of head kinematics resulting from blast exposure. Five measures reflecting the potential for brain injury that were investigated included intracranial pressure, brain tissue strain, head acceleration (linear and rotational) and the head injury criterion. In simulations, these measures provided consistent predictions for typical blast loading scenarios. Considering mitigation, various characteristics of foam material response were investigated and a factor analysis was performed which showed that the four most significant were the interaction effects between modulus and hysteretic response, stress-strain response, damping factor and density. Candidate materials were then identified using the predicted optimal material values. Polymeric foam was found to meet the density and modulus requirements; however, for all significant parameters, higher strength foams, such as aluminum foam, were found to provide the highest reduction in the potential for injury when compared against the unprotected head. PMID:24559088

  12. Weld pool phenomena

    SciTech Connect

    David, S.A.; Vitek, J.M.; Zacharia, T. [Oak Ridge National Lab., TN (United States); DebRoy, T. [Pennsylvania State Univ., University Park, PA (United States)

    1994-09-01

    During welding, the composition, structure and properties of the welded structure are affected by the interaction of the heat source with the metal. The interaction affects the fluid flow, heat transfer and mass transfer in the weld pool, and the solidification behavior of the weld metal. In recent years, there has been a growing recognition of the importance of the weld pool transport processes and the solid state transformation reactions in determining the composition, structure and properties of the welded structure. The relation between the weld pool transport processes and the composition and structure is reviewed. Recent applications of various solidification theories to welding are examined to understand the special problems of weld metal solidification. The discussion is focussed on the important problems and issues related to weld pool transport phenomena and solidification. Resolution of these problems would be an important step towards a science based control of composition, structure and properties of the weld metal.

  13. Ground Deformation Analysis of Blast-Induced Liquefaction at a Simulated Airport Infrastructure Using High Resolution 3D Laser Scanning

    Microsoft Academic Search

    D. Minasian; R. Kayen; S. Ashford; Y. Kawamata; T. Sugano

    2008-01-01

    In October 2007, the Port and Airport Research Institute (PARI) of the Japan Ministry of Land, Infrastructure and Transportation conducted a large-scale blast-induced liquefaction experiment in Ishikari, Hokkaido, Japan. Approximately 24,000 m2 of ground was liquefied using controlled blasting techniques to investigate the performance of airport infrastructure. The USGS and Oregon State University participated in the study and measured topographic

  14. Gapped BLAST and PSI-BLAST: a new generation of protein database search programs

    Microsoft Academic Search

    Stephen F. Altschul; Thomas L. Madden; Alejandro A. Schäffer; Jinghui Zhang; Zheng Zhang; Webb C. Miller; David J. Lipman

    1997-01-01

    The BLAST programs are widely used tools for searching protein and DNA databases for sequence similarities. For protein comparisons, a variety of definitional, algorithmic and statistical refinements described here permits the execution time of the BLAST programs to be decreased substantially while enhancing their sensitivity to weak similarities. A new criterion for triggering the extension of word hits, combined with

  15. Effect of Blast-Induced Vibration from New Railway Tunnel on Existing Adjacent Railway Tunnel in Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Liang, Qingguo; Li, Jie; Li, Dewu; Ou, Erfeng

    2013-01-01

    The vibrations of existing service tunnels induced by blast-excavation of adjacent tunnels have attracted much attention from both academics and engineers during recent decades in China. The blasting vibration velocity (BVV) is the most widely used controlling index for in situ monitoring and safety assessment of existing lining structures. Although numerous in situ tests and simulations had been carried out to investigate blast-induced vibrations of existing tunnels due to excavation of new tunnels (mostly by bench excavation method), research on the overall dynamical response of existing service tunnels in terms of not only BVV but also stress/strain seemed limited for new tunnels excavated by the full-section blasting method. In this paper, the impacts of blast-induced vibrations from a new tunnel on an existing railway tunnel in Xinjiang, China were comprehensively investigated by using laboratory tests, in situ monitoring and numerical simulations. The measured data from laboratory tests and in situ monitoring were used to determine the parameters needed for numerical simulations, and were compared with the calculated results. Based on the results from in situ monitoring and numerical simulations, which were consistent with each other, the original blasting design and corresponding parameters were adjusted to reduce the maximum BVV, which proved to be effective and safe. The effect of both the static stress before blasting vibrations and the dynamic stress induced by blasting on the total stresses in the existing tunnel lining is also discussed. The methods and related results presented could be applied in projects with similar ground and distance between old and new tunnels if the new tunnel is to be excavated by the full-section blasting method.

  16. Hydrocortisone in culture protects the blast cells in acute myeloblastic leukemia from the lethal effects of cytosine arabinoside

    SciTech Connect

    Yang, G.S.; Wang, C.; Minkin, S.; Minden, M.D.; McCulloch, E.A. (Ontario Cancer Institute, University of Toronto (Canada))

    1991-07-01

    The blast cells in acute myeloblastic leukemia (AML) respond to many of the same regulatory mechanisms that control normal hemopoiesis. These include the growth factors that bind to membrane receptors and steroid hormones or vitamins that have intracellular receptors. The authors report the effects in culture of the steroid glucocorticoid hydrocortisone on freshly explanted AML blasts from patients and on two continuous AML cell lines. Only small changes in clonogenic cell numbers in suspension cultures were seen in the presence of hydrocortisone. The most striking effect of the hormone was on the sensitivity of blasts cells to cytosine arabinoside (ara-C). In contrast to the response of AML blast cells to retinoic acid, a ligand for intracellular steroid receptors that sensitizes some blast populations to ara-C, hydrocortisone reduced the toxic effects of the drug. The protective action of hydrocortisone was not mediated through the cell cycle since exposure of blasts to hydrocortisone did not affect the percentage of cells in DNA synthesis as measured with the tritiated thymidine (3HTdR) suicide technique. The hydrocortisone effect could be demonstrated using a pulse (20 min) exposure protocol. Blasts pulsed with increasing specific activities of 3HTdR showed the usual response pattern with an initial loss in plating efficiency to about 50% of control, followed by a plateau, regardless of whether the cells had been exposed to hydrocortisone. Control blasts exposed to increasing ara-C concentrations gave very similar dose-response curves; in striking contrast, blast cells cultured in hydrocortisone, then pulsed with ara-C did not lose colony-forming ability even though the same population was sensitive to 3HTdR.

  17. Smooth blasting with the electronic delay detonator

    SciTech Connect

    Yamamoto, Masaaki [Asahi Chemical Industry Co., Ltd. (Japan); Ichijo, Toshiyuki; Tanaka, Yoshiharu

    1995-12-31

    The authors utilized electronic detonators (EDs) to investigate the effect of high detonator delay accuracy on overbreak, remaining rock damage, and surface smoothness, in comparison with that of long-period delay detonators (0.25 sec interval) PDs. The experiments were conducted in a deep mine, in a test site region composed of very hard granodiorite with a seismic wave velocity of about 6.0 km/sec and a uniaxial compressive strength, uniaxial tensile strength, and Young`s modulus of 300 MPa, 12 MPa, and 73 GPa, respectively. The blasting design was for a test tunnel excavation of 8 m{sup 2} in cross section, with an advance per round of 2.5 m. Five rounds were performed, each with a large-hole cut and perimeter holes in a 0.4-m spacing charged with 20-mm-diameter water gel explosive to obtain low charge concentration. EDs were used in the holes on the perimeter of the right half, and PDs were used in all other holes. Following each shot, the cross section was measured by laser to determine amount of overbreak and surface smoothness. In situ seismic prospecting was used to estimate the depth of damage in the remaining rock, and the damage was further investigated by boring into both side walls.

  18. Characterization of blasted austenitic stainless steel and its corrosion resistance

    NASA Astrophysics Data System (ADS)

    Otsubo, F.; Kishitake, K.; Akiyama, T.; Terasaki, T.

    2003-12-01

    It is known that the corrosion resistance of stainless steel is deteriorated by blasting, but the reason for this deterioration is not clear. A blasted austenitic stainless steel plate (JIS-SUS304) has been characterized with comparison to the scraped and non-blasted specimens. The surface roughness of the blasted specimen is larger than that of materials finished with #180 paper. A martensite phase is formed in the surface layer of both blasted and scraped specimens. Compressive residual stress is generated in the blasted specimen and the maximum residual stress is formed at 50 100 µm from the surface. The corrosion potentials of the blasted specimen and subsequently solution treated specimen are lower than that of the non-blasted specimen. The passivation current densities of the blasted specimens are higher those of the non-blasted specimen. The blasted specimen and the subsequently solution treated specimen exhibit rust in 5% sodium chloride (NaCl) solution, while the non-blasted specimen and ground specimen do not rust in the solution. It is concluded that the deterioration of corrosion resistance of austenitic stainless steel through blasting is caused by the roughed morphology of the surface.

  19. Lidar and radar measurements of the melting layer in the frame of the Convective and Orographically-induced Precipitation Study: observations of dark and bright band phenomena

    NASA Astrophysics Data System (ADS)

    di Girolamo, P.; Summa, D.; Bhawar, R.; di Iorio, T.; Norton, E. G.; Peters, G.; Dufournet, Y.

    2011-11-01

    During the Convective and Orographically-induced Precipitation Study (COPS), lidar dark and bright bands were observed by the University of BASILicata Raman lidar system (BASIL) during several intensive (IOPs) and special (SOPs) observation periods (among others, 23 July, 15 August, and 17 August 2007). Lidar data were supported by measurements from the University of Hamburg cloud radar MIRA 36 (36 GHz), the University of Hamburg dual-polarization micro rain radars (24.1 GHz) and the University of Manchester UHF wind profiler (1.29 GHz). Results from BASIL and the radars for 23 July 2007 are illustrated and discussed to support the comprehension of the microphysical and scattering processes responsible for the appearance of the lidar and radar dark and bright bands. Simulations of the lidar dark and bright band based on the application of concentric/eccentric sphere Lorentz-Mie codes and a melting layer model are also provided. Lidar and radar measurements and model results are also compared with measurements from a disdrometer on ground and a two-dimensional cloud (2DC) probe on-board the ATR42 SAFIRE.

  20. Alkahest NuclearBLAST : a user-friendly BLAST management and analysis system

    PubMed Central

    Diener, Stephen E; Houfek, Thomas D; Kalat, Sam E; Windham, DE; Burke, Mark; Opperman, Charles; Dean, Ralph A

    2005-01-01

    Background - Sequencing of EST and BAC end datasets is no longer limited to large research groups. Drops in per-base pricing have made high throughput sequencing accessible to individual investigators. However, there are few options available which provide a free and user-friendly solution to the BLAST result storage and data mining needs of biologists. Results - Here we describe NuclearBLAST, a batch BLAST analysis, storage and management system designed for the biologist. It is a wrapper for NCBI BLAST which provides a user-friendly web interface which includes a request wizard and the ability to view and mine the results. All BLAST results are stored in a MySQL database which allows for more advanced data-mining through supplied command-line utilities or direct database access. NuclearBLAST can be installed on a single machine or clustered amongst a number of machines to improve analysis throughput. NuclearBLAST provides a platform which eases data-mining of multiple BLAST results. With the supplied scripts, the program can export data into a spreadsheet-friendly format, automatically assign Gene Ontology terms to sequences and provide bi-directional best hits between two datasets. Users with SQL experience can use the database to ask even more complex questions and extract any subset of data they require. Conclusion - This tool provides a user-friendly interface for requesting, viewing and mining of BLAST results which makes the management and data-mining of large sets of BLAST analyses tractable to biologists. PMID:15958161

  1. The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) 2005: Calibration and Targeted Sources

    E-print Network

    M. D. P. Truch; P. A. R. Ade; J. J. Bock; E. L. Chapin; M. J. Devlin; S. Dicker; M. Griffin; J. O. Gundersen; M. Halpern; P. C. Hargrave; D. H. Hughes; J. Klein; G. Marsden; P. G. Martin; P. Mauskopf; C. B. Netterfield; L. Olmi; E. Pascale; G. Patanchon; M. Rex; D. Scott; C. Semisch; C. Tucker; G. S. Tucker; M. P. Viero; D. V. Wiebe

    2008-03-31

    The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) operated successfully during a 100-hour flight from northern Sweden in June 2005 (BLAST05). As part of the calibration and pointing procedures, several compact sources were mapped, including solar system, Galactic, and extragalactic targets, specifically Pallas, CRL 2688, LDN 1014, IRAS 20126+4104, IRAS 21078+5211, IRAS 21307+5049, IRAS 22134+5834, IRAS 23011+6126, K3-50, W 75N, and Mrk 231. One additional source, Arp 220, was observed and used as our primary calibrator. Details of the overall BLAST05 calibration procedure are discussed here. The BLAST observations of each compact source are described, flux densities and spectral energy distributions are reported, and these are compared with previous measurements at other wavelengths. The 250, 350, and 500 um BLAST data can provide useful constraints to the amplitude and slope of the submillimeter continuum, which in turn may be useful for the improved calibration of other submillimeter instruments.

  2. Arcjet cathode phenomena

    NASA Technical Reports Server (NTRS)

    Curran, Francis M.; Haag, Thomas W.; Raquet, John F.

    1989-01-01

    Cathode tips made from a number of different materials were tested in a modular arcjet thruster in order to examine cathode phenomena. Periodic disassembly and examination, along with the data collected during testing, indicated that all of the tungsten-based materials behaved similarly despite the fact that in one of these samples the percentage of thorium oxide was doubled and another was 25 percent rhenium. The mass loss rate from a 2 percent thoriated rhenium cathode was found to be an order of magnitude greater than that observed using 2 percent thoriated tungsten. Detailed analysis of one of these cathode tips showed that the molten crater contained pure tungsten to a depth of about 150 microns. Problems with thermal stress cracking were encountered in the testing of a hafnium carbide tip. Post test analysis showed that the active area of the tip had chemically reacted with the propellant. A 100 hour continuous test was run at about 1 kW. Post test analysis revealed no dendrite formation, such as observed in a 30 kW arcjet lifetest, near the cathode crater. The cathodes from both this test and a previously run 1000 hour cycled test displayed nearly identical arc craters. Data and calculations indicate that the mass losses observed in testing can be explained by evaporation.

  3. Arcjet Cathode Phenomena

    NASA Technical Reports Server (NTRS)

    Curran, Francis M.; Haag, Thomas W.; Raquet, John F.

    1989-01-01

    Cathode tips made from a number of different materials were tested in a modular arcjet thruster in order to examine cathode phenomena. Periodic disassembly and examination, along with the data collected during testing, indicated that all of the tungsten-based materials behaved similarly despite the fact that in one of these samples the percentage of thorium oxide was doubled and another was 25 percent rhenium. The mass loss rate from a 2 percent thoriated rhenium cathode was found to be an order of magnitude greater than that observed using 2 percent thoriated tungsten. Detailed analysis of one of these cathode tips showed that the molten crater contained pure tungsten to a depth of about 150 microns. Problems with thermal stress cracking were encountered in the testing of a hafnium carbide tip. Post test analysis showed that the active area of the tip had chemically reacted with the propellant. A 100 hour continuous test was run at about 1 kW. Post test analysis revealed no dendrite formation, such as observed in a 30 kW arcjet lifetest, near the cathode crater. The cathodes from both this test and a previously run 1000 hour cycled test displayed nearly identical arc craters. Data and calculations indicate that the mass losses observed in testing can be explained by evaporation.

  4. ON DETECTING TRANSIENT PHENOMENA

    SciTech Connect

    Belanger, G., E-mail: gbelanger@sciops.esa.int [European Space Astronomy Centre (ESA/ESAC), Science Operations Department, Villanueva de la Canada (Madrid) (Spain)

    2013-08-10

    Transient phenomena are interesting and potentially highly revealing of details about the processes under observation and study that could otherwise go unnoticed. It is therefore important to maximize the sensitivity of the method used to identify such events. In this article, we present a general procedure based on the use of the likelihood function for identifying transients which is particularly suited for real-time applications because it requires no grouping or pre-processing of the data. The method makes use of all the information that is available in the data throughout the statistical decision-making process, and is suitable for a wide range of applications. Here we consider those most common in astrophysics, which involve searching for transient sources, events or features in images, time series, energy spectra, and power spectra, and demonstrate the use of the method in the case of a weak X-ray flare in a time series and a short-lived quasi-periodic oscillation in a power spectrum. We derive a fit statistic that is ideal for fitting arbitrarily shaped models to a power density distribution, which is of general interest in all applications involving periodogram analysis.

  5. VIEW FACING EAST, VIEW FROM RIVER OF BLAST FURNACE NO. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FACING EAST, VIEW FROM RIVER OF BLAST FURNACE NO. 3. DORR THICKENER & ORE BRIDGE AT LEFT, HOT BLAST STOVES & DUST CATCHER CENTER, CAST HOUSE AT RIGHT. - Pittsburgh Steel Company, Monessen Works, Donner Avenue, Monessen, Westmoreland County, PA

  6. Use of probabilistic methods in evaluating blast performance of structures

    E-print Network

    Gillis, Andrew Nicholas

    2011-01-01

    The social and political climate of the modern world has lead to increased concern over the ability of engineered structures to resist blast events which may be incurred during terrorist attacks. While blast resistance ...

  7. 30 CFR 75.1310 - Explosives and blasting equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...blasting units shall be taken or used underground. (b) Black blasting powder, aluminum-cased detonators, aluminum-alloy-cased detonators, detonators with aluminum leg wires, and safety fuses shall not be taken or used...

  8. 30 CFR 57.20031 - Blasting underground in hazardous areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...false Blasting underground in hazardous areas. 57.20031 Section 57.20031 ...20031 Blasting underground in hazardous areas. In underground areas where dangerous accumulations of water, gas, mud, or fire atmosphere could be...

  9. DETAIL VIEW OF BLAST FURNACE NO. 3 AREA BELOW BUSTLE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF BLAST FURNACE NO. 3 AREA BELOW BUSTLE PIPE, CINDER NOTCH IN CENTER, SLAG RUNNER IN FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

  10. INTERIOR VIEW OF BLAST FURNACE NO. 3 LOOKING EAST, SLAG ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF BLAST FURNACE NO. 3 LOOKING EAST, SLAG RUNNERS & GATES IN FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

  11. 30 CFR 57.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Extraneous Electricity-Surface and Underground § 57.6605 Isolation of blasting...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  12. 30 CFR 56.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Extraneous Electricity § 56.6605 Isolation of blasting circuits. Lead...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  13. 30 CFR 56.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Extraneous Electricity § 56.6605 Isolation of blasting circuits. Lead...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  14. 30 CFR 56.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Extraneous Electricity § 56.6605 Isolation of blasting circuits. Lead...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  15. 30 CFR 57.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Extraneous Electricity-Surface and Underground § 57.6605 Isolation of blasting...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  16. 30 CFR 57.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Extraneous Electricity-Surface and Underground § 57.6605 Isolation of blasting...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  17. 30 CFR 57.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Extraneous Electricity-Surface and Underground § 57.6605 Isolation of blasting...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  18. 30 CFR 57.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Extraneous Electricity-Surface and Underground § 57.6605 Isolation of blasting...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  19. 30 CFR 56.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Extraneous Electricity § 56.6605 Isolation of blasting circuits. Lead...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  20. 30 CFR 56.6605 - Isolation of blasting circuits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Extraneous Electricity § 56.6605 Isolation of blasting circuits. Lead...tracks, and shall be protected from sources of stray or static electricity. Blasting circuits shall be protected from any...

  1. The Role of Family Phenomena in Posttraumatic Stress in Youth

    PubMed Central

    Deatrick, Janet A.

    2010-01-01

    Topic Youth face trauma that can cause posttraumatic stress (PTS). Purpose 1). To identify the family phenomena used in youth PTS research; and 2). Critically examine the research findings regarding the relationship between family phenomena and youth PTS. Sources Systematic literature review in PsycInfo, PILOTS, CINAHL, and MEDLINE. Twenty-six empirical articles met inclusion criteria. Conclusion Measurement of family phenomena included family functioning, support, environment, expressiveness, relationships, cohesion, communication, satisfaction, life events related to family, parental style of influence, and parental bonding. Few studies gave clear conceptualization of family or family phenomena. Empirical findings from the 26 studies indicate inconsistent empirical relationships between family phenomena and youth PTS, though a majority of the prospective studies support a relationship between family phenomena and youth PTS. Future directions for leadership by psychiatric nurses in this area of research and practice are recommended. PMID:21344778

  2. Modelling human eye under blast loading.

    PubMed

    Esposito, L; Clemente, C; Bonora, N; Rossi, T

    2015-01-01

    Primary blast injury (PBI) is the general term that refers to injuries resulting from the mere interaction of a blast wave with the body. Although few instances of primary ocular blast injury, without a concomitant secondary blast injury from debris, are documented, some experimental studies demonstrate its occurrence. In order to investigate PBI to the eye, a finite element model of the human eye using simple constitutive models was developed. The material parameters were calibrated by a multi-objective optimisation performed on available eye impact test data. The behaviour of the human eye and the dynamics of mechanisms occurring under PBI loading conditions were modelled. For the generation of the blast waves, different combinations of explosive (trinitrotoluene) mass charge and distance from the eye were analysed. An interpretation of the resulting pressure, based on the propagation and reflection of the waves inside the eye bulb and orbit, is proposed. The peculiar geometry of the bony orbit (similar to a frustum cone) can induce a resonance cavity effect and generate a pressure standing wave potentially hurtful for eye tissues. PMID:23521031

  3. Theoretical Concept to Understand Plan and Design Smooth Blasting Pattern

    Microsoft Academic Search

    S. K. Mandal; M. M. Singh; S. Dasgupta

    2008-01-01

    Considering different mechanical cutting tools for excavation of rock, drilling and blasting is said to be inexpensive and\\u000a at the same time most acceptable and compatible to any geo-excavation condition. Depending upon strength properties of in-situ\\u000a rock mass, characteristics of joint pattern and required quality of blasting, control blasting techniques viz., pre-split\\u000a and smooth blasting are commonly implemented to achieve

  4. A Dimensional Analysis Approach to Study Blast-Induced Ground Vibration

    NASA Astrophysics Data System (ADS)

    Khandelwal, Manoj; Saadat, Mahdi

    2015-03-01

    The prediction of ground vibration is of great importance in the alleviation of the detrimental effects of blasting. Therefore, a vibration control study to minimize the harm of ground vibration and its influence on nearby structures can play an important role in the mining industry. In this paper, a dimensional analysis (DA) technique has been performed on various blast design parameters to propose a new formula for the prediction of the peak particle velocity (PPV). After obtaining the DA formula, 105 data sets were used to determine the unknown coefficients of the DA equation, as well as site constants of different conventional predictor equations. Then, 12 new blast data sets were used to compare the capability of the DA formula with conventional predictor equations. The results were compared based on the coefficient of determination and mean absolute error between measured and predicted values of the PPV.

  5. Air blast reflecting on a rigid cylinder: simulation and reduced scale experiments

    NASA Astrophysics Data System (ADS)

    Langlet, A.; Souli, M.; Aquelet, N.; Pennetier, O.; Girault, G.

    2015-01-01

    In this paper, the Multi-Material ALE formulation is applied to simulate the propagation of an air blast through the atmosphere, and its reflection on an assumed rigid cylindrical obstacle. The mathematical and numerical implementations of this formulation are presented. In order to validate the formulation and prove its ability to capture the propagation and reflection of high pressure waves, comparisons of the simulations with the experimental blast pressure measured on an assumed rigid cylinder are performed. The simulation conducted via the presented models and methods gives good predictions for pressure time histories recorded on the rigid cylinder.

  6. Chemical changes of lakes within the Mount St. Helens blast zone

    SciTech Connect

    Wissmar, R.C.; Devol, A.H.; Nevissi, A.E.; Sedell, J.R.

    1982-01-01

    Differences in the dissolved chemistry of lakes devastated by the 18 May 1980 eruption of Mount St. Helens are attributable to location relative to the lateral blast trajectory of the eruption and to the emplacement of mineral deposits. Elemental enrichment ratios of pre- and posteruption measurements for Spirit Lake and comparisons of the chemical concentrations and elemental ratios for lakes inside and outside the blast zone reflect the influences of the dissolution of magmatic and lithic deposits. The pH changes were minor because of buffering by carbonic acid and reactions involving mineral alteration, dissolved organics, and biological processes.

  7. Hypervelocity impact phenomena

    SciTech Connect

    Chhabildas, L.C.

    1995-07-01

    There is a need to determine the equations of state of materials in regimes of extreme high pressures, temperatures and strain rates that are not attainable on current two-stage light-gas guns. Understanding high-pressure material behavior is crucial to address the physical processes associated with a variety of hypervelocity impact events related to space sciences-orbital-debris impact, debris-shield designs, high-speed plasma propagation, and impact lethality applications. At very high impact velocities material properties will be dominated by phase-changes, such as melting or vaporization, which cannot be achieved at lower impact velocities. Development of well-controlled and repeatable hypervelocity launch capabilities is the first step necessary to improve our understanding of material behavior at extreme pressures and temperatures not currently available using conventional two-stage light-gas gun techniques. In this paper, techniques that have been used to extend both the launch capabilities of a two-stage light gas gun to 16 km/s, and their use to determine the material properties at pressures and temperature states higher than those ever obtained in the laboratory are summarized. The newly developed hypervelocity launcher (HVL) can launch intact (macroscopic dimensions) plates to 16 km/s. Time-resolved interferometric techniques have been used to determine shock-loading/release characteristics of materials impacted by such fliers as well as shock-induced vaporization phenomena in fully vaporized states. High-speed photography or radiography has been used to evaluate the debris propagation characteristics resulting from disc impact of thin bumper sheets at hypervelocities in excess of 10 km/s using the HVL. Examples of these experiments are provided in this paper.

  8. Teaching Optical Phenomena with Tracker

    ERIC Educational Resources Information Center

    Rodrigues, M.; Carvalho, P. Simeão

    2014-01-01

    Since the invention and dissemination of domestic laser pointers, observing optical phenomena is a relatively easy task. Any student can buy a laser and experience at home, in a qualitative way, the reflection, refraction and even diffraction phenomena of light. However, quantitative experiments need instruments of high precision that have a…

  9. An efficient square-root algorithm for BLAST

    Microsoft Academic Search

    Babak Hassibi

    2000-01-01

    Bell Labs Layered Space-Time (BLAST) is a scheme for transmitting information over a rich-scattering wireless environment using multiple receive and transmit antennas. The main computational bottleneck in the BLAST algorithm is a “nulling and cancellation” step, where the optimal ordering for the sequential estimation and detection of the received signals is determined. To reduce the computational cost of BLAST, we

  10. 30 CFR 75.1320 - Multiple-shot blasting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false Multiple-shot blasting. 75.1320...and Blasting § 75.1320 Multiple-shot blasting. (a...round shall be initiated in sequence from the opener hole or holes...round shall be initiated in sequence from the opener hole or...

  11. BLAST FURNACE CAST HOUSE EMISSION CONTROL TECHNOLOGY ASSESSMENT

    EPA Science Inventory

    The study describes the state-of-the-art of controlling fumes escaping from blast furnace cast houses. Background information is based on: a study of existing literature; visits to blast furnaces in the U.S., Japan, and Europe; meetings with an ad hoc group of experienced blast f...

  12. Test of Some Hybrid Combinations to Rice Blast

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease caused by Magnaporthe oryzae is one of the most devastating rice diseases worldwide. Blast resistant cultivars are recognized as the most efficacious and economical way to control this disease. Genetic resistance to rice blast is generally governed by a few major genes, often in c...

  13. Cell adhesion and related phenomena on the surface-modified Au-deposited nerve microelectrode examined by total impedance measurement and cell detachment tests

    NASA Astrophysics Data System (ADS)

    Chang, Cheng-Hung; Liao, Jiunn-Der; Chen, Jia-Jin Jason; Ju, Ming-Shaung; Lin, Chou-Ching K.

    2006-05-01

    This study investigated alkanethiolate self-assembled monolayers (SAMs) of varied chain lengths adsorbed upon novel Au-coated microelectrodes, of which the surface properties were quantitatively evaluated by surface characterization and 3T3 fibroblast cell adhesion, total impedance and cell detachment tests. Thin-film SAMs adsorbed upon Au/PI/Si provided a hydrophobic or passive surface with increased water contact angle and initial total impedance. From cell adhesion tests, we can observe that the film formed as a dense-packed spacer resulted in incomplete cell sealing of 3T3 cells upon the surface-modified microelectrode. Thus the decrease in cell coverage rate and in the slope in association with total impedance as a function of cell-surface reaction time can be found. To study the adhesion force of a comparable single cell attached upon varied modified surfaces, a cell detachment test using a triangular probe tip of a well defined cantilever was carried out in medium containing fibroblast cells. Overall, both the peak force and the work required to detach a comparable single cell from the anchoring domain corresponded well to the increased length of alkyl chains adsorbed upon Au/PI/Si. Both measurements on the SAM modified surfaces demonstrated much smaller values than those on the pristine Au/PI/Si surface. These results concluded that a cell-repulsive characteristic was clearly formed on the SAM modified microelectrode surface. The non-adhering properties of surface-modified microelectrodes should provide better sensitivity for neuromuscular stimulation as well as for the recording of infinitesimal neural signals in future applications of neural prostheses.

  14. Critical phenomena in complex networks

    E-print Network

    Dorogovtsev, S N; Mendes, J F F

    2007-01-01

    The combination of the compactness of networks and their complex architectures results in a variety of critical effects dramatically different from those in cooperative systems on lattices. In the last few years, researchers have made important steps toward understanding the qualitatively new critical phenomena in complex networks. We review the results, concepts, and methods of this rapidly developing field. Here we mostly consider two closely related classes of these critical phenomena, namely structural phase transitions in the network architectures and transitions in cooperative models on networks as substrates. We also discuss systems where a network and interacting agents on it influence each other. We overview a wide range of critical phenomena in equilibrium and growing networks including the birth of the giant connected component, percolation, k-core percolation, phenomena near epidemic thresholds, condensation transitions, critical phenomena in spin models placed on networks, synchronisation, and se...

  15. Computation of blast wave-obstacle interactions

    NASA Technical Reports Server (NTRS)

    Champney, J. M.; Chaussee, D. S.; Kutler, P.

    1982-01-01

    Numerical simulations of the interaction of a planar blast wave with various obstacles are presented. These obstacles are either ground structures or vehicles flying in the atmosphere. For a structure on the ground, the blast wave encounter is side-on, while for the flying vehicles the encounter is either head-on or oblique. Second-order accurate, finite-difference, and shock-capturing procedures are employed to solve the two-dimensional, axisymmetric, and three-dimensional unsteady Euler equations. Results are presented for the flow field consisting of blast wave striking obstacles that are at rest, moving subsonically and moving supersonically. Comparison of the numerical results with experimental data for a configuration at rest substantiates the validity of this approach and its potential as a flow analysis tool.

