WorldWideScience

Sample records for dust bowl migration

  1. Dust Bowl migration as an analog for possible global warming-induced migration from Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Turner, M.H.; Longstreth, J.D.; Johnson, A.K.; Rosenberg, N.J.

    1994-06-01

    As a result of increases in CO{sub 2} and other radiatively important trace gases, scientists have predicted increases in mean worldwide temperatures of 2--5 degrees C over the next 50 to 100 years. Such temperature increases may result in climate modifications that would in turn be associated with increases in drought and desertification and could even change the patterns of the monsoons and tropical rains, which are important to agriculture throughout the world. They predicted that the rise in sea level caused by melting and thermal expansion of glaciers and polar icecaps could flood large population centers, destroying habitation and displacing populations. This will result in approximately 50 million ``environmental refugees`` worldwide, triple the number of today. The expected shifts in precipitation are also likely to result in (1) increased runoff contaminated with pesticides, salts, garbage, sewage, and eroded soil, and (2) drought also leading to increased soil erosion and salinization, as well as depletion of limited water resources. The total impact of global warming on agriculture and human habitation could considerably slow the economic development of some nations and would particularly affect agricultural production. Loss of homes, the inability to raise food, an increased prevalence of disease and worsened economic conditions may drive people to leave their homelands, seeking entry into countries which have more resources and greater resistance to the economic consequences of climatic change. This report looks at the possible environmental impacts and economic impacts of the greenhouse effect on Mexico while using the American Dust Bowl event as an analog.

  2. Saving the Dust Bowl: "Big Hugh" Bennett's Triumph over Tragedy

    Science.gov (United States)

    Smith, Rebecca

    2007-01-01

    In the 1930s, years of injudicious cultivation had devastated 100 million acres of Kansas, Oklahoma, Texas, Colorado, and New Mexico. This was the Dust Bowl, and it exposed a problem that had silently plagued American agriculture for centuries--soil erosion. Farmers, scientists, and the government alike considered it trivial until Hugh Hammond…

  3. Interpreting the Dust Bowl: Teaching Environmental Philosophy through Film.

    Science.gov (United States)

    Gold, John R.; And Others

    1996-01-01

    Provides a discussion of the structure and procedures of a classroom exercise using scenes from "The Grapes of Wrath," to illustrate different environmental philosophies. After viewing scenes from the film, students prepare presentations examining the Dust Bowl from one of four philosophical positions: environmental causation,…

  4. Simulating US Agriculture in a Modern Dust Bowl Drought

    Science.gov (United States)

    Glotter, Michael; Elliott, Joshua

    2016-01-01

    Drought-induced agricultural loss is one of the most costly impacts of extreme weather, and without mitigation, climate change is likely to increase the severity and frequency of future droughts. The Dust Bowl of the 1930s was the driest and hottest for agriculture in modern US history. Improvements in farming practices have increased productivity, but yields today are still tightly linked to climate variation and the impacts of a 1930s-type drought on current and future agricultural systems remain unclear. Simulations of biophysical process and empirical models suggest that Dust-Bowl-type droughts today would have unprecedented consequences, with yield losses approx.50% larger than the severe drought of 2012. Damages at these extremes are highly sensitive to temperature, worsening by approx.25% with each degree centigrade of warming. We find that high temperatures can be more damaging than rainfall deficit, and, without adaptation, warmer mid-century temperatures with even average precipitation could lead to maize losses equivalent to the Dust Bowl drought. Warmer temperatures alongside consecutive droughts could make up to 85% of rain-fed maize at risk of changes that may persist for decades. Understanding the interactions of weather extremes and a changing agricultural system is therefore critical to effectively respond to, and minimize, the impacts of the next extreme drought event.

  5. Lessons from the Dust Bowl: Human-Environment Education on the Great Plains

    Science.gov (United States)

    Porter, Jess

    2012-01-01

    This article documents regional demand for human-environment educational resources via assessment of public knowledge of the environmental crisis known as the Dust Bowl. The steadily eroding knowledge-base on the topic is discussed along with the desire for enhanced Dust Bowl educational resources. Regionally focused educational activities…

  6. I Got Them Dust Bowl Blues: Wind Erosion in the Music of the Southern Great Plains

    Science.gov (United States)

    Lee, J. A.

    2017-12-01

    This paper deals with the role of wind erosion and blowing dust on the music of the Dust Bowl region, a portion of the southern Great Plains of the United States. A defining characteristic of the region is dust storms, and in the 1930s, severe dust storms created dramatic images that came to symbolize all of the economic, social and environmental hardships suffered by the people during the 1930s. The music of the time, by Woody Guthrie and others, suggested that the region was being destroyed, never to recover. The region was resilient, however, and in recent decades, dust has been depicted in songs either as an adversity to be endured or simply as a normal part of life in the area. It may be that blowing dust has become a defining characteristic of the region because of a somewhat warped sense of pride in living in an often-difficult environment.

  7. Influence of Agricultural Operations on Dust Emission During the 1930a Dust Bowl, Baca County, CO, USA.

    Science.gov (United States)

    Hodges, A. T.; Bolles, K.; Forman, S. L.

    2017-12-01

    The drought that struck the U.S. Great Plains during the 1930s was one of the most intensedroughts in the region in the last millennium, spurring a major environmental and public healthcrisis. A prominent explanation for the cause of the "dust bowl" centers on the expansion ofagriculture and poor land management practices leading to widespread soil erosion. Thisprevalent hypothesis largely excludes the impacts of naturally occurring land surface processesthat contribute to eolian erosion and dust emissivity, particularly during periods of drought. Priorwork generally focuses on economic and sociological factors in agricultural decision-making forindividual fields or farms.This study utilizes early aerial photography collected by the Soil Conservation Service in 1936 ofBaca County, Colorado, to identify and quantify spatial relationships between geomorphicprocesses and anthropogenic activities impacting dust emission. From the holdings at theNational Archives, 25 photos covering 125 km2 scanned at 1200dpi are combined into acontinuous mosaic, and geo-referenced at RMSE 78.6 m2 . Detailed land cover analyses areundertaken in ArcGIS to classify uncultivated and cultivated surfaces; cultivated surfaces arefurther divided by surface agricultural operations in relation to erosion and dust emission (e.g.listing, contour furrows, terraces, circuitous plowing, listing, eolian transport, and fallow fieldswith and without vegetation). The classified surface is overlaid with National ResourceConservation Service surveys and Soil Conservation Service reconnaissance surveys of land useand erosion carried out in 1936 to infer to potential emissivity of a given cultivated surface. Inthis way, it becomes possible to evaluate human influence on dust emission in one of theworst-struck counties of the Dust Bowl and potentially identify other causative factors to thissignificant period in American history.

  8. Factors contributing to record-breaking heat waves over the Great Plains during the 1930s Dust Bowl

    Science.gov (United States)

    Cowan, T.; Hegerl, G. C.

    2016-12-01

    Record-breaking summer heat waves that plagued contiguous United States in the 1930s emerged during the decade-long "Dust Bowl" drought. Using high-quality daily temperature observations, the Dust Bowl heat wave characteristics for the Great Plains are assessed using metrics that describe variations in heat wave activity and intensity. We also quantify record-breaking heat waves over the pre-industrial period for 22 CMIP5 model multi-century realisations. The most extreme Great Plains heat wave summers in the Dust Bowl decade (e.g. 1931, 1934, 1936) were pre-conditioned by anomalously dry springs, as measured by proxy drought indices. In general, summer heat waves over the Great Plains develop 15-20 days earlier after anomalously dry springs, and are also significantly longer and hotter, indicative of the importance of land surface feedbacks in heat wave intensification. The majority of pre-industrial climate model experiments capture regionally clustered summer heat waves across North America, although the North Pacific and Atlantic sea surface temperature patterns associated with the heat waves vary considerably between models. Sea surface temperature patterns may be more important for influencing winter and spring precipitation, thus amplifying summer heat waves during drought periods. The synoptic pattern that commonly appeared during the exceptional Dust Bowl heat waves featured an anomalous broad surface pressure ridge straddling an upper level blocking anticyclone over the western United States. This forced significant subsidence and adiabatic warming over the Great Plains, and triggered anomalous southward warm advection over southern regions, prolonging and amplifying the heat waves over central United States. Importantly, the results show that despite the sparsity of stations in the 1930s, homogeneous observations are crucial in accurately quantifying the Dust Bowl decade heat waves, as opposed to solely relying on atmospheric reanalysis.

  9. Migration of Interplanetary Dust and Comets

    Science.gov (United States)

    Ipatov, S. I.; Mather, J. C.

    Our studies of migration of interplanetary dust and comets were based on the results of integration of the orbital evolution of 15,000 dust particles and 30,000 Jupiter-family comets (JFCs) [1-3]. For asteroidal and cometary particles, the values of the ratio β between the radiation pressure force and the gravitational force varied from 1000 and 1 microns. The probability of a collision of a dust particle started from an asteroid or JFC with the Earth during a lifetime of the particle was maximum at diameter d ˜100 microns. For particles started from asteroids and comet 10P, this maximum probability was ˜0.01. Different studies of migration of dust particles and small bodies testify that the fraction of cometary dust particles of the overall dust population inside Saturn's orbit is considerable and can be dominant: (1) Cometary dust particles produced both inside and outside Jupiter's orbit are needed to explain the observed constant number density of dust particles at 3-18 AU. The number density of migrating trans-Neptunian particles near Jupiter's orbit is smaller by a factor of several than that beyond Saturn's orbit. Only a small fraction of asteroidal particles can get outside Jupiter's orbit. (2) Some (less than 0.1%) JFCs can reach typical near-Earth object orbits and remain there for millions of years. Dynamical lifetimes of most of the former JFCs that have typical near-Earth object orbits are about 106 -109 yr, so during most of these times they were extinct comets. Such former comets could disintegrate and produce a lot of mini-comets and dust. (3) Comparison of the velocities of zodiacal dust particles (velocities of MgI line) based on the distributions of particles over their orbital elements obtained in our runs [3-4] with the velocities obtained at the WHAM observations shows that only asteroidal dust particles cannot explain these observations, and particles produced by comets, including high-eccentricity comets, are needed for such explanation

  10. The Paleozoic Dust Bowl: Dust Deposition in Tropical Western Pangaea (Midcontinent U.S.) at the Terminus of the Late Paleozoic Ice Age

    Science.gov (United States)

    Soreghan, G. S.; Heavens, N. G.; Benison, K. C.; Soreghan, M. J.; Mahowald, N. M.; Foster, T.; Zambito, J.; Sweet, A.; Kane, M.

    2012-12-01

    Atmospheric dust is well recognized and studied as both an archive and agent of climate change in Earth's relatively recent past. Archives of past dust include loess deposits and dust recovered from ocean- and ice-cores. Dust remains poorly known in Earth's past prior to the Cenozoic, but is increasingly recognized in the form of paleo-loess deposits, and (epeiric) marine strata that accumulated isolated from fluvio-deltaic influx. Here, we report on the growing recognition of voluminous dust deposits preserved in the Permian record of the U.S. Midcontinent (western tropical Pangaea). Fine-grained redbeds predominate in Permian strata throughout the U.S. Midcontinent, but notably in a swath extending from Oklahoma through South Dakota. These units consist predominantly of red mudstone and siltstone in commonly massive units, but sedimentary structures and bedding that signal aqueous processes (e.g. laminations, ripples) have led most to infer deltaic or tidal deposition. The absence of channel systems to deliver the sediment, as well as the predominantly massive and laterally continuous character and the uniform fine grain size signal wind transport, implying that these units record sustained dust deposition overprinted at times by sub-aqueous deposition in lakes, including ephemeral saline and acid lakes that led to evaporite cementation. Detrital zircon geochronology indicates that much of the dust originated in the relatively distant Appalachian-Ouachita orogenic systems, which formed part of the central Pangaean mountains (CPM), the collisional zone that sutured the supercontinent. Within the Anadarko basin of Oklahoma, Permian redbeds record >2 km of predominantly dust deposition, some of the thickest dust deposits yet documented in Earth's record. Yet the tropical setting is remarkably non-uniformitarian, as much Quaternary loess occurs in mid- to high-latitude regions, commonly linked to glacial genesis. We are currently investigating with both data and

  11. National Science Bowl | NREL

    Science.gov (United States)

    Science Bowl National Science Bowl The Department of Energy's Office of Science sponsors the National Science Bowl competition. This fun, fast-paced academic tournament tests the brainpower of middle and high school student teams on science and math topics. The National Science Bowl provides an

  12. Bowls Club

    CERN Multimedia

    Bowls Club

    2014-01-01

    Bowls Club Pour la 18ème année consécutive se déroulait le  "Challenge Claude CARTERET". Vingt trois personnes ont repondues "présent" et comme d'habitude dans une superbe ambiance, les trois parties avec à chaque fois un changement de partenaire se déroulaient avec acharnement. Notre juge arbitre Claude JOUVE applaudissait les gagnants qui étaient au nombre de quatre à avoir gagné  3 parties et étaient départagés par le goal-avérage. 1er : David JOUVE avec moins d'entraînement que le papa et son oncle mais qui est un battant 2ème: christian JOUVE (oncle de David) qui se fait donc coiffer au goal-avérage 3ème : Un nouveau venu très talentueux et adroit surnommé Mousse. Et notre pr...

  13. Bowls Club

    CERN Multimedia

    Club de Pétanque

    2014-01-01

    Bowls Club   Par une belle fin de journée ensoleillée se déroulait le deuxième concours de la saison, le Challenge de notre ami "Patrick DURAND" qui a été membre du club et œuvré pour le celui-ci pendant  près de vingt ans. Un bel hommage lui était rendu par la présence de quarante personnes. Trente deux personnes ont participé au concours, soit seize doublettes. Des parties très disputées : quatre participants ont gagné les trois parties et ont dû être départagés par le goal average. Notre juge arbitre et  trésorier, Claude JOUVE,  proclamait vainqueur un habitué des podiums : Bernard GOICOECHEA qui  tenait  particulièrement à cœur de gagner ce challenge. Le deuxième ...

  14. Does the source migration pathway of HBCDs to household dust influence their bio-accessibility?

    Energy Technology Data Exchange (ETDEWEB)

    García-Alcega, Sonia [Soil Research Centre, University of Reading, Reading RG6 6AH (United Kingdom); Rauert, Cassie; Harrad, Stuart [School of Geography Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT (United Kingdom); Collins, Chris D., E-mail: c.d.collins@reading.ac.uk [Soil Research Centre, University of Reading, Reading RG6 6AH (United Kingdom)

    2016-11-01

    A study was conducted to assess the human bioaccessibility of dust contaminated with hexabromocyclododecane (HBCD) via two migration pathways a) volatilisation with subsequent partitioning to dust particles, and b) abrasion of treated textile fibres directly to the dust. This was achieved using previously developed experimental chamber designs to generate dust samples contaminated with HBCDs emitted from a HBCD treated textile curtain. The generated dust samples were exposed to an in vitro colon extended physiologically based extraction test (CE-PBET). The bioaccessibility of the HBCDs which were incorporated within dust as a result of volatilisation from the curtain material with subsequent partitioning to dust was higher than in dusts contaminated with HBCDs via abrasion of the curtain (35% and 15% respectively). We propose this occurs due to a stronger binding of HBCDs to treated fabric fibres than that experienced following volatilisation and sorption of HBCDs to dust particles. - Highlights: • Migration pathways via which HBCDs enter dust influences its bioaccessibility. • HBCDs more bioaccessible when incorporated to dust via volatilisation. • Contamination of dusts is more variable via abrasion than volatilisation.

  15. Does the source migration pathway of HBCDs to household dust influence their bio-accessibility?

    International Nuclear Information System (INIS)

    García-Alcega, Sonia; Rauert, Cassie; Harrad, Stuart; Collins, Chris D.

    2016-01-01

    A study was conducted to assess the human bioaccessibility of dust contaminated with hexabromocyclododecane (HBCD) via two migration pathways a) volatilisation with subsequent partitioning to dust particles, and b) abrasion of treated textile fibres directly to the dust. This was achieved using previously developed experimental chamber designs to generate dust samples contaminated with HBCDs emitted from a HBCD treated textile curtain. The generated dust samples were exposed to an in vitro colon extended physiologically based extraction test (CE-PBET). The bioaccessibility of the HBCDs which were incorporated within dust as a result of volatilisation from the curtain material with subsequent partitioning to dust was higher than in dusts contaminated with HBCDs via abrasion of the curtain (35% and 15% respectively). We propose this occurs due to a stronger binding of HBCDs to treated fabric fibres than that experienced following volatilisation and sorption of HBCDs to dust particles. - Highlights: • Migration pathways via which HBCDs enter dust influences its bioaccessibility. • HBCDs more bioaccessible when incorporated to dust via volatilisation. • Contamination of dusts is more variable via abrasion than volatilisation.

  16. Tea Bowl: Imperfect Harmony

    OpenAIRE

    Mehring, Gretchen A; Greater Lafayette Museum of Art,

    1998-01-01

    These tea bowls, with their intimate scale and individual personalities, simultaneeously offer an apprectiation of the past and the contemporary. The subtle beauty of traditional-style bowls contrasts with the more exuberant contemporary idiom, raising an awareness of the role that art has, and can play, in everyday life.

  17. Double bowl piston

    Science.gov (United States)

    Meffert, Darrel Henry; Urven, Jr., Roger Leroy; Brown, Cory Andrew; Runge, Mark Harold

    2007-03-06

    A piston for an internal combustion engine is disclosed. The piston has a piston crown with a face having an interior annular edge. The piston also has first piston bowl recessed within the face of the piston crown. The first piston bowl has a bottom surface and an outer wall. A line extending from the interior annular edge of the face and tangent with the outer wall forms an interior angle greater than 90 degrees with the face of the piston. The piston also has a second piston bowl that is centrally located and has an upper edge located below a face of the piston crown.

  18. Migration of DEHP and DINP into dust from PVC flooring products at different surface temperature.

    Science.gov (United States)

    Jeon, Seunghwan; Kim, Ki-Tae; Choi, Kyungho

    2016-03-15

    Phthalates are important endocrine disrupting chemicals that have been linked to various adverse human health effects. Phthalates are ubiquitously present in indoor environment and could enter humans. Vinyl or PVC floorings have been recognized as one of important sources of phthalate release to indoor environment including house dust. In the present study, we estimated the migration of di(2-ethylhexyl)phthalate (DEHP) and di-isononyl phthalate (DINP) from the flooring materials into the dust under different heating conditions. For this purpose, a small chamber specifically designed for the present study and a Field and Laboratory Emission Cell (FLEC) were used, and four major types of PVC flooring samples including two UV curing paint coated, an uncoated residential, and a wax-coated commercial type were tested. Migration of DEHP was observed for an uncoated residential type and a wax-coated commercial type flooring. After 14 days of incubation, the levels of DEHP in the dust sample was determined at room temperature on average (standard deviation) at 384 ± 19 and 481 ± 53 μg/g, respectively. In contrast, migration of DINP was not observed. The migration of DEHP was strongly influenced by surface characteristics such as UV curing coating. In the residential flooring coated with UV curing paint, migration of DEHP was not observed at room temperature. But under the heated condition, the release of DEHP was observed in the dust in the FLEC. Migration of DEHP from flooring materials increased when the flooring was heated (50 °C). In Korea, heated flooring system, or 'ondol', is very common mode of heating in residential setting, therefore the contribution of PVC flooring to the total indoor DEHP exposure among general population is expected to be greater especially during winter season when the floor is heated. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Tibetan singing bowls

    International Nuclear Information System (INIS)

    Terwagne, Denis; Bush, John W M

    2011-01-01

    We present the results of an experimental investigation of the acoustics and fluid dynamics of Tibetan singing bowls. Their acoustic behaviour is rationalized in terms of the related dynamics of standing bells and wine glasses. Striking or rubbing a fluid-filled bowl excites wall vibrations, and concomitant waves at the fluid surface. Acoustic excitation of the bowl's natural vibrational modes allows for a controlled study in which the evolution of the surface waves with increasing forcing amplitude is detailed. Particular attention is given to rationalizing the observed criteria for the onset of edge-induced Faraday waves and droplet generation via surface fracture. Our study indicates that drops may be levitated on the fluid surface, induced to bounce on or skip across the vibrating fluid surface. (invited article)

  20. Migration of Small Bodies and Dust to Near-Earth Space

    Science.gov (United States)

    Ipatov, S. I.; Mather, J. C.

    Computer simulations of the orbital evolution of Jupiter-family comets (JFCs), resonant asteroids, and asteroidal, kuiperoidal, and cometary dust particles were made. The gravitational influence of planets (exclusive of Pluto and sometimes of Mercury) was taken into account. For dust particles we also considered radiation pressure, Poynting-Robertson drag, and solar wind drag. A few JFCs got Earth-crossing orbits with semi-major axes adisintegrated into mini-comets and dust during a smaller part of their dynamical lifetimes if these lifetimes are not small. The obtained results show that during the accumulation of the giant planets the total mass of icy bodies delivered to the Earth could be about the mass of water in Earth's oceans. In our runs for dust particles, the values of the ratio β between the radiation pressure force and the gravitational force varied from 0.0004 to 0.4 (for silicates, such values correspond to particle diameters between 1000 and 1 microns). For β >0.01 the collision probabilities of dust particles with the terrestrial planets during lifetimes of particles were considerably greater for larger asteroidal and cometary particles. At β ≥ 0.1 and β ≤ 0.001 some asteroidal particles migrated beyond Jupiter's orbit. The peaks in the distribution of migrating asteroidal dust particles with semi-major axis corresponding to the n:(n+1) resonances with Earth and Venus and the gaps associated with the 1:1 resonances with these planets are more pronounced for larger particles. Several our papers on this problem were put in http://arXiv.org/format/astro-ph/ (e.g., 0305519, 0308448, 0308450). This work was supported by INTAS (00-240) and NASA (NAG5-10776).

  1. Mass transfer of PBDEs from plastic TV casing to indoor dust via three migration pathways — A test chamber investigation

    International Nuclear Information System (INIS)

    Rauert, C.; Harrad, S.

    2015-01-01

    Polybrominated diphenyl ethers (PBDEs) are widely detected in humans with substantial exposure thought to occur in indoor environments and particularly via contact with indoor dust. Despite this, knowledge of how PBDEs migrate to indoor dust from products within which they are incorporated is scarce. This study utilises an in-house designed and built test chamber to investigate the relative significance of different mechanisms via which PBDEs transfer from source materials to dust, using a plastic TV casing treated with the Deca-BDE formulation as a model source. Experiments at both room temperature and 60 °C revealed no detectable transfer of PBDEs from the TV casing to dust via volatilisation and subsequent partitioning. In contrast, substantial transfer of PBDEs to dust was detected when the TV casing was abraded using a magnetic stirrer bar. Rapid and substantial PBDE transfer to dust was also observed in experiments in which dust was placed in direct contact with the source. Based on these experiments, we suggest that for higher molecular weight PBDEs like BDE-209; direct dust:source contact is the principal pathway via which source-to-dust transfer occurs. - Highlights: • Transfer from a TV casing to dust of high molecular weight PBDEs examined. • Direct source:dust contact effected rapid and most substantial transfer. • Substantial source:dust transfer also occurred via abrasion of source

  2. The bowling balls

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    10 November 1972: CERN’s Bent Stumpe places an order for 12 bowling balls for a total cost of 95 US dollars. Although not evident at first sight, he is buying the heart of some of the first tracking devices to be used in the SPS control room. Today, Bent Stumpe’s device would be called a desktop mouse…   The first order for 4 bowling balls later changed to 12 balls. The bowling balls became the heart of Bent Stumpe's mouse. Almost 40 years ago, the web, Wikipedia and Google did not exist and it was much more difficult to know whether other people in other parts of the world or even in the same laboratory were facing the same problems or developing the same tools. At that time, Bent Stumpe was an electronics engineer, newly recruited to work on developments for the SPS Central Control room. One of the things his supervisor asked him to build as soon as possible was a device to control a pointer on a screen, also called a tracker ball. The heart of the device was the...

  3. Teematapahtuma Space Bowling & Billiardsiin

    OpenAIRE

    Filppu, Mika

    2014-01-01

    Tässä opinnäytetyössä esitellään suunnitelma täysin uudenlaisen teematapahtuman järjestämiseksi ja markkinoimiseksi Space Bowling & Billiardsiin, Tampereelle. Työssä teoriaosuus koostuu markkinoinnista, tapahtuman järjestämisestä, sekä benchmarkingista. Markkinointiosuus sisältää markkinoinnin määritelmän, perusteet, markkinoinnin kehityksen nykypäivään asti, sekä markkinoinnin kilpailukeinot ja sissimarkkinointia. Tapahtuman järjestäminen käydään läpi vaihe vaiheelta suunnitteluvaiheesta jäl...

  4. Croquet and lawn bowls

    CERN Multimedia

    Croquet Club

    2010-01-01

    The club is looking for new members. Why not try a new sport this summer? Croquet is a game of skill, where accuracy and tactics are equally important. It is good fun and Social Nights on Mondays, ending with a bbq, are very popular. We organise internal tournaments and our top players compete in European and World championships. Coaching is offered in both the simpler golf croquet and the more tactical Association versions of the game, starting early May. We have two lawns and a clubhouse on the Prévessin site, with bar and barbecue. All playing equipment is provided. Lawn bowls is also played, mainly on Wednesday mornings.   For further information please contact: Croquet: Norman Eatough Email: norferga@orange.fr Tel. 0033 450 412187 Lawn bowls: Denis Hill Email: denis.hill@freesurf.ch Tél. 022 757 2556 Le club cherche de nouveaux membres. Pourquoi pas entamer un nouveau sport cet été? Un cours d’initiation au croquet est offert. ...

  5. Introducing the Medical Ethics Bowl.

    Science.gov (United States)

    Merrick, Allison; Green, Rochelle; Cunningham, Thomas V; Eisenberg, Leah R; Hester, D Micah

    2016-01-01

    Although ethics is an essential component of undergraduate medical education, research suggests that current medical ethics curricula face considerable challenges in improving students' ethical reasoning. This article discusses these challenges and introduces a promising new mode of graduate and professional ethics instruction for overcoming them. We begin by describing common ethics curricula, focusing in particular on established problems with current approaches. Next, we describe a novel method of ethics education and assessment for medical students that we have devised: the Medical Ethics Bowl (MEB). Finally, we suggest the pedagogical advantages of the MEB when compared to other ethics curricula.

  6. Katrina in Historical Context: Environment and Migration in the U.S.

    Science.gov (United States)

    Gutmann, Myron P; Field, Vincenzo

    2010-01-01

    The massive publicity surrounding the exodus of residents from New Orleans spurred by Hurricane Katrina has encouraged interest in the ways that past migration in the U.S. has been shaped by environmental factors. So has Timothy Egan's exciting book, The Worst Hard Time: The Untold Story of those who survived the Great American Dust Bowl. This paper places those dramatic stories into a much less exciting context, demonstrating that the kinds of environmental factors exemplified by Katrina and the Dust Bowl are dwarfed in importance and frequency by the other ways that environment has both impeded and assisted the forces of migration. We accomplish this goal by enumerating four types of environmental influence on migration in the U.S.: 1) environmental calamities, including floods, hurricanes, earthquakes, and tornadoes, 2) environmental hardships and their obverse, short-term environmental benefits, including both drought and short periods of favorable weather, 3) environmental amenities, including warmth, sun, and proximity to water or mountains, and 4) environmental barriers and their management, including heat, air conditioning, flood control, drainage, and irrigation. In U.S. history, all four of these have driven migration flows in one direction or another. Placing Katrina into this historical context is an important task, both because the environmental calamities of which Katrina is an example are relatively rare and have not had a wide impact, and because focusing on them defers interest from the other kinds of environmental impacts, whose effect on migration may have been stronger and more persistent, though less dramatic.

  7. 25 Years of AAPT's PhysicsBowl

    Science.gov (United States)

    Faleski, Michael C.

    2010-01-01

    The PhysicsBowl is a contest for high school students that was first introduced in 1985. In this article, we discuss both some of the history of the contest as well as the 25th contest occurring this year.

  8. Storytelling Revealed in Super Bowl 2016 Advertisements

    OpenAIRE

    Rellahan, Celina

    2016-01-01

    This thesis investigates the use of storytelling in advertising applications and its influence on the instigation of social activity as measured by online views and social activity generated for advertisements broadcast during the 2016 Super Bowl. The thesis aims at identifying those elements of storytelling that are found in these advertisements and relating these characteristics to the success of the promotion in terms of immediate engagement of the viewing audience. The thesis present...

  9. Vinča bowls with protoma

    Directory of Open Access Journals (Sweden)

    Spasić Miloš P.

    2014-01-01

    Full Text Available Bowls with protoma represent one of several tens of types of Vinča vessels made of baked clay which have been published as finds excavated at Vinča sites for more than a century. We are dealing here with bowls of a markedly conical profile, with angled and slightly rounded walls and with a flat or slightly annular bottom. In most cases these bowls are not decorated, with the exception of the rare finds decorated by fluting, engraving and polishing. Their most significant peculiarity is the presence of four or eight protoma on the rim, facing the inside of the vessel. Taking into consideration all stylistic-typological characteristics, it is possible to divide them into two coherent categories of finds. The first consists of bowls with four oppositely placed protoma. Within this group it is possible to single out two subtypes, bowls with all four as anthropomorphic (Pl. I/6, 7; Pl. III/34 or all four as zoomorphic representations (Pl. I/5, 8, 9; Pl. III/33, 36. Bowls with eight protoma have actually got four pairs of oppositely placed representations. It was possible to discern two subtypes based on the objects that were completely preserved. The first subtype includes a bowl from the so-called Vinča ritual set, with two pairs of zoomorphic and two pairs of anthropomorphic protoma, both oppositely placed (Pl. I/3. The second subtype includes a bowl from house 1/2010 from Stubline with four identical, paired, totally stylised and schematised representations, whose identification is impossible (Fig. 1; Pl. I/1. Taking into consideration the metric and technological data, the thesis that seems most possible is that the bowls with protoma served for the consumption of or the storing/displaying of the content during some quite specific activities. Bowls with protoma appear in almost all regions of the central Balkans populated by Vinča culture communities and we do not note them in the areas of the neighbouring Late Neolithic communities. These

  10. A special danger in bowling and skittle – bowling ball induced injuries of the distal fingers

    Directory of Open Access Journals (Sweden)

    Könneker, Sören

    2017-09-01

    Full Text Available Purpose: Injuries to the hand and fingers have been reported related to the popular sports of bowling and skittle. Both sports differ regarding size, shape, weight of the ball and technique. The focus of this study is to address whether bowling or skittle players are more prone to injuries. Methods: We assessed hand injuries related to bowling or skittle in a retrospective analysis of patients treated in our department between 2006 and 2016. We also investigated differences between both sports with regards to patient demographics, type and location of lesion, and treatment.Results: A total of 13 patients were identified with minors comprising a total of number of six patients. Six from the overall cohort developed injuries related to bowling, and seven sustained injuries related to skittle. In all cases, the pattern of injury revealed a contusion between two balls during retrieval. The distal phalanx was affected in all patients, and the middle phalanx in one. Out of the 13 patients, one patient presented with lesions on the 3 finger, ten patients on the 4 finger and two patients on the 5 finger. In cases of bone injury (n=10, patients received surgical treatment via K-wire-fixation (n=2, suture-cerclage (n=1, resection of little distal fragments (n=1 or splinting only (n=6. There were no significant differences between patients with bowling or skittle injuries with regard to frequency, type and location of the lesions.Conclusion: Bowling and skittle are comparable with their inherent risk of distal finger trauma. Almost all cases required surgical intervention. As most injuries occurred during retrieval of the ball from the rack, efforts should be put on prevention at this point. In both sports the majority of patients were minor, so age restriction should be evaluated.Level of evidence: Therapeutic study, level IV

  11. Dust Deposition and Migration of the ITCZ through the Last Glacial Cycle in the Central Equatorial Pacific (Line Islands).

    Science.gov (United States)

    Reimi Sipala, M. A.; Marcantonio, F.

    2014-12-01

    Atmospheric dust can be used to record climate change in addition to itself playing a role in several key climate processes, such as affecting Earth's albedo, fomenting rain coalescence, encouraging biological productivity, and enhancing carbon export though particle sinks. Using deep sea sediments, it is possible to quantify and locate the sources and sinks of atmospheric dust. A key area of research is the shift in the inter-tropical converge zone (ITCZ), a thermally influenced area that shifts according to the northern and southern hemisphere temperature gradient. This ongoing project focuses on the changes of the ITCZ over the Central Equatorial Pacific (CEP) over the past ~25000 years. The research focuses on two cores taken from the Line Islands Ridge at 0° 29' N (ML1208-18GC), and 4° 41' N (ML1208-31BB). The main aim is to quantify the magnitude and provenance of windblown dust deposited in the CEP, and to address questions regarding the nature of the variations of dust through ice-age climate transitions. Radiogenic isotopes (Sr, Nd, Pb) have been successfully used to distinguish between different potential dust sources in the aluminosilicates fractions of Pacific Sediments. Our preliminary Pb isotope ratios suggest that, for modern deposition, the northern core's (31BB) detrital sediment fraction is likely sourced from Asian Loess (average ratios are 206Pb/204Pb = 18.88, 207Pb/204Pb = 15.69, 208Pb/204Pb = 39.06). The equatorial core's (18GC) detrital fraction has a less radiogenic Pb signature, which is consistent with South American dust sourcing (206Pb/204Pb = 18.62, 207Pb/204Pb = 15.63, 208Pb/204Pb = 38.62). This is indicative of a strong modern ITCZ that acts as an effective barrier for inter-hemispheric dust transport. Prior to Holocene time, the changes in Pb isotope ratios in both cores appear to be in anti-phase; the northern core becomes less radiogenic up to the LGM, while the southern core becomes more radiogenic. This is potentially due to a

  12. The combined bowling rate as a measure of bowling performance in ...

    African Journals Online (AJOL)

    This classification is however not very accurate as it does for example not take into account how many overs have been bowled. Two bowlers might have the same average but one may be more economical than the other. The purpose of this paper is to introduce a single measure that takes the full performance of a bowler ...

  13. Theoretical considerations in solid bowl centrifugation

    International Nuclear Information System (INIS)

    Hamilton, R.T.

    1979-01-01

    A combination of literature survey and independent analysis determined three relationships for the prediction of the critical (or minimum recoverable) particle size in a solid bowl centrifuge. The relationships were derived based on three different theories of fluid behavior within the centrifuge; (1) laminar film flow (laminar film model), (2) plug flow (Sharples Model), and parabolic flow (modified Sharples Model). The critical particle size for the centrifuge used in Cs-PTA recovery in the CAW process predicted by the three relationships range from 0.19 to 0.34 μm (1 μm = 10 -6 m). The laminar film model gives the most conservative estimate of critical particle size (0.34 μm) and the resulting relationship is recommended for use to predict solid bowl centrifuge performance. Three correction factors are incorporated into the predictive equations to account for the effects of fluid turbulence near the centrifuge feed point, fluid lag and hindered settling. Of these factors, turbulence near the feed point (which is accounted for by using an effective centrifuge length) has the greatest impact, increasing the predicted critical particle size by 15%, while the combination of fluid lag and hindered settling factors increase the recoverable particle size by 4%. The overall effect of the correction factors is an approximately 20% decrease in centrifuge effectivity. The fraction of solids smaller than the critical size range has not been reliably determined for laboratory or plant prepared Cs-PTA. In addition, the density of Cs-PTA crystals is reported to vary from 3.2 to 12 grams per cubic centimeter

  14. Whole blood analysis rotor assembly having removable cellular sedimentation bowl

    Science.gov (United States)

    Burtis, C.A.; Johnson, W.F.

    1975-08-26

    A rotor assembly for performing photometric analyses using whole blood samples is described. Following static loading of a gross blood sample within a centrally located, removable, cell sedimentation bowl, the red blood cells in the gross sample are centrifugally separated from the plasma, the plasm displaced from the sedimentation bowl, and measured subvolumes of plasma distributed to respective sample analysis cuvettes positioned in an annular array about the rotor periphery. Means for adding reagents to the respective cuvettes are also described. (auth)

  15. Overlapping Ballistic Ejecta Fields: Separating Distinct Blasts at Kings Bowl, Idaho

    Science.gov (United States)

    Borg, C.; Kobs-Nawotniak, S. E.; Hughes, S. S.; Sears, D. W. G.; Heldmann, J. L.; Lim, D. S. S.; Haberle, C. W.; Sears, H.; Elphic, R. C.; Kobayashi, L.; Garry, W. B.; Neish, C.; Karunatillake, S.; Button, N.; Purcell, S.; Mallonee, H.; Ostler, B.

    2015-12-01

    Kings Bowl is a ~2200ka pit crater created by a phreatic blast along a volcanic fissure in the eastern Snake River Plain (ESRP), Idaho. The main crater measures approximately 80m in length, 30m in width, and 30m in depth, with smaller pits located nearby on the Great Rift fissure, and has been targeted by the FINESSE team as a possible analogue for Cyane Fossae, Mars. The phreatic eruption is believed to have occurred due to the interaction of groundwater with lava draining back into the fissure following a lava lake high stand, erupting already solidified basalt from this and previous ERSP lava flows. The contemporaneous draw back of the lava with the explosions may conceal some smaller possible blast pits as more lava drained into the newly formed pits. Ballistic ejecta from the blasts occur on both sides of the fissure. To the east, the ballistic blocks are mantled by fine tephra mixed with eolian dust, the result of a westerly wind during the explosions. We use differential GPS to map the distribution of ballistic blocks on the west side of the fissure, recording position, percent vesiculation, and the length of 3 mutually perpendicular axes for each block >20cm along multiple transects parallel to the fissure. From the several hundred blocks recorded, we have been able to separate the ballistic field into several distinct blast deposits on the basis of size distributions and block concentration. The smaller pits identified from the ballistic fields correspond broadly to the northern and southern limits of the tephra/dust field east of the fissure. Soil formation and bioturbation of the tephra by sagebrush have obliterated any tephrostratigraphy that could have been linked to individual blasts. The ballistic block patterns at Kings Bowl may be used to identify distinct ejecta groups in high-resolution imagery of Mars or other planetary bodies.

  16. Tang dynasty (618-907) bowl measured with PIXE

    Science.gov (United States)

    Laitinen, M.; Käyhkö, M.; Hahn, G.; von Uexküll-Güldenband, N.; Sajavaara, T.

    2017-09-01

    Brownish bowl originating from an underwater shipwreck located near Belitung island in the Java Sea, some 600 km south-east from Singapore, has been measured with particle induced X-ray emission. This study was a pilot project for the - now a spin-off company - Recenart research team where one target was to evaluate the authenticity of the different type of art objects. PIXE measurements were done from three different material positions from a single bowl received from a customer. These locations were categorized as a bluish/greenish pigment (under glaze), thick glaze and the body clay. When the obtained data was compared to the other references from different dynasties and kiln sites, the closest match was indeed the Tang dynasty, Tongguan/Ghangsha kiln-site potsherds - from where the bowl in question was also suspected to originate.

  17. Configuration System for Simulation Based Design of Vibratory Bowl Feeders

    DEFF Research Database (Denmark)

    Hansson, Michael Natapon; Mathiesen, Simon; Ellekilde, Lars-Peter

    2017-01-01

    Vibratory bowl feeders are still among the most commonly used production equipment for automated part feeding, where parts are correctly oriented for further manipulation by being conveyed through a set of orienting devices. Designing vibratory bowl feeders involves selecting and sequencing...... a number of these devices that either reorients or rejects the part until a desirable orientation is achieved. To aid the designer in this task, this work presents a configuration system where knowledge of the behaviour for each device is acquired through dynamic simulation, and used to solve...

  18. Cricket: Nature and incidence of fast-bowling injuries at an elite ...

    African Journals Online (AJOL)

    ). Physical fitness screenings were conducted and the relationship between fitness and occurrence of injuries was assessed. Additional factors such as bowling techniques and bowling workload were assessed. A regression analysis was ...

  19. Extraverted children are more biased by bowl sizes than introverts.

    Directory of Open Access Journals (Sweden)

    Koert van Ittersum

    Full Text Available Extraverted children are hypothesized to be most at risk for over-serving and overeating due to environmental cues--such as the size of dinnerware. A within-subject field study of elementary school students found that extraverted children served themselves 33.1% more cereal in larger bowls (16-oz than in smaller (12-oz bowls, whereas introverted children were unaffected by bowl size (+5.6%, ns. However, when children were asked by adults how much cereal they wanted to eat, both extraverted and introverted children requested more cereal when given a large versus small bowl. Insofar as extraverted children appear to be more biased by environmental cues, this pilot study suggests different serving styles are recommended for parents and other caregivers. They should serve extraverts, but allow introverts to serve themselves. Still, since the average child still served 23.2% more when serving themselves than when served by an adult, it might be best for caregivers to do the serving whenever possible--especially for extraverted children.

  20. The Intercollegiate Ethics Bowl: An Active Learning Experience

    Science.gov (United States)

    Meyer, Tracy

    2012-01-01

    This paper introduces the Intercollegiate Ethics Bowl (IEB) as a means of promoting active learning in the realm of marketing ethics. The cases discussed in the competition are based on current ethical issues and require students to provide a coherent analysis of what are generally complex, ambiguous, and highly viewpoint dependent issues. The…

  1. Optimisation of Trap Design for Vibratory Bowl Feeders

    DEFF Research Database (Denmark)

    Mathiesen, Simon; Sørensen, Lars Carøe; Kraft, Dirk

    2018-01-01

    Vibratory bowl feeders (VBFs) are a widely used option for industrial part feeding, but their design is still largely manual. A subtask of VBF design is determining an optimal parameter set for the passive devices, called traps, which the VBF uses to ensure correct part orientation. This paper...

  2. Extraverted Children Are More Biased by Bowl Sizes than Introverts

    Science.gov (United States)

    van Ittersum, Koert; Wansink, Brian

    2013-01-01

    Extraverted children are hypothesized to be most at risk for over-serving and overeating due to environmental cues – such as the size of dinnerware. A within-subject field study of elementary school students found that extraverted children served themselves 33.1% more cereal in larger bowls (16-oz) than in smaller (12-oz) bowls, whereas introverted children were unaffected by bowl size (+5.6%, ns). However, when children were asked by adults how much cereal they wanted to eat, both extraverted and introverted children requested more cereal when given a large versus small bowl. Insofar as extraverted children appear to be more biased by environmental cues, this pilot study suggests different serving styles are recommended for parents and other caregivers. They should serve extraverts, but allow introverts to serve themselves. Still, since the average child still served 23.2% more when serving themselves than when served by an adult, it might be best for caregivers to do the serving whenever possible – especially for extraverted children. PMID:24205166

  3. Marketingové aktivity restaurace "Pizzerie Bowling Litovel"

    OpenAIRE

    Spáčilová, Eva

    2011-01-01

    This Thesis deals with marketing activities of restaurant "Pizzerie Bowling Litovel", that tries to keep its satisfied customers. Theoretical section focuses on the principles of marketing in services, especially in hospitality. The practical section describes the current situation of the restaurant. Through the use of marketing research and competitive analysis, applies the theory on the real project and arrives with plans and recommendations on how to improve the marketing of the restaurant.

  4. The Black Burnished Type 18 Bowl and the Fifth Century

    Directory of Open Access Journals (Sweden)

    James Gerrard

    2016-03-01

    Full Text Available This article discusses a late Roman Black Burnished form known as the Type 18 bowl. The lateness of this form was first discussed in 2004 but new discoveries have continued to reinforce the probably late fourth to early fifth century date assigned to this vessel. Imitations in other fabrics are also beginning to be identified with one such vessel found in association with early Anglo-Saxon pottery.

  5. The Allergen Der p3 from House Dust Mite Stimulates Store-Operated Ca2+ Channels and Mast Cell Migration through PAR4 Receptors.

    Science.gov (United States)

    Lin, Yu-Ping; Nelson, Charmaine; Kramer, Holger; Parekh, Anant B

    2018-04-19

    The house dust mite is the principal source of perennial aeroallergens in man. How these allergens activate innate and adaptive immunity is unclear, and therefore, there are no therapies targeting mite allergens. Here, we show that house dust mite extract activates store-operated Ca 2+ channels, a common signaling module in numerous cell types in the lung. Activation of channel pore-forming Orai1 subunits by mite extract requires gating by STIM1 proteins. Although mite extract stimulates both protease-activated receptor type 2 (PAR2) and PAR4 receptors, Ca 2+ influx is more tightly coupled to the PAR4 pathway. We identify a major role for the serine protease allergen Der p3 in stimulating Orai1 channels and show that a therapy involving sub-maximal inhibition of both Der p3 and Orai1 channels suppresses mast cell activation to house dust mite. Our results reveal Der p3 as an important aeroallergen that activates Ca 2+ channels and suggest a therapeutic strategy for treating mite-induced asthma. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Wood Dust

    Science.gov (United States)

    Learn about wood dust, which can raise the risk of cancers of the paranasal sinuses and nasal cavity. High amounts of wood dust are produced in sawmills, and in the furniture-making, cabinet-making, and carpentry industries.

  7. Searching for late neolithic spinning bowls in the central Balkans

    Directory of Open Access Journals (Sweden)

    Svilar Marija M.

    2017-01-01

    Full Text Available Over the past twenty years, research on textile has received increasing attention in archaeology worldwide, providing new insights into one of the most important crafts in human history. In contrast, activities related to spinning and weaving in the Late Neolithic settlements in the Central Balkans have only be treated with cursory attention, which has resulted in nothing more than a set of general assumptions in archaeological literature. Though some progress has recently been made, investigations of textile in prehistoric contexts are still far from their full potential. The quest for spinning bowls in ceramic assemblages constitutes an important part of the given research, providing new evidence on the production of both textiles and pottery. Therefore, the focus of this paper is on the available evidence for those activities related to textile production in the Late Neolithic, primarily to spinning, with special emphasis on the earliest occurrence of spinning bowls in the Central Balkans i.e. the technology of wetting and tightening plant fibres in ceramic vessels.

  8. Characteristics of bowl-shaped coils for transcranial magnetic stimulation

    Science.gov (United States)

    Yamamoto, Keita; Suyama, Momoko; Takiyama, Yoshihiro; Kim, Dongmin; Saitoh, Youichi; Sekino, Masaki

    2015-05-01

    Transcranial magnetic stimulation (TMS) has recently been used as a method for the treatment of neurological and psychiatric diseases. Daily TMS sessions can provide continuous therapeutic effectiveness, and the installation of TMS systems at patients' homes has been proposed. A figure-eight coil, which is normally used for TMS therapy, induces a highly localized electric field; however, it is challenging to achieve accurate coil positioning above the targeted brain area using this coil. In this paper, a bowl-shaped coil for stimulating a localized but wider area of the brain is proposed. The coil's electromagnetic characteristics were analyzed using finite element methods, and the analysis showed that the bowl-shaped coil induced electric fields in a wider area of the brain model than a figure-eight coil. The expanded distribution of the electric field led to greater robustness of the coil to the coil-positioning error. To improve the efficiency of the coil, the relationship between individual coil design parameters and the resulting coil characteristics was numerically analyzed. It was concluded that lengthening the outer spherical radius and narrowing the width of the coil were effective methods for obtaining a more effective and more uniform distribution of the electric field.

  9. An Ecocritical Reading of Paul Bowles's The Sheltering Sky

    Directory of Open Access Journals (Sweden)

    Hossein Sheikhzadeh

    2017-07-01

    Full Text Available Landscapes are not simply something objective and unchallenged out there but the work of the mind made by the strata of memory. This paper attempts to show that an ecocritical reading of Paul Bowles’s The Sheltering Sky (1949 helps one in better understanding of this novel of post-colonial alienation and existential despair. Bowles is an American writer and a composer who is undoubtedly the most arresting example of cross-cultural influence concerning a Western author and the Middle East and North Africa.  His fiction mostly focuses on American expatriates travelling in exotic locations. The Sheltering Sky is an encounter with the Sahara, not only the physical one but the desert of moral nihilism into which one may wander blindly. The boundless desert acts here as a metaphor and the journey symbolizes one’s own journey into the depth of his/her soul. The desert also projects an apocalyptic vision in the struggle between the West and the East and the Sahara becomes in fact a Conradian Heart of Darkness, an Eliotian Waste Land, and a Sartrean No Exit. In the novel the actual environment becomes in some ways pale and covert under the psyche of the writer. Consequently we come to know that Bowles's own knowledge and awareness of the same environments left traces in his work. Accordingly we may wrap up that the environment bears a direct impact on our understanding of it.