  16. Surface treatment of wire electro-discharge machined engineering ceramics by abrasive blasting

    Microsoft Academic Search

    T. C. Lee; J. H. Zhang

    1998-01-01

    The surface integrity of electro-discharge machined engineering ceramics and their surface modification by abrasive blasting have been investigated in this study. Flexural strength was used for evaluating the effect of the two machining processes on the surface of machined specimens. The distributions of strength data were further analyzed by the Weibull statistical method to give a quantitative measure of the

  17. Planar blast scaling with condensed-phase explosives in a shock tube

    SciTech Connect

    Jackson, Scott L [Los Alamos National Laboratory

    2011-01-25

    Blast waves are strong shock waves that result from large power density deposition into a fluid. The rapid energy release of high-explosive (HE) detonation provides sufficiently high power density for blast wave generation. Often it is desirable to quantify the energy released by such an event and to determine that energy relative to other reference explosives to derive an explosive-equivalence value. In this study, we use condensed-phase explosives to drive a blast wave in a shock tube. The explosive material and quantity were varied to produce blast waves of differing strengths. Pressure transducers at varying lengths measured the post-shock pressure, shock-wave arrival time and sidewall impulse associated with each test. Blast-scaling concepts in a one-dimensional geometry were then used to both determine the energy release associated with each test and to verify the scaling of the shock position versus time, overpressure versus distance, and impulse. Most blast scaling measurements to-date have been performed in a three-dimensional geometry such as a blast arena. Testing in a three-dimensional geometry can be challenging, however, as spherical shock-wave symmetry is required for good measurements. Additionally, the spherical wave strength decays rapidly with distance and it can be necessary to utilize larger (several kg) quantities of explosive to prevent significant decay from occurring before an idealized blast wave has formed. Such a mode of testing can be expensive, require large quantities of explosive, and be limited by both atmospheric conditions (such as rain) and by noise complaints from the population density near the test arena. Testing is possible in more compact geometries, however. Non-planar blast waves can be formed into a quasi-planar shape by confining the shock diffraction with the walls of a shock tube. Regardless of the initial form, the wave shape will begin to approximate a planar front after successive wave reflections from the tube walls. Such a technique has previously been used to obtain blast scaling measurements in the planar geometry with gaseous explosives and the condensed-phase explosive nitroguanidine. Recently, there has been much interest in the blast characterization of various non-ideal high explosive (NIHE) materials. With non-ideals, the detonation reaction zone is significantly larger (up to several cm for ANFO) than more ideal explosives. Wave curvature, induced by charge-geometry, can significantly affect the energy release associated with NIHEs. To measure maximum NIHE energy release accurately, it is desirable to minimize any such curvature and, if possible, to overdrive the detonation shock to ensure completion of chemical reactions ahead of the sonic locus associated with the reaction zone. This is achieved in the current study through use of a powerful booster HE and a charge geometry consisting of short cylindrical lengths of NIHE initiated along the charge centerline.

  18. Visualization of explosion phenomena using a high-speed video camera with an uncoupled objective lens by fiber-optic

    NASA Astrophysics Data System (ADS)

    Tokuoka, Nobuyuki; Miyoshi, Hitoshi; Kusano, Hideaki; Hata, Hidehiro; Hiroe, Tetsuyuki; Fujiwara, Kazuhito; Yasushi, Kondo

    2008-11-01

    Visualization of explosion phenomena is very important and essential to evaluate the performance of explosive effects. The phenomena, however, generate blast waves and fragments from cases. We must protect our visualizing equipment from any form of impact. In the tests described here, the front lens was separated from the camera head by means of a fiber-optic cable in order to be able to use the camera, a Shimadzu Hypervision HPV-1, for tests in severe blast environment, including the filming of explosions. It was possible to obtain clear images of the explosion that were not inferior to the images taken by the camera with the lens directly coupled to the camera head. It could be confirmed that this system is very useful for the visualization of dangerous events, e.g., at an explosion site, and for visualizations at angles that would be unachievable under normal circumstances.

  19. Increase in the productivity of blast-furnace stoves

    SciTech Connect

    Solomentsev, S.L.; Chernobrivets, B.F.; Sigmund, V.K.; Basukinskii, S.M.; Beremblyum, G.B.; Nakhaev, P.E.; Serpevskii, S.L.

    1988-03-01

    The Novolipetsk combine proposed sending a cold blast through a special 150-mm-diameter pipe passing through an igniter opening into the combustion chamber. To evaluate the efficiency the stove performance in which some of the cold blast was directed to the combustion chamber was compared against that of unmodified stoves. This blast-delivery system was found to increase consumption of blast-furnace gas during the first stage, reduce time required to bring the dome up to prescribed temperatures, shorten the stove-heating period, and increase blast-heating temperature by 10-15/degree/.

  20. Misconceptions of Emergent Semiconductor Phenomena

    NASA Astrophysics Data System (ADS)

    Nelson, Katherine G.

    The semiconductor field of Photovoltaics (PV) has experienced tremendous growth, requiring curricula to consider ways to promote student success. One major barrier to success students may face when learning PV is the development of misconceptions. The purpose of this work was to determine the presence and prevalence of misconceptions students may have for three PV semiconductor phenomena; Diffusion, Drift and Excitation. These phenomena are emergent, a class of phenomena that have certain characteristics. In emergent phenomena, the individual entities in the phenomena interact and aggregate to form a self-organizing pattern that can be observed at a higher level. Learners develop a different type of misconception for these phenomena, an emergent misconception. Participants (N=41) completed a written protocol. The pilot study utilized half of these protocols (n = 20) to determine the presence of both general and emergent misconceptions for the three phenomena. Once the presence of both general and emergent misconceptions was confirmed, all protocols (N=41) were analyzed to determine the presence and prevalence of general and emergent misconceptions, and to note any relationships among these misconceptions (full study). Through written protocol analysis of participants' responses, numerous codes emerged from the data for both general and emergent misconceptions. General and emergent misconceptions were found in 80% and 55% of participants' responses, respectively. General misconceptions indicated limited understandings of chemical bonding, electricity and magnetism, energy, and the nature of science. Participants also described the phenomena using teleological, predictable, and causal traits, indicating participants had misconceptions regarding the emergent aspects of the phenomena. For both general and emergent misconceptions, relationships were observed between similar misconceptions within and across the three phenomena, and differences in misconceptions were observed across the phenomena. Overall, the presence and prevalence of both general and emergent misconceptions indicates that learners have limited understandings of the physical and emergent mechanisms for the phenomena. Even though additional work is required, the identification of specific misconceptions can be utilized to enhance semiconductor and PV course content. Specifically, changes can be made to curriculum in order to limit the formation of misconceptions as well as promote conceptual change.

  1. A mouse model of ocular blast injury that induces closed globe anterior and posterior pole damage

    PubMed Central

    Hines-Beard, Jessica; Marchetta, Jeffrey; Gordon, Sarah; Chaum, Edward; Geisert, Eldon E.; Rex, Tonia S.

    2012-01-01

    We developed and characterized a mouse model of primary ocular blast injury. The device consists of: a pressurized air tank attached to a regulated paintball gun with a machined barrel; a chamber that protects the mouse from direct injury and recoil, while exposing the eye; and a secure platform that enables fine, controlled movement of the chamber in relation to the barrel. Expected pressures were calculated and the optimal pressure transducer, based on the predicted pressures, was positioned to measure output pressures at the location where the mouse eye would be placed. Mice were exposed to one of three blast pressures (23.6, 26.4, or 30.4psi). Gross pathology, intraocular pressure, optical coherence tomography, and visual acuity were assessed 0, 3, 7, 14, and 28 days after exposure. Contralateral eyes and non-blast exposed mice were used as controls. We detected increased damage with increased pressures and a shift in the damage profile over time. Gross pathology included corneal edema, corneal abrasions, and optic nerve avulsion. Retinal damage was detected by optical coherence tomography and a deficit in visual acuity was detected by optokinetics. Our findings are comparable to those identified in Veterans of the recent wars with closed eye injuries as a result of blast exposure. In summary, this is a relatively simple system that creates injuries with features similar to those seen in patients with ocular blast trauma. This is an important new model for testing the short-term and long-term spectrum of closed globe blast injuries and potential therapeutic interventions. PMID:22504073

  2. Performance of some coupling methods for blast vibration monitoring

    NASA Astrophysics Data System (ADS)

    Segarra, P.; Sanchidrián, J. A.; Castedo, R.; López, L. M.; del Castillo, I.

    2015-01-01

    Field guidelines and recommendations for blasting vibration monitoring on a hard surface, suggest that the geophone mount should be coupled to the ground in a way that depends on the anticipated vibration level. However, the quantitative performance of the coupling method is basically unknown. In order to investigate this, the ground-to-mount coupling transmissibility (i.e. ratio of the response of the geophones mount to the rock motion, as a function of frequency) was measured between 16 and 200 Hz in 43 tests using a vibration exciter. The geophone mounts were freely placed, hold with a sandbag and anchored on granite. Free placed mounts applied outside the suggested range of vibrations (i.e. frequencies above 50-70 Hz at 5 mm/s) lead to the largest expected errors (up to 7.5 dB). Distortion is still significant (1.02 dB), though to a minor degree, at lower levels where this method is recommended. Sandbagging limits the maximum expected error to 1.6 dB, but it is ranked as the worst method irrespective of the vibration level and the sandbag planting at frequencies below 40 Hz. Anchoring appears as the only analyzed method that achieves a stiff rock-to-mount coupling, ensuring consistent measurements for the frequencies commonly found in blasting independently of the vibration level and the mount characteristics.

  3. Ordering Phenomena in Undercooled Alloys

    SciTech Connect

    Fultz, Brent

    1997-07-17

    Much of the work performed under this grant was devoted to using modern ideas in kinetics to understand atom movements in metallic alloys far from thermodynamic equilibrium. Kinetics arguments were based explicitly on the vacancy mechanism for atom movements. The emphasis was on how individual atom movements are influenced by the local chemical environment of the moving atom, and how atom movements cause changes in the local chemical environments. The author formulated a kinetic master equation method to treat atom movements on a crystal lattice with a vacancy mechanism. Some of these analyses [3,10,16] are as detailed as any treatment of the statistical kinetics of atom movements in crystalline alloys. Three results came from this work. Chronologically they were (1) A recognition that tracking time dependencies is not necessarily the best way to study kinetic phenomena. If multiple order parameters can be measured in a material, the ''kinetic path'' through the space spanned by these order parameters maybe just as informative about the chemical factors that affect atom movements [2,3,5-7,9-11,14-16,18,19,21,23,24,26,36,37]. (2) Kinetic paths need not follow the steepest gradient of the free energy function (this should be well-known), and for alloys far from equilibrium the free energy function can be almost useless in describing kinetic behavior. This is why the third result surprised me. (3) In cluster approximations with multiple order parameters, saddle points are common features of free energy functions. Interestingly, kinetic processes stall or change time scale when the kinetic path approaches a state at a saddle point in the free energy function, even though these states exist far from thermodynamic equilibrium. The author calls such a state a ''pseudostable'' (falsely stable) state [6,21,26]. I have also studied these phenomena by more ''exact'' Monte Carlo simulations. The kinetic paths showed features similar to those found in analytical theories. The author found that a microstructure with interfaces arranged in space as a periodic minimal surface is a probably an alloy at a saddle point in its free energy function [21,26,37].

  4. The design, implementation, and evaluation of mpiBLAST

    SciTech Connect

    Darling, A. E. (Aaron E.); Carey, L. (Lucas); Feng, W. C. (Wu-Chun)

    2003-01-01

    mpiBLAST is an open-source parallelization of BLAST that achieves superlinear speed-up by segmenting a BLAST database and then having each node in a computational cluster search a unique portion of the database. Database segmentation permits each node to search a smaller portion of the database, eliminating disk I/O and vastly improving BLAST performance. Because database segmentation does not create heavy communication demands, BLAST users can take advantage of low-cost and efficient Linux cluster architectures such as the bladed Beowulf. In addition to presenting the software architecture of mpiBLAST we present a detailed performance analysis of mpiBLAST to demonstrate its scalability.

  5. LTC American`s, Inc. vacuum blasting machine: Baseline report

    SciTech Connect

    NONE

    1997-07-31

    The LTC shot blast technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The LTC 1073 Vacuum Blasting Machine uses a high-capacity, direct-pressure blasting system which incorporates a continuous feed for the blast media. The blast media cleans the surface within the contained brush area of the blast. It incorporates a vacuum system which removes dust and debris from the surface as it is blasted. The safety and health evaluation during the testing focused on two main areas of exposure: dust and noise.

  6. Vacuum arc recovery phenomena

    Microsoft Academic Search

    J. A. Rich; G. A. Farrall

    1964-01-01

    The present experimental and theoretical study has been designed to uncover the mechanism underlying the rapid recovery of electrical strength of a short vacuum gap after arcing. In the experiment the contacts were of gas-free silver and the contact area and gap length were varied. Recovery strength was measured following the forced extinction of a 250 amp arc in 0.5

  7. Topographic control on pyroclastic density currents: the example of Mount St. Helens 1980 blast

    NASA Astrophysics Data System (ADS)

    Esposti Ongaro, T.; Clarke, A. B.; Voight, B.; Neri, A.; Widiwijayanti, C.

    2012-04-01

    Volcanic lateral blasts are among the most spectacular and devastating of natural phenomena, characterized by the violent release of a relatively low mass of magma producing a remarkably broad area of significant damage. The most known volcanic blast at Mount Saint Helens, on 18 May 1980, devastated an area of 600 squared km in about five minutes, being able to override topographic obstacles of several hundreds of metres. By means of 3D multiphase numerical simulations we demonstrate that Mount St. Helens blast was generated by the rapid expansion (burst) of a pressurized polydisperse mixture of gas and particles and its subsequent gravitational collapse and that the observed front propagation, final runout and damage can be explained by the emplacement of an unsteady, stratified pyroclastic density current (PDC), controlled by gravity and terrain morphology. Numerical results are able to describe the non-equilibrium sedimentation dynamics of volcanic particles during PDC propagation across the rugged topography characterizing the area devastated by the blast. In valleys and topographic lows, pyroclasts accumulate progressively at the base of the flow, after the passage of the flow head, forming a dense basal flow depleted in fines. Blocking and channelling of such basal flow by topographic ridges provides the mechanism for progressive current unloading. On ridges, sedimentation occurs from the upper, dilute wake region, which follows the current head. Although the model formulation and the vertical numerical resolution do not yet allow the direct simulation of the deposit consolidation, present results provide a consistent, quantitative model able to interpret the observed stratigraphic sequence.

  8. Global efforts in managing rice blast disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease caused by the fungus Magnaporthe oryzae is a major destructive disease threatening global food security. Resistance (R) genes to M. oryzae are effective in preventing infections by strains of M. oryzae carry the corresponding avirulence (AVR) genes. Effectiveness of genetic resist...

  9. Rice blast evaluation of newly introduced germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic resistance to the rice blast fungus, Magnaporthe oryzae (anamorph Pyricularia grisea oryzae) was identified in newly introduced rice germplasm through quarantine when tested in artificially inoculated greenhouse and field nursery tests during the 2007 growing season. Of 229 accessions, 31 we...

  10. The polar bear phenomena

    SciTech Connect

    Maw, P.K. (United Kingdom Ingersoll-Rand Sales Company, Ltd., Horwich, Bolton Lancashire, BL6 6JN (GB)); Lane, M.T.

    1990-02-01

    Results from measuring the thermal profile of polar bear pelts, reflectiveness of the pelts, and total thermal conversion data lead to the conclusion that the pelts from an ultra-efficient thermal diode for solar-thermal conversion. The transfer of the thermal energy from the surface of the fur to the skin where it is absorbed cannot be thermal, and therefore must be radiative. This process must have an efficiency of better than 90:0090 percent to account for measured values. The radiative transfer process is not known at present. To understand it, a detailed knowledge of the microscopic parameters of the pelts must be obtained. This is the current thrust of the polar solar research. If the process can be understood and synthesized,it will provide a major breakthrough in the area of solar-thermal energy conversion.

  11. Distinguishing Realistic Military Blasts from Firecrackers in Mitigation Studies of Blast Induced Traumatic Brain Injury

    SciTech Connect

    Moss, W C; King, M J; Blackman, E G

    2011-01-21

    In their Contributed Article, Nyein et al. (1,2) present numerical simulations of blast waves interacting with a helmeted head and conclude that a face shield may significantly mitigate blast induced traumatic brain injury (TBI). A face shield may indeed be important for future military helmets, but the authors derive their conclusions from a much smaller explosion than typically experienced on the battlefield. The blast from the 3.16 gm TNT charge of (1) has the following approximate peak overpressures, positive phase durations, and incident impulses (3): 10 atm, 0.25 ms, and 3.9 psi-ms at the front of the head (14 cm from charge), and 1.4 atm, 0.32 ms, and 1.7 psi-ms at the back of a typical 20 cm head (34 cm from charge). The peak pressure of the wave decreases by a factor of 7 as it traverses the head. The blast conditions are at the threshold for injury at the front of the head, but well below threshold at the back of the head (4). The blast traverses the head in 0.3 ms, roughly equal to the positive phase duration of the blast. Therefore, when the blast reaches the back of the head, near ambient conditions exist at the front. Because the headform is so close to the charge, it experiences a wave with significant curvature. By contrast, a realistic blast from a 2.2 kg TNT charge ({approx} an uncased 105 mm artillery round) is fatal at an overpressure of 10 atm (4). For an injury level (4) similar to (1), a 2.2 kg charge has the following approximate peak overpressures, positive phase durations, and incident impulses (3): 2.1 atm, 2.3 ms, and 18 psi-ms at the front of the head (250 cm from charge), and 1.8 atm, 2.5 ms, and 16.8 psi-ms at the back of the head (270 cm from charge). The peak pressure decreases by only a factor of 1.2 as it traverses the head. Because the 0.36 ms traversal time is much smaller than the positive phase duration, pressures on the head become relatively uniform when the blast reaches the back of the head. The larger standoff implies that the headform locally experiences a nearly planar blast wave. Also, the positive phase durations and blast impulses are much larger than those of (1). Consequently, the blast model used in (1) is spatially and temporally very different from a military blast. It would be useful to repeat the calculations using military blast parameters. Finally, (1) overlooks a significant part of (5). On page 1 and on page 3, (1) states that (5) did not consider helmet pads. But pages pages 3 and 4 of (5) present simulations of blast wave propagation across an ACH helmeted head form with and without pads. (5) states that when the pads are present, the 'underwash' of air under the helmet is blocked when compared to the case without. (1) reaches this same conclusion, but reports it as a new result rather than a confirmation of that already found in (5).

  12. Considerations for animal models of blast-related traumatic brain injury and chronic traumatic encephalopathy.

    PubMed

    Goldstein, Lee E; McKee, Ann C; Stanton, Patric K

    2014-01-01

    The association of military blast exposure and brain injury was first appreciated in World War I as commotio cerebri, and later as shell shock. Similar injuries sustained in modern military conflicts are now classified as mild traumatic brain injury (TBI). Recent research has yielded new insights into the mechanisms by which blast exposure leads to acute brain injury and chronic sequelae, including postconcussive syndrome, post-traumatic stress disorder, post-traumatic headache, and chronic traumatic encephalopathy, a tau protein neurodegenerative disease. Impediments to delivery of effective medical care for individuals affected by blast-related TBI include: poor insight into the heterogeneity of neurological insults induced by blast exposure; limited understanding of the mechanisms by which blast exposure injures the brain and triggers sequelae; failure to appreciate interactive injuries that affect frontal lobe function, pituitary regulation, and neurovegetative homeostasis; unknown influence of genetic risk factors, prior trauma, and comorbidities; absence of validated diagnostic criteria and clinical nosology that differentiate clinical endophenotypes; and lack of empirical evidence to guide medical management and therapeutic intervention. While clinicopathological analysis can provide evidence of correlative association, experimental use of animal models remains the primary tool for establishing causal mechanisms of disease. However, the TBI field is confronted by a welter of animal models with varying clinical relevance, thereby impeding scientific coherence and hindering translational progress. Animal models of blast TBI will be far more translationally useful if experimental emphasis focuses on accurate reproduction of clinically relevant endpoints (output) rather than scaled replication of idealized blast shockwaves (input). The utility of an animal model is dependent on the degree to which the model recapitulates pathophysiological mechanisms, neuropathological features, and neurological sequelae observed in the corresponding human disorder. Understanding the purpose of an animal model and the criteria by which experimental results derived from the model are validated are critical components for useful animal modeling. Animal models that reliably demonstrate clinically relevant endpoints will expedite development of new treatments, diagnostics, preventive measures, and rehabilitative strategies for individuals affected by blast TBI and its aftermath. PMID:25478023

  13. Considerations for animal models of blast-related traumatic brain injury and chronic traumatic encephalopathy

    PubMed Central

    2014-01-01

    The association of military blast exposure and brain injury was first appreciated in World War I as commotio cerebri, and later as shell shock. Similar injuries sustained in modern military conflicts are now classified as mild traumatic brain injury (TBI). Recent research has yielded new insights into the mechanisms by which blast exposure leads to acute brain injury and chronic sequelae, including postconcussive syndrome, post-traumatic stress disorder, post-traumatic headache, and chronic traumatic encephalopathy, a tau protein neurodegenerative disease. Impediments to delivery of effective medical care for individuals affected by blast-related TBI include: poor insight into the heterogeneity of neurological insults induced by blast exposure; limited understanding of the mechanisms by which blast exposure injures the brain and triggers sequelae; failure to appreciate interactive injuries that affect frontal lobe function, pituitary regulation, and neurovegetative homeostasis; unknown influence of genetic risk factors, prior trauma, and comorbidities; absence of validated diagnostic criteria and clinical nosology that differentiate clinical endophenotypes; and lack of empirical evidence to guide medical management and therapeutic intervention. While clinicopathological analysis can provide evidence of correlative association, experimental use of animal models remains the primary tool for establishing causal mechanisms of disease. However, the TBI field is confronted by a welter of animal models with varying clinical relevance, thereby impeding scientific coherence and hindering translational progress. Animal models of blast TBI will be far more translationally useful if experimental emphasis focuses on accurate reproduction of clinically relevant endpoints (output) rather than scaled replication of idealized blast shockwaves (input). The utility of an animal model is dependent on the degree to which the model recapitulates pathophysiological mechanisms, neuropathological features, and neurological sequelae observed in the corresponding human disorder. Understanding the purpose of an animal model and the criteria by which experimental results derived from the model are validated are critical components for useful animal modeling. Animal models that reliably demonstrate clinically relevant endpoints will expedite development of new treatments, diagnostics, preventive measures, and rehabilitative strategies for individuals affected by blast TBI and its aftermath. PMID:25478023

  14. Patterns in Blast Injuries to the Hand

    PubMed Central

    Buntic, Rudolf F.; Brooks, Darrell

    2008-01-01

    Blast injuries to the hand are not just a wartime phenomenon but also quite common in rural communities throughout northern California. The purpose of this study is to review our experience with blast injuries in the community and review the most common patterns in an attempt to identify the pathomechanics of the hand injury and the reconstructive procedures that are required. This is a retrospective study of blast injuries to the hand treated between 1978 and 2006. Medical records, X-rays, and photos were reviewed to compile standard patient demographics and characterize the injury pattern. Explosives were classified based on their rate of decomposition. Reconstructive solutions were reviewed and characterized based on whether damaged tissues were repaired or replaced. Sixty-two patients were identified with blast injuries to their hand. Patients were predominantly male (92%) with an average age of 27 years. Firecrackers were the most commonly encountered explosives. Thirty-seven patients were identified as holding a low explosive in their dominant hand and were used for characterization of the injury pattern. The apparent pattern of injury was hyperextension and hyperabduction of the hand and digits. Common injuries were metacarpophalangeal and interphalangeal joint hyperextension with associated soft tissue avulsion, hyperabduction at the web spaces with associated palmar soft tissue tears, and finger disarticulation amputations worse at radial digits. Given the mechanisms of injury with tissue loss, surgical intervention generally involved tissue replacement rather than tissue repair. Blast injuries to the hand represent a broad spectrum of injuries that are associated with the magnitude of explosion and probably, the proximity to the hand. We were able to identify a repetitive pattern of injury and demonstrate the predominant use for delayed tissue replacement rather than microsurgical repair at the acute setting. PMID:18780004

  15. Droplet Breakup Mechanisms in Air-blast Atomizers

    NASA Astrophysics Data System (ADS)

    Aliabadi, Amir Abbas; Taghavi, Seyed Mohammad; Lim, Kelly

    2011-11-01

    Atomization processes are encountered in many natural and man-made phenomena. Examples are pollen release by plants, human cough or sneeze, engine fuel injectors, spray paint and many more. The physics governing the atomization of liquids is important in understanding and utilizing atomization processes in both natural and industrial processes. We have observed the governing physics of droplet breakup in an air-blast water atomizer using a high magnification, high speed, and high resolution LASER imaging technique. The droplet breakup mechanisms are investigated in three major categories. First, the liquid drops are flattened to form an oblate ellipsoid (lenticular deformation). Subsequent deformation depends on the magnitude of the internal forces relative to external forces. The ellipsoid is converted into a torus that becomes stretched and disintegrates into smaller drops. Second, the drops become elongated to form a long cylindrical thread or ligament that break up into smaller drops (Cigar-shaped deformation). Third, local deformation on the drop surface creates bulges and protuberances that eventually detach themselves from the parent drop to form smaller drops.

  16. Spike morphology in blast-wave-driven instability experiments

    SciTech Connect

    Kuranz, C. C.; Drake, R. P.; Grosskopf, M. J.; Fryxell, B.; Budde, A. [Department of Atmospheric, Oceanic and Space Science, Center for Radiative Shock Hydrodynamics, University of Michigan, 2455 Hayward Street, Ann Arbor, Michigan 48109 (United States); Hansen, J. F.; Miles, A. R. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Plewa, T. [Department of Scientific Computing, Florida State University, 400 Dirac Science Library, Tallahassee, Florida 32306 (United States); Hearn, N. [Center for Astrophysical Thermonuclear Flashes, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637 (United States); Knauer, J. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States)

    2010-05-15

    The laboratory experiments described in the present paper observe the blast-wave-driven Rayleigh-Taylor instability with three-dimensional (3D) initial conditions. About 5 kJ of energy from the Omega laser creates conditions similar to those of the He-H interface during the explosion phase of a supernova. The experimental target is a 150 {mu}m thick plastic disk followed by a low-density foam. The plastic piece has an embedded, 3D perturbation. The basic structure of the pattern is two orthogonal sine waves where each sine wave has an amplitude of 2.5 {mu}m and a wavelength of 71 {mu}m. In some experiments, an additional wavelength is added to explore the interaction of modes. In experiments with 3D initial conditions the spike morphology differs from what has been observed in other Rayleigh-Taylor experiments and simulations. Under certain conditions, experimental radiographs show some mass extending from the interface to the shock front. Current simulations show neither the spike morphology nor the spike penetration observed in the experiments. The amount of mass reaching the shock front is analyzed and potential causes for the spike morphology and the spikes reaching the shock are discussed. One such hypothesis is that these phenomena may be caused by magnetic pressure, generated by an azimuthal magnetic field produced by the plasma dynamics.

  17. Lessons learned from the analysis of soldier collected blast data.

    PubMed

    Fain, W Bradley; Phelps, Shean; Medda, Alessio

    2015-03-01

    In recent U.S. military experience, widespread exposure to improvised explosive devices has been implicated in noticeable changes in the incidence of brain injuries inversely related to reduced mortality-thought to be the unintended consequence of increase in exposure to blast wave effects-secondary to improved vital organ protection, improved personal protective equipment. Subsequently, there is a growing need for the development and fielding of fully integrated sensor systems capable of both capturing dynamic effects (i.e., "blast") on the battlefield-providing critical information for researchers, while providing value to the medical community and leaders-for development of pre-emptive measures and policies. Obtaining accurate and useful data remains a significant challenge with a need for sensors which feed systems that provide accurate interpretation of dynamic events and lend to an enhanced understanding of their significance to the individual. This article describes lessons learned from a data analysis perspective of a collaborative effort led by a team formed at Georgia Tech Research Institute to develop a "sensor agnostic" system that demonstrates full integration across variant platforms/systems. The system is designed to allow digital and analog time/frequency data synchronization and analysis, which facilitated the development of complex multimodal modeling/algorithms. PMID:25747654

  18. Critical phenomena in complex networks

    E-print Network

    S. N. Dorogovtsev; A. V. Goltsev; J. F. F. Mendes

    2007-11-16

    The combination of the compactness of networks, featuring small diameters, and their complex architectures results in a variety of critical effects dramatically different from those in cooperative systems on lattices. In the last few years, researchers have made important steps toward understanding the qualitatively new critical phenomena in complex networks. We review the results, concepts, and methods of this rapidly developing field. Here we mostly consider two closely related classes of these critical phenomena, namely structural phase transitions in the network architectures and transitions in cooperative models on networks as substrates. We also discuss systems where a network and interacting agents on it influence each other. We overview a wide range of critical phenomena in equilibrium and growing networks including the birth of the giant connected component, percolation, k-core percolation, phenomena near epidemic thresholds, condensation transitions, critical phenomena in spin models placed on networks, synchronization, and self-organized criticality effects in interacting systems on networks. We also discuss strong finite size effects in these systems and highlight open problems and perspectives.

  19. Blast furnace slags as sorbents of phosphate from water solutions.

    PubMed

    Kostura, Bruno; Kulveitová, Hana; Lesko, Juraj

    2005-05-01

    The paper is focused on the sorption of phosphorus from aqueous solutions by crystalline and amorphous blast furnace slags. Slag sorption kinetics were measured, adsorption tests were carried out and the effect of acidification on the sorption properties of slags was studied. The kinetic measurements confirmed that the sorption of phosphorus on crystalline as well as amorphous slags can be described by a model involving pseudo-second-order reactions. For all slag types, phosphorus sorption follows the Langmuir adsorption isotherm. The acid neutralizing capacities of crystalline and amorphous slags were determined. In the case of the crystalline slags, buffering intervals were found to exist during which the slag minerals dissolve in the sequence bredigite-gehlenite-diaspor. There is a high correlation (R2=0.9989) between ANC3.8 and the saturation capacities of crystalline and amorphous slags. PMID:15899277

  20. Shock Tube Design for High Intensity Blast Waves for Laboratory Testing of Armor and Combat Materiel

    E-print Network

    Courtney, Elijah; Courtney, Michael

    2015-01-01

    Shock tubes create simulated blast waves which can be directed and measured to study blast wave effects under laboratory conditions. It is desirable to increase available peak pressure from ~1 MPa to ~5 MPa to simulate closer blast sources and facilitate development and testing of personal and vehicle armors. Three methods were investigated to increase peak simulated blast pressure produced by an oxy-acetylene driven shock tube while maintaining suitability for laboratory studies. The first method is the addition of a Shchelkin spiral priming section which works by increasing the turbulent flow of the deflagration wave, thus increasing its speed and pressure. This approach increased the average peak pressure from 1.17 MPa to 5.33 MPa while maintaining a relevant pressure-time curve (Friedlander waveform). The second method is a bottleneck between the driving and driven sections. Coupling a 79 mm diameter driving section to a 53 mm driven section increased the peak pressure from 1.17 MPa to 2.25 MPa. Using a 1...

  1. Physics of IED Blast Shock Tube Simulations for mTBI Research

    PubMed Central

    Mediavilla Varas, Jesus; Philippens, M.; Meijer, S. R.; van den Berg, A. C.; Sibma, P. C.; van Bree, J. L. M. J.; de Vries, D. V. W. M.

    2011-01-01

    Shock tube experiments and simulations are conducted with a spherical gelatin filled skull–brain surrogate, in order to study the mechanisms leading to blast induced mild traumatic brain injury. A shock tube including sensor system is optimized to simulate realistic improvised explosive device blast profiles obtained from full scale field tests. The response of the skull–brain surrogate is monitored using pressure and strain measurements. Fluid–structure interaction is modeled using a combination of computational fluid dynamics (CFD) simulations for the air blast, and a finite element model for the structural response. The results help to understand the physics of wave propagation, from air blast into the skull–brain. The presence of openings on the skull and its orientation does have a strong effect on the internal pressure. A parameter study reveals that when there is an opening in the skull, the skull gives little protection and the internal pressure is fairly independent on the skull stiffness; the gelatin shear stiffness has little effect on the internal pressure. Simulations show that the presence of pressure sensors in the gelatin hardly disturbs the pressure field. PMID:21960984

  2. NO x emissions from blasting operations in open-cut coal mining

    NASA Astrophysics Data System (ADS)

    Attalla, Moetaz I.; Day, Stuart J.; Lange, Tony; Lilley, William; Morgan, Scott

    The Australian coal mining industry, as with other industries is coming under greater constraints with respect to their environmental impacts. Emissions of acid gases such as NO x and SO x to the atmosphere have been regulated for many years because of their adverse health effects. Although NO x from blasting in open-cut coal mining may represent only a very small proportion of mining operations' total NO x emissions, the rapid release and high concentration associated with such activities may pose a health risk. This paper presents the results of a new approach to measure these gas emissions by scanning the resulting plume from an open-cut mine blast with a miniaturised ultraviolet spectrometer. The work presented here was undertaken in the Hunter Valley, New South Wales, Australia during 2006. Overall this technique was found to be simpler, safer and more successful than other approaches that in the past have proved to be ineffective in monitoring these short lived plumes. The average emission flux of NO x from the blasts studied was about 0.9 kt t -1 of explosive. Numerical modelling indicated that NO x concentrations resulting from the blast would be indistinguishable from background levels at distances greater than about 5 km from the source.

  3. 30 CFR 56.6200 - Delivery to storage or blast site areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Delivery to storage or blast site areas. 56.6200 Section 56... § 56.6200 Delivery to storage or blast site areas. Explosive material shall...without undue delay to the storage area or blast...

  4. 30 CFR 817.68 - Use of explosives: Records of blasting operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... The operator shall retain a record of all blasts for at least 3 years. Upon request, copies... (a) Name of the operator conducting the blast. (b) Location, date, and time of the blast. (c) Name, signature, and...

  5. 14 CFR 417.229 - Far-field overpressure blast effects analysis.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Far-field overpressure blast effects analysis. 417.229 Section... § 417.229 Far-field overpressure blast effects analysis. (a) General. ...from any hazard associated with far field blast overpressure effects due to...

  6. 30 CFR 816.68 - Use of explosives: Records of blasting operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... The operator shall retain a record of all blasts for at least 3 years. Upon request, copies... (a) Name of the operator conducting the blast. (b) Location, date, and time of the blast. (c) Name, signature, and...

  7. 30 CFR 57.6200 - Delivery to storage or blast site areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Delivery to storage or blast site areas. 57.6200 Section 57... § 57.6200 Delivery to storage or blast site areas. Explosive material shall...without undue delay to the storage area or blast...

  8. Modeling of Human Brain Tissues and Head Injuries Induced by Blast and Ballistic Impact

    E-print Network

    Kulkarni, Sahil G

    2013-11-07

    is developed to study non-penetrating TBI. The effects of constitutive models and blast directions on finite elements simulations of blast induced TBI are investigated. Further, the effectiveness of combat helmets against non-penetrating TBI induced by blast...

  9. Dosage-response relationships for community annoyance with blasting

    SciTech Connect

    Fidell, S.; Horonjeff, R.

    1982-01-01

    This paper summarizes a study of community response to blasting at two coal mines and a quarry. Over 1000 people were interviewed to determine the prevalence (that is, both intensity and extensity) of annoyance associated with long term exposure to ground vibration and airblast at distances from about 500 to 4000 meters from blasting sites. The sites were chosen, among other reasons, for their lack of unusual geologic conditions, and for the historical continuity and range of blasting activity (frequencies of blasting of two or three shots per week or less, and maximum charge weights per delay ranging from about 100 to 10,000 pounds). A major goal of this study was to attempt to infer dosage-response relationships between long term exposure to blasting and the proportion of the community highly annoyed by the blasting.

  10. Transport Phenomena and Materials Processing

    NASA Astrophysics Data System (ADS)

    Kou, Sindo

    1996-10-01

    An extremely useful guide to the theory and applications of transport phenomena in materials processing This book defines the unique role that transport phenomena play in materials processing and offers a graphic, comprehensive treatment unlike any other book on the subject. The two parts of the text are, in fact, two useful books. Part I is a very readable introduction to fluid flow, heat transfer, and mass transfer for materials engineers and anyone not yet thoroughly familiar with the subject. It includes governing equations and boundary conditions particularly useful for studying materials processing. For mechanical and chemical engineers, and anyone already familiar with transport phenomena, Part II covers the many specific applications to materials processing, including a brief description of various materials processing technologies. Readable and unencumbered by mathematical manipulations (most of which are allocated to the appendixes), this book is also a useful text for upper-level undergraduate and graduate-level courses in materials, mechanical, and chemical engineering. It includes hundreds of photographs of materials processing in action, single and composite figures of computer simulation, handy charts for problem solving, and more. Transport Phenomena and Materials Processing: * Describes eight key materials processing technologies, including crystal growth, casting, welding, powder and fiber processing, bulk and surface heat treating, and semiconductor device fabrication * Covers the latest advances in the field, including recent results of computer simulation and flow visualization * Presents special boundary conditions for transport phenomena in materials processing * Includes charts that summarize commonly encountered boundary conditions and step-by-step procedures for problem solving * Offers a unique derivation of governing equations that leads to both overall and differential balance equations * Provides a list of publicly available computer programs and publications relevant to transport phenomena in materials processing

  11. Scaling law in thermal phenomena

    E-print Network

    M. Kozlowski; J. Marciak-Kozlowska

    2006-10-29

    In this paper the scaling law for the relaxation times in thermal phenomena is investigated. It is shown that dependent on the value of the parameter K=E/m(c\\alpha)^2,where E is the energy which is delivered to the system, m is the parton mass and \\alpha=1/137 for electromagnetic interaction and \\alpha=0.16 for strong interaction respectively, heat transport is diffusive, for K1. For the system with N partons the relaxation time is scaled as \\tau^N\\to N (\\hbar/(mc\\alpha)^2). Key words: Thermal phenomena, scaling

  12. Abnormal pressures as hydrodynamic phenomena

    USGS Publications Warehouse

    Neuzil, C.E.

    1995-01-01

    So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

  13. A Phased Array Approach to Rock Blasting

    SciTech Connect

    Leslie Gertsch; Jason Baird

    2006-07-01

    A series of laboratory-scale simultaneous two-hole shots was performed in a rock simulant (mortar) to record the shock wave interference patterns produced in the material. The purpose of the project as a whole was to evaluate the usefulness of phased array techniques of blast design, using new high-precision delay technology. Despite high-speed photography, however, we were unable to detect the passage of the shock waves through the samples to determine how well they matched the expected interaction geometry. The follow-up mine-scale tests were therefore not conducted. Nevertheless, pattern analysis of the vectors that would be formed by positive interference of the shockwaves from multiple charges in an ideal continuous, homogeneous, isotropic medium indicate the potential for powerful control of blast design, given precise characterization of the target rock mass.

  14. Fatigue of a glass bead blasted nickel-base superalloy

    Microsoft Academic Search

    L. H. Burck; C. P. Sullivan; C. H. Wells

    1970-01-01

    Room temperature fatigue crack initiation and propagation in the wrought nickel-base superalloy Udimet 700 were investigated\\u000a with electropolished and glass bead blasted material. Cracks were found to initiate at the surface along coherent annealing\\u000a twin boundaries oriented for maximum in-plane shear stress in both the electropolished and glass bead blasted conditions even\\u000a though bead blasting more than doubled the fatigue

  15. Developments in vapour cloud explosion blast modeling.

    PubMed

    Mercx, W P; van den Berg, A C; Hayhurst, C J; Robertson, N J; Moran, K C

    2000-01-01

    TNT Equivalency methods are widely used for vapour cloud explosion blast modeling. Presently, however, other types of models are available which do not have the fundamental objections TNT Equivalency models have. TNO Multi-Energy method is increasingly accepted as a more reasonable alternative to be used as a simple and practical method. Computer codes based on computational fluid dynamics (CFD) like AutoReaGas, developed by TNO and Century Dynamics, could be used also in case a more rigorous analysis is required. Application of the Multi-Energy method requires knowledge of two parameters describing the explosion: a charge size and a charge strength. During the last years, research has led to an improved determination of the charge strength (i.e., the class number or source overpressure) to be chosen to apply the blast charts. A correlation has been derived relating the charge strength to a set of parameters describing the boundary conditions of the flammable cloud and the fuel in the cloud. A simple approach may not be satisfactory in all situations. The overpressure distribution inside a vapour cloud explosion is generally not homogeneous and the presence of obstructions causes directional blast propagation in the near field. A CFD approach, in which the actual situation is modeled, supplies case-specific results. An overview of the key aspects relevant to the application of the Multi-Energy method and CFD modeling is provided. Then the application of the two methods is demonstrated for an example problem involving the calculation of the explosion blast load on a structure at some distance from the explosion in an offshore platform complex. PMID:10677667

  16. Blast wave simulation with ground surface effect

    NASA Astrophysics Data System (ADS)

    Fujii, Kozo; Shimizu, Fumio; Tamura, Yoshiaki; Higashino, Fumio; Hinada, Motoki; Akiba, Ryojiro

    Unsteady flowfield generated by the finite strength of a shock wave is computationally simulated with the discretization method. The results indicate that the overpressure depends on the ground surface geometry as well as the distance from the point of explosion. The present approach using the new computational-fluid-dynamic technology may improve the existing theory for estimating the unsteady motion and decay of blast waves and eventually lead to better estimation of the safety distance for rocket launching.

  17. Explosive parcel containment and blast mitigation container

    DOEpatents

    Sparks, Michael H. (Frederick County, MD)

    2001-06-12

    The present invention relates to a containment structure for containing and mitigating explosions. The containment structure is installed in the wall of the building and has interior and exterior doors for placing suspicious packages into the containment structure and retrieving them from the exterior of the building. The containment structure has a blast deflection chute and a blowout panel to direct over pressure from explosions away from the building, surrounding structures and people.

  18. Boundary-layer theory for blast waves

    NASA Technical Reports Server (NTRS)

    Kim, K. B.; Berger, S. A.; Kamel, M. M.; Korobeinikov, V. P.; Oppenheim, A. K.

    1975-01-01

    It is profitable to consider the blast wave as a flow field consisting of two regions: the outer, which retains the properties of the inviscid solution, and the inner, which is governed by flow equations including terms expressing the effects of heat transfer and, concomitantly, viscosity. The latter region thus plays the role of a boundary layer. Reported here is an analytical method developed for the study of such layers, based on the matched asymptotic expansion technique combined with patched solutions.

  19. Centrifugal shot blasting. Innovative technology summary report

    SciTech Connect

    Not Available

    1999-07-01

    At the US Department of Energy (DOE) Fernald Environmental Management Project (FEMP), the Facilities Closure and Demolition Projects Integrated Remedial Design/Remedial Action (RD/RA) work plan calls for the removal of one inch (1 in) depth of concrete surface in areas where contamination with technetium-99 has been identified. This report describes a comparative demonstration between two concrete removal technologies: an innovative system using Centrifugal Shot Blasting (CSB) and a modified baseline technology called a rotary drum planer.

  20. Metal sorption on blast-furnace slag

    Microsoft Academic Search

    S. V. Dimitrova

    1996-01-01

    The removal of Cu, Ni and Zn-ions from water solution by ungranulated blast-furnace slag has been studied depending on contact time, initial ion concentration, pH and solution temperature. The polymineral composition and the slag specific properties determine its high sorption activity in metal salts solutions. In the range of the concentrations studied (10?4–10?3 M), the sorption data for Cu2+, Ni2+

  1. Breakdown phenomena in high power klystrons

    SciTech Connect

    Vlieks, A.E.; Allen, M.A.; Callin, R.S.; Fowkes, W.R.; Hoyt, E.W.; Lebacqz, J.V.; Lee, T.G.

    1988-03-01

    In the course of developing new high peak power klystrons at SLAC, high electric fields in several regions of these devices have become an important source of vacuum breakdown phenomena. In addition, a renewed interest in breakdown phenomena for nanosecond pulse, multi-megavolt per centimeter fields has been sparked by recent R and D work in the area of gigawatt RF sources. The most important regions of electrical breakdown are in the output cavity gap area, the RF ceramic windows, and the gun ceramic insulator. The details of the observed breakdown in these regions, experiments performed to understand the phenomena and solutions found to alleviate the problems will be discussed. Recently experiments have been performed on a new prototype R and D klystron. Peak electric fields across the output cavity gaps of this klystron exceed 2 MV/cm. The effect of peak field duration (i.e. pulse width) on the onset of breakdown have been measured. The pulse widths varied from tens of nanoseconds to microseconds. Results from these experiments will be presented. The failure of ceramic RF windows due to multipactor and puncturing was an important problem to overcome in order that our high power klystrons would have a useful life expectancy. Consequently many studies and tests were made to understand and alleviate window breakdown phenomena. Some of the results in this area, especially the effects of surface coatings, window materials and processing techniques and their effects on breakdown will be discussed. Another important source of klystron failure in the recent past at SLAC has been the puncturing of the high voltage ceramic insulator in the gun region. A way of alleviating this problem has been found although the actual cause of the puncturing is not yet clear. The ''practical'' solution to this breakdown process will be described and a possible mechanism for the puncturing will be presented. 9 refs., 5 figs., 3 tabs.

  2. Mechanisms of Hearing Loss after Blast Injury to the Ear

    PubMed Central

    Cho, Sung-Il; Gao, Simon S.; Xia, Anping; Wang, Rosalie; Salles, Felipe T.; Raphael, Patrick D.; Abaya, Homer; Wachtel, Jacqueline; Baek, Jongmin; Jacobs, David; Rasband, Matthew N.; Oghalai, John S.

    2013-01-01

    Given the frequent use of improvised explosive devices (IEDs) around the world, the study of traumatic blast injuries is of increasing interest. The ear is the most common organ affected by blast injury because it is the body’s most sensitive pressure transducer. We fabricated a blast chamber to re-create blast profiles similar to that of IEDs and used it to develop a reproducible mouse model to study blast-induced hearing loss. The tympanic membrane was perforated in all mice after blast exposure and found to heal spontaneously. Micro-computed tomography demonstrated no evidence for middle ear or otic capsule injuries; however, the healed tympanic membrane was thickened. Auditory brainstem response and distortion product otoacoustic emission threshold shifts were found to be correlated with blast intensity. As well, these threshold shifts were larger than those found in control mice that underwent surgical perforation of their tympanic membranes, indicating cochlear trauma. Histological studies one week and three months after the blast demonstrated no disruption or damage to the intra-cochlear membranes. However, there was loss of outer hair cells (OHCs) within the basal turn of the cochlea and decreased spiral ganglion neurons (SGNs) and afferent nerve synapses. Using our mouse model that recapitulates human IED exposure, our results identify that the mechanisms underlying blast-induced hearing loss does not include gross membranous rupture as is commonly believed. Instead, there is both OHC and SGN loss that produce auditory dysfunction. PMID:23840874

  3. Mechanisms of hearing loss after blast injury to the ear.

    PubMed

    Cho, Sung-Il; Gao, Simon S; Xia, Anping; Wang, Rosalie; Salles, Felipe T; Raphael, Patrick D; Abaya, Homer; Wachtel, Jacqueline; Baek, Jongmin; Jacobs, David; Rasband, Matthew N; Oghalai, John S

    2013-01-01

    Given the frequent use of improvised explosive devices (IEDs) around the world, the study of traumatic blast injuries is of increasing interest. The ear is the most common organ affected by blast injury because it is the body's most sensitive pressure transducer. We fabricated a blast chamber to re-create blast profiles similar to that of IEDs and used it to develop a reproducible mouse model to study blast-induced hearing loss. The tympanic membrane was perforated in all mice after blast exposure and found to heal spontaneously. Micro-computed tomography demonstrated no evidence for middle ear or otic capsule injuries; however, the healed tympanic membrane was thickened. Auditory brainstem response and distortion product otoacoustic emission threshold shifts were found to be correlated with blast intensity. As well, these threshold shifts were larger than those found in control mice that underwent surgical perforation of their tympanic membranes, indicating cochlear trauma. Histological studies one week and three months after the blast demonstrated no disruption or damage to the intra-cochlear membranes. However, there was loss of outer hair cells (OHCs) within the basal turn of the cochlea and decreased spiral ganglion neurons (SGNs) and afferent nerve synapses. Using our mouse model that recapitulates human IED exposure, our results identify that the mechanisms underlying blast-induced hearing loss does not include gross membranous rupture as is commonly believed. Instead, there is both OHC and SGN loss that produce auditory dysfunction. PMID:23840874

  4. Mechanisms and Treatment of Blast Induced Hearing Loss

    PubMed Central

    2012-01-01

    The main objective of this study is to provide an overview of the basic mechanisms of blast induced hearing loss and review pharmacological treatments or interventions that can reduce or inhibit blast induced hearing loss. The mechanisms of blast induced hearing loss have been studied in experimental animal models mimicking features of damage or injury seen in human. Blast induced hearing loss is characterized by perforation and rupture of the tympanic membrane, ossicular damage, basilar membrane damage, inner and outer hair cell loss, rupture of round window, changes in chemical components of cochlear fluid, vasospasm, ischemia, oxidative stress, excitotoxicity, hematoma, and hemorrhage in both animals and humans. These histopathological consequences of blast exposure can induce hearing loss, tinnitus, dizziness, and headache. The pharmacological approaches to block or inhibit some of the auditory pathological consequences caused by blast exposure have been developed with antioxidant drugs such as 2,4-disulfonyl ?-phenyl tertiary butyl nitrone (HXY-059, now called HPN-07) and N-acetylcysteine (NAC). A combination of antioxidant drugs (HPN-07 and NAC) was administered to reduce blast induced cochlear damage and hearing loss. The combination of the antioxidant drugs can prevent or treat blast induced hearing loss by reducing damage to the mechanical and neural component of the auditory system. Although information of the underlying mechanisms and treatment of blast induced hearing loss are provided, further and deep research should be achieved due to the limited and controversial knowledge. PMID:24653882

  5. 13. BUILDING NO. 621, INTERIOR, TOP OF BLASTING TUB UNDERNEATH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. BUILDING NO. 621, INTERIOR, TOP OF BLASTING TUB UNDERNEATH SAWDUST HOPPER. BLASTING TUB HAS DOUBLE WALLS OF 3/4' THICK STEEL ARMOR PLATE. CHARGE TO BE TESTED IS BURIED IN SAWDUST WITH FLAME RESISTANT CHEMICALS. ELEVATOR BEHIND TUB CARRIES SAWDUST BACK TO TOP OF SAWDUST HOPPER AFTER TEST IS COMPLETED AND SAWDUST IN BLASTING TUB HAS BEEN SIFTED FOR SHELL FRAGMENTS. LOUVERS IN WALLS ARE HINGED FREELY SO THEY OPEN TO RELIEVE BLAST PRESSURE DURING A TEST. - Picatinny Arsenal, 600 Area, Test Areas District, State Route 15 near I-80, Dover, Morris County, NJ

  6. Brain injury from explosive blast: description and clinical management.

    PubMed

    Ling, G; Ecklund, J M; Bandak, F A

    2015-01-01

    Accumulating clinical experience is indicating that explosive blast brain injury is becoming recognized as a disease distinct from the penetrating form of blast injury as well as the classic closed head injury (CHI). In recent US conflicts in Iraq and Afghanistan, over 60% of combat casualties were from explosive blast with the hallmark explosive weapon being the improvised explosive device (IED). Explosive blast TBI is a condition afflicting many combat injured warfighters potentially constituting another category of TBI. Clinically, it shares many features with conventional TBI but possesses some unique aspects. In its mild form, it also shares many clinical features with PTSD but here again has distinct aspects. Although military medical providers depend on civilian standard of care guidelines when managing explosive blast mTBI, they are continually adapting their medical practice in order to optimize the treatment of this disease, particularly in a theater of war. It is clear that further rigorous scientific study of explosive blast mTBI at both the basic science and clinical levels is needed. This research must include improved understanding of the causes and mechanisms of explosive blast TBI as well as comprehensive epidemiologic studies to determine the prevalence of this disease and its risk factors. A widely accepted unambiguous clinical description of explosive blast mTBI with diagnostic criteria would greatly improve diagnosis. It is hoped that through appropriate research meaningful prevention, mitigation, and treatment strategies for explosive blast mTBI can be speedily realized. PMID:25702216

  7. Vehicle overturning vulnerability from air blast loads

    NASA Astrophysics Data System (ADS)

    Robinson, R. R.; Napadensky, H.; Longinow, A.

    1984-08-01

    The overturning response of an armored personnel carrier to air blast loads derived from a nuclear blast environment is presented. The orientation of the vehicle is side-on to the air blast shock front. It is assumed there is no translation at the downwind wheels, i.e., the roll over point. In addition, the vehicle is assumed to behave as a rigid body. That is, the suspension system are taken as rigid, so that the wheels and axles rotate in unison with the body. It can be shown that this assumption slightly overestimates the overturning resistance of vehicles with suspension systems. For a stiff suspension system, such as that of the APC, the rigid body behavior assumption is justified. The only motion possible for this analysis is rotation about the rollover point. The effect of overturning restraint systems has been included in the analysis by incorporating a perfectly plastic vehicle to ground connection on the upwind side of the vehicle. The results give the threshold nuclear environment that just causes overturning. The threshold environment is given in terms of a peak overpressure corresponding to a weapon yield. Results are presented for a range of weapon yields from 1KT to 1MT.

  8. Graphene tests of Klein phenomena

    E-print Network

    Stefano De Leo; Pietro Rotelli

    2012-02-07

    Graphene is characterized by chiral electronic excitations. As such it provides a perfect testing ground for the production of Klein pairs (electron/holes). If confirmed, the standard results for barrier phenomena must be reconsidered with, as a byproduct, the accumulation within the barrier of holes.

  9. Virtual Physics Laboratory: Wave Phenomena

    NSDL National Science Digital Library

    The Department of Physics and Astronomy

    This site from Northwestern University discusses wave phenomena. The site features interactive applets of various wave types, including longitudinal, transverse, mixed, and sound waves. Also included are animations of superposition, beat frequencies, and the distinction between phase and group velocities, wave packets, and wave reflections.

  10. Nuclear pairing: basic phenomena revisited

    E-print Network

    G. F. Bertsch

    2012-03-25

    I review the phenomena associated with pairing in nuclear physics, most prominently the ubiquitous presence of odd-even mass differences and the properties of the excitation spectra, very different for even-even and odd-A nuclei. There are also significant dynamical effects of pairing, visible in the inertias associated with nuclear rotation and large-amplitude shape deformation.

  11. Transport phenomena at metal surfaces

    Microsoft Academic Search

    L. A. Falkovsky

    1983-01-01

    Previous theoretical treatments of the scattering of conduction electrons at surfaces are reviewed and it is found that a more complete theory is necessary if the effects of surface scattering in transport phenomena are to be adequately understood. The boundary condition for the distribution function is derived and analysed in terms of the angle-dependent scattering probability. The skin effect, cyclotron

  12. Gravitational Anomaly and Transport Phenomena

    Microsoft Academic Search

    Karl Landsteiner; Eugenio Megías; Francisco Pena-Benitez

    2011-01-01

    Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity

  13. Visualizing Chemical Phenomena in Microdroplets

    ERIC Educational Resources Information Center

    Lee, Sunghee; Wiener, Joseph

    2011-01-01

    Phenomena that occur in microdroplets are described to the undergraduate chemistry community. Droplets having a diameter in the micrometer range can have unique and interesting properties, which arise because of their small size and, especially, their high surface area-to-volume ratio. Students are generally unfamiliar with the characteristics of…

  14. Seismo-acoustic analysis of the near quarry blasts using Plostina small aperture array

    NASA Astrophysics Data System (ADS)

    Ghica, Daniela; Stancu, Iulian; Ionescu, Constantin

    2013-04-01

    Seismic and acoustic signals are important to recognize different type of industrial blasting sources in order to discriminate between them and natural earthquakes. We have analyzed the seismic events listed in the Romanian catalogue (Romplus) for the time interval between 2011 and 2012, and occurred in the Dobrogea region, in order to determine detection seismo-acoustic signals of quarry blasts by Plostina array stations. Dobrogea is known as a seismic region characterized by crustal earthquakes with low magnitudes; at the same time, over 40 quarry mines are located in the area, being sources of blasts recorded both with the seismic and infrasound sensors of the Romanian Seismic Network. Plostina seismo-acoustic array, deployed in the central part of Romania, consists of 7 seismic sites (3C broad-band instruments and accelerometers) collocated with 7 infrasound instruments. The array is particularly used for the seismic monitoring of the local and regional events, as well as for the detection of infrasonic signals produced by various sources. Considering the characteristics of the infrasound sensors (frequency range, dynamic, sensibility), the array proved its efficiency in observing the signals produced by explosions, mine explosion and quarry blasts. The quarry mines included for this study cover distances of two hundreds of kilometers from the station and routinely generate explosions that are detected as seismic and infrasonic signals with Plostina array. The combined seismo-acoustic analysis uses two types of detectors for signal identification: one, applied for the seismic signal identification, is based on array processing techniques (beamforming and frequency-wave number analysis), while the other one, which is used for infrasound detection and characterization, is the automatic detector DFX-PMCC (Progressive Multi-Channel Correlation Method). Infrasonic waves generated by quarry blasts have frequencies ranging from 0.05 Hz up to at least 6 Hz and amplitudes below 5 Pa. Seismic data analysis shows that the frequency range of the signals are above 2 Hz. Surface explosions such as quarry blasts are useful sources for checking detection and location efficiency, when seismic measurements are added. The process is crucial for discrimination purposes and for establishing of a set of ground-truth infrasound events. Ground truth information plays a key role in the interpretation of infrasound signals, by including near-field observations from industrial blasts.

  15. A multiple gene complex on rice chromosome 4 is involved in durable resistance to rice blast.

    PubMed

    Fukuoka, S; Mizobuchi, R; Saka, N; Suprun, I; Ivan, S; Matsumoto, T; Okuno, K; Yano, M

    2012-08-01

    Quantitative trait loci (QTLs) for resistance to rice blast offer a potential source of durable disease resistance in rice. However, few QTLs have been validated in progeny testing, on account of their small phenotypic effects. To understand the genetic basis for QTL-mediated resistance to blast, we dissected a resistance QTL, qBR4-2, using advanced backcross progeny derived from a chromosome segment substitution line in which a 30- to 34-Mb region of chromosome 4 from the resistant cultivar Owarihatamochi was substituted into the genetic background of the highly susceptible Aichiasahi. The analysis resolved qBR4-2 into three loci, designated qBR4-2a, qBR4-2b, and qBR4-2c. The sequences of qBR4-2a and qBR4-2b, which lie 181 kb apart from each other and measure, 113 and 32 kb, respectively, appear to encode proteins with a putative nucleotide-binding site (NBS) and leucine-rich repeats (LRRs). Sequence analysis of the donor allele of qBR4-2a, the region with the largest effect among the three, revealed sequence variations in the NBS-LRR region. The effect of qBR4-2c was smallest among the three, but its combination with the donor alleles of qBR4-2a and qBR4-2b significantly enhanced blast resistance. qBR4-2 comprises three tightly linked QTLs that control blast resistance in a complex manner, and thus gene pyramiding or haplotype selection is the recommended strategy for improving QTL-mediated resistance to blast disease through the use of this chromosomal region. PMID:22446930

  16. Ubiquitin Carboxy-Terminal Hydrolase-L1 as a Serum Neurotrauma Biomarker for Exposure to Occupational Low-Level Blast

    PubMed Central

    Carr, Walter; Yarnell, Angela M.; Ong, Ricardo; Walilko, Timothy; Kamimori, Gary H.; da Silva, Uade; McCarron, Richard M.; LoPresti, Matthew L.

    2015-01-01

    Repeated exposure to low-level blast is a characteristic of a few select occupations and there is concern that such occupational exposures present risk for traumatic brain injury. These occupations include specialized military and law enforcement units that employ controlled detonation of explosive charges for the purpose of tactical entry into secured structures. The concern for negative effects from blast exposure is based on rates of operator self-reported headache, sleep disturbance, working memory impairment, and other concussion-like symptoms. A challenge in research on this topic has been the need for improved assessment tools to empirically evaluate the risk associated with repeated exposure to blast overpressure levels commonly considered to be too low in magnitude to cause acute injury. Evaluation of serum-based neurotrauma biomarkers provides an objective measure that is logistically feasible for use in field training environments. Among candidate biomarkers, ubiquitin carboxy-terminal hydrolase-L1 (UCH-L1) has some empirical support and was evaluated in this study. We used daily blood draws to examine acute change in UCH-L1 among 108 healthy military personnel who were exposed to repeated low-level blast across a 2-week period. These research volunteers also wore pressure sensors to record blast exposures, wrist actigraphs to monitor sleep patterns, and completed daily behavioral assessments of symptomology, postural stability, and neurocognitive function. UCH-L1 levels were elevated as a function of participating in the 2-week training with explosives, but the correlation of UCH-L1 elevation and blast magnitude was weak and inconsistent. Also, UCH-L1 elevations did not correlate with deficits in behavioral measures. These results provide some support for including UCH-L1 as a measure of central nervous system effects from exposure to low-level blast. However, the weak relation observed suggests that additional indicators of blast effect are needed.

  17. Sensitivity of blackbody reference panels to wind blast

    NASA Technical Reports Server (NTRS)

    Hoover, Gordon

    1992-01-01

    As part of the effort at Stennis and JPL to discover the root causes of Thermal Infrared Multispectral Scanner's (TIMS') temperature calibration errors, a series of experiments were performed to measure the sensitivity of a heated plate to cooling by wind blast. A powerful blower which was capable of generating a jet of wind in excess of 200 miles per hour was set up. In the jet, an electrically heated copper plate, one quarter of an inch thick and six inches square, was mounted. The electrical heaters were capable of delivering a total power of 800 watts. The power to the heaters was feedback controlled with reference to a thermistor mounted on the back of the copper plate. The plate was mounted about 2.5 feet from the blower nozzle, at about 45 deg to the direction of the jet. The jet was wide enough to wash the whole surface and its temperature at the plate was about 28 C.

  18. A multisite study of the relationships between blast exposures and symptom reporting in a post-deployment active duty military population with mild traumatic brain injury.