  10. Larger Bowl Size Increases the Amount of Cereal Children Request, Consume, and Waste

    NARCIS (Netherlands)

    Wansink, Brian; van Ittersum, Koert; Payne, Collin R.

    Objective To examine whether larger bowls bias children toward requesting more food from the adults who serve them. Study design Study 1 was a between-subject design involving 69 preschool-age children who were randomized to receive either a small (8 oz) or large (16 oz) cereal bowl and were asked

  11. Children of the Harvest: The Schooling of Dust Bowl and Mexican Migrants during the Depression Era.

    Science.gov (United States)

    Theobald, Paul; Donato, Ruben

    1990-01-01

    Chronicles experiences of depression era "Okies," juxtaposes them against experiences of Mexican Americans, and illuminates the diminution of agricultural labor in an industrializing society. Schooling for those groups was legitimized by their low occupational status. When economic circumstances improved, whites escaped from migrant…

  12. Multiphase CFD simulation of a solid bowl centrifuge

    Energy Technology Data Exchange (ETDEWEB)

    Romani Fernandez, X.; Nirschl, H. [Universitaet Karlsruhe, Institut fuer MVM, Karlsruhe (Germany)

    2009-05-15

    This study presents some results from the numerical simulation of the flow in an industrial solid bowl centrifuge used for particle separation in industrial fluid processing. The computational fluid dynamics (CFD) software Fluent was used to simulate this multiphase flow. Simplified two-dimensional and three-dimensional geometries were built and meshed from the real centrifuge geometry. The CFD results show a boundary layer of axially fast moving fluid at the gas-liquid interface. Below this layer there is a thin recirculation. The obtained tangential velocity values are lower than the ones for the rigid-body motion. Also, the trajectories of the solid particles are evaluated. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  13. Double concave cesium encapsulation by two charged sumanenyl bowls

    Energy Technology Data Exchange (ETDEWEB)

    Spisak, Sarah N.; Wei, Zheng; Petrukhina, Marina A. [Department of Chemistry, University at Albany, State University of New York, Albany, NY (United States); Rogachev, Andrey Yu. [Department of Chemistry, Illinois Institute of Technology, Chicago, IL (United States); Amaya, Toru [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita (Japan); Hirao, Toshikazu [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita (Japan); The Institute of Scientific and Industrial Research, Osaka University (Japan)

    2017-03-01

    The controlled reaction of Na and Cs, two alkali metals of different ionic sizes and binding abilities, with sumanene (C{sub 21}H{sub 12}) affords a novel type of organometallic sandwich [Cs(C{sub 21}H{sub 11}{sup -}){sub 2}]{sup -}, which crystallized as a solvent-separated ion pair with a [Na(18-crown-6)(THF){sub 2}]{sup +} cation (where THF=tetrahydrofuran). The unprecedented double concave encapsulation of a metal ion by two bowl-shaped sumanenyl anions in [Cs(C{sub 21}H{sub 11}{sup -}){sub 2}]{sup -} was revealed crystallographically. Evaluation of bonding and energetics of the remarkable product was accomplished computationally (B2PLYP-D/TZVP/ZORA), providing insights into its formation. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Spatial patterns of bee captures in North American bowl trapping surveys

    Science.gov (United States)

    Droege, Sam; Tepedino, Vincent J.; Lebuhn, Gretchen; Link, William; Minckley, Robert L.; Chen, Qian; Conrad, Casey

    2010-01-01

    1. Bowl and pan traps are now commonly used to capture bees (Hymenoptera: Apiformes) for research and surveys. 2. Studies of how arrangement and spacing of bowl traps affect captures of bees are needed to increase the efficiency of this capture technique. 3. We present results from seven studies of bowl traps placed in trapping webs, grids, and transects in four North American ecoregions (Mid-Atlantic, Coastal California, Chihuahuan Desert, and Columbia Plateau). 4. Over 6000 specimens from 31 bee genera were captured and analysed across the studies. 5. Based on the results from trapping webs and distance tests, the per bowl capture rate of bees does not plateau until bowls are spaced 3–5 m apart. 6. Minor clumping of bee captures within transects was detected, with 26 of 56 transects having index of dispersion values that conform to a clumped distribution and 39 transects having positive Green's index values, 13 with zero, and only four negative. However, degree of clumping was slight with an average value of only 0.06 (the index ranges from -1 to 1) with only five values >0.15. Similarly, runs tests were significant for only 5.9% of the transects. 7. Results indicate that (i) capture rates are unaffected by short distances between bowls within transects and (ii) that bowls and transects should be dispersed throughout a study site.

  15. The effect of bowl-in-piston geometry layout on fluid flow pattern

    Directory of Open Access Journals (Sweden)

    Jovanovic Zoran S.

    2011-01-01

    Full Text Available In this paper some results concerning the evolution of 3D fluid flow pattern through all four strokes in combustion chambers with entirely different bowl-in-piston geometry layouts ranging from ”omega” to “simple cylinder” were presented. All combustion chambers i.e. those with „omega“ bowls, with different profiles, and those with „cylinder“ bowls, with different squish area ranging from 44% to 62%, were with flat head, vertical valves and identical elevation of intake and exhaust ports. A bunch of results emerged by dint of multidimensional modeling of nonreactive fluid flow in arbitrary geometry with moving objects and boundaries. The fluid flow pattern during induction and compression in all cases was extremely complicated and entirely three-dimensional. It should be noted that significant differences due to geometry of the bowl were encountered only in the vicinity of TDC. Namely, in the case of “omega” bowl all three types of organized macro flows were observed while in the case of “cylinder” bowl no circumferential velocity was registered at all. On the contrary, in the case of “cylinder” bowl some interesting results concerning reverse tumble and its center of rotation shifting from exhaust valve zone to intake valve zone during induction stroke and vice-verse from intake valve zone to exhaust valve zone during compression were observed while in the case of “omega” bowl no such a displacement was legible. During expansion the fluid flow pattern is fully controlled by piston motion and during exhaust it is mainly one-dimensional, except in the close proximity of exhaust valve. For that reason it is not affected by the geometry of the bowl.

  16. Cometary Dust

    Science.gov (United States)

    Levasseur-Regourd, Anny-Chantal; Agarwal, Jessica; Cottin, Hervé; Engrand, Cécile; Flynn, George; Fulle, Marco; Gombosi, Tamas; Langevin, Yves; Lasue, Jérémie; Mannel, Thurid; Merouane, Sihane; Poch, Olivier; Thomas, Nicolas; Westphal, Andrew

    2018-04-01

    This review presents our understanding of cometary dust at the end of 2017. For decades, insight about the dust ejected by nuclei of comets had stemmed from remote observations from Earth or Earth's orbit, and from flybys, including the samples of dust returned to Earth for laboratory studies by the Stardust return capsule. The long-duration Rosetta mission has recently provided a huge and unique amount of data, obtained using numerous instruments, including innovative dust instruments, over a wide range of distances from the Sun and from the nucleus. The diverse approaches available to study dust in comets, together with the related theoretical and experimental studies, provide evidence of the composition and physical properties of dust particles, e.g., the presence of a large fraction of carbon in macromolecules, and of aggregates on a wide range of scales. The results have opened vivid discussions on the variety of dust-release processes and on the diversity of dust properties in comets, as well as on the formation of cometary dust, and on its presence in the near-Earth interplanetary medium. These discussions stress the significance of future explorations as a way to decipher the formation and evolution of our Solar System.

  17. The development of a novel cricket bowling system: recreating spin and swing bowling deliveries at the elite level

    Science.gov (United States)

    West, A. A.; Justham, L.

    2008-03-01

    During the game of cricket, bowlers create different deliveries by altering the manner in which they release the ball from their hand. The orientation of the seam, the speed at which the ball is released and the magnitude and direction of the spin combine to determine the motion of the ball through the air and its movement after impact with the wicket. These factors have to be considered if automatic training machines are to be capable of replicating elite bowling deliveries. The need for automotive systems for batting and fielding training at the elite level has arisen due to: (i) the capabilities of human bowlers are limited by the onset of fatigue and the risk of injury and (ii) a large number of accurate and repeatable deliveries to be ''programmable'' by coaches to ensure batsmen and fielders are tested to the limits of their abilities and a training benefit is achieved.

  18. The preference for water nipples vs. water bowls in dairy goats

    Directory of Open Access Journals (Sweden)

    Andersen Inger L

    2011-09-01

    Full Text Available Abstract Background Previous studies have reported that the design of the water dispensers can influence the water intake in farm animals. Horses and dairy cows seem to prefer to drink from an open surface whereas sheep and pigs apparently prefer water nipples, probably because of the worse water quality in water bowls. The aim of the present study was to examine the preference of dairy goats for water nipples or water bowls. Methods In each of the two experiments (exp. 1, dry goats, exp. 2 lactating goats, 42 dairy goats were allotted into 6 groups of 7 goats. In period 1, the goats had access to a water nipple. In period 2, they had access to a water bowl and in period 3 (preference test they had access to both a water nipple and a water bowl. Water usage and wastage was recorded and water intake (water usage - water wastage was calculated for each group for the two last days of each period. In experiment 2, water samples from each dispenser were analyzed for heterotrophy germs at 22°C, Escherichia coli and turbidity. Results Water usage was higher from water nipples than from water bowls both in experiment 1 (dry goats and experiment 2 (lactating goats. There was however, no difference in water intake from water nipples and water bowls. In the preference test (period 3, the water intake tended to be higher from the water nipple than from the water bowl both for the dry goats (exp. 1 and lactating goats (exp. 2. Especially for the dry goats, the differences between groups were large. Turbidity and heterotrophy germs were much higher in the samples from the water bowls than from the water nipples. Water wastage from the water bowls was negligible compared to the water nipples. From the water nipples the water wastage was 30% and 23% of water usage for the dry and lactating goats respectively. Conclusions We conclude that type of water dispenser (nipple or bowl was probably of minor importance for water intake in goats, but water bowls had a

  19. Allergies, asthma, and dust

    Science.gov (United States)

    Reactive airway disease - dust; Bronchial asthma - dust; Triggers - dust ... Things that make allergies or asthma worse are called triggers. Dust is a common trigger. When your asthma or allergies become worse due to dust, you are ...

  20. A Bowl of Rice Too Far: The Burma Campaign of the Japanese Fifteen Army

    Science.gov (United States)

    2016-05-26

    A Bowl of Rice Too Far: The Burma Campaign of the Japanese Fifteenth Army A Monograph by MAJ Peter S...4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER A Bowl of Rice Too Far: The Burma Campaign of the Japanese Fifteenth Army Sb. GRANT NUMBER Sc. PROGRAM...is Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT In 1942 the Japanese Fifteenth Army overwhelmed the Allied forces defending Burma. However, in

  1. An integrated approach to the biomechanics and motor control of cricket fast bowling techniques.

    Science.gov (United States)

    Glazier, Paul S; Wheat, Jonathan S

    2014-01-01

    To date, scientific investigations into the biomechanical aspects of cricket fast bowling techniques have predominantly focused on identifying the mechanical factors that may predispose fast bowlers to lower back injury with a relative paucity of research being conducted on the technical features that underpin proficient fast bowling performance. In this review paper, we critique the scientific literature examining fast bowling performance. We argue that, although many published investigations have provided some useful insights into the biomechanical factors that contribute to a high ball release speed and, to a lesser extent, bowling accuracy, this research has not made a substantive contribution to knowledge enhancement and has only had a very minor influence on coaching practice. To significantly enhance understanding of cricket fast bowling techniques and, therefore, have greater impact on practice, we recommend that future scientific research adopts an interdisciplinary focus, integrating biomechanical measurements with the analytical tools and concepts of dynamical systems motor control theory. The use of qualitative (topological) analysis techniques, in particular, promises to increase understanding of the coordinative movement patterns that define 'technique' in cricket fast bowling and potentially help distinguish between functional and dysfunctional aspects of technique for individual fast bowlers.

  2. PRELIMINARY RESULTS OF BOWL TRAPPING BEES (HYMENOPTERA, APOIDEA IN A SOUTHERN BRAZIL FOREST FRAGMENT

    Directory of Open Access Journals (Sweden)

    Rodrigo B. Gonçalves

    2013-05-01

    Full Text Available In recent years bowl traps have gained attention as a useful method for sampling bees and are now commonly used across the world for this purpose. However, specific questions about the method itself have not yet been tested on different regions of the globe. We present the preliminary results of bowl trapping in a Semidecidual Seasonal forest fragment in southern Brazil, including the test of two different color bowls, two different habitats, and the interaction of these variables in bee species number and composition. We used blue and yellow bowls in the border and in the core trails of the forest fragment. In five sampling days between October to December bowl traps captured 745 specimens of 37 morphospecies, with Halictinae bees being the richest and most abundant group. Non parametrical statistical analyses suggested that different colors of bowl traps influenced bee richness and composition and thus, they should be used together for a more complete sampling. Different trails influenced only the composition, while the interaction with different colors did not have a significant effect. These results, as well as the higher taxonomic composition of the inventoried bees, are similar to other studies reported in the literature.

  3. Effect of Ball Weight on Speed, Accuracy, and Mechanics in Cricket Fast Bowling

    Directory of Open Access Journals (Sweden)

    Katharine L. Wickington

    2017-02-01

    Full Text Available The aims of this study were: (1 to quantify the acute effects of ball weight on ball release speed, accuracy, and mechanics in cricket fast bowling; and (2 to test whether a period of sustained training with underweight and overweight balls is effective in increasing a player’s ball release speed. Ten well-trained adult male cricket players performed maximum-effort deliveries using balls ranging in weight from 46% to 137% of the standard ball weight (156 g. A radar gun, bowling target, and 2D video analysis were used to obtain measures of ball speed, accuracy, and mechanics. The participants were assigned to either an intervention group, who trained with underweight and overweight balls, or to a control group, who trained with standard-weight balls. We found that ball speed decreased at a rate of about 1.1 m/s per 100 g increase in ball weight. Accuracy and bowling mechanics were not adversely affected by changes in ball weight. There was evidence that training with underweight and overweight balls might have produced a practically meaningful increase in bowling speed (>1.5 m/s in some players without compromising accuracy or increasing their risk of injury through inducing poor bowling mechanics. In cricket fast bowling, a wide range of ball weight might be necessary to produce an effective modified-implement training program.

  4. Sahara Dust Cloud

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Dust Particles Click on the image for Quicktime movie from 7/15-7/24 A continent-sized cloud of hot air and dust originating from the Sahara Desert crossed the Atlantic Ocean and headed towards Florida and the Caribbean. A Saharan Air Layer, or SAL, forms when dry air and dust rise from Africa's west coast and ride the trade winds above the Atlantic Ocean. These dust clouds are not uncommon, especially during the months of July and August. They start when weather patterns called tropical waves pick up dust from the desert in North Africa, carry it a couple of miles into the atmosphere and drift westward. In a sequence of images created by data acquired by the Earth-orbiting Atmospheric Infrared Sounder ranging from July 15 through July 24, we see the distribution of the cloud in the atmosphere as it swirls off of Africa and heads across the ocean to the west. Using the unique silicate spectral signatures of dust in the thermal infrared, AIRS can detect the presence of dust in the atmosphere day or night. This detection works best if there are no clouds present on top of the dust; when clouds are present, they can interfere with the signal, making it much harder to detect dust as in the case of July 24, 2005. In the Quicktime movie, the scale at the bottom of the images shows +1 for dust definitely detected, and ranges down to -1 for no dust detected. The plots are averaged over a number of AIRS observations falling within grid boxes, and so it is possible to obtain fractional numbers. [figure removed for brevity, see original site] Total Water Vapor in the Atmosphere Around the Dust Cloud Click on the image for Quicktime movie The dust cloud is contained within a dry adiabatic layer which originates over the Sahara Desert. This Saharan Air Layer (SAL) advances Westward over the Atlantic Ocean, overriding the cool, moist air nearer the surface. This burst of very dry air is visible in the AIRS retrieved total water

  5. Evaluation of American Indian Science and Engineering Society Intertribal Middle School Science and Math Bowl Project

    Energy Technology Data Exchange (ETDEWEB)

    AISES, None

    2013-09-25

    The American Indian Science and Engineering Society (AISES) has been funded under a U.S. Department of Energy (DOE) grant (Grant Award No. DE-SC0004058) to host an Intertribal Middle-School Science and Math Bowl (IMSSMB) comprised of teams made up of a majority of American Indian students from Bureau of Indian Education-funded schools and public schools. The intent of the AISES middle school science and math bowl is to increase participation of American Indian students at the DOE-sponsored National Science Bowl. Although national in its recruitment scope, the AISES Intertribal Science and Math Bowl is considered a “regional” science bowl, equivalent to the other 50 regional science bowls which are geographically limited to states. Most regional bowls do not have American Indian student teams competing, hence the AISES bowl is meant to encourage American Indian student teams to increase their science knowledge in order to participate at the national level. The AISES competition brings together teams from various American Indian communities across the nation. Each team is provided with funds for travel to and from the event, as well as for lodging and meals. In 2011 and 2012, there were 10 teams participating; in 2013, the number of teams participating doubled to 20. Each Science and Math Bowl team is comprised of four middle school — grades 6 through 8 — students, one alternate, and a teacher who serves as advisor and coach — although in at least two cases, the coach was not a teacher, but was the Indian Education Coordinator. Each team member must have at least a 3.0 GPA. Furthermore, the majority of students in each team must be comprised of American Indian, Alaska Native or Native Hawaiian students. Under the current DOE grant, AISES sponsored three annual middle school science bowl competitions over the years 2011, 2012 and 2013. The science and math bowls have been held in late March concurrently with the National American Indian Science and

  6. A numerical study on the effect of various combustion bowl parameters on the performance, combustion, and emission behavior on a single cylinder diesel engine.

    Science.gov (United States)

    Balasubramanian, Dhinesh; Sokkalingam Arumugam, Sabari Rajan; Subramani, Lingesan; Joshua Stephen Chellakumar, Isaac JoshuaRamesh Lalvani; Mani, Annamalai

    2018-01-01

    A numerical study was carried out to study the effect of various combustion bowl parameters on the performance behavior, combustion characteristics, and emission magnitude on a single cylinder diesel engine. A base combustion bowl and 11 different combustion bowls were created by varying the aspect ratio, reentrancy ratio, and bore to bowl ratio. The study was carried out at engine rated speed and a full throttle performance condition, without altering the compression ratio. The results revealed that the combustion bowl parameters could have a huge impact on the performance behavior, combustion characteristics, and emission magnitude of the engine. The bowl parameters, namely throat diameter and toroidal radius, played a crucial role in determining the performance behavior of the combustion bowls. It was observed that the combustion bowl parameters, namely central pip distance, throat diameter, and bowl depth, also could have an impact on the combustion characteristics. And throat diameter and toroidal radius, central pip distance, and toroidal corner radius could have a consequent effect on the emission magnitude of the engine. Of the different combustion bowls tested, combustion bowl 4 was preferable to others owing to the superior performance of 3% of higher indicated mean effective pressure and lower fuel consumption. Interestingly, trade-off for NO x emission was higher only by 2.85% compared with the base bowl. The sensitivity analysis proved that bowl depth, bowl diameter, toroidal radius, and throat diameter played a vital role in the fuel consumption parameter and emission characteristics even at the manufacturing tolerance variations.

  7. Lumbar spinal loading during bowling in cricket: a kinetic analysis using a musculoskeletal modelling approach.

    Science.gov (United States)

    Zhang, Yanxin; Ma, Ye; Liu, Guangyu

    2016-01-01

    The objective of the study was to evaluate two types of cricket bowling techniques by comparing the lumbar spinal loading using a musculoskeletal modelling approach. Three-dimensional kinematic data were recorded by a Vicon motion capture system under two cricket bowling conditions: (1) participants bowled at their absolute maximal speeds (max condition), and (2) participants bowled at their absolute maximal speeds while simultaneously forcing their navel down towards their thighs starting just prior to ball release (max-trunk condition). A three-dimensional musculoskeletal model comprised of the pelvis, sacrum, lumbar vertebrae and torso segments, which enabled the motion of the individual lumbar vertebrae in the sagittal, frontal and coronal planes to be actuated by 210 muscle-tendon units, was used to simulate spinal loading based on the recorded kinematic data. The maximal lumbar spine compressive force is 4.89 ± 0.88BW for the max condition and 4.58 ± 0.54BW for the max-trunk condition. Results showed that there was no significant difference between the two techniques in trunk moments and lumbar spine forces. This indicates that the max-trunk technique may not increase lower back injury risks. The method proposed in this study could be served as a tool to evaluate lower back injury risks for cricket bowling as well as other throwing activities.

  8. Neutron activation analysis of bird bowls and related archaic ceramics from Miletus

    International Nuclear Information System (INIS)

    Kerschner, M.; Mommsen, H.; Beier, T.; Heimermann, D.; Hein, A.

    1993-01-01

    In this paper we present the results of a chemical investigation by neutron activation analysis of sherds of different kinds of bird kotylai, bird bowls and related wares excavated in Kalabaktepe, a hill of the ancient city of Miletus. A new archaeological classification of this well-known group of Archaic ceramics of eastern Greece is presented. A number of kiln wasters of misfired vessels from Kalabaktepe revealed a characteristic local pattern. This pattern helped to clarify the provenance of some of the bird bowls classified archaeologically as of orientalizing type: they have been made in Miletus. But bird kotylai and bird bowls in the ''standard fabric'' as well as other archaeologically related vessels show a different chemical pattern of unknown provenance. (author)

  9. Neutron activation analysis of bird bowls and related archaic ceramics from Miletus

    International Nuclear Information System (INIS)

    Kerschner, M.; Mommsen, H.; Beier, T.; Heimermann, D.; Hein, A.

    1993-01-01

    In this paper we present the results of a chemical investigation by neutron activation analysis of sherds of different kinds of bird kotylai, bird bowls and related wares excavated in Kalabaktepe, a hill of the ancient city of Miletus. A new archaeological classification of this well-known group of Archaic ceramics of eastern Greece is represented. A number of kiln wasters of misfired vessels from Kalabaktepe revealed a characteristic local pattern. This pattern helped to clarify the provenance of some of the bird bowls classified archaeologically as of orientalizing type: they have been made in Miletus. But bird kotylai and bird bowls in the 'standard fabric' as well as other archaeologically related vessels show a different chemical pattern of unknown provenance. (author)

  10. DAMPAK PERMAINAN BOWLING TIRUAN TERHADAP KECAKAPAN MOTORIK ANAK TERBELAKANG MENTAL USIA DINI

    Directory of Open Access Journals (Sweden)

    Suparno -

    2014-06-01

    Abstrak: Dampak Permainan Bowling Tiruan terhadap Keterampilan Motorik Anak Terbelakang Mental Usia Dini. Penelitian ini bertujuan untuk memperoleh gambaran mengenai dampak permainan dengan aturan bowling tiruan terhadap peningkatan kecakapan koordinasi motorik anak terbelakang mental usia dini. Sebanyak enam anak yang mengalami keterbelakangan mental berusia 5-7 tahun, terdiri atas empat laki-laki dan dua wanita di TKLB/C Pembina Yogyakarta yang diambil secara purposive dijadikan subjek. Penelitian ini merupakan penelitian kuasi eksperimen dengan rancangan pretes-postes satu kelompok. Observasi terbuka dan rekaman video digunakan untuk melihat kecakapan koordinasi motorik subjek. Hasil penelitian menunjukkan adanya dampak positif permainan dengan aturan berupa bowling tiruan terhadap peningkatan kecakapan koordinasi motorik anak terbelakang mental usia dini.

  11. Studies on piston bowl geometries using single blend ratio of various non-edible oils.

    Science.gov (United States)

    Viswanathan, Karthickeyan; Pasupathy, Balamurugan

    2017-07-01

    The depletion of fossil fuels and hike in crude oil prices were some of the main reasons to explore new alternatives from renewable source of energy. This work presents the impact of various bowl geometries on diesel engine with diesel and biodiesel samples. Three non-edible oils were selected, namely pumpkin seed oil, orange oil and neem oil. These oils were converted into respective biodiesel using transesterification process in the presence of catalyst and alcohol. After transesterification process, the oils were termed as pumpkin seed oil methyl ester (PSOME), orange oil methyl ester (OME) and neem oil methyl ester (NOME), respectively. The engine used for experimentation was a single-cylinder four-stroke water-cooled direct-injection diesel engine and loads were applied to the engine using eddy current dynamometer. Two bowl geometries were developed, namely toroidal combustion chamber (TCC) and trapezoidal combustion chamber (TRCC). Also, the engine was inbuilt with hemispherical combustion chamber (HCC). The base line readings were recorded using neat diesel fuel with HCC for various loads. Followed by 20% of biodiesel mixed with 80% neat diesel for all prepared methyl esters and termed as B1 (20% PSOME with 80% diesel), B2 (20% OME with 80% diesel) and B3 (20% NOME with 80% diesel). All fuel samples were tested in HCC, TCC and TRCC bowl geometries under standard injection timing and with compression ratio of 18. Increased brake thermal efficiency and reduced brake specific fuel consumption were observed with diesel in TCC geometry. Also, higher heat release and cylinder pressures with lower ignition delay were recorded with TCC bowl geometry. TCC bowl geometry showed lower CO, HC and smoke emissions with B2 fuel sample than diesel and other biodiesel samples. But, higher NOx emission was observed in HCC and TCC than that in TRCC bowl geometry. Graphical abstract ᅟ.

  12. The preference for water nipples vs. water bowls in dairy goats

    OpenAIRE

    B?e, Knut E; Ehrlenbruch, Rebecca; Andersen, Inger L

    2011-01-01

    Abstract Background Previous studies have reported that the design of the water dispensers can influence the water intake in farm animals. Horses and dairy cows seem to prefer to drink from an open surface whereas sheep and pigs apparently prefer water nipples, probably because of the worse water quality in water bowls. The aim of the present study was to examine the preference of dairy goats for water nipples or water bowls. Methods In each of the two experiments (exp. 1, dry goats, exp. 2 l...

  13. ENVIRONMENTAL TECHNOLOGY VERIFICATION: JOINT (NSF-EPA) VERIFICATION STATEMENT AND REPORT: TRITON SYSTEMS, LLC SOLID BOWL CENTRIFUGE, MODEL TS-5000

    Science.gov (United States)

    Verification testing of the Triton Systems, LLC Solid Bowl Centrifuge Model TS-5000 (TS-5000) was conducted at the Lake Wheeler Road Field Laboratory Swine Educational Unit in Raleigh, North Carolina. The TS-5000 was 48" in diameter and 30" deep, with a bowl capacity of 16 ft3. ...

  14. Does Becoming a Member of the Football Bowl Subdivision Increase Institutional Attractiveness to Potential Students

    Science.gov (United States)

    Jones, Willis A.

    2014-01-01

    In recent years, a number of colleges and universities have made the decision to pursue membership in the NCAA's Football Bowl Subdivision (FBS) with the idea that participating in higher profile intercollegiate football can help attract students to their institution. This belief, however, has not been empirically examined. Using…

  15. Reclassification to the NCAA Division I Football Bowl Subdivision: A Case Study at Western Kentucky University

    Science.gov (United States)

    Upright, Paula A.

    2009-01-01

    The purpose of this study was to describe the reclassification process of Western Kentucky University's football program from the Football Championship Subdivision (FCS) to the Football Bowl Subdivision (FBS), the highest and most visible level of NCAA competition. Three research questions guided the study: (a) Why did Western Kentucky University…

  16. Finishes for Wood Bowls, Butcher Blocks, Other Items Used for Food, and Children's Toys

    Science.gov (United States)

    Mark T. Knaebe

    2013-01-01

    The durability and beauty of wood make it an attractive material for bowls, butcher blocks, and other items used to serve or prepare food. Wood also tends to be less prone to harbor bacteria than are some other materials such as plastic.

  17. The kinematic differences between off-spin and leg-spin bowling in cricket.

    Science.gov (United States)

    Beach, Aaron J; Ferdinands, René E D; Sinclair, Peter J

    2016-09-01

    Spin bowling is generally coached using a standard technical framework, but this practice has not been based upon a comparative biomechanical analysis of leg-spin and off-spin bowling. This study analysed the three-dimensional (3D) kinematics of 23 off-spin and 20 leg-spin bowlers using a Cortex motion analysis system to identify how aspects of the respective techniques differed. A multivariate ANOVA found that certain data tended to validate some of the stated differences in the coaching literature. Off-spin bowlers had a significantly shorter stride length (p = 0.006) and spin rate (p = 0.001), but a greater release height than leg-spinners (p = 0.007). In addition, a number of other kinematic differences were identified that were not previously documented in coaching literature. These included a larger rear knee flexion (p = 0.007), faster approach speed (p < 0.001), and flexing elbow action during the arm acceleration compared with an extension action used by most of the off-spin bowlers. Off-spin and leg-spin bowlers also deviated from the standard coaching model for the shoulder alignment, front knee angle at release, and forearm mechanics. This study suggests that off-spin and leg-spin are distinct bowling techniques, supporting the development of two different coaching models in spin bowling.

  18. Feeling objects in Virtual Environments: Presence and Pseudo-Haptics in a Bowling Game

    DEFF Research Database (Denmark)

    Daniliauskaite, Kristina; Magnusdottir, Agusta; Bjørkå, Henrik Birke

    2007-01-01

    , by relying on visual cues, taking therefore advantage of sensory substitution (no haptic feedback device is actually present). The interdependency between presence and a pseudo-haptic feedback is investigated by building avirtual bowling game. Results indicate that there is a significant correlation between...

  19. Elderly people's perceptions of using Wii sports bowling - A qualitative study.

    Science.gov (United States)

    Glännfjord, Fredrik; Hemmingsson, Helena; Larsson Ranada, Åsa

    2017-09-01

    The Nintendo Wii is a gaming console with motion-sensitive controls that is making inroads into health care and rehabilitation. However, there is still limited knowledge on how elderly people perceive the use of such a product. The aim of this study was to examine how the use of the Wii Sports Bowling in an activity group was perceived by elderly people. The data consisted of observations and interviews with participants who used Wii Sports Bowling and was analysed with content analysis. The findings are described in three themes; 'The use of the Wii Sports game', 'Engagement in the game' and 'Social interaction around the activity'. Wii Sports Bowling was described as easier to play compared to real-life bowling and was enjoyable and a social activity. The opportunity to meet the group each week was important for the participants. Playing the game resulted in signs of immersion and a flow-like state. The Wii was perceived to be easy to use, to provide a way to socialize with peers and to give opportunities to participate in activities in a new way. More studies regarding elderly people's experiences and apprehensions regarding new technology such as gaming consoles and virtual reality are needed.

  20. Research brief : Serving Bowl Selection Biases the Amount of Food Served

    NARCIS (Netherlands)

    Kleef, van E.; Shimizu, M.; Wansink, B.

    2012-01-01

    Objective: To determine how common serving bowls containing food for multiple persons influence serving behavior and consumption and whether they do so independently of satiation and food evaluation. Methods: In this between-subjects experiment, 68 participants were randomly assigned to either a

  1. Selling College: A Longitudinal Study of American College Football Bowl Game Public Service Announcements

    Science.gov (United States)

    Tobolowsky, Barbara F.; Lowery, John Wesley

    2014-01-01

    Using ideological analysis as a frame, researchers analyzed institutionally created commercials (PSAs) that appeared in 28 U.S. college football bowl games over a seven-year period (2003-2009) to better understand the universities' brands as represented in these advertisements. They found many common elements such as showing traditional…

  2. Phreatic explosions during basaltic fissure eruptions: Kings Bowl lava field, Snake River Plain, USA

    Science.gov (United States)

    Hughes, Scott S.; Kobs Nawotniak, Shannon E.; Sears, Derek W. G.; Borg, Christian; Garry, William Brent; Christiansen, Eric H.; Haberle, Christopher W.; Lim, Darlene S. S.; Heldmann, Jennifer L.

    2018-02-01

    Physical and compositional measurements are made at the 7 km-long ( 2200 years B.P.) Kings Bowl basaltic fissure system and surrounding lava field in order to further understand the interaction of fissure-fed lavas with phreatic explosive events. These assessments are intended to elucidate the cause and potential for hazards associated with phreatic phases that occur during basaltic fissure eruptions. In the present paper we focus on a general understanding of the geological history of the site. We utilize geospatial analysis of lava surfaces, lithologic and geochemical signatures of lava flows and explosively ejected blocks, and surveys via ground observation and remote sensing. Lithologic and geochemical signatures readily distinguish between Kings Bowl and underlying pre-Kings Bowl lava flows, both of which comprise phreatic ejecta from the Kings Bowl fissure. These basalt types, as well as neighboring lava flows from the contemporaneous Wapi lava field and the older Inferno Chasm vent and outflow channel, fall compositionally within the framework of eastern Snake River Plain olivine tholeiites. Total volume of lava in the Kings Bowl field is estimated to be 0.0125 km3, compared to a previous estimate of 0.005 km3. The main (central) lava lake lost a total of 0.0018 km3 of magma by either drain-back into the fissure system or breakout flows from breached levees. Phreatic explosions along the Kings Bowl fissure system occurred after magma supply was cut off, leading to fissure evacuation, and were triggered by magma withdrawal. The fissure system produced multiple phreatic explosions and the main pit is accompanied by others that occur as subordinate pits and linear blast corridors along the fissure. The drop in magma supply and the concomitant influx of groundwater were necessary processes that led to the formation of Kings Bowl and other pits along the fissure. A conceptual model is presented that has relevance to the broader range of low-volume, monogenetic

  3. The Importance of a Conchal Bowl Element in the Fabrication of a Three-Dimensional Framework in Total Auricular Reconstruction

    Directory of Open Access Journals (Sweden)

    Young Soo Kim

    2013-05-01

    Full Text Available BackgroundTo construct a sophisticated three-dimensional framework, numerous modifications have been reported in the literature. However, most surgeons have paid little attention to the anatomical configuration of the concha and more to its deepness and hollowness, leading to unsatisfactory outcomes.MethodsFor a configuration of the concha that is definitely anatomical, the author further developed and employed the conchal bowl element, which has been used by several surgeons although the results have not been published elsewhere. The author constructed the conchal bowl element in one of three patterns according to the amount of available cartilages: one block, two-pieces, or a cymba bowl element only. A total of 20 patients underwent auricular reconstruction using a costal cartilage framework between 2009 and 2012. The 8 earliest reconstructions were performed without a conchal bowl element and the latter 12 with a conchal bowl element. The patients were followed up for more than 1 year. The aesthetic results were scored by evaluating characteristics involving the stability of the crus helicis, the conchal definition, and the smoothness of the helical curve.ResultsThe ears reconstructed early without a conchal bowl element showed a shallow and one or two incompletely separated concha with an obliterated cymba conchal space. They also did not have a realistic or smooth curve of the helix because of an unstable crus helicis. However, ears reconstructed later with the concha bowl element showed a definite crus helicis, deep cymba conchal space, and smooth helical curve.ConclusionsThe construction of the conchal bowl element is simple, not time-consuming procedure. It is suggested that the conchal bowl element must be constructed and attached to the main framework for natural configuration of the reconstructed ear.

  4. Elastic–plastic adhesive impacts of tungsten dust with metal surfaces in plasma environments

    NARCIS (Netherlands)

    Ratynskaia, S.; Tolias, P.; Shalpegin, A.; Vignitchouk, L.; de Angeli, M.; I. Bykov,; Bystrov, K.; Bardin, S.; Brochard, F.; Ripamonti, D.; N. den Harder,; De Temmerman, G.

    2015-01-01

    Dust-surface collisions impose size selectivity on the ability of dust grains to migrate in scrape-off layer and divertor plasmas and to adhere to plasma-facing components. Here, we report first experimental evidence of dust impact phenomena in plasma environments concerning low-speed collisions of

  5. Dust Studies in DIII-D and TEXTOR

    International Nuclear Information System (INIS)

    Rudakov, D.L.; Litnovsky, A.; West, W.P.; Yu, J.H.; Boedo, J.A.; Bray, B.D.; Brezinsek, S.; Brooks, N.H.; Fenstermacher, M.E.; Groth, M.; Hollmann, E.M.; Huber, A.; Hyatt, A.W.; Krasheninnikov, S.I.; Lasnier, C.J.; Moyer, R.A.; Pigarov, A.Y.; Philipps, V.; Pospieszczyk, A.; Smirnov, R.D.; Sharpe, J.P.; Solomon, W.M.; Watkins, J.G.; Wong, C.C.

    2009-01-01

    Studies of naturally occurring and artificially introduced carbon dust are conducted in DIII-D and TEXTOR. In DIII-D, dust does not present operational concerns except immediately after entry vents. Submicron sized dust is routinely observed using Mie scattering from a Nd:Yag laser. The source is strongly correlated with the presence of Type I edge localized modes (ELMs). Larger size (0.005-1 mm diameter) dust is observed by optical imaging, showing elevated dust levels after entry vents. Inverse dependence of the dust velocity on the inferred dust size is found from the imaging data. Direct heating of the dust particles by the neutral beam injection (NBI) and acceleration of dust particles by the plasma flows are observed. Energetic plasma disruptions produce significant amounts of dust. Large flakes or debris falling into the plasma may result in a disruption. Migration of pre-characterized carbon dust is studied in DIII-D and TEXTOR by introducing micron-size dust in plasma discharges. In DIII-D, a sample holder filled with ∼30 mg of dust is introduced in the lower divertor and exposed to high-power ELMing H-mode discharges with strike points swept across the divertor floor. After a brief exposure (∼0.1 s) at the outer strike point, part of the dust is injected into the plasma, raising the core carbon density by a factor of 2-3 and resulting in a twofold increase of the radiated power. In TEXTOR, instrumented dust holders with 1-45 mg of dust are exposed in the scrape-off layer 0-2 cm radially outside of the last closed flux surface in discharges heated with neutral beam injection (NBI) power of 1.4 MW. At the given configuration of the launch, the dust did not penetrate the core plasma and only moderately perturbed the edge plasma, as evidenced by an increase of the edge carbon content.

  6. Preliminary Research on Granulation Process of Dust Waste from Reclamation Process of Moulding Sands with Furan Resin

    Directory of Open Access Journals (Sweden)

    J. Kamińska

    2012-09-01

    Full Text Available The results of investigations of the granulation process of foundry dusts generated in the dry mechanical reclamation process of usedsands, where furan resins were binders are presented in the paper. Investigations concerned producing of granules of the determineddimensions and strength parameters.Granules were formed from the dusts mixture consisting in 50 mass% of dusts obtained after the reclamation of the furane sands and in50 mass % of dusts from sands with bentonite. Dusts from the bentonite sands with water were used as a binder allowing the granulation of after reclamation dusts from the furane sands.The following parameters of the ready final product were determined: moisture content (W, shatter test of granules (Wz performeddirectly after the granulation process and after 1, 3, 5, 10 days and nights of seasoning, water-resistance of granules after 24 hours of being immersed in water, surface porosity ep and volumetric porosity ev. In addition the shatter test and water-resistance of granulate dried at a temperature of 105oC were determined.Investigations were performed at the bowl angle of inclination 45o, for three rotational speeds of the bowl being: 10, 15, 20 rpm.For the speed of 10 rpm the granulation tests of dusts mixture after the preliminary mixing in the roller mixer and with the addition ofwater-glass in the amount of 2% in relation to the amount of dust were carried out.The obtained results indicate that the granulator allows to obtain granules from dusts originated from the reclamations of mouldingsands with the furane resin with an addition of dusts from the bentonite sands processing plants.

  7. Dust collector

    Energy Technology Data Exchange (ETDEWEB)

    Sahourin, H.

    1988-03-22

    This invention relates to a dust collector or filter which may be used for large volume cleaning air for gases or for separating out industrial byproducts such as wood chips, sawdust, and shavings. It relies on filtration or separation using only a uniquely configured medium. A primary, but not exclusive, purpose of the invention is to enable very large throughput, capable of separating or filtering of gases containing up to three or more tons of byproduct with a minimum pressure-drop across the device. No preliminary cycloning, to remove major particulates is necessary. The collector generally comprises a continuous and integral filter medium which is suspended from a plurality of downwardly extending frames forming a series of separate elements having a triangular cross-section, each element being relatively wide at the top and narrow at the bottom to define, between adjacent elements, a divergent collecting space which is wide at the bottom. 11 figs.

  8. Dust Measurements in Tokamaks

    International Nuclear Information System (INIS)

    Rudakov, D; Yu, J; Boedo, J; Hollmann, E; Krasheninnikov, S; Moyer, R; Muller, S; Yu, A; Rosenberg, M; Smirnov, R; West, W; Boivin, R; Bray, B; Brooks, N; Hyatt, A; Wong, C; Fenstermacher, M; Groth, M; Lasnier, C; McLean, A; Stangeby, P; Ratynskaia, S; Roquemore, A; Skinner, C; Solomon, W M

    2008-01-01

    Dust production and accumulation impose safety and operational concerns for ITER. Diagnostics to monitor dust levels in the plasma as well as in-vessel dust inventory are currently being tested in a few tokamaks. Dust accumulation in ITER is likely to occur in hidden areas, e.g. between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In DIII-D tokamak dust diagnostics include Mie scattering from Nd:YAG lasers, visible imaging, and spectroscopy. Laser scattering resolves size of particles between 0.16-1.6 (micro)m in diameter; the total dust content in the edge plasmas and trends in the dust production rates within this size range have been established. Individual dust particles are observed by visible imaging using fast-framing cameras, detecting dust particles of a few microns in diameter and larger. Dust velocities and trajectories can be determined in 2D with a single camera or 3D using multiple cameras, but determination of particle size is problematic. In order to calibrate diagnostics and benchmark dust dynamics modeling, pre-characterized carbon dust has been injected into the lower divertor of DIII-D. Injected dust is seen by cameras, and spectroscopic diagnostics observe an increase of carbon atomic, C2 dimer, and thermal continuum emissions from the injected dust. The latter observation can be used in the design of novel dust survey diagnostics

  9. A Numerical Study of the Impact of Radial Baffles in solid Bowl Centrifuges Using computational Fluid Dynamics

    OpenAIRE

    Romani, Xiana; Nirschl, Hermann

    2010-01-01

    Centrifugal separation equipment, such as solid bowl centrifuges, is used to carry out an effective separation of fine particles from industrial fluids. Knowledge of the streams and sedimentation behavior inside solid bowl centrifuges is necessary to determine the geometry and the process parameters that lead to an optimal performance. Regarding a given industrial centrifuge geometry, a grid was built to calculate numerically the multiphase flow of water, air, and particles with a computation...

  10. Migration of formaldehyde and melamine monomers from kitchen- and tableware made of melamine plastic

    DEFF Research Database (Denmark)

    Lund, K.H.; Petersen, J.H.

    2006-01-01

    Migration of one or both formaldehyde and/or melamine monomers was found in seven of ten tested melamine samples bought on the Danish market. The samples were a bowl, a jug, a mug, a ladle, and different cups and plates. No violation of the European Union-specific migration limits for melamine (30...... mg kg(-1)) and formaldehyde (15 mg kg(-1)) was found after three successive exposures to the food stimulant 3% acetic acid after 2 h at 70 degrees C. To investigate the effects of long-term use, migration tests were performed with two types of cups from a day nursery. Furthermore, medium-term use...

  11. Effect of radiation on preservation of convenient dish 'bowl-shape packed pig elbow'

    International Nuclear Information System (INIS)

    Wang Keqin; Chen Jingping; Li Wenge; Peng Weizheng

    2005-01-01

    The suitable parameters for radiation processing were investiqated by analyzing the microload of material and product, and radiation effect on the preservation of convenient dish 'bowl-shape packed pig elbow'. The results showed the store period of the product could be extended 2-6 month by 4.0-6.0 kGy radiation at different storage temperature. The sensory, physical and chemical index of the products met the requirement of relevant national standard of food hygiene. (authors)

  12. Reduction of activity concentration of radiocesium in meat by preparation of heat-pressure bowling

    International Nuclear Information System (INIS)

    Dvorak, P.; Kunova, V.

    2006-01-01

    The meat (Sus stroma) was salted (5 g NaCl to 100 g meat) before preparation by heat pressure bowling - 15 minutes. There was reached drop of activity concentration of radiocesium about 50 % (from 42.7 % to 58.3 %). The meat had activity concentration of radiocesium 106 Bq · kg -1 . The activity concentration of radiocesium was reduced on average to 53 Bq · kg -1 . The activity concentration of 137 Cs was measured by gamma-spectrometry. (authors)

  13. Proyecto de creación de un bowling center en la ciudad de Milagro

    OpenAIRE

    Aviles, Miguel; Caluqui, Juliana; Pallazhco, Jenny; Tobalina, Constantino

    2010-01-01

    The Project realize an analysis the Bowling Center principal characteristic in Milagro City, also realized a study on the market for identify important aspect the production and demand, also realized a finance and economic analysis for demonstrate that yes or no is rental and plan the strategies for establishment the business and have a good result on de market, realized a camp investigation with which was confirmation the enterprise’s number that realize the same business, construction and t...

  14. Consistency of kinematic and kinetic patterns during a prolonged spell of cricket fast bowling: an exploratory laboratory study.

    Science.gov (United States)

    Schaefer, Andrew; O'dwyer, Nicholas; Ferdinands, René E D; Edwards, Suzi

    2018-03-01

    Due to the high incidence of lumbar spine injury in fast bowlers, international cricket organisations advocate limits on workload for bowlers under 19 years of age in training/matches. The purpose of this study was to determine whether significant changes in either fast bowling technique or movement variability could be detected throughout a 10-over bowling spell that exceeded the recommended limit. Twenty-five junior male fast bowlers bowled at competition pace while three-dimensional kinematic and kinetic data were collected for the leading leg, trunk and bowling arm. Separate analyses for the mean and within-participant standard deviation of each variable were performed using repeated measures factorial analyses of variance and computation of effect sizes. No substantial changes were observed in mean values or variability of any kinematic, kinetic or performance variables, which instead revealed a high degree of consistency in kinematic and kinetic patterns. Therefore, the suggestion that exceeding the workload limit per spell causes technique- and loading-related changes associated with lumbar injury risk is not valid and cannot be used to justify the restriction of bowling workload. For injury prevention, the focus instead should be on the long-term effect of repeated spells and on the fast bowling technique itself.

  15. "I only watch for the commercials": Messages about weight, eating and race in Super Bowl advertisements.

    Science.gov (United States)

    Lydecker, Janet A; Izzo, Antonio; Spielberger, Gail; Grilo, Carlos M

    2017-11-01

    Health experts and communication experts assert that the media influence individuals' health. Yet, incongruously, the public, policy-makers and the media themselves appear reticent to accept that the media could have extensive negative influence on health. The current study examined all ads that aired from Super Bowl XLVI through Super Bowl XLIX (N = 241) using a detailed, multistep coding process. Ads had similar racial/ethnic diversity in the full sample and food/beverage ads. A minority (14.5%) of advertisements contained actors with overweight/obesity, who were more likely to be White and less likely to be Hispanic compared with race/ethnicity in all ads. Humour and tone were similarly present whether or not the ads included actors with overweight/obesity. Findings are striking given the high prevalence of overweight/obesity in the USA, particularly among Black and Hispanic populations, and the comparatively low representation of actors with overweight/obesity in Super Bowl advertisements. Surprising weight findings may signal a change in how the media portray body-size norms (away from exclusively thin), although representations remain disproportionate from actual body-size distributions in the USA. © 2017 John Wiley & Sons Ltd.