    PubMed

    Reid, Matthew W; Miller, Kelly J; Lange, Rael T; Cooper, Douglas B; Tate, David F; Bailie, Jason; Brickell, Tracey A; French, Louis M; Asmussen, Sarah; Kennedy, Jan E

    2014-12-01

    Explosive devices have been the most frequent cause of traumatic brain injury (TBI) among deployed contemporary U.S. service members. The purpose of this study was to examine the influence of previous cumulative blast exposures (that did or did not result in TBI) on later post-concussion and post-traumatic symptom reporting after sustaining a mild TBI (MTBI). Participants were 573 service members who sustained MTBI divided into four groups by number of blast exposures (1, 2, 3, and 4-10) and a nonblast control group. Post-concussion symptoms were measured using the Neurobehavioral Symptom Inventory (NSI) and post-traumatic stress disorder (PTSD) symptoms using the Post-traumatic Checklist-Civilian version (PCL-C). Results show groups significantly differed on total NSI scores (p<0.001), where symptom endorsement increased as number of reported blast exposures increased. Total NSI scores were significantly higher for the 3- and 4-10 blast groups compared with the 1- and 2-blast groups with effect sizes ranging from small to moderate (d=0.31 to 0.63). After controlling for PTSD symptoms using the PCL-C total score, NSI total score differences remained between the 4-10-blast group and the 1- and 2-blast groups, but were less pronounced (d=0.35 and d=0.24, respectively). Analyses of NSI subscale scores using PCL-C scores as a covariate revealed significant between-blast group differences on cognitive, sensory, and somatic, but not affective symptoms. Regression analyses revealed that cumulative blast exposures accounted for a small but significant amount of the variance in total NSI scores (4.8%; p=0.009) and total PCL-C scores (2.3%; p<0.001). Among service members exposed to blast, post-concussion symptom reporting increased as a function of cumulative blast exposures. Future research will need to determine the relationship between cumulative blast exposures, symptom reporting, and neuropathological changes. PMID:25036531

  19. A Novel Approach for Blast-Induced Flyrock Prediction Based on Imperialist Competitive Algorithm and Artificial Neural Network

    PubMed Central

    Marto, Aminaton; Jahed Armaghani, Danial; Tonnizam Mohamad, Edy; Makhtar, Ahmad Mahir

    2014-01-01

    Flyrock is one of the major disturbances induced by blasting which may cause severe damage to nearby structures. This phenomenon has to be precisely predicted and subsequently controlled through the changing in the blast design to minimize potential risk of blasting. The scope of this study is to predict flyrock induced by blasting through a novel approach based on the combination of imperialist competitive algorithm (ICA) and artificial neural network (ANN). For this purpose, the parameters of 113 blasting operations were accurately recorded and flyrock distances were measured for each operation. By applying the sensitivity analysis, maximum charge per delay and powder factor were determined as the most influential parameters on flyrock. In the light of this analysis, two new empirical predictors were developed to predict flyrock distance. For a comparison purpose, a predeveloped backpropagation (BP) ANN was developed and the results were compared with those of the proposed ICA-ANN model and empirical predictors. The results clearly showed the superiority of the proposed ICA-ANN model in comparison with the proposed BP-ANN model and empirical approaches. PMID:25147856

  20. Preparation of Aluminum Coatings by Atmospheric Plasma Spraying and Dry-Ice Blasting and Their Corrosion Behavior

    NASA Astrophysics Data System (ADS)

    Dong, Shu-Juan; Song, Bo; Zhou, Gen-Shu; Li, Chang-Jiu; Hansz, Bernard; Liao, Han-Lin; Coddet, Christian

    2013-10-01

    Aluminum coating, as an example of spray coating material with low hardness, was deposited by atmospheric plasma spraying while dry-ice blasting was applied during the deposition process. The deposited coatings were characterized in terms of microstructure, porosity, phase composition, and the valence states. The results show that the APS aluminum coatings with dry-ice blasting present a porosity of 0.35 ± 0.02%, which is comparable to the bulk material formed by the mechanical compaction. In addition, no evident oxide has been detected, except for the very thin and impervious oxide layer at the outermost layer. Compared to plasma-sprayed Al coatings without dry-ice blasting, the adhesion increased by 52% for Al substrate using dry-ice blasting, while 25% for steel substrate. Corrosion behavior of coated samples was evaluated in 3.5 wt.% NaCl aqueous using electrochemistry measurements. The electrochemical results indicated that APS Al coating with dry-ice blasting was more resistant to pitting corrosion than the conventional plasma-sprayed Al coating.

  1. BLAST OBSERVATIONS OF RESOLVED GALAXIES: TEMPERATURE PROFILES AND THE EFFECT OF ACTIVE GALACTIC NUCLEI ON FIR TO SUBMILLIMETER EMISSION

    SciTech Connect

    Wiebe, Donald V.; Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Ade, Peter A. R.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip; Pascale, Enzo [School of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff, CF24 3AA (United Kingdom); Bock, James J. [Jet Propulsion Laboratory, Pasadena, CA 91109-8099 (United States); Devlin, Mark J.; Dicker, Simon; Klein, Jeff; Rex, Marie [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Gundersen, Joshua O. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Hughes, David H. [Instituto Nacional de AstrofIsica Optica y Electronica, Aptdo. Postal 51 y 216, 72000 Puebla (Mexico); Martin, Peter G. [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Netterfield, Calvin B. [Department of Physics, University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7 (Canada); Olmi, Luca [Istituto di Radioastronomia, Largo E. Fermi 5, I-50125, Firenze (Italy); Patanchon, Guillaume [Laboratoire APC, 10, rue Alice Domon et Leonie Duquet 75205 Paris (France)

    2009-12-20

    Over the course of two flights, the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) made resolved maps of seven nearby (<25 Mpc) galaxies at 250, 350, and 500 mum. During its 2005 June flight from Sweden, BLAST observed a single nearby galaxy, NGC 4565. During the 2006 December flight from Antarctica, BLAST observed the nearby galaxies NGC 1097, NGC 1291, NGC 1365, NGC 1512, NGC 1566, and NGC 1808. We fit physical dust models to a combination of BLAST observations and other available data for the galaxies observed by Spitzer. We fit a modified blackbody to the remaining galaxies to obtain total dust mass and mean dust temperature. For the four galaxies with Spitzer data, we also produce maps and radial profiles of dust column density and temperature. We measure the fraction of BLAST detected flux originating from the central cores of these galaxies and use this to calculate a 'core fraction', an upper limit on the 'active galactic nucleus fraction' of these galaxies. We also find our resolved observations of these galaxies give a dust mass estimate 5-19 times larger than an unresolved observation would predict. Finally, we are able to use these data to derive a value for the dust mass absorption coefficient of kappa = 0.29 +- 0.03 m{sup 2} kg{sup -1} at 250 mum. This study is an introduction to future higher-resolution and higher-sensitivity studies to be conducted by Herschel and SCUBA-2.

  2. A novel approach for blast-induced flyrock prediction based on imperialist competitive algorithm and artificial neural network.

    PubMed

    Marto, Aminaton; Hajihassani, Mohsen; Armaghani, Danial Jahed; Mohamad, Edy Tonnizam; Makhtar, Ahmad Mahir

    2014-01-01

    Flyrock is one of the major disturbances induced by blasting which may cause severe damage to nearby structures. This phenomenon has to be precisely predicted and subsequently controlled through the changing in the blast design to minimize potential risk of blasting. The scope of this study is to predict flyrock induced by blasting through a novel approach based on the combination of imperialist competitive algorithm (ICA) and artificial neural network (ANN). For this purpose, the parameters of 113 blasting operations were accurately recorded and flyrock distances were measured for each operation. By applying the sensitivity analysis, maximum charge per delay and powder factor were determined as the most influential parameters on flyrock. In the light of this analysis, two new empirical predictors were developed to predict flyrock distance. For a comparison purpose, a predeveloped backpropagation (BP) ANN was developed and the results were compared with those of the proposed ICA-ANN model and empirical predictors. The results clearly showed the superiority of the proposed ICA-ANN model in comparison with the proposed BP-ANN model and empirical approaches. PMID:25147856

  3. Development of Rock Engineering Systems-Based Models for Flyrock Risk Analysis and Prediction of Flyrock Distance in Surface Blasting

    NASA Astrophysics Data System (ADS)

    Faramarzi, Farhad; Mansouri, Hamid; Farsangi, Mohammad Ali Ebrahimi

    2014-07-01

    The environmental effects of blasting must be controlled in order to comply with regulatory limits. Because of safety concerns and risk of damage to infrastructures, equipment, and property, and also having a good fragmentation, flyrock control is crucial in blasting operations. If measures to decrease flyrock are taken, then the flyrock distance would be limited, and, in return, the risk of damage can be reduced or eliminated. This paper deals with modeling the level of risk associated with flyrock and, also, flyrock distance prediction based on the rock engineering systems (RES) methodology. In the proposed models, 13 effective parameters on flyrock due to blasting are considered as inputs, and the flyrock distance and associated level of risks as outputs. In selecting input data, the simplicity of measuring input data was taken into account as well. The data for 47 blasts, carried out at the Sungun copper mine, western Iran, were used to predict the level of risk and flyrock distance corresponding to each blast. The obtained results showed that, for the 47 blasts carried out at the Sungun copper mine, the level of estimated risks are mostly in accordance with the measured flyrock distances. Furthermore, a comparison was made between the results of the flyrock distance predictive RES-based model, the multivariate regression analysis model (MVRM), and, also, the dimensional analysis model. For the RES-based model, R 2 and root mean square error (RMSE) are equal to 0.86 and 10.01, respectively, whereas for the MVRM and dimensional analysis, R 2 and RMSE are equal to (0.84 and 12.20) and (0.76 and 13.75), respectively. These achievements confirm the better performance of the RES-based model over the other proposed models.

  4. Repeat Observations of New Impact Sites on Mars: Changes in Blast Zones

    NASA Astrophysics Data System (ADS)

    Daubar, I.; Geissler, P. E.; McEwen, A. S.; Dundas, C. M.; Byrne, S.

    2012-12-01

    New, dated craters on Mars (Malin et al. 2006, Daubar et al. 2012) are the freshest available examples of impact processes, and some of the only recently-modified surfaces with known ages for the initial surface disturbance. HiRISE has monitored many of these sites over three Mars years. The rates and characteristics of changes at these sites help us understand the initial impact processes and the modification processes that have occurred since. Future applications might include constraining ages of similar impacts that cannot be definitively dated by previous images and measuring variations in the rate of fading over time, perhaps even seasonal variations that would be important for dating dark marks that are only a few Mars years old. New impacts have an extended "blast zone" of (usually) lower albedo surrounding the craters. Blast zones are created by removal of high-albedo surface dust by various atmosphere/surface interactions of the shock waves associated with the descent and impact of the impactor and ejecta (Malin et al. 2006). Their creation could also (in addition?) be related to shock effects on small-scale surface texture. Features vary by site and include diffuse dark halos, dark arcuate or radial rays, light and dark-toned ejecta, slope streaks, and complex combinations thereof. Geissler et al. (2010a) reported that out of 14 sites with repeat imaging, only one site showed significant changes thus far. With 245 known impacts and many more repeat images, we can now extend this study to sites with different ages, target materials, and types of blast features. Surprisingly, some sites still show no detectable changes after three martian years, even after the 2007 global dust storm. In comparison, rover tracks fade on timescales of one martian year (Geissler et al. 2010b). Many other sites show changes, most commonly fading of the blast zone. Fading is most likely due to airfall of dust bringing the blast zones back to the ambient surrounding albedo. In some cases, however, originally dark blast zones have lightened over time, even becoming brighter than their surroundings. This phenomenon is unexplained; it may have causes in common with brightening slope streaks. Previous explanations for brightening slope streaks include topographic lighting effects and removal of surface roughness (Beyer et al. 2008). The first explanation would not apply in cases where repeat images have very similar lighting and view angles. For either explanation to apply, the blast zones must have some topography below HiRISE's resolution. Alternatively, material may have been exposed that is reacting differently to the weathering processes that cause other blast zones to fade. For example, where subsurface ice is exposed (Byrne et al. 2009), perhaps bright salts are ejected and left behind as a sublimation lag. This doesn't explain brightening of blast zones at lower latitudes, though. There's no reason to think that aeolian deposition of bright dust would occur preferentially within blast zones, but aeolian erosion might be more effective on recently-disturbed surfaces.

  5. Computational Hydrocode Study of Target Damage due to Fragment-Blast Impact

    SciTech Connect

    Hatch-Aguilar, T; Najjar, F; Szymanski, E

    2011-03-24

    A target's terminal ballistic effects involving explosively generated fragments, along with the original blast, are of critical importance for many different security and safety related applications. Personnel safety and protective building design are but a few of the practical disciplines that can gain from improved understanding combined loading effects. Traditionally, any engineering level analysis or design effort involving explosions would divide the target damage analysis into two correspondingly critical areas: blast wave and fragment related impact effects. The hypothesis of this paper lies in the supposition that a linear combination of a blast-fragment loading, coupled with an accurate target response description, can lead to a non-linear target damage effect. This non-linear target response could then stand as the basis of defining what a synergistic or combined frag-blast loading might actually look like. The table below, taken from Walters, et. al. categorizes some of the critical parameters driving any combined target damage effect and drives the evaluation of results. Based on table 1 it becomes clear that any combined frag-blast analysis would need to account for the target response matching similar ranges for the mechanics described above. Of interest are the critical times upon which a blast event or fragment impact loading occurs relative to the target's modal response. A blast, for the purposes of this paper is defined as the sudden release of chemical energy from a given material (henceforth referred to as an energetic material) onto its surrounding medium. During the coupling mechanism a discrete or discontinuous shockwave is generated. This shockwave travels outward from the source transferring energy and momentum to any surrounding objects including personnel and engineering structures. From an engineering perspective blast effects are typically characterized by way of physical characteristics such as Peak Pressure (PP), Time of Arrival (TOA), Pressure-Impulse (PI) and Time of Duration (TD). Other peculiarities include the radial decrease in pressure from the source, any fireball size measurement, and subsequent increase in temperature from the passing of the shockwave through the surrounding medium. In light of all of these metrics, the loading any object receives from a blast event becomes intricately connected to the distance between itself and the source. Because of this, a clear distinction is made between close-in effects and those from a source far away from the object of interest. Explosively generated fragments on the other hand are characterized by means of their localized damage potential. Metrics such as whether the fragment penetrates or perforates a given object is quantified as well as other variables including fragment's residual velocity, % kinetic energy decrease, residual fragment mass and other exit criteria. A fragment launched under such violent conditions could easily be traveling at speeds in excess of 2500 ft/s. Given these speeds it is conceivable to imagine how any given fragment could deliver a concentrated load to a target and penetrates through walls, vehicles or even the protection systems of nearby personnel. This study will focus on the individual fragment-target impact event with the hopes of expanding it to eventually include statistical procedures. Since this is a modeling excursion into the combined frag-blast target damage effects the numerical methods used to frame this problem become important in-so-far as the simulations are done in a consistent manner. For this study a Finite-Element based Hydrocode solution called ALE3D (ALE=Arbitrary Lagrangian-Eulerian) was utilized. ALE3D is developed by Lawrence Livermore National Laboratory (Livermore, CA), and as this paper will show, successfully implemented a converged ALE formulation including as many of the different aspects needed to query the synergistic damage on a given target. Further information on the modeling setup is included.

  6. Blast mines: physics, injury mechanisms and vehicle protection.

    PubMed

    Ramasamy, A; Hill, A M; Hepper, A E; Bull, A M J; Clasper, J C

    2009-12-01

    Since World War II, more vehicles have been lost to land mines than all other threats combined. Anti-vehicular (AV) mines are capable of disabling a heavy vehicle, or completely destroying a lighter vehicle. The most common form of AV mine is the blast mine, which uses a large amount of explosive to directly damage the target. In a conventional military setting, landmines are used as a defensive force-multiplier and to restrict the movements of the opposing force. They are relatively cheap to purchase and easy to acquire, hence landmines are also potent weapons in the insurgents' armamentarium. The stand-offnature of its design has allowed insurgents to cause significant injuries to security forces in current conflicts with little personal risk. As a result, AV mines and improvised explosive devices (IEDs) have become the most common cause of death and injury to Coalition and local security forces operating in Iraq and Afghanistan. Detonation of an AV mine causes an explosive, exothermic reaction which results in the formation of a shockwave followed by a rapid expansion of gases. The shockwave is mainly reflected by the soillair interface and fractures the soil cap overthe mine. The detonation products then vent through the voids in the soil, resulting in a hollow inverse cone which consists of the detonation gases surrounded by the soil ejecta. It is the combination of the detonation products and soil ejecta that interact with the target vehicle and cause injury to the vehicle occupants. A number of different strategies are required to mitigate the blast effects of an explosion. Primary blast effects can be reduced by increasing the standoff distance between the seat of the explosion and the crew compartment. Enhancement of armour on the base of the vehicle, as well as improvements in personal protection can prevent penetration of fragments. Mitigating tertiary effects can be achieved by altering the vehicle geometry and structure, increasing vehicle mass, as well as developing new strategies to reduce the transfer of the impulse through the vehicle to the occupants. Protection from thermal injury can be provided by incorporating fire resistant materials into the vehicle and in personal clothing. The challenge for the vehicle designer is the incorporation of these protective measures within an operationally effective platform. PMID:20397600

  7. Undergraduates Understanding of Cardiovascular Phenomena

    NSDL National Science Digital Library

    PhD Joel A. Michael (Rush Medical College Department of Molecular Biophysics and Physiology)

    2002-06-01

    Undergraduates students in 12 courses at 8 different institutions were surveyed to determine the prevalence of 13 different misconceptions (conceptual difficulties) about cardiovascular function. The prevalence of these misconceptions ranged from 20 to 81% and, for each misconception, was consistent across the different student populations. We also obtained explanations for the studentsÂ? answers either as free responses or with follow-up multiple-choice questions. These results suggest that students have a number of underlying conceptual difficulties about cardiovascular phenomena. One possible source of some misconceptions is the studentsÂ? inability to apply simple general models to specific cardiovascular phenomena. Some implications of these results for teachers of physiology are discussed.

  8. Emergent Phenomena via Molecular Dynamics

    NASA Astrophysics Data System (ADS)

    Rapaport, D. C.

    Emergent phenomena are unusual because they are not obvious consequences of the design of the systems in which they appear, a feature no less relevant when they are being simulated. Several systems that exhibit surprisingly rich emergent behavior, each studied by molecular dynamics (MD) simulation, are described: (i) Modeling self-assembly processes associated with virus growth reveals the ability to achieve error-free assembly, where paradoxically, near-maximum yields are due to reversible bond formation. (ii) In fluids studied at the atomistic level, complex hydrodynamic phenomena in rotating and convecting fluids - the Taylor- Couette and Rayleigh-Bénard instabilities - can be reproduced, despite the limited length and time scales accessible by MD. (iii) Segregation studies of granular mixtures in a rotating drum reproduce the expected, but counterintuitive, axial and radial segregation, while for the case of a vertically vibrated layer a novel form of horizontal segregation is revealed.

  9. 15Year blast furnace campaign concept for the reline of blast furnace C at Iscor

    Microsoft Academic Search

    Noska; T. G. L

    1995-01-01

    Since the 1970`s, when blast furnace campaigns of 3 to 5 years were experienced at the Vanderbijlpark Works, consequent improvements of cooling and refractory concepts as well as the development of a hot guniting practice for belly and lower shaft resulted in campaigns of 10 years and more. Having mastered the problems in belly and lower shaft, the furnace hearth

  10. Blasted’s Hysteria: Rape, Realism, and the Thresholds of the Visible

    Microsoft Academic Search

    Kim Solga

    2007-01-01

    A curious blind spot remains in the critical response to Sarah Kane’s Blasted : the rape of Cate by Ian. In a play famous for its onstage violence, why is this rape, one of its pivotal moments of brutality, left unstaged? My article seeks to worry this lacuna by exploring the theoretical and historical dimensions of the ‘‘missing’’ in Kane’s

  11. New phenomena searches at CDF

    SciTech Connect

    Soha, Aron; /UC, Davis

    2006-04-01

    The authors report on recent results from the Collider Detector at Fermilab (CDF) experiment, which is accumulating data from proton-antiproton collisions with {radical}s = 1.96 TeV at Run II of the Fermilab Tevatron. The new phenomena being explored include Higgs, Supersymmetry, and large extra dimensions. They also present the latest results of searches for heavy objects, which would indicate physics beyond the Standard Model.

  12. Visualization of solidification front phenomena

    NASA Technical Reports Server (NTRS)

    Workman, Gary L.; Smith, Guy A.

    1993-01-01

    Directional solidification experiments have been utilized throughout the Materials Processing in Space Program to provide an experimental platform which minimizes variables in solidification experiments. Because of the wide-spread use of this experimental technique in space-based research, it has become apparent that a better understanding of all the phenomena occurring during solidification can be better understood if direct visualization of the solidification interface were possible.

  13. Mathematical Modeling of Diverse Phenomena

    NASA Technical Reports Server (NTRS)

    Howard, J. C.

    1979-01-01

    Tensor calculus is applied to the formulation of mathematical models of diverse phenomena. Aeronautics, fluid dynamics, and cosmology are among the areas of application. The feasibility of combining tensor methods and computer capability to formulate problems is demonstrated. The techniques described are an attempt to simplify the formulation of mathematical models by reducing the modeling process to a series of routine operations, which can be performed either manually or by computer.

  14. VIEW FROM THE SOUTH OF THE #2 BLAST FURNACE AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM THE SOUTH OF THE #2 BLAST FURNACE AND CASTING SEED ON THE LEFT, THE #1 BLAST FURNACE AND CASTING SHED ON THE RIGHT, AND THE STOVES, BOILERS, AND AUXILIARY EQUIPMENT IN THE CENTER. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  15. VIEW OF THE #2 BLAST FURNACE FROM THE EAST, SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF THE #2 BLAST FURNACE FROM THE EAST, SHOWING SKIP HOIST, DUST CATCHER AND STOCK BINS IN THE FOREGROUND. #2 CASTING SHED IS TO THE LEFT, HOT BLAST MAIN IS ON THE RIGHT. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  16. 1. View of blast deflector fences along southwest side of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View of blast deflector fences along southwest side of the operational apron. View to west. - Offutt Air Force Base, Looking Glass Airborne Command Post, Blast Deflector Fences, Northeast & Southwest sides of Operational Apron, Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  17. 2. View of blast deflector fences along northeast side of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. View of blast deflector fences along northeast side of the operational apron. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Blast Deflector Fences, Northeast & Southwest sides of Operational Apron, Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  18. STUDY OF BLAST WAVE IMPACT ON CONCRETE AJIT GEEVARGHESE JOHN

    E-print Network

    Texas at Arlington, University of

    STUDY OF BLAST WAVE IMPACT ON CONCRETE by AJIT GEEVARGHESE JOHN Presented to the Faculty on numerous occasions to run my experiments. I would also express my gratitude to Kenneth without whom I would OF BLAST WAVE IMPACT ON CONCRETE Publication No. ______ Ajit Geevarghese John, M.S. The University of Texas

  19. Blast-related traumatic brain injury research gaps”

    Microsoft Academic Search

    M. J. Leggieri

    2009-01-01

    The DoD Blast Injury Research Program was established at the direction of Congress in the FY 2006 National Defense Authorization Act to coordinate and manage the medical research efforts and programs of the DoD relating to the prevention, mitigation, and treatment of blast injuries. The Secretary of Defense has designated the Secretary of the Army as the Executive Agent (EA)

  20. Storage stability of flour-blasted brown rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brown rice was blasted with rice flour rather than sand in a sand blaster to make microscopic nicks and cuts so that water can easily penetrate into the brown rice endosperm and cook the rice in a shorter time. The flour-blasted American Basmati brown rice, long grain brown rice, and parboiled long...

  1. Computational studies of polyurea coated steel plate under blast loads

    E-print Network

    · High Abrasion resistance Source: PCI, http://www.pcimag.com/CDA/Archives/779f754db76a7010VgnVCM100000f Research (ONR N00014-05-1-0844) #12;Background · Lightweight material is sought for blast resistant coatings increase blast resistance of existing and temporary structures, Porter et al., AFRL #12;Motives

  2. Note: A table-top blast driven shock tube

    NASA Astrophysics Data System (ADS)

    Courtney, Michael W.; Courtney, Amy C.

    2010-12-01

    The prevalence of blast-induced traumatic brain injury in conflicts in Iraq and Afghanistan has motivated laboratory scale experiments on biomedical effects of blast waves and studies of blast wave transmission properties of various materials in hopes of improving armor design to mitigate these injuries. This paper describes the design and performance of a table-top shock tube that is more convenient and widely accessible than traditional compression driven and blast driven shock tubes. The design is simple: it is an explosive driven shock tube employing a rifle primer that explodes when impacted by the firing pin. The firearm barrel acts as the shock tube, and the shock wave emerges from the muzzle. The small size of this shock tube can facilitate localized application of a blast wave to a subject, tissue, or material under test.

  3. BLAST: RESOLVING THE COSMIC SUBMILLIMETER BACKGROUND

    SciTech Connect

    Marsden, Gaelen; Chapin, Edward L.; Halpern, Mark; Ngo, Henry [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Ade, Peter A. R.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip; Moncelsi, Lorenzo; Pascale, Enzo [School of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff, CF24 3AA (United Kingdom); Bock, James J. [Jet Propulsion Laboratory, Pasadena, CA 91109-8099 (United States); Devlin, Mark J.; Dicker, Simon R.; Klein, Jeff [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Gundersen, Joshua O. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Hughes, David H. [Instituto Nacional de AstrofIsica Optica y Electronica (INAOE), Aptdo. Postal 51 y 72000 Puebla (Mexico); Magnelli, Benjamin [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, IRFU/Service d'Astrophysique, Bat. 709, CEA-Saclay, F-91191 gif-sur-Yvette Cedex (France); Netterfield, Calvin B. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Olmi, Luca [Physics Department, University of Puerto Rico, Rio Piedras Campus, Box 23343, UPR station, Puerto Rico 00931 (United States); Patanchon, Guillaume, E-mail: gmarsden@phas.ubc.c [Universite Paris Diderot, Laboratoire APC, 10, rue Alice Domon et Leonie Duquet 75205 Paris (France)

    2009-12-20

    The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) has made 1 deg{sup 2}, deep, confusion-limited maps at three different bands, centered on the Great Observatories Origins Deep Survey South Field. By calculating the covariance of these maps with catalogs of 24 mum sources from the Far-Infrared Deep Extragalactic Legacy Survey, we have determined that the total submillimeter intensities are 8.60 +- 0.59, 4.93 +- 0.34, and 2.27 +- 0.20 nW m{sup -2} sr{sup -1} at 250, 350, and 500 mum, respectively. These numbers are more precise than previous estimates of the cosmic infrared background (CIB) and are consistent with 24 mum-selected galaxies generating the full intensity of the CIB. We find that the fraction of the CIB that originates from sources at z >= 1.2 increases with wavelength, with 60% from high-redshift sources at 500 mum. At all BLAST wavelengths, the relative intensity of high-z sources is higher for 24 mum-faint sources than that for 24 mum-bright sources. Galaxies identified as active galactic nuclei (AGNs) by their Infrared Array Camera colors are 1.6-2.6 times brighter than the average population at 250-500 mum, consistent with what is found for X-ray-selected AGNs. BzK-selected galaxies are found to be moderately brighter than typical 24 mum-selected galaxies in the BLAST bands. These data provide high-precision constraints for models of the evolution of the number density and intensity of star-forming galaxies at high redshift.

  4. Oklahoma blast forces unsettling design questions

    SciTech Connect

    NONE

    1995-05-01

    The bomb that brought down a government building in Oklahoma City killed hundreds of people after it was detonated near the building`s key supports. The blast has reopened a long-simmering debate on safety by design. Structurally, it`s not practical to designing bomb-proof buildings. But it is possible to engineer a structure to deform rather than go through immediate progressive collapse. Delaying collapse gives occupants extra time to evacuate. And that could mean the difference between life and death. The construction material of choice really {open_quotes}depends on the height of the building and the lateral load resisting system,{close_quotes} says Charles H. Thornton of Thornton-Tomasetti/Engineers, New York City. But whether in steel or reinforced concrete, moment-resisting frames, which are inherently redundant, give horizontal components the ability to take reversals of stress common in explosions, he says. Simple frames do not. {open_quotes}They go down like a house of cards,{close_quotes} says Thornton. In reinforced concrete moment frames, beam reinforcing steel is continuous. In simple reinforced concrete frames, beam rebar only penetrates the column for a determined number of inches based on the length of the span. And it is absent from the mid-span of the beam. In a blast from below, the beam, its top usually in compression and bottom in tension, deflects up, throwing the beam top into tension. With no rebar, it loses structural integrity, and falls apart. With rebar, it has a chance of surviving. If a building is not designed for blasts, a steel frame might be better under a reasonably small bomb because steel has equal capacity in tension and compression, and concrete has capacity only in compression, says Thornton.

  5. Steel Foil Improves Performance Of Blasting Caps

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.; Perry, Ronnie; Schimmel, Morry L.

    1990-01-01

    Blasting caps, which commonly include deep-drawn aluminum cups, give significantly higher initiation performance by application of steel foils on output faces. Steel closures 0.005 in. (0.13 mm) thick more effective than aluminum. Caps with directly bonded steel foil produce fragment velocities of 9,300 ft/s (2.8 km/s) with large craters and unpredictable patterns to such degree that no attempts made to initiate explosions. Useful in military and aerospace applications and in specialized industries as mining and exploration for oil.

  6. NASA TEERM Project: Corn Based Blast Media

    NASA Technical Reports Server (NTRS)

    Griffin, Chuck

    2009-01-01

    Coatings removal is a necessary part of the maintenance, repair, and overhaul activities at many NASA centers and contractor support sites. Sensitive substrates, such as composites and thin aluminum alloys require special handling such as the use of chemical stripping, pneumatic hand sanding, or softer blast media. Type V, acrylic based PMB is commonly used to de-coat, strip, or de-paint the delicate substrates of the Solid Rocket Boosters (SRBs) currently used in support of the Shuttle and slated to be used in support of CxP.

  7. Blast energy mitigation in porous rocks

    NASA Astrophysics Data System (ADS)

    Essink, Brittany C.

    Geo-materials are commonly used and sought after for blast mitigation applications due to their wide availability and low cost compared to industry trademarked materials. Characterization of these natural geo-materials such as volcanic rocks is of paramount importance in determining their blast mitigation capabilities. While there is a large amount of information available for materials such as concrete or sand blasts, information on the properties of volcanic rocks is far more scarce. This lack of data is due to the wide range of existing natural volcanic rocks and the variation in the minerals and pore structures of the rocks. In this thesis, silicate volcanic rock samples are characterized both through static and dynamic experimental methods. Initial X-ray powder diffraction scans have been conducted and analyzed to obtain the mineral composition information of the rock samples. Additional tomographic scans under quasi-static loading have been recorded to better understand the internal composition of the material pore structure and the material fracture. For this study, standard compression experiments were conducted at two separate strain rates for ten samples each on a UTM test frame to characterize the behavior of the rock under quasi-static conditions. High strain rate uniaxial compression tests were conducted for three strain rates using a split-Hopkinson pressure bar with pulse shaping to determine the dynamic response of the material. The stress-strain data from the experiments was used to determine the modulus of toughness of the material. Due to the high porosity and heterogeneity of the material, 25 samples were used for dynamic experimentation to attempt to capture and minimize the effects of scatter in the natural material. High speed photography was used to capture the sample deformation during two separate strain rates and to visualize crack propagation and strain rate in the samples. It was found that after an initial yielding, the material is able to withstand a sustained loading which is desirable for materials used in blast loading applications. Another desirable trait that was observed in this material is that higher strain rates provide a higher sustained stress value. Further dynamic experiments on the rock with larger strains are necessary to completely compare the energy absorption capabilities of the material at high strain rates.

  8. Non-equilibrium ionized blast wave

    NASA Technical Reports Server (NTRS)

    Wu, S. T.

    1974-01-01

    The structure of a cylindrical blast wave with ionization at non-LTE conditions was calculated using equations previously developed by Wu and Fu (1970). The degree of ionization was predicted by a modified Saha equation. Temperature profiles show that the temperature at non-LTE conditions is lower than at LTE near the shock front. This corresponds to a higher degree of ionization for the non-LTE limit, which indicates that the neutral gas absorption is much more efficient at non-LTE than at the LTE limit. The decaying velocity under non-LTE is approximately 15% less than under LTE.

  9. Improved CFD Model to Predict Flow and Temperature Distributions in a Blast Furnace Hearth

    NASA Astrophysics Data System (ADS)

    Komiyama, Keisuke M.; Guo, Bao-Yu; Zughbi, Habib; Zulli, Paul; Yu, Ai-Bing

    2014-10-01

    The campaign life of a blast furnace is limited by the erosion of hearth refractories. Flow and temperature distributions of the liquid iron have a significant influence on the erosion mechanism. In this work, an improved three-dimensional computational fluid dynamics model is developed to simulate the flow and heat transfer phenomena in the hearth of BlueScope's Port Kembla No. 5 Blast Furnace. Model improvements feature more justified input parameters in turbulence modeling, buoyancy modeling, wall boundary conditions, material properties, and modeling of the solidification of iron. The model is validated by comparing the calculated temperatures with the thermocouple data available, where agreements are established within ±3 pct. The flow distribution in the hearth is discussed for intact and eroded hearth profiles, for sitting and floating coke bed states. It is shown that natural convection affects the flow in several ways: for example, the formation of (a) stagnant zones preventing hearth bottom from eroding or (b) the downward jetting of molten liquid promoting side wall erosion, or (c) at times, a vortex-like peripheral flow, promoting the "elephant foot" type erosion. A significant influence of coke bed permeability on the macroscopic flow pattern and the refractory temperature is observed.

  10. Numerical analysis of blast-induced wave propagation using FSI and ALEmulti-material formulations

    Microsoft Academic Search

    Mehdi Sotudeh Chafi; Ghodrat Karami; Mariusz Ziejewski

    2009-01-01

    As explosive blasts continue to cause casualties in both civil and military environments, there is a need to identify the dynamic interaction of blast loading with structures, to know the shock mitigating mechanisms and, most importantly, to identify the mechanisms of blast trauma. This paper examines the air-blast simulation using Arbitrary Lagrangian Eulerian (ALE) multi-material formulation. It will explain how

  11. Blast Design and Optimization Studies Based on Vibration Control for Excavation of Hydropower Stations

    Microsoft Academic Search

    Jin Li; Luo Yi; Zhang Fayong; Zhu Qihu

    2009-01-01

    It makes a systematic summarization on the key points of controlling blasting vibration for hydro-electric projects, including requirements of controlling vibration and prediction of vibration. Then it provides a set of blast design and optimization method on the basis of controlling blasting vibration. At last a case of blasting design by this method is introduced, which is from the project

  12. Application of blast wave theory to explosive propulsion. [system performance analysis

    NASA Technical Reports Server (NTRS)

    Back, L. H.

    1975-01-01

    An analysis was carried out by using blast wave theory to delineate the important aspects of detonating explosives in nozzles, such as flow and wave phenomena, characteristic length and time scales, and the parameters on which the specific impulse is dependent. The propulsive system utilizes the momentum of the ambient gas set into motion in the nozzle by the explosion. A somewhat simplified model was considered for the situation where the mass of ambient gas in the nozzle is much greater than the mass of gas produced in the explosion, a condition of interest for dense atmospheres, e.g., near the surface of Venus. Instantaneous detonation and energy release was presumed to occur at the apex of a conical nozzle, and the shock wave generated by the explosion was taken to propagate as a spherical wave, thereby setting the ambient gas in the nozzle into one-dimensional radially outward motion.

  13. Study of radiative blast waves generated on the Z-beamlet laser.

    SciTech Connect

    Edens, Aaron D.; Schwarz, Jens

    2012-02-01

    This document describes the original goals of the project to study the Vishniac Overstability on blast waves produced using the Z-Beamlet laser facility as well as the actual results. The proposed work was to build on earlier work on the facility and result in the best characterized set of data for such phenomena in the laboratory. To accomplish the goals it was necessary to modify the existing probe laser at the facility so that it could take multiple images over the course of 1-2 microseconds. Troubles with modifying the probe laser are detailed as well as the work that went into said modifications. The probe laser modification ended up taking the entire length of the project and were the major accomplishment of the research.

  14. The effect of particle feed rate on the plastic media blast jet

    SciTech Connect

    McIntosh, M.J. (Argonne National Lab., IL (United States). Energy Systems Division)

    1992-11-01

    Paint removal from military aircraft is often done by plastic media blasting (PMB): the use of plastic grit in a conventional blast jet. However, there is some concern that PMB will cause damage. To help in evaluating this possibility, a time of flight'' meter is used to measure particle velocity in the jet, as a function of air pressure, distance from the nozzle, and particle feed rate, F. Using the data and a momentum balance, a semi-empirical model relating these variables is developed and used for analysis of the effect of F on the intensity of kinetic energy delivery, E, to a work piece. The analysis shows that F has several important effects on E. These methods and results will be useful for damage studies and in production work.

  15. Thermal-destruction products of coal in the blast-furnace gas-purification system

    SciTech Connect

    A.M. Amdur; M.V. Shibanova; E.V. Ental'tsev [Russian Academy of Sciences, Yekaterinburg (Russian Federation). Russia Institute of Metallurgy

    2008-10-15

    The lean, poorly clinkering coal and anthracite used to replace coke in blast furnaces has a considerable content of volatile components (low-molecular thermaldestruction products), which enter the water and sludge of the blast-furnace gas-purification system as petroleum products. Therefore, it is important to study the influence of coal on the petroleum-product content in the water and sludge within this system. The liberation of primary thermal-destruction products is investigated for anthracite with around 4 wt % volatiles, using a STA 449C Jupiter thermoanalyzer equipped with a QMC 230 mass spectrometer. The thermoanalyzer determines small changes in mass and thermal effects with high accuracy (weighing accuracy 10{sup -8} g; error in measuring thermal effects 1 mV). This permits experiments with single layers of coal particles, eliminating secondary reactions of its thermal-destruction products.

  16. High Prevalence of Chronic Pituitary and Target-Organ Hormone Abnormalities after Blast-Related Mild Traumatic Brain Injury

    PubMed Central

    Wilkinson, Charles W.; Pagulayan, Kathleen F.; Petrie, Eric C.; Mayer, Cynthia L.; Colasurdo, Elizabeth A.; Shofer, Jane B.; Hart, Kim L.; Hoff, David; Tarabochia, Matthew A.; Peskind, Elaine R.

    2011-01-01

    Studies of traumatic brain injury from all causes have found evidence of chronic hypopituitarism, defined by deficient production of one or more pituitary hormones at least 1?year after injury, in 25–50% of cases. Most studies found the occurrence of posttraumatic hypopituitarism (PTHP) to be unrelated to injury severity. Growth hormone deficiency (GHD) and hypogonadism were reported most frequently. Hypopituitarism, and in particular adult GHD, is associated with symptoms that resemble those of PTSD, including fatigue, anxiety, depression, irritability, insomnia, sexual dysfunction, cognitive deficiencies, and decreased quality of life. However, the prevalence of PTHP after blast-related mild TBI (mTBI), an extremely common injury in modern military operations, has not been characterized. We measured concentrations of 12 pituitary and target-organ hormones in two groups of male US Veterans of combat in Iraq or Afghanistan. One group consisted of participants with blast-related mTBI whose last blast exposure was at least 1?year prior to the study. The other consisted of Veterans with similar military deployment histories but without blast exposure. Eleven of 26, or 42% of participants with blast concussions were found to have abnormal hormone levels in one or more pituitary axes, a prevalence similar to that found in other forms of TBI. Five members of the mTBI group were found with markedly low age-adjusted insulin-like growth factor-I (IGF-I) levels indicative of probable GHD, and three had testosterone and gonadotropin concentrations consistent with hypogonadism. If symptoms characteristic of both PTHP and PTSD can be linked to pituitary dysfunction, they may be amenable to treatment with hormone replacement. Routine screening for chronic hypopituitarism after blast concussion shows promise for appropriately directing diagnostic and therapeutic decisions that otherwise may remain unconsidered and for markedly facilitating recovery and rehabilitation. PMID:22347210

  17. Ultra fast all-optical fiber pressure sensor for blast event evaluation

    NASA Astrophysics Data System (ADS)

    Wu, Nan; Wang, Wenhui; Tian, Ye; Niezrecki, Christopher; Wang, Xingwei

    2011-05-01

    Traumatic brain injury (TBI) is a great potential threat to soldiers who are exposed to explosions or athletes who receive cranial impacts. Protecting people from TBI has recently attracted a significant amount of attention due to recent military operations in the Middle East. Recording pressure transient data in a blast event is very critical to the understanding of the effects of blast events on TBI. However, due to the fast change of the pressure during blast events, very few sensors have the capability to effectively track the dynamic pressure transients. This paper reports an ultra fast, miniature and all-optical fiber pressure sensor which could be mounted at different locations of a helmet to measure the fast changing pressure simultaneously. The sensor is based on Fabry-Perot (FP) principle. The end face of the fiber is wet etched. A well controlled thickness silicon dioxide diaphragm is thermal bonded on the end face to form an FP cavity. A shock tube test was conducted at Natick Soldier Research Development and Engineering Center, where the sensors were mounted in a shock tube side by side with a reference sensor to measure the rapidly changing pressure. The results of the test demonstrated that the sensor developed had an improved rise time (shorter than 0.4 ?s) when compared to a commercially available reference sensor.

  18. BLAST OBSERVATIONS OF THE SOUTH ECLIPTIC POLE FIELD: NUMBER COUNTS AND SOURCE CATALOGS

    SciTech Connect

    Valiante, Elisabetta; Braglia, Filiberto G.; Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen; Scott, Douglas [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Ade, Peter A. R.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip; Pascale, Enzo [Department of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff, CF24 3AA (United Kingdom); Bock, James J. [Jet Propulsion Laboratory, Pasadena, CA 91109-8099 (United States); Devlin, Mark J.; Klein, Jeff [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Gundersen, Joshua O. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Carol Gables, FL 33146 (United States); Hughes, David H. [Instituto Nacional de Astrofisica Optica y Electronica (INAOE), Aptdo. Postal 51 y 72000 Puebla (Mexico); Netterfield, Calvin B. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Olmi, Luca [Istituto di Radioastronomia, Largo E. Fermi 5, I-50125, Firenze (Italy); Patanchon, Guillaume [Laboratoire APC, 10, rue Alice Domon et Leonie Duquet 75205 Paris (France); Rex, Marie, E-mail: valiante@phas.ubc.c [Steward Observatory, University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85721 (United States)

    2010-12-15

    We present results from a survey carried out by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) on a 9 deg{sup 2} field near the South Ecliptic Pole at 250, 350, and 500 {mu}m. The median 1{sigma} depths of the maps are 36.0, 26.4, and 18.4 mJy, respectively. We apply a statistical method to estimate submillimeter galaxy number counts and find that they are in agreement with other measurements made with the same instrument and with the more recent results from Herschel/SPIRE. Thanks to the large field observed, the new measurements give additional constraints on the bright end of the counts. We identify 132, 89, and 61 sources with S/N {>=}4 at 250, 350, 500 {mu}m, respectively and provide a multi-wavelength combined catalog of 232 sources with a significance {>=}4{sigma} in at least one BLAST band. The new BLAST maps and catalogs are available publicly at http://blastexperiment.info.

  19. Blast-induced electromagnetic fields in the brain from bone piezoelectricity.

    PubMed

    Lee, Ka Yan Karen; Nyein, Michelle K; Moore, David F; Joannopoulos, J D; Socrate, Simona; Imholt, Timothy; Radovitzky, Raul; Johnson, Steven G

    2011-01-01

    In this paper, we show that bone piezoelectricity-a phenomenon in which bone polarizes electrically in response to an applied mechanical stress and produces a short-range electric field-may be a source of intense blast-induced electric fields in the brain, with magnitudes and timescales comparable to fields with known neurological effects. We compute the induced charge density in the skull from stress data on the skull from a finite-element full-head model simulation of a typical IED-scale blast wave incident on an unhelmeted human head as well as a human head protected by a kevlar helmet, and estimate the resulting electric fields in the brain in both cases to be on the order of 10 V/m in millisecond pulses. These fields are more than 10 times stronger than the IEEE safety guidelines for controlled environments (IEEE Standards Coordinating Committee 28, 2002) and comparable in strength and timescale to fields from repetitive Transcranial Magnetic Stimulation (rTMS) that are designed to induce neurological effects (Wagner et al., 2006a). They can be easily measured by RF antennas, and may provide the means to design a diagnostic tool that records a quantitative measure of the head's exposure to blast insult. PMID:20547228

  20. Extended adiabatic blast waves and a model of the soft X-ray background

    NASA Technical Reports Server (NTRS)

    Cox, D. P.; Anderson, P. R.

    1982-01-01

    The suggestion has been made that much of the soft X-ray background observed in X-ray astronomy might arise from being inside a very large supernova blast wave propagating in the hot, low-density component of the interstellar (ISM) medium. An investigation is conducted to study this possibility. An analytic approximation is presented for the nonsimilar time evolution of the dynamic structure of an adiabatic blast wave generated by a point explosion in a homogeneous ambient medium. A scheme is provided for evaluating the electron-temperature distribution for the evolving structure, and a procedure is presented for following the state of a given fluid element through the evolving dynamical and thermal structures. The results of the investigation show that, if the solar system were located within a blast wave, the Wisconsin soft X-ray rocket payload would measure the B and C band count rates that it does measure, provided conditions correspond to the values calculated in the investigation.

  1. Transport phenomena in porous media

    NASA Astrophysics Data System (ADS)

    Bear, Jacob; Corapcioglu, M. Yavuz

    The Advanced Study Institute on Fundamentals of Transport Phenomena in Porous Media, held July 14-23, 1985 in Newark, Del. and directed by Jacob Bear (Israel Institute of Technology, Haifa) and M. Yavuz Corapcioglu (City College of New York), under the auspices of NATO, was a sequel to the NATO Advanced Study Institute (ASI) held in 1982 (proceedings published as Fundamentals of Transport Phenomena in Porous Media, J. Bear, and M.Y. Corapcioglu (Ed.), Martinus Nijhoff, Dordrecht, the Netherlands, 1984). The meeting was attended by 106 participants and lecturers from 21 countries.As in the first NATO/ASI, the objective of this meeting—which was a combination of a conference of experts and a teaching institute— was to present and discuss selected topics of transport in porous media. In selecting topics and lecturers, an attempt was made to bridge the gap that sometimes exists between research and practice. An effort was also made to demonstrate the unified approach to the transport of mass of a fluid phase, components of a fluid phase, momentum, and heat in a porous medium domain. The void space may be occupied by a single fluid phase or by a number of such phases; each fluid may constitute a multicomponent system; the solid matrix may be deformable; and the whole process of transport in the system may take place under nonisothermal conditions, with or without phase changes. Such phenomena are encountered in a variety of disciplines, e.g., petroleum engineering, civil engineering (in connection with groundwater flow and contamination), soil mechanics, and chemical engineering. One of the goals of the 1985 NATO/ASI, as in the 1982 institute, was to bring together experts from all these disciplines and enhance communication among them.

  2. Irradiation-induced phenomena in carbon

    E-print Network

    Krasheninnikov, Arkady V.

    Chapter 1 Irradiation-induced phenomena in carbon nanotubes To appear in "Chemistry of Carbon@acclab.helsinki.fi 1 #12;2CHAPTER 1. IRRADIATION-INDUCED PHENOMENA IN CARBON NANOTUBES #12;Contents 1 Irradiation-induced phenomena in carbon nanotubes 1 1.1 Introduction

  3. Natural phenomena hazards, Hanford Site, Washington

    SciTech Connect

    Conrads, T.J.

    1998-09-29

    This document presents the natural phenomena hazard loads for use in implementing DOE Order 5480.28, Natural Phenomena Hazards Mitigation, and supports development of double-shell tank systems specifications at the Hanford Site in south-central Washington State. The natural phenomena covered are seismic, flood, wind, volcanic ash, lightning, snow, temperature, solar radiation, suspended sediment, and relative humidity.

  4. Phenomena and Diosignes of Aratous

    NASA Astrophysics Data System (ADS)

    Avgoloupis, S. I.

    2013-01-01

    Aratous (305-240B.C.) was a singular intellectual, writer and poet which engage himself to compose a very interesting astronomical poet, using the "Dactylous sixstage' style, the formal style of the ancient Greek Epic poetry. This astronomic poem of Aratous "Phenomena and Diosignes" became very favorite reading during the Alexandrine, the Romman and the Byzandin eras as well and had received many praises from significant poets and particularly from Hipparchous and from Theonas from Alexandria, an astronomer of 4rth century A.C.(in Greeks)

  5. Gravitational anomaly and transport phenomena.

    PubMed

    Landsteiner, Karl; Megías, Eugenio; Pena-Benitez, Francisco

    2011-07-01

    Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid. PMID:21797593

  6. PSYCHIATRIC MORBIDITY AMONG VICTIMS OF BOMB BLAST

    PubMed Central

    Gautam, Shiv; Gupta, I.D.; Batra, Lalit; Sharma, Himanshiu; Khandelwal, Rakesh; Pant, Anshuman

    1998-01-01

    Thirty one victims of bomb blast in a bus caused by terrorist activity in Dausa district, Rajasthan on 22.5.96, were evaluated for psychological reactions 3 days & 2 weeks after the incident. All hospitalized & non hospitalised bomb blast victims were assessed within 3 days of injury by objective predictors (percent of burnt area, facial disfigurement, limb amputations, fractures etc.) and subjective predictors (emotional distress and perceived social support). Detailed history, physical and mental state examination of all patients was carried out and for those having scores more then 17 on GHQ-60 (Hindi version), IPIS was administered. Diagnosis was made by 3 senior consultant psychiatrists of Psychiatric Centre, Jaipur, on the basis oflCD-10. At day 3 of 31 patients studied 11 (35.45%) had psychiatric morbidity. Out of which 6 (19.35%) had acute stress reaction, 3 (9.68%) had depression and 2 (6.45%) dissociative amnesia. Most commonly reported symptoms on IPIS were depersonalisation, derealisation, sleep disturbances specially generalised sleep loss, loss of appetite, nightmares, situational anxiety, depression, mental irritability, dulness of feelings, self blame, guilt, loss of interest, suicidal ideas, and worry about money, spouse, work and children. Most common physical injury was burns, followed by hearing disturbances, wounds received due to glass <& metal pieces and non specific pains and aches. Findings of follow up have been discussed and battery of tests for evaluation of victims of acute trauma has been suggested. PMID:21494441

  7. Computation of viscous blast wave flowfields

    NASA Technical Reports Server (NTRS)

    Atwood, Christopher A.

    1991-01-01

    A method to determine unsteady solutions of the Navier-Stokes equations was developed and applied. The structural finite-volume, approximately factored implicit scheme uses Newton subiterations to obtain the spatially and temporally second-order accurate time history of the interaction of blast-waves with stationary targets. The inviscid flux is evaluated using MacCormack's modified Steger-Warming flux or Roe flux difference splittings with total variation diminishing limiters, while the viscous flux is computed using central differences. The use of implicit boundary conditions in conjunction with a telescoping in time and space method permitted solutions to this strongly unsteady class of problems. Comparisons of numerical, analytical, and experimental results were made in two and three dimensions. These comparisons revealed accurate wave speed resolution with nonoscillatory discontinuity capturing. The purpose of this effort was to address the three-dimensional, viscous blast-wave problem. Test cases were undertaken to reveal these methods' weaknesses in three regimes: (1) viscous-dominated flow; (2) complex unsteady flow; and (3) three-dimensional flow. Comparisons of these computations to analytic and experimental results provided initial validation of the resultant code. Addition details on the numerical method and on the validation can be found in the appendix. Presently, the code is capable of single zone computations with selection of any permutation of solid wall or flow-through boundaries.

  8. Genetic dissection of rice blast resistance by QTL mapping approach using an F3 population.

    PubMed

    Ashkani, S; Rafii, M Y; Rahim, H A; Latif, M A

    2013-03-01

    Rice blast is one of the major fungal diseases that badly reduce rice production in Asia including Malaysia. There is not much information on identification of QTLs as well as linked markers and their association with blast resistance within local rice cultivars. In order to understanding of the genetic control of blast in the F3 families from indica rice cross Pongsu seribu2/Mahsuri, an analysis of quantitative trait loci against one of the highly virulent Malaysian rice blast isolate Magnaporthe oryzae, P5.0 was carried out. Result indicated that partial resistance to this pathotype observed in the present study was controlled by multiple loci or different QTLs. In QTL analysis in F3 progeny fifteen QTLs on chromosomes 1, 2, 3, 5, 6, 11 and 12 for resistance to blast nursery tests was identified. Three of detected QTLs (qRBr-6.1, qRBr-11.4, and qRBr-12.1) had significant threshold (LOD >3) and approved by both IM and CIM methods. Twelve suggestive QTLs, qRBr-1.2, qRBr-2.1, qRBr-4.1, qRBr-5.1, qRBr-6.2, qRBr-6.3, qRBr-8.1, qRBr-10.1, qRBr-10.2, qRBr-11.1, qRBr-11.2 and qRBr-11.3) with Logarithmic of Odds (LOD) <3.0 or LRS <15) were distributed on chromosomes 1, 2, 4, 5, 6, 8, 10, and 11. Most of the QTLs detected using single isolate had the resistant alleles from Pongsu seribu 2 which involved in the resistance in the greenhouse. We found that QTLs detected for deferent traits for the using isolate were frequently located in similar genomic regions. Inheritance study showed among F3 lines resistance segregated in the expected ratio of 15: 1 for resistant to susceptible. The average score for blast resistance measured in the green house was 3.15, 1.98 and 29.95 % for three traits, BLD, BLT and % DLA, respectively. PMID:23203411

  9. The physical properties of the blast wave produced by a stoichiometric propane/oxygen explosion

    NASA Astrophysics Data System (ADS)

    Dewey, M. C.; Dewey, J. M.

    2014-07-01

    The trajectory of the primary shock produced by the explosion of a nominal 18.14 t (20 tn) hemispherical propane/oxygen charge was analysed previously to provide the physical properties immediately behind the shock, but gave no information about the time-resolved properties throughout the blast wave. The present study maps all the physical properties of the wave throughout and beyond the positive durations for a range of distances from about 1.6-18 m scaled to a 1 kg charge at NTP. The physical properties were calculated using a hydro-code to simulate the flow field produced by a spherical piston moving with a specific trajectory. This technique has been used extensively to determine the physical properties of blast waves from a variety of sources for which the piston path was determined by high-speed photography of smoke tracers established close to the charges immediately before detonation. In the case of the propane/oxygen explosion, smoke tracer data were not available to determine the trajectory of the spherical piston. An arbitrary piston path was used and its trajectory iteratively adjusted until it produced a blast wave with a primary shock whose trajectory exactly matched the measured trajectory from the propane/oxygen explosion. Throughout the studied flow field the time histories of hydrostatic pressure, density and particle velocity are well described by fits to the modified Friedlander equation. The properties are presented as functions of scaled radius and are compared with the properties of the blast wave from a 1 kg TNT surface burst explosion, and with other measurements of the same explosion.

  10. The physical properties of the blast wave produced by a stoichiometric propane/oxygen explosion

    NASA Astrophysics Data System (ADS)

    Dewey, M. C.; Dewey, J. M.

    2014-11-01

    The trajectory of the primary shock produced by the explosion of a nominal 18.14 t (20 tn) hemispherical propane/oxygen charge was analysed previously to provide the physical properties immediately behind the shock, but gave no information about the time-resolved properties throughout the blast wave. The present study maps all the physical properties of the wave throughout and beyond the positive durations for a range of distances from about 1.6-18 m scaled to a 1 kg charge at NTP. The physical properties were calculated using a hydro-code to simulate the flow field produced by a spherical piston moving with a specific trajectory. This technique has been used extensively to determine the physical properties of blast waves from a variety of sources for which the piston path was determined by high-speed photography of smoke tracers established close to the charges immediately before detonation. In the case of the propane/oxygen explosion, smoke tracer data were not available to determine the trajectory of the spherical piston. An arbitrary piston path was used and its trajectory iteratively adjusted until it produced a blast wave with a primary shock whose trajectory exactly matched the measured trajectory from the propane/oxygen explosion. Throughout the studied flow field the time histories of hydrostatic pressure, density and particle velocity are well described by fits to the modified Friedlander equation. The properties are presented as functions of scaled radius and are compared with the properties of the blast wave from a 1 kg TNT surface burst explosion, and with other measurements of the same explosion.

  11. Studies of Novel Quantum Phenomena in Ruthenates

    SciTech Connect

    Mao, Zhiqiang

    2011-04-08

    Strongly correlated oxides have been the subject of intense study in contemporary condensed matter physics, and perovskite ruthenates (Sr,Ca)n+1RunO3n+1 have become a new focus in this field. One of important characteristics of ruthenates is that both lattice and orbital degrees of freedom are active and are strongly coupled to charge and spin degrees of freedom. Such a complex interplay of multiple degrees of freedom causes the properties of ruthenates to exhibit a gigantic response to external stimuli under certain circumstances. Magnetic field, pressure, and chemical composition all have been demonstrated to be effective in inducing electronic/magnetic phase transitions in ruthenates. Therefore, ruthenates are ideal candidates for searching for novel quantum phenomena through controlling external parameters. The objective of this project is to search for novel quantum phenomena in ruthenate materials using high-quality single crystals grown by the floating-zone technique, and investigate the underlying physics. The following summarizes our accomplishments. We have focused on trilayered Sr4Ru3O10 and bilayered (Ca1-xSrx)3Ru2O7. We have succeeded in growing high-quality single crystals of these materials using the floating-zone technique and performed systematic studies on their electronic and magnetic properties through a variety of measurements, including resistivity, Hall coefficient, angle-resolved magnetoresistivity, Hall probe microscopy, and specific heat. We have also studied microscopic magnetic properties for some of these materials using neutron scattering in collaboration with Los Alamos National Laboratory. We have observed a number of unusual exotic quantum phenomena through these studies, such as an orbital selective metamagnetic transition, bulk spin valve effect, and a heavy-mass nearly ferromagnetic state with a surprisingly large Wilson ratio. Our work has also revealed underlying physics of these exotic phenomena. Exotic phenomena of correlated electron has been among central topics of contempary condensed matter physics. Ultrfast phase transitions accompanied by switching of conductivity or magnetization in stronly correlated materials are believed to be promising in developing next generation of transistors. Our work on layered ruthenates has remarkably advanced our understanding of how the exotic phenomena of correlated electrons is governed by the complex interplay between charge, spin, lattice and orbital degrees of freedom. In addition to studies on ruthenates, we have also expanded our research to the emerging field of Fe-based superconductors, focusing on the iron chalcogenide Fe1+y(Te1-xSex) superconductor system. We first studied the superconductivity of this alloy system following the discovery of superconductivity in FeSe using polycrystalline samples. Later, we successfuly grew high-quality single crystals of these materials. Using these single crystals, we have determined the magnetic structure of the parent compound Fe1+yTe, observed spin resonance of superconducting state in optimally doped samples, and established a phase diagram. Our work has produced an important impact in this burgeoning field. The PI presented an invited talk on this topic at APS March meeting in 2010. We have published 19 papers in these two areas (one in Nature materials, five in Physical Review Letters, and nine in Physical Review B) and submitted two (see the list of publications attached below).

  12. Simulation of blast-induced, early-time intracranial wave physics leading to traumatic brain injury.

    SciTech Connect

    Taylor, Paul Allen; Ford, Corey C. (University of New Mexico, Albuquerque, NM)

    2008-04-01

    U.S. soldiers are surviving blast and impacts due to effective body armor, trauma evacuation and care. Blast injuries are the leading cause of traumatic brain injury (TBI) in military personnel returning from combat. Understanding of Primary Blast Injury may be needed to develop better means of blast mitigation strategies. The objective of this paper is to investigate the effects of blast direction and strength on the resulting mechanical stress and wave energy distributions generated in the brain.

  13. LTC vacuum blasting maching (concrete): Baseline report: Greenbook (Chapter)

    SciTech Connect

    NONE

    1997-07-31

    The LTC shot blast technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjuction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The LTC 1073 Vacuum Blasting Machine uses a high-capacity, direct-pressure blasting system which incorporates a continuous feed for the blast media. The blast media cleans the surface within the contained brush area of the blast. It incorporates a vacuum system which removes dust and debris from the surface as it is blasted. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure during maintenance activities was minimal, but due to mechanical difficulties dust monitoring could not be conducted during operation. Noise exposure was significant. Further testing for each of these exposures is recommended because of the outdoor environment where the testing demonstration took place. This may cause the results to be inaccurate. It is feasible that the dust and noise levels will be higher in an enclosed environment. In addition, other safety and health issues found were ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, and arm-hand vibration.

  14. Explosively driven air blast in a conical shock tube

    NASA Astrophysics Data System (ADS)

    Stewart, Joel B.; Pecora, Collin

    2015-03-01

    Explosively driven shock tubes present challenges in terms of safety concerns and expensive upkeep of test facilities but provide more realistic approximations to the air blast resulting from free-field detonations than those provided by gas-driven shock tubes. Likewise, the geometry of conical shock tubes can naturally approximate a sector cut from a spherically symmetric blast, leading to a better agreement with the blast profiles of free-field detonations when compared to those provided by shock tubes employing constant cross sections. The work presented in this article documents the design, fabrication, and testing of an explosively driven conical shock tube whose goal was to closely replicate the blast profile seen from a larger, free-field detonation. By constraining the blast through a finite area, large blasts (which can add significant damage and safety constraints) can be simulated using smaller explosive charges. The experimental data presented herein show that a close approximation to the free-field air blast profile due to a 1.5 lb charge of C4 at 76 in. can be achieved by using a 0.032 lb charge in a 76-in.-long conical shock tube (which translates to an amplification factor of nearly 50). Modeling and simulation tools were used extensively in designing this shock tube to minimize expensive fabrication costs.