  16. Elastic–plastic adhesive impacts of tungsten dust with metal surfaces in plasma environments

    Energy Technology Data Exchange (ETDEWEB)

    Ratynskaia, S., E-mail: svetlana.ratynskaia@ee.kth.se [KTH Royal Institute of Technology, Association EUROfusion-VR, Stockholm (Sweden); Tolias, P. [KTH Royal Institute of Technology, Association EUROfusion-VR, Stockholm (Sweden); Shalpegin, A. [Université de Lorraine, Institut Jean Lamour, Vandoeuvre-lès-Nancy (France); Vignitchouk, L. [KTH Royal Institute of Technology, Association EUROfusion-VR, Stockholm (Sweden); De Angeli, M. [Istituto di Fisica del Plasma – Consiglio Nazionale delle Ricerche, Milan (Italy); Bykov, I. [KTH Royal Institute of Technology, Association EUROfusion-VR, Stockholm (Sweden); Bystrov, K.; Bardin, S. [FOM Institute DIFFER, Dutch Institute For Fundamental Energy Research, Edisonbaan 14, 3439MN Nieuwegein (Netherlands); Brochard, F. [Université de Lorraine, Institut Jean Lamour, Vandoeuvre-lès-Nancy (France); Ripamonti, D. [Istituto per l’Energetica e le Interfasi – Consiglio Nazionale delle Ricerche, Milan (Italy); Harder, N. den; De Temmerman, G. [FOM Institute DIFFER, Dutch Institute For Fundamental Energy Research, Edisonbaan 14, 3439MN Nieuwegein (Netherlands)

    2015-08-15

    Dust-surface collisions impose size selectivity on the ability of dust grains to migrate in scrape-off layer and divertor plasmas and to adhere to plasma-facing components. Here, we report first experimental evidence of dust impact phenomena in plasma environments concerning low-speed collisions of tungsten dust with tungsten surfaces: re-bouncing, adhesion, sliding and rolling. The results comply with the predictions of the model of elastic-perfectly plastic adhesive spheres employed in the dust dynamics code MIGRAINe for sub- to several meters per second impacts of micrometer-range metal dust.

  17. The Importance of a Conchal Bowl Element in the Fabrication of a Three-Dimensional Framework in Total Auricular Reconstruction

    Directory of Open Access Journals (Sweden)

    Young Soo Kim

    2013-05-01

    Full Text Available Background  To construct a sophisticated three-dimensionalframework, numerousmodifications have been reported in the literature. However, mostsurgeons have paid little attentionto the anatomical configuration of the concha and more to its deepness and hollowness,leading to unsatisfactory outcomes.Methods  For a configuration ofthe concha thatis definitely anatomical,the authorfurtherdeveloped and employed the conchal bowl element,which has been used by severalsurgeonsalthough the results have not been published elsewhere. The author constructed the conchalbowl element in one of three patterns according to the amount of available cartilages: oneblock,two-pieces, or a cymba bowl element only. A total of 20 patients underwent auricularreconstruction using a costal cartilage framework between 2009 and 2012. The 8 earliestreconstructionswere performedwithout a conchal bowl element and the latter 12with a conchalbowl element. The patientswere followed up for more than 1 year. The aesthetic resultswerescored by evaluating characteristicsinvolving the stability ofthe crus helicis,the conchal definition, and the smoothness ofthe helical curve.Results  The earsreconstructed earlywithout a conchal bowl elementshowed a shallowandone or two incompletely separated concha with an obliterated cymba conchal space. Theyalso did not have a realistic orsmooth curve ofthe helix because of an unstable crus helicis.However, earsreconstructed laterwith the concha bowl elementshowed a definite crus helicis,deep cymba conchalspace, and smooth helical curve.Conclusions  The construction of the conchal bowl element is simple, not time-consumingprocedure. It is suggested that the conchal bowl element must be constructed and attachedto themain framework for natural configuration ofthe reconstructed ear.

  18. Investigation of the selected properties of dusts from the reclamation of spent sands with bentonite

    Directory of Open Access Journals (Sweden)

    J. Kamińska

    2011-10-01

    Full Text Available The investigation results of the selected properties of dusts generated during the mechanical reclamation of spent sands with bentonite as well as dusts from the dedusting system of sand processing plant are presented in the hereby paper. Investigations were performed with regard to determination conditions allowing to pelletise dusts in the bowl granulator. The verified methods of testing physical and chemical dust properties such as: specific density, bulk density of loosely put materials and apparent density of compacted materials together with their corresponding porosity, ignition losses and pH values, were applied. Granular composition of dusts generated during abrasion of spent binding materials in mechanical dry reclamation processes of spent sands with bentonite and coal dusts were performed by the laser diffraction analysis, allowing to broaden the measuring range of particle diameters. The optimal wetting agent content (in this case water at which the dust-water mixture obtains the best strength properties – after compacting by means of the standard moulder’s rammer – was determined.

  19. Climate change and climate systems influence and control the atmospheric dispersion of desert dust: implications for human health

    Science.gov (United States)

    Griffin, Dale W.; Ragaini, Richard C.

    2010-01-01

    The global dispersion of desert dust through Earth’s atmosphere is greatly influenced by temperature. Temporal analyses of ice core data have demonstrated that enhanced dust dispersion occurs during glacial events. This is due to an increase in ice cover, which results in an increase in drier terrestrial cover. A shorter temporal analysis of dust dispersion data over the last 40 years has demonstrated an increase in dust transport. Climate systems or events such as the North Atlantic Oscillation, the Indian Ocean subtropical High, Pacific Decadal Oscillation, and El Nino-Sothern Oscillation are known to influence global short-term dust dispersion occurrence and transport routes. Anthropogenic influences on dust transport include deforestation, harmful use of topsoil for agriculture as observed during the American Dust Bowl period, and the creation of dry seas (Aral Sea) and lakes (Lake Owens in California and Lake Chad in North Africa) through the diversion of source waters (for irrigation and drinking water supplies). Constituents of desert dust both from source regions (pathogenic microorganisms, organic and inorganic toxins) and those scavenged through atmospheric transport (i.e., industrial and agricultural emissions) are known to directly impact human and ecosystem health. This presentation will present a review of global scale dust storms and how these events can be both a detriment and benefit to various organisms in downwind environments.

  20. "Hot hand" on strike: bowling data indicates correlation to recent past results, not causality.

    Directory of Open Access Journals (Sweden)

    Gur Yaari

    Full Text Available Recently, the "hot hand" phenomenon regained interest due to the availability and accessibility of large scale data sets from the world of sports. In support of common wisdom and in contrast to the original conclusions of the seminal paper about this phenomenon by Gilovich, Vallone and Tversky in 1985, solid evidences were supplied in favor of the existence of this phenomenon in different kinds of data. This came after almost three decades of ongoing debates whether the "hot hand" phenomenon in sport is real or just a mis-perception of human subjects of completely random patterns present in reality. However, although this phenomenon was shown to exist in different sports data including basketball free throws and bowling strike rates, a somehow deeper question remained unanswered: are these non random patterns results of causal, short term, feedback mechanisms or simply time fluctuations of athletes performance. In this paper, we analyze large amounts of data from the Professional Bowling Association(PBA. We studied the results of the top 100 players in terms of the number of available records (summed into more than 450,000 frames. By using permutation approach and dividing the analysis into different aggregation levels we were able to supply evidence for the existence of the "hot hand" phenomenon in the data, in agreement with previous studies. Moreover, by using this approach, we were able to demonstrate that there are, indeed, significant fluctuations from game to game for the same player but there is no clustering of successes (strikes and failures (non strikes within each game. Thus we were lead to the conclusion that bowling results show correlation to recent past results but they are not influenced by them in a causal manner.

  1. Dust Studies in DIII-D and TEXTOR

    International Nuclear Information System (INIS)

    Rudakov, D.; Litnovsky, A.; West, W.; Yu, J.; Boedo, J.; Bray, B.; Brezinsek, S.; Brooks, N.; Fenstermacher, M.; Groth, M.; Hollmann, E.; Huber, A.; Hyatt, A.; Krasheninnikov, S.; Lasnier, C.; Moyer, R.; Pigarov, A.; Philipps, V.; Pospieszezyk, A.; Smirnov, R.; Sharpe, J.; Solomon, W.; Watkins, J.; Wong, C.

    2008-01-01

    Studies of naturally occurring and artificially introduced carbon dust are conducted in DIII-D and TEXTOR. In DIII-D, dust does not present operational concerns except immediately after entry vents. Energetic plasma disruptions produce significant amounts of dust. However, dust production by disruptions alone is insufficient to account for the estimated in-vessel dust inventory in DIII-D. Submicron sized dust is routinely observed using Mie scattering from a Nd:Yag laser. The source is strongly correlated with the presence of Type I edge localized modes (ELMs). Larger size (0.005-1 mm diameter) dust is observed by optical imaging, showing elevated dust levels after entry vents. Inverse dependence of the dust velocity on the inferred dust size is found from the imaging data. Migration of pre-characterized carbon dust is studied in DIII-D and TEXTOR by injecting micron-size dust in plasma discharges. In DIII-D, a sample holder filled with ∼30 mg of dust is introduced in the lower divertor and exposed to high-power ELMing H-mode discharges with strike points swept across the divertor floor. After a brief exposure (∼0.1 s) at the outer strike point, part of the dust is injected into the plasma, raising the core carbon density by a factor of 2-3 and resulting in a twofold increase of the radiated power. Individual dust particles are observed moving at velocities of 10-100 m/s, predominantly in the toroidal direction, consistent with the drag force from the deuteron flow and in agreement with modeling by the 3D DustT code. In TEXTOR, instrumented dust holders with 1-45 mg of dust are exposed in the scrape-off layer 0-2 cm radially outside of the last closed flux surface in discharges heated with neutral beam injection (NBI) power of 1.4 MW. Dust is launched either in the beginning of a discharge or at the initiation of NBI, preferentially in a direction perpendicular to the toroidal magnetic field. At the given configuration of the launch, the dust did not penetrate

  2. ALSTOM Schusselmuhle fur die feinvermahlung von anhydrit ALSTOM bowl mill for anhydrite fine grinding

    CERN Document Server

    Angleys, M

    2003-01-01

    After the ALSTOM bowl mill had proved a success during numerous laboratory tests using different industrial minerals, for the first time a mill, type SM 20/12 was commissioned for ATLAS s.c. at Lodz /Poland for anhydrite grinding. Based on corresponding laboratory tests with anhydrite, it was possible to adapt the equipment to the requirements of the material with modified properties. Due to the project preparation together with the customer, the mill could be installed and commissioned according to schedule by a joint team of engineers for erection and commissioning.

  3. LADEE LUNAR DUST EXPERIMENT

    Data.gov (United States)

    National Aeronautics and Space Administration — This archive bundle includes data taken by the Lunar Dust Experiment (LDEX) instrument aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft....

  4. Construction dust amelioration techniques.

    Science.gov (United States)

    2012-04-01

    Dust produced on seasonal road construction sites in Alaska is both a traffic safety and environmental concern. Dust emanating from : unpaved road surfaces during construction severely reduces visibility and impacts stopping sight distance, and contr...

  5. On Dust Charging Equation

    OpenAIRE

    Tsintsadze, Nodar L.; Tsintsadze, Levan N.

    2008-01-01

    A general derivation of the charging equation of a dust grain is presented, and indicated where and when it can be used. A problem of linear fluctuations of charges on the surface of the dust grain is discussed.

  6. Physics of interstellar dust

    CERN Document Server

    Krugel, Endrik

    2002-01-01

    The dielectric permeability; How to evaluate grain cross sections; Very small and very big particles; Case studies of Mie calculus; Particle statistics; The radiative transition probability; Structure and composition of dust; Dust radiation; Dust and its environment; Polarization; Grain alignment; PAHs and spectral features of dust; Radiative transport; Diffuse matter in the Milky Way; Stars and their formation; Emission from young stars. Appendices Mathematical formulae; List of symbols.

  7. Dust as a surfactant

    International Nuclear Information System (INIS)

    Ignatov, A M; Schram, P P J M; Trigger, S A

    2003-01-01

    We argue that dust immersed in a plasma sheath acts as a surfactant. By considering the momentum balance in a plasma sheath, we evaluate the dependence of the plasma surface pressure on the dust density. It is shown that the dust may reduce the surface pressure, giving rise to a sufficiently strong tangential force. The latter is capable of confining the dust layer inside the sheath in the direction perpendicular to the ion flow

  8. Migration chemistry

    International Nuclear Information System (INIS)

    Carlsen, L.

    1992-05-01

    Migration chemistry, the influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour of pollutants in the environment, is an interplay between the actual natur of the pollutant and the characteristics of the environment, such as pH, redox conditions and organic matter content. The wide selection of possible pollutants in combination with varying geological media, as well as the operation of different chemical -, biochemical - and physico-chemical reactions compleactes the prediction of the influence of these processes on the mobility of pollutants. The report summarizes a wide range of potential pollutants in the terrestrial environment as well as a variety of chemical -, biochemical - and physico-chemical reactions, which can be expected to influence the migration behaviour, comprising diffusion, dispersion, convection, sorption/desorption, precipitation/dissolution, transformations/degradations, biochemical reactions and complex formation. The latter comprises the complexation of metal ions as well as non-polar organics to naturally occurring organic macromolecules. The influence of the single types of processes on the migration process is elucidated based on theoretical studies. The influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour is unambiguous, as the processes apparently control the transport of pollutants in the terrestrial environment. As the simple, conventional K D concept breaks down, it is suggested that the migration process should be described in terms of the alternative concepts chemical dispersion, average-elution-time and effective retention. (AB) (134 refs.)

  9. Nature of Bonding in Bowl-Like B36 Cluster Revisited: Concentric (6π+18π) Double Aromaticity and Reason for the Preference of a Hexagonal Hole in a Central Location.

    Science.gov (United States)

    Li, Rui; You, Xue-Rui; Wang, Kang; Zhai, Hua-Jin

    2018-05-04

    The bowl-shaped C 6v B 36 cluster with a central hexagon hole is considered an ideal molecular model for low-dimensional boron-based nanosystems. Owing to the electron deficiency of boron, chemical bonding in the B 36 cluster is intriguing, complicated, and has remained elusive despite a couple of papers in the literature. Herein, a bonding analysis is given through canonical molecular orbitals (CMOs) and adaptive natural density partitioning (AdNDP), further aided by natural bond orbital (NBO) analysis and orbital composition calculations. The concerted computational data establish the idea of concentric double π aromaticity for the B 36 cluster, with inner 6π and outer 18π electron counting, which both conform to the (4n+2) Hückel rule. The updated bonding picture differs from existing knowledge of the system. A refined bonding model is also proposed for coronene, of which the B 36 cluster is an inorganic analogue. It is further shown that concentric double π aromaticity in the B 36 cluster is retained and spatially fixed, irrespective of the migration of the hexagonal hole; the latter process changes the system energetically. The hexagonal hole is a destabilizing factor for σ/π CMOs. The central hexagon hole affects substantially fewer CMOs, thus making the bowl-shaped C 6v B 36 cluster the global minimum. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Emerging ecological datasets with application for modeling North American dust emissions

    Science.gov (United States)

    McCord, S.; Stauffer, N. G.; Garman, S.; Webb, N.

    2017-12-01

    In 2011 the US Bureau of Land Management (BLM) established the Assessment, Inventory and Monitoring (AIM) program to monitor the condition of BLM land and to provide data to support evidence-based management of multi-use public lands. The monitoring program shares core data collection methods with the Natural Resources Conservation Service's (NRCS) National Resources Inventory (NRI), implemented on private lands nationally. Combined, the two programs have sampled >30,000 locations since 2003 to provide vegetation composition, vegetation canopy height, the size distribution of inter-canopy gaps, soil texture and crusting information on rangelands and pasture lands across North America. The BLM implements AIM on more than 247.3 million acres of land across the western US, encompassing major dust source regions of the Chihuahuan, Sonoran, Mojave and Great Basin deserts, the Colorado Plateau, and potential high-latitude dust sources in Alaska. The AIM data are publicly available and can be used to support modeling of land surface and boundary-layer processes, including dust emission. While understanding US dust source regions and emission processes has been of national interest since the 1930s Dust Bowl, most attention has been directed to the croplands of the Great Plains and emission hot spots like Owens Lake, California. The magnitude, spatial extent and temporal dynamics of dust emissions from western dust source areas remain highly uncertain. Here, we use ensemble modeling with empirical and physically-based dust emission schemes applied to AIM monitoring data to assess regional-scale patterns of aeolian sediment mass fluxes and dust emissions. The analysis enables connections to be made between dust emission rates at source and other indicators of ecosystem function at the landscape scale. Emerging ecological datasets like AIM provide new opportunities to evaluate aeolian sediment transport responses to land surface conditions, potential interactions with

  11. A vortex-bowl disk atomizer system for the production of alginate beads in a 1500-liter fermentor.

    Science.gov (United States)

    Champagne, C P; Blahuta, N; Brion, F; Gagnon, C

    2000-06-20

    Using a model system, a concept for the immobilization of microbial cultures within alginate beads directly in a 1500-L fermentor with a height to diameter ratio of 1.85 is described. The system is comprised of a 60-cm diameter bowl fixed to the top of an agitation shaft, where calcium-ion-rich media is continuously recirculated from the bulk solution to the bowl. The rotation of the shaft and bowl creates a climbing film (vortex) of solution. An atomizing disk centrally recessed within the bowl sprays an alginate solution into the climbing film where the droplets harden into beads. The effect of heat treatment on the alginate solution on resulting bead properties was examined. The sterilization operation did not appear to have a major effect on the alginate bead mechanical properties of firmness and elasticity which was much more a function of alginate concentration. Beads of various sizes were produced by the unit. The system was characterized by the dimensionless numbers Reomega = (omega x rho x D(2))/mu and ReQ = (Q x rho)/(mu x D). At Reomega and ReQ values less than 500 and 0.15, respectively, the mechanism was direct drop. Parent droplets followed by satellite droplets were observed. When either the flow rate or speed was increased, filaments formed predominantly, which was unwanted in this system because filament breakdown into smaller droplets does not occur due to the proximity of the disk to the climbing film in the bowl. This system could be applied to the immobilization of microorganisms, as well as plant or animal cell cultures, and for other sizes or fermentors. The overflow from the bowl carries the gellified beads into the bulk solution where immobilized cells could act upon the fermentation media. Copyright 2000 John Wiley & Sons, Inc.

  12. Alcohol and violence in 2017 National Football League Super Bowl commercials.

    Science.gov (United States)

    MacLean, Sarah A; Basch, Corey H; Garcia, Philip

    2017-01-01

    Background: The National Football League (NFL) Super Bowl is a widely-viewed sports event and the commercials are especially popular among viewers. Previous research has demonstrated risky health behaviors in advertisements aired during sporting events. The purpose of this study was to analyze the content of the advertisements aired during the 2017 NFL Super Bowl. Methods: This cross-sectional study involved examining the content of all commercials, with an emphasis on health-compromising behaviors. The themes and highlights of the advertisements were analyzed based on whether there was a reference to alcohol or violence. Results: A total of 103 unique commercials were analyzed. The most common themes were humor (n=43), happiness (n=25), innovation (n=25), and enjoyment or relaxation (n=25).Alcohol was referenced in 13 (12.6%, 95% CI 7.5%, 20.4%) of the commercials. Advertisements with alcohol references were more likely to contain the themes of partying (odds ratio [OR]:16.2, 95% CI 1.4-193.4, P=0.041) and enjoyment or relaxation (OR: 4.7, 95% CI 1.4-15.6,P=0.014). There were 24 commercials with references to violence and these were more likely tobe promoting a movie (OR: 5.4, 95% CI 3.5-8.2, Ptelevision program (OR: 8.9,95% CI 2.6-30.26, Pchildren to watch a concentrated number of intense images containing references to alcohol and violence during this popular sporting event.

  13. [The influence of Nintendo-Wii® bowling upon residents of retirement homes].

    Science.gov (United States)

    Wittelsberger, R; Krug, S; Tittlbach, S; Bös, K

    2013-07-01

    The few studies dealing with the positive effects of health and well-being of older people are only one-sided. The aim of the study therefore was to analyze the effects of Nintendo-Wii® bowling on daily function, state of dementia, quality of life, cognition and motor skills in retirement home inhabitants. The study was performed with 27 study participants (13 women, 14 men) between the ages of 49 and 95 years (mean = 71, SD = 14). They were randomly assigned to a control group (KG) and an intervention group (IG). Between pre- and posttest, the IG played 60 min/twice a week Nintendo-Wii® Bowling over 6 weeks. The improvement of IG was significant in the analysis of variance concerning strength (arm curls: F df = 2 = 7.199; p = 0,013; η(2) = 0,231) and showed a significant trend concerning coordination (tracking lines: F df = 2 = 3.99; p = 0,058; η(2) = 0,154) compared with KG. The area of rapidity (catching bars: F df = 2 = 28.511; p = 0,008; η(2) = 0,279) showed a significant decline in the IG compared with the KG. However, closer examination shows that the short time of intervention and the wide age range could have affected the results. Thus, further studies should take these critical aspects into consideration.

  14. Highly open bowl-like PtAuAg nanocages as robust electrocatalysts towards ethylene glycol oxidation

    Science.gov (United States)

    Xu, Hui; Yan, Bo; Li, Shumin; Wang, Jin; Song, Pingping; Wang, Caiqin; Guo, Jun; Du, Yukou

    2018-04-01

    A novel combined seed mediated and galvanic replacement method has been demonstrated to synthesize a new class of trimetallic PtAuAg nanocatalysts with highly open bowl-like nanocage structure. The newly-generated PtAuAg nanocages catalysts exhibit superior electrocatalytic performances towards ethylene glycol oxidation with the mass activity of 6357.1 mA mg-1, 5.5 times higher than that of commercial Pt/C (1151.1 mA mg-1). This work demonstrates the first example of designing shape-controlled architectures of trimetallic bowl-like PtAuAg nanocages for liquid fuel electrooxidation.

  15. Anticancer activities of self-assembled molecular bowls containing a phenanthrene-based donor and Ru(II acceptors

    Directory of Open Access Journals (Sweden)

    Kim I

    2015-08-01

    Full Text Available Inhye Kim,1,* Young Ho Song,2,* Nem Singh,2 Yong Joon Jeong,3 Jung Eun Kwon,3 Hyunuk Kim,4 Young Mi Cho,3 Se Chan Kang,3 Ki-Whan Chi2 1Laboratory of Bio-Resources, Yongin-si, Gyeonggi-Do, 2Department of Chemistry, University of Ulsan, Ulsan, 3Department of Life Science, Gachon University, Seongnam, 4Energy Materials Lab, Korea Institute of Energy Research, Daejeon, Republic of Korea *These authors contributed equally to this work Abstract: Nano-sized multinuclear ruthenium complexes have rapidly emerged as promising therapeutic candidates with unique anticancer activities. Here, we describe the coordination-driven self-assembly and anticancer activities of a set of three organometallic tetranuclear Ru(II molecular bowls. [2+2] Coordination-driven self-assembly of 3,6-bis(pyridin-3-ylethynylphenanthrene (bpep (1 and one of the three dinuclear arene ruthenium clips, [(ƞ6-p-iPrC6H4Me2Ru2-(OO\\OO][OTf]2 (OO\\OO =2,5-dioxido-1,4-benzoquinonato, OTf = triflate (2, 5,8-dioxido-1,4-naphthoquinonato (3, or 6,11-dioxido-5,12-naphthacenediona (4, resulted in three molecular bowls 5–7 of general formula [{(ƞ6-p-iPrC6H4Me2Ru2-(OO\\OO}2(bpep2][OTf]4. All molecular bowls were obtained as triflate salts in very good yields (>90% and were fully characterized using multinuclear nuclear magnetic resonance (NMR, electrospray ionization–mass spectrometry (ESI-MS, and elemental analysis. The structure of the representative molecular bowl 5 was confirmed by single-crystal X-ray diffraction analysis. The anticancer activities of molecular bowls 5–7 were determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide, autophagy, and Western blot analysis. Bowl 6 showed the strongest cytotoxicity in AGS human gastric carcinoma cells and was more cytotoxic than doxorubicin. In addition, autophagic activity and the ratio of apoptotic cell death increased in AGS cells by treatment with bowl 6. Bowl 6 also induced autophagosome formation via upregulation

  16. DUST AND GAS IN THE DISK OF HL TAURI: SURFACE DENSITY, DUST SETTLING, AND DUST-TO-GAS RATIO

    Energy Technology Data Exchange (ETDEWEB)

    Pinte, C.; Ménard, F. [UMI-FCA, CNRS/INSU, France (UMI 3386), and Dept. de Astronomía, Universidad de Chile, Santiago (Chile); Dent, W. R. F.; Hales, A.; Hill, T.; Cortes, P.; Gregorio-Monsalvo, I. de, E-mail: christophe.pinte@obs.ujf-grenoble.fr [Atacama Large Millimeter/Submillimeter Array, Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763-0355, Santiago (Chile)

    2016-01-01

    The recent ALMA observations of the disk surrounding HL Tau reveal a very complex dust spatial distribution. We present a radiative transfer model accounting for the observed gaps and bright rings as well as radial changes of the emissivity index. We find that the dust density is depleted by at least a factor of 10 in the main gaps compared to the surrounding rings. Ring masses range from 10–100 M{sub ⊕} in dust, and we find that each of the deepest gaps is consistent with the removal of up to 40 M{sub ⊕} of dust. If this material has accumulated into rocky bodies, these would be close to the point of runaway gas accretion. Our model indicates that the outermost ring is depleted in millimeter grains compared to the central rings. This suggests faster grain growth in the central regions and/or radial migration of the larger grains. The morphology of the gaps observed by ALMA—well separated and showing a high degree of contrast with the bright rings over all azimuths—indicates that the millimeter dust disk is geometrically thin (scale height ≈1 AU at 100 AU) and that a large amount of settling of large grains has already occurred. Assuming a standard dust settling model, we find that the observations are consistent with a turbulent viscosity coefficient of a few 10{sup −4}. We estimate the gas/dust ratio in this thin layer to be of the order of 5 if the initial ratio is 100. The HCO{sup +} and CO emission is consistent with gas in Keplerian motion around a 1.7 M{sub ⊙} star at radii from ≤10–120 AU.

  17. The Lunar Dust Environment

    Science.gov (United States)

    Szalay, Jamey Robert

    Planetary bodies throughout the solar system are continually bombarded by dust particles, largely originating from cometary activities and asteroidal collisions. Surfaces of bodies with thick atmospheres, such as Venus, Earth, Mars and Titan are mostly protected from incoming dust impacts as these particles ablate in their atmospheres as 'shooting stars'. However, the majority of bodies in the solar system have no appreciable atmosphere and their surfaces are directly exposed to the flux of high speed dust grains. Impacts onto solid surfaces in space generate charged and neutral gas clouds, as well as solid secondary ejecta dust particles. Gravitationally bound ejecta clouds forming dust exospheres were recognized by in situ dust instruments around the icy moons of Jupiter and Saturn, and had not yet been observed near bodies with refractory regolith surfaces before NASA's Lunar Dust and Environment Explorer (LADEE) mission. In this thesis, we first present the measurements taken by the Lunar Dust Explorer (LDEX), aboard LADEE, which discovered a permanently present, asymmetric dust cloud surrounding the Moon. The global characteristics of the lunar dust cloud are discussed as a function of a variety of variables such as altitude, solar longitude, local time, and lunar phase. These results are compared with models for lunar dust cloud generation. Second, we present an analysis of the groupings of impacts measured by LDEX, which represent detections of dense ejecta plumes above the lunar surface. These measurements are put in the context of understanding the response of the lunar surface to meteoroid bombardment and how to use other airless bodies in the solar system as detectors for their local meteoroid environment. Third, we present the first in-situ dust measurements taken over the lunar sunrise terminator. Having found no excess of small grains in this region, we discuss its implications for the putative population of electrostatically lofted dust.

  18. The effect of spin in swing bowling in cricket: model trajectories for spin alone

    Science.gov (United States)

    Robinson, Garry; Robinson, Ian

    2015-02-01

    In ‘swing’ bowling, as employed by fast and fast-medium bowlers in cricket, back-spin along the line of the seam is normally applied in order to keep the seam vertical and to provide stability against ‘wobble’ of the seam. Whilst spin is normally thought of as primarily being the slow bowler's domain, the spin applied by the swing bowler has the side-effect of generating a lift or Magnus force. This force, depending on the orientation of the seam and hence that of the back-spin, can have a side-ways component as well as the expected vertical ‘lift’ component. The effect of the spin itself, in influencing the trajectory of the fast bowler's delivery, is normally not considered, presumably being thought of as negligible. The purpose of this paper is to investigate, using calculated model trajectories, the amount of side-ways movement due to the spin and to see how this predicted movement compares with the total observed side-ways movement. The size of the vertical lift component is also estimated. It is found that, although the spin is an essential part of the successful swing bowler's delivery, the amount of side-ways movement due to the spin itself amounts to a few centimetres or so, and is therefore small, but perhaps not negligible, compared to the total amount of side-ways movement observed. The spin does, however, provide a considerable amount of lift compared to the equivalent delivery bowled without spin, altering the point of pitching by up to 3 m, a very large amount indeed. Thus, for example, bowling a ball with the seam pointing directly down the pitch and not designed to swing side-ways at all, but with the amount of back-spin varied, could provide a very powerful additional weapon in the fast bowler's arsenal. So-called ‘sling bowlers’, who use a very low arm action, can take advantage of spin since effectively they can apply side-spin to the ball, giving rise to a large side-ways movement, ˜ 20{}^\\circ cm or more, which certainly is

  19. Migrating Worker

    DEFF Research Database (Denmark)

    Hansen, Hans

    This is the preliminary report on the results obtained in the Migrating Worker-project. This project was initiated by the Danish Ministry of Finance with the aim of illustrating the effects of the 1408/71 agreement and the bilateral double taxation agreements Denmark has with the countries included...

  20. Dateline Migration.

    Science.gov (United States)

    Tomasi, Lydio E., Ed.

    1995-01-01

    Presents data on international migration and its effects in and between various countries in North America, Europe, and Africa. Discussions include refugee, immigrant, and migrant worker flows; the legal, political, and social problems surrounding immigrants; alien terrorism and law enforcement problems; and migrant effects on education, social…

  1. Bowling apart?’ : Vier vragen over Nederlandse sportclubs en omgang tussen arm en rijk

    NARCIS (Netherlands)

    Meulen, Ruud van der; Ruiter, Stijn; Ultee, Wout

    2005-01-01

    Bowling apart?’ Four questions on poor-rich contact in Dutch sports clubs This article tests Bourdieu’s and Putnam’s competing views on sports clubs as class mixers, using crosssectional Dutch survey data for the early 1980s and late 1990s. We calculate popularity and representativity indices.

  2. Online Responses to a Multilingual Super Bowl Ad: Is "America the Beautiful" by Any Other Language Still America, the Beautiful?

    Science.gov (United States)

    Hoffman, Brooke Y.

    2016-01-01

    On 2 February 2014, an advertisement entitled "It's Beautiful" debuted during Super Bowl XLVIII, which was watched by 111.5 million people in the USA. The Coca-Cola advertisement portrayed people of various ethnicities and was accompanied by "America the Beautiful" sung in nine languages. Using critical discourse analysis, I…

  3. Survival of Salmonella Copenhagen in food bowls following contamination with experimentally inoculated raw meat: Effects of time, cleaning, and disinfection

    OpenAIRE

    Weese, J Scott; Rousseau, J.

    2006-01-01

    There are concerns regarding the safety of feeding raw meat to household pets. This study demonstrated that Salmonella persists in food bowls that are inoculated with Salmonella-containing raw meat. Standard methods of cleaning and disinfection were minimally effective at eliminating Salmonella contamination.

  4. Simulation of W dust transport in the KSTAR tokamak, comparison with fast camera data

    Directory of Open Access Journals (Sweden)

    A. Autricque

    2017-08-01

    Full Text Available In this paper, dust transport in tokamak plasmas is studied through both experimental and modeling aspects. Image processing routines allowing dust tracking on CCD camera videos are presented. The DUMPRO (DUst Movie PROcessing code features a dust detection method and a trajectory reconstruction algorithm. In addition, a dust transport code named DUMBO (DUst Migration in a plasma BOundary is briefly described. It has been developed at CEA in order to simulate dust grains transport in tokamaks and to evaluate the contribution of dust to the impurity inventory of the plasma. Like other dust transport codes, DUMBO integrates the Orbital Motion Limited (OML approach for dust/plasma interactions modeling. OML gives direct expressions for plasma ions and electrons currents, forces and heat fluxes on a dust grain. The equation of motion is solved, giving access to the dust trajectory. An attempt of model validation is made through comparison of simulated and measured trajectories on the 2015 KSTAR dust injection experiment, where W dust grains were successfully injected in the plasma using a gun-type injector. The trajectories of the injected particles, estimated using the DUMPRO routines applied on videos from the fast CCD camera in KSTAR, show two distinct general dust behaviors, due to different dust sizes. Simulations were made with DUMBO to match the measurements. Plasma parameters were estimated using different diagnostics during the dust injection experiment plasma discharge. The experimental trajectories show longer lifetimes than the simulated ones. This can be due to the substitution of a boiling/sublimation point to the usual vaporization/sublimation cooling, OML limitations (eventual potential barriers in the vicinity of a dust grain are neglected and/or to the lack of a vapor shielding model in DUMBO.

  5. On Tea Bowl from Jianzhan to Tenmoku: Material Culture and Intangible Culture in Cultural Diffusion

    Directory of Open Access Journals (Sweden)

    Jianping Guan

    2014-12-01

    Full Text Available According to precise and scientific literature that recorded, Chinese tea culture has a documented history of more than 1700 years. During which period, Yuan Dynasty was considered a crucial turning-point with great changes. The current tea culture in China is an adoption and innovation of Ming and Qing dynasty, especially in the form of processing technology. For those elements inherited from Tang and Song dynasties, however, they were more directly adopted systematically by Japan. Ever since powdered tea culture from Song dynasty was accepted in Japan, Jianzhan, the tea bowl that gained renowned reputation in the Song tea culture was also introduced and became tenmoku (tianmu after localization. As the transformation of Chinese tea culture ended in Japan, Japanese tea culture of wabi-cha was shaped after the tenmoku’s obvious decline in value. Jianzhan’s prosper, and tenmoku’s emergence and transition, all proved a definitive impact from intangible culture.

  6. THE EFFECT OF BOWLING GAME TOWARD NUMERACY SKILLS FOR INTELLECTUAL DISABILITY STUDENT

    Directory of Open Access Journals (Sweden)

    Putri Dwi Sari

    2016-12-01

    Full Text Available Intellectual disability students experience difficulties in the learning process, especially on the material arithmeti coperation. It was caused by to the intellectual development hampered by the limitations of IQ and final stage of operational phases of the students turn from abstract to the concrete. The research design used in this study was the Single Subject Research (SSR, with ABA design models and use measuring units scores. The subjects was intellectual disability students the fifth grade in SDLB Idayu II Malang. Data collection techniques was written tests. Research revealed a effect of the use of the bowling game to increaser eduction numeracy skills as the target behavior. Advice for school and the teacher can provide methods and learning media in accordance with the needs and characteristics of students..

  7. The Byzantine Silver Bowls in the Sutton Hoo Ship Burial and Tree-Worship in Anglo-Saxon England

    Directory of Open Access Journals (Sweden)

    Michael D. J. Bintley

    2011-12-01

    Full Text Available The ten Byzantine silver bowls included amongst the grave goods interred in the chamber of the Mound 1 ship burial at Sutton Hoo remain one of the most puzzling features of this site. It has been suggested that these items, which lay separated from the rest of the silver in the burial and close to the head of the body-space (where no body was found, may have had some special meaning which has never been discovered. This paper will argue that one of the possible keys to unlocking their significance may be found in the central roundel that adorns the centre of each bowl in the form of a rosette. These bowls, which are thought to have been manufactured in the eastern provinces of the Byzantine Empire in c. 600, entered the British Isles in unknown circumstances before coming into the possession of the man buried in (or commemorated by the Mound 1 burial. Through comparison with contemporary sculpture and vernacular literature, I will suggest that this central rosette, which was associated with both the cross of Christ and sacred trees in Byzantine sculpture, may have served as a conventional bridge between Christian and pre-Christian religious traditions associated with sacred trees in Anglo-Saxon England. The central rosettes adorning each of these bowls may have been understood as the flower of a sacred tree. Since the latter appears to have figured in Anglian paganism it is possible that the bowls may helped to convert the Anglian aristocracy, bridging a gap between Germanic insular religious traditions and those that were being introduced to Britain at the time that the ship burial itself took place.

  8. Dust Devil Tracks

    Science.gov (United States)

    2002-01-01

    (Released 8 May 2002) The Science This image, centered near 50.0 S and 17.7 W displays dust devil tracks on the surface. Most of the lighter portions of the image likely have a thin veneer of dust settled on the surface. As a dust devil passes over the surface, it acts as a vacuum and picks up the dust, leaving the darker substrate exposed. In this image there is a general trend of many of the tracks running from east to west or west to east, indicating the general wind direction. There is often no general trend present in dust devil tracks seen in other images. The track patterns are quite ephemeral and can completely change or even disappear over the course of a few months. Dust devils are one of the mechanisms that Mars uses to constantly pump dust into the ubiquitously dusty atmosphere. This atmospheric dust is one of the main driving forces of the present Martian climate. The Story Vrrrrooooooooom. Think of a tornado, the cartoon Tasmanian devil, or any number of vacuum commercials that powerfully suck up swirls of dust and dirt. That's pretty much what it's like on the surface of Mars a lot of the time. Whirlpools of wind called

  9. Alcohol and violence in 2017 National Football League Super Bowl commercials

    Directory of Open Access Journals (Sweden)

    Sarah A. MacLean

    2017-06-01

    Full Text Available Background: The National Football League (NFL Super Bowl is a widely-viewed sports event and the commercials are especially popular among viewers. Previous research has demonstrated risky health behaviors in advertisements aired during sporting events. The purpose of this study was to analyze the content of the advertisements aired during the 2017 NFL Super Bowl. Methods: This cross-sectional study involved examining the content of all commercials, with an emphasis on health-compromising behaviors. The themes and highlights of the advertisements were analyzed based on whether there was a reference to alcohol or violence. Results: A total of 103 unique commercials were analyzed. The most common themes were humor (n=43, happiness (n=25, innovation (n=25, and enjoyment or relaxation (n=25.Alcohol was referenced in 13 (12.6%, 95% CI 7.5%, 20.4% of the commercials. Advertisements with alcohol references were more likely to contain the themes of partying (odds ratio [OR]:16.2, 95% CI 1.4-193.4, P=0.041 and enjoyment or relaxation (OR: 4.7, 95% CI 1.4-15.6,P=0.014. There were 24 commercials with references to violence and these were more likely tobe promoting a movie (OR: 5.4, 95% CI 3.5-8.2, P<0.001 or television program (OR: 8.9,95% CI 2.6-30.26, P<0.001. Conclusion: Parents should consider whether it is appropriate for their children to watch a concentrated number of intense images containing references to alcohol and violence during this popular sporting event.

  10. Whither Cometary Dust?

    Science.gov (United States)

    Lisse, Carey M.

    2010-10-01

    In this paper I will discuss recent findings that have important implications for our understanding of the formation and evolution of primitive solar system dust, including: - Nesvorny et al. (2010), following up on their dynamical analyses of the zodiacal dust bands as sourced by the breakup of the Karin (5Mya) and Veritas (8Mya) asteroid families, argue that over 90% of the interplanetary dust cloud at 1 AU comes from JFC comets with near-circularized, low inclination orbits. This implies that the noted IPD collections of anhydrous and hydrous dust particles are likely to be from Oort cloud and JFC comets, respectively, not from asteroids and comets as thought in the past. Hydrous dust particles from comets like 85P/Wild2 and 9P/Tempel 1 would be consistent with results from the STARDUST and Deep Impact experiments. - Estimates of the dust particle size distributions (PSDs) in the comae of 85P/Wild2 (Green et al. 2004, 2007) and 73P/SW-3 (Sitko et al. 2010, Vaubaillon & Reach 2010) and in the trails of comets (Reach et al. 2007) have broken power law structure, with a plateau enhancement of particles of 1 mm - 1 cm in size. This size is also the size of most chondritic inclusions, and the predicted size range of the "aggregational barrier", where collisions between dust particles become destructive. - Studies of the albedo and polarization properties of cometary dust (Kolokolova et al. 2007) suggest there are 2 major groupings, one with low scattering capability and one with high. While these families could possibly have been explained by systematics in the PSDs of the emitted dust, independent work by Lisse et al. (2008) on the mineralogy of a number of highly dusty comets has shown evidence for one family of comets with highly crystalline dust and another with highly amorphous dust.

  11. Communication plan for windblown dust.

    Science.gov (United States)

    2015-05-01

    Windblown dust events occur in Arizona, and blowing dust has been considered a contributing factor to serious crashes on the : segment of Interstate 10 (I10) between Phoenix and Tucson, as well as on other Arizona roadways. Arizonas dust events...

  12. Studies on the influence of combustion bowl modification for the operation of Cymbopogon flexuosus biofuel based diesel blends in a DI diesel engine

    International Nuclear Information System (INIS)

    Dhinesh, B.; Annamalai, M.; Lalvani, Isaac JoshuaRamesh; Annamalai, K.

    2017-01-01

    Highlights: • A novel biofuel, Cymbopogon flexuosus is used as an alternative energy source. • C20-D80 + 20 ppm profile stayed close to diesel fuel with BB. • Three different combustion bowl CB1, CB2, and CB3 were considered. • Resulting in higher thermal efficiency and lower HC, CO, emission. • Reduction of oxides of nitrogen and smoke emission for C20-D80 + 20 ppm and CB2. - Abstract: The aim of this experimental work is to figure out the optimized the combustion bowl geometry on a constant speed diesel engine for its efficient functioning with a novel biofuel. The novel biofuel considered for this research work was Cymbopogon flexuosus biofuel. To improve the performance level, 20% Cymbopogon flexuosus biofuel was blended with 80% of diesel fuel (C20-D80) and to further reduce the emission magnitude, 20 ppm of cerium oxide was added to the blended fuel (C20-D80 + 20 ppm). For this study four different combustion bowls were designed based on the keen literature survey. They were hemispherical combustion bowl (BB), shallow depth re-entrant combustion bowl (CB1), Toroidal re-entrant combustion bowl (CB2), Toroidal combustion bowl (CB3). Based on the experimental evaluation, the results have been discussed for low load and full load conditions for better understanding. Regarding the fuel modification, C20-D80 + 20 ppm resulted in better engine characteristics owing to combined effect of the oxygen molecule bearing fuel and superior thermal stability and activation energy of the cerium oxide nanoparticle. Of the various bowls considered for the tests, the combustion bowl CB2 showed superior performance and emission reduction compared with its competitors CB1, CB2, and BB. It could have ascribed to the better mixing rate, gain of swirl velocity and the turbulence level of the bowl. CB2 resulted in higher BTE and lower BSEC of 4.1% and 12.02% in low and full load conditions for C20-D80 + 20 ppm. Emission reduction observed was 17% of HC, 43.66% of CO and

  13. A preference for migration

    OpenAIRE

    Stark, Oded

    2007-01-01

    At least to some extent migration behavior is the outcome of a preference for migration. The pattern of migration as an outcome of a preference for migration depends on two key factors: imitation technology and migration feasibility. We show that these factors jointly determine the outcome of a preference for migration and we provide examples that illustrate how the prevalence and transmission of a migration-forming preference yield distinct migration patterns. In particular, the imitation of...

  14. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Mathis, J.S.

    1978-01-01

    The author's review concentrates on theoretical aspects of dust in planetary nebulae (PN). He considers the questions: how much dust is there is PN; what is its composition; what effects does it have on the ionization structure, on the dynamics of the nebula. (Auth.)

  15. Toxicity of lunar dust

    NARCIS (Netherlands)

    Linnarsson, D.; Carpenter, J.; Fubini, B.; Gerde, P.; Loftus, D.; Prisk, K.; Staufer, U.; Tranfield, E.; van Westrenen, W.

    2012-01-01

    The formation, composition and physical properties of lunar dust are incompletely characterised with regard to human health. While the physical and chemical determinants of dust toxicity for materials such as asbestos, quartz, volcanic ashes and urban particulate matter have been the focus of

  16. Combustible dust tests

    Science.gov (United States)

    The sugar dust explosion in Georgia on February 7, 2008 killed 14 workers and injured many others (OSHA, 2009). As a consequence of this explosion, OSHA revised its Combustible Dust National Emphasis (NEP) program. The NEP targets 64 industries with more than 1,000 inspections and has found more tha...

  17. Respirable dust measured downwind during rock dust application.

    Science.gov (United States)

    Harris, M L; Organiscak, J; Klima, S; Perera, I E

    2017-05-01

    The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted underground evaluations in an attempt to quantify respirable rock dust generation when using untreated rock dust and rock dust treated with an anticaking additive. Using personal dust monitors, these evaluations measured respirable rock dust levels arising from a flinger-type application of rock dust on rib and roof surfaces. Rock dust with a majority of the respirable component removed was also applied in NIOSH's Bruceton Experimental Mine using a bantam duster. The respirable dust measurements obtained downwind from both of these tests are presented and discussed. This testing did not measure miners' exposure to respirable coal mine dust under acceptable mining practices, but indicates the need for effective continuous administrative controls to be exercised when rock dusting to minimize the measured amount of rock dust in the sampling device.

  18. Lunar Dust Mitigation Screens

    Science.gov (United States)

    Knutson, Shawn; Holloway, Nancy

    With plans for the United States to return to the moon, and establish a sustainable human presence on the lunar surface many issues must be successfully overcome. Lunar dust is one of a number of issues with the potential to create a myriad of problems if not adequately addressed. Samples of dust brought back from Apollo missions show it to be soft, yet sharp and abrasive. The dust consists of a variety of morphologies including spherical, angular blocks, shards, and a number of irregular shapes. One of the main issues with lunar dust is its attraction to stick to anything it comes in contact with (i.e. astronauts, equipment, habitats, etc.). Ionized radiation from the sun strikes the moon's surface and creates an electrostatic charge on the dust. Further, the dust harbors van der Waals forces making it especially difficult to separate once it sticks to a surface. During the Apollo missions, it was discovered that trying to brush the lunar dust from spacesuits was not effective, and rubbing it caused degradation of the suit material. Further, when entering the lunar module after moonwalks, the astronauts noted that the dust was so prolific inside the cabin that they inhaled and ingested it, causing at least one of them, Harrison "Jack" Schmidt, to report irritation of the throat and lungs. It is speculated that the dust could also harm an astronaut's nervous and cardiovascular systems, especially during an extended stay. In addition to health issues, the dust can also cause problems by scouring reflective coatings off of thermal blankets, and roughening surfaces of windows and optics. Further, panels on solar cells and photovoltaics can also be compromised due to dust sticking on the surfaces. Lunar dust has the capacity to penetrate seals, interfere with connectors, as well as mechanisms on digging machines, all of which can lead to problems and failure. To address lunar dust issues, development of electrostatic screens to mitigate dust on sur-faces is currently

  19. Quantifying Anthropogenic Dust Emissions

    Science.gov (United States)

    Webb, Nicholas P.; Pierre, Caroline

    2018-02-01

    Anthropogenic land use and land cover change, including local environmental disturbances, moderate rates of wind-driven soil erosion and dust emission. These human-dust cycle interactions impact ecosystems and agricultural production, air quality, human health, biogeochemical cycles, and climate. While the impacts of land use activities and land management on aeolian processes can be profound, the interactions are often complex and assessments of anthropogenic dust loads at all scales remain highly uncertain. Here, we critically review the drivers of anthropogenic dust emission and current evaluation approaches. We then identify and describe opportunities to: (1) develop new conceptual frameworks and interdisciplinary approaches that draw on ecological state-and-transition models to improve the accuracy and relevance of assessments of anthropogenic dust emissions; (2) improve model fidelity and capacity for change detection to quantify anthropogenic impacts on aeolian processes; and (3) enhance field research and monitoring networks to support dust model applications to evaluate the impacts of disturbance processes on local to global-scale wind erosion and dust emissions.