  15. Spectrum of abdominal organ injury in a primary blast type

    PubMed Central

    2009-01-01

    Introduction Abdominal organ injury in a primary blast type is always challenging for diagnosis. Air containing abdominal viscera is most vulnerable to effects of primary blast injury. In any patient exposed to a primary blast wave who presents with an acute abdomen, an abdominal organ injury is to be kept in a clinical suspicion. Aim Study various abdominal organ injuries occurring in a primary type of blast injury. Material and methods: All those who had exploratory laparotomy for abdominal organ injuries after a primary blast injury for a period of 10 years from January 1998 - January 2008 were included in this retrospective study. Results Total 154 patients had laparotomy for abdominal organ injuries with a primary blast type of injury. Small intestine was damaged in 48 patients (31.1%) followed by spleen in 22.7% cases. 54 patients (35.06%) had more than one organ injured. Liver laceration was present in 30 patients (19.48%). Multiple small gut perforations were present in 37 patients (77.08%). Negative laparotomy was found in 5 patients (3.24%) whereas 3 (1.94%) had re-exploration. Mortality was present in 6 patients (3.89%). Conclusions Primary blast injury causes varied abdominal organ injuries. Single or multiple organ damage can be there. Small intestine is commonest viscera injured. Laparotomy gives final diagnosis. PMID:20025766

  16. Celestial Blast in Bleak Reticulum

    NASA Astrophysics Data System (ADS)

    2005-08-01

    The southern Reticulum constellation [1] certainly isn't a big hit for amateur astronomers. This tiny, bleak and diamond-shaped constellation, not far on the sky from the Large Magellanic Cloud, is often overlooked. But recently, astronomers had a closer look at a galaxy situated inside it. And more precisely at an exploding star hosted by the spiral galaxy NGC 1559 [2]. On the night of August 4, 2005, the renowned Australian amateur astronomer and SN discoverer Reverend Robert Evans discovered a supernova just North of the galaxy with his 0.31-m telescope. The supernova - the explosion of a star - was of magnitude 13.8, that is, only 20 times fainter than the entire host galaxy. Being the 104th supernova discovered in 2005, it received the name SN 2005df. Notably, Evans had already discovered 2 other supernovae in the same galaxy: in 1984 (SN 1984J) and in 1986 (SN 1986L). The following night, astronomer Marilena Salvo and her Australian colleagues classified the supernova as a somewhat unusual type Ia supernova, caught probably 10 days before it reached its maximum brightness. Such a supernova is thought to be the result of the explosion of a small and dense star - a white dwarf [3] - inside a binary system. As its companion was continuously spilling matter onto the white dwarf, the white dwarf reached a critical mass, leading to a fatal instability and the supernova. These are exactly a kind of supernovae in which Dietrich Baade, Ferdinando Patat (ESO), Lifan Wang (Lawrence Berkeley National Laboratory, USA), and their colleagues are interested. In particular, they study the polarization properties of this kind of supernova in order to learn more about their asphericity, which holds important clues to the detailed physics that governs this terminal catastrophe in the life of such stars. Having an accepted observing programme that uses the FORS1 multi-mode instrument on Kueyen, one of the four Unit Telescopes of ESO's 8.2m Very Large Telescope at Cerro Paranal, they triggered a Target of Opportunity request so that on-duty astronomers at the VLT could observe this supernova, which was done on August 6. From a very first analysis of their data, Wang and his colleagues found that SN 2005df resembles closely another supernova they had studied before, SN 2001el, whose explosion they showed was significantly asymmetric (see ESO PR 23/03). NGC 1559 is a SBc(s)-type spiral galaxy [4] located about 50 million light-years away, that weighs the equivalent of about 10,000 million of suns, and is about 7 times smaller than our Milky Way: on the sky, it measures about 4x2 arcmin2. Receding from us at a speed of about 1,300 km/s, it is a galaxy of the Seyfert type. Such galaxies are characterized by a bright nucleus that radiates strongly in the blue and in the ultraviolet. Astronomers think that about 2 solar masses of gas per year are transformed into stars in this galaxy. Like most galaxies, NGC 1559 probably contains a black hole in its centre, which should have a mass that is equivalent to 300,000 suns. Technical Information: ESO PR Photo 26/05 is a composite based on four images taken with FORS1 on Kueyen (VLT) by Paul Vreeswijk, Dominique Naef and Chris Lidman (ESO) for Dietrich Baade, Ferdinando Patat, and Lifan Wang. The images were taken through different filters: V, R, I, and a narrow-band filter centred on the H-alpha line. The exposure time is 60 seconds in the three broad-band filters (V, R and I) and 3 min in the H-alpha filter. The field of view is 5.5 x 4.7 arcmin2. North is up and East is to the left.

  17. Uranium Pyrophoricity Phenomena and Prediction

    SciTech Connect

    DUNCAN, D.R.

    2000-04-20

    We have compiled a topical reference on the phenomena, experiences, experiments, and prediction of uranium pyrophoricity for the Hanford Spent Nuclear Fuel Project (SNFP) with specific applications to SNFP process and situations. The purpose of the compilation is to create a reference to integrate and preserve this knowledge. Decades ago, uranium and zirconium fires were commonplace at Atomic Energy Commission facilities, and good documentation of experiences is surprisingly sparse. Today, these phenomena are important to site remediation and analysis of packaging, transportation, and processing of unirradiated metal scrap and spent nuclear fuel. Our document, bearing the same title as this paper, will soon be available in the Hanford document system [Plys, et al., 2000]. This paper explains general content of our topical reference and provides examples useful throughout the DOE complex. Moreover, the methods described here can be applied to analysis of potentially pyrophoric plutonium, metal, or metal hydride compounds provided that kinetic data are available. A key feature of this paper is a set of straightforward equations and values that are immediately applicable to safety analysis.

  18. Compressive strength after blast of sandwich composite materials

    PubMed Central

    Arora, H.; Kelly, M.; Worley, A.; Del Linz, P.; Fergusson, A.; Hooper, P. A.; Dear, J. P.

    2014-01-01

    Composite sandwich materials have yet to be widely adopted in the construction of naval vessels despite their excellent strength-to-weight ratio and low radar return. One barrier to their wider use is our limited understanding of their performance when subjected to air blast. This paper focuses on this problem and specifically the strength remaining after damage caused during an explosion. Carbon-fibre-reinforced polymer (CFRP) composite skins on a styrene–acrylonitrile (SAN) polymer closed-cell foam core are the primary composite system evaluated. Glass-fibre-reinforced polymer (GFRP) composite skins were also included for comparison in a comparable sandwich configuration. Full-scale blast experiments were conducted, where 1.6×1.3?m sized panels were subjected to blast of a Hopkinson–Cranz scaled distance of 3.02?m?kg?1/3, 100?kg TNT equivalent at a stand-off distance of 14?m. This explosive blast represents a surface blast threat, where the shockwave propagates in air towards the naval vessel. Hopkinson was the first to investigate the characteristics of this explosive air-blast pulse (Hopkinson 1948 Proc. R. Soc. Lond. A 89, 411–413 (doi:10.1098/rspa.1914.0008)). Further analysis is provided on the performance of the CFRP sandwich panel relative to the GFRP sandwich panel when subjected to blast loading through use of high-speed speckle strain mapping. After the blast events, the residual compressive load-bearing capacity is investigated experimentally, using appropriate loading conditions that an in-service vessel may have to sustain. Residual strength testing is well established for post-impact ballistic assessment, but there has been less research performed on the residual strength of sandwich composites after blast. PMID:24711494

  19. Compressive strength after blast of sandwich composite materials.

    PubMed

    Arora, H; Kelly, M; Worley, A; Del Linz, P; Fergusson, A; Hooper, P A; Dear, J P

    2014-05-13

    Composite sandwich materials have yet to be widely adopted in the construction of naval vessels despite their excellent strength-to-weight ratio and low radar return. One barrier to their wider use is our limited understanding of their performance when subjected to air blast. This paper focuses on this problem and specifically the strength remaining after damage caused during an explosion. Carbon-fibre-reinforced polymer (CFRP) composite skins on a styrene-acrylonitrile (SAN) polymer closed-cell foam core are the primary composite system evaluated. Glass-fibre-reinforced polymer (GFRP) composite skins were also included for comparison in a comparable sandwich configuration. Full-scale blast experiments were conducted, where 1.6×1.3?m sized panels were subjected to blast of a Hopkinson-Cranz scaled distance of 3.02?m?kg(-1/3), 100?kg TNT equivalent at a stand-off distance of 14?m. This explosive blast represents a surface blast threat, where the shockwave propagates in air towards the naval vessel. Hopkinson was the first to investigate the characteristics of this explosive air-blast pulse (Hopkinson 1948 Proc. R. Soc. Lond. A 89, 411-413 (doi:10.1098/rspa.1914.0008)). Further analysis is provided on the performance of the CFRP sandwich panel relative to the GFRP sandwich panel when subjected to blast loading through use of high-speed speckle strain mapping. After the blast events, the residual compressive load-bearing capacity is investigated experimentally, using appropriate loading conditions that an in-service vessel may have to sustain. Residual strength testing is well established for post-impact ballistic assessment, but there has been less research performed on the residual strength of sandwich composites after blast. PMID:24711494

  20. Low Level Primary Blast Injury in Rodent Brain

    PubMed Central

    Pun, Pamela B. L.; Kan, Enci Mary; Salim, Agus; Li, Zhaohui; Ng, Kian Chye; Moochhala, Shabbir M.; Ling, Eng-Ang; Tan, Mui Hong; Lu, Jia

    2011-01-01

    The incidence of blast attacks and resulting traumatic brain injuries has been on the rise in recent years. Primary blast is one of the mechanisms in which the blast wave can cause injury to the brain. The aim of this study was to investigate the effects of a single sub-lethal blast over pressure (BOP) exposure of either 48.9?kPa (7.1?psi) or 77.3?kPa (11.3?psi) to rodents in an open-field setting. Brain tissue from these rats was harvested for microarray and histopathological analyses. Gross histopathology of the brains showed that cortical neurons were “darkened” and shrunken with narrowed vasculature in the cerebral cortex day 1 after blast with signs of recovery at day 4 and day 7 after blast. TUNEL-positive cells were predominant in the white matter of the brain at day 1 after blast and double-labeling of brain tissue showed that these DNA-damaged cells were both oligodendrocytes and astrocytes but were mainly not apoptotic due to the low caspase-3 immunopositivity. There was also an increase in amyloid precursor protein immunoreactive cells in the white matter which suggests acute axonal damage. In contrast, Iba-1 staining for macrophages or microglia was not different from control post-blast. Blast exposure altered the expression of over 5786 genes in the brain which occurred mostly at day 1 and day 4 post-blast. These genes were narrowed down to 10 overlapping genes after time-course evaluation and functional analyses. These genes pointed toward signs of repair at day 4 and day 7 post-blast. Our findings suggest that the BOP levels in the study resulted in mild cellular injury to the brain as evidenced by acute neuronal, cerebrovascular, and white matter perturbations that showed signs of resolution. It is unclear whether these perturbations exist at a milder level or normalize completely and will need more investigation. Specific changes in gene expression may be further evaluated to understand the mechanism of blast-induced neurotrauma. PMID:21541261

  1. Underwater blast loading of a composite twisted rudder with FBGs

    NASA Astrophysics Data System (ADS)

    Seaver, Mark; Trickey, Stephen T.

    2008-04-01

    32 Fiber Bragg gratings (FBGs) were embedded in a full size, composite twisted rudder to monitor internal strains during underwater blast loading. During final fabrication, the fibers leading to sensors were broken rendering the embedded sensors useless. Time domain reflectometry located the breaks and suggested a likely approach to avoiding such problems in the future. An additional 8 FBGs were surface mounted on the rudder and used to collect data during the blast loading events. Data were successfully collected at rates up to 9700 Hz during 3 blasts, with strains approaching 4000 ?? and strain rates of up to 13 ?/s.

  2. Lateral blasts at Mount St. Helens and hazard zonation

    USGS Publications Warehouse

    Crandell, D.R.; Hoblitt, R.P.

    1986-01-01

    Lateral blasts at andesitic and dacitic volcanoes can produce a variety of direct hazards, including ballistic projectiles which can be thrown to distances of at least 10 km and pyroclastic density flows which can travel at high speed to distances of more than 30 km. Indirect effect that may accompany such explosions include wind-borne ash, pyroclastic flows formed by the remobilization of rock debris thrown onto sloping ground, and lahars. Two lateral blasts occurred at a lava dome on the north flank of Mount St. Helens about 1200 years ago; the more energetic of these threw rock debris northeastward across a sector of about 30?? to a distance of at least 10 km. The ballistic debris fell onto an area estimated to be 50 km2, and wind-transported ash and lapilli derived from the lateral-blast cloud fell on an additional lobate area of at least 200 km2. In contrast, the vastly larger lateral blast of May 18, 1980, created a devastating pyroclastic density flow that covered a sector of as much as 180??, reached a maximum distance of 28 km, and within a few minutes directly affected an area of about 550 km2. The May 18 lateral blast resulted from the sudden, landslide-induced depressurization of a dacite cryptodome and the hydrothermal system that surrounded it within the volcano. We propose that lateral-blast hazard assessments for lava domes include an adjoining hazard zone with a radius of at least 10 km. Although a lateral blast can occur on any side of a dome, the sector directly affected by any one blast probably will be less than 180??. Nevertheless, a circular hazard zone centered on the dome is suggested because of the difficulty of predicting the direction of a lateral blast. For the purpose of long-term land-use planning, a hazard assessment for lateral blasts caused by explosions of magma bodies or pressurized hydrothermal systems within a symmetrical volcano could designate a circular potential hazard area with a radius of 35 km centered on the volcano. For short-term hazard assessments, if seismicity and deformation indicate that magma is moving toward the flank of a volcano, it should be recognized that a landslide could lead to the sudden unloading of a magmatic or hydrothermal system and thereby cause a catastrophic lateral blast. A hazard assessment should assume that a lateral blast could directly affect an area at least 180?? wide to a distance of 35 km from the site of the explosion, irrespective of topography. ?? 1986 Springer-Verlag.

  3. Relativistic blast waves in two dimensions. I - The adiabatic case

    NASA Technical Reports Server (NTRS)

    Shapiro, P. R.

    1979-01-01

    Approximate solutions are presented for the dynamical evolution of strong adiabatic relativistic blast waves which result from a point explosion in an ambient gas in which the density varies both with distance from the explosion center and with polar angle in axisymmetry. Solutions are analytical or quasi-analytical for the extreme relativistic case and numerical for the arbitrarily relativistic case. Some general properties of nonplanar relativistic shocks are also discussed, including the incoherence of spherical ultrarelativistic blast-wave fronts on angular scales greater than the reciprocal of the shock Lorentz factor, as well as the conditions for producing blast-wave acceleration.

  4. Evaluation of copper slag blast media for railcar maintenance

    NASA Technical Reports Server (NTRS)

    Sagers, N. W.; Finlayson, Mack H.

    1989-01-01

    Copper slag was tested as a blasting substitute for zirconium silicate which is used to remove paint from railroad cars. The copper slag tested is less costly, strips paint faster, is produced near the point of need, provides a good bonding surface for paint, and permits the operator to work in a more comfortable position, i.e., standing nearly erect instead of having to crouch. Outdoor blasting with the tested Blackhawk (20 to 40 mesh) copper slag is also environmentally acceptable to the State of Utah. Results of tests for the surface erosion rate with copper slag blasting are included.

  5. Hybrid S2/Carbon Epoxy Composite Armours Under Blast Loads

    NASA Astrophysics Data System (ADS)

    Dolce, F.; Meo, Michele; Wright, A.; French, M.; Bernabei, M.

    2012-06-01

    Civil and military structures, such as helicopters, aircrafts, naval ships, tanks or buildings are susceptible to blast loads as terroristic attacks increases, therefore there is the need to design blast resistant structures. During an explosion the peak pressure produced by shock wave is much greater than the static collapse pressure. Metallic structures usually undergo large plastic deformations absorbing blast energy before reaching equilibrium. Due to their high specific properties, fibre-reinforced polymers are being considered for energy absorption applications in blast resistant armours. A deep insight into the relationship between explosion loads, composite architecture and deformation/fracture behaviour will offer the possibility to design structures with significantly enhanced energy absorption and blast resistance performance. This study presents the results of a numerical investigation aimed at understanding the performance of a hybrid composite (glass/carbon fibre) plate subjected to blast loads using commercial LS-DYNA software. In particular, the paper deals with numerical 3D simulations of damages caused by air blast waves generated by C4 charges on two fully clamped rectangular plates made of steel and hybrid (S2/Carbon) composite, respectively. A Multi Materials Arbitrary Lagrangian Eulerian (MMALE) formulation was used to simulate the shock phenomenon. For the steel plates, the Johnson-Cook material model was employed. For the composite plates both in-plane and out-of-plane failure criteria were employed. In particular, a contact tiebreak formulation with a mixed mode failure criteria was employed to simulate delamination failure. As for the steel plates the results showed that excellent correlation with the experimental data for the two blast load conditions in terms of dynamic and residual deflection for two different C4 charges. For the composite plates the numerical results showed that, as expected, a wider delamination damage was observed for the higher blast loads case. Widespread tensile matrix damage was experienced for both blast load cases, while only for 875 g blast load fiber failure damage was observed. This agrees well with the experimental data showing that the composite panel was not able to resist to the 875 g blast load.

  6. Traumatic brain injury produced by exposure to blasts, a critical problem in current wars: biomarkers, clinical studies, and animal models

    NASA Astrophysics Data System (ADS)

    Dixon, C. Edward

    2011-06-01

    Traumatic brain injury (TBI) resulting from exposure to blast energy released by Improvised Explosive Devices (IEDs) has been recognized as the "signature injury" of Operation Iraqi Freedom and Operation Enduring Freedom. Repeated exposure to mild blasts may produce subtle deficits that are difficult to detect and quantify. Several techniques have been used to detect subtle brain dysfunction including neuropsychological assessments, computerized function testing and neuroimaging. Another approach is based on measurement of biologic substances (e.g. proteins) that are released into the body after a TBI. Recent studies measuring biomarkers in CSF and serum from patients with severe TBI have demonstrated the diagnostic, prognostic, and monitoring potential. Advancement of the field will require 1) biochemical mining for new biomarker candidates, 2) clinical validation of utility, 3) technical advances for more sensitive, portable detectors, 4) novel statistical approach to evaluate multiple biomarkers, and 5) commercialization. Animal models have been developed to simulate elements of blast-relevant TBI including gas-driven shock tubes to generate pressure waves similar to those produced by explosives. These models can reproduce hallmark clinical neuropathological responses such as neuronal degeneration and inflammation, as well as behavioral impairments. An important application of these models is to screen novel therapies and conduct proteomic, genomic, and lipodomic studies to mine for new biomarker candidates specific to blast relevant TBI.

  7. Nitrogen runoff from tunnel blasted rocks--a large-scale test.

    PubMed

    Baekken, Torleif

    2014-06-01

    Eight tunnel blasted rock samples were washed five times in 10 m3 containers to calculate the runoff potential of nitrogen from unexploded remains of the ammonium nitrate slurry explosive in rock piles. During the first wash, 65% of total nitrogen was washed off. The average concentrations of NH4+ and NO3- in the first wash water were 46 mg N/L and 58 mg N/L, respectively, being reduced to 2.5 and 1.2 mg N/L after the last wash. The average runoff of total nitrogen from the blasted rocks was 24.2 g N/ton, being 14.7% of nitrogen in the loaded explosives. pH was high (range 8.1 to 11.8) resulting from shotcrete spill, pushing the NH4+/NH3 equilibrium toward the toxic NH3. The consequences of runoff from blasted rock piles may be damaging for water quality and biology in small recipients, and abatement measures should be assessed. PMID:25109203

  8. Diffusion Tensor Imaging Reveals Acute Subcortical Changes after Mild Blast-Induced Traumatic Brain Injury

    PubMed Central

    Kamnaksh, Alaa; Budde, Matthew D.; Kovesdi, Erzsebet; Long, Joseph B.; Frank, Joseph A.; Agoston, Denes V.

    2014-01-01

    Mild blast-induced traumatic brain injury (mbTBI) poses special diagnostic challenges due to its overlapping symptomatology with other neuropsychiatric conditions and the lack of objective outcome measures. Diffusion tensor imaging (DTI) can potentially provide clinically relevant information toward a differential diagnosis. In this study, we aimed to determine if single and repeated (5 total; administered on consecutive days) mild blast overpressure exposure results in detectable structural changes in the brain, especially in the hippocampus. Fixed rat brains were analyzed by ex vivo DTI at 2?h and 42 days after blast (or sham) exposure(s). An anatomy-based region of interest analysis revealed significant interactions in axial and radial diffusivity in a number of subcortical structures at 2?h only. Differences between single- and multiple-injured rats were largely in the thalamus but not the hippocampus. Our findings demonstrate the value and the limitations of DTI in providing a better understanding of mbTBI pathobiology. PMID:24786839

  9. Influence of ambient air pressure on the energy conversion of laser-breakdown induced blast waves

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Komurasaki, Kimiya; Arakawa, Yoshihiro

    2013-09-01

    Influence of ambient pressure on energy conversion efficiency from a Nd?:?glass laser pulse (? = 1.053 µm) to a laser-induced blast wave was investigated at reduced pressure. Temporal incident and transmission power histories were measured using sets of energy meters and photodetectors. A half-shadowgraph half-self-emission method was applied to visualize laser absorption waves. Results show that the blast energy conversion efficiency ?bw decreased monotonically with the decrease in ambient pressure. The decrease was small, from 40% to 38%, for the pressure change from 101 kPa to 50 kPa, but the decrease was considerable, to 24%, when the pressure was reduced to 30 kPa. Compared with a TEA-CO2-laser-induced blast wave (? = 10.6 µm), higher fraction absorption in the laser supported detonation regime ?LSD of 90% was observed, which is influenced slightly by the reduction of ambient pressure. The conversion fraction ?bw/?LSD?90% was achieved at pressure >50 kPa, which is significantly higher than that in a CO2 laser case.

  10. Flow of supersonic jets across flat plates: Implications for ground-level flow from volcanic blasts

    NASA Astrophysics Data System (ADS)

    Orescanin, Mara M.; Prisco, David; Austin, Joanna M.; Kieffer, Susan W.

    2014-04-01

    We report on laboratory experiments examining the interaction of a jet from an overpressurized reservoir with a canonical ground surface to simulate lateral blasts at volcanoes such as the 1980 blast at Mount St. Helens. These benchmark experiments test the application of supersonic jet models to simulate the flow of volcanic jets over a lateral topography. The internal shock structure of the free jet is modified such that the Mach disk shock is elevated above the surface. In elevation view, the width of the shock is reduced in comparison with a free jet, while in map view the dimensions are comparable. The distance of the Mach disk shock from the vent is in good agreement with free jet data and can be predicted with existing theory. The internal shock structures can interact with and penetrate the boundary layer. In the shock-boundary layer interaction, an oblique shock foot is present in the schlieren images and a distinctive ground signature is evident in surface measurements. The location of the oblique shock foot and the surface demarcation are closely correlated with the Mach disk shock location during reservoir depletion, and therefore, estimates of a ground signature in a zone devastated by a blast can be based on the calculated shock location from free jet theory. These experiments, combined with scaling arguments, suggest that the imprint of the Mach disk shock on the ground should be within the range of 4-9 km at Mount St. Helens depending on assumed reservoir pressure and vent dimensions.

  11. CORRELATIONS IN THE (SUB)MILLIMETER BACKGROUND FROM ACT Multiplication-Sign BLAST

    SciTech Connect

    Hajian, Amir; Battaglia, Nick; Bond, J. Richard [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada); Viero, Marco P.; Bock, James J. [California Institute of Technology, Pasadena, CA 91125 (United States); Addison, Graeme [Department of Astrophysics, Oxford University, Oxford, OX1 3RH (United Kingdom); Aguirre, Paula [Departamento de Astronomia y Astrofisica, Facultad de Fisica, Pontificia Universidad Catolica, Casilla 306, Santiago 22 (Chile); Appel, John William; Duenner, Rolando; Essinger-Hileman, Thomas; Fowler, Joseph W.; Hincks, Adam D. [Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544 (United States); Das, Sudeep; Dunkley, Joanna [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States); Devlin, Mark J.; Dicker, Simon R. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Hughes, John P. [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854-8019 (United States); Halpern, Mark [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z4 (Canada); Hasselfield, Matthew [Laboratoire APC, Universite Paris Diderot, 75205 Paris (France); Hilton, Matt [Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, University of KwaZulu-Natal, Durban 4041 (South Africa); and others

    2012-01-01

    We present measurements of the auto- and cross-frequency correlation power spectra of the cosmic (sub)millimeter background at 250, 350, and 500 {mu}m (1200, 860, and 600 GHz) from observations made with the Balloon-borne Large Aperture Submillimeter Telescope (BLAST); and at 1380 and 2030 {mu}m (218 and 148 GHz) from observations made with the Atacama Cosmology Telescope (ACT). The overlapping observations cover 8.6 deg{sup 2} in an area relatively free of Galactic dust near the south ecliptic pole. The ACT bands are sensitive to radiation from the cosmic microwave background, to the Sunyaev-Zel'dovich effect from galaxy clusters, and to emission by radio and dusty star-forming galaxies (DSFGs), while the dominant contribution to the BLAST bands is from DSFGs. We confirm and extend the BLAST analysis of clustering with an independent pipeline and also detect correlations between the ACT and BLAST maps at over 25{sigma} significance, which we interpret as a detection of the DSFGs in the ACT maps. In addition to a Poisson component in the cross-frequency power spectra, we detect a clustered signal at 4{sigma}, and using a model for the DSFG evolution and number counts, we successfully fit all of our spectra with a linear clustering model and a bias that depends only on redshift and not on scale. Finally, the data are compared to, and generally agree with, phenomenological models for the DSFG population. This study demonstrates the constraining power of the cross-frequency correlation technique to constrain models for the DSFGs. Similar analyses with more data will impose tight constraints on future models.

  12. Correlations in the (Sub)Mil1imeter Background from ACT x BLAST

    NASA Technical Reports Server (NTRS)

    Hajian, Amir; Battaglia,Nick; Bock, James J.; Bond, J. Richard; Nolta, Michael R.; Sievers, Jon; Wollack, Ed

    2011-01-01

    We present measurements of the auto- and cross-frequency correlation power spectra of the cosmic (sub)millimeter background at: 250, 350, and 500 microns (1200, 860, and 600 GHz) from observations made with the Balloon-borne Large Aperture Submillimeter Telescope, BLAST; and at 1380 and 2030 microns (218 and 148 GHz) from observations made with the Atacama Cosmology Telescope, ACT. The overlapping observations cover 8.6 deg(sup 2) in an area relatively free of Galactic dust near the south ecliptic pole (SEP). The ACT bands are sensitive to radiation from the CMB, the Sunyaev-Zel'dovich (SZ) effect from galaxy clusters, and to emission by radio and dusty star-forming galaxies (DSFGs), while the dominant contribution to the BLAST bands is from DSFGs. We confirm and extend the BLAST analysis of clustering with an independent pipeline, and also detect correlations between the ACT and BLAST maps at over 25(sigma) significance, which we interpret as a detection of the DSFGs in the ACT maps. In addition to a Poisson component in the cross-frequency power spectra, we detect a clustered signal at 4(sigma), and using a model for the DSFG evolution and number counts, we successfully fit all our spectra with a linear clustering model and a bias that depends only on red shift and not on scale. Finally, the data are compared to, and generally agree with, phenomenological models for the DSFG population. This study represents a first of its kind, and demonstrates the constraining power of the cross-frequency correlation technique to constrain models for the DSFGs. Similar analyses with more data will impose tight constraints 011 future models.

  13. Search for Resonance Phenomena in SILICON28 + SILICON28 Reactions

    Microsoft Academic Search

    Stephanie Beth Dicenzo

    1980-01-01

    ('28)Si + ('28)Si reactions have been studied in a search for resonance phenomena similar to those observed in reactions involving lighter nuclei, especially lighter alpha-particle nuclei. Charged particle detection of the evaporation residues at a fixed laboratory angle provides weak evidence for the existence of small (2%) structures in the fusion excitation function. Measurements of the characteristic gamma rays of

  14. Single heartbeat cardiac tagging for the evaluation of transient phenomena

    Microsoft Academic Search

    Daniel A. Herzka; J. Andrew Derbyshire; Peter Kellman; Elliot R. McVeigh

    2005-01-01

    Many cardiac abnormalities are of a transient nature, creating a beat-to-beat variation in myocardial function. This work pre- sents the cardiac imaging technique for the measurement of regional function during transient cardiac phenomena. All infor- mation necessary for the reconstruction of a cine loop is ac- quired within a single heartbeat, avoiding the temporal blurring introduced by segmented imaging due

  15. 48 Optical Illusions & Visual Phenomena

    NSDL National Science Digital Library

    Have you ever wondered how different optical illusions work? This fun, informative, and very cool website developed by ophthalmologist Dr. Michael Bach of the University of Freiburg's Medical School introduces 48 interactive visual illusions and phenomena. The illusions are animated and accompanied by explanations that help visitors make sense of their perceptual responses. Major illusion categories include: Motion & Time, Luminance & Contrast, Colour, Cognitive, and more. The site is still in progress, and Dr. Bach encourages both general feedback, and additional scientific information for improving the illusion explanations. The second site, also from Professor Bach, presents site users with an interactive, online Visual Acuity Test. Note: The Contrast component of the Test has yet to be implemented.

  16. The quest for new phenomena

    SciTech Connect

    Hinchliffe, I.

    1996-12-01

    The Standard Model of particle physics has been very successful in describing experimental data with great precision. With the exception of some neutrino anomalies, there is no data that is in disagreement with it. Nevertheless, the model is regarded as incomplete and unsatisfactory. There is no explanation of the pattern of quark and lepton masses and, possibly more important, no understanding of the scale of electroweak interactions. Electroweak symmetry breaking is implemented in the Standard Model from the presence of a scalar electroweak doublet, the Higgs field, that acquires a vacuum expectation value of order 250 GeV and leaves as a remnant one physical state, the electrically neutral Higgs boson whose mass is not predicted. In this talk, the author compares the techniques used at, and capabilities of, various facilities in searching for new phenomena. The author emphasizes the cases where information from more than one facility may be needed to fully explore the physics.

  17. Relaxation phenomena in cryogenic electrolytes

    NASA Astrophysics Data System (ADS)

    Shikin, V.; Chikina, I.; Nazin, S.

    2013-06-01

    Proposed is a scenario for the development of observed relaxation phenomena in a cryogenic electrolyte with the structure of "liquid hydrogen + injected ions." Ions of one sign are generated in the bulk of liquid hydrogen in the presence of external field E? by a stationary radioactive source of ± ions at the bottom of a vessel. After accumulation near the free surface of the liquid with a finite density ns the ions can break its stability producing a pulse of ion current to the collector located above the liquid surface. The outlined process is periodically repeated. Its period contains information on the ion mobility and, which is most interesting, on dissociation (association) processes occurring in a system of charged particles placed in an external field. The cryogenic problem is a good model for dissociation in the presence of external field occurring in normal electrolytes without any external ion sources.

  18. Unidentified phenomena - Unusual plasma behavior?

    NASA Astrophysics Data System (ADS)

    Avakian, S. V.; Kovalenok, V. V.

    1992-06-01

    The paper describes observations of a phenomenon belonging to the UFO category and the possible causes of these events. Special attention is given to an event which occurred during the night of September 19-20, 1974, when a huge 'star' was observed over Pertrozavodsk (Russia), consisting of a bright-white luminous center, emitting beams of light, and a less bright light-blue shell. The star gradually formed a cometlike object with a tail consisting of beams of light and started to descend. It is suggested that this event was related to cosmic disturbances caused by an occurrence of unusually strong solar flares. Other examples are presented that relate unusual phenomena observed in space to the occurrence of strong magnetic turbulence events.

  19. Emergent Phenomena at Oxide Interfaces

    SciTech Connect

    Hwang, H.Y.

    2012-02-16

    Transition metal oxides (TMOs) are an ideal arena for the study of electronic correlations because the s-electrons of the transition metal ions are removed and transferred to oxygen ions, and hence the strongly correlated d-electrons determine their physical properties such as electrical transport, magnetism, optical response, thermal conductivity, and superconductivity. These electron correlations prohibit the double occupancy of metal sites and induce a local entanglement of charge, spin, and orbital degrees of freedom. This gives rise to a variety of phenomena, e.g., Mott insulators, various charge/spin/orbital orderings, metal-insulator transitions, multiferroics, and superconductivity. In recent years, there has been a burst of activity to manipulate these phenomena, as well as create new ones, using oxide heterostructures. Most fundamental to understanding the physical properties of TMOs is the concept of symmetry of the order parameter. As Landau recognized, the essence of phase transitions is the change of the symmetry. For example, ferromagnetic ordering breaks the rotational symmetry in spin space, i.e., the ordered phase has lower symmetry than the Hamiltonian of the system. There are three most important symmetries to be considered here. (i) Spatial inversion (I), defined as r {yields} -r. In the case of an insulator, breaking this symmetry can lead to spontaneous electric polarization, i.e. ferroelectricity, or pyroelectricity once the point group belongs to polar group symmetry. (ii) Time-reversal symmetry (T) defined as t {yields} -t. In quantum mechanics, the time-evolution of the wave-function {Psi} is given by the phase factor e{sup -iEt/{h_bar}} with E being the energy, and hence time-reversal basically corresponds to taking the complex conjugate of the wave-function. Also the spin, which is induced by the 'spinning' of the particle, is reversed by time-reversal. Broken T-symmetry is most naturally associated with magnetism, since the spin operator changes sign with T-operation. (iii) Gauge symmetry (G), which is associated with a change in the phase of the wave-function as {Psi} {yields} e{sup i{theta}}{Psi}. Gauge symmetry is connected to the law of charge conservation, and broken G-symmetry corresponds to superconductivity/superfluidity. To summarize, the interplay among these electronic degrees of freedom produces various forms of symmetry breaking patterns of I, T, and G, leading to novel emergent phenomena, which can appear only by the collective behavior of electrons and cannot be expected from individual electrons. Figure 1 shows this schematically by means of several representative phenomena. From this viewpoint, the interfaces of TMOs offer a unique and important laboratory because I is already broken by the structure itself, and the detailed form of broken I-symmetry can often be designed. Also, two-dimensionality usually enhances the effects of electron correlations by reducing their kinetic energy. These two features of oxide interfaces produce many novel effects and functions that cannot be attained in bulk form. Given that the electromagnetic responses are a major source of the physical properties of solids, and new gauge structures often appear in correlated electronic systems, we put 'emergent electromagnetism' at the center of Fig. 1.

  20. Nanoscale Phenomena in Oxide Heterostructures

    NASA Astrophysics Data System (ADS)

    Sulpizio, Joseph A.; Ilani, Shahal; Irvin, Patrick; Levy, Jeremy

    2014-07-01

    Recent advances in creating complex oxide heterostructures, interfaces formed between two different transition-metal oxides, have heralded a new era of materials and physics research, enabling a uniquely diverse set of coexisting physical properties to be combined with an ever-increasing degree of experimental control. These systems have exhibited varied phenomena such as superconductivity, magnetism, and ferroelasticity, all of which are gate tunable, demonstrating their promise for fundamental discovery and technological innovation. To fully exploit this richness, it is necessary to understand and control the physics on the smallest scales, making the use of nanoscale probes essential. Using the prototypical LaAlO3/SrTiO3 interface as a guide, we explore the exciting developments in the physics of oxide-based heterostructures, with a focus on nanostructures and the nanoscale probes employed to unravel their complex behavior.

  1. Critical Phenomena in Liquid-Liquid Mixtures

    NASA Astrophysics Data System (ADS)

    Jacobs, D. T.

    2000-04-01

    Critical phenomena provide intriguing and essential insight into many issues in condensed matter physics because of the many length scales involved. Large density or concentration fluctuations near a system's critical point effectively mask the identity of the system and produce universal phenomena that have been well studied in simple liquid-vapor and liquid-liquid systems. Such systems have provided useful model systems to test theoretical predictions which can then be extended to more complicated systems. Along various thermodynamic paths, several quantities exhibit a simple power-law dependence close to the critical point. The critical exponents describing these relationships are universal and should depend only on a universality class determined by the order-parameter and spatial dimensionality of the system. Liquid gas, binary fluid mixtures, uniaxial ferromagnetism, polymer-solvent, and protein solutions all belong to the same (Ising model) universality class. The diversity of critical systems that can be described by universal relations indicates that experimental measurements on one system should yield the same information as on another. Our experimental investigations have tested existing theory and also extended universal behavior into new areas. By measuring the coexistence curve, heat capacity, thermal expansion and static light scattering (turbidity) in various liquid-liquid and polymer-solvent systems, we have determined critical exponents and amplitudes that have sometimes confirmed and other times challenged current theory. Recent experiments investigating the heat capacity and light scattering in a liquid-liquid mixture very close to the critical point will be discussed. This research is currently supported by The Petroleum Research Fund and by NASA grant NAG8-1433 with some student support from NSF-DMR 9619406.

  2. 8.6: Presentation session: BRAiN measurement and imaging technologies, brain injuries and neuro-regeneration panel, and making a difference: Identifying and closing the knowledge gaps discussion\\/forum: “Animal models for the study of military-related, blast-induced traumatic brain injury”

    Microsoft Academic Search

    Joseph McCabe

    2010-01-01

    In present war time conditions, traumatic brain injury (TBI) has moved to the forefront as a “signature injury.” In terms of prevalence and understanding the biological mechanisms that underlie the injury, blast-induced TBI -particularly in “mild” cases-has proven to be a significant challenge for military medicine. Basic research that employs animal models of TBI is a key element for furthering

  3. PREFACE Integrability and nonlinear phenomena Integrability and nonlinear phenomena

    NASA Astrophysics Data System (ADS)

    Gómez-Ullate, David; Lombardo, Sara; Mañas, Manuel; Mazzocco, Marta; Nijhoff, Frank; Sommacal, Matteo

    2010-10-01

    Back in 1967, Clifford Gardner, John Greene, Martin Kruskal and Robert Miura published a seminal paper in Physical Review Letters which was to become a cornerstone in the theory of integrable systems. In 2006, the authors of this paper received the AMS Steele Prize. In this award the AMS pointed out that `In applications of mathematics, solitons and their descendants (kinks, anti-kinks, instantons, and breathers) have entered and changed such diverse fields as nonlinear optics, plasma physics, and ocean, atmospheric, and planetary sciences. Nonlinearity has undergone a revolution: from a nuisance to be eliminated, to a new tool to be exploited.' From this discovery the modern theory of integrability bloomed, leading scientists to a deep understanding of many nonlinear phenomena which is by no means reachable by perturbation methods or other previous tools from linear theories. Nonlinear phenomena appear everywhere in nature, their description and understanding is therefore of great interest both from the theoretical and applicative point of view. If a nonlinear phenomenon can be represented by an integrable system then we have at our disposal a variety of tools to achieve a better mathematical description of the phenomenon. This special issue is largely dedicated to investigations of nonlinear phenomena which are related to the concept of integrability, either involving integrable systems themselves or because they use techniques from the theory of integrability. The idea of this special issue originated during the 18th edition of the Nonlinear Evolution Equations and Dynamical Systems (NEEDS) workshop, held at Isola Rossa, Sardinia, Italy, 16-23 May 2009 (http://needs-conferences.net/2009/). The issue benefits from the occasion offered by the meeting, in particular by its mini-workshops programme, and contains invited review papers and contributed papers. It is worth pointing out that there was an open call for papers and all contributions were peer reviewed according to the standards of the journal. The selection of papers in this issue aims to bring together recent developments and findings, even though it consists of only a fraction of the impressive developments in recent years which have affected a broad range of fields, including the theory of special functions, quantum integrable systems, numerical analysis, cellular automata, representations of quantum groups, symmetries of difference equations, discrete geometry, among others. The special issue begins with four review papers: Integrable models in nonlinear optics and soliton solutions Degasperis [1] reviews integrable models in nonlinear optics. He presents a number of approximate models which are integrable and illustrates the links between the mathematical and applicative aspects of the theory of integrable dynamical systems. In particular he discusses the recent impact of boomeronic-type wave equations on applications arising in the context of the resonant interaction of three waves. Hamiltonian PDEs: deformations, integrability, solutions Dubrovin [2] presents classification results for systems of nonlinear Hamiltonian partial differential equations (PDEs) in one spatial dimension. In particular he uses a perturbative approach to the theory of integrability of these systems and discusses their solutions. He conjectures universality of the critical behaviour for the solutions, where the notion of universality refers to asymptotic independence of the structure of solutions (at the point of gradient catastrophe) from the choice of generic initial data as well as from the choice of a generic PDE. KP solitons in shallow water Kodama [3] presents a survey of recent studies on soliton solutions of the Kadomtsev-Petviashvili (KP) equation. A large variety of exact soliton solutions of the KP equation are presented and classified. The study includes numerical analysis of the stability of the found solution as well as numerical simulations of the initial value problems which indicate that a certain class of initial waves approach asymptotically these exact solutions

  4. Blast mitigation capabilities of aqueous foam.

    SciTech Connect

    Hartman, William Franklin; Larsen, Marvin Elwood; Boughton, Bruce A.

    2006-02-01

    A series of tests involving detonation of high explosive blanketed by aqueous foam (conducted from 1982 to 1984) are described in primarily terms of recorded peak pressure, positive phase specific impulse, and time of arrival. The investigation showed that optimal blast mitigation occurs for foams with an expansion ratio of about 60:1. Simple analyses representing the foam as a shocked single phase mixture are presented and shown inadequate. The experimental data demonstrate that foam slows down and broadens the propagated pressure disturbance relative to a shock in air. Shaped charges and flyer plates were evaluated for operation in foam and appreciable degradation was observed for the flyer plates due to drag created by the foam.

  5. Mercury in dumped blast furnace sludge

    NASA Astrophysics Data System (ADS)

    Földi, Corinna

    2014-05-01

    Blast furnace sludge (BFS) is a waste generated in the production of pig iron and was dumped in sedimentation ponds. As these wastes often contain high contents of zinc, lead, cadmium, and arsenic, significant hazards to environmental surroundings may arise from former BFS sedimentation ponds. Sixty-five samples from seven BFS locations in Europe were investigated regarding the toxic element mercury (Hg) for the first time. The charge material of the blast furnace operations (coke, iron ores, and additives such as olivine, bauxite, ilmenite and gravels) revealed Hg contents from 0.015 to 0.093 mg kg-1. In comparison, the Hg content of BFS varied between 0.006 and 20.8 mg kg-1 with a median of 1.63 mg kg-1, which indicates enrichment with Hg. For one site with a larger sample set (n = 31), Hg showed a stronger correlation with the total non-calcareous carbon (C) including coke and graphite (r = 0.695; n = 31; p < 0.001). It can be assumed that these C-rich compounds are hosting phases for Hg. The solubility of Hg was rather low and did not exceed 0.43% of total Hg. The correlation between the total Hg concentration and total amount of NH4NO3-soluble Hg was relatively poor (r = 0.496; n = 27; p = 0.008) indicating varying hazard potentials of the different BFS. Consequently, BFS is a mercury-containing waste and dumped BFS should be regarded as potentially mercury-contaminated sites.

  6. DETAIL VIEW OF THE #2 BLAST FURNACE AND SKIP HOIST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF THE #2 BLAST FURNACE AND SKIP HOIST. DUST CATCHER IS AT THE RIGHT. VIEW IS FROM THE EAST. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  7. 32. VIEW OF DEMOLISHED FOUNDRY SAND BLASTING AND CLEANING BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. VIEW OF DEMOLISHED FOUNDRY SAND BLASTING AND CLEANING BUILDING AFTER DUST HAS SETTLED. - Baltimore & Ohio Railroad, Mount Clare Shops, South side of Pratt Street between Carey & Poppleton Streets, Baltimore, Independent City, MD

  8. Investigation of ultrafast laser-driven radiative blast waves.

    PubMed

    Edwards, M J; MacKinnon, A J; Zweiback, J; Shigemori, K; Ryutov, D; Rubenchik, A M; Keilty, K A; Liang, E; Remington, B A; Ditmire, T

    2001-08-20

    We have examined the evolution of cylindrically symmetric blast waves produced by the deposition of femtosecond laser pulses in gas jets. In high- Z gases radiative effects become important. We observe the production of an ionization precursor ahead of the shock front and deceleration parameters below the adiabatic value of 1/2 (for a cylinder), an effect expected when the blast wave loses energy by radiative cooling. Despite significant radiative cooling, the blast waves do not appear to develop thin shell instabilities expected for strongly radiative waves. This is believed to be due to the stabilizing effect of a relatively thick blast wave shell resulting in part from electron thermal conduction effects. PMID:11497951

  9. 6. OUTER BLAST DOOR, WEST REAR. Edwards Air Force ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. OUTER BLAST DOOR, WEST REAR. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  10. Modelling ironmaking blast furnace: Solid flow and thermochemical behaviours

    NASA Astrophysics Data System (ADS)

    Shen, Yansong; Guo, Baoyu; Yu, Aibing; Chew, Sheng; Austin, Peter

    2013-06-01

    Ironmaking blast furnace is a counter-, co-, cross-current moving bed reactor, where solid particles are charged at the furnace top forming a downward moving bed while gas are introduced at the lower part of furnace and travels upward through the solid bed of varying porosity, reducing solid ore to liquid iron at the cohesive zone. These three phases interact intensely. In this paper, a three-dimensional mathematical model is developed. The model describes the motion of solid and gas, based on continuum approach, and implements the so-called force balance model for the liquid flow. The model is applied to a blast furnace, where raceway cavity is considered explicitly. The results demonstrate and characterize the key multiphase flow patterns of solid-gas-liquid at different regions inside the blast furnace, in particular solid flow and associated thermochemical behaviours of solid particles. This model offers a costeffective tool to understand and optimize blast furnace operation.

  11. Analysis of blast mitigation strategies exploiting fluid-structure interaction

    E-print Network

    Kambouchev, Nayden Dimitrov, 1980-

    2007-01-01

    Blast attacks have become the most pervasive threat in both civil and military contexts. However, there is currently a limited understanding of the mechanisms of loading, damage and failure of structures, and injury to ...

  12. BICARBONATE OF SODA BLASTING TECHNOLOGY FOR AIRCRAFT WHEEL PAINTING

    EPA Science Inventory

    This evaluation addressed product quality, waste reduction/pollution prevention and economics in replacing chemical solvent strippers with a bicarbonate of soda blasting technology for removal of paint from aircraft wheels. The evaluation was conducted in the Paint Stripping Sho...

  13. BICARBONATE OF SODA BLASTING TECHNOLOGY FOR AIRCRAFT WHEEL DEPAINTING

    EPA Science Inventory

    This evaluation addressed product quality, waste reduction/pollution prevention and economics in replacing chemical solvent strippers with a bicarbonate of soda blasting technology for removal of point from aircraft wheels. he evaluation was conducted in the Paint Stripping Shop ...

  14. Blast TBI Models, Neuropathology, and Implications for Seizure Risk

    PubMed Central

    Kovacs, S. Krisztian; Leonessa, Fabio; Ling, Geoffrey S. F.

    2014-01-01

    Traumatic brain injury (TBI) due to explosive blast exposure is a leading combat casualty. It is also implicated as a key contributor to war related mental health diseases. A clinically important consequence of all types of TBI is a high risk for development of seizures and epilepsy. Seizures have been reported in patients who have suffered blast injuries in the Global War on Terror but the exact prevalence is unknown. The occurrence of seizures supports the contention that explosive blast leads to both cellular and structural brain pathology. Unfortunately, the exact mechanism by which explosions cause brain injury is unclear, which complicates development of meaningful therapies and mitigation strategies. To help improve understanding, detailed neuropathological analysis is needed. For this, histopathological techniques are extremely valuable and indispensable. In the following we will review the pathological results, including those from immunohistochemical and special staining approaches, from recent preclinical explosive blast studies. PMID:24782820

  15. 14. Inner double blast door entrance to perimeter acquisition radar ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Inner double blast door entrance to perimeter acquisition radar building security area - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Building, Limited Access Area, between Limited Access Patrol Road & Service Road A, Nekoma, Cavalier County, ND

  16. Blast injury with particular reference to recent terrorist bombing incidents.

    PubMed Central

    Hill, J. F.

    1979-01-01

    The aetiology of primary blast lung is discussed with reference to the biodynamics of blast injury, and the clinical and pathological features of the condition are described. An analysis of casualties from bomb blast incidents occurring in Northern Ireland leads to the following conclusions concerning the injuries found in persons exposed to explosions: (1) there is a predominance of head and neck trauma, including fractures, lacerations, burns, and eye and ear injuries; (2) fractures and traumatic amputations are common and often multiple; (3) penetrating trunk wounds carry a grave prognosis; and (4) primary blast lung is rare. A comparison of four bombing incidents in England in 1973 and 1974 shows how the type and severity of injury are related to the place in which the explosion occurs. The administrative and clinical aspects of the management of casualties resulting from terrorist bombing activities are discussed. PMID:369445

  17. 30 CFR 56.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  18. 30 CFR 57.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  19. 30 CFR 56.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  20. 30 CFR 57.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  1. 30 CFR 57.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  2. 30 CFR 56.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  3. 30 CFR 57.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  4. 30 CFR 56.6306 - Loading, blasting, and security.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of...

  5. 30 CFR 77.1304 - Blasting agents; special provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...of the potential hazard of static electricity shall be made. Adequate...to eliminate the hazard of static electricity before blasting agent use is...to permit the dissipation of static electricity and high enough to limit...

  6. 30 CFR 77.1304 - Blasting agents; special provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...of the potential hazard of static electricity shall be made. Adequate...to eliminate the hazard of static electricity before blasting agent use is...to permit the dissipation of static electricity and high enough to limit...

  7. 30 CFR 77.1304 - Blasting agents; special provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...of the potential hazard of static electricity shall be made. Adequate...to eliminate the hazard of static electricity before blasting agent use is...to permit the dissipation of static electricity and high enough to limit...

  8. 30 CFR 77.1304 - Blasting agents; special provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...of the potential hazard of static electricity shall be made. Adequate...to eliminate the hazard of static electricity before blasting agent use is...to permit the dissipation of static electricity and high enough to limit...

  9. 30 CFR 77.1304 - Blasting agents; special provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...of the potential hazard of static electricity shall be made. Adequate...to eliminate the hazard of static electricity before blasting agent use is...to permit the dissipation of static electricity and high enough to limit...

  10. 24. GENERAL VIEW OF NEW CONCRETE BLAST BERM FOR NEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. GENERAL VIEW OF NEW CONCRETE BLAST BERM FOR NEW LIQUID HYDROGEN TANK FARM; VIEW TO EAST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28402, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  11. Numerical solutions for unsteady laminar boundary layers behind blast waves

    NASA Astrophysics Data System (ADS)

    Liu, S. W.; Mirels, H.

    1980-04-01

    The paper presents the similarity solutions obtained for laminar boundary layers behind a power-law shock associated with a blast wave. A finite-difference method based on Blottner's numerical scheme (1970) is used. The results are valid, at all times, in the entire flow region between the shock front and the immediate vicinity of the blast-wave origin provided the boundary layer remains laminar.

  12. Visualization of blast waves created by exploding bridge wires

    Microsoft Academic Search

    M. J. Murphy; R. J. Adrian; D. S. Stewart; G. S. Elliott; K. A. Thomas; J. E. Kennedy

    2005-01-01

    Blast waves created by small exploding bridge wires are used as a test bed for the development of a particle image velocimetry\\u000a (PIV) technique that uses polymers, seeded with scattering particles, as dynamic witness plates. Combined with pulsed, incoherent\\u000a schlieren photography, the PIV method permits visualization of the instantaneous velocity vector field in a plane cutting\\u000a through the blast wave.

  13. Blast trauma: the fourth weapon of mass destruction.

    PubMed

    Born, C T

    2005-01-01

    Injury from blast is becoming more common in the non-military population. This is primarily a result of an increase in politically motivated bombings within the civilian sector. Explosions unrelated to terrorism may also occur in the industrial setting. Civilian physicians and surgeons need to have an understanding of the pathomechanics and physiology of blast injury and to recognize the hallmarks of severity in order to increase survivorship. Because victims may be transported rapidly to the hospital, occult injury to gas and fluid containing organs (particularly the ears, bowel and lungs) may go unrecognized. Information surrounding the physical environment of the explosion (whether inside or outside, underwater, associated building collapse, etc) will prove useful. Most of the immediate deaths are caused by primary blast injury from the primary blast wave, but secondary blast injury from flying debris can also be lethal and involve a much wider radius. Liberal use of X-ray examination in areas of skin punctures will help to identify a need for exploration and/or foreign body removal. Biologic serum markers may have a role in identifying victims of primary blast injury and assist in monitoring their clinical progress. Tertiary blast injury results from the airborne propulsion of the victim by the shockwave and is a source of additional blunt head and torso trauma as well as fractures. Miscellaneous (quaternary) blast injury include thermal or dust inhalation exposure as well as crush and compartment syndromes from building collapse. Any explosion has the potential to be associated with nuclear, biologic or chemical contaminants, and this should remain a consideration for healthcare givers until proven otherwise. PMID:16425623

  14. Engineering model for predicting rubble motion during blasting

    SciTech Connect

    Schamaun, J.T.

    1982-12-01

    Recent applications of explosives and blasting agents to rubble rock have led to requirements for more elaborate design and analysis methods. In most blasting uses, it is necessary not only to fracture the rock, but also to move the broken rubble in a predictable manner. Many in-situ extraction techniques require rubblization to take place in a confined region where rock motion is a predominate factor in creating a permeable broken bed. In this paper, an engineering model is presented which describes the large rubble motion during blasting. This model is intended to provide the blast designer with a tool for evaluation and further refinement of blasting patterns and timing sequences. In this model the rock medium is represented by a discrete series of circular regions of fractured material. These regions are set in motion by pressure loads from the explosive. The motion of the regions is calculated using a step-wise, explicit, numerical time integration method. Interaction of adjacent regions is based on inelastic impact of spherical bodies. The derivation of this model is presented along with the background for selecting loading pressure based on explosive behavior. Three typical examples, including both cratering and bench geometries, are discussed which illustrate the use of this model to predict rubble motion. This engineering representation appears to provide a practical model for use in predicting rubble motion and a tool for design evaluation of blasting in confined geometries. 15 figures.

  15. Engineering model for predicting rubble motion during blasting

    SciTech Connect

    Schamaun, J.T.

    1983-01-01

    Recent applications of explosives and blasting agents to rubble rock have led to requirements for more elaborate design and analysis methods. In most blasting uses, it is necessary not only to fracture the rock, but also to move the broken rubble in a predictable manner. Many in situ extraction techniques require rubblization to take place in a confined region where rock motion is a predominate factor in creating a permeable broken bed. In this paper, an engineering model is presented which describes the large rubble motion during blasting. This model is intended to provide the blast designer with a tool for evaluation and further refinement of blasting patterns and timing sequences. In this model the rock medium is represented by a discrete series of circular regions of fractured material. These regions are set in motion by pressure loads from the explosive. The motion of the regions is calculated using a step-wise, explicit, numerical time integration method. Interaction of adjacent regions is based on inelastic impact of spherical bodies. The derivation of this model is presented along with the background for selecting loading pressure based on explosive behavior. Three typical examples, including both cratering and bench geometries, are discussed which illustrate the use of this model to predict rubble motion. This engineering representation appears to provide a practical model for use in predicting rubble motion and a tool for design evaluation of blasting in confined geometries. 15 figures, 1 table.

  16. Patient with sleeping disorder: While using nucleotide BLAST, make sure that you choose blastn: the default is MegaBlast

    E-print Network

    Utrecht, Universiteit

    CP2 Patient with sleeping disorder: While using nucleotide BLAST on SNPs causing sleep-disorders. Function Prediction: BLASTp search the same function. To identify the chromosome, one should perform tblastn against

  17. Data acquisition and simulation of natural phenomena

    Microsoft Academic Search

    QinPing Zhao

    2011-01-01

    Virtual natural phenomena obtained through mathematical-physical modeling and simulation as well as graphics emulation can\\u000a meet the user’s requirements for sensory experiences to a certain extent but they can hardly have the same accurate physical\\u000a consistency as real natural phenomena. The technology for data acquisition and natural phenomena simulation can enable us\\u000a to obtain multi-dimensional and multi-modal data directly from

  18. Intrinsic interfacial phenomena in manganite heterostructures

    NASA Astrophysics Data System (ADS)

    Vaz, C. A. F.; Walker, F. J.; Ahn, C. H.; Ismail-Beigi, S.

    2015-04-01

    We review recent advances in our understanding of interfacial phenomena that emerge when dissimilar materials are brought together at atomically sharp and coherent interfaces. In particular, we focus on phenomena that are intrinsic to the interface and review recent work carried out on perovskite manganites interfaces, a class of complex oxides whose rich electronic properties have proven to be a useful playground for the discovery and prediction of novel phenomena.

  19. Intrinsic interfacial phenomena in manganite heterostructures.

    PubMed

    Vaz, C A F; Walker, F J; Ahn, C H; Ismail-Beigi, S

    2015-04-01

    We review recent advances in our understanding of interfacial phenomena that emerge when dissimilar materials are brought together at atomically sharp and coherent interfaces. In particular, we focus on phenomena that are intrinsic to the interface and review recent work carried out on perovskite manganites interfaces, a class of complex oxides whose rich electronic properties have proven to be a useful playground for the discovery and prediction of novel phenomena. PMID:25721578

  20. Symptom Complaints Following Reports of Blast Versus Non-Blast Mild TBI: Does Mechanism of Injury Matter?

    Microsoft Academic Search

    Heather G. Belanger; Zoe Proctor-Weber; Tracy Kretzmer; Michelle Kim; Louis M. French; Rodney D. Vanderploeg

    2011-01-01

    Patients with a reported history of mild traumatic brain injury (mild TBI) due to blast (n?=?298) or non-blast (n?=?92) mechanisms were asked to complete the Neurobehavioral Symptom Inventory (NSI) and the Post-traumatic Stress Disorder Checklist (PCL). Mechanism of injury did not account for a significant amount of variance in post-concussion symptom reporting overall, nor did severity of mild TBI (i.e.,

  1. Observation of Celestial Phenomena in Ancient China

    NASA Astrophysics Data System (ADS)

    Sun, Xiaochun

    Because of the need for calendar-making and portent astrology, the Chinese were diligent and meticulous observers of celestial phenomena. China has maintained the longest continuous historical records of celestial phenomena in the world. Extraordinary or abnormal celestial events were particularly noted because of their astrological significance. The historical records cover various types of celestial phenomena, which include solar and lunar eclipses, sunspots, "guest stars" (novae or supernovae as we understand today), comets and meteors, and all kinds of planetary phenomena. These records provide valuable historical data for astronomical studies today.

  2. Macroscopic Modeling of Transport Phenomena in

    E-print Network

    Berning, Torsten

    Technology Pontoppidanstræde 101 9220 Aalborg Denmark #12;Title: Macroscopic Modeling of Transport Phenomena applica- tions. This type of fuel cell directly generates electricity from a fuel mixture consisting

  3. Possible relationships between solar activity and meteorological phenomena

    NASA Technical Reports Server (NTRS)

    Bandeen, W. R. (editor); Maran, S. P. (editor)

    1975-01-01

    A symposium was conducted in which the following questions were discussed: (1) the evidence concerning possible relationships between solar activity and meteorological phenomena; (2) plausible physical mechanisms to explain these relationships; and (3) kinds of critical measurements needed to determine the nature of solar/meteorological relationships and/or the mechanisms to explain them, and which of these measurements can be accomplished best from space.

  4. Neuroimaging, Behavioral, and Psychological Sequelae of Repetitive Combined Blast/Impact Mild Traumatic Brain Injury in Iraq and Afghanistan War Veterans

    PubMed Central

    Cross, Donna J.; Yarnykh, Vasily L.; Richards, Todd; Martin, Nathalie M.; Pagulayan, Kathleen; Hoff, David; Hart, Kim; Mayer, Cynthia; Tarabochia, Matthew; Raskind, Murray A.; Minoshima, Satoshi; Peskind, Elaine R.

    2014-01-01

    Abstract Whether persisting cognitive complaints and postconcussive symptoms (PCS) reported by Iraq and Afghanistan war veterans with blast- and/or combined blast/impact-related mild traumatic brain injuries (mTBIs) are associated with enduring structural and/or functional brain abnormalities versus comorbid depression or posttraumatic stress disorder (PTSD) remains unclear. We sought to characterize relationships among these variables in a convenience sample of Iraq and Afghanistan-deployed veterans with (n=34) and without (n=18) a history of one or more combined blast/impact-related mTBIs. Participants underwent magnetic resonance imaging of fractional anisotropy (FA) and macromolecular proton fraction (MPF) to assess brain white matter (WM) integrity; [18F]-fluorodeoxyglucose positron emission tomography imaging of cerebral glucose metabolism (CMRglu); structured clinical assessments of blast exposure, psychiatric diagnoses, and PTSD symptoms; neurologic evaluations; and self-report scales of PCS, combat exposure, depression, sleep quality, and alcohol use. Veterans with versus without blast/impact-mTBIs exhibited reduced FA in the corpus callosum; reduced MPF values in subgyral, longitudinal, and cortical/subcortical WM tracts and gray matter (GM)/WM border regions (with a possible threshold effect beginning at 20 blast-mTBIs); reduced CMRglu in parietal, somatosensory, and visual cortices; and higher scores on measures of PCS, PTSD, combat exposure, depression, sleep disturbance, and alcohol use. Neuroimaging metrics did not differ between participants with versus without PTSD. Iraq and Afghanistan veterans with one or more blast-related mTBIs exhibit abnormalities of brain WM structural integrity and macromolecular organization and CMRglu that are not related to comorbid PTSD. These findings are congruent with recent neuropathological evidence of chronic brain injury in this cohort of veterans. PMID:24102309

  5. Modeling Defect-Induced Phenomena

    NASA Astrophysics Data System (ADS)

    Kuklja, Maija M.; Rashkeev, Sergey N.