  20. Staffing Levels at National Collegiate Athletic Association Football Bowl Subdivision-Level Institutions.

    Science.gov (United States)

    Ms, Suzie Aparicio; Welch Bacon, Cailee E; Parsons, John T; Bay, R Curtis; Cohen, Randy P; DeZeeuw, Terry; McLeod, Tamara C Valovich

    2015-12-01

    The "Appropriate Medical Coverage for Intercollegiate Athletics" (AMCIA) document was created to support assessment and calculation of athletic training personnel requirements. However, little is known regarding disparities between current and recommended staffing practices. To identify the staffing and employment characteristics of athletic health care services at Football Bowl Subdivision-level institutions. Cross-sectional study. Web-based survey. Head athletic trainers and athletic training staff members who were knowledgeable about budget and staff. The survey, Assessment of Staffing Levels at National Collegiate Athletic Association Football Bowl Subdivision-Level Institutions, was used to evaluate personal, university, and staff demographics; staffing and employment topics; and AMCIA variables and use. The survey was accessed and partially completed by 104 individuals (response rate = 84.6%). A total of 79 athletic trainers (response rate = 76%) completed the entire survey. One-third of the respondents (34.2%, n = 26) met the recommended number of full-time equivalents (FTEs) for football, two-thirds of the respondents (65.7%, n = 50) failed to meet the recommendation, and 26.2% (n = 27) were missing data needed for FTE calculation. Among those who did not meet the recommended FTEs (n = 50), 38.0% (n = 19) were within 1 FTE of being compliant, 26.0% (n = 13) were within 2 FTEs, and 24.0% (n = 12) were within 3 FTEs. About one-third of respondents (35.9%, n = 37) reported not using the AMCIA, citing lack of funding (29.7%, n = 11), lack of administrative support (21.6%, n = 8), and other reasons (37.8%, n = 14). The majority of institutions that used the AMCIA were able to provide justification for staffing. For most of the institutions that failed to meet their recommendation, adding 1-3 FTE athletic trainers for football would change their compliance status. A uniform definition of the term FTE within collegiate athletics is needed to allow for structured

  1. King's Bowl Pit Crater, Lava Field and Eruptive Fissure, Idaho - A Multipurpose Volcanic Planetary Analog

    Science.gov (United States)

    Hughes, S. S.; Garry, B.; Kobs-Nawotniak, S. E.; Sears, D. W. G.; Borg, C.; Elphic, R. C.; Haberle, C. W.; Kobayashi, L.; Lim, D. S. S.; Sears, H.; Skok, J. R.; Heldmann, J. L.

    2014-12-01

    King's Bowl (KB) and its associated eruptive fissure and lava field on the eastern Snake River Plain, is being investigated by the NASA SSERVI FINESSE (Field Investigations to Enable Solar System Science and Exploration) team as a planetary analog to similar pits on the Moon, Mars and Vesta. The 2,220 ± 100 BP basaltic eruption in Craters of the Moon National Monument and Preserve represents early stages of low shield growth, which was aborted when magma supply was cut off. Compared to mature shields, KB is miniscule, with ~0.02 km3 of lava over ~3 km2, yet the ~6 km long series of fissures, cracks and pits are well-preserved for analog studies of volcanic processes. The termination of eruption was likely related to proximity of the 2,270 ± 50 BP eruption of the much larger Wapi lava field (~5.5 km3 over 325 km2 area) on the same rift. Our investigation extends early work by R. Greeley and colleagues, focusing on imagery, compositional variations, ejecta distribution, dGPS profiles and LiDAR scans of features related to: (1) fissure eruptions - spatter ramparts, cones, feeder dikes, extension cracks; (2) lava lake formation - surface morphology, squeeze-ups, slab pahoehoe lava mounds, lava drain-back, flow lobe overlaps; and (3) phreatic steam blasts - explosion pits, ejecta blankets of ash and blocks. Preliminary results indicate multiple fissure eruptions and growth of a basin-filled lava lake up to ~ 10 m thick with outflow sheet lava flows. Remnant mounds of original lake crust reveal an early high lava lake level, which subsided as much as 5 m as the molten interior drained back into the fissure system. Rapid loss of magma supply led to the collapse of fissure walls allowing groundwater influx that triggered multiple steam blasts along at least 500 m. Early blasts occurred while lake magma pressure was still high enough to produce squeeze-ups when penetrated by ejecta blocks. The King's Bowl pit crater exemplifies processes of a small, but highly energetic

  2. Staffing Levels at National Collegiate Athletic Association Football Bowl Subdivision-Level Institutions

    Science.gov (United States)

    MS, Suzie Aparicio; Welch Bacon, Cailee E.; Parsons, John T.; Bay, R. Curtis; Cohen, Randy P.; DeZeeuw, Terry; McLeod, Tamara C. Valovich

    2015-01-01

    Context The “Appropriate Medical Coverage for Intercollegiate Athletics” (AMCIA) document was created to support assessment and calculation of athletic training personnel requirements. However, little is known regarding disparities between current and recommended staffing practices. Objective To identify the staffing and employment characteristics of athletic health care services at Football Bowl Subdivision-level institutions. Design Cross-sectional study. Setting Web-based survey. Patients or Other Participants Head athletic trainers and athletic training staff members who were knowledgeable about budget and staff. Main Outcome Measure(s) The survey, Assessment of Staffing Levels at National Collegiate Athletic Association Football Bowl Subdivision-Level Institutions, was used to evaluate personal, university, and staff demographics; staffing and employment topics; and AMCIA variables and use. Results The survey was accessed and partially completed by 104 individuals (response rate = 84.6%). A total of 79 athletic trainers (response rate = 76%) completed the entire survey. One-third of the respondents (34.2%, n = 26) met the recommended number of full-time equivalents (FTEs) for football, two-thirds of the respondents (65.7%, n = 50) failed to meet the recommendation, and 26.2% (n = 27) were missing data needed for FTE calculation. Among those who did not meet the recommended FTEs (n = 50), 38.0% (n = 19) were within 1 FTE of being compliant, 26.0% (n = 13) were within 2 FTEs, and 24.0% (n = 12) were within 3 FTEs. About one-third of respondents (35.9%, n = 37) reported not using the AMCIA, citing lack of funding (29.7%, n = 11), lack of administrative support (21.6%, n = 8), and other reasons (37.8%, n = 14). Conclusions The majority of institutions that used the AMCIA were able to provide justification for staffing. For most of the institutions that failed to meet their recommendation, adding 1–3 FTE athletic trainers for football would change their

  3. Spirit Feels Dust Gust

    Science.gov (United States)

    2007-01-01

    On sol 1149 (March 28, 2007) of its mission, NASA's Mars Exploration Rover Spirit caught a wind gust with its navigation camera. A series of navigation camera images were strung together to create this movie. The front of the gust is observable because it was strong enough to lift up dust. From assessing the trajectory of this gust, the atmospheric science team concludes that it is possible that it passed over the rover. There was, however, no noticeable increase in power associated with this gust. In the past, dust devils and gusts have wiped the solar panels of dust, making it easier for the solar panels to absorb sunlight.

  4. An experimental investigation on the influence of piston bowl geometry on RCCI performance and emissions in a heavy-duty engine

    OpenAIRE

    Benajes Calvo, Jesus Vicente; Pastor Soriano, José Vicente; García Martínez, Antonio; Monsalve Serrano, Javier

    2015-01-01

    This experimental work investigates the effects of piston bowl geometry on RCCI performance and emissions at low, medium and high engine loads. For this purpose three different piston bowl geometries with compression ratio 14.4:1 have been evaluated using single and double injection strategies. The experiments were conducted in a heavy-duty single-cylinder engine adapted for dual fuel operation. All the tests were carried out at 1200 rev/min. Results suggest that piston geometry has grea...

  5. Biofilm-forming activity of bacteria isolated from toilet bowl biofilms and the bactericidal activity of disinfectants against the isolates.

    Science.gov (United States)

    Mori, Miho; Gomi, Mitsuhiro; Matsumune, Norihiko; Niizeki, Kazuma; Sakagami, Yoshikazu

    2013-01-01

    To evaluate the sanitary conditions of toilets, the bacterial counts of the toilet bowl biofilms in 5 Kansai area and 11 Kansai and Kanto area homes in Japan were measured in winter and summer seasons, respectively. Isolates (128 strains) were identified by analyzing 16S ribosomal RNA sequences. The number of colonies and bacterial species from biofilms sampled in winter tended to be higher and lower, respectively, than those in summer. Moreover, the composition of bacterial communities in summer and winter samples differed considerably. In summer samples, biofilms in Kansai and Kanto areas were dominated by Blastomonas sp. and Mycobacterium sp., respectively. Methylobacterium sp. was detected in all toilet bowl biofilms except for one sample. Methylobacterium sp. constituted the major presence in biofilms along with Brevundimonas sp., Sphingomonas sp., and/or Pseudomonas sp. The composition ratio of the sum of their genera was 88.0 from 42.9% of the total bacterial flora. The biofilm formation abilities of 128 isolates were investigated, and results suggested that Methylobacterium sp. and Sphingomonas sp. were involved in biofilm formation in toilet bowls. The biofilm formation of a mixed bacteria system that included bacteria with the highest biofilm-forming ability in a winter sample was greater than mixture without such bacteria. This result suggests that isolates possessing a high biofilm-forming activity are involved in the biofilm formation in the actual toilet bowl. A bactericidal test against 25 strains indicated that the bactericidal activities of didecyldimethylammonium chloride (DDAC) tended to be higher than those of polyhexamethylene biguanide (PHMB) and N-benzyl-N,N-dimethyldodecylammonium chloride (ADBAC). In particular, DDAC showed high bactericidal activity against approximately 90% of tested strains under the 5 h treatment.

  6. Modeling study on the effect of piston bowl geometries in a gasoline/biodiesel fueled RCCI engine at high speed

    International Nuclear Information System (INIS)

    Li, J.; Yang, W.M.; Zhou, D.Z.

    2016-01-01

    Highlights: • The RCCI engine fueled with gasoline and biodiesel is simulated. • The effect of piston bowl geometry is investigated. • The throat diameter of a piston can affect combustion process. • SCC shows superiority among three investigated geometries for RCCI combustion. - Abstract: This paper reports the numerical investigation on the effects of three bowl geometries on a gasoline/biodiesel fueled RCCI engine operated at high engine speed. The three bowl geometries are HCC (Hemispherical Combustion Chamber), SCC (Shallow depth Combustion Chamber) and OCC (Omega Combustion Chamber). To simulate the combustion in an RCCI engine, coupled KIVA4–CHEMKIN code was used. One recently developed reaction mechanism, which contains 107 species and 425 reactions, was adopted in this study to mimic the combustion of gasoline and biodiesel. During the simulation, the engine speed was fixed at 3600 rpm. The low reactivity fuel gasoline was premixed with air with energy percentages of 20% and 40%; accordingly, to maintain the same energy input, the percentages of biodiesel were 80% and 60% (B80 and B60). In addition, the SOI timing was varied at three levels: −11, −35 and −60 deg ATDC for B80 and B60, respectively. With SOI timing of −11 deg ATDC, the combustion is mixing-controlled; in contrast, advancing SOI timing to −60 deg ATDC, the combustion turns into the reactivity-controlled. Comparing the results on combustion characteristics, engine performance and emissions among different bowl geometries, it is concluded that the original OCC design for Toyota diesel engine is better for mixing-controlled combustion; whereas, SCC is the most suitable piston design for RCCI combustion among the three selected geometries under the investigated operating conditions of the engine. With SCC, better combustion and performance can be achieved while maintaining relatively lower CO, NO and soot emissions.

  7. Characterization of microorganisms isolated from the black dirt of toilet bowls and componential analysis of the black dirt.

    Science.gov (United States)

    Mori, Miho; Nagata, Yusuke; Niizeki, Kazuma; Gomi, Mitsuhiro; Sakagami, Yoshikazu

    2014-01-01

    We have previously conducted a microflora analysis and examined the biofilm-forming activity of bacteria isolated from toilet bowl biofilms. In the present investigation, to reveal the strain involved in the formation of black dirt in toilet bowls, we performed a microflora analysis of the bacteria and fungi isolated from the black dirt of toilet bowls at ten homes. Among samples from different isolation sites and sampling seasons, although a similar tendency was not seen in bacterial microflora, Exophiala sp. was detected in the fungal microflora from all samples of black dirt except for one, and constituted the major presence. By scanning electron microscope (SEM) analysis of the formed black dirt, SEM image at × 1,000 and × 5,000 magnification showed objects like hyphae and many bacteria adhering to them, respectively. Micro fourier transform infrared spectroscopy (micro FT-IR) and SEM with X-ray microanalysis (SEM-XMA) were used to investigate the components of black dirt. IR spectra of micro-FT-IR showed typical absorptions associated with amide compounds and protein, and the elements such as C, N, O, Na, Mg, Al, Si, P, S, K, and Ba were detected with SEM-XMA. These results showed that black dirt had living body ingredients. Furthermore, Exophiala sp. and Cladosporium sp. strains, which were observed at a high frequency, accumulated 2-hydroxyjuglone (2-HJ) and flaviolin as one of the intermediates in the melanin biosynthetic pathway by the addition of a melanin synthesis inhibitor (tricyclazole) at the time of cultivation. These results suggested strongly that the pigment of black dirt in toilet bowls was melanin produced by Exophiala sp. and Cladosporium sp. strains.

  8. Review Essay: A Nation, a World, in a Bowl of Tea

    Directory of Open Access Journals (Sweden)

    Dana Buntrock

    2013-06-01

    Full Text Available Fujimori Terunobu. 藤森照信. Fujimori Terunobu no Chashitsugaku: Nihon no Kyokushō Kūkan no Nazo [Fujimori Terunobu’s tearoom studies: The riddle of Japan’s smallest space]. 藤森照信の茶室学。日本の極小空間の謎. Tokyo: Rikuyosha, 2012. 296 pp. ¥3,000 (cloth.Surak, Kristin. Making Tea, Making Japan: Cultural Nationalism in Practice. Stanford, CA: Stanford University Press, 2012. 272 pp. $85 (cloth, $25 (paper/ebook.The tea in Surak’s bowl is bright green matcha whipped with a whisk; Fujimori’s is steeped sencha heated over a tiny bed of coals. Fujimori’s funky tea seems to be the antithesis of the refined practices Surak strives to embody. Only occasionally does a communicant in Fujimori’s tea space wear a kimono, and there is no reason to worry about treading on the silk borders of a tatami, because his floors are usually finished in other, more modest, materials. Fujimori’s tea is one that can accept outside influences; Surak’s sits complacently at the center of an industry built on centuries of history. Surak shares the conventions of tea; Fujimori celebrates its unconventional fringes.

  9. The health status of retired American football players: Super Bowl III revisited.

    Science.gov (United States)

    Nicholas, Stephen J; Nicholas, James A; Nicholas, Calvin; Diecchio, Jennifer R; McHugh, Malachy P

    2007-10-01

    Despite a perception that retired professional football players have poor health, there are little supporting data. Retired football players have poor health compared with age-matched population norms. Cross-sectional study; Level of evidence, 4. Thirty-six of 41 members of the 1969 Super Bowl winning team were contacted 35 years after that event (3 were deceased, and no contact information was available for 2). Players completed an SF-36 health survey and a medical history and football-specific questionnaire. Each player's football-related injury history before 1969 was documented from medical records. It was estimated that there was 80% power to detect a 10% difference in physical and mental health scores between the retired football players (age, 62 +/- 3 y) and population norms (n = 741) at an alpha level of 0.05. SF-36 scores for physical and mental health were not different from age-matched norms (physical health P = .69; mental health P = .49). The most prevalent medical conditions were arthritis (24 of 36 players), hypertension (13 of 36 players), and chronic low back pain (13 of 36 players). SF-36 physical health scores were 21% lower in players with arthritis (P football for 8.3 +/- 3.8 years, and 33 players (94%) reported having had "very fulfilling" (n = 24) or "somewhat fulfilling" (n = 9) careers. These professional football players had long and fulfilling careers with no apparent long-term detrimental effects on physical or mental health scores despite a high prevalence of arthritis.

  10. Galactic dust and extinction

    International Nuclear Information System (INIS)

    Lyngaa, G.

    1979-01-01

    The ratio R between visual extinction and colour excess, is slightly larger than 3 and does not vary much throughout our part of the Galaxy. The distribution of dust in the galactic plane shows, on the large scale, a gradient with higher colour excesses towards l=50 0 than towards l=230 0 . On the smaller scale, much of the dust responsible for extinction is situated in clouds which tend to group together. The correlation between positions of interstellar dust clouds and positions of spiral tracers seems rather poor in our Galaxy. However, concentrated dark clouds as well as extended regions of dust show an inclined distribution similar to the Gould belt of bright stars. (Auth.)

  11. Radioisotope dust pollution monitor

    International Nuclear Information System (INIS)

    Szepke, R.; Harasimczuk, J.; Dobrowiecki, J.

    1990-01-01

    Measuring principles and specification of two dust monitors: station-type AMIZ and portable-type PIK-10 for ambient air pollution are presented. The first one, a fully automatic instrument is destined for permanent monitoring of air pollution in preset sampling time from .25 to 24 hours. The second one was developed as a portable working model. Both instruments display their results in digital form in dust concentration units. (author)

  12. Coal dust symposium

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    This paper gives a report of the paper presented at the symposium held in Hanover on 9 and 10 February 1981. The topics include: the behaviour of dust and coal dust on combustion and explosion; a report on the accidents which occurred at the Laegerdorf cement works' coal crushing and drying plant; current safety requirements at coal crushing and drying plant; and coal crushing and drying. Four papers are individually abstracted. (In German)

  13. Dust devil generation

    International Nuclear Information System (INIS)

    G Onishchenko, O; A Pokhotelov, O; Horton, W; Stenflo, L

    2014-01-01

    The equations describing axi-symmetric nonlinear internal gravity waves in an unstable atmosphere are derived. A hydrodynamic model of a dust devil generation mechanism in such an atmosphere is investigated. It is shown that in an unstably stratified atmosphere the convective plumes with poloidal motion can grow exponentially. Furthermore, it is demonstrated that these convective plumes in an atmosphere with weak large scale toroidal motion are unstable with respect to three-dimensional dust devil generation. (papers)

  14. The Globalisation of migration

    OpenAIRE

    Milan Mesić

    2002-01-01

    The paper demonstrates that contemporary international migration is a constitutive part of the globalisation process. After defining the concepts of globalisation and the globalisation of migration, the author discusses six key themes, linking globalisation and international migration (“global cities”, the scale of migration; diversification of migration flows; globalisation of science and education; international migration and citizenship; emigrant communities and new identities). First, in ...

  15. Fractal dust grains in plasma

    International Nuclear Information System (INIS)

    Huang, F.; Peng, R. D.; Liu, Y. H.; Chen, Z. Y.; Ye, M. F.; Wang, L.

    2012-01-01

    Fractal dust grains of different shapes are observed in a radially confined magnetized radio frequency plasma. The fractal dimensions of the dust structures in two-dimensional (2D) horizontal dust layers are calculated, and their evolution in the dust growth process is investigated. It is found that as the dust grains grow the fractal dimension of the dust structure decreases. In addition, the fractal dimension of the center region is larger than that of the entire region in the 2D dust layer. In the initial growth stage, the small dust particulates at a high number density in a 2D layer tend to fill space as a normal surface with fractal dimension D = 2. The mechanism of the formation of fractal dust grains is discussed.

  16. Electrodynamic Dust Shield Demonstrator

    Science.gov (United States)

    Stankie, Charles G.

    2013-01-01

    The objective of the project was to design and manufacture a device to demonstrate a new technology developed by NASA's Electrostatics and Surface Physics Laboratory. The technology itself is a system which uses magnetic principles to remove regolith dust from its surface. This project was to create an enclosure that will be used to demonstrate the effectiveness of the invention to The Office of the Chief Technologist. ONE of the most important challenges of space exploration is actually caused by something very small and seemingly insignificant. Dust in space, most notably on the moon and Mars, has caused many unforeseen issues. Dirt and dust on Earth, while a nuisance, can be easily cleaned and kept at bay. However, there is considerably less weathering and erosion in space. As a result, the microscopic particles are extremely rough and abrasive. They are also electrostatically charged, so they cling to everything they make contact with. This was first noted to be a major problem during the Apollo missions. Dust would stick to the spacesuits, and could not be wiped off as predicted. Dust was brought back into the spacecraft, and was even inhaled by astronauts. This is a major health hazard. Atmospheric storms and other events can also cause dust to coat surfaces of spacecraft. This can cause abrasive damage to the craft. The coating can also reduce the effectiveness of thermal insulation and solar panels.' A group of engineers at Kennedy Space Center's Electrostatics and Surface Physics Laboratory have developed a new technology, called the Electrodynamic Dust Shield, to help alleviate these problems. It is based off of the electric curtain concept developed at NASA in 1967. "The EDS is an active dust mitigation technology that uses traveling electric fields to transport electrostatically charged dust particles along surfaces. To generate the traveling electric fields, the EDS consists of a multilayer dielectric coating with an embedded thin electrode grid

  17. The National Ocean Sciences Bowl: An Effective Model for Engaging High School Students in Ocean Science

    Science.gov (United States)

    Holloway, A. E.

    2016-02-01

    The National Ocean Sciences Bowl (NOSB) is an informal high school education program that engages students in ocean and environmental science and exposes them to the breadth of ocean-related careers. The NOSB strives to train the next generation of interdisciplinary capable scientists and build a STEM-literate society that harnesses the power of ocean and climate science to address environmental, economic, and societal issues. Through the NOSB, students not only learn scientific principles, but also apply them to compelling real-world problems. The NOSB provides a richer STEM education and exposes students to ocean science topics they may not otherwise study through classroom curriculum. A longitudinal study that began in 2007 has shown that NOSB participants have an enhanced interest in ocean-related hobbies and environmental stewardship and an increasing number of these students have remained in the STEM pipeline and workforce.While the NOSB is primarily an academic competition, it has evolved since its creation in 1998 to include a variety of practical and professional development components. One of the program enhancements, the Scientific Expert Briefing (SEB), gives students the opportunity to apply what they have studied and think critically about current and ongoing ocean science challenges. The SEB helps students connect their knowledge of ocean science with current and proposed policy initiatives. Students gain significant research, writing, and presentation skills, while enhancing their ability for collaboration and consensus building, all vital workforce skills. Ultimately, the SEB teaches students how to communicate complex scientific research into digestible information for decision-makers and the general public.This poster will examine the impact of the NOSB and its role in strengthening the workforce pipeline through a combination of independent learning, competition, and opportunities for communication skills development.

  18. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Kwok, S.

    1980-01-01

    A two-component dust model is suggested to explain the infrared emission from planetary nebulae. A cold dust component located in the extensive remnant of the red-giant envelope exterior to the visible nebula is responsible for the far-infrared emission. A ward dust component, which is condensed after the formation of the planetary nebula and confined within the ionized gas shell, emits most of the near- and mid-infrared radiation. The observations of NGC 7027 are shown to be consisten with such a model. The correlation of silicate emission in several planetary nebulae with an approximately +1 spectral index at low radio frequencies suggests that both the silicate and radio emissions originate from the remnant of the circumstellar envelope of th precursor star and are observable only while the planetary nebula is young. It is argued that oxygen-rich stars as well as carbon-rich stars can be progenitors of planetary nebulae

  19. Interstellar dust and extinction

    International Nuclear Information System (INIS)

    Mathis, J.S.

    1990-01-01

    It is noted that the term interstellar dust refers to materials with rather different properties, and that the mean extinction law of Seaton (1979) or Savage and Mathis (1979) should be replaced by the expression given by Cardelli et al. (1989), using the appropriate value of total-to-selective extinction. The older laws were appropriate for the diffuse ISM but dust in clouds differs dramatically in its extinction law. Dust is heavily processed while in the ISM by being included within clouds and cycled back into the diffuse ISM many times during its lifetime. Hence, grains probably reflect only a trace of their origin, although meteoritic inclusions with isotopic anomalies demonstrate that some tiny particles survive intact from a supernova origin to the present. 186 refs

  20. Dust control for draglines

    Energy Technology Data Exchange (ETDEWEB)

    Grad, P.

    2009-09-15

    Monitoring dust levels inside draglines reveals room for improvement in how filtration systems are used and maintained. The Australian firm BMT conducted a field test program to measure airflow parameters, dust fallout rates and dust concentrations, inside and outside the machine house, on four draglines and one shovel. The study involved computational fluid dynamics (CFD) simulations. The article describes how the tests were made and gives results. It was not possible to say which of the two main filtration systems currently used on Australian draglines - Dynavane or Floseps - performs better. It would appear that more frequent maintenance and cleaning would increase the overall filtration performance and systems could be susceptible to repeat clogging in a short time. 2 figs., 1 photos.

  1. DustEM: Dust extinction and emission modelling

    Science.gov (United States)

    Compiègne, M.; Verstraete, L.; Jones, A.; Bernard, J.-P.; Boulanger, F.; Flagey, N.; Le Bourlot, J.; Paradis, D.; Ysard, N.

    2013-07-01

    DustEM computes the extinction and the emission of interstellar dust grains heated by photons. It is written in Fortran 95 and is jointly developed by IAS and CESR. The dust emission is calculated in the optically thin limit (no radiative transfer) and the default spectral range is 40 to 108 nm. The code is designed so dust properties can easily be changed and mixed and to allow for the inclusion of new grain physics.

  2. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Rosenberg, M.

    2010-01-01

    The objective of our theoretical research under this grant over the past 3 years was to develop new understanding in a range of topics in the physics of dust-plasma interactions, with application to space and the laboratory. We conducted studies related to the physical properties of dust, waves and instabilities in both weakly coupled and strongly coupled dusty plasmas, and innovative possible applications. A major consideration in our choice of topics was to compare theory with experiments or observations, and to motivate new experiments, which we believe is important for developing this relatively new field. Our research is summarized, with reference to our list of journal publications.

  3. Outreach for Families and Girls- Astronomy at Outdoor Concerts and at Super Bowl or Halloween Star Parties

    Science.gov (United States)

    Lubowich, Donald A.

    2011-05-01

    Bring telescope to where the people are! Music and Astronomy Under the Stars (MAUS) is a NASA-funded as astronomy outreach program at community parks and music festivals (1000 - 25,000 people/event). While there have been many astronomy outreach activities and telescope observations at sidewalks and parks, this program targets a different audience - music lovers who are attending concerts in community parks or festivals. These music lovers who may not have visited science museums, planetariums, or star parties are exposed to telescope observations and astronomy information with no additional travel costs. MAUS includes solar observing, telescope observations including a live imaging system, an astronomical video, astronomy banners/posters, and hands-on activities. MAUS increased awareness, engagement, and interest in astronomy at classical, pop, rock, and ethnic music concerts. Since 2009 over 50,000 people have participated in these outreach activities including a significant number of families and young girls. In addition to concerts in local Long Island parks, there were MUAS events at Tanglewood (summer home of the Boston Symphony Orchestra), Jazz in Central Park, and Astronomy Night on the National Mall (co-sponsored by the White House Office of Science and Technology Policy). In 2011 MUAS will be expanded to include Ravinia (summer home of the Chicago Symphony Orchestra), the Newport Folk Festival, and the Bethel Woods Center for the Arts (site of the 1969 Woodstock festival). According to our survey results, music lovers became more informed about astronomy. Expanding Hofstra University's successful outreach programs, I propose the creation of a National Halloween Stars event targeting children and a National Super Bowl Star Party targeting girls, women, and the 2/3 of Americans who do not watch the Super Bowl. This can be combined with astronomers or amateur astronomers bringing telescopes to Super Bowl parties for football fans to stargaze during

  4. Control of harmful dust in coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, B; Bower, K; Mitchell, D

    1973-01-01

    This handbook consists of a series of short chapters devoted to: sources of airborne dust; dust standards and methods of sampling; dust prevention on mechanized faces; ventilation and dust extraction; distribution and use of water; dust control on mechanized faces; dust control in drivages and headings; drilling and shotfiring; dust control in transport; some outbye dust control techniques (hygroscopic salts, impingement curtains); water infusion; personal protective equipment. (CIS Abstr.)

  5. Dust evolution in protoplanetary disks

    OpenAIRE

    Gonzalez , Jean-François; Fouchet , Laure; T. Maddison , Sarah; Laibe , Guillaume

    2007-01-01

    6 pages, 5 figures, to appear in the Proceedings of IAU Symp. 249: Exoplanets: Detection, Formation and Dynamics (Suzhou, China); International audience; We investigate the behaviour of dust in protoplanetary disks under the action of gas drag using our 3D, two-fluid (gas+dust) SPH code. We present the evolution of the dust spatial distribution in global simulations of planetless disks as well as of disks containing an already formed planet. The resulting dust structures vary strongly with pa...

  6. Respirable versus inhalable dust sampling

    International Nuclear Information System (INIS)

    Hondros, J.

    1987-01-01

    The ICRP uses a total inhalable dust figure as the basis of calculations on employee lung dose. This paper was written to look at one aspect of the Olympic Dam dust situation, namely, the inhalable versus respirable fraction of the dust cloud. The results of this study will determine whether it is possible to use respirable dust figures, as obtained during routine monitoring to help in the calculations of employee exposure to internal radioactive contaminants

  7. Paleo-dust insights onto dust-climate interactions

    Science.gov (United States)

    Albani, S.; Mahowald, N. M.

    2017-12-01

    Mineral dust emissions are affected by changing climate conditions, and in turn dust impacts the atmospheric radiation budget, clouds and biogeochemical cycles. Climate and public health dust-related issues call for attention on the fate of the dust cycle in the future, and the representation of the dust cycle is now part of the strategy of the Paleoclimate Modelling Intercomparison Project phase 4 and the Coupled Model Intercomparison Project phase 6 (PMIP4-CMIP6). Since mineral aerosols are one of the most important natural aerosols, understanding past dust responses to climate in the paleoclimate will allow us to better understand mineral aerosol feedbacks with climate and biogeochemistry in the Anthropocene. Modern observations and paleoclimate records offer the possibility of multiple, complementary views on the global dust cycle, and allow to validate and/or constrain the numerical representation of dust in climate and Earth system models. We present our results from a set of simulations with the Community Earth System Model for different climate states, including present and past climates such as the pre-industrial, the mid-Holocene and the Last Glacial Maximum. A set of simulations including a prognostic dust cycle was thoroughly compared with a wide set of present day observations from different platforms and regions, in order to realistically constrain the magnitude of dust load, surface concentration, deposition, optical properties, and particle size distributions. The magnitude of emissions for past climate regimes was constrained based on compilations of paleodust mass accumulation rates and size distributions, as well as based on information on dust provenance. The comparison with a parallel set of simulations without dust allows estimating the impacts of dust on surface climate. We analyze impacts of dust on the mean and variability of surface temperature and precipitation in each climate state, as well as the impacts that changing dust emissions had

  8. Erosion of dust aggregates

    NARCIS (Netherlands)

    Seizinger, A.; Krijt, S.; Kley, W.

    2013-01-01

    Aims: The aim of this work is to gain a deeper insight into how much different aggregate types are affected by erosion. Especially, it is important to study the influence of the velocity of the impacting projectiles. We also want to provide models for dust growth in protoplanetary disks with simple

  9. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Rosenberg, Marelene

    2005-01-01

    Our theoretical research on dust-plasma interactions has concentrated on three main areas: (a)studies of grain charging and applications; (b) waves and instabilities in weakly correlated dusty plasma with applications to space and laboratory plasmas; (c) waves in strongly coupled dusty plasmas.

  10. From dust to life

    Science.gov (United States)

    Wickramasinghe, Chandra

    After initially challenging the dirty-ice theory of interstellar grains, Fred Hoyle and the present author proposed carbon (graphite) grains, mixtures of refractory grains, organic polymers, biochemicals and finally bacterial grains as models of interstellar dust. The present contribution summarizes this trend and reviews the main arguments supporting a modern version of panspermia.

  11. Aspergillus candidus: a respiratory hazard associated with grain dust.

    Science.gov (United States)

    Krysinska-Traczyk, E; Dutkiewicz, J

    2000-01-01

    The concentration of Aspergillus candidus in samples of grain dust and of air polluted with grain dust was found to be large (respectively 3.0 x 10(5) - 3.0 x 10(9) cfu/g and 5.0 x 10(3) - 6.47 x 10(5) cfu/m(3)) and proved to be significantly greater compared to samples of other organic dusts (pgrain workers reacted significantly more frequently to extract of A. candidus in the leukocyte migration inhibition test (pdusts. It was concluded that Aspergillus candidus, because of its common occurrence and strong immunomodulating properties, poses an important occupational hazard for grain handling workers

  12. Reconstruction of a Phreatic Explosion from Block Dispersion Modeling at King's Bowl, Idaho

    Science.gov (United States)

    Kobs-Nawotniak, S. E.; Sears, D. W. G.; Hughes, S. S.; Borg, C.; Sears, H.; Skok, J. R.; Elphic, R. C.; Lim, D. S. S.; Heldmann, J. L.; Haberle, C. W.; Guy, H.; Kobayashi, L.; Garry, B.; Neish, C.; Kim, K. J.

    2014-12-01

    King's Bowl (KB), located in Idaho's eastern Snake River Plain, was formed by a phreatic blast through a mostly-congealed lava lake. Blocks up to ~2m diameter were ejected from the vent to form a ballistic ejecta blanket extending radially more than 100m. The blocks on the western side of the KB fissure are extraordinarily well exposed, as the fine fraction was blown eastward by ambient winds during the explosion. We present preliminary modeling results using the western ballistic blocks of KB to calculate the energy of the eruption, and the water volume necessary to create the blast. This work is presented in conjunction with two other 2014 AGU conference abstracts submitted by NASA SSERVI funded FINESSE (Field Investigations to Enable Solar System Science and Exploration) team members: Hughes et al., which introduces the geology of KB and Sears et al., which discusses field observation and data trends. Results of this research are extensible to steam-driven pits on other solar system bodies, including those observed on Mars, Phobos, Deimos, and the asteroids. Over 600 blocks ranging from .2 to 2m in diameter were mapped using differential GPS and measured for 3 axial lengths and vesicularity. Mass calculations were corrected using a scaling factor determined from measurements of 100 blocks at KB, coupled with targeted density measurements. The dispersed block trajectories were modeled using a fourth order Runge-Kutta solution of the equations of motion to calculate suites of possible ejection speeds and angles. The resulting characteristic vent velocities were used to calculate the kinetic energy necessary to evacuate the crater at KB; energy required for fragmentation is neglected at this time. Total mass in the kinetic energy calculations was calculated by two separate methods: 1) current volume expression of the KB crater and 2) an additive solution of the ejecta field as determined from radial transect surveys. From the kinetic energy we calculated the

  13. Long-Term Effects on Graphene Supercapacitors of Using a Zirconia Bowl and Zirconia Balls for Ball-Mill mixing of Active Materials

    Science.gov (United States)

    Song, Dae-Hoon; Kim, Jin-Young; Kahng, Yung Ho; Cho, Hoonsung; Kim, Eung-Sam

    2018-04-01

    Improving the energy storage performance of supercapacitor electrodes based on reduced graphene oxide (RGO) is one of the main subjects in this research field. However, when a zirconia bowl and zirconia balls were used for ball-mill mixing of the active materials for RGO supercapacitors, the energy storage performance deteriorated over time. Our study revealed that the source of the problem was the inclusion of zirconia bits from abrasion of the bowl and the balls during the ballmill mixing, which increased during a period of 1 year. We probed two solutions to this problem: 1) hydrofluoric (HF) acid treatment of the RGO supercapacitors and 2) use of a tempered steel bowl and tempered steel balls for the mixing. For both cases, the energy storage performance was restored to near the initial level, showing a specific capacitance ( C sp ) of 200 F/g. Our results should lead to progress in research on RGO supercapacitors.

  14. Modelling dust transport in tokamaks

    International Nuclear Information System (INIS)

    Martin, J.D.; Martin, J.D.; Bacharis, M.; Coppins, M.; Counsell, G.F.; Allen, J.E.; Counsell, G.F.

    2008-01-01

    The DTOKS code, which models dust transport through tokamak plasmas, is described. The floating potential and charge of a dust grain in a plasma and the fluxes of energy to and from it are calculated. From this model, the temperature of the dust grain can be estimated. A plasma background is supplied by a standard tokamak edge modelling code (B2SOLPS5.0), and dust transport through MAST (the Mega-Amp Spherical Tokamak) and ITER plasmas is presented. We conclude that micron-radius tungsten dust can reach the separatrix in ITER. (authors)

  15. Codification of scan path parameters and development of perimeter scan strategies for 3D bowl-shaped laser forming

    Science.gov (United States)

    Tavakoli, A.; Naeini, H. Moslemi; Roohi, Amir H.; Gollo, M. Hoseinpour; Shahabad, Sh. Imani

    2018-01-01

    In the 3D laser forming process, developing an appropriate laser scan pattern for producing specimens with high quality and uniformity is critical. This study presents certain principles for developing scan paths. Seven scan path parameters are considered, including: (1) combined linear or curved path; (2) type of combined linear path; (3) order of scan sequences; (4) the position of the start point in each scan; (5) continuous or discontinuous scan path; (6) direction of scan path; and (7) angular arrangement of combined linear scan paths. Regarding these path parameters, ten combined linear scan patterns are presented. Numerical simulations show continuous hexagonal, scan pattern, scanning from outer to inner path, is the optimized. In addition, it is observed the position of the start point and the angular arrangement of scan paths is the most effective path parameters. Also, further experimentations show four sequences due to creat symmetric condition enhance the height of the bowl-shaped products and uniformity. Finally, the optimized hexagonal pattern was compared with the similar circular one. In the hexagonal scan path, distortion value and standard deviation rather to edge height of formed specimen is very low, and the edge height despite of decreasing length of scan path increases significantly compared to the circular scan path. As a result, four-sequence hexagonal scan pattern is proposed as the optimized perimeter scan path to produce bowl-shaped product.

  16. Public Health Surveillance Strategies for Mass Gatherings: Super Bowl XLIX and Related Events, Maricopa County, Arizona, 2015.

    Science.gov (United States)

    Ayala, Aurimar; Berisha, Vjollca; Goodin, Kate; Pogreba-Brown, Kristen; Levy, Craig; McKinney, Benita; Koski, Lia; Imholte, Sara

    2016-01-01

    Super Bowl XLIX took place on February 1, 2015, in Glendale, Arizona. In preparation for this event and associated activities, the Maricopa County Department of Public Health (MCDPH) developed methods for enhanced surveillance, situational awareness, and early detection of public health emergencies. Surveillance strategies implemented from January 22 to February 6, 2015, included enhanced surveillance alerts; animal disease surveillance; review of NFL clinic visits; syndromic surveillance for emergency room visits, urgent care facilities, and hotels; real-time onsite syndromic surveillance; all-hazards mortality surveillance; emergency medical services surveillance, review of poison control center reports; media surveillance; and aberration detection algorithms for notifiable diseases. Surveillance results included increased influenzalike illness activity reported from urgent care centers and a few influenza cases reported in the NFL clinic. A cyanide single event exposure was investigated and determined not to be a public health threat. Real-time field syndromic surveillance documented minor injuries at all events and sporadic cases of gastrointestinal and neurological (mostly headaches) disease. Animal surveillance reports included a cat suspected of carrying plague and tularemia and an investigation of highly pathogenic avian influenza in a backyard chicken flock. Laboratory results in both instances were negative. Aberration detection and syndromic surveillance detected an increase in measles reports associated with a Disneyland exposure, and syndromic surveillance was used successfully during this investigation. Coordinated enhanced epidemiologic surveillance during Super Bowl XLIX increased the response capacity and preparedness of MCDPH to make informed decisions and take public health actions in a timely manner during these mass gathering events.

  17. Microbial Content of “Bowl Water” Used for Communal Handwashing in Preschools within Accra Metropolis, Ghana

    Directory of Open Access Journals (Sweden)

    Patience B. Tetteh-Quarcoo

    2016-01-01

    Full Text Available Objective. This study aimed at determining the microbial content of “bowl water” used for communal handwashing in preschools within the Accra Metropolis. Method. Six (6 preschools in the Accra Metropolis were involved in the study. Water samples and swabs from the hands of the preschool children were collected. The samples were analysed and tested for bacteria, fungi, parasites, and rotavirus. Results. Eight different bacteria, two different parasites, and a fungus were isolated while no rotavirus was detected. Unlike the rest of the microbes, bacterial isolates were found among samples from all the schools, with Staphylococcus species being the most prevalent (40.9%. Out of the three schools that had parasites in their water, two of them had Cryptosporidium parvum. The fungus isolated from two out of the six schools was Aspergillus niger. All bacteria isolated were found to be resistant to cotrimoxazole, ciprofloxacin, and ampicillin and susceptible to amikacin and levofloxacin. Conclusion. Although handwashing has the ability to get rid of microbes, communal handwashing practices using water in bowls could be considered a possible transmission route and may be of public concern.

  18. MODELING DUST EMISSION OF HL TAU DISK BASED ON PLANET–DISK INTERACTIONS

    International Nuclear Information System (INIS)

    Jin, Sheng; Ji, Jianghui; Li, Shengtai; Li, Hui; Isella, Andrea

    2016-01-01

    We use extensive global two-dimensional hydrodynamic disk gas+dust simulations with embedded planets, coupled with three-dimensional radiative transfer calculations, to model the dust ring and gap structures in the HL Tau protoplanetary disk observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). We include the self-gravity of disk gas and dust components and make reasonable choices of disk parameters, assuming an already settled dust distribution and no planet migration. We can obtain quite adequate fits to the observed dust emission using three planets with masses of 0.35, 0.17, and 0.26 M Jup at 13.1, 33.0, and 68.6 AU, respectively. Implications for the planet formation as well as the limitations of this scenario are discussed

  19. Dust storm, northern Mexico

    Science.gov (United States)

    1983-01-01

    This large dust storm along the left side of the photo, covers a large portion of the state of Coahuila, Mexico (27.5N, 102.0E). The look angle of this oblique photo is from the south to the north. In the foreground is the Sierra Madre Oriental in the states Coahuila and Nuevo Leon with the Rio Grande River, Amistad Reservoir and Texas in the background.

  20. MANAGING MIGRATION: TURKISH PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    İhsan GÜLAY

    2018-04-01

    Full Text Available Conducting migration studies is of vital importance to Turkey, a country which has been experiencing migration throughout history due to its “open doors policy”. The objective of this study is to evaluate the strategic management of migration in Turkey in order to deal with the issue of migration. The main focus of the study is Syrian migrants who sought refuge in Turkey due to the civil war that broke out in their country in April 2011. This study demonstrates the policies and processes followed by Turkey for Syrian migration flow in terms of the social acceptance and harmonisation of the migrants within a democratic environment. The study addresses some statistical facts and issues related to Syrian migration as it has become an integral part of daily life in Turkey. The study also reviews how human rights are protected in the migration process. The study will provide insights for developing sound strategic management policies for the migration issue.

  1. Migration and revolution

    Directory of Open Access Journals (Sweden)

    Nando Sigona

    2012-06-01

    Full Text Available The Arab Spring has not radically transformed migration patterns in the Mediterranean, and the label ‘migration crisis’ does not do justice to the composite and stratified reality.

  2. Dust acoustic shock wave at high dust density

    International Nuclear Information System (INIS)

    Ghosh, Samiran; Sarkar, Susmita; Khan, Manoranjan; Avinash, K.; Gupta, M. R.

    2003-01-01

    Dust acoustic (DA) shock wave at high dust density, i.e., the dust electroacoustic (DEA) or dust Coulomb (DC) shock wave has been investigated incorporating the nonadiabatic dust charge variation. The nonlinear DEA (DC) shock wave is seen to be governed by the Korteweg-de Vries Burger equation, in which the Burger term is proportional to the nonadiabaticity generated dissipation. It is seen that the shock strength decreases but after reaching minimum, it increases as the dust space charge density |q d n d | increases and the shock strength of DA wave is greater than that of DEA (DC) wave. Moreover the DEA (DC) shock width increases appreciably with increase mass m i of the ion component of the dusty plasma but for DA shock wave the effect is weak

  3. Dust, Climate, and Human Health

    Science.gov (United States)

    Maynard, Nancy G.

    2003-01-01

    Air pollution from both natural and anthropogenic causes is considered to be one of the most serious world-wide environment-related health problems, and is expected to become worse with changes in the global climate. Dust storms from the atmospheric transport of desert soil dust that has been lifted and carried by the winds - often over significant distances - have become an increasingly important emerging air quality issue for many populations. Recent studies have shown that the dust storms can cause significant health impacts from the dust itself as well as the accompanying pollutants, pesticides, metals, salt, plant debris, and other inorganic and organic materials, including viable microorganisms (bacteria, viruses and fungi). For example, thousands of tons of Asian desert sediments, some containing pesticides and herbicides from farming regions, are commonly transported into the Arctic during dust storm events. These chemicals have been identified in animal and human tissues among Arctic indigenous populations. Millions of tons of airborne desert dust are being tracked by satellite imagery, which clearly shows the magnitude as well as the temporal and spatial variability of dust storms across the "dust belt" regions of North Africa, the Middle East, and China. This paper summarizes the most recent findings on the effects of airborne desert dust on human health as well as potential climate influences on dust and health.

  4. Population, migration and urbanization.

    Science.gov (United States)

    1982-06-01

    Despite recent estimates that natural increase is becoming a more important component of urban growth than rural urban transfer (excess of inmigrants over outmigrants), the share of migration in the total population growth has been consistently increasing in both developed and developing countries. From a demographic perspective, the migration process involves 3 elements: an area of origin which the mover leaves and where he or she is considered an outmigrant; the destination or place of inmigration; and the period over which migration is measured. The 2 basic types of migration are internal and international. Internal migration consists of rural to urban migration, urban to urban migration, rural to rural migration, and urban to rural migration. Among these 4 types of migration various patterns or processes are followed. Migration may be direct when the migrant moves directly from the village to the city and stays there permanently. It can be circular migration, meaning that the migrant moves to the city when it is not planting season and returns to the village when he is needed on the farm. In stage migration the migrant makes a series of moves, each to a city closer to the largest or fastest growing city. Temporary migration may be 1 time or cyclical. The most dominant pattern of internal migration is rural urban. The contribution of migration to urbanization is evident. For example, the rapid urbanization and increase in urban growth from 1960-70 in the Republic of Korea can be attributed to net migration. In Asia the largest component of the population movement consists of individuals and groups moving from 1 rural location to another. Recently, because urban centers could no longer absorb the growing number of migrants from other places, there has been increased interest in the urban to rural population redistribution. This reverse migration also has come about due to slower rates of employment growth in the urban centers and improved economic opportunities

  5. Parameterizing the interstellar dust temperature

    Science.gov (United States)

    Hocuk, S.; Szűcs, L.; Caselli, P.; Cazaux, S.; Spaans, M.; Esplugues, G. B.

    2017-08-01

    The temperature of interstellar dust particles is of great importance to astronomers. It plays a crucial role in the thermodynamics of interstellar clouds, because of the gas-dust collisional coupling. It is also a key parameter in astrochemical studies that governs the rate at which molecules form on dust. In 3D (magneto)hydrodynamic simulations often a simple expression for the dust temperature is adopted, because of computational constraints, while astrochemical modelers tend to keep the dust temperature constant over a large range of parameter space. Our aim is to provide an easy-to-use parametric expression for the dust temperature as a function of visual extinction (AV) and to shed light on the critical dependencies of the dust temperature on the grain composition. We obtain an expression for the dust temperature by semi-analytically solving the dust thermal balance for different types of grains and compare to a collection of recent observational measurements. We also explore the effect of ices on the dust temperature. Our results show that a mixed carbonaceous-silicate type dust with a high carbon volume fraction matches the observations best. We find that ice formation allows the dust to be warmer by up to 15% at high optical depths (AV> 20 mag) in the interstellar medium. Our parametric expression for the dust temperature is presented as Td = [ 11 + 5.7 × tanh(0.61 - log 10(AV) ]χuv1/5.9, where χuv is in units of the Draine (1978, ApJS, 36, 595) UV field.

  6. Analysis of melamine migration from melamine food contact articles.

    Science.gov (United States)

    Chik, Z; Haron, D E Mohamad; Ahmad, E D; Taha, H; Mustafa, A M

    2011-01-01

    Migration of melamine has been determined for 41 types of retail melamine-ware products in Malaysia. This study was initiated by the Ministry of Health, Malaysia, in the midst of public anxiety on the possibility of melamine leaching into foods that come into contact with the melamine-ware. Thus, the objective of this study was to investigate the level of melamine migration in melamine utensils available on the market. Samples of melamine tableware, including cups and plates, forks and spoons, tumblers, bowls, etc., were collected from various retail outlets. Following the test guidelines for melamine migration set by the European Committee for Standardisation (CEN 2004) with some modifications, the samples were exposed to two types of food simulants (3% acetic acid and distilled water) at three test conditions (25°C (room temperature), 70 and 100°C) for 30 min. Melamine analysis was carried out using LC-MS/MS with a HILIC column and mobile phase consisting of ammonium acetate/formic acid (0.05%) in water and ammonium acetate/formic acid (0.05%) in acetonitrile (95 : 5, v/v). The limit of quantification (LOQ) was 5 ng/ml. Melamine migration was detected from all samples. For the articles tested with distilled water, melamine migration were [median (interquartile range)] 22.2 (32.6), 49.3 (50.9), 84.9 (89.9) ng/ml at room temperature (25°C), 70 and 100°C, respectively. In 3% acetic acid, melamine migration was 31.5 (35.7), 81.5 (76.2), 122.0 (126.7) ng/ml at room temperature (25°C), 70 and 100°C, respectively. This study suggests that excessive heat and acidity may directly affect melamine migration from melamine-ware products. However the results showed that melamine migration in the tested items were well below the specific migration limit (SML) of 30 mg/kg (30,000 ng/ml) set out in European Commission Directive 2002/72/EC.

  7. [Internal migration studies].

    Science.gov (United States)

    Stpiczynski, T

    1986-10-01

    Recent research on internal migration in Poland is reviewed. The basic sources of data, consisting of censuses or surveys, are first described. The author discusses the relationship between migration studies and other sectors of the national economy, and particularly the relationship between migration and income.

  8. Dust in H II regions

    International Nuclear Information System (INIS)

    Isobe, S.

    1977-01-01

    Several pieces of evidence indicate that H II regions may contain dust: 1) the continuum light scattered by dust grains (O'Dell and Hubbard, 1965), 2) thermal radiation from dust grains at infrared wavelengths (Ney and Allen, 1969), 3) the abnormal helium abundance in some H II regions (Peimbert and Costero, 1969), etc. Although observations of the scattered continuum suggest that the H II region cores may be dust-free, dust grains and gas must be well mixed in view of the infrared observations. This difficulty may be solved by introducing globules with sizes approximately 0.001 pc. These globules and the molecular clouds adjacent to H II regions are the main sources supplying dust to H II regions. (Auth.)

  9. Large Aperture Electrostatic Dust Detector

    International Nuclear Information System (INIS)

    Skinner, C.H.; Hensley, R.; Roquemore, A.L.

    2007-01-01

    Diagnosis and management of dust inventories generated in next-step magnetic fusion devices is necessary for their safe operation. A novel electrostatic dust detector, based on a fine grid of interlocking circuit traces biased to 30 or 50 v has been developed for the detection of dust particles on remote surfaces in air and vacuum environments. Impinging dust particles create a temporary short circuit and the resulting current pulse is recorded by counting electronics. Up to 90% of the particles are ejected from the grid or vaporized suggesting the device may be useful for controlling dust inventories. We report measurements of the sensitivity of a large area (5x5 cm) detector to microgram quantities of dust particles and review its applications to contemporary tokamaks and ITER.

  10. Photoelectric charging of dust grains

    International Nuclear Information System (INIS)

    Ignatov, A. M.

    2009-01-01

    Photoemission from the surface of a dust grain in vacuum is considered. It is shown that the cutoff in the energy spectrum of emitted electrons leads to the formation of a steady-state electron cloud. The equation describing the distribution of the electric potential in the vicinity of a dust grain is solved numerically. The dust grain charge is found as a function of the grain size.

  11. Dust in cosmic plasma environments

    International Nuclear Information System (INIS)

    Mendis, D.A.

    1979-01-01

    Cosmic dust is invariably immersed in a plasma and a radiative environment. Consequently, it is charged to some electrostatic potential which depends on the properties of the environment as well as the nature of the dust. This charging affects the physical and dynamical properties of the dust. In this paper the basic aspects of this dust-plasma interaction in several cosmic environments - including planetary magnetospheres, the heliosphere and the interstellar medium - are discussed. The physical and dynamical consequences of the interaction, as well as the pertinent observational evidence, are reviewed. Finally, the importance of the surface charge during the condensation process in plasma environments is stressed. (Auth.)

  12. Li and Na storage behavior of bowl-like hollow Co3O4 microspheres as an anode material for lithium-ion and sodium-ion batteries

    International Nuclear Information System (INIS)

    Wen, Jian-Wu; Zhang, Da-Wei; Zang, Yong; Sun, Xin; Cheng, Bin; Ding, Chu-Xiong; Yu, Yan; Chen, Chun-Hua

    2014-01-01

    Highlights: • A unique bowl-like hollow spherical Co 3 O 4 structure is prepared through a simple, low-cost and mass-yield method. • Such a bowl-like hollow Co 3 O 4 microsphere demonstrates extraordinary rate and cycling performance for Li-storage. • The sodium-storage behavior of Co 3 O 4 is investigated for the first time. - Abstract: Bowl-like hollow Co 3 O 4 microspheres are prepared via a simple and low-cost route by thermally treating Co-containing resorcinol-formaldehyde composites gel in air. Scanning electron microscopy, transmission electron microscope and N 2 adsorption-desorption measurements demonstrate that these bowl-like hollow Co 3 O 4 microspheres are composed of hollow inner cavities and outer shell walls (70 nm thickness), on which a considerable amount of mesopores centered around 5-17 nm size are distributed. When employed as the anode material for lithium-ion batteries, these bowl-like hollow Co 3 O 4 microspheres exhibit extraordinary cycling performance (111% retention after 50 cycles owing to capacity rise), fairly high rate capacity (650 mAh g −1 at 5 C) and enhanced lithium storage capacity. Meanwhile, the Na-storage behavior of Co 3 O 4 as an anode material of Na-ion batteries is initially investigated based on such a hollow structure and it exhibits similar feature of discharge/charge profiles and a high initial discharge capacity but relatively moderate capacity retention compared with the Li-storage performance

  13. Gravitational radiation from dust

    International Nuclear Information System (INIS)

    Isaacson, R.A.; Welling, J.S.; Winicour, J.

    1985-01-01

    A dust cloud is examined within the framework of the general relativistic characteristic initial value problem. Unique gravitational initial data are obtained by requiring that the space-time be quasi-Newtonian. Explicit calculations of metric and matter fields are presented, which include all post-Newtonian corrections necessary to discuss the major physical properties of null infinity. These results establish a curved space version of the Einstein quadrupole formula, in the form ''news function equals third time derivative of transverse quadrupole moment,'' for this system. However, these results imply that some weakened notion of asymptotic flatness is necessary for the description of quasi-Newtonian systems

  14. Dust coagulation in ISM

    Science.gov (United States)

    Chokshi, Arati; Tielens, Alexander G. G. M.; Hollenbach, David

    1989-01-01

    Coagulation is an important mechanism in the growth of interstellar and interplanetary dust particles. The microphysics of the coagulation process was theoretically analyzed as a function of the physical properties of the coagulating grains, i.e., their size, relative velocities, temperature, elastic properties, and the van der Waal interaction. Numerical calculations of collisions between linear chains provide the wave energy in individual particles and the spectrum of the mechanical vibrations set up in colliding particles. Sticking probabilities are then calculated using simple estimates for elastic deformation energies and for the attenuation of the wave energy due to absorption and scattering processes.

  15. Dust confinement and dust acoustic waves in a magnetized plasma

    Science.gov (United States)

    Piel, A.

    2005-10-01

    Systematic laboratory experiments on dust acoustic waves require the confinement of dust particles. Here we report on new experiments in a magnetized plasma region in front of an additional positively biased disk electrode in a background plasma which is generated in argon at 27MHz between a disk and grid electrode. The plasma diffuses through the grid along the magnetic field. The three-dimensional dust distribution is measured with a horizontal sheet of laser light and a CCD camera, which are mounted on a vertical translation stage. Depending on magnetic field and discharge current, cigar or donut-shaped dust clouds are generated, which tend to rotate about the magnetic field direction. Measurements with emissive probes show that the axial confinement of dust particles with diameters between 0.7-2 μm is achieved by a balance of ion-drag force and electric field force. Dust levitation and radial confinement is due to a strong radial electric field. Dust acoustic waves are destabilized by the ion flow or can be stimulated by a periodic bias on the disk electrode. The observed wave dispersion is compared with fluid and kinetic models of the dust acoustic wave.

  16. Gravimetric dust sampling for control purposes and occupational dust sampling.

    CSIR Research Space (South Africa)

    Unsted, AD

    1997-02-01

    Full Text Available Prior to the introduction of gravimetric dust sampling, konimeters had been used for dust sampling, which was largely for control purposes. Whether or not absolute results were achievable was not an issue since relative results were used to evaluate...

  17. Of data and dust

    CERN Multimedia

    Stephanie Hills

    2016-01-01

    The traditional image of an archive is one of dusty old boxes, books and papers. When your archive is digital, dust spells disaster. An innovative environmental sensor designed and built by a CERN IT specialist has become an essential element in the Laboratory’s data-preservation strategy.   The novel air particle monitoring sensor designed by CERN's Julien Leduc. CERN’s archive holds more than 130 petabytes of data from past and present high-energy physics experiments. Some of it is 40 years old, most of it needs to be kept forever, and all of it is held on tape cartridges (over 20,000 of them). The cartridges are held inside tape libraries with robotic arms that load them into tape drives where they can be read and written. Tape cartridges have many advantages over other data storage media, notably cost and long-term reliability, but topping the list of drawbacks is their vulnerability to contamination from airborne dust particles; a tiny piece of g...

  18. Radionuclides in house dust

    Energy Technology Data Exchange (ETDEWEB)

    Fry, F A; Green, N; Dodd, N J; Hammond, D J

    1985-04-01

    Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate authorising Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, although radionuclides originating rom the BNFL site can be detected in house dust, this source of contamination is a negligible route of exposure for members of the public in West Cumbria. This report presents the results of the Board's study of house dust in twenty homes in Cumbria during the spring and summer of 1984. A more intensive investigation is being carried out by Imperial College. (author)

  19. Health hazards of cement dust

    International Nuclear Information System (INIS)

    Meo, Sultan A.

    2004-01-01

    ven in the 21st century, millions of people are working daily in a dusty environment. They are exposed to different types of health hazards such as fume, gases and dust, which are risk factors in developing occupational disease. Cement industry is involved in the development of structure of this advanced and modern world but generates dust during its production. Cement dust causes lung function impairment, chronic obstructive lung disease, restrictive lung disease, pneumoconiosis and carcinoma of the lungs, stomach and colon. Other studies have shown that cement dust may enter into the systemic circulation and thereby reach the essentially all the organs of body and affects the different tissues including heart, liver, spleen, bone, muscles and hairs and ultimately affecting their micro-structure and physiological performance. Most of the studies have been previously attempted to evaluate the effects of cement dust exposure on the basis of spirometry or radiology, or both. However, collective effort describing the general effects of cement dust on different organ and systems in humans or animals, or both has not been published. Therefore, the aim of this review is to gather the potential toxic effects of cement dust and to minimize the health risks in cement mill workers by providing them with information regarding the hazards of cement dust. (author)

  20. Dust forecasting system in JMA

    International Nuclear Information System (INIS)

    Mikami, M; Tanaka, T Y; Maki, T

    2009-01-01

    JMAs dust forecasting information, which is based on a GCM dust model, is presented through the JMA website coupled with nowcast information. The website was updated recently and JMA and MOE joint 'KOSA' website was open from April 2008. Data assimilation technique will be introduced for improvement of the 'KOSA' information.

  1. Dust in flowing magnetized plasma

    International Nuclear Information System (INIS)

    Pandey, Birendra P.; Samarian, Alex A.; Vladimirov, Sergey V.

    2009-01-01

    Plasma flows occur in almost every laboratory device and interactions of flowing plasmas with near-wall impurities and/or dust significantly affects the efficiency and lifetime of such devices. The charged dust inside the magnetized flowing plasma moves primarily under the influence of the plasma drag and electric forces. Here, the charge on the dust, plasma potential, and plasma density are calculated self-consistently. The electrons are assumed non-Boltzmannian and the effect of electron magnetization and electron-atom collisions on the dust charge is calculated in a self-consistent fashion. For various plasma magnetization parameters viz. the ratio of the electron and ion cyclotron frequencies to their respective collision frequencies, plasma-atom and ionization frequencies, the evolution of the plasma potential and density in the flow region is investigated. The variation of the dust charge profile is shown to be a sensitive function of plasma parameters. (author)

  2. Radon depth migration

    International Nuclear Information System (INIS)

    Hildebrand, S.T.; Carroll, R.J.

    1993-01-01

    A depth migration method is presented that used Radon-transformed common-source seismograms as input. It is shown that the Radon depth migration method can be extended to spatially varying velocity depth models by using asymptotic ray theory (ART) to construct wavefield continuation operators. These operators downward continue an incident receiver-array plane wave and an assumed point-source wavefield into the subsurface. The migration velocity model is constrain to have longer characteristic wavelengths than the dominant source wavelength such that the ART approximations for the continuation operators are valid. This method is used successfully to migrate two synthetic data examples: (1) a point diffractor, and (2) a dipping layer and syncline interface model. It is shown that the Radon migration method has a computational advantage over the standard Kirchhoff migration method in that fewer rays are computed in a main memory implementation

  3. Migration into art

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    This book addresses a topic of increasing importance to artists, art historians and scholars of cultural studies, migration studies and international relations: migration as a profoundly transforming force that has remodelled artistic and art institutional practices across the world. It explores...... contemporary art's critical engagement with migration and globalisation as a key source for improving our understanding of how these processes transform identities, cultures, institutions and geopolitics. The author explores three interwoven issues of enduring interest: identity and belonging, institutional...

  4. Dust in protoplanetary disks: observations*

    Directory of Open Access Journals (Sweden)

    Waters L.B.F.M.

    2015-01-01

    Full Text Available Solid particles, usually referred to as dust, are a crucial component of interstellar matter and of planet forming disks surrounding young stars. Despite the relatively small mass fraction of ≈1% (in the solar neighborhood of our galaxy; this number may differ substantially in other galaxies that interstellar grains represent of the total mass budget of interstellar matter, dust grains play an important role in the physics and chemistry of interstellar matter. This is because of the opacity dust grains at short (optical, UV wavelengths, and the surface they provide for chemical reactions. In addition, dust grains play a pivotal role in the planet formation process: in the core accretion model of planet formation, the growth of dust grains from the microscopic size range to large, cm-sized or larger grains is the first step in planet formation. Not only the grain size distribution is affected by planet formation. Chemical and physical processes alter the structure and chemical composition of dust grains as they enter the protoplanetary disk and move closer to the forming star. Therefore, a lot can be learned about the way stars and planets are formed by observations of dust in protoplanetary disks. Ideally, one would like to measure the dust mass, the grain size distribution, grain structure (porosity, fluffiness, the chemical composition, and all of these as a function of position in the disk. Fortunately, several observational diagnostics are available to derive constrains on these quantities. In combination with rapidly increasing quality of the data (spatial and spectral resolution, a lot of progress has been made in our understanding of dust evolution in protoplanetary disks. An excellent review of dust evolution in protoplanetary disks can be found in Testi et al. (2014.

  5. Regional Redistribution and Migration

    DEFF Research Database (Denmark)

    Manasse, Paolo; Schultz, Christian

    We study a model with free migration between a rich and a poor region. Since there is congestion, the rich region has an incentive to give the poor region a transfer in order to reduce immigration. Faced with free migration, the rich region voluntarily chooses a transfer, which turns out...... to be equal to that a social planner would choose. Provided migration occurs in equilibrium, this conclusion holds even in the presence of moderate mobility costs. However, large migration costs will lead to suboptimal transfers in the market solution...

  6. COAL DUST EMISSION PROBLEM

    Directory of Open Access Journals (Sweden)

    M. M. Biliaiev

    2016-12-01

    Full Text Available Purpose. The article aims to develop 2D numerical models for the prediction of atmospheric pollution during transportation of coal in the railway car, as well as the ways to protect the environment and the areas near to the mainline from the dust emission due to the air injection installation. Methodology. To solve this problem there were developed numerical models based on the use of the equations of motion of an inviscid incompressible fluid and mass transfer. For the numerical integration of the transport equation of the pollutant the implicit alternating-triangular difference scheme was used. For numerical integration of the 2D equation for the velocity potential the method of total approximation was used. The developed numerical models are the basis of established software package. On the basis of the constructed numerical models it was carried out a computational experiment to assess the level of air pollution when transporting bulk cargo by rail when the railway car has the air injection. Findings. 2D numerical models that belong to the class «diagnostic models» were developed. These models take into account the main physical factors affecting the process of dispersion of dust pollution in the atmosphere during transportation of bulk cargo. The developed numerical models make it possible to calculate the dust loss process, taking into account the use of the air injection of the car. They require a small cost of the computer time during practical realization at the low and medium power machines. There were submitted computational calculations to determine pollutant concentrations and the formation of the zone of pollution near the train with bulk cargo in «microscale» scale taking into account the air curtains. Originality. 2D numerical models taking into account the relevant factors influencing the process of dispersion of pollutants in the atmosphere, and the formation of the zone of pollution during transportation of bulk cargo by

  7. Dust of dark energy

    International Nuclear Information System (INIS)

    Lim, Eugene A.; Sawicki, Ignacy; Vikman, Alexander

    2010-01-01

    We introduce a novel class of field theories where energy always flows along timelike geodesics, mimicking in that respect dust, yet which possess non-zero pressure. This theory comprises two scalar fields, one of which is a Lagrange multiplier enforcing a constraint between the other's field value and derivative. We show that this system possesses no wave-like modes but retains a single dynamical degree of freedom. Thus, the sound speed is always identically zero on all backgrounds. In particular, cosmological perturbations reproduce the standard behaviour for hydrodynamics in the limit of vanishing sound speed. Using all these properties we propose a model unifying Dark Matter and Dark Energy in a single degree of freedom. In a certain limit this model exactly reproduces the evolution history of ΛCDM, while deviations away from the standard expansion history produce a potentially measurable difference in the evolution of structure

  8. Ulysses dust measurements near Jupiter.

    Science.gov (United States)

    Grün, E; Zook, H A; Baguhl, M; Fechtig, H; Hanner, M S; Kissel, J; Lindblad, B A; Linkert, D; Linkert, G; Mann, I B

    1992-09-11

    Submicrometer- to micrometer-sized particles were recorded by the Ulysses dust detector within 40 days of the Jupiter flyby. Nine impacts were recorded within 50 Jupiter radii with most of them recorded after closest approach. Three of these impacts are consistent with particles on prograde orbits around Jupiter and the rest are believed to have resulted from gravitationally focused interplanetary dust. From the ratio of the impact rate before the Jupiter flyby to the impact rate after the Jupiter flyby it is concluded that interplanetary dust particles at the distance of Jupiter move on mostly retrograde orbits. On 10 March 1992, Ulysses passed through an intense dust stream. The dust detector recorded 126 impacts within 26 hours. The stream particles were moving on highly inclined and apparently hyperbolic orbits with perihelion distances of >5 astronomical units. Interplanetary dust is lost rather quickly from the solar system through collisions and other mechanisms and must be almost continuously replenished to maintain observed abundances. Dust flux measurements, therefore, give evidence of the recent rates of production from sources such as comets, asteroids, and moons, as well as the possible presence of interstellar grains.

  9. Experiments on Dust Grain Charging

    Science.gov (United States)

    Abbas, M. N.; Craven, P. D.; Spann, J. F.; Tankosic, D.; LeClair, A.; West, E. A.

    2004-01-01

    Dust particles in various astrophysical environments are charged by a variety of mechanisms generally involving collisional processes with other charged particles and photoelectric emission with UV radiation from nearby sources. The sign and the magnitude of the particle charge are determined by the competition between the charging processes by UV radiation and collisions with charged particles. Knowledge of the particle charges and equilibrium potentials is important for understanding of a number of physical processes. The charge of a dust grain is thus a fundamental parameter that influences the physics of dusty plasmas, processes in the interplanetary medium and interstellar medium, interstellar dust clouds, planetary rings, cometary and outer atmospheres of planets etc. In this paper we present some results of experiments on charging of dust grains carried out on a laboratory facility capable levitating micron size dust grains in an electrodynamic balance in simulated space environments. The charging/discharging experiments were carried out by exposing the dust grains to energetic electron beams and UV radiation. Photoelectric efficiencies and yields of micron size dust grains of SiO2, and lunar simulates obtained from NASA-JSC will be presented.

  10. Samtidskunst og migration

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2010-01-01

    "Samtidskunst og migration. En oversigt over faglitteraturen" er en forskningsoversigt der gør status over hvad der hidtil er skrevet inden for det kunsthistoriske område om vor tids billedkunst og migration som politisk, socialt og kulturelt fænomen, primært i forbindelse med immigration til...

  11. The Great Migration.

    Science.gov (United States)

    Trotter, Joe William, Jr.

    2002-01-01

    Describes the migration of African Americans in the United States and the reasons why African Americans migrated from the south. Focuses on issues, such as the effect of World War I, the opportunities offered in the north, and the emergence of a black industrial working class. (CMK)

  12. Migrating Art History

    DEFF Research Database (Denmark)

    Ørum, Tania

    2012-01-01

    Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0.......Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0....

  13. College Student Migration.

    Science.gov (United States)

    Fenske, Robert H.; And Others

    This study examines the background characteristics of two large national samples of first-time enrolled freshmen who (a) attended college within their state of residence but away from their home community, (b) migrated to a college in an adjacent state, (c) migrated to a college in a distant state, and (d) attended college in their home community.…

  14. Migration, klima og sundhed

    DEFF Research Database (Denmark)

    Tellier, Siri; Carballo, Manuel

    2009-01-01

    Many tentative connections have been postulated between migration and climate. This article points to rural-urban migration, particularly into low elevation urban slums prone to flooding as an issue needing urgent attention by health professionals. It also notes the no-man's land in which environ...

  15. Migration in Burkina Faso

    NARCIS (Netherlands)

    Wouterse, F.S.

    2007-01-01

    Migration plays an important role in development and as a strategy for poverty reduction. A recent World Bank investigation finds a significant positive relationship between international migration and poverty reduction at the country level (Adams and Page 2003). Burkina Faso, whose conditions for

  16. Migration, Narration, Identity

    DEFF Research Database (Denmark)

    Leese, Peter

    (co-editor with Carly McLaughlin and Wladyslaw Witalisz) This book presents articles resulting from joint research on the representations of migration conducted in connection with the Erasmus Intensive Programme entitled «Migration and Narration» taught to groups of international students over...

  17. A dust-free dock

    Energy Technology Data Exchange (ETDEWEB)

    Merrion, D. [E & F Services Ltd. (United Kingdom)

    2002-10-01

    This paper describes the process of unloading coal, petcoke and other dusty products in environmentally-sensitive areas. It presents a case study of the deepwater Port of Foynes on the west coast of Ireland which imports animal feed, fertiliser, coal and cement clinker, where dockside mobile loaders (DMLs) have eliminated spillage and controlled dust, and a record case study of the Humber International Terminal in the UK, where air curtinas, dust suppression grids and EFFEX{reg_sign} filters overcome the dust problems. 2 photos.

  18. Triton's streaks as windblown dust

    Science.gov (United States)

    Sagan, Carl; Chyba, Christopher

    1990-01-01

    Explanations for the surface streaks observed by Voyager 2 on Triton's southern hemisphere are discussed. It is shown that, despite Triton's tenuous atmosphere, low-cohesion dust trains with diameters of about 5 micron or less may be carried into suspension by aeolian surface shear stress, given expected geostrophic wind speeds of about 10 m/s. For geyser-like erupting dust plumes, it is shown that dust-settling time scales and expected wind velocities can produce streaks with length scales in good agreement with those of the streaks. Thus, both geyserlike eruptions or direct lifting by surface winds appear to be viable mechanisms for the origin of the streaks.

  19. [Asthma due to grain dust].

    Science.gov (United States)

    Baur, X; Preisser, A; Wegner, R

    2003-06-01

    The actual literature as well as two case reports described in detail show that grain dust induces asthmatic reactions and ODTS which are obviously not of allergic origin. For diagnosis occupational-type exposure tests are decisive whereas allergological testing usually is not. Endotoxins which are present in the grain dust samples in high concentrations have to be regarded as the major causative components. To avoid irreversible lung function impairment a comprehensive early diagnosis is necessary. Generally, a remarkable reduction of exposure to dust with high levels of airborne endotoxin in agriculture has to be achieved since in many workplaces corresponding exposures are still rather high.

  20. Particle size traces modern Saharan dust transport and deposition across the equatorial North Atlantic

    Directory of Open Access Journals (Sweden)

    M. van der Does

    2016-11-01

    Full Text Available Mineral dust has a large impact on regional and global climate, depending on its particle size. Especially in the Atlantic Ocean downwind of the Sahara, the largest dust source on earth, the effects can be substantial but are poorly understood. This study focuses on seasonal and spatial variations in particle size of Saharan dust deposition across the Atlantic Ocean, using an array of submarine sediment traps moored along a transect at 12° N. We show that the particle size decreases downwind with increased distance from the Saharan source, due to higher gravitational settling velocities of coarse particles in the atmosphere. Modal grain sizes vary between 4 and 32 µm throughout the different seasons and at five locations along the transect. This is much coarser than previously suggested and incorporated into climate models. In addition, seasonal changes are prominent, with coarser dust in summer and finer dust in winter and spring. Such seasonal changes are caused by transport at higher altitudes and at greater wind velocities during summer than in winter. Also, the latitudinal migration of the dust cloud, associated with the Intertropical Convergence Zone, causes seasonal differences in deposition as the summer dust cloud is located more to the north and more directly above the sampled transect. Furthermore, increased precipitation and more frequent dust storms in summer coincide with coarser dust deposition. Our findings contribute to understanding Saharan dust transport and deposition relevant for the interpretation of sedimentary records for climate reconstructions, as well as for global and regional models for improved prediction of future climate.

  1. The Globalisation of migration

    Directory of Open Access Journals (Sweden)

    Milan Mesić

    2002-04-01

    Full Text Available The paper demonstrates that contemporary international migration is a constitutive part of the globalisation process. After defining the concepts of globalisation and the globalisation of migration, the author discusses six key themes, linking globalisation and international migration (“global cities”, the scale of migration; diversification of migration flows; globalisation of science and education; international migration and citizenship; emigrant communities and new identities. First, in accordance with Saskia Sassen’s analysis, the author rejects the wide-spread notion that unqualified migrants have lost an (important role in »global cities«, i.e. in the centres of the new (global economy. Namely, the post-modern service sector cannot function without the support of a wide range of auxiliary unqualified workers. Second, a critical comparison with traditional overseas mass migration to the USA at the turn of the 19th and 20th centuries indicates that present international migration is, perhaps, less extensive – however it is important to take into consideration various limitations that previously did not exist, and thus the present migration potential is in really greater. Third, globalisation is more evident in a diversification of the forms of migration: the source area of migrants to the New World and Europe has expanded to include new regions in the world; new immigration areas have arisen (the Middle East, new industrial countries of the Far East, South Europe; intra-regional migration has intensified. Forth, globalisation is linked to an increased migration of experts and the pessimistic notion of a brain drain has been replaced by the optimistic idea of a brain gain. Fifth, contemporary international migration has been associated with a crisis of the national model of citizenship. Sixth, the interlinking of (migrant cultural communities regardless of distance and the physical proximity of cultural centres (the

  2. Malaysia and forced migration

    Directory of Open Access Journals (Sweden)

    Arzura Idris

    2012-06-01

    Full Text Available This paper analyzes the phenomenon of “forced migration” in Malaysia. It examines the nature of forced migration, the challenges faced by Malaysia, the policy responses and their impact on the country and upon the forced migrants. It considers forced migration as an event hosting multifaceted issues related and relevant to forced migrants and suggests that Malaysia has been preoccupied with the issue of forced migration movements. This is largely seen in various responses invoked from Malaysia due to “south-south forced migration movements.” These responses are, however, inadequate in terms of commitment to the international refugee regime. While Malaysia did respond to economic and migration challenges, the paper asserts that such efforts are futile if she ignores issues critical to forced migrants.

  3. Dust Dynamics Near Planetary Surfaces

    Science.gov (United States)

    Colwell, Joshua; Hughes, Anna; Grund, Chris

    Observations of a lunar "horizon glow" by several Surveyor spacecraft in the 1960s opened the study of the dynamics of charged dust particles near planetary surfaces. The surfaces of the Moon and other airless planetary bodies in the solar system (asteroids, and other moons) are directly exposed to the solar wind and ionizing solar ultraviolet radiation, resulting in a time-dependent electric surface potential. Because these same objects are also exposed to bombardment by micrometeoroids, the surfaces are usually characterized by a power-law size distribution of dust that extends to sub-micron-sized particles. Individual particles can acquire a charge different from their surroundings leading to electrostatic levitation. Once levitated, particles may simply return to the surface on nearly ballistic trajectories, escape entirely from the moon or asteroid if the initial velocity is large, or in some cases be stably levitated for extended periods of time. All three outcomes have observable consequences. Furthermore, the behavior of charged dust near the surface has practical implications for planned future manned and unmanned activities on the lunar surface. Charged dust particles also act as sensitive probes of the near-surface plasma environment. Recent numerical modeling of dust levitation and transport show that charged micron-sized dust is likely to accumulate in topographic lows such as craters, providing a mechanism for the creation of dust "ponds" observed on the asteroid 433 Eros. Such deposition can occur when particles are supported by the photoelectron sheath above the dayside and drift over shadowed regions of craters where the surface potential is much smaller. Earlier studies of the lunar horizon glow are consistent with those particles being on simple ballistic trajectories following electrostatic launching from the surface. Smaller particles may be accelerated from the lunar surface to high altitudes consistent with observations of high altitude

  4. Bounded dust-acoustic waves in a cylindrically bounded collisional dusty plasma with dust charge variation

    International Nuclear Information System (INIS)

    Wei Nanxia; Xue Jukui

    2006-01-01

    Taking into account the boundary, particle collisions, and dust charging effects, dust-acoustic waves in a uniform cylindrically bounded dusty plasma is investigated analytically, and the dispersion relation for the dust-acoustic wave is obtained. The effects of boundary, dust charge variation, particle collision, and dust size on the dust-acoustic wave are discussed in detail. Due to the bounded cylindrical boundary effects, the radial wave number is discrete, i.e., the spectrum is discrete. It is shown that the discrete spectrum, the adiabatic dust charge variation, dust grain size, and the particle collision have significant effects on the dust-acoustic wave

  5. Dependence of secondary electron emission on the incident angle and the energy of primary electrons bombarding bowl-structured beryllium surfaces

    International Nuclear Information System (INIS)

    Kawata, Jun; Ohya, Kaoru.

    1994-01-01

    A Monte Carlo simulation of the secondary electron emission from beryllium is combined with a model of bowl structure for surface roughness, for analyzing the difference between the electron emissions for normal and oblique incidences. At normal incidence, with increasing the roughness parameter H/W, the primary energy E pm at which the maximum electron yield occurs becomes higher, and at more than the E pm , the decrease in the yield is slower; where H and W are the depth and width of the bowl structure, respectively. The dispersion of incident angle to the microscopic surface causes a small increase in the yield at oblique incidence, whereas the blocking of primary electrons from bombarding the bottom of the structure causes an opposite trend. The strong anisotropy in the polar angular distribution with respect to the azimuthal angle is calculated at oblique incidence. (author)

  6. Dust particle formation in silane plasmas

    NARCIS (Netherlands)

    Sorokin, M.

    2005-01-01

    Dust can be found anywhere: in the kitchen, in the car, in space… Not surprisingly we also see dust in commercial and laboratory plasmas. Dust can be introduced in the plasma, but it can also grow there by itself. In the microelectronics industry, contamination of the processing plasma by dust is an

  7. PERSPECTIVE: Dust, fertilization and sources

    Science.gov (United States)

    Remer, Lorraine A.

    2006-11-01

    Aerosols, tiny suspended particles in the atmosphere, play an important role in modifying the Earth's energy balance and are essential for the formation of cloud droplets. Suspended dust particles lifted from the world's arid regions by strong winds contain essential minerals that can be transported great distances and deposited into the ocean or on other continents where productivity is limited by lack of usable minerals [1]. Dust can transport pathogens as well as minerals great distance, contributing to the spread of human and agricultural diseases, and a portion of dust can be attributed to human activity suggesting that dust radiative effects should be included in estimates of anthropogenic climate forcing. The greenish and brownish tints in figure 1 show the wide extent of monthly mean mineral dust transport, as viewed by the MODerate resolution Imaging Spectroradiometer (MODIS) satellite sensor. The monthly mean global aerosol system for February 2006 from the MODIS aboard the Terra satellite Figure 1. The monthly mean global aerosol system for February 2006 from the MODIS aboard the Terra satellite. The brighter the color, the greater the aerosol loading. Red and reddish tints indicate aerosol dominated by small particles created primarily from combustion processes. Green and brownish tints indicate larger particles created from wind-driven processes, usually transported desert dust. Note the bright green band at the southern edge of the Saharan desert, the reddish band it must cross if transported to the southwest and the long brownish transport path as it crosses the Atlantic to South America. Image courtesy of the NASA Earth Observatory (http://earthobservatory.nasa.gov). Even though qualitatively we recognize the extent and importance of dust transport and the role that it plays in fertilizing nutrient-limited regions, there is much that is still unknown. We are just now beginning to quantify the amount of dust that exits one continental region and the

  8. Loess and Eolian Dust Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past environment derived from Loess and Eolian dust (silt-sized material deposited on the Earth surface by the surface winds. Parameter keywords describe...

  9. 75 FR 3881 - Combustible Dust

    Science.gov (United States)

    2010-01-25

    ..., rubber, drugs, dried blood, dyes, certain textiles, and metals (such as aluminum and magnesium..., furniture manufacturing, metal processing, fabricated metal products and machinery manufacturing, pesticide... standard that will comprehensively address the fire and explosion hazards of combustible dust. The Agency...

  10. Rethinking wood dust safety standards

    OpenAIRE

    Ratnasingam, Jega; Wai, Lim Tau; Ramasamy, Geetha; Ioras, Florin; Tadin, Ishak; Universiti Putra Malaysia; Buckinghamshire New University; Centre for Occupational Safety and Health Singapore

    2015-01-01

    The current universal work safety and health standards pertaining to wood dust in factories lack the localisation required. As a study has shown, there is a urgent need to reevaluate the current guidelines and practices.

  11. Deciphering the Role of Desert Dust in the Climate Puzzle: The Mediterranean Israeli Dust Experiment (MEIDEX)

    Science.gov (United States)

    Levin, Zev; Joseph, Joachim; Mekler, Yuri; Israelevich, Peter; Ganor, Eli; Hilsenrath, Ernest; Janz, Scott

    2002-01-01

    Numerous studies have shown that aerosol particles may be one of the primary agents that can offset the climate warming induced by the increase in the amount of atmospheric greenhouse gases. Desert aerosols are probably the most abundant and massive type of aerosol particles that are present in the atmosphere worldwide. These aerosols are carried over large distances and have various global impacts. They interact with clouds, impact the efficiency of their rain production and change their optical properties. They constitute one of the primary sources of minerals for oceanic life and influence the health of coral reefs. They have direct effects on human health, especially by inducing breathing difficulties in children. It was lately discovered that desert particles carry pathogens from the Sahara desert over the Atlantic Ocean, a fact that may explain the migration of certain types of diseases. Aerosols not only absorb solar radiation but also scatter it, so that their climatic effect is influenced not only by their physical properties and height distribution but also by the reflectivity of the underlying surface. This latter property changes greatly over land and is low over ocean surfaces. Aerosol plumes are emitted from discrete, sporadic sources in the desert areas of the world and are transported worldwide by the atmosphere's wind systems. For example, Saharan dust reaches Mexico City, Florida, Ireland, Switzerland and the Mediterranean region, while Asian dust reaches Alaska, Hawaii and the continental United States. This means that in order to assess its global effects, one must observe dust from space. The Space Shuttle is a unique platform, because it flies over the major deserts of our planet, enabling measurements and remote sensing of the aerosols as they travel from source to sink regions. Such efforts must always be accompanied by in-situ data for validation and calibration, with direct sampling of the airborne particles. MEIDEX is a joint project of

  12. Physical properties of five grain dust types.

    OpenAIRE

    Parnell, C B; Jones, D D; Rutherford, R D; Goforth, K J

    1986-01-01

    Physical properties of grain dust derived from five grain types (soybean, rice, corn, wheat, and sorghum) were measured and reported. The grain dusts were obtained from dust collection systems of terminal grain handling facilities and were assumed to be representative of grain dust generated during the handling process. The physical properties reported were as follows: particle size distributions and surface area measurements using a Coulter Counter Model TAII; percent dust fractions less tha...

  13. Efficient radiative transfer in dust grain mixtures

    OpenAIRE

    Wolf, S.

    2002-01-01

    The influence of a dust grain mixture consisting of spherical dust grains with different radii and/or chemical composition on the resulting temperature structure and spectral energy distribution of a circumstellar shell is investigated. The comparison with the results based on an approximation of dust grain parameters representing the mean optical properties of the corresponding dust grain mixture reveal that (1) the temperature dispersion of a real dust grain mixture decreases substantially ...

  14. Migration and AIDS.

    Science.gov (United States)

    1998-01-01

    This article presents the perspectives of UNAIDS and the International Organization for Migration (IOM) on migration and HIV/AIDS. It identifies research and action priorities and policy issues, and describes the current situation in major regions of the world. Migration is a process. Movement is enhanced by air transport, rising international trade, deregulation of trade practices, and opening of borders. Movements are restricted by laws and statutes. Denial to freely circulate and obtain asylum is associated with vulnerability to HIV infections. A UNAIDS policy paper in 1997 and IOM policy guidelines in 1988 affirm that refugees and asylum seekers should not be targeted for special measures due to HIV/AIDS. There is an urgent need to provide primary health services for migrants, voluntary counseling and testing, and more favorable conditions. Research is needed on the role of migration in the spread of HIV, the extent of migration, availability of health services, and options for HIV prevention. Research must be action-oriented and focused on vulnerability to HIV and risk taking behavior. There is substantial mobility in West and Central Africa, economic migration in South Africa, and nonvoluntary migration in Angola. Sex workers in southeast Asia contribute to the spread. The breakup of the USSR led to population shifts. Migrants in Central America and Mexico move north to the US where HIV prevalence is higher.

  15. Facile Synthesis of Bowl-Like LiFePO4/C Composite with High Rate-Performance

    Science.gov (United States)

    Jing, Peng; Yao, Lei; Xiang, Mingwu; Wang, Yan; Wu, Jinhua; Wang, Boya; Zhang, Yun; Wu, Hao; Liu, Heng

    2018-03-01

    Olivine-structured LiFePO4/C composites with high rate-performance were synthesized via an industrial spray-drying technique using a low cost Fe3O4 as iron source. The as-obtained LiFePO4/C exhibits a unique bowl-like morphology with a particle size of 2-5 μm in diameter. A continuous uniform carbon coating layer on the surface of LiFePO4/C cathodes promotes fast electron transport, whilst it guarantees the favorable electrochemical reaction. Especially the formation of porous structure leads to an average pore volume of 0.127 cm3 g-1 and a high specific surface area of 34.46 m2 g-1, which is conducive to facilitating the penetration of electrolyte and providing the more contact area of electrolyte with LiFePO4/C. As a result, the as-prepared LiFePO4/C cathode material delivers an outstanding discharge capacity of 102.1 mAh g-1, 94.2% of the initial capacity (108.3 mAh g-1), after 1000 cycles at 10 C. Even at an ultrahigh current rate of 50 C, it still shows an initial discharge capacity of 58 mAh g-1.

  16. Facile Synthesis of Bowl-Like LiFePO4/C Composite with High Rate-Performance

    Science.gov (United States)

    Jing, Peng; Yao, Lei; Xiang, Mingwu; Wang, Yan; Wu, Jinhua; Wang, Boya; Zhang, Yun; Wu, Hao; Liu, Heng

    2018-07-01

    Olivine-structured LiFePO4/C composites with high rate-performance were synthesized via an industrial spray-drying technique using a low cost Fe3O4 as iron source. The as-obtained LiFePO4/C exhibits a unique bowl-like morphology with a particle size of 2-5 μm in diameter. A continuous uniform carbon coating layer on the surface of LiFePO4/C cathodes promotes fast electron transport, whilst it guarantees the favorable electrochemical reaction. Especially the formation of porous structure leads to an average pore volume of 0.127 cm3 g-1 and a high specific surface area of 34.46 m2 g-1, which is conducive to facilitating the penetration of electrolyte and providing the more contact area of electrolyte with LiFePO4/C. As a result, the as-prepared LiFePO4/C cathode material delivers an outstanding discharge capacity of 102.1 mAh g-1, 94.2% of the initial capacity (108.3 mAh g-1), after 1000 cycles at 10 C. Even at an ultrahigh current rate of 50 C, it still shows an initial discharge capacity of 58 mAh g-1.

  17. Grain dust and the lungs.

    Science.gov (United States)

    Chan-Yeung, M.; Ashley, M. J.; Grzybowski, S.

    1978-01-01

    Grain dust is composed of a large number of materials, including various types of grain and their disintegration products, silica, fungi, insects and mites. The clinical syndromes described in relation to exposure to grain dust are chronic bronchitis, grain dust asthma, extrinsic allergic alveolitis, grain fever and silo-filler's lung. Rhinitis and conjunctivitis are also common in grain workers. While the concentration and the quality of dust influence the frequency and the type of clinical syndrome in grain workers, host factors are also important. Of the latter, smoking is the most important factor influencing the frequency of chronic bronchitis. The role of atopy and of bronchial hyperreactivity in grain dust asthma has yet to be assessed. Several well designed studies are currently being carried out in North America not only to delineate the frequency of the respiratory abnormalities, the pathogenetic mechanisms and the host factors, but also to establish a meaningful threshold limit concentration for grain dust. Images p1272-a PMID:348288

  18. Charged dust structures in plasmas

    International Nuclear Information System (INIS)

    Cramer, N.F.; Vladimirov, S.V.

    1999-01-01

    We report here on theoretical investigations of the mechanical-electrostatic modes of vibration of a dust-plasma crystal, extending earlier work on the transverse modes of a horizontal line of grains (where the ions flow vertically downward to a plane horizontal cathode), the modes of two such lines of grains, and the modes of a vertical string of grains. The last two arrangements have the unique feature that the effect of the background plasma on the mutual grain interaction is asymmetric because of the wake downstream of the grains studied in. The characteristic frequencies of the vibrations are dependent on the parameters of the plasma and the dust grains, such as the Debye length and the grain charge, and so measurement of the frequencies could provide diagnostics of these quantities. Although the current boom in dusty plasma research is driven mainly by such industrial applications as plasma etching, sputtering and deposition, the physical outcomes of investigations in this rapidly expanding field cover many important topics in space physics and astrophysics as well. Examples are the interaction of dust with spacecraft, the structure of planetary rings, star formation, supernova explosions and shock waves. In addition, the study of the influence of dust in environmental research, such as in the Earth's ionosphere and atmosphere, is important. The unique binding of dust particles in a plasma opens possibilities for so-called super-chemistry, where the interacting bound elements are not atoms but dust grains

  19. Suspended dust in Norwegian cities

    International Nuclear Information System (INIS)

    2001-01-01

    According to calculations, at least 80 000 people in Oslo and 8 000 in Trondheim were annoyed by too much suspended dust in 2000. The dust concentration is greatest in the spring, presumably because dust is swirling up from melting snow and ice on the streets. Car traffic is the main source of the dust, except for some of the most highly exposed regions where wood-firing from old stoves contributes up to 70 percent of the dust. National targets for air quality include suspended dust, nitrogen dioxide, sulphur dioxide and benzene. Calculations show that nitrogen dioxide emissions exceeding the limit affected 4 000 people in Oslo and 1 000 people in Trondheim. The sulphur dioxide emissions in the major cities did non exceed the national quality limit; they did exceed the limit in some of the smaller industrial centres. In Trondheim, measurements show that the national limit for benzene was exceeded. Most of the emission of nitrogen dioxide comes from the road traffic. Local air pollution at times causes considerable health- and well-being problems in the larger cities and industrial centres, where a great part of the population may be at risk of early death, infection of the respiratory passage, heart- and lung diseases and cancer

  20. Labor migration in Asia.

    Science.gov (United States)

    Martin, P L

    1991-01-01

    "A recent conference sponsored by the United Nations Center for Regional Development (UNCRD) in Nagoya, Japan examined the growing importance of labor migration for four major Asian labor importers (Japan, Hong Kong, Malaysia, and Singapore) and five major labor exporters (Bangladesh, Korea, Pakistan, Philippines, and Thailand).... The conference concluded that international labor migration would increase within Asia because the tight labor markets and rising wages which have stimulated Japanese investment in other Asian nations, for example, have not been sufficient to eliminate migration push and pull forces...." excerpt

  1. Modification of piston bowl geometry and injection strategy, and investigation of EGR composition for a DME-burning direct injection engine

    Directory of Open Access Journals (Sweden)

    Kianoosh Shojae

    2017-01-01

    Full Text Available The amount of pollutant gases in the atmosphere has reached a critical state due to an increase in industrial development and the rapid growth of automobile industries that use fossil fuels. The combustion of fossil fuels produces harmful gases such as carbon dioxide, nitrogen monoxide (NO, soot, particulate matter (PM, etc. The use of Dimethyl Ether (DME biofuel in diesel engines or other combustion processes have been highly regarded by researchers. Studies show that the use of pure DME in automotive engines will be possible in the near future. The present work evaluated the environmental and performance effects of changing the injection strategy (time and temperature, piston bowl geometry, and exhaust gas recirculation (EGR composition for a DME-burning engine. The modification of piston bowl parameters and engine simulation were numerically performed by using AVL fire CFD code. For model validation, the calculated mean pressure and rate of heat released (RHR were compared to the experimental data and the results showed a good agreement (under a 70% load and 1200-rpm engine speed. It was found that retarding injection timing (reduction in in-cylinder temperature, consequently caused a reduction in NO emissions and increased soot formation, reciprocally; this occurred because of a reduction in temperature and a lower soot oxidation in the combustion chamber. It became clear that 3 deg before top dead center (BTDC was the appropriate injection timing for the DME-burning heavy duty diesel engine running under 1200 rpm. Also, the parametrical modification of the piston bowl geometry and the simultaneous decrease of Tm (piston bowl depth and R3 (bowl inner radius lengths were associated with lower exhaust NO emissions. For the perfect utilization of DME fuel in an HD diesel engine, the suggested proper lengths of Tm and R3 were 0.008 and 0.0079 m, respectively. Furthermore, various EGR compositions for the reduction of exhaust NO were investigated

  2. Neuronal Migration Disorders

    Science.gov (United States)

    ... Understanding Sleep The Life and Death of a Neuron Genes At Work In The Brain Order Publications ... birth defects caused by the abnormal migration of neurons in the developing brain and nervous system. In ...

  3. Migration og etnicitet

    DEFF Research Database (Denmark)

    Christiansen, Connie Carøe

    2004-01-01

    Migration og etnicitet er aktuelle og forbundne fænomener, idet migration øger berøringsfladerne mellem befolkningsgrupper. Etniciteter formes i takt med at grænser drages imellem disse grupper. Imod moderniserings-teoriernes forventning forsvandt etnicitet ikke som en traditionel eller oprindelig...... måde at skabe tilhørsforhold på; globalt set fremstår vor tid istedet som en "migrationens tidsalder", der tilsyneladende også er en tidsalder, hvor kulturelle særtræk, i form af etnicitet, udgør vigtige linjer, hvorefter grupper skilller sig ud fra hinanden. Både migration og etnicitet bringer fokus...... den finder sted i modtagerlandet, men nyere perspektiver på migration, som begreber om medborgerskab, transnationalisme og diaspora er eksponenter for, søger udover den nationalstatslige ramme og inddrager konsekvenserne af migrationen for afsenderlande....

  4. Indonesia's migration transition.

    Science.gov (United States)

    Hugo, G

    1995-01-01

    This article describes population movements in Indonesia in the context of rapid and marked social and economic change. Foreign investment in Indonesia is increasing, and global mass media is available to many households. Agriculture is being commercialized, and structural shifts are occurring in the economy. Educational levels are increasing, and women's role and status are shifting. Population migration has increased over the decades, both short and long distance, permanent and temporary, legal and illegal, and migration to and between urban areas. This article focuses specifically on rural-to-urban migration and international migration. Population settlements are dense in the agriculturally rich inner areas of Java, Bali, and Madura. Although the rate of growth of the gross domestic product was 6.8% annually during 1969-94, the World Bank ranked Indonesia as a low-income economy in 1992 because of the large population size. Income per capita is US $670. Indonesia is becoming a large exporter of labor to the Middle East, particularly women. The predominance of women as overseas contract workers is changing women's role and status in the family and is controversial due to the cases of mistreatment. Malaysia's high economic growth rate of over 8% per year means an additional 1.3 million foreign workers and technicians are needed. During the 1980s urban growth increased at a very rapid rate. Urban growth tended to occur along corridors and major transportation routes around urban areas. It is posited that most of the urban growth is due to rural-to-urban migration. Data limitations prevent an exact determination of the extent of rural-to-urban migration. More women are estimated to be involved in movements to cities during the 1980s compared to the 1970s. Recruiters and middlemen have played an important role in rural-to-urban migration and international migration.

  5. Repeat migration and disappointment.

    Science.gov (United States)

    Grant, E K; Vanderkamp, J

    1986-01-01

    This article investigates the determinants of repeat migration among the 44 regions of Canada, using information from a large micro-database which spans the period 1968 to 1971. The explanation of repeat migration probabilities is a difficult task, and this attempt is only partly successful. May of the explanatory variables are not significant, and the overall explanatory power of the equations is not high. In the area of personal characteristics, the variables related to age, sex, and marital status are generally significant and with expected signs. The distance variable has a strongly positive effect on onward move probabilities. Variables related to prior migration experience have an important impact that differs between return and onward probabilities. In particular, the occurrence of prior moves has a striking effect on the probability of onward migration. The variable representing disappointment, or relative success of the initial move, plays a significant role in explaining repeat migration probabilities. The disappointment variable represents the ratio of actural versus expected wage income in the year after the initial move, and its effect on both repeat migration probabilities is always negative and almost always highly significant. The repeat probabilities diminish after a year's stay in the destination region, but disappointment in the most recent year still has a bearing on the delayed repeat probabilities. While the quantitative impact of the disappointment variable is not large, it is difficult to draw comparisons since similar estimates are not available elsewhere.

  6. Study on treatment of dust by dismantling

    International Nuclear Information System (INIS)

    Torikai, K.; Suzuki, K.

    1987-01-01

    In dismantling of nuclear reactors, various kinds of treatment of dust generated by cutting or dismantling concrete structures of components of reactors are evaluated for safety, cost, and performance comparing the work in air with water. A method of dust treatment for work in air is discussed. The dry method has an easy operation in practice and a good performance in the equipment, but has problem on the prevention from radioactive contamination by diffusion of dust in air. For the purpose of advancing the strong points and eliminating the weak points in dry method, an improved venturi scrubber system is proposed for dismantling work as a dust collecting system. The system consists of dust absorbing pipe, dust collector, separator of dust and water and dust transfer equipment to a storage of waste. This system would be expected to have better performance and lower operating cost in decommissioning nuclear reactors, especially, the number of dust filters, for example, HEPA filters, will be considerably saved

  7. Development of DUST: A computer code that calculates release rates from a LLW disposal unit

    International Nuclear Information System (INIS)

    Sullivan, T.M.

    1992-01-01

    Performance assessment of a Low-Level Waste (LLW) disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the disposal unit source term). The major physical processes that influence the source term are water flow, container degradation, waste form leaching, and radionuclide transport. A computer code, DUST (Disposal Unit Source Term) has been developed which incorporates these processes in a unified manner. The DUST code improves upon existing codes as it has the capability to model multiple container failure times, multiple waste form release properties, and radionuclide specific transport properties. Verification studies performed on the code are discussed

  8. Four Interstellar Dust Candidates from the Stardust Interstellar Dust Collector

    Science.gov (United States)

    Westphal, A. J.; Allen, C.; Bajt, S.; Bechtel, H. A.; Borg, J.; Brenker, F.; Bridges, J.; Brownlee, D. E.; Burchell, M.; Burghammer, M.; hide

    2011-01-01

    In January 2006, the Stardust sample return capsule returned to Earth bearing the first solid samples from a primitive solar system body, Comet 81P/Wild2, and a collector dedicated to the capture and return of contemporary interstellar dust. Both collectors were approx. 0.1 sq m in area and were composed of aerogel tiles (85% of the collecting area) and aluminum foils. The Stardust Interstellar Dust Collector (SIDC) was exposed to the interstellar dust stream for a total exposure factor of 20 sq m/day. The Stardust Interstellar Preliminary Examination (ISPE) is a consortium-based project to characterize the collection using nondestructive techniques. The goals and restrictions of the ISPE are described . A summary of analytical techniques is described.

  9. Cosmic dust investigations. Pt. 2

    International Nuclear Information System (INIS)

    Simpson, J.A.; Tuzzolino, A.J.

    1989-01-01

    A series of experiments have been completed using accelerator dust particles in the mass range ≅ 10 -9 -10 -6 g and velocity range ≅ 2-12 km/s to measure the velocity loss and degree of fragmentation for dust particles penetrating 6 and 28 μm thick polyvinylidene fluoride (PVDF) dust detectors. These measurements prove that even for a ratio of PVDF foil thickness to particle diameter as large as 0.6, the velocity loss and fragmentation is far less than expected from earlier reports in the literature. For 6 μm thick foils the velocity loss is ≤5%. These experiments are based on an extension of our earlier work which showed that two PVDF foils spaced a given distance apart could provide accurate time-of-flight (TOF) information due to the fast pulse rise time of PVDF detector response. We also report on our present state of development of PVDF position-sensing detectors which identify the x, y coordinates of particle impact, using detector and electronic pulse techniques adapted from our semiconductor position-sensing cosmic-ray detectors. Typical position errors of ≅ 1 mm are readily achieved. Finally, we have combined the above developments into a dust-particle telescope which accurately (≅ 1 0 angular accuracy) measures the trajectory of the incident particle as well as its mass and incident velocity, irrespective of whether it is a charged or neutral particle. We discuss how this practical dust telescope can be combined with dust capture cells for space flight and later recovery for laboratory determination of elemental and isotopic composition of captured dust. We also describe a simpler trajectory array based on discrete mosaics of thin detectors which would measure trajectories with a mean angular error of ≅ 4 0 . We discuss the application of these instruments for distinguishing between interplanetary dust of cometary and asteroidal origin, and for measurements on a space station, from near-Earth trapped dust of artificial origin. (orig.)

  10. Charged dust in saturn's magnetosphere

    International Nuclear Information System (INIS)

    Mendis, D.A.; Hill, J.R.; Houpis, H.L.F.

    1983-01-01

    Gravito-electrodynamic theory of charged dust grains is used to explain a variety of phenomena in those portions of the Saturnian ring system that are known to be dominated by fine (micron- and submicron-sized) dust, and in which collisional forces and Coulomb drag can be neglected. Among the phenomena discussed are the formation and evolution of the rotating near-radial spokes in the B-ring, the formation of waves in the F-ring, the cause of eccentricities of certain isolated ringlets, and the origin and morphology of the broad diffuse E-ring. Several novel processes predicted by the gravitoelectrodynamic theory, including 'magneto-gravitational capture' of exogenic dust by the magnetosphere, '1:1 magneto-gravitational orbital resonances' of charged dust with nearby satellites, and 'gyro-orbital resonances,' are used to explain individual observations. The effect of a ring current associated with this charged dust is also evaluated. Finally, the cosmogonic implications of the magneto-gravitational theory are briefly discussed. While several (although not all) of these processes have been discussed by one or more of the present authors elsewhere, the purpose of this paper is to synthesize all these processes within the framework of gravito-electrodynamics, and also to show its range of applicability within Saturn's ring system

  11. Spring Dust Storm Smothers Beijing

    Science.gov (United States)

    2002-01-01

    A few days earlier than usual, a large, dense plume of dust blew southward and eastward from the desert plains of Mongolia-quite smothering to the residents of Beijing. Citizens of northeastern China call this annual event the 'shachenbao,' or 'dust cloud tempest.' However, the tempest normally occurs during the spring time. The dust storm hit Beijing on Friday night, March 15, and began coating everything with a fine, pale brown layer of grit. The region is quite dry; a problem some believe has been exacerbated by decades of deforestation. According to Chinese government estimates, roughly 1 million tons of desert dust and sand blow into Beijing each year. This true-color image was made using two adjacent swaths (click to see the full image) of data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), flying aboard the OrbView-2 satellite, on March 17, 2002. The massive dust storm (brownish pixels) can easily be distinguished from clouds (bright white pixels) as it blows across northern Japan and eastward toward the open Pacific Ocean. The black regions are gaps between SeaWiFS' viewing swaths and represent areas where no data were collected. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  12. Physical properties of five grain dust types.

    Science.gov (United States)

    Parnell, C B; Jones, D D; Rutherford, R D; Goforth, K J

    1986-01-01

    Physical properties of grain dust derived from five grain types (soybean, rice, corn, wheat, and sorghum) were measured and reported. The grain dusts were obtained from dust collection systems of terminal grain handling facilities and were assumed to be representative of grain dust generated during the handling process. The physical properties reported were as follows: particle size distributions and surface area measurements using a Coulter Counter Model TAII; percent dust fractions less than 100 micron of whole dust; bulk density; particle density; and ash content. PMID:3709482

  13. Managing migration: the Brazilian case

    OpenAIRE

    Eduardo L. G. Rios-Neto

    2005-01-01

    The objective of this paper is to present the Brazilian migration experience and its relationship with migration management. The article is divided into three parts. First, it reviews some basic facts regarding Brazilian immigration and emigration processes. Second, it focuses on some policy and legal issues related to migration. Finally, it addresses five issues regarding migration management in Brazil.

  14. Determination of residual volatile organic compounds migrated from polystyrene food packaging into food simulant by headspace solid phase micro extraction-gas chromatography

    International Nuclear Information System (INIS)

    Mohd Marsin Sanagi; Ling, Susie Lu; Zalilah Nasir; Wan Aini Wan Ibrahim; Abu Naim, Ahmedy

    2008-01-01

    The residual styrene and other volatile organic compounds (VOCs) present in the polystyrene food packaging are of concern as these compounds have the potential to migrate into the food in contact. This work describes a method for quantitative determination of VOCs, namely styrene, toluene, ethyl benzene, iso-propylbenzene and n-propylbenzene that have migrated from polystyrene food packaging into food stimulant by gas chromatography-flame ionization detection (GC-FID). Headspace solid phase micro extraction (HS-SPME) technique was applied for migration test using water as food stimulant. The effects of extraction variables including sample volume, eluotropic strength, extraction temperature, extraction time, desorption time, sample agitation, and salt addition on the amounts of the extracted analyses were studied to obtain the optimal HS-SPME conditions. The optimized method was applied to test the VOCs migrated from polystyrene bowls and cups at storage temperatures ranging from 24 to 80 degree Celsius for 30 min. Styrene and ethyl benzene were found to migrate from the samples into the food stimulant. The migration of analyze was found to be strongly dependent upon the storage temperature. The HS-SPME is useful as an alternative method to determine the migration of VOCs from food packaging material into food stimulant. (author)

  15. Glass Frit Clumping And Dusting

    International Nuclear Information System (INIS)

    Steimke, J. L.

    2013-01-01

    DWPF mixes a slurry of glass frit (Frit 418) and dilute (1.5 wt%) formic acid solution with high level waste in the Slurry Mix Evaporator (SME). There would be advantages to introducing the frit in a non-slurry form to minimize water addition to the SME, however, adding completely dry frit has the potential to generate dust which could clog filters or condensers. Prior testing with another type of frit, Frit 320, and using a minimal amount of water reduced dust generation, however, the formation of hard clumps was observed. To examine options and behavior, a TTQAP [McCabe and Stone, 2013] was written to initiate tests that would address these concerns. Tests were conducted with four types of glass frit; Frit 320, DWPF Frit 418, Bekeson Frit 418 and Multi-Aspirator Frit 418. The last two frits are chemically identical to DWPF Frit 418 but smaller particles were removed by the respective vendors. Test results on Frit Clumping and Dusting are provided in this report. This report addresses the following seven questions. Short answers are provided below with more detailed answers to follow. 1. Will the addition of a small amount of water, 1.5 wt%, to dry DWPF Frit 418 greatly reduce the dust generation during handling at DWPF? a. Yes, a small scale test showed that adding a little water to the frit greatly reduced dust generation during handling. 2. Will the addition of small amounts of water to the frit cause clumping that will impair frit handling at DWPF? a. No, not with Frit 418. Although clumps were observed to form when 1.5 wt% water was mixed with DWPF Frit 418, then compressed and air-dried overnight, the clumps were easily crushed and did not form the hardened material noted when Frit 320 was tested. 3. What is the measured size distribution of dust generated when dry frit is handled? (This affects the feasibility and choice of processing equipment for removing the dust generating fraction of the frit before it is added to the SME.) a. The size distribution for

  16. Glass Frit Clumping And Dusting

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J. L.

    2013-09-26

    DWPF mixes a slurry of glass frit (Frit 418) and dilute (1.5 wt%) formic acid solution with high level waste in the Slurry Mix Evaporator (SME). There would be advantages to introducing the frit in a non-slurry form to minimize water addition to the SME, however, adding completely dry frit has the potential to generate dust which could clog filters or condensers. Prior testing with another type of frit, Frit 320, and using a minimal amount of water reduced dust generation, however, the formation of hard clumps was observed. To examine options and behavior, a TTQAP [McCabe and Stone, 2013] was written to initiate tests that would address these concerns. Tests were conducted with four types of glass frit; Frit 320, DWPF Frit 418, Bekeson Frit 418 and Multi-Aspirator Frit 418. The last two frits are chemically identical to DWPF Frit 418 but smaller particles were removed by the respective vendors. Test results on Frit Clumping and Dusting are provided in this report. This report addresses the following seven questions. Short answers are provided below with more detailed answers to follow. 1. Will the addition of a small amount of water, 1.5 wt%, to dry DWPF Frit 418 greatly reduce the dust generation during handling at DWPF? a. Yes, a small scale test showed that adding a little water to the frit greatly reduced dust generation during handling. 2. Will the addition of small amounts of water to the frit cause clumping that will impair frit handling at DWPF? a. No, not with Frit 418. Although clumps were observed to form when 1.5 wt% water was mixed with DWPF Frit 418, then compressed and air-dried overnight, the clumps were easily crushed and did not form the hardened material noted when Frit 320 was tested. 3. What is the measured size distribution of dust generated when dry frit is handled? (This affects the feasibility and choice of processing equipment for removing the dust generating fraction of the frit before it is added to the SME.) a. The size distribution for

  17. Dust deposit in recirculation regions

    International Nuclear Information System (INIS)

    Griemert, R.

    1985-03-01

    The present report shows investigations, which have been carried out in a closed duct at forward and backward facing steps. Distribution of fluid velocity and fluid fluctuations in and normal to main flow direction as well as the distribution of Reynolds shear stress have been measured. The mass transfer downstream of a backward facing step has been investigated as well. By using graphite-, copper-, tin- and rubber dust, conditions of deposition have been defined experimentally. A serie of photos shows the filling of a recirculation region downstream of a backward facing step with graphite dust. The present investigations allow to avoid deposition of dust in recirculation regions by selecting the fluid numbers in an appropriate way. (orig.) [de

  18. Dust Storm Hits Canary Islands

    Science.gov (United States)

    2002-01-01

    A thick pall of sand and dust blew out from the Sahara Desert over the Atlantic Ocean yesterday (January 6, 2002), engulfing the Canary Islands in what has become one of the worst sand storms ever recorded there. In this scene, notice how the dust appears particularly thick in the downwind wake of Tenerife, the largest of the Canary Islands. Perhaps the turbulence generated by the air currents flowing past the island's volcanic peaks is churning the dust back up into the atmosphere, rather than allowing it to settle toward the surface. This true-color image was captured by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite, on January 7, 2002. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  19. Mechanisms of metal dusting corrosion

    DEFF Research Database (Denmark)

    Hummelshøj, Thomas Strabo

    In this thesis the early stages of metal dusting corrosion is addressed; the development of carbon expanded austenite, C, and the decomposition hereof into carbides. Later stages of metal dusting corrosion are explored by a systematic study of stainless steel foils exposed to metal dusting...... deformed stainless steel flakes is transformed to expanded martensite/austenite during low-temperature carburization. Various experimental procedures to experimentally determine the concentration dependent diffusion coefficient of carbon in expanded austenite are evaluated. The most promising procedure...... powders and flakes. The nature of the decomposition products, carbides of the form M23C6 and M7C3, were evaluated by X-ray diffraction, light optical microscopy, scanning electron microscopy and thermodynamic modelling. The decomposition was found to be dependent on several parameters such as thermal...

  20. Prestack depth migration

    International Nuclear Information System (INIS)

    Postma, R.W.

    1991-01-01

    Two lines form the southern North Sea, with known velocity inhomogeneities in the overburden, have been pre-stack depth migrated. The pre-stack depth migrations are compared with conventional processing, one with severe distortions and one with subtle distortions on the conventionally processed sections. The line with subtle distortions is also compared with post-stack depth migration. The results on both lines were very successful. Both have already influenced drilling decisions, and have caused a modification of structural interpretation in the respective areas. Wells have been drilled on each of the lines, and well tops confirm the results. In fact, conventional processing led to incorrect locations for the wells, both of which were dry holes. The depth migrated sections indicate the incorrect placement, and on one line reveals a much better drilling location. This paper reports that even though processing costs are high for pre-stack depth migration, appropriate use can save millions of dollars in dry-hole expense

  1. Migration = cloning; aliasiing

    DEFF Research Database (Denmark)

    Hüttel, Hans; Kleist, Josva; Nestmann, Uwe

    1999-01-01

    In Obliq, a lexically scoped, distributed, object-oriented programming language, object migration was suggested as the creation of a copy of an object’s state at the target site, followed by turning the object itself into an alias, also called surrogate, for the remote copy. We consider the creat......In Obliq, a lexically scoped, distributed, object-oriented programming language, object migration was suggested as the creation of a copy of an object’s state at the target site, followed by turning the object itself into an alias, also called surrogate, for the remote copy. We consider...... the creation of object surrogates as an abstraction of the abovementioned style of migration. We introduce Øjeblik, a distribution-free subset of Obliq, and provide three different configuration-style semantics, which only differ in the respective aliasing model. We show that two of the semantics, one of which...... matches Obliq’s implementation, render migration unsafe, while our new proposal for a third semantics is provably safe. Our work suggests a straightforward repair of Obliq’s aliasing model such that it allows programs to safely migrate objects....

  2. Intergalactic dust and quasar distribution

    International Nuclear Information System (INIS)

    Soltan, A.

    1979-01-01

    Non-homogeneous intergalactic extinction may considerably affect the quasar distribution. Especially samples of quasars isolated on the basis of B-V colours are subject to this phenomenon. Apparent grouping and close pairs of quasars reported in the literature may be a result of intergalactic dust. Using surface distribution of faint blue objects selected by Hawkins and Reddish it is estimated that intergalactic extinction in B should reach approximately 1 mag out to the redshift of approximately 1. This is slightly larger than predicted by theory and comparable to the mean dust density derived from observations. (Author)

  3. The distribution of interstellar dust

    International Nuclear Information System (INIS)

    Clocchiatti, A.; Marraco, H.G.

    1986-01-01

    We propose the interstellar matter structural function as a tool to derive the features of the interstellar dust distribution. We study that function resolving some ideal dust distribution models. Later we describe the method used to find a reliable computing algorithm for the observational case. Finally, we describe the steps to build a model for the interstellar matter composed by spherically symmetrical clouds. The density distribution for each of these clouds is D(r) = D 0 .esup(-r/r 0 ) 2 . The preliminary results obtained are summarised. (author)

  4. Electrostatic Dust Detector with Improved Sensitivity

    International Nuclear Information System (INIS)

    Boyle, D.P.; Skinner, C.H.; Roquemore, A.L.

    2008-01-01

    Methods to measure the inventory of dust particles and to remove dust if it approaches safety limits will be required in next-step tokamaks such as ITER. An electrostatic dust detector, based on a fine grid of interlocking circuit traces, biased to 30 or 50 V, has been developed for the detection of dust on remote surfaces in air and vacuum environments. Gaining operational experience of dust detection on surfaces in tokamaks is important, however the level of dust generated in contemporary short-pulse tokamaks is comparatively low and high sensitivity is necessary to measure dust on a shot-by-shot basis. We report on modifications in the detection electronics that have increased the sensitivity of the electrostatic dust detector by a factor of up to 120, - a level suitable for measurements on contemporary tokamaks.

  5. Infrared Observations of Cometary Dust and Nuclei

    Science.gov (United States)

    Lisse, Carey

    2004-01-01

    This bibliography lists citations for publications published under the grant. Subjects of the publications include cometary dust, instellar and interplanetary dust, comet nuclei and comae, Comet Hale-Bopp, infrared observations of comets, mass loss, and comet break-up.

  6. The global distribution of mineral dust

    International Nuclear Information System (INIS)

    Tegen, I; Schepanski, K

    2009-01-01

    Dust aerosol particles produced by wind erosion in arid and semi arid regions affect climate and air quality, but the magnitude of these effects is largely unquantified. The major dust source regions include the Sahara, the Arabian and Asian deserts; global annual dust emissions are currently estimated to range between 1000 and 3000 Mt/yr. Dust aerosol can be transported over long distances of thousands of kilometers, e.g. from source regions in the Saharan desert over the North Atlantic, or from the Asian deserts towards the Pacific Ocean. The atmospheric dust load varies considerably on different timescales. While dust aerosol distribution and dust effects are important on global scales, they strongly depend on dust emissions that are controlled on small spatial and temporal scales.

  7. En fornemmelse for migration

    DEFF Research Database (Denmark)

    Schütze, Laura Maria

    Afhandlingen undersøger, hvordan sted, museets rolle som aktør og religion er relevante for produktionen af migration på Immigrantmuseet (2012) og i Københavns Museums udstilling At blive københavner (2010). Afhandlingen er baseret på udstillingsanalyse samt interview med relevant museumsfagligt......, anvendes som virkemidler til at nuancere migration og distancere udstillingen fra den offentlige debat om indvandring. Afhandlingen peger på, at produktionen af den nyere danske historie på museum er præget af et fravær af religion. Det skyldes, at de museumsfaglige praksisser og traditioner afspejler en...... identiteter, som vi tager for givet: nationer, byer, kvinder - såvel som migration og religion. Afhandlingen argumenterer følgelig for, at museernes produktion af (materiel) religion er et særdeles relevant, men kun ringe udforsket, genstandsfelt for religionssociologien....

  8. Exact solutions for rotating charged dust

    International Nuclear Information System (INIS)

    Islam, J.N.

    1984-01-01

    Earlier work by the author on rotating charged dust is summarized. An incomplete class of exact solutions for differentially rotating charged dust in Newton-Maxwell theory for the equal mass and charge case that was found earlier is completed. A new global exact solution for cylindrically symmetric differentially rotating charged dust in Newton-Maxwell theory is presented. Lastly, a new exact solution for cylindrically symmetric rigidly rotating charged dust in general relativity is given. (author)

  9. Studies of dust shells around stars

    International Nuclear Information System (INIS)

    Bedijn, P.J.

    1977-01-01

    This thesis deals with some aspects of circumstellar dust shells. This dust shell, emitting infrared radiation, is described by way of its absorptive and emissive properties as well as by the transfer of radiation through the dust shell itself. Model calculations are compared to experimental results and agree reasonably well. The author also discusses the dynamics of the extended shells of gas and dust around newly formed stars

  10. What's driving migration?

    Science.gov (United States)

    Kane, H

    1995-01-01

    During the 1990s investment in prevention of international or internal migration declined, and crisis intervention increased. The budgets of the UN High Commissioner for Refugees and the UN Development Program remained about the same. The operating assumption is that war, persecution, famine, and environmental and social disintegration are inevitable. Future efforts should be directed to stabilizing populations through investment in sanitation, public health, preventive medicine, land tenure, environmental protection, and literacy. Forces pushing migration are likely to increase in the future. Forces include depletion of natural resources, income disparities, population pressure, and political disruption. The causes of migration are not constant. In the past, migration occurred during conquests, settlement, intermarriage, or religious conversion and was a collective movement. Current migration involves mass movement of individuals and the struggle to survive. There is new pressure to leave poor squatter settlements and the scarcities in land, water, and food. The slave trade between the 1500s and the 1800s linked continents, and only 2-3 million voluntarily crossed national borders. Involuntary migration began in the early 1800s when European feudal systems were in a decline, and people sought freedom. Official refugees, who satisfy the strict 1951 UN definition, increased from 15 million in 1980 to 23 million in 1990 but remained a small proportion of international migrants. Much of the mass movement occurs between developing countries. Migration to developed countries is accompanied by growing intolerance, which is misinformed. China practices a form of "population transfer" in Tibet in order to dilute Tibetan nationalism. Colonization of countries is a new less expensive form of control over territory. Eviction of minorities is another popular strategy in Iraq. Public works projects supported by foreign aid displace millions annually. War and civil conflicts

  11. Unix Application Migration Guide

    CERN Document Server

    Microsoft. Redmond

    2003-01-01

    Drawing on the experience of Microsoft consultants working in the field, as well as external organizations that have migrated from UNIX to Microsoft® Windows®, this guide offers practical, prescriptive guidance on the issues you are likely to face when porting existing UNIX applications to the Windows operating system environment. Senior IT decision makers, network managers, and operations managers will get real-world guidance and best practices on planning and implementation issues to understand the different methods through which migration or co-existence can be accomplished. Also detailing

  12. Migrating for a Profession

    DEFF Research Database (Denmark)

    Olwig, Karen Fog

    2015-01-01

    a strong sense of agency and self-empowerment. In the post-WWII period, numerous Caribbean women trained in nursing at British hospitals that have been described as marred by race and gender related inequality and associated forms of exploitation. Yet, the nurses interviewed about this training emphasised......Youths from the Global South migrating for further education often face various forms of discrimination. This Caribbean case study discusses how conditions in the home country can provide a foundation for educational migration that helps the migrants overcome such obstacles and even develop...... in which it enabled these Caribbean women to stake out a new life for themselves....

  13. Radio frequency discharge with dust particles

    NARCIS (Netherlands)

    Chutov, Y. I.; W. J. Goedheer,; Kravchenko, O. Y.; Zuz, V. M.; Yan, M.; Martins, R.; Ferreira, I.; Fortunato, E.; Kroesen, G.

    2000-01-01

    A 1D PIC/MCC method has been developed for computer simulations of low-pressure RF discharges with dust particles using the method for dust-free discharges. A RF discharge in argon with dust particles distributed uniformly in the interelectrode gap is simulated at parameters providing a possibility

  14. Thirteen years of Aeolian dust dynamics in a desert region (Negev desert, Israel): analysis of horizontal and vertical dust flux, vertical dust distribution and dust grain size

    NARCIS (Netherlands)

    Offer, Z.Y.; Goossens, D.

    2004-01-01

    At Sede Boqer (northern Negev desert, Israel), aeolian dust dynamics have been measured during the period 1988–2000. This study focuses on temporal records of the vertical and horizontal dust flux, the vertical distribution of the dust particles in the atmosphere, and the grain size of the

  15. Dust Measurements Onboard the Deep Space Gateway

    Science.gov (United States)

    Horanyi, M.; Kempf, S.; Malaspina, D.; Poppe, A.; Srama, R.; Sternovsky, Z.; Szalay, J.

    2018-02-01

    A dust instrument onboard the Deep Space Gateway will revolutionize our understanding of the dust environment at 1 AU, help our understanding of the evolution of the solar system, and improve dust hazard models for the safety of crewed and robotic missions.

  16. Properties of interstellar dust in reflection nebulae

    International Nuclear Information System (INIS)

    Sellgren, K.

    1988-01-01

    Observations of interstellar dust in reflection nebulae are the closest analog in the interstellar medium to studies of cometary dust in our solar system. The presence of a bright star near the reflection nebula dust provides the opportunity to study both the reflection and emission characteristics of interstellar dust. At 0.1 to 1 micrometer, the reflection nebula emission is due to starlight scattered by dust. The albedo and scattering phase function of the dust is determined from observations of the scattered light. At 50 to 200 micrometers, thermal emission from the dust in equilibrium with the stellar radiation field is observed. The derived dust temperature determines the relative values of the absorption coefficient of the dust at wavelengths where the stellar energy is absorbed and at far infrared wavelengths where the absorbed energy is reradiated. These emission mechanisms directly relate to those seen in the near and mid infrared spectra of comets. In a reflection nebula the dust is observed at much larger distances from the star than in our solar system, so that the equilibrium dust temperature is 50 K rather than 300 K. Thus, in reflection nebulae, thermal emission from dust is emitted at 50 to 200 micrometer

  17. House dust extracts contain potent immunological adjuvants

    NARCIS (Netherlands)

    Beukelman, C.J.; Dijk, H. van; Aerts, P.C.; Rademaker, P.M.; Berrens, L.; Willers, J.M.N.

    1987-01-01

    A crude aqueous extract of house dust and two house dust subfractions were tested for adjuvant activity in a sensitivity assay performed in mice. Evidence is presented that house dust contains at least two potent immunological adjuvants. One of these, present in both subfractions, was probably

  18. Observed spectral features of dust

    International Nuclear Information System (INIS)

    Willner, S.P.

    1984-01-01

    The author concentrates on the observed properties of dust spectral features. Identifications, based on laboratory data, are given whenever plausible ones exist. There are a very large number of papers in the literature of even such a young field as infrared spectroscopy, and therefore the author refers only to the most recent paper on a topic or to another review. (Auth.)

  19. Meteors, meteorites and cosmic dust

    International Nuclear Information System (INIS)

    Lebedinets, V.N.

    1987-01-01

    The problem of meteorite origin and meteorite composition is discussed. Nowadays, most scientists suppose that the giant Oort cloud consisting of ice comet nuclei is the sourse of the meteor matter. A principle unity of the matter of meteorites falling to the Earth and cosmic dust is noted as well as that of meteorite bodies evaporating in the atmosphere and bearing meteors and bodies

  20. Occupational diseases of dust etiology

    International Nuclear Information System (INIS)

    Sokolik, L.I.; Shkondin, A.N.

    1981-01-01

    Detailed etiologic and clinico-roentgenological characteristics of pneumoconiosis, as widely spread occupational disease caused by different kinds of dust, are given. The course of pneumoconiosis is discussed depending on working conditions of patients after the disease had been ascertained, as well as its complications, taking into account roentgeno-morphological types of fibrosis and the stages of the disease [ru

  1. 75 FR 32142 - Combustible Dust

    Science.gov (United States)

    2010-06-07

    .... Contact Mat Chibbaro, P.E., Fire Protection Engineer, Office of Safety Systems, OSHA Directorate of..., and metals (such as aluminum and magnesium). Industries that may have combustible dust hazards include..., chemical manufacturing, textile manufacturing, furniture manufacturing, metal processing, fabricated metal...

  2. Trapping Dust to Form Planets

    Science.gov (United States)

    Kohler, Susanna

    2017-10-01

    Growing a planet from a dust grain is hard work! A new study explores how vortices in protoplanetary disks can assist this process.When Dust Growth FailsTop: ALMA image of the protoplanetary disk of V1247 Orionis, with different emission components labeled. Bottom: Synthetic image constructed from the best-fit model. [Kraus et al. 2017]Gradual accretion onto a seed particle seems like a reasonable way to grow a planet from a grain of dust; after all, planetary embryos orbit within dusty protoplanetary disks, which provides them with plenty of fuel to accrete so they can grow. Theres a challenge to this picture, though: the radial drift problem.The radial drift problem acknowledges that, as growing dust grains orbit within the disk, the drag force on them continues to grow as well. For large enough dust grains perhaps around 1 millimeter the drag force will cause the grains orbits to decay, and the particles drift into the star before they are able to grow into planetesimals and planets.A Close-Up Look with ALMASo how do we overcome the radial drift problem in order to form planets? A commonly proposed mechanism is dust trapping, in which long-lived vortices in the disk trap the dust particles, preventing them from falling inwards. This allows the particles to persist for millions of years long enough to grow beyond the radial drift barrier.Observationally, these dust-trapping vortices should have signatures: we would expect to see, at millimeter wavelengths, specific bright, asymmetric structures where the trapping occurs in protoplanetary disks. Such disk structures have been difficult to spot with past instrumentation, but the Atacama Large Millimeter/submillimeter Array (ALMA) has made some new observations of the disk V1247 Orionis that might be just what were looking for.Schematic of the authors model for the disk of V1247 Orionis. [Kraus et al. 2017]Trapped in a Vortex?ALMAs observations of V1247 Orionis are reported by a team of scientists led by Stefan

  3. Migrating the Light

    DEFF Research Database (Denmark)

    Sørensen, Bent

    The migration of Blaga’s universalist, even centralist poems from Romanian of the first third of the 20th C. into American of the first fifth of the 21st C. illustrates the uses of Pierre Joris’s nomadic methods. My translations of Blaga read well for a teenage audience whose only exposure to lit...

  4. Describing migration spatial structure

    NARCIS (Netherlands)

    Rogers, A; Willekens, F; Little, J; Raymer, J

    The age structure of a population is a fundamental concept in demography and is generally depicted in the form of an age pyramid. The spatial structure of an interregional system of origin-destination-specific migration streams is, however, a notion lacking a widely accepted definition. We offer a

  5. Brain Migration Revisited

    Science.gov (United States)

    Vinokur, Annie

    2006-01-01

    The "brain drain/brain gain" debate has been going on for the past 40 years, with irresolvable theoretical disputes and unenforceable policy recommendations that economists commonly ascribe to the lack of reliable empirical data. The recent report of the World Bank, "International migration, remittances and the brain drain", documents the…

  6. Dispersal and migration

    Directory of Open Access Journals (Sweden)

    Schwarz, C.

    2004-06-01

    Full Text Available Ringing of birds unveiled many aspects of avian migration and dispersal movements. However, there is even much more to be explored by the use of ringing and other marks. Dispersal is crucial in understanding the initial phase of migration in migrating birds as it is to understand patterns and processes of distribution and gene flow. So far, the analysis of migration was largely based on analysing spatial and temporal patters of recoveries of ringed birds. However, there are considerable biases and pitfalls in using recoveries due to spatial and temporal variation in reporting probabilities. Novel methods are required for future studies separating the confounding effects of spatial and temporal heterogeneity of recovery data and heterogeneity of the landscape as well. These novel approaches should aim a more intensive and novel use of the existing recovery data by taking advantage of, for instance, dynamic and multistate modeling, should elaborate schemes for future studies, and should also include other marks that allow a more rapid data collection, like telemetry, geolocation and global positioning systems, and chemical and molecular markers. The latter appear to be very useful in the delineating origin of birds and connectivity between breeding and non–breeding grounds. Many studies of migration are purely descriptive. However, King and Brooks (King & Brooks, 2004 examine if movement patterns of dolphins change after the introduction of a gillnet ban. Bayesian methods are an interesting approach to this problem as they provide a meaningful measure of the probability that such a change occurred rather than simple yes/no response that is often the result of classical statistical methods. However, the key difficulty of a general implementation of Bayesian methods is the complexity of the modelling —there is no general userfriendly package that is easily accessible to most scientists. Drake and Alisauskas (Drake & Alisauskas, 2004 examine the

  7. Migration and Africa

    DEFF Research Database (Denmark)

    Zoppi, Marco

    2014-01-01

    European powers imposed the nation-state on Africa through colonialism. But even after African independencies, mainstream discourses and government policies have amplified the idea that sedentariness and the state are the only acceptable mode of modernity. Migration is portrayed as a menace...

  8. Migration as Adventure

    DEFF Research Database (Denmark)

    Olwig, Karen Fog

    2018-01-01

    Narratives of adventure constitute a well-established convention of describing travel experiences, yet the significance of this narrative genre in individuals’ accounts of their migration and life abroad has been little investigated. Drawing on Simmel and Bakhtin, among others, this article...

  9. Digitizing migration heritage

    DEFF Research Database (Denmark)

    Marselis, Randi

    2011-01-01

    Museums are increasingly digitizing their collections and making them available to the public on-line. Creating such digital resources may become means for social inclusion. For museums that acknowledge migration history and cultures of ethnic minority groups as important subjects in multiethnic...

  10. The politicisation of migration

    NARCIS (Netherlands)

    van der Brug, W.; D' Amato, G.; Berkhout, J.; Ruedin, D.

    2015-01-01

    Why are migration policies sometimes heavily contested and high on the political agenda? And why do they, at other moments and in other countries, hardly lead to much public debate? The entrance and settlement of migrants in Western Europe has prompted various political reactions. In some countries

  11. Practical Data Migration

    CERN Document Server

    Morris, Johny

    2012-01-01

    This book is for executives and practitioners tasked with the movement of data from old systems to a new repository. It uses a series of steps guaranteed to get the reader from an empty new system to one that is working and backed by the user population. Using this proven methodology will vastly increase the chances of a successful migration.

  12. Migration pathways in soils

    International Nuclear Information System (INIS)

    Gronow, J.R.

    1986-01-01

    This study looked at diffusive migration through three types of deformation; the projectile pathways, hydraulic fractures of the sediments and faults, and was divided into three experimental areas: autoradiography, the determination of diffusion coefficients and electron microscopy of model projectile pathways in clay. For the autoradiography, unstressed samples were exposed to two separate isotopes, Pm-147 (a possible model for Am behaviour) and the poorly sorbed iodide-125. The results indicated that there was no enhanced migration through deformed kaolin samples nor through fractured Great Meteor East (GME) sediment, although some was evident through the projectile pathways in GME and possibly through the GME sheared samples. The scanning electron microscopy of projectile pathways in clay showed that emplacement of a projectile appeared to have no effect on the orientation of particles at distances greater than two projectile radii from the centre of a projectile pathway. It showed that the particles were not simply aligned with the direction of motion of the projectile but that, the closer to the surface of a particular pathway, the closer the particles lay to their original orientation. This finding was of interest from two points of view: i) the ease of migration of a pollutant along the pathway, and ii) possible mechanisms of hole closure. It was concluded that, provided that there is no advective migration, the transport of radionuclides through sediments containing these defects would not be significantly more rapid than in undeformed sediments. (author)

  13. International Migration of Couples

    DEFF Research Database (Denmark)

    Junge, Martin; Munk, Martin D.; Nikolka, Till

    2018-01-01

    Migrant self-selection is important to labor markets and public finances in both origin and destination countries. We develop a theoretical model regarding the migration of dual-earner couples and test it using population-wide administrative data from Denmark. Our model predicts that the probabil...

  14. Cosmological simulation with dust formation and destruction

    Science.gov (United States)

    Aoyama, Shohei; Hou, Kuan-Chou; Hirashita, Hiroyuki; Nagamine, Kentaro; Shimizu, Ikkoh

    2018-06-01

    To investigate the evolution of dust in a cosmological volume, we perform hydrodynamic simulations, in which the enrichment of metals and dust is treated self-consistently with star formation and stellar feedback. We consider dust evolution driven by dust production in stellar ejecta, dust destruction by sputtering, grain growth by accretion and coagulation, and grain disruption by shattering, and treat small and large grains separately to trace the grain size distribution. After confirming that our model nicely reproduces the observed relation between dust-to-gas ratio and metallicity for nearby galaxies, we concentrate on the dust abundance over the cosmological volume in this paper. The comoving dust mass density has a peak at redshift z ˜ 1-2, coincident with the observationally suggested dustiest epoch in the Universe. In the local Universe, roughly 10 per cent of the dust is contained in the intergalactic medium (IGM), where only 1/3-1/4 of the dust survives against dust destruction by sputtering. We also show that the dust mass function is roughly reproduced at ≲ 108 M⊙, while the massive end still has a discrepancy, which indicates the necessity of stronger feedback in massive galaxies. In addition, our model broadly reproduces the observed radial profile of dust surface density in the circum-galactic medium (CGM). While our model satisfies the observational constraints for the dust extinction on cosmological scales, it predicts that the dust in the CGM and IGM is dominated by large (>0.03 μm) grains, which is in tension with the steep reddening curves observed in the CGM.

  15. Respiratory Toxicity of Lunar Highland Dust

    Science.gov (United States)

    James, John T.; Lam, Chiu-wing; Wallace, William T.

    2009-01-01

    Lunar dust exposures occurred during the Apollo missions while the crew was on the lunar surface and especially when microgravity conditions were attained during rendezvous in lunar orbit. Crews reported that the dust was irritating to the eyes and in some cases respiratory symptoms were elicited. NASA s vision for lunar exploration includes stays of 6 months on the lunar surface hence the health effects of periodic exposure to lunar dust need to be assessed. NASA has performed this assessment with a series of in vitro and in vivo tests on authentic lunar dust. Our approach is to "calibrate" the intrinsic toxicity of lunar dust by comparison to a nontoxic dust (TiO2) and a highly toxic dust (quartz) using intratrachael instillation of the dusts in mice. A battery of indices of toxicity is assessed at various time points after the instillations. Cultures of selected cells are exposed to test dusts to assess the adverse effects on the cells. Finally, chemical systems are used to assess the nature of the reactivity of various dusts and to determine the persistence of reactivity under various environmental conditions that are relevant to a space habitat. Similar systems are used to assess the dissolution of the dust. From these studies we will be able to set a defensible inhalation exposure standard for aged dust and predict whether we need a separate standard for reactive dust. Presently-available data suggest that aged lunar highland dust is slightly toxic, that it can adversely affect cultured cells, and that the surface reactivity induced by grinding the dust persists for a few hours after activation.

  16. Design and development of a dust dispersion chamber to quantify the dispersibility of rock dust.

    Science.gov (United States)

    Perera, Inoka E; Sapko, Michael J; Harris, Marcia L; Zlochower, Isaac A; Weiss, Eric S

    2016-01-01

    Dispersible rock dust must be applied to the surfaces of entries in underground coal mines in order to inert the coal dust entrained or made airborne during an explosion and prevent propagating explosions. 30 CFR. 75.2 states that "… [rock dust particles] when wetted and dried will not cohere to form a cake which will not be dispersed into separate particles by a light blast of air …" However, a proper definition or quantification of "light blast of air" is not provided. The National Institute for Occupational Safety and Health (NIOSH) has, consequently, designed a dust dispersion chamber to conduct quantitative laboratory-scale dispersibility experiments as a screening tool for candidate rock dusts. A reproducible pulse of air is injected into the chamber and across a shallow tray of rock dust. The dust dispersed and carried downwind is monitored. The mass loss of the dust tray and the airborne dust measurements determine the relative dispersibility of the dust with respect to a Reference rock dust. This report describes the design and the methodology to evaluate the relative dispersibility of rock dusts with and without anti-caking agents. Further, the results of this study indicate that the dispersibility of rock dusts varies with particle size, type of anti-caking agent used, and with the untapped bulk density. Untreated rock dusts, when wetted and dried forming a cake that was much less dispersible than the reference rock dust used in supporting the 80% total incombustible content rule.

  17. Step by step in dust control

    Energy Technology Data Exchange (ETDEWEB)

    Archer, N. [Arch Environmental Equipment, Inc. (United States)

    2003-05-01

    The paper examines the different stages in identifying delegating and controlling dust before it becomes a serious problem for a facility. Material handling, processing, storage and traffic are the major dust producing sources. All industries that convey dry, light material need to install a dust control system. The confine-seal-suppress method of dust control has provided excellent results in numerous applications, only with the combination of all three will maximum dust control. When a system is properly engineered and correctly installed, meeting the EPA Government standards becomes very easy, and is necessary in to the operation of a quality facility. 5 photos.

  18. Dust bands in the asteroid belt

    International Nuclear Information System (INIS)

    Sykes, M.V.; Greenberg, R.; Dermott, S.F.; Nicholson, P.D.; Burns, J.A.

    1989-01-01

    This paper describes the original IRAS observations leading to the discovery of the three dust bands in the asteroid belt and the analysis of data. Special attention is given to an analytical model of the dust band torus and to theories concerning the origin of the dust bands, with special attention given to the collisional equilibrium (asteroid family), the nonequilibrium (random collision), and the comet hypotheses of dust-band origin. It is noted that neither the equilibrium nor nonequilibrium models, as currently formulated, present a complete picture of the IRAS dust-band observations. 32 refs

  19. Linear Alkylbenzenesulfonates in indoor Floor Dust

    DEFF Research Database (Denmark)

    Madsen, Jørgen Øgaard; Wolkoff, Peder; Madsen, Jørgen Øgaard

    1999-01-01

    The amount of Linear Alkylbenzenesulfonates (LAS) in the particle fraction of floor dust sampled from 7 selected public buildings varied between 34 and 1500 microgram per gram dust, while the contents of the fibre fractions generally were higher with up to 3500 microgram LAS/g dust. The use...... of a cleaning agent with LAS resulted in an increase of the amount of LAS in the floor dust after floor wash relative to just before floor wash. However, the most important source of LAS in the indoor floor dust appears to be residues of detergent in clothing. Thus, a newly washed shirt contained 2960 microgram...

  20. Time-Dependent Dust Formation in Novae

    Directory of Open Access Journals (Sweden)

    Kyung-Won Suh

    1991-06-01

    Full Text Available The dust formation processes in novae are investigated with close attention to recent infrared observations. Using mainly the classical nucleation theory, we have calculated the time scales of dust formation and growth in the environments of novae. Those time scales roughly resemble the typical observations. We have classified the dust-forming novae into three classes according to their explosion properties and the thermodynamic properties of dust grains. Oxygen grains from much later than carbon grains because of their thermodynamic properties. The effect of grain formation to the efficiency of stellar winds to drive the material outward is tested with newly obtained Planck mean values of dust grains.

  1. Numerical Prediction of Dust. Chapter 10

    Science.gov (United States)

    Benedetti, Angela; Baldasano, J. M.; Basart, S.; Benincasa, F.; Boucher, O.; Brooks, M.; Chen, J. P.; Colarco, P. R.; Gong, S.; Huneeus, N.; hide

    2013-01-01

    Covers the whole breadth of mineral dust research, from a scientific perspective Presents interdisciplinary work including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies Explores the role of dust as a player and recorder of environmental change This volume presents state-of-the-art research about mineral dust, including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies. Dust research is a new, dynamic and fast-growing area of science and due to its multiple roles in the Earth system, dust has become a fascinating topic for many scientific disciplines. Aspects of dust research covered in this book reach from timescales of minutes (as with dust devils, cloud processes, and radiation) to millennia (as with loess formation and oceanic sediments), making dust both a player and recorder of environmental change. The book is structured in four main parts that explore characteristics of dust, the global dust cycle, impacts of dust on the Earth system, and dust as a climate indicator. The chapters in these parts provide a comprehensive, detailed overview of this highly interdisciplinary subject. The contributions presented here cover dust from source to sink and describe all the processes dust particles undergo while travelling through the atmosphere. Chapters explore how dust is lifted and transported, how it affects radiation, clouds, regional circulations, precipitation and chemical processes in the atmosphere, and how it deteriorates air quality. The book explores how dust is removed from the atmosphere by gravitational settling, turbulence or precipitation, how iron contained in dust fertilizes terrestrial and marine ecosystems, and about the role that dust plays in human health. We learn how dust is observed, simulated using computer models and forecast. The book also details the role of dust deposits for climate reconstructions

  2. Dust removal system for fusion experimental reactors

    International Nuclear Information System (INIS)

    Onozuka, M.; Ueda, Y.; Takahashi, K.; Oda, Y.; Seki, Y.; Ueda, S.; Aoki, I.

    1995-01-01

    Development of a dust removal system using static electricity has been conducted. It is envisioned that the system can collect and transport dust under vacuum. In the system, the dust is charged by dielectric polarization and floated by an electrostatic attraction force that is generated by the DC electric field. The dust is then transported by the electric curtain formed by the three-phase AC electric field. Experimental investigation has been conducted to examine the characteristics of the system. Current research results indicate that the dust removal system using static electricity can be used for fusion experimental reactors

  3. Dust removal system for fusion experimental reactors

    Energy Technology Data Exchange (ETDEWEB)

    Onozuka, M.; Ueda, Y.; Takahashi, K.; Oda, Y. [Mitsubishi Heavy Industries, Ltd., Yokohama (Japan); Seki, Y.; Ueda, S.; Aoki, I. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan)

    1995-12-31

    Development of a dust removal system using static electricity has been conducted. It is envisioned that the system can collect and transport dust under vacuum. In the system, the dust is charged by dielectric polarization and floated by an electrostatic attraction force that is generated by the DC electric field. The dust is then transported by the electric curtain formed by the three-phase AC electric field. Experimental investigation has been conducted to examine the characteristics of the system. Current research results indicate that the dust removal system using static electricity can be used for fusion experimental reactors.

  4. Globalization, Migration and Development

    Directory of Open Access Journals (Sweden)

    George, Susan

    2002-01-01

    Full Text Available EnglishMigration may become the most important branch of demography in the earlydecades of the new millennium in a rapidly globalizing world. This paper discusses the causes, costsand benefits of international migration to countries of the South and North, and key issues of commonconcern. International migration is as old as national boundaries, though its nature, volume,direction, causes and consequences have changed. The causes of migration are rooted in the rate ofpopulation growth and the proportion of youth in the population, their education and training,employment opportunities, income differentials in society, communication and transportationfacilities, political freedom and human rights and level of urbanization. Migration benefits the Souththrough remittances of migrants, improves the economic welfare of the population (particularly womenof South countries generally, increases investment, and leads to structural changes in the economy.However, emigration from the South has costs too, be they social or caused by factors such as braindrain. The North also benefits by migration through enhancement of economic growth, development ofnatural resources, improved employment prospects, social development and through exposure toimmigrants' new cultures and lifestyles. Migration also has costs to the North such as of immigrantintegration, a certain amount of destabilization of the economy, illegal immigration, and socialproblems of discrimination and exploitation. Issues common to both North and South include impact onprivate investment, trade, international cooperation, and sustainable development. Both North andSouth face a dilemma in seeking an appropriate balance between importing South's labour or itsproducts and exporting capital and technology from the North.FrenchLa migration est sans doute devenue la partie la plus importante de la démographie des premières décennies du nouveau millénaire dans un monde qui change rapidement. Ce

  5. Migration and Remittances : Recent Developments and Outlook - Transit Migration

    OpenAIRE

    World Bank Group

    2018-01-01

    This Migration and Development Brief reports global trends in migration and remittance flows, as well as developments related to the Global Compact on Migration (GCM), and the Sustainable Development Goal (SDG) indicators for volume of remittances as percentage of gross domestic product (GDP) (SDG indicator 17.3.2), reducing remittance costs (SDG indicator 10.c.1) and recruitment costs (SD...

  6. ORIGIN OF DUST AROUND V1309 SCO

    International Nuclear Information System (INIS)

    Zhu, Chunhua; Lü, Guoliang; Wang, Zhaojun

    2013-01-01

    The origin of dust grains in the interstellar medium is still an unanswered problem. Nicholls et al. found the presence of a significant amount of dust around V1309 Sco, which may originate from the merger of a contact binary. We investigate the origin of dust around V1309 Sco and suggest that these dust grains are produced in the binary-merger ejecta. By means of the AGBDUST code, we estimate that ∼5.2 × 10 –4 M ☉ dust grains are produced with a radii of ∼10 –5 cm. These dust grains are mainly composed of silicate and iron grains. Because the mass of the binary merger ejecta is very small, the contribution of dust produced by binary merger ejecta to the overall dust production in the interstellar medium is negligible. However, it is important to note that the discovery of a significant amount of dust around V1309 Sco offers a direct support for the idea that common-envelope ejecta provides an ideal environment for dust formation and growth. Therefore, we confirm that common envelope ejecta can be important source of cosmic dust

  7. Engineering-scale dust control experiments

    International Nuclear Information System (INIS)

    Winberg, M.R.; Pawelko, R.J.; Jacobs, N.C.; Thompson, D.N.

    1990-12-01

    This report presents the results of engineering scale dust-control experiments relating to contamination control during handling of transuranic waste. These experiments focused on controlling dust during retrieval operations of buried waste where waste and soil are intimately mixed. Sources of dust generation during retrieval operations include digging, dumping, and vehicle traffic. Because contaminants are expected to attach to soil particles and move with the generated dust, control of the dust spread may be the key to contamination control. Dust control techniques examined in these experiments include the use of misting systems, soil fixatives, and dust suppression agents. The Dryfog Ultrasonic Misting Head, manufactured by Sonics, Incorporated, and ENTAC, an organic resin derived from tree sap manufactured by ENTAC Corporation, were tested. The results of the experiments include product performance and recommended application methods. 19 figs., 7 refs., 6 tabs

  8. COSMIC DUST AGGREGATION WITH STOCHASTIC CHARGING

    International Nuclear Information System (INIS)

    Matthews, Lorin S.; Hyde, Truell W.; Shotorban, Babak

    2013-01-01

    The coagulation of cosmic dust grains is a fundamental process which takes place in astrophysical environments, such as presolar nebulae and circumstellar and protoplanetary disks. Cosmic dust grains can become charged through interaction with their plasma environment or other processes, and the resultant electrostatic force between dust grains can strongly affect their coagulation rate. Since ions and electrons are collected on the surface of the dust grain at random time intervals, the electrical charge of a dust grain experiences stochastic fluctuations. In this study, a set of stochastic differential equations is developed to model these fluctuations over the surface of an irregularly shaped aggregate. Then, employing the data produced, the influence of the charge fluctuations on the coagulation process and the physical characteristics of the aggregates formed is examined. It is shown that dust with small charges (due to the small size of the dust grains or a tenuous plasma environment) is affected most strongly

  9. THE ROMANIAN MIGRATIONAL EVOLUTION PHENOMENON

    Directory of Open Access Journals (Sweden)

    Cristian Raluca

    2009-05-01

    Full Text Available In our contemporary democratic society the migration phenomenon meets unknown valences in any previous societies. Free will and right to self-determination, much exploited by the XX century society., raised the possibility of interpretation of migration

  10. Croquet & lawn bowls

    CERN Multimedia

    Croquet & lawn bowls

    2011-01-01

    Croquet The season is well underway and several events have taken place: the Opening Event on 30th April, a PRO-AM doubles tournament, was won by Danny Davids in May the Swiss team of Ian Sexton, Norman Eatough, Danny Davids and Dave Underhill won the Rheingold Pokal at CERN in resounding fashion, with 33 wins against Germany’s 13 and Austria’s 8. in June the Swiss team of Ian Sexton, Norman Eatough and Dave Underhill competed in the European Team Championship in Cheltenham, England, in May, coming 2nd in the Continental Nations’ Trophy behind Spain and 6th overall on July 2nd, Norman Eatough won the Swiss Golf croquet Handicap championship on July 8th Barbara Perkins won the Women’s Swiss Golf croquet championship, for the third successive year on July 10th, Ian Sexton won the Swiss Golf croquet championship in mid-July, Dave Underhill is competing in the World Golf croquet championship in London. The English Croquet Association team will play the Swiss ...

  11. Transabdominal bowl sonography

    DEFF Research Database (Denmark)

    Wilkens, Rune; Strandberg, Charlotte

    2014-01-01

    This focused review describes the current use and future perspectives regarding transabdominal bowel sonography (TABS). The technique for B-mode and Doppler is described and the use of ultrasound contrast and elastography is discussed. Pathology and subsequent imaging findings are focused on appe...... on appendicitis, diverticulitis, inflammatory bowel diseases and within paediatric conditions along with other common intestinal pathology. In conclusion we find that TABS is a fast, efficient, low-cost and non-ionization imaging technique without any patient discomfort....

  12. International migration and the gender

    OpenAIRE

    Koropecká, Markéta

    2010-01-01

    My bachelor thesis explores the connection between international migration and gender. Gender, defined as a social, not a biological term, has a huge impact on the migration process. Statistics and expert studies that have been gender sensitive since 1970s demonstrate that women form half of the amount of the international migrants depending on the world region and representing a wide range of the kinds of international migration: family formation and reunification, labour migration, illegal ...

  13. Atmospheric dust contribution to budget of U-series nuclides in weathering profiles. The Mount Cameroon volcano

    Science.gov (United States)

    Pelt, E.; Chabaux, F. J.; Innocent, C.; Ghaleb, B.

    2009-12-01

    Analysis of U-series nuclides in weathering profiles is developed today for constraining time scale of soil and weathering profile formation (e.g., Chabaux et al., 2008). These studies require the understanding of U-series nuclides sources and fractionation in weathering systems. For most of these studies the impact of aeolian inputs on U-series nuclides in soils is usually neglected. Here, we propose to discuss such an assumption, i.e., to evaluate the impact of dust deposition on U-series nuclides in soils, by working on present and paleo-soils collected on the Mount Cameroon volcano. Recent Sr, Nd, Pb isotopic analyses performed on these samples have indeed documented significant inputs of Saharan dusts in these soils (Dia et al., 2006). We have therefore analyzed 238U-234U-230Th nuclides in the same samples. Comparison of U-Th isotopic data with Sr-Nd-Pb isotopic data indicates a significant impact of the dust input on the U and Th budget of the soils, around 10% for both U and Th. Using Sr-Nd-Pb isotopic data of Saharan dusts given by Dia et al. (2006) we estimate U-Th concentrations and U-Th isotope ratios of dusts compatible with U-Th data obtained on Saharan dusts collected in Barbados (Rydell H.S. and Prospero J.M., 1972). However, the variations of U/Th ratios along the weathering profiles cannot be explained by a simple mixing scenario between material from basalt and from the defined atmospheric dust pool. A secondary uranium migration associated with chemical weathering has affected the weathering profiles. Mass balance calculation suggests that U in soils from Mount Cameroon is affected at the same order of magnitude by both chemical migration and dust accretion. Nevertheless, the Mount Cameroon is a limit case were large dust inputs from continental crust of Sahara contaminate basaltic terrain from Mount Cameroon volcano. Therefore, this study suggests that in other contexts were dust inputs are lower, or the bedrocks more concentrated in U and Th

  14. The commercialization of migration.

    Science.gov (United States)

    Abrera-mangahas, M A

    1989-01-01

    International migration is not new to the Philippines. In the recent outflow of contract workers to the Middle East, there is a shift from individual and family initiated migrations to the more organized, highly commercial variety. While profit-taking intermediaries have played some role in the past, the increase in the number and influence of these intermediaries has altered the story of migration decision-making. In 1975, the signing of the bilateral labor agreement between the governments of Iran and the Philippines signalled the rising demand for Filipino contract workers. From 1970 to 1975, the number of Asian migrant workers in the Gulf countries rose from about 120,000 to 370,000. These figures rose dramatically to 3.3 million in 1985. The growing share of organized and commercialized migration has altered migration decision making. Primarily, intermediaries are able to broaden access to foreign job and high wage opportunities. Commercialization effectively raises the transaction costs for contract migration. Studies on recruitment costs and fees show that self-solicited foreign employment costs less than employment obtained through recruitment agents and intermediaries. The difference in the 2 prices is due, not only to overhead costs of intermediation, but more importantly to the rent exacted by agents from having job information and placement rights. In the Philippines in October 1987 the average placement fee was P8000, greatly exceeding the mandated maximum fee level of P5000. This average is understated because the computation includes the 17% who do not pay any fees. The widespread and popular view of recruitment intermediaries is negative, dominated by images of abuses and victims. Private intermediaries and the government bureaucracy need each other. Intermediaries need government; their consistent demand for incentives and protection is indicative. On the other hand, government expands its supervision of control of overseas employment via the

  15. Are Dogs That Are Fed from a Raised Bowl at an Increased Risk of Gastric Dilation Volvulus Compared with Floor-Fed Dogs?

    Directory of Open Access Journals (Sweden)

    Louise Anne Buckley

    2017-01-01

    Full Text Available There are only two studies that study the effect of raised feeders on the risk of Gastric Dilatation Volvulus (GDV and their findings conflict. Only one study found a significant effect of feeder height, with large and giant breeds fed from a raised feeder being at an increased risk of GDV floor fed dogs. However, these authors found that, where the feeder was raised, the height of the feeder that increased the GDV risk was affected by the size of the dog. Large breed dogs were more likely to develop a GDV if fed from a bowl ≤ 1 foot tall, whereas giant breed dogs were more likely to develop a GDV if fed from a bowl > 1 foot tall. No studies found that feeding from a raised feeder reduced the risk of GDV relative to feeding from the floor. Therefore, the safest option in the absence of further evidence is to advise that owners of ‘at risk’ dogs feed from a feeder on the floor. This may not reduce the risk of GDV, but there is no evidence to suggest that it will increase the risk. 

  16. Clinical use of Nintendo Wii bowling simulation to decrease fall risk in an elderly resident of a nursing home: a case report.

    Science.gov (United States)

    Clark, Robert; Kraemer, Theresa

    2009-01-01

    Of the estimated 1.7 million residents of nursing homes in the United States, approximately half fall annually; and 11% of these sustain injury. This is twice the rate for persons dwelling in the community. By addressing fall risk, physical therapists have an opportunity to reduce falls which are the leading cause of injury deaths, as well as the most common cause of nonfatal injuries for older adults in the United States. This case report examines the effect of a novel interactive video game intervention to address balance dysfunction in an elderly resident of a nursing home who was at risk for falls. The patient is an 89-year-old resident diagnosed with an unspecified balance disorder and a history of multiple falls. Self reports of gait abnormalities, scores on several clinical measures, and her fall history classified her as having substantial risk for future falls. A nontraditional approach to balance training, employing the Nintendo Wii bowling simulation, was used as intervention for this patient's balance disorder. After 6 one-hour treatment sessions, the patient's Berg Balance Score improved from 48 to 53. On the Dynamic Gait Index, the patient improved her score from 19 to 21. The patient's Timed Up and Go Test improved from 14.9 to 10.5 seconds, all suggesting a reduced risk of falling. The patient's ABC Score improved from 88 to 90%. Physical therapy intervention, using the Nintendo Wii bowling simulation, may have decreased fall risk for this individual.

  17. Coupling Mars' Dust and Water Cycles: Effects on Dust Lifting Vigor, Spatial Extent and Seasonality

    Science.gov (United States)

    Kahre, M. A.; Hollingsworth, J. L.; Haberle, R. M.; Montmessin, F.

    2012-01-01

    The dust cycle is an important component of Mars' current climate system. Airborne dust affects the radiative balance of the atmosphere, thus greatly influencing the thermal and dynamical state of the atmosphere. Dust raising events on Mars occur at spatial scales ranging from meters to planet-wide. Although the occurrence and season of large regional and global dust storms are highly variable from one year to the next, there are many features of the dust cycle that occur year after year. Generally, a low-level dust haze is maintained during northern spring and summer, while elevated levels of atmospheric dust occur during northern autumn and winter. During years without global-scale dust storms, two peaks in total dust loading were observed by MGS/TES: one peak occurred before northern winter solstice at Ls 200-240, and one peak occurred after northern winter solstice at L(sub s) 305-340. These maxima in dust loading are thought to be associated with transient eddy activity in the northern hemisphere, which has been observed to maximize pre- and post-solstice. Interactive dust cycle studies with Mars General Circulation Models (MGCMs) have included the lifting, transport, and sedimentation of radiatively active dust. Although the predicted global dust loadings from these simulations capture some aspects of the observed dust cycle, there are marked differences between the simulated and observed dust cycles. Most notably, the maximum dust loading is robustly predicted by models to occur near northern winter solstice and is due to dust lifting associated with down slope flows on the flanks of the Hellas basin. Thus far, models have had difficulty simulating the observed pre- and post- solstice peaks in dust loading. Interactive dust cycle studies typically have not included the formation of water ice clouds or their radiative effects. Water ice clouds can influence the dust cycle by scavenging dust from atmosphere and by interacting with solar and infrared radiation

  18. Youth Labor Migration in Nepal

    OpenAIRE

    Bossavie, Laurent; Denisova, Anastasiya

    2018-01-01

    This descriptive study investigates internal and external labor migration by Nepalese youth. External labor migration is separated into the flow to India, which is unregulated, and the flow to other countries, which typically takes the form of temporary contract migration to countries with bilateral labor agreements with Nepal (referred to in Nepal as foreign employment). The study finds t...

  19. Musei del migration heritage / Migration heritage museums

    Directory of Open Access Journals (Sweden)

    Patrizia Dragoni

    2015-01-01

    Since the second half of the 1960s of the 20th century, a profound cultural innovation was accompanied to the radical change in the social, political and economic climate. The anthropological notion of culture as opposed to idealistic vision, the unusual and strong interest in material culture, the enunciation of the concept of cultural property by the Franceschini Commission, the luck of the Public History bring a change of the disciplinary statutes of historical sciences, which begin to attend to social history, focusing on the spontaneous sources of information and initiating experiences of oral history. To all this a remarkable transformation of the themes and of the social function of museums is added. This paper illustrates, in relation to this more general context, the foundation and the dissemination of museums dedicated to the history of migration in Italy and in the world, enunciates their possible social utility for the integration of present migrants in Italy and illustrates, by way of example, the museum recently opened in Recanati.

  20. Religion, migration og integration

    DEFF Research Database (Denmark)

    Borup, Jørn

    2010-01-01

    Sammenhængen mellem religion og integration har de sidste år været genstand for debat. Artiklen kommer ind på begreber og sammenhænge relateret til området (migration, diaspora, assimilation, etnicitet, kultur) og ser på religionens mulige rolle som negativ eller positiv ressource i integrationss......Sammenhængen mellem religion og integration har de sidste år været genstand for debat. Artiklen kommer ind på begreber og sammenhænge relateret til området (migration, diaspora, assimilation, etnicitet, kultur) og ser på religionens mulige rolle som negativ eller positiv ressource i...

  1. House Dust Mite Respiratory Allergy

    DEFF Research Database (Denmark)

    Calderón, Moisés A; Kleine-Tebbe, Jörg; Linneberg, Allan

    2015-01-01

    Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence on the e......Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence...... not extend beyond the end of treatment. Finally, allergen immunotherapy has a poor but improving evidence base (notably on sublingual tablets) and its benefits last after treatment ends. This review identifies needs for deeper physician knowledge on the extent and impact of HDM allergy in respiratory disease...... and therapy of HDM respiratory allergy in practice....

  2. Grain boundary migration

    International Nuclear Information System (INIS)

    Dimitrov, O.

    1975-01-01

    Well-established aspects of grain-boundary migration are first briefly reviewed (influences of driving force, temperature, orientation and foreign atoms). Recent developments of the experimental methods and results are then examined, by considering the various driving of resistive forces acting on grain boundaries. Finally, the evolution in the theoretical models of grain-boundary motion is described, on the one hand for ideally pure metals and, on the other hand, in the presence of solute impurity atoms [fr

  3. Ventriculoperitoneal Shunt Migration

    Directory of Open Access Journals (Sweden)

    Justin P Puller

    2017-01-01

    Full Text Available History of present illness: A 40-year-old female presented to our ED with left upper abdominal pain and flank pain. The pain had begun suddenly 2 hours prior when she was reaching into a freezer to get a bag of frozen vegetables. She described the pain as sharp, constant, severe, and worse with movements and breathing. The pain radiated to the left shoulder. On review of systems, the patient had mild dyspnea and nausea. She denied fever, chills, headache, vision changes, vomiting, or urinary symptoms. Her medical history was notable for obstructive sleep apnea, gastroesophageal reflux disease, arthritis, fibromyalgia, depression, obesity, and idiopathic intracranial hypertension. For the latter, she had a VP (ventriculoperitoneal shunt placed 14 years prior to this visit. She had a history of 2 shunt revisions, the most recent 30 days before this ED visit. Significant findings: An immediate post-op abdominal x-ray performed after the patient’s VP shunt revision 30 days prior to this ED visit reveals the VP shunt tip in the mid abdomen. A CT of the abdomen performed on the day of the ED visit reveals the VP shunt tip interposed between the spleen and the diaphragm. Discussion: VP shunts have been reported to migrate to varied locations in the thorax and abdomen. Incidence of abdominal complications of VP shunt placement ranges from 10%-30%, and can include pseudocyst formation, migration, peritonitis, CSF ascites, infection, and viscus perforation. Incidence of distal shunt migration is reported as 10%, and most previously reported cases occurred in pediatric patients.1 A recent retrospective review cited BMI greater than thirty and previous shunt procedure as risk factors for distal shunt migration.2 The patient in the case presented had a BMI of 59 and 3 previous shunt procedures.

  4. Conservation physiology of animal migration

    Science.gov (United States)

    Lennox, Robert J.; Chapman, Jacqueline M.; Souliere, Christopher M.; Tudorache, Christian; Wikelski, Martin; Metcalfe, Julian D.; Cooke, Steven J.

    2016-01-01

    Migration is a widespread phenomenon among many taxa. This complex behaviour enables animals to exploit many temporally productive and spatially discrete habitats to accrue various fitness benefits (e.g. growth, reproduction, predator avoidance). Human activities and global environmental change represent potential threats to migrating animals (from individuals to species), and research is underway to understand mechanisms that control migration and how migration responds to modern challenges. Focusing on behavioural and physiological aspects of migration can help to provide better understanding, management and conservation of migratory populations. Here, we highlight different physiological, behavioural and biomechanical aspects of animal migration that will help us to understand how migratory animals interact with current and future anthropogenic threats. We are in the early stages of a changing planet, and our understanding of how physiology is linked to the persistence of migratory animals is still developing; therefore, we regard the following questions as being central to the conservation physiology of animal migrations. Will climate change influence the energetic costs of migration? Will shifting temperatures change the annual clocks of migrating animals? Will anthropogenic influences have an effect on orientation during migration? Will increased anthropogenic alteration of migration stopover sites/migration corridors affect the stress physiology of migrating animals? Can physiological knowledge be used to identify strategies for facilitating the movement of animals? Our synthesis reveals that given the inherent challenges of migration, additional stressors derived from altered environments (e.g. climate change, physical habitat alteration, light pollution) or interaction with human infrastructure (e.g. wind or hydrokinetic turbines, dams) or activities (e.g. fisheries) could lead to long-term changes to migratory phenotypes. However, uncertainty remains

  5. Many Faces of Migrations

    Directory of Open Access Journals (Sweden)

    Milica Antić Gaber

    2013-12-01

    We believe that in the present thematic issue we have succeeded in capturing an important part of the modern European research dynamic in the field of migration. In addition to well-known scholars in this field several young authors at the beginning their research careers have been shortlisted for the publication. We are glad of their success as it bodes a vibrancy of this research area in the future. At the same time, we were pleased to receive responses to the invitation from representatives of so many disciplines, and that the number of papers received significantly exceeded the maximum volume of the journal. Recognising and understanding of the many faces of migration are important steps towards the comprehensive knowledge needed to successfully meet the challenges of migration issues today and even more so in the future. It is therefore of utmost importance that researchers find ways of transferring their academic knowledge into practice – to all levels of education, the media, the wider public and, of course, the decision makers in local, national and international institutions. The call also applies to all authors in this issue of the journal.

  6. Collisionless damping of nonlinear dust ion acoustic wave due to dust charge fluctuation

    International Nuclear Information System (INIS)

    Ghosh, Samiran; Chaudhuri, Tushar K.; Sarkar, Susmita; Khan, Manoranjan; Gupta, M.R.

    2002-01-01

    A dissipation mechanism for the damping of the nonlinear dust ion acoustic wave in a collisionless dusty plasma consisting of nonthermal electrons, ions, and variable charge dust grains has been investigated. It is shown that the collisionless damping due to dust charge fluctuation causes the nonlinear dust ion acoustic wave propagation to be described by the damped Korteweg-de Vries equation. Due to the presence of nonthermal electrons, the dust ion acoustic wave admits both positive and negative potential and it suffers less damping than the dust acoustic wave, which admits only negative potential

  7. Respiratory effects of borax dust.

    Science.gov (United States)

    Garabrant, D H; Bernstein, L; Peters, J M; Smith, T J; Wright, W E

    1985-12-01

    The relation of respiratory symptoms, pulmonary function, and abnormalities of chest radiographs to estimated exposures of borax dust has been investigated in a cross sectional study of 629 actively employed borax workers. Ninety three per cent of the eligible workers participated in the study and exposures ranged from 1.1 mg/m3 to 14.6 mg/m3. Symptoms of acute respiratory irritation such as dryness of the mouth, nose, or throat, dry cough, nose bleeds, sore throat, productive cough, shortness of breath, and chest tightness were related to exposures of 4.0 mg/m3 or more, and were infrequent at exposures of 1.1 mg/m3. Symptoms of persistent respiratory irritation meeting the definition of chronic simple bronchitis were related to exposure among non-smokers. Decrements in the FEV1 as a percentage of predicted were seen among smokers who had heavy cumulative borax exposures (greater than or equal to 80 mg/m3 years) but were not seen among less exposed smokers or among non-smokers. Radiographic abnormalities were uncommon and were not related to dust exposure. Borax dust appears to act as a simple respiratory irritant and perhaps causes small changes in the FEV1 among smokers who are heavily exposed.

  8. Dust-Tolerant Intelligent Electrical Connection System

    Science.gov (United States)

    Lewis, Mark; Dokos, Adam; Perotti, Jose; Calle, Carlos; Mueller, Robert; Bastin, Gary; Carlson, Jeffrey; Townsend, Ivan, III; Immer, Chirstopher; Medelius, Pedro

    2012-01-01

    Faults in wiring systems are a serious concern for the aerospace and aeronautic (commercial, military, and civilian) industries. Circuit failures and vehicle accidents have occurred and have been attributed to faulty wiring created by open and/or short circuits. Often, such circuit failures occur due to vibration during vehicle launch or operation. Therefore, developing non-intrusive fault-tolerant techniques is necessary to detect circuit faults and automatically route signals through alternate recovery paths while the vehicle or lunar surface systems equipment is in operation. Electrical connector concepts combining dust mitigation strategies and cable diagnostic technologies have significant application for lunar and Martian surface systems, as well as for dusty terrestrial applications. The dust-tolerant intelligent electrical connection system has several novel concepts and unique features. It combines intelligent cable diagnostics (health monitoring) and automatic circuit routing capabilities into a dust-tolerant electrical umbilical. It retrofits a clamshell protective dust cover to an existing connector for reduced gravity operation, and features a universal connector housing with three styles of dust protection: inverted cap, rotating cap, and clamshell. It uses a self-healing membrane as a dust barrier for electrical connectors where required, while also combining lotus leaf technology for applications where a dust-resistant coating providing low surface tension is needed to mitigate Van der Waals forces, thereby disallowing dust particle adhesion to connector surfaces. It also permits using a ruggedized iris mechanism with an embedded electrodynamic dust shield as a dust barrier for electrical connectors where required.

  9. Ocular toxicity of authentic lunar dust.

    Science.gov (United States)

    Meyers, Valerie E; Garcìa, Hector D; Monds, Kathryn; Cooper, Bonnie L; James, John T

    2012-07-20

    Dust exposure is a well-known occupational hazard for terrestrial workers and astronauts alike and will continue to be a concern as humankind pursues exploration and habitation of objects beyond Earth. Humankind's limited exploration experience with the Apollo Program indicates that exposure to dust will be unavoidable. Therefore, NASA must assess potential toxicity and recommend appropriate mitigation measures to ensure that explorers are adequately protected. Visual acuity is critical during exploration activities and operations aboard spacecraft. Therefore, the present research was performed to ascertain the ocular toxicity of authentic lunar dust. Small (mean particle diameter = 2.9 ± 1.0 μm), reactive lunar dust particles were produced by grinding bulk dust under ultrapure nitrogen conditions. Chemical reactivity and cytotoxicity testing were performed using the commercially available EpiOcularTM assay. Subsequent in vivo Draize testing utilized a larger size fraction of unground lunar dust that is more relevant to ocular exposures (particles lunar dust was minimally irritating. Minor irritation of the upper eyelids was noted at the 1-hour observation point, but these effects resolved within 24 hours. In addition, no corneal scratching was observed using fluorescein stain. Low-titanium mare lunar dust is minimally irritating to the eyes and is considered a nuisance dust for ocular exposure. No special precautions are recommended to protect against ocular exposures, but fully shielded goggles may be used if dust becomes a nuisance.

  10. Migration Process Evolution in Europe

    Directory of Open Access Journals (Sweden)

    Carmen Tudorache

    2006-08-01

    Full Text Available The migration phenomenon has always existed, fluctuating by the historic context, the economic, political, social and demographic disparities between the Central and East European countries and the EU Member States, the interdependencies between the origin and receiving countries and the European integration process evolutions. In the European Union, an integrated and inclusive approach of the migration issue is necessary. But a common policy on migration rests an ambitious objective. A common approach of the economic migration management and the harmonization of the migration policies of the Member States represented a challenge for the European Union and will become urgent in the future, especially due to the demographic ageing.

  11. Migrations in Slovenian geography textbooks

    Directory of Open Access Journals (Sweden)

    Jurij Senegačnik

    2013-12-01

    Full Text Available In Slovenia, the migrations are treated in almost all geographical textbooks for different levels of education. In the textbooks for the elementary school from the sixth to ninth grade, students acquire knowledge of the migrations by the inductive approach. Difficulty level of treatment and quantity of information are increasing by the age level. In the grammar school program a trail of gaining knowledge on migration is deductive. Most attention is dedicated to migrations in general geography textbooks. The textbooks for vocational and technical school programs deal with migrations to a lesser extent and with different approaches.

  12. Dust characterisation for hot gas filters

    Energy Technology Data Exchange (ETDEWEB)

    Dockter, B.; Erickson, T.; Henderson, A.; Hurley, J.; Kuehnel, V.; Katrinak, K.; Nowok, J.; O`Keefe, C.; O`Leary, E.; Swanson, M.; Watne, T. [University of North Dakota, Grand Forks, ND (United States). Energy and Environmental Research Center (UNDEERC)

    1998-03-01

    Hot gas filtration to remove particulates from the gas flow upstream of the gas turbine is critical to the development of many of the advanced coal-fired power generation technologies such as the Air Blown Gasification Cycle (ABGC), a hybrid gasification combined cycle being developed in the UK. Ceramic candle filters are considered the most promising technology for this purpose. Problems of mechanical failure and of `difficult-to-clean` dusts causing high pressure losses across the filter elements need to be solved. The project investigated the behaviour of high-temperature filter dusts, and the factors determining the ease with which they can be removed from filters. The high-temperature behaviour of dusts from both combustion and gasification systems was investigated. Dust samples were obtained from full-scale demonstration and pilot-scale plant operating around the world. Dust samples were also produced from a variety of coals, and under several different operating conditions, on UNDEERC`s pilot-scale reactor. Key factors affecting dust behaviour were examined, including: the rates of tensile strength developing in dust cakes; the thermochemical equilibria pertaining under filtration conditions; dust adhesivity on representative filter materials; and the build-up and cleaning behaviour of dusts on representative filter candles. The results obtained confirmed the importance of dust temperature, dust cake porosity, cake liquid content, and particle size distribution in determining the strength of a dust cake. An algorithm was developed to indicate the likely sticking propensity of dusts as a function of coal and sorbent composition and combustion conditions. This algorithm was incorporated into a computer package which can be used to judge the degree of difficulty in filter cleaning that can be expected to arise in a real plant based on operating parameters and coal analyzes. 6 figs.

  13. Comet Dust: The Story of Planet Formation as Told by the Tiniest of Particles

    Science.gov (United States)

    Wooden, D. H.

    2005-01-01

    Our planetary system formed out of a gas-rich disk-shaped nebula with the early Sun at its center. Many small icy bodies were consumed by the formation of the giant planets. However, many km-size icy bodies were tossed out of the giant-planet region to the cold, distant reaches of our solar system. Comets remained in their places of cold storage until perturbed into orbits that carry them into the inner solar system where they pass relatively close to the Sun. Comets are warmed by the Sun and shed material from their outer layers. The ices and gases shed by comets reveal simple and complex organic molecules were present at the time and in the region of the formation of the giant planets. Where the Earth was forming was too hot and had too intense sunlight for many of these ices and molecules to survive. The dust shed by comets tells us that some stardust survived unaltered but much of the dust was heated and crystallized before becoming part of the comet. Therefore, comet dust grains tell of large radial migrations from the cold outer reaches near Neptune into the hot regions near the forming Sun, and then back out to the cold regions where icy comets were accreting and forming. On 2005 July 4, the NASA Deep Impact Mission hit a comet and ejected primitive materials fiom its interior. These materials were not released into the comet s coma during normal activity. Despite the many passages of this comet close to the Sun, these primitive volatile gases and dust grains survived in its interior. Comet dust grains show that cold and hot materials were mixed into the same tiny particle very early in the formation of the solar system, and these aggregate dust grains never saw high temperatures again. The survival of primitive materials in comet nuclei suggests comets could have delivered organic molecules and primitive dust grains to early Earth.

  14. House dust in seven Danish offices

    Science.gov (United States)

    Mølhave, L.; Schneider, T.; Kjærgaard, S. K.; Larsen, L.; Norn, S.; Jørgensen, O.

    Floor dust from Danish offices was collected and analyzed. The dust was to be used in an exposure experiment. The dust was analyzed to show the composition of the dust which can be a source of airborne dust indoors. About 11 kg of dust from vacuum cleaner bags from seven Danish office buildings with about 1047 occupants (12 751 m 2) was processed according to a standardized procedure yielding 5.5 kg of processed bulk dust. The bulk dust contained 130.000-160.000 CFU g -1 microorganisms and 71.000-90.000 CFU g -1 microfungi. The content of culturable microfungi was 65-123 CFU 30 g -1 dust. The content of endotoxins ranged from 5.06-7.24 EU g -1 (1.45 ng g -1 to 1.01 ng g -1). Allergens (ng g -1) were from 147-159 (Mite), 395-746 (dog) and 103-330 (cat). The macro molecular organic compounds (the MOD-content) varied from 7.8-9.8 mg g -1. The threshold of release of histamine from basophil leukocytes provoked by the bulk dust was between 0.3 and 1.0 mg ml -1. The water content was 2% (WGT) and the organic fraction 33%. 6.5-5.9% (dry) was water soluble. The fiber content was less than 0.2-1.5% (WGT) and the desorbable VOCs was 176-319 μg g -1. Most of the VOC were aldehydes. However, softeners for plastic (DBP and DEHP) were present. The chemical composition includes human and animal skin fragments, paper fibers, glass wool, wood and textilefibers and inorganic and metal particles. The sizes ranged from 0.001-1 mm and the average specific density was 1.0 g m -3. The bulk dust was resuspended and injected into an exposure chamber. The airborne dust was sampled and analyzed to illustrate the exposures that can result from sedimented dirt and dust. The airborne dust resulting from the bulk dust reached concentrations ranging from 0.26-0.75 mg m -3 in average contained 300-170 CFU m -3. The organic fraction was from 55-70% and the water content about 2.5% (WGT). The content of the dust was compared to the similar results reported in the literature and its toxic potency is

  15. Constraints on the magnitude of the deglacial migration of the ITCZ in the Central Equatorial Pacific Ocean

    Science.gov (United States)

    Reimi, Maria A.; Marcantonio, Franco

    2016-11-01

    Accurate paleo-latitudinal reconstructions of the Intertropical Convergence Zone (ITCZ) are necessary for understanding tropical hydroclimate and atmospheric circulation. Paleoclimate models and records suggest that as global temperatures increase, the ITCZ should migrate towards the warmer hemisphere. Many uncertainties remain regarding the magnitude of this migration, and few studies have focused on the Central Equatorial Pacific (CEP). Here, we use eolian dust records recovered from three locations in the CEP to address changes in dust provenance across the paleo ITCZ since the last glacial maximum (LGM). Radiogenic isotope compositions of Nd and Pb show that dust delivered to the CEP was sourced mainly from two regions: East Asia and South America. From these data we deduced that since Marine Oxygen Isotope Stage 2 (MIS2) the ITCZ has migrated north to its modern position, being displaced by as much as 7°, to as little as 2.5°. We find that the ITCZ migrated further north during the early Holocene (∼9 kyr), reaching its position furthest north during the mid-Holocene warm interval (∼7 kyr), based on an increase in South American dust at the northernmost sites.

  16. Characterization of high concentration dust generator

    International Nuclear Information System (INIS)

    Shimura, Toichiro; Yokochi, Akira

    1999-01-01

    This paper describes the development of fluidized bed type high concentration dust generator that keeps for long period dust concentration range of about 10 mg/m 3 for the study of working place monitoring system and evaluation of respirator. The generator is keeping constant powder in fluidized bed for keeping the dust concentration. It is necessary to keep constant feeding rate of powder in order to keep the quantity of dust in the fluidized bed. Our generator enables to obtain constant feeding rate by a screw feeder and by using mixed powder with fluidising particles (glass beads) before feeding. The generator produces high concentration dust of 11.3 mg/m 3 ± 1.0 mg/m 3 for about 5 hours and keeps the dust size 4.2-4.6 μm in mass median aerodynamic diameter with reasonable reproducibility. (author)

  17. Molecules and dust in Cassiopeia A

    DEFF Research Database (Denmark)

    Biscaro, Chiara; Cherchneff, Isabelle

    2016-01-01

    We study the dust evolution in the supernova remnant Cassiopeia A. We follow the processing of dust grains that formed in the Type II-b supernova ejecta by modelling the sputtering of grains. The dust is located in dense ejecta clumps that are crossed by the reverse shock. We also investigate......-rich clumps that correspond to the outermost carbon-rich ejecta zone. We consider the various dust components that form in the supernova, several reverse shock velocities and inter-clump gas temperatures, and derive grain-size distributions and masses for the dust as a function of time. Both non...... and size, and the shock velocity in the clump. A Type II-b SN forms small grains that are sputtered within the clumps and in the inter-clump medium. For Cas A, silicate grains do not survive thermal sputtering in the inter-clump medium, while alumina, silicon carbide, and carbon dust may survive...

  18. Active Dust Experiment in the Mesosphere

    International Nuclear Information System (INIS)

    Norberg, Carol; Pellinen-Wannberg, Asta

    2008-01-01

    The mesosphere stretches from an altitude of about 50 to 90 km above the Earth's surface. Meteors entering the Earth's atmosphere are believed to ablate and hence give rise to a thin layer of dust particles in the upper part of the Earth's mesosphere. It seems that the dust is most dense in a layer that lies between 80 and 90 km. The dust particles are thought to have sizes of a few to tens of nanometers. Efforts have been made to measure these particles using rockets and radar techniques with limited success. We propose to release dust into the mesosphere over northern Sweden at a height of about 90 km and observe the released dust using the EISCAT radar system. The dust will be launched from the Swedish Space Corporation Esrange Space Centre on a single-stage Improved-Orion rocket that will be launched so that its flight path will be in the radar field of view.

  19. Dust observations by PFS on Mars Express

    Science.gov (United States)

    Zasova, L. V.; Formisano, V.; Moroz, V. I.; Grassi, D.; Ignatiev, N. I.; Blecka, M. I.; Maturilli, A.; Palomba, E.; Piccioni, G.; Pfs Team

    Dust is always present in the Martian atmosphere with opacity, which changes from values below 0.1 (at 9 μ m) up to several units during the dust storms. From the thermal IR (LW channel of PFS) the dust opacity is retrieved in a self consistent way together with the temperature profile from the same spectrum A preliminary investigation along the orbit, which comes through Hellas, shows that the value of dust opacity anticorrelates with surface altitude. From -70 to +25 of latitude the vertical dust distribution follows the exponential low with the scale of 12 km, which corresponds to the gaseous scale height near noon and indicates for well mixed condition. The dust opacity, corresponding to the zero surface altitude, is found of 0.25+-0.05. More detailed investigations of all available data will be presented, including analysis of both short- and long- wavelength spectra of PFS.

  20. Formation and dissociation of dust molecules in dusty plasma

    International Nuclear Information System (INIS)

    Yan Jia; Feng Fan; Liu Fucheng; Dong Lifang; He Yafeng

    2016-01-01

    Dust molecules are observed in a dusty plasma experiment. By using measurements with high spatial resolution, the formation and dissociation of the dust molecules are studied. The ion cloud in the wake of an upper dust grain attracts the lower dust grain nearby. When the interparticle distance between the upper dust grain and the lower one is less than a critical value, the two dust grains would form a dust molecule. The upper dust grain always leads the lower one as they travel. When the interparticle distance between them is larger than the critical value, the dust molecule would dissociate. (paper)

  1. Trace metals in urban road dust

    International Nuclear Information System (INIS)

    Randazzo, Loredana Antonella; Dongarra, Gaetano; Manno, Emanuela; Varrica, Daniela

    2006-01-01

    Heavy metals associated with urban road dust is a matter for concern as they may have serious effects on biological systems. The bioavailability and potential toxicity of metals bound to urban dust is related to the specific chemical form of the element. In the present article are reported the determinations and chemical speciation of As, Ba, Cr, Cu, Mo, Ni, Pb and Zn in six samples of road dust collected within the urban centre and the outskirts of Palermo [it

  2. Cylindrical dust acoustic waves with transverse perturbation

    International Nuclear Information System (INIS)

    Xue Jukui

    2003-01-01

    The nonlinear dust acoustic waves in dusty plasmas with the combined effects of bounded cylindrical geometry and the transverse perturbation are studied. Using the perturbation method, a cylindrical Kadomtsev-Petviashvili (CKP) equation that describes the dust acoustic waves is deduced for the first time. A particular solution of this CKP equation is also obtained. It is shown that the dust acoustic solitary waves can exist in the CKP equation

  3. The control and prevention of dust explosions

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    Papers presented discussed: explosion characteristics and hybrid mixtures explosion characteristics and influencing factors, propagation of dust explosions in ducts, prevention of dust explosions, desensitization, explosion-proof type of construction, explosion pressure relief, optical flame barriers, slide-valves for explosion protection, Ventex explosion barrier valves, grinding and mixing plants, spray driers, dust explosions in silos, and explosion-proof bucket elevators. One paper has been abstracted separately.

  4. Japanese migration in contemporary Japan: economic segmentation and interprefectural migration.

    Science.gov (United States)

    Fukurai, H

    1991-01-01

    This paper examines the economic segmentation model in explaining 1985-86 Japanese interregional migration. The analysis takes advantage of statistical graphic techniques to illustrate the following substantive issues of interregional migration: (1) to examine whether economic segmentation significantly influences Japanese regional migration and (2) to explain socioeconomic characteristics of prefectures for both in- and out-migration. Analytic techniques include a latent structural equation (LISREL) methodology and statistical residual mapping. The residual dispersion patterns, for instance, suggest the extent to which socioeconomic and geopolitical variables explain migration differences by showing unique clusters of unexplained residuals. The analysis further points out that extraneous factors such as high residential land values, significant commuting populations, and regional-specific cultures and traditions need to be incorporated in the economic segmentation model in order to assess the extent of the model's reliability in explaining the pattern of interprefectural migration.

  5. Labour migration from Turkey.

    Science.gov (United States)

    Uner, S

    1988-01-01

    This study is concerned with Turkish labor migration to Western Europe. Earlier and recent patterns of labor migration, characteristics of migrants by occupation, area of destination, and by geographical origins are discussed. Economic and demographic consequences of labor migration are also analyzed. It is estimated that Turkey's population will reach 73 million at the year 2000 with the present growth rate of 2.48% annually. Considering the efforts made to slow down the present high fertility rates and assuming that the decrease in labor force participation during 1970-1980 continues, the author concludes that the labor supply will increase with a growth rate of 2% annually for the next 13-15 years. Thus, the labor supply will reach 26.6 million people in the year 2000 from the 1980 level of 17.8 million. Assuming also that the income/employment elasticity of .25 which was observed throughout the period of 1960-1980 will not change until 2000, the annual growth rate of employment may be estimated as 1.5%. Thus, the number of people employed will reach 20 million in the year 1990 and 23.2 million in the year 2000. 8.8 million people will join the labor market as new entrants between 1980 and 2000. Only 6 million people out of 8.8 million will be employed. Thus, in the year 2000, it is estimated that 2.8 million new unemployed people will be added to the already open unemployment figure 1980 census data give the number of unemployed as .6 million people. Adding the 2.8 million new unemployed to this figure totals 3.4 million unemployed in 2000. The State Planning Organization's estimate of labor surplus for 1980 was 2.5 million people. When 2.8 million unemployed people are added to this figure, the labor surplus for the year 2000 reaches 5.3 million people.

  6. ILO - International Migration Programme.

    Science.gov (United States)

    Boudraa, Miriam

    2011-01-01

    In a wide International Context characterised not only by the economical development but also by the social, cultural, political and individual development, we witness more and more to a exchange between the developed and the developing countries, which can be translated especially in the migration of the work force. In theory, all countries are either countries of origin either countries of transit or destination, and they are all responsible for the rights of migrant workers by promoting the rights, by monitoring and by preventing the abusive conditions. The process of migration of the workforce can be divided into three stages: the first coincides with the period prior to departure, the second is represented by the aftermath of the departure and the period of stay in the country of destination, the third stage corresponds to the return in the country of origin. The workers must be protected throughout this process by the international organizations that perform the catalytic role of communication and exchange between countries, for the only purpose of protecting the rights of immigrant and/or immigrants workers. The responsibility for the protection of workers is divided among the various players in the International Labour Organisation. Every country has to apply measures according to the international standards regarding workers' rights, standards that guide the various countries in the formulation and implementation of their policies and legislation. These standards are suggested by International Conventions, the ILO Conventions and other international instruments such as the human rights instrument. There has been a big step forward once the ILO Fundamental Conventions and Conventions on Migrant Workers where implemented and this implementation represented the use of the Guidelines "ILO Multilateral Framework on Labour Migration".

  7. Dust control at Yucca Mountain project

    International Nuclear Information System (INIS)

    Kissell, F.; Jurani, R.; Dresel, R.; Reaux, C.

    1999-01-01

    This report describes actions taken to control silica dust at the Yucca Mountain Exploratory Studies Facility, a tunnel located in Southern Nevada that is part of a scientific program to determine site suitability for a potential nuclear waste repository. The rock is a volcanic tuff containing significant percentages of both quartz and cristobalite. Water use for dust control was limited because of scientific test requirements, and this limitation made dust control a difficult task. Results are reported for two drifts, called the Main Loop Drift and the Cross Drift. In the Main Loop Drift, dust surveys and tracer gas tests indicated that air leakage from the TBM head, the primary ventilation duct, and movement of the conveyor belt were all significant sources of dust. Conventional dust control approaches yielded no significant reductions in dust levels. A novel alternative was to install an air cleaning station on a rear deck of the TBM trailing gear. It filtered dust from the contaminated intake air and discharged clean air towards the front of the TBM. The practical effect was to produce dust levels below the exposure limit for all TBM locations except close to the head. In the Cross Drift, better ventilation and an extra set of dust seals on the TBM served to cut down the leakage of dust from the TBM cutter head. However, the conveyor belt was much dustier than the belt in the main loop drift. The problem originated with dirt on the bottom of the belt return side and much spillage from the belt top side. Achieving lower dust levels in hard rock tunneling operations will require new approaches as well as a more meticulous application of existing technology. Planning for dust control will require specific means to deal with dust that leaks from the TBM head, dust that originates with leaky ventilation systems, and dust that comes from conveyor belts. Also, the application of water could be more efficient if automatic controls were used to adjust the water flow

  8. Beryllium dust generation resulting from plasma bombardment

    International Nuclear Information System (INIS)

    Doerner, R.; Mays, C.

    1997-01-01

    The beryllium dust resulting from erosion of beryllium samples subjected to plasma bombardment has been measured in PISCES-B. Loose surface dust was found to be uniformly distributed throughout the device and accounts for 3% of the eroded material. A size distribution measurement of the loose surface dust shows an increasing number of particles with decreasing diameter. Beryllium coatings on surfaces with a line of sight view of the target interaction region account for an additional 33% of the eroded beryllium material. Flaking of these surface layers is observed and is thought to play a significant role in dust generation inside the vacuum vessel. (orig.)

  9. Control of dust production in ITER

    International Nuclear Information System (INIS)

    Rodriguez-Rodrigo, L.; Ciattaglia, S.; Elbez-Uzan, J.

    2006-01-01

    In the last years dust has been observed in a number of fusion devices and is being studied more in detail for understanding in particular the physical phenomena related to its formation, its composition, physical and chemical characteristics, and the amount of produced dust. The extrapolation of dust formation to ITER predicts (with large error bars), a large mass of dust production with a scattered size distribution. To evaluate the impact of dust on safety, assumptions have also been made on radionuclide inventory, and mobility in off-normal events, as well as any postulated contributions the dust may make to effluents or accidental releases. Solid activation products in structures are generally not readily mobilisable in incidental and accidental situations, so that activated dust, tritium and activated corrosions products are the important in-vessel source terms in postulated scenarios that assume a mobilisation and release of some fraction of this inventory. Such a release would require the simultaneous leak or bypass of several robust confinement barriers. Further concerns for dust may be the potential for chemical reactions between dust and coolant in the event of an in-vessel leak, and the theoretical possibility of a dust explosion, either of which could in principle cause a pressure rise that challenges one or more of the confinement barriers. Although these hazards can - and will - be controlled by other measures in the ITER design, application of the principle of Defence in Depth dictates that the dust inventory should also be minimised and controlled to prevent the potential hazard. A well-coordinated R-and-D programme is required to support this dust production control. This document provides from the safety point of view, an overview of existing data given in '' Dossier d'Options de Surete '', the first safety report presented in 2001 to the French Safety Authorities, and ITER documents; it also gathers information on status of studies on activated

  10. Urbanization, Migration, Information

    Directory of Open Access Journals (Sweden)

    Konstantin Lidin

    2016-05-01

    Full Text Available In the contemporary world urbanization becomes a large-scale process. Huge flows of people migrate from poorer districts to the cities with a higher level of consumption. It takes migrants about 15-25 years to give up their traditional ascetic way of life. In this period the ‘new citizens’ try to arrange compact settlements with an archaic way of life, insanitary conditions, high criminogenity and an authoritative local self-government. The processes of formation and decay of the ascetic enclave are viewed through the example of the ‘Shanghai’ trading neighborhood in Irkutsk.

  11. Neuronal Migration and Neuronal Migration Disorder in Cerebral Cortex

    OpenAIRE

    SUN, Xue-Zhi; TAKAHASHI, Sentaro; GUI, Chun; ZHANG, Rui; KOGA, Kazuo; NOUYE, Minoru; MURATA, Yoshiharu

    2002-01-01

    Neuronal cell migration is one of the most significant features during cortical development. After final mitosis, neurons migrate from the ventricular zone into the cortical plate, and then establish neuronal lamina and settle onto the outermost layer, forming an "inside-out" gradient of maturation. Neuronal migration is guided by radial glial fibers and also needs proper receptors, ligands, and other unknown extracellular factors, requests local signaling (e.g. some emitted by the Cajal-Retz...

  12. Integrative Analysis of Desert Dust Size and Abundance Suggests Less Dust Climate Cooling

    Science.gov (United States)

    Kok, Jasper F.; Ridley, David A.; Zhou, Qing; Miller, Ron L.; Zhao, Chun; Heald, Colette L.; Ward, Daniel S.; Albani, Samuel; Haustein, Karsten

    2017-01-01

    Desert dust aerosols affect Earths global energy balance through interactions with radiation, clouds, and ecosystems. But the magnitudes of these effects are so uncertain that it remains unclear whether atmospheric dust has a net warming or cooling effect on global climate. Consequently, it is still uncertain whether large changes in atmospheric dust loading over the past century have slowed or accelerated anthropogenic climate change, and the climate impact of possible future alterations in dust loading is similarly disputed. Here we use an integrative analysis of dust aerosol sizes and abundance to constrain the climatic impact of dust through direct interactions with radiation. Using a combination of observational, experimental, and model data, we find that atmospheric dust is substantially coarser than represented in current climate models. Since coarse dust warms global climate, the dust direct radiative effect (DRE) is likely less cooling than the 0.4 W m superscript 2 estimated by models in a current ensemble. We constrain the dust DRE to -0.20 (-0.48 to +0.20) W m superscript 2, which suggests that the dust DRE produces only about half the cooling that current models estimate, and raises the possibility that dust DRE is actually net warming the planet.

  13. Carbohydrate and protein contents of grain dusts in relation to dust morphology.

    Science.gov (United States)

    Dashek, W V; Olenchock, S A; Mayfield, J E; Wirtz, G H; Wolz, D E; Young, C A

    1986-01-01

    Grain dusts contain a variety of materials which are potentially hazardous to the health of workers in the grain industry. Because the characterization of grain dusts is incomplete, we are defining the botanical, chemical, and microbial contents of several grain dusts collected from grain elevators in the Duluth-Superior regions of the U.S. Here, we report certain of the carbohydrate and protein contents of dusts in relation to dust morphology. Examination of the gross morphologies of the dusts revealed that, except for corn, each dust contained either husk or pericarp (seed coat in the case of flax) fragments in addition to respirable particles. When viewed with the light microscope, the fragments appeared as elongated, pointed structures. The possibility that certain of the fragments within corn, settled, and spring wheat were derived from cell walls was suggested by the detection of pentoses following colorimetric assay of neutralized 2 N trifluoroacetic acid hydrolyzates of these dusts. The presence of pentoses together with the occurrence of proteins within water washings of grain dusts suggests that glycoproteins may be present within the dusts. With scanning electron microscopy, each dust was found to consist of a distinct assortment of particles in addition to respirable particles. Small husk fragments and "trichome-like" objects were common to all but corn dust. Images FIGURE 4. FIGURE 5. PMID:3709476

  14. Network migration for printers

    CERN Multimedia

    2016-01-01

    Further to the recent General Purpose (office) Network reorganisation (as announced in the Bulletin - see here), please note that the majority of print devices will be automatically migrated to the new network IP address range on Tuesday 27 September.   This change should be transparent for these devices and therefore end-users, provided you have installed the printers from the Print Service website. A small number of devices will require manual intervention from the Printer Support team in order to migrate correctly. These devices will not change their IP address until the manual intervention, which will be carried out before Monday 3rd October. However, if you have mistakenly connected directly to the printer’s IP address, then your printing will be affected – please uninstall the printer (for help, see: KB3785), and re-install it from the Print Service website (or follow instructions for visitor machines). Please do this as soon as possible in order to avoid printing issues, t...

  15. Beyond the Melting Pot and Salad Bowl Views of Cultural Diversity: Advancing Cultural Diversity Education of Nutrition Educators.

    Science.gov (United States)

    Setiloane, Kelebogile Tsametse

    2016-10-01

    This article outlines how the melting pot and salad bowl views of cultural diversity have influenced the cultural training of nutrition educators and other health professionals. It explores how these views are changing in reaction to the changing demographics and health disparities seen in the US today and how the cultural training of nutrition educators has not kept up with these changing views. Suggestions for how this cultural education could be modified include placing a greater emphasis on both the cultural self-awareness of nutrition educators and the sociopolitical historical factors that influence the cultural orientation of nutrition educators and their clients. Copyright © 2016 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  16. MIGRATION AND ITS ENVIROMENTAL EFFECTS

    OpenAIRE

    Rashid SAEED; Rana NADIR IDREES; Humna IJAZ; Marriam FURQANI; Raziya NADEEM

    2012-01-01

    Migration can be ongoing shifting of a particular person from one location to another. The reason of shifting depends on selected thought deficiency, shock, difficulties, hopes, enthusiasm. Case study ended up recognizing the extent to which in turn migration can be relying on the specifics especially natural environment. This particular document expects to research the actual linkages between the atmosphere as well as migration using secondary data. Lots of investigation may be completed wit...

  17. Nordic Migration and Integration Research

    OpenAIRE

    Pyrhönen, Niko; Martikainen, Tuomas; Leinonen, Johanna

    2017-01-01

    EXECUTIVE SUMMARY Migration and integration are currently highly contentious topics in political, public and scientific arenas, and will remain so in the near future. However, many common migration-related prejudices and inefficien¬cies in the integration of the migrant population are due to the lack of sound, tested and accessible scientific research. Therefore, the study of migration – by developing basic research and by properly resourcing novel methodological approaches and interventions ...

  18. The challenges of managing migration

    Energy Technology Data Exchange (ETDEWEB)

    Tacoli, Cecilia

    2005-10-15

    Migration and urbanisation are driven by economic growth and social change, but also by deepening inequalities. Managing migration should not be equated with curbing it, as this inevitably reduces migrants' rights. But managing population movement whilst respecting the rights of migrants and nonmigrants, supporting the contribution of migration to poverty reduction and economic growth in sending and receiving areas and reducing the human and material costs of movement means that fundamental challenges need to be addressed.

  19. The Electric Environment of Martian Dust Devils

    Science.gov (United States)

    Barth, E. L.; Farrell, W. M.; Rafkin, S. C.

    2017-12-01

    While Martian dust devils have been monitored through decades of observations, we have yet to study their possible electrical effects from in situ instrumentation. However, evidence for the existence of active electrodynamic processes on Mars is provided by laboratory studies of analog material and field campaigns of dust devils on Earth. We have enabled our Mars regional scale atmospheric model (MRAMS) to estimate an upper limit on electric fields generated through dust devil circulations by including charged particles as defined from the Macroscopic Triboelectric Simulation (MTS) code. MRAMS is used to investigate the complex physics of regional, mesoscale, and microscale atmospheric phenomena on Mars; it is a 3-D, nonhydrostatic model, which permits the simulation of atmospheric flows with large vertical accelerations, such as dust devils. MTS is a 3-D particle code which quantifies charging associated with swirling, mixing dust grains; grains of pre-defined sizes and compositions are placed in a simulation box and allowed to move under the influence of winds and gravity. Our MRAMS grid cell size makes our results most applicable to dust devils of a few hundred meters in diameter. We have run a number of simulations to understand the sensitivity of the electric field strength to the particle size and abundance and the amount of charge on each dust grain. We find that Efields can indeed develop in Martian dust convective features via dust grain filtration effects. The overall value of these E-fields is strongly dependent upon dust grain size, dust load, and lifting efficiency, and field strengths can range from 100s of mV/m to 10s of kV/m.

  20. An experimental investigation on the influence of piston bowl geometry on RCCI performance and emissions in a heavy-duty engine

    International Nuclear Information System (INIS)

    Benajes, Jesús; Pastor, José V.; García, Antonio; Monsalve-Serrano, Javier

    2015-01-01

    Highlights: • Great influence of piston geometry at low load using single injection strategies. • Enhanced combustion development at mid load through optimized piston surface area. • Double injection allows ultra-low NOx and soot levels for the three piston geometries. • Unacceptable soot emissions at high load using single injection and bathtub geometry. • Stepped geometry leads to ultra-clean combustion with lower fuel consumption than CDC. - Abstract: This experimental work investigates the effects of piston bowl geometry on RCCI performance and emissions at low, medium and high engine loads. For this purpose three different piston bowl geometries with compression ratio 14.4:1 have been evaluated using single and double injection strategies. The experiments were conducted in a heavy-duty single-cylinder engine adapted for dual fuel operation. All the tests were carried out at 1200 rev/min. Results suggest that piston geometry has great impact on combustion development at low load conditions, more so when single injection strategies are used. It terms of emissions, it was proved that the three geometries enables ultra-low NOx and soot emissions at low and medium load when using double injection strategies. By contrast, unacceptable emissions were measured at high load taking into account EURO VI limitations. Finally, the application of a mathematical function considering certain self-imposed constraints suggested that the more suitable piston geometry for RCCI operation is the stepped one, which has a modified transition from the center to the squish region and reduced piston surface area than the stock geometry

  1. Modeling the Transport and Radiative Forcing of Taklimakan Dust over the Tibetan Plateau: A case study in the summer of 2006

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Siyu; Huang, J.; Zhao, Chun; Qian, Yun; Leung, Lai-Yung R.; Yang, Ben

    2013-01-30

    The Weather Research and Forecasting model with chemistry (WRF-Chem) is used to investigate an intense dust storm event during 26 to 30 July 2006 that originated over the Taklimakan Desert (TD) and transported to the northern slope of Tibetan Plateau (TP). The dust storm is initiated by the approach of a strong cold frontal system over the TD. In summer, the meridional transport of TD dust to the TP is favored by the thermal effect of the TP and the weakening of the East Asian westerly winds. During this dust storm, the transport of TD dust over the TP is further enhanced by the passage of the cold front. As a result, TD dust breaks through the planetary boundary layer and extends to the upper troposphere over the northern TP. TD dust flux arrived at the TP with a value of 6.6 Gg/day in this 5 day event but decays quickly during the southward migration over the TP due to dry deposition. The simulations show that TD dust cools the atmosphere near the surface and heats the atmosphere above with a maximum heating rate of 0.11 K day-1 at ~7 km over the TP. The event-averaged net radiative forcings of TD dust over the TP are -3.97, 1.61, and -5.58 Wm-2 at the top of the atmosphere (TOA), in the atmosphere, and at the surface, respectively. The promising performance of WRF-Chem in simulating dust and its radiative forcing provides confidence for use in further investigation of climatic impact of TD dust over the TP.

  2. The dust acoustic wave in a bounded dusty plasma with strong electrostatic interactions between dust grains

    International Nuclear Information System (INIS)

    Shukla, Nitin; Shukla, P.K.

    2011-01-01

    The dispersion relation for the dust acoustic wave (DAW) in an unmagnetized dusty plasma cylindrical waveguide is derived, accounting for strong electrostatic interactions between charged dust grains. It is found that the boundary effect limits the radial extent of the DAW. The present result should be helpful for understanding the frequency spectrum of the DAW in a dusty plasma waveguide with strongly coupled charged dust grains. - Highlights: → We study the dust acoustic wave (DAW) in a bounded plasma. → We account for interactions between dust grains. → The boundary effect limits the radial extent of the DAW.

  3. Radioactive dust in the air

    Energy Technology Data Exchange (ETDEWEB)

    Yano, N

    1956-01-01

    An electric precipitator is used to collect dust in the air because its collection efficiency for radioactive substances is up to 10 times that of the impactor of filter-paper types. About 10 cu m of air is filtered during 5 hours, and the trapped dust is measured more than 24 hours after collection to avoid the influence of naturally active substances. The average radioactivity of the air is approximately 10/sup -16/ c/cc. During the period of observation 4 peaks occurred. The dates and maximum levels of artificial activity, respectively, are November 4 to 10, 1954, 1.2 x 10/sup -7/ uc/l; April 11 to 13, 1955, 4.3 x 10/sup -8/ uc/l; November 25 to 28, 1955, maximum unknown; and March 22 to 25, 1956, 1.- x 10/sup -7/ uc/l. The presumed dates and places of detonation corresponding to the peaks are October 31, 1954 northwest of Japan; March 29, 1955, Nevada, US; November 22, 1955, near L. Baikal, USSR; and March 13 to 15, 1956 unknown.

  4. Comet Dust After Deep Impact

    Science.gov (United States)

    Wooden, Diane H.; Harker, David E.; Woodward, Charles E.

    2006-01-01

    When the Deep Impact Mission hit Jupiter Family comet 9P/Tempel 1, an ejecta crater was formed and an pocket of volatile gases and ices from 10-30 m below the surface was exposed (A Hearn et aI. 2005). This resulted in a gas geyser that persisted for a few hours (Sugita et al, 2005). The gas geyser pushed dust grains into the coma (Sugita et a1. 2005), as well as ice grains (Schulz et al. 2006). The smaller of the dust grains were submicron in radii (0-25.3 micron), and were primarily composed of highly refractory minerals including amorphous (non-graphitic) carbon, and silicate minerals including amorphous (disordered) olivine (Fe,Mg)2SiO4 and pyroxene (Fe,Mg)SiO3 and crystalline Mg-rich olivine. The smaller grains moved faster, as expected from the size-dependent velocity law produced by gas-drag on grains. The mineralogy evolved with time: progressively larger grains persisted in the near nuclear region, having been imparted with slower velocities, and the mineralogies of these larger grains appeared simpler and without crystals. The smaller 0.2-0.3 micron grains reached the coma in about 1.5 hours (1 arc sec = 740 km), were more diverse in mineralogy than the larger grains and contained crystals, and appeared to travel through the coma together. No smaller grains appeared at larger coma distances later (with slower velocities), implying that if grain fragmentation occurred, it happened within the gas acceleration zone. These results of the high spatial resolution spectroscopy (GEMINI+Michelle: Harker et 4. 2005, 2006; Subaru+COMICS: Sugita et al. 2005) revealed that the grains released from the interior were different from the nominally active areas of this comet by their: (a) crystalline content, (b) smaller size, (c) more diverse mineralogy. The temporal changes in the spectra, recorded by GEMIM+Michelle every 7 minutes, indicated that the dust mineralogy is inhomogeneous and, unexpectedly, the portion of the size distribution dominated by smaller grains has

  5. Countering inbreeding with migration 1. Migration from unrelated ...

    African Journals Online (AJOL)

    Ret:ieved 6 Octoher 1991; ut:cepted I8 Mur- 1995. The eff'ect of migration on inbreeding is moclelled fbr small populations with immigrants from a large unrelated population. Different migration rates and numbers fbr the two sexes are assumed, and a general recursion equation for inbreeding progress derived, which can ...

  6. The management of house dust mite allergies

    NARCIS (Netherlands)

    Bronswijk, van J.E.M.H.; Schober, G.; Kniest, F.M.

    1990-01-01

    A safe and practical home sanitation procedure for the removal of house dust mites (Dermatophagoides pteronyssinus) and their allergens is described. The severity of mite infestation was assessed with the use of the Acarex test, which measures the concentration of guanine in house dust, and all

  7. A rotating dust cloud in general relativity

    International Nuclear Information System (INIS)

    Bonnor, W.B.

    1977-01-01

    An axially symmetric, stationary exact solution of Einstein's equations for dust is studied. It is asymptotically flat, and represents a rotating dust cloud extending tenuously to infinity, containing a singularity at the centre. An explanation is given as to why there exists no corresponding solution in Newtonian theory. (author)

  8. Dust coagulation in protoplanetary disks : porosity matters

    NARCIS (Netherlands)

    Ormel, C. W.; Spaans, M.; Tielens, A. G. G. M.

    Context. Sticking of colliding dust particles through van der Waals forces is the first stage in the grain growth process in protoplanetary disks, eventually leading to the formation of comets, asteroids and planets. A key aspect of the collisional evolution is the coupling between dust and gas

  9. Correlation between Yellow Dust and Radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    AIZaabia, Mouza A [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Byoung-Jik [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    In East Asia, yellow dust or Asian Dust (AD) outbreaks are among the largest contributors of wind-blown dust that carry natural and anthropogenic radionuclides and subsequently alter their concentration and distribution throughout the environment. Although the Korean Peninsula has been experiencing AD events since ancient times, the research has tended to focus on the transport routes and characteristics of AD, rather than on its impact on radionuclide activity levels. This paper examines the relationship between radionuclide concentration in the air and the frequency of dusty days in South Korea during AD intrusion events. It also investigates whether increased radionuclide concentration is a function of either more mass or more dust contamination. In this study, significant linear correlations of gamma-emitting radionuclides were found with mass of dust and occurrence frequency of AD. Regardless of the source origin of the dust, {sup 137}Cs and {sup 7}Be concentration primarily depended on dust mass in the filter. Nonetheless, the correlations were greatly distorted in 2011 and in the spring season, particularly the correlations with AD days that were far below that of the correlations obtained for the whole study period. A possible explanation of these conflicting results is that a change in the dust source could appreciably alter the concentration, deposition, and distribution of airborne radionuclides.

  10. Correlation between Yellow Dust and Radioactivity

    International Nuclear Information System (INIS)

    AIZaabia, Mouza A; Kim, Byoung-Jik

    2015-01-01

    In East Asia, yellow dust or Asian Dust (AD) outbreaks are among the largest contributors of wind-blown dust that carry natural and anthropogenic radionuclides and subsequently alter their concentration and distribution throughout the environment. Although the Korean Peninsula has been experiencing AD events since ancient times, the research has tended to focus on the transport routes and characteristics of AD, rather than on its impact on radionuclide activity levels. This paper examines the relationship between radionuclide concentration in the air and the frequency of dusty days in South Korea during AD intrusion events. It also investigates whether increased radionuclide concentration is a function of either more mass or more dust contamination. In this study, significant linear correlations of gamma-emitting radionuclides were found with mass of dust and occurrence frequency of AD. Regardless of the source origin of the dust, 137 Cs and 7 Be concentration primarily depended on dust mass in the filter. Nonetheless, the correlations were greatly distorted in 2011 and in the spring season, particularly the correlations with AD days that were far below that of the correlations obtained for the whole study period. A possible explanation of these conflicting results is that a change in the dust source could appreciably alter the concentration, deposition, and distribution of airborne radionuclides

  11. Measurement of nicotine in household dust

    International Nuclear Information System (INIS)

    Kim, Sungroul; Aung, Ther; Berkeley, Emily; Diette, Gregory B.; Breysse, Patrick N.

    2008-01-01

    An analytical method of measuring nicotine in house dust was optimized and associations among three secondhand smoking exposure markers were evaluated, i.e., nicotine concentrations of both house dust and indoor air, and the self-reported number of cigarettes smoked daily in a household. We obtained seven house dust samples from self-reported nonsmoking homes and 30 samples from smoking homes along with the information on indoor air nicotine concentrations and the number of cigarettes smoked daily from an asthma cohort study conducted by the Johns Hopkins Center for Childhood Asthma in the Urban Environment. House dust nicotine was analyzed by isotope dilution gas chromatography-mass spectrometry (GC/MS). Using our optimized method, the median concentration of nicotine in the dust of self-reported nonsmoking homes was 11.7 ng/mg while that of smoking homes was 43.4 ng/mg. We found a substantially positive association (r=0.67, P<0.0001) between house dust nicotine concentrations and the numbers of cigarettes smoked daily. Optimized analytical methods showed a feasibility to detect nicotine in house dust. Our results indicated that the measurement of nicotine in house dust can be used potentially as a marker of longer term SHS exposure

  12. 30 CFR 56.9315 - Dust control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dust control. 56.9315 Section 56.9315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... control. Dust shall be controlled at muck piles, material transfer points, crushers, and on haulage roads...

  13. Role of dust in H II regions

    International Nuclear Information System (INIS)

    Sarazin, C.L.

    1975-01-01

    The purpose of this dissertation is to determine quantitatively the effects of U.V. absorbing dust on H II regions, and compare these effects with observations. Many observations indicate that dust grains are present within H II regions. An analytic theory is presented which describes all three of the effects of dust in H II regions. Although this model is relatively crude, it is useful in determining the approximate size of the modifications due to dust. In order to explore this problem more carefully, detailed numerical models of H II regions with dust were constructed. The ionization and thermal structure of these model H II regions is discussed. The observational consequences of the presence of dust are explored; the optical line intensities, radio continuum and line fluxes, and infrared emission of model H II regions with dust are given. These numerical models are compared with observations of diffuse nebulae. The optical line ratios are compared to several nearby bright H II regions, and it is found that the dust models may explain several anomalies in their spectrum

  14. The Continuous Monitoring of Desert Dust using an Infrared-based Dust Detection and Retrieval Method

    Science.gov (United States)

    Duda, David P.; Minnis, Patrick; Trepte, Qing; Sun-Mack, Sunny

    2006-01-01

    Airborne dust and sand are significant aerosol sources that can impact the atmospheric and surface radiation budgets. Because airborne dust affects visibility and air quality, it is desirable to monitor the location and concentrations of this aerosol for transportation and public health. Although aerosol retrievals have been derived for many years using visible and near-infrared reflectance measurements from satellites, the detection and quantification of dust from these channels is problematic over bright surfaces, or when dust concentrations are large. In addition, aerosol retrievals from polar orbiting satellites lack the ability to monitor the progression and sources of dust storms. As a complement to current aerosol dust retrieval algorithms, multi-spectral thermal infrared (8-12 micron) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Meteosat-8 Spinning Enhanced Visible and Infrared Imager (SEVIRI) are used in the development of a prototype dust detection method and dust property retrieval that can monitor the progress of Saharan dust fields continuously, both night and day. The dust detection method is incorporated into the processing of CERES (Clouds and the Earth s Radiant Energy System) aerosol retrievals to produce dust property retrievals. Both MODIS (from Terra and Aqua) and SEVERI data are used to develop the method.

  15. Thermal Tides During the 2001 Martian Global-Scale Dust Storm

    Science.gov (United States)

    Guzewich, Scott D.; Wilson, R. John; McConnochie, Timothy H.; Toigo, Anthony D.; Bandfield, Donald J.; Smith, Michael D.

    2014-01-01

    The 2001 (Mars Year 25) global dust storm radically altered the dynamics of the Martian atmosphere. Using observations from the Thermal Emission Spectrometer onboard the Mars Global Surveyor spacecraft and Mars WRF general circulation model simulations, we examine the changes to thermal tides and planetary waves caused by the storm. We find that the extratropical diurnal migrating tide is dramatically enhanced during the storm, particularly in the southern hemisphere, reaching amplitudes of more than 20 K. The tropical diurnal migrating tide is weakened to almost undetectable levels. The diurnal Kelvin waves are also significantly weakened, particularly during the period of global expansion at Ls=200deg-210deg. In contrast, the westward propagating diurnal wavenumber 2 tide strengthens to 4-8 K at altitudes above 30km. The wavenumber 1 stationary wave reaches amplitudes of 10-12 K at 50deg-70degN, far larger than is typically seen during this time of year. The phase of this stationary wave and the enhancement of the diurnal wavenumber 2 tide appear to be responses to the high-altitude westward propagating equatorial wavenumber 1 structure in dust mixing ratio observed during the storm in previous works. This work provides a global picture of dust storm wave dynamics that reveals the coupling between the tropics and high-latitude wave responses. We conclude that the zonal distribution of thermotidal forcing from atmospheric aerosol concentration is as important to understanding the atmospheric wave response as the total global mean aerosol optical depth.

  16. Dust plume formation in the free troposphere and aerosol size distribution during the Saharan Mineral Dust Experiment in North Africa

    KAUST Repository

    Khan, Basit Ali; Stenchikov, Georgiy L.; Weinzierl, Bernadett; Kalenderski, Stoitchko; Osipov, Sergey

    2015-01-01

    , this study combines model simulations and dust observations collected during the first stage of the Saharan Mineral Dust Experiment (SAMUM-I), which sampled dust events that extended from Morocco to Portugal, and investigated the spatial distribution

  17. Extracting lunar dust parameters from image charge signals produced by the Lunar Dust Experiment

    Science.gov (United States)

    Stanley, J.; Kempf, S.; Horanyi, M.; Szalay, J.

    2015-12-01

    The Lunar Dust Experiment (LDEX) onboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) is an impact ionization dust detector used to characterize the lunar dust exosphere generated by the impacts of large interplanetary particles and meteor streams (Horanyi et al., 2015). In addition to the mass and speed of these lofted particles, LDEX is sensitive to their charge. The resulting signatures of impact events therefore provide valuable information about not only the ambient plasma environment, but also the speed vectors of these dust grains. Here, impact events produced from LDEX's calibration at the Dust Accelerator Laboratory are analyzed using an image charge model derived from the electrostatic simulation program, Coulomb. We show that parameters such as dust grain speed, size, charge, and position of entry into LDEX can be recovered and applied to data collected during LADEE's seven-month mission.

  18. Migration and regional inequality

    DEFF Research Database (Denmark)

    Peng, Lianqing; Swider, Sarah

    2017-01-01

    Scholars studying economic inequality in China have maintained that regional inequality and economic divergence across provinces have steadily increased over the past 30 years. New studies have shown that this trend is a statistical aberration; calculations show that instead of quickly and sharply...... rising, regional inequality has actually decreased, and most recently, remained stable. Our study suggests that China’s unique migratory regime is crucial to understanding these findings. We conduct a counterfactual simulation to demonstrate how migration and remittances have mitigated income inequality...... across provinces in order to show that without these processes, we would have seen more of a rise in interprovincial income inequality. We conclude by arguing that inequality in China is still increasing, but it is changing and becoming less place-based. As regional inequality decreases, there are signs...

  19. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    habitats with those in rural habitats. Some species have decreased the frequency of migrants and migration distance in urban environments, and others have not. The other manuscript describes the small scale movements of three different Palaearctic migrants during winter in Africa in a farmland habitat....... In another species, environmental conditions are not a good predictor of movements, and possibly effects of timing constraints or food type play a role. Two manuscripts focus on the effects of human-induced habitat alterations on migratory behaviour. One compares the movements of partial migrants in urban...... and a forest reserve. In the degraded habitat all species used more space, although the consequence on bird density is less clear. Two manuscripts relate the migratory movements of a long-distance migrant with models of navigation. One compares model predictions obtained by simulation with actual movements...

  20. Making Migration Meaningful

    DEFF Research Database (Denmark)

    Benwell, Ann Fenger

    2013-01-01

    a way to escape family patriarchy and conformity, and can contribute to loss, hardship, and uncertainty for family members left behind. Further, mobility provides opportunities and a means to escape the stigma of ‘laziness’ culturally associated with poverty and immobility. Postsocialist separation has...... of absence by migrant family members, as both men and women are culturally permitted to be separate from their families. Migration is understood to contribute to prosperity, and separations contribute to generate growth and hishig (good fortune) for the good of the family. However, such mobility is also......Mongolia has experienced two decades since the demise of the Soviet Union and has implemented strategies to strengthen its economy and its democratic practices. Transitions from being a nomadic society to a Soviet satellite state and onwards to liberal democracy have greatly impacted family life...

  1. Nightly Test system migration

    CERN Document Server

    Win-Lime, Kevin

    2013-01-01

    The summer student program allows students to participate to the Cern adventure. They can follow several interesting lectures about particle science and participate to the experiment work. As a summer student, I had worked for LHCb experiment. LHCb uses a lot of software to analyze its data. All this software is organized in packages and projects. They are built and tested during the night using an automated system and the results are displayed on a web interface. Actually, LHCb is changing this system. It is looking for a replacement candidate. So I was charged to unify some internal interfaces to permit a swift migration. In this document, I will describe shortly the system used by LHCb, then I will explain what I have done in detail.

  2. Heating of Porous Icy Dust Aggregates

    Energy Technology Data Exchange (ETDEWEB)

    Sirono, Sin-iti [Earth and Environmental Sciences, Nagoya University, Tikusa-ku, Furo-cho, Nagoya 464-8601 (Japan)

    2017-06-10

    At the beginning of planetary formation, highly porous dust aggregates are formed through coagulation of dust grains. Outside the snowline, the main component of an aggregate is H{sub 2}O ice. Because H{sub 2}O ice is formed in amorphous form, its thermal conductivity is extremely small. Therefore, the thermal conductivity of an icy dust aggregate is low. There is a possibility of heating inside an aggregate owing to the decay of radionuclides. It is shown that the temperature increases substantially inside an aggregate, leading to crystallization of amorphous ice. During the crystallization, the temperature further increases sufficiently to continue sintering. The mechanical properties of icy dust aggregates change, and the collisional evolution of dust aggregates is affected by the sintering.

  3. The relaxation of plasmas with dust particles

    International Nuclear Information System (INIS)

    Chutov, Yu.I.; Kravchenko, A.Yu.; Schram, P.P.J.M.

    1997-01-01

    Various parameters of relaxing plasmas with dust particles including the electron and ion energy distributions function are numerically simulated at various parameters of the dust particles using the PIC method and taking into account the dynamics of the dust particle charge without the assumption about the equilibrium of electrons and ions. Coulomb collisions are taken into account in the framework of the method of stochastic differential equations. The relaxation of bounded plasma clouds expanding into a vacuum as well as the relaxation of a uniform plasma, in which dust particles appear at some initial time, are investigated. The obtained results show that the relaxation of plasmas can be accompanied by a deviation of the ion distribution function from equilibrium as well as a change of the mean energy of electrons and ions because of the dependence of the collection of electrons and ions by dust particles on their energy. (author)

  4. Recycling of steelmaking dusts: The Radust concept

    Directory of Open Access Journals (Sweden)

    Jalkanen H.

    2005-01-01

    Full Text Available Recycling of dusts and other wastes of steelmaking is becoming to a necessity of two reasons: due to high contents of iron oxides dusts are valuable raw material for steelmaking and tightening environmental legislation makes the landfill disposal of wastes more expensive. Fine dust fractions from various stages of steelmaking route contain besides iron and carbon heavy metals especially zinc and lead and heavy hydrocarbons that are acceptable neither for landfill disposal nor for recycling back to processes without any spe4cial treatments. Some theoretical and practical aspects concerning high temperature treatments of steelmaking dusts for removal of hazardous components and production of clean high iron raw material for recycling is discussed in this paper. The Radust technology developed at Koverhar steelwork in Finland for treatment of the most problematic fine fractions of blast furnace and oxygen converter dusts is shortly presented and discussed.

  5. Migration: the trends converge.

    Science.gov (United States)

    1985-09-01

    Formerly, Australia, New Zealand, Canada, and the US have served as permanent destinations for immigrants, while Europe's migrants have moved to more northerly countries to work for a time and then returned home. From 1973-1975 Europe's recruitment of foreign workers virtually ended, although family reunion for those immigrants allowed in was encouraged. Problems resulting from this new settlement migration include low paying jobs for immigrant women, high unemployment, and inadequate education for immigrant children. Illegal migrants from Latin America and the Caribbean enter the US and Canada each year while illegal North African immigrants enter Italy, Spain, and Greece. North America, Australia, and Europe have all received political refugees from Asia and Latin America. Increasingly, these foreigners compete in the labor market rather than simply fill jobs the native workers do not want. All the receiving countries have similar policy priorities: 1) more effective ways for controlling and monitoring inflows and checking illegal immigration; 2) encouraging normal living patterns and accepting refugees; and 3) integrating permanent migrants into the host country. Europe's public immigration encouragement prior to the first oil shock, has left some countries with a labor force that is reluctant to return home. It is unlikely that Europe will welcome foreign labor again in this decade, since unemployment among young people and women is high and family reunion programs may still bring in many immigrants. Less immigration pattern change will probably occur in North America, Australia, and New Zealand since these countries' populations are still growing and wages are more flexible. Immigration, regulated by policy, and emigration, determined by market forces, now are working in the same direction and will likely reduce future migration flows.

  6. Experimental and modeling researches of dust particles in the HL-2A tokamak

    Science.gov (United States)

    Huang, Zhi-Hui; Yan, Long-Wen; Tomita, Yukihiro; Feng, Zhen; Cheng, Jun; Hong, Wen-Yu; Pan, Yu-Dong; Yang, Qing-Wei; Duan, Xu-Ru

    2015-02-01

    The investigation of dust particle characteristics in fusion devices has become more and more imperative. In the HL-2A tokamak, the morphologies and compositions of dust particles are analyzed by using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX) with mapping. The results indicate that the sizes of dust particles are in a range from 1 μm to 1 mm. Surprisingly, stainless steel spheres with a diameter of 2.5 μm-30 μm are obtained. The production mechanisms of dust particles include flaking, disintegration, agglomeration, and arcing. In addition, dynamic characteristics of the flaking dust particles are observed by a CMOS fast framing camera and simulated by a computer program. Both of the results display that the ion friction force is dominant in the toroidal direction, while the centrifugal force is crucial in the radial direction. Therefore, the visible dust particles are accelerated toriodally by the ion friction force and migrated radially by the centrifugal force. The averaged velocity of the grain is on the order of ˜ 100 m/s. These results provide an additional supplement for one of critical plasma-wall interaction (PWI) issues in the framework of the International Thermonuclear Experimental Reactor (ITER) programme. Project supported by the National Magnetic Confinement Fusion Science Program of China (Grant Nos. 2014GB107000 and 2013GB112008), the National Natural Science Foundation of China (Grant Nos. 11320101005, 11175060, 11375054, and 11075046), and the China-Korean Joint Foundation (Grant No. 2012DFG02230).

  7. Dust storm events over Delhi: verification of dust AOD forecasts with satellite and surface observations

    Science.gov (United States)

    Singh, Aditi; Iyengar, Gopal R.; George, John P.

    2016-05-01

    Thar desert located in northwest part of India is considered as one of the major dust source. Dust storms originate in Thar desert during pre-monsoon season, affects large part of Indo-Gangetic plains. High dust loading causes the deterioration of the ambient air quality and degradation in visibility. Present study focuses on the identification of dust events and verification of the forecast of dust events over Delhi and western part of IG Plains, during the pre-monsoon season of 2015. Three dust events have been identified over Delhi during the study period. For all the selected days, Terra-MODIS AOD at 550 nm are found close to 1.0, while AURA-OMI AI shows high values. Dust AOD forecasts from NCMRWF Unified Model (NCUM) for the three selected dust events are verified against satellite (MODIS) and ground based observations (AERONET). Comparison of observed AODs at 550 nm from MODIS with NCUM predicted AODs reveals that NCUM is able to predict the spatial and temporal distribution of dust AOD, in these cases. Good correlation (~0.67) is obtained between the NCUM predicted dust AODs and location specific observations available from AERONET. Model under-predicted the AODs as compared to the AERONET observations. This may be mainly because the model account for only dust and no anthropogenic activities are considered. The results of the present study emphasize the requirement of more realistic representation of local dust emission in the model both of natural and anthropogenic origin, to improve the forecast of dust from NCUM during the dust events.

  8. Dust Evolution in Galaxy Cluster Simulations

    Science.gov (United States)

    Gjergo, Eda; Granato, Gian Luigi; Murante, Giuseppe; Ragone-Figueroa, Cinthia; Tornatore, Luca; Borgani, Stefano

    2018-06-01

    We implement a state-of-the-art treatment of the processes affecting the production and Interstellar Medium (ISM) evolution of carbonaceous and silicate dust grains within SPH simulations. We trace the dust grain size distribution by means of a two-size approximation. We test our method on zoom-in simulations of four massive (M200 ≥ 3 × 1014M⊙) galaxy clusters. We predict that during the early stages of assembly of the cluster at z ≳ 3, where the star formation activity is at its maximum in our simulations, the proto-cluster regions are rich in dusty gas. Compared to the case in which only dust production in stellar ejecta is active, if we include processes occurring in the cold ISM,the dust content is enhanced by a factor 2 - 3. However, the dust properties in this stage turn out to be significantly different from those observationally derived for the average Milky Way dust, and commonly adopted in calculations of dust reprocessing. We show that these differences may have a strong impact on the predicted spectral energy distributions. At low redshift in star forming regions our model reproduces reasonably well the trend of dust abundances over metallicity as observed in local galaxies. However we under-produce by a factor of 2 to 3 the total dust content of clusters estimated observationally at low redshift, z ≲ 0.5 using IRAS, Planck and Herschel satellites data. This discrepancy does not subsist by assuming a lower sputtering efficiency, which erodes dust grains in the hot Intracluster Medium (ICM).

  9. Dust in the Quasar Wind (Artist Concept)

    Science.gov (United States)

    2007-01-01

    Dusty grains -- including tiny specks of the minerals found in the gemstones peridot, sapphires and rubies -- can be seen blowing in the winds of a quasar, or active black hole, in this artist's concept. The quasar is at the center of a distant galaxy. Astronomers using NASA's Spitzer Space Telescope found evidence that such quasar winds might have forged these dusty particles in the very early universe. The findings are another clue in an ongoing cosmic mystery: where did all the dust in our young universe come from? Dust is crucial for efficient star formation as it allows the giant clouds where stars are born to cool quickly and collapse into new stars. Once a star has formed, dust is also needed to make planets and living creatures. Dust has been seen as far back as when the universe was less than a tenth of its current age, but how did it get there? Most dust in our current epoch forms in the winds of evolved stars that did not exist when the universe was young. Theorists had predicted that winds from quasars growing in the centers of distant galaxies might be a source of this dust. While the environment close to a quasar is too hot for large molecules like dust grains to survive, dust has been found in the cooler, outer regions. Astronomers now have evidence that dust is created in these outer winds. Using Spitzer's infrared spectrograph instrument, scientists found a wealth of dust grains in a quasar called PG2112+059 located at the center of a galaxy 8 billion light-years away. The grains - including corundum (sapphires and rubies); forsterite (peridot); and periclase (naturally occurring in marble) - are not typically found in galaxies without quasars, suggesting they might have been freshly formed in the quasar's winds.

  10. High Latitude Dust in the Earth System

    Science.gov (United States)

    Bullard, Joanna E.; Baddock, Matthew; Bradwell, Tom; Crusius, John; Darlington, Eleanor; Gaiero, Diego; Gasso, Santiago; Gisladottir, Gudrun; Hodgkins, Richard; McCulloch, Robert; hide

    2016-01-01

    Natural dust is often associated with hot, subtropical deserts, but significant dust events have been reported from cold, high latitudes. This review synthesizes current understanding of high-latitude (> or = 50degN and > or = 40degS) dust source geography and dynamics and provides a prospectus for future research on the topic. Although the fundamental processes controlling aeolian dust emissions in high latitudes are essentially the same as in temperate regions, there are additional processes specific to or enhanced in cold regions. These include low temperatures, humidity, strong winds, permafrost and niveo-aeolian processes all of which can affect the efficiency of dust emission and distribution of sediments. Dust deposition at high latitudes can provide nutrients to the marine system, specifically by contributing iron to high-nutrient, low-chlorophyll oceans; it also affects ice albedo and melt rates. There have been no attempts to quantify systematically the expanse, characteristics, or dynamics of high-latitude dust sources. To address this, we identify and compare the main sources and drivers of dust emissions in the Northern (Alaska, Canada, Greenland, and Iceland) and Southern (Antarctica, New Zealand, and Patagonia) Hemispheres. The scarcity of year-round observations and limitations of satellite remote sensing data at high latitudes are discussed. It is estimated that under contemporary conditions high-latitude sources cover >500,000 sq km and contribute at least 80-100 Tg/yr1 of dust to the Earth system (approx. 5% of the global dust budget); both are projected to increase under future climate change scenarios.

  11. Challenged by migration: Europe's options

    NARCIS (Netherlands)

    Constant, Amelie F.; Zimmermann, Klaus F.

    2017-01-01

    This paper examines the migration and labour mobility in the European Union and elaborates on their importance for the existence of the EU. Against all measures of success, the current public debate seems to suggest that the political consensus that migration is beneficial is broken. This comes with

  12. Radionuclide migration studies in soil

    International Nuclear Information System (INIS)

    Marumo, J.T.

    1989-01-01

    In this work a brief description about retention and migration parameters of radionuclides in soil, including main methods to determine the distribution coefficient (K) are given. Some of several factors that can act on the migration are also mentioned. (author) [pt

  13. South-South Migration and Remittances

    OpenAIRE

    Ratha, Dilip; Shaw, William

    2007-01-01

    South-South Migration and Remittances reports on preliminary results from an ongoing effort to improve data on bilateral migration stocks. It sets out some working hypotheses on the determinants and socioeconomic implications of South-South migration. Contrary to popular perception that migration is mostly a South-North phenomenon, South-South migration is large. Available data from nation...

  14. Measuring International Migration in Azerbaijan

    Directory of Open Access Journals (Sweden)

    Serhat Yüksel

    2018-01-01

    Full Text Available International migration significantly affects economic, social, cultural, and political factors of the country. Owing to this situation, it can be said that the reasons of international migration should be analyzed in order to control this problem. The purpose of this study is to determine the influencing factors of international migration in Azerbaijan. In this scope, annual data of 11 explanatory variables for the period of 1995–2015 was analyzed via Multivariate Adaptive Regression Splines (MARS method. According to the results of this analysis, it was identified that people prefer to move other countries in case of high unemployment rates. In addition, the results of the study show that population growth and high mortality rate increases the migration level. While considering these results, it was recommended that Azerbaijan should focus on these aspects to control international migration problem.

  15. Wages, Welfare Benefits and Migration.

    Science.gov (United States)

    Kennan, John; Walker, James R

    2010-05-01

    Differences in economic opportunities give rise to strong migration incentives, across regions within countries, and across countries. In this paper we focus on responses to differences in welfare benefits across States. We apply the model developed in Kennan and Walker (2008), which emphasizes that migration decisions are often reversed, and that many alternative locations must be considered. We model individual decisions to migrate as a job search problem. A worker starts the life-cycle in some home location and must determine the optimal sequence of moves before settling down. The model is sparsely parameterized. We estimate the model using data from the National Longitudinal Survey of Youth (1979). Our main finding is that income differences do help explain the migration decisions of young welfare-eligible women, but large differences in benefit levels provide surprisingly weak migration incentives.

  16. Asian dust events of April 1998

    Science.gov (United States)

    Husar, R.B.; Tratt, D.M.; Schichtel, B.A.; Falke, S.R.; Li, F.; Jaffe, D.; Gasso, S.; Gill, T.; Laulainen, N.S.; Lu, F.; Reheis, M.C.; Chun, Y.; Westphal, D.; Holben, B.N.; Gueymard, C.; McKendry, I.; Kuring, N.; Feldman, G.C.; McClain, C.; Frouin, R.J.; Merrill, J.; DuBois, D.; Vignola, F.; Murayama, T.; Nickovic, S.; Wilson, W.E.; Sassen, K.; Sugimoto, N.; Malm, W.C.

    2001-01-01

    On April 15 and 19, 1998, two intense dust storms were generated over the Gobi desert by springtime low-pressure systems descending from the northwest. The windblown dust was detected and its evolution followed by its yellow color on SeaWiFS satellite images, routine surface-based monitoring, and through serendipitous observations. The April 15 dust cloud was recirculating, and it was removed by a precipitating weather system over east Asia. The April 19 dust cloud crossed the Pacific Ocean in 5 days, subsided to the surface along the mountain ranges between British Columbia and California, and impacted severely the optical and the concentration environments of the region. In east Asia the dust clouds increased the albedo over the cloudless ocean and land by up to 10-20%, but it reduced the near-UV cloud reflectance, causing a yellow coloration of all surfaces. The yellow colored backscattering by the dust eludes a plausible explanation using simple Mie theory with constant refractive index. Over the West Coast the dust layer has increased the spectrally uniform optical depth to about 0.4, reduced the direct solar radiation by 30-40%, doubled the diffuse radiation, and caused a whitish discoloration of the blue sky. On April 29 the average excess surface-level dust aerosol concentration over the valleys of the West Coast was about 20-50 ??g/m3 with local peaks >100 ??g/m3. The dust mass mean diameter was 2-3 ??m, and the dust chemical fingerprints were evident throughout the West Coast and extended to Minnesota. The April 1998 dust event has impacted the surface aerosol concentration 2-4 times more than any other dust event since 1988. The dust events were observed and interpreted by an ad hoc international web-based virtual community. It would be useful to set up a community-supported web-based infrastructure to monitor the global aerosol pattern for such extreme aerosol events, to alert and to inform the interested communities, and to facilitate collaborative

  17. Neutrophilic respiratory tract inflammation and peripheral blood neutrophilia after grain sorghum dust extract challenge.

    Science.gov (United States)

    Von Essen, S G; O'Neill, D P; McGranaghan, S; Olenchock, S A; Rennard, S I

    1995-11-01

    To determine if inhalation of grain sorghum dust in the laboratory would cause neutrophilic upper and lower respiratory tract inflammation in human volunteers, as well as systemic signs of illness. Prospective. University of Nebraska Medical Center. Thirty normal volunteers. Inhalation challenge with 20 mL of a nebulized solution of filter-sterilized grain sorghum dust extract (GSDE). One group received prednisone, 20 mg for 2 days, prior to the challenge. Bronchoscopy with bronchoalveolar lavage (BAL) was performed 24 h after challenge, with samples collected as bronchial and alveolar fractions. Findings included visible signs of airways inflammation, quantified as the bronchitis index. The percentage of bronchial neutrophils was significantly increased in those challenged with GSDE vs the control solution, Hanks' balanced salt solution (40.3 +/- 4.5% vs 14.3 +/- 5.1%, p grain dust extract. To explain the increase in peripheral blood neutrophil counts, the capacity of the peripheral blood neutrophils to migrate in chemotaxis experiments was examined. The results demonstrate an increase in peripheral blood neutrophils and an increase in chemotactic responsiveness. Inhalation challenge with a grain dust extract