    Elucidation of dissociation mechanisms, energy localization, and transfer phenomena in the course of explosive decomposition of energetic materials (EMs) are central for understanding, controlling, and enhancing the performance of these materials as fuels, propellants, and explosives. Quality of energetic materials is often judged using two main parameters: sensitivity to detonation and its performance. Low sensitivity is desired to make the material relatively stable to external stimuli, i.e., controllable and able of triggering rapid dissociation only when needed and not accidentally. Performance, on the other hand, is to be high to provide larger heat of the explosive reaction. These parameters do not necessarily correlate with each other and depend on many variables such as molecular and crystalline structures, history of samples, the particle size, crystal hardness and orientation, external stimuli, aging, storage conditions, and others. Mechanisms governing performance are fairly well understood whereas mechanisms of sensitivity are poorly known and need to be much more extensively studied. It is widely accepted though that the thermal decomposition reactions of the materials play a significant role in their sensitivity to mechanical stimuli and their explosive properties [1].

  6. Precursor films in wetting phenomena.

    PubMed

    Popescu, M N; Oshanin, G; Dietrich, S; Cazabat, A-M

    2012-06-20

    The spontaneous spreading of non-volatile liquid droplets on solid substrates poses a classic problem in the context of wetting phenomena. It is well known that the spreading of a macroscopic droplet is in many cases accompanied by a thin film of macroscopic lateral extent, the so-called precursor film, which emanates from the three-phase contact line region and spreads ahead of the latter with a much higher speed. Such films have been usually associated with liquid-on-solid systems, but in the last decade similar films have been reported to occur in solid-on-solid systems. While the situations in which the thickness of such films is of mesoscopic size are fairly well understood, an intriguing and yet to be fully understood aspect is the spreading of microscopic, i.e. molecularly thin, films. Here we review the available experimental observations of such films in various liquid-on-solid and solid-on-solid systems, as well as the corresponding theoretical models and studies aimed at understanding their formation and spreading dynamics. Recent developments and perspectives for future research are discussed. PMID:22627067

  7. Precursor films in wetting phenomena

    NASA Astrophysics Data System (ADS)

    Popescu, M. N.; Oshanin, G.; Dietrich, S.; Cazabat, A.-M.

    2012-06-01

    The spontaneous spreading of non-volatile liquid droplets on solid substrates poses a classic problem in the context of wetting phenomena. It is well known that the spreading of a macroscopic droplet is in many cases accompanied by a thin film of macroscopic lateral extent, the so-called precursor film, which emanates from the three-phase contact line region and spreads ahead of the latter with a much higher speed. Such films have been usually associated with liquid-on-solid systems, but in the last decade similar films have been reported to occur in solid-on-solid systems. While the situations in which the thickness of such films is of mesoscopic size are fairly well understood, an intriguing and yet to be fully understood aspect is the spreading of microscopic, i.e. molecularly thin, films. Here we review the available experimental observations of such films in various liquid-on-solid and solid-on-solid systems, as well as the corresponding theoretical models and studies aimed at understanding their formation and spreading dynamics. Recent developments and perspectives for future research are discussed.

  8. WESF natural phenomena hazards survey

    SciTech Connect

    Wagenblast, G.R., Westinghouse Hanford

    1996-07-01

    A team of engineers conducted a systematic natural hazards phenomena (NPH) survey for the 225-B Waste Encapsulation and Storage Facility (WESF). The survey is an assessment of the existing design documentation to serve as the structural design basis for WESF, and the Interim Safety Basis (ISB). The lateral force resisting systems for the 225-B building structures, and the anchorages for the WESF safety related systems were evaluated. The original seismic and other design analyses were technically reviewed. Engineering judgment assessments were made of the probability of NPH survival, including seismic, for the 225-B structures and WESF safety systems. The method for the survey is based on the experience of the investigating engineers,and documented earthquake experience (expected response) data.The survey uses knowledge on NPH performance and engineering experience to determine the WESF strengths for NPH resistance, and uncover possible weak links. The survey, in general, concludes that the 225-B structures and WESF safety systems are designed and constructed commensurate with the current Hanford Site design criteria.

  9. Review - Axial compressor stall phenomena

    NASA Technical Reports Server (NTRS)

    Greitzer, E. M.

    1980-01-01

    Stall in compressors can be associated with the initiation of several types of fluid dynamic instabilities. These instabilities and the different phenomena, surge and rotating stall, which result from them, are discussed in this paper. Assessment is made of the various methods of predicting the onset of compressor and/or compression system instability, such as empirical correlations, linearized stability analyses, and numerical unsteady flow calculation procedures. Factors which affect the compressor stall point, in particular inlet flow distortion, are reviewed, and the techniques which are used to predict the loss in stall margin due to these factors are described. The influence of rotor casing treatment (grooves) on increasing compressor flow range is examined. Compressor and compression system behavior subsequent to the onset of stall is surveyed, with particular reference to the problem of engine recovery from a stalled condition. The distinction between surge and rotating stall is emphasized because of the very different consequences on recoverability. The structure of the compressor flow field during rotating stall is examined, and the prediction of compressor performance in rotating stall, including stall/unstall hysteresis, is described.

  10. Monitoring of Transient Lunar Phenomena

    NASA Astrophysics Data System (ADS)

    Barker, Timothy; Farber, Ryan; Ahrendts, Gary

    2014-06-01

    Transient Lunar Phenomena (TLP’s) are described as short-lived changes in the brightness of areas on the face of the Moon. TLP research is characterized by the inability to substantiate, reproduce, and verify findings. Our current research includes the analysis of lunar images taken with two Santa Barbara Instrument Group (SBIG) ST8-E CCD cameras mounted on two 0.36m Celestron telescopes. On one telescope, we are using a sodium filter, and on the other an H-alpha filter, imaging approximately one-third of the lunar surface. We are focusing on two regions: Hyginus and Ina. Ina is of particular interest because it shows evidence of recent activity (Schultz, P., Staid, M., Pieters, C. Nature, Volume 444, Issue 7116, pp. 184-186, 2006). A total of over 50,000 images have been obtained over approximately 35 nights and visually analyzed to search for changes. As of March, 2014, no evidence of TLPs has been found. We are currently developing a Matlab program to do image analysis to detect TLPs that might not be apparent by visual inspection alone.

  11. Attenuation of pulmonary inflammation after exposure to blast overpressure by N-acetylcysteine amide.

    PubMed

    Chavko, Mikulas; Adeeb, Saleena; Ahlers, Stephen T; McCarron, Richard M

    2009-09-01

    Lung contusion is a common problem from blunt chest trauma caused by mechanical forces and by exposure to blast overpressure, often with fatal consequences. Lung contusion is also a risk factor for the development of pneumonia, severe clinical acute lung injury (ALI), and acute respiratory distress syndrome (ARDS). Infiltrating neutrophils are considered to be central mediators of lung injuries after blunt trauma. Recent studies have demonstrated that antioxidants reduced pulmonary inflammation in different models of lung damage. This study examined the effect of antioxidant N-acetylcysteine amide (NACA) on the progression of lung inflammation after exposure to a moderate level of blast overpressure (140 kPa). Rats were administered with NACA (i.p. 100 mg/kg) or placebo (PBS) 30, 60 min and 24 h after exposure. Nonblasted sham-injected animals served as controls. Neutrophil infiltration measured by myeloperoxidase (MPO) activity in the lung was significantly increased at 2 days after blast and returned to controls at 8 days. This increase corresponded with activation of integrin CD11b mRNA and lung inflammatory chemokine mRNA expression; macrophage inflammatory protein-1 (MIP-1), monocyte chemotactic peptide-1 (MCP-1), and cytokine-induced neutrophil chemoattractant-1 (CINC-1). At 8 days, all inflammatory mediators returned to control levels. In addition, expression of heme oxygenase-1 (HO-1) mRNA increased at 2 days after exposure. No changes were detected in the lung manganase superoxide dismutase (MnSOD) or glutathione reductase (GR) mRNA expression after blast. N-Acetylcysteine amide significantly reduced infiltration of neutrophils and CD11b mRNA activation in lungs, and completely blocked activation of MIP-1, MCP-1 and CINC-1 mRNA. The relatively higher inhibition of chemokine mRNAs compared with reduction in MPO activity and CD11b is in accordance with an antioxidant effect of NACA on reactive oxygen species (ROS) accumulation, rather than by an effect on neutrophil sequestration. The inhibition of HO-1 mRNA activation after blast was likely also related to the drug antioxidant effect. PMID:19174737

  12. Modelling of Transient Phenomena in Gas Discharges

    E-print Network

    Eindhoven, Technische Universiteit

    Modelling of Transient Phenomena in Gas Discharges Wouter Brok #12;Copyright 2005 by W.J.M. Brok Johannes Maria Modelling of transient phenomena in gas discharges / by Woutherus Johannes Maria Brok Subject headings : plasma physics / gas discharges / light sources / Monte Carlo methods / fluid models

  13. Repetitive speech phenomena in Parkinson's disease

    Microsoft Academic Search

    Th Benke; C Hohenstein; W Poewe; B Butterworth

    2000-01-01

    OBJECTIVESRepetitive speech phenomena are morphologically heterogeneous iterations of speech which have been described in several neurological disorders such as vascular dementia, progressive supranuclear palsy, Wilson's disease, and Parkinson's disease, and which are presently only poorly understood. The present, prospective study investigated repetitive speech phenomena in Parkinson's disease to describe their morphology, assess their prevalence, and to establish their relation with

  14. Further shock tunnel studies of scramjet phenomena

    NASA Technical Reports Server (NTRS)

    Morgan, R. G.; Paull, A.; Morris, N. A.; Stalker, R. J.

    1986-01-01

    Scramjet phenomena were studied using the shock tunnel T3 at the Australian National University. Simple two dimensional models were used with a combination of wall and central injectors. Silane as an additive to hydrogen fuel was studied over a range of temperatures and pressures to evaluate its effect as an ignition aid. The film cooling effect of surface injected hydrogen was measured over a wide range of equivalence. Heat transfer measurements without injection were repeated to confirm previous indications of heating rates lower than simple flat plate predictions for laminar boundary layers in equilibrium flow. The previous results were reproduced and the discrepancies are discussed in terms of the model geometry and departures of the flow from equilibrium. In the thrust producing mode, attempts were made to increase specific impulse with wall injection. Some preliminary tests were also performed on shock induced ignition, to investigate the possibility in flight of injecting fuel upstream of the combustion chamber, where it could mix but not burn.

  15. On the Nature of Quantum Phenomena

    E-print Network

    Xiaolei Zhang

    2007-12-28

    It is shown that a coherent understanding of all quantized phenomena, including those governed by unitary evolution equations as well as those related to irreversible quantum measurements, can be achieved in a scenario of successive nonequilibrium phase transitions, with the lowest hierarchy of these phase transitions occurring in a ``resonant cavity'' formed by the entire matter and energy content of the universe. In this formalism, the physical laws themselves are resonantly-selected and ordered in the universe cavity in a hierarchical manner, and the values of fundamental constants are determined through a Generalized Mach's Principle. The existence of a preferred reference frame in this scenario is shown to be consistent with the relational nature of the origin of physical laws. Covariant unitary evolution is shown to connect smoothly with the reduction of wavefunction in the preferred frame during quantum measurement. The superluminal nature of quantum processes in the lowest hierarchy coexists with the universal speed limit obeyed by processes in higher hierarchies. A natural quantum-to-classical transition is also obtained which is stable against the diffusive tendency of the unitary quantum evolution processes. In this formalism a realistic quasi-classical ontology is established for the foundations of quantum mechanics.

  16. Acute post-traumatic stress symptoms and age predict outcome in military blast concussion.

    PubMed

    Mac Donald, Christine L; Adam, Octavian R; Johnson, Ann M; Nelson, Elliot C; Werner, Nicole J; Rivet, Dennis J; Brody, David L

    2015-05-01

    High rates of adverse outcomes have been reported following blast-related concussive traumatic brain injury in US military personnel, but the extent to which such adverse outcomes can be predicted acutely after injury is unknown. We performed a prospective, observational study of US military personnel with blast-related concussive traumatic brain injury (n = 38) and controls (n = 34) enrolled between March and September 2012. Importantly all subjects returned to duty and did not require evacuation. Subjects were evaluated acutely 0-7 days after injury at two sites in Afghanistan and again 6-12 months later in the United States. Acute assessments revealed heightened post-concussive, post-traumatic stress, and depressive symptoms along with worse cognitive performance in subjects with traumatic brain injury. At 6-12 months follow-up, 63% of subjects with traumatic brain injury and 20% of controls had moderate overall disability. Subjects with traumatic brain injury showed more severe neurobehavioural, post-traumatic stress and depression symptoms along with more frequent cognitive performance deficits and more substantial headache impairment than control subjects. Logistic regression modelling using only acute measures identified that a diagnosis of traumatic brain injury, older age, and more severe post-traumatic stress symptoms provided a good prediction of later adverse global outcomes (area under the receiver-operating characteristic curve = 0.84). Thus, US military personnel with concussive blast-related traumatic brain injury in Afghanistan who returned to duty still fared quite poorly on many clinical outcome measures 6-12 months after injury. Poor global outcome seems to be largely driven by psychological health measures, age, and traumatic brain injury status. The effects of early interventions and longer term implications of these findings are unknown. PMID:25740219

  17. In Silico Investigation of Intracranial Blast Mitigation with Relevance to Military Traumatic Brain Injury

    E-print Network

    Nyein, Michelle K.

    Blast-induced traumatic brain injury is the most prevalent military injury in Iraq and Afghanistan, yet little is known about the mechanical effects of blasts on the human head, and still less is known about how personal ...

  18. June 7 Ballistic Blast Results in Solar Tsunami - Duration: 0:08.

    NASA Video Gallery

    In addition to the magnificent blast, SDO detected a shadowy shock wave issuing from the blast site on the June 7, 2011 event. The 'solar tsunami' propagated more than halfway across the sun, visib...

  19. Design of a composite combat helmet liner for prevention of blast-induced traumatic brain injury

    E-print Network

    Vechart, Andrew (Andrew Peter)

    2011-01-01

    Air blast-induced traumatic brain injuries (TBIs) represent a significant percentage of military personnel injuries observed in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF). Prevalence of blast-induced ...

  20. First Cases of Degenerative Brain Disease CTE Found in Veterans with Blast Injuries

    MedlinePLUS

    ... degenerative brain disease CTE found in veterans with blast injuries Follow NINDSnews For release: Friday, June 29, 2012 Some veterans who experience blast-related head injuries on the battlefield can develop ...

  1. Plastic Media Blasting (PMB) waste treatment technology

    SciTech Connect

    Jermyn, H. (Air Force Engineering and Services Center, Tyndall AFB, FL (USA)); Wichner, R.P. (Oak Ridge National Lab., TN (USA))

    1991-10-18

    Environmental and occupational hazard regulations have motivated consideration of several new developments in paint removal technology. Plastic Media Blasting (PMB)/paint wastes consist predominantly of degraded plastic media plus the stripped paint. They are, in general, placed in the category of being characteristically hazardous'' according to the definition in the RCRA Act because of the excess leachability of toxic metals. The objective of the studies described in this paper is the identification and development of optimum methods for treating PMB/paint stripping wastes, particularly the type of such wastes generated by depainting operations performed at Hill Air Force Base. An optimum treatment method would be one which minimizes disposal costs, generally by waste volume reduction, and which results in a nonhazardous solidified product according to the established EPA criteria. The work has progressed in three phases. In Phase 1, the physical properties of the waste material were determined and full range of treatment methods were tested and evaluated. Phase 2 concentrated on a few selected treatments and encapsulation methods. Phase 3, which is currently in its early setup stages, is a demonstration test being conducted at Hill Air Force Base. 6 refs., 3 figs., 4 tabs.

  2. Proteomic sample preparation for blast wound characterization

    PubMed Central

    2014-01-01

    Background Blast wounds often involve diverse tissue types and require substantial time and treatment for appropriate healing. Some of these subsequent wounds become colonized with bacteria requiring a better understanding of how the host responds to these bacteria and what proteomic factors contribute wound healing outcome. In addition, using reliable and effective proteomic sample preparation procedures can lead to novel biomarkers for improved diagnosis and therapy. Results To address this need, suitable sample preparation for 2-D DIGE proteomic characterization of wound effluent and serum samples from combat-wounded patients was investigated. Initial evaluation of crude effluent and serum proved the necessity of high abundant protein depletion. Subsequently, both samples were successfully depleted using Agilent Multiple Affinity Removal system and showed greatly improved 2-D spot maps, comprising 1,800 and 1,200 protein spots, respectively. Conclusion High abundant protein removal was necessary for both wound effluent and serum. This is the first study to show a successful method for high abundant protein depletion from wound effluent which is compatible with downstream 2-D DIGE analysis. This development allows for improved biomarker discovery in wound effluent and serum samples. PMID:24529238

  3. Simulation Assisted Risk Assessment: Blast Overpressure Modeling

    NASA Technical Reports Server (NTRS)

    Lawrence, Scott L.; Gee, Ken; Mathias, Donovan; Olsen, Michael

    2006-01-01

    A probabilistic risk assessment (PRA) approach has been developed and applied to the risk analysis of capsule abort during ascent. The PRA is used to assist in the identification of modeling and simulation applications that can significantly impact the understanding of crew risk during this potentially dangerous maneuver. The PRA approach is also being used to identify the appropriate level of fidelity for the modeling of those critical failure modes. The Apollo launch escape system (LES) was chosen as a test problem for application of this approach. Failure modes that have been modeled and/or simulated to date include explosive overpressure-based failure, explosive fragment-based failure, land landing failures (range limits exceeded either near launch or Mode III trajectories ending on the African continent), capsule-booster re-contact during separation, and failure due to plume-induced instability. These failure modes have been investigated using analysis tools in a variety of technical disciplines at various levels of fidelity. The current paper focuses on the development and application of a blast overpressure model for the prediction of structural failure due to overpressure, including the application of high-fidelity analysis to predict near-field and headwinds effects.

  4. Blast induced mild traumatic brain injury/concussion: A physical analysis

    NASA Astrophysics Data System (ADS)

    Kucherov, Yan; Hubler, Graham K.; DePalma, Ralph G.

    2012-11-01

    Currently, a consensus exists that low intensity non-impact blast wave exposure leads to mild traumatic brain injury (mTBI). Considerable interest in this "invisible injury" has developed in the past few years but a disconnect remains between the biomedical outcomes and possible physical mechanisms causing mTBI. Here, we show that a shock wave travelling through the brain excites a phonon continuum that decays into specific acoustic waves with intensity exceeding brain tissue strength. Damage may occur within the period of the phonon wave, measured in tens to hundreds of nanometers, which makes the damage difficult to detect using conventional modalities.

  5. No. 5 blast furnace 1995 reline and upgrade

    SciTech Connect

    Kakascik, T.F. Jr.

    1996-12-31

    The 1995 reline of No. 5 Blast Furnace is an undertaking which has never been approached in previous relines of any blast furnace in the history of Wheeling Pittsburgh Steel Corporation. The scope of the project is such that it represents a radical departure from W.P.S.C.`s traditional methods of ironmaking. The reline of No. 5 Blast Furnace is one of the largest capital improvements performed at W.P.S.C. Blast Furnaces. The improvements made at one single time are taking a furnace from 1960`s technology into the 21st century. With this in mind, employee training was one of the largest parts of the project. Training for the automated stockhouse, castfloor, new skip drive, new instrumentation, new castfloor equipment, hydraulics and overall furnace operation were an absolute necessity. The reline has laid the ground work to give the Corporation an efficient, higher productive, modern Blast Furnace which will place W.P.S.C. in the world class category in ironmaking well into the 21st century.

  6. Atmospheric particulate emissions from dry abrasive blasting using coal slag

    SciTech Connect

    Bhaskar Kura; Kalpalatha Kambham; Sivaramakrishnan Sangameswaran; Sandhya Potana [University of New Orleans, New Orleans, LA (United States). Department of Civil and Environmental Engineering

    2006-08-15

    Coal slag is one of the widely used abrasives in dry abrasive blasting. Atmospheric emissions from this process include particulate matter (PM) and heavy metals, such as chromium, lead, manganese, nickel. Quantities and characteristics of PM emissions depend on abrasive characteristics and process parameters. Emission factors are key inputs to estimate emissions. Experiments were conducted to study the effect of blast pressure, abrasive feed rate, and initial surface contamination on total PM (TPM) emission factors for coal slag. Rusted and painted mild steel surfaces were used as base plates. Blasting was carried out in an enclosed chamber, and PM was collected from an exhaust duct using U.S. Environment Protection Agency source sampling methods for stationary sources. Results showed that there is significant effect of blast pressure, feed rate, and surface contamination on TPM emissions. Mathematical equations were developed to estimate emission factors in terms of mass of emissions per unit mass of abrasive used, as well as mass of emissions per unit of surface area cleaned. These equations will help industries in estimating PM emissions based on blast pressure and abrasive feed rate. In addition, emissions can be reduced by choosing optimum operating conditions. 40 refs., 5 figs., 2 tabs.

  7. 3D Tomographic imaging of colliding cylindrical blast waves

    NASA Astrophysics Data System (ADS)

    Smith, R. A.; Lazarus, J.; Hohenberger, M.; Robinson, J.; Marocchino, A.; Chittenden, J.; Dunne, M.; Moore, A.; Gumbrell, E.

    2007-11-01

    The interaction of strong shocks & radiative blast waves is believed to give rise to the turbulent, knotted structures commonly observed in extended astrophysical objects. Modeling these systems is however extremely challenging due to the complex interplay between hydrodynamics, radiation and atomic physics. As a result we have been developing laboratory scale blast wave collision experiments to provide high quality data for code benchmarking, & to improve our physical understanding. We report on experimental & numerical investigations of the collision dynamics of counter propagating strong (>Mach 50) cylindrical thin-shelled blast waves driven by focusing intense laser pulses into an extended medium of atomic clusters. In our test system the blast wave collision creates strongly asymmetric electron density profiles, precluding the use of Abel inversion methods. In consequence we have employed a new tomographic imaging technique, allowing us to recover the full 3D, time framed electron density distribution. Tomography & streaked Schlieren imaging enabled tracking of radial & longitudinal mass flow & the investigation of Mach stem formation as pairs of blast waves collided. We have compared our experimental system to numerical simulations by the 3D magnetoresistive hydrocode GORGON.

  8. A $55 Shock Tube for Simulated Blast Waves

    E-print Network

    Courtney, Elijah; Courtney, Michael

    2015-01-01

    Shock tubes are commonly employed to test candidate armor materials, validate numerical models, and conduct simulated blast experiments in animal models. As DoD interests desire to field wearable sensors as blast dosimeters, shock tubes may also serve for calibration and testing of these devices. The high blast pressures needed for experimental testing of candidate armors are unnecessary to test these sensors. An inexpensive, efficient, and easily available way of testing these pressure sensors is desirable. It is known that releasing compressed gas suddenly can create a repeatable shock front, and the pressures can be finely tuned by changing the pressure to which the gas is compressed. A Crosman 0.177 caliber air pistol was used (without loading any pellets) to compress and release air in one end of a 24 inch long 3/4 inch diameter standard pipe nipple to simulate a blast wave at the other end of the tube. A variable number of pumps were used to vary the peak blast pressure. As expected, the trials where 10...

  9. Quick reproduction of blast-wave flow-field properties of nuclear, TNT, and ANFO explosions

    Microsoft Academic Search

    C. P. T. Groth

    1986-01-01

    In many instances, extensive blast-wave flow-field properties are required in gasdynamics research studies of blast-wave loading and structure response, and in evaluating the effects of explosions on their environment. This report provides a very useful computer code, which can be used in conjunction with the DNA Nuclear Blast Standard subroutines and code, to quickly reconstruct complete and fairly accurate blast-wave

  10. NASA CONNECT Data Analysis and Measurement: Having a Solar Blast!

    NSDL National Science Digital Library

    2012-08-03

    This is an activity about the solar cycle. Learners will use X-ray data from the Geostationary Operational Environmental Satellite (GOES) and record the total number of solar flares in their birth month over the course of eleven years and compute the percentage of high-energy X-ray flares which occur for each year. Learners will graph their findings to help them identify the long term pattern of flare activity on the Sun.

  11. Comparison of capillary zone electrophoresis performance of powder-blasted and hydrogen fluoride-etched microchannels in glass

    Microsoft Academic Search

    Qiao-Sheng Pu; Regina Lüttge; Han J. G. E. Gardeniers; Berg van den Albert

    2003-01-01

    The applicability of glass chips with powder-blasted microchannels for electrophoretic separations was examined, and the performance was compared to microchannels etched with hydrogen fluoride (HF), using bicarbonate buffer and rhodamine B and fluorescein as model compounds. The measured electroosmotic mobilities in all chips were comparable, with values of ca. 7×10-4 cm2 V-1s-1. The effect of electrical field strength and detection

  12. Improvement of the early-age reactivity of fly ash and blast furnace slag cementitious systems using limestone filler

    Microsoft Academic Search

    Pierre Mounanga; Muhammad Irfan Ahmad Khokhar; Rana El Hachem; Ahmed Loukili

    2011-01-01

    This article analyzes the effects of the addition of limestone filler on the hydration rate, setting times and early-age mechanical\\u000a properties of binary and ternary-binder mortars containing Portland cement, blast furnace slag (BFS) and fly ash (FA), with\\u000a various substitution rates of cement with mineral additions going up to 50%. Vicat needle penetration tests and measurements\\u000a of heat flow of

  13. BLAST 2 S equences, a new tool for comparing protein and nucleotide sequences

    Microsoft Academic Search

    Tatiana A. Tatusova; Thomas L. Madden

    1999-01-01

    `BLAST 2 Sequences', a new BLAST-based tool for aligning two protein or nucleotide sequences, is described. While the standard BLAST program is widely used to search for homologous sequences in nucleotide and protein databases, one often needs to compare only two sequences that are already known to be homologous, coming from related species or, e.g. different isolates of the same

  14. Bomb blast, mild traumatic brain injury and psychiatric morbidity: A review

    Microsoft Academic Search

    Jeffrey V. Rosenfeld; Nick L. Ford

    2010-01-01

    Traumatic brain injury (TBI) arising from blast exposure during war is common, and frequently complicated by psychiatric morbidity. There is controversy as to whether mild TBI from blast is different from other causes of mild TBI. Anxiety and affective disorders such as Post-traumatic Stress Disorder (PTSD) and depression are common accompaniments of blast injury with a significant overlap in the

  15. 29 CFR 1926.905 - Loading of explosives or blasting agents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...agents shall be left unattended at the blast site. (h) Machines and all tools...with explosives shall be permitted in a blast area. (j) Powerlines and portable...holes. Cables in the proximity of the blast area shall be deenergized and locked...

  16. Development of strategies to manage rice blast disease in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease has been a serious threat to stable rice production in the southern USA. Blast disease has been causing yield losses for decades. Severity of blast epidemics has been always influenced by a combination of the following three factors: 1) rice cultivars deployed with different comb...

  17. Impact of complex blast waves on the human head: a computational study.

    PubMed

    Tan, Long Bin; Chew, Fatt Siong; Tse, Kwong Ming; Chye Tan, Vincent Beng; Lee, Heow Pueh

    2014-12-01

    Head injuries due to complex blasts are not well examined because of limited published articles on the subject. Previous studies have analyzed head injuries due to impact from a single planar blast wave. Complex or concomitant blasts refer to impacts usually caused by more than a single blast source, whereby the blast waves may impact the head simultaneously or consecutively, depending on the locations and distances of the blast sources from the subject, their blast intensities, the sequence of detonations, as well as the effect of blast wave reflections from rigid walls. It is expected that such scenarios will result in more serious head injuries as compared to impact from a single blast wave due to the larger effective duration of the blast. In this paper, the utilization of a head-helmet model for blast impact analyses in Abaqus(TM) (Dassault Systemes, Singapore) is demonstrated. The model is validated against studies published in the literature. Results show that the skull is capable of transmitting the blast impact to cause high intracranial pressures (ICPs). In addition, the pressure wave from a frontal blast may enter through the sides of the helmet and wrap around the head to result in a second impact at the rear. This study recommended better protection at the sides and rear of the helmet through the use of foam pads so as to reduce wave entry into the helmet. The consecutive frontal blasts scenario resulted in higher ICPs compared with impact from a single frontal blast. This implied that blast impingement from an immediate subsequent pressure wave would increase severity of brain injury. For the unhelmeted head case, a peak ICP of 330?kPa is registered at the parietal lobe which exceeds the 235?kPa threshold for serious head injuries. The concurrent front and side blasts scenario yielded lower ICPs and skull stresses than the consecutive frontal blasts case. It is also revealed that the additional side blast would only significantly affect ICPs at the temporal and parietal lobes when compared with results from the single frontal blast case. By analyzing the pressure wave flow surrounding the head and correlating them with the consequential evolution of ICP and skull stress, the paper provides insights into the interaction mechanics between the concomitant blast waves and the biological head model. PMID:25132676

  18. Mathematics needed for Introduction to Transport Phenomena

    NSDL National Science Digital Library

    Krane, Matthew J. M.

    2007-10-12

    A collection of math problems based on skills needed to successfully complete homework problems in an introductory course in Transport Phenomena. These problems do not introduce any new material for those who have taken Freshman Calculus classes and a sophomore level Differential Equations class. At Purdue University in the required Transport Phenomena course for MSE undergrads (MSE 340), I give a problem set like this the first day of classes in order to make clear the level of mathematical skill needed for the rest of the semester. I have found that it reduces difficulties with math later in the semester, allowing the students to focus on the transport phenomena.

  19. Reconstruction of blast injuries of the hand and upper limb.

    PubMed

    Bakhach, Joseph; Abu-Sitta, Ghassan; Dibo, Saad

    2013-03-01

    Over recent years, hand surgeons in the Middle East and Arabic region have particularly had to deal with an increasing number of war blast injuries to the upper extremity, in the acute, subacute and chronic phases. Many have been referred from War Zone countries such as Iraq and, more recently, Syria, where the resources to treat such complex injuries are scarce. The present article is a comprehensive review of the basic principles of management of blast injuries based on the available literature merged with the authors' personal experience of these injuries. The state of the art in treatment of blast injuries to the hand, from ammunition physics and wound ballistics to radiological investigation and, ultimately, the principles of surgical management are discussed. PMID:23357578

  20. Modeling and Simulating Blast Effects on Electric Substations

    SciTech Connect

    Lyle G. Roybal; Robert F. Jeffers; Kent E. McGillivary; Tony D. Paul; Ryan Jacobson

    2009-05-01

    A software simulation tool was developed at the Idaho National Laboratory to estimate the fragility of electric substation components subject to an explosive blast. Damage caused by explosively driven fragments on a generic electric substation was estimated by using a ray-tracing technique to track and tabulate fragment impacts and penetrations of substation components. This technique is based on methods used for assessing vulnerability of military aircraft and ground vehicles to explosive blasts. An open-source rendering and ray-trace engine was used for geometric modeling and interactions between fragments and substation components. Semi-empirical material interactions models were used to calculate blast parameters and simulate high-velocity material interactions between explosively driven fragments and substation components. Finally, a Monte Carlo simulation was added to model the random nature of fragment generation allowing a skilled analyst to predict failure probabilities of substation components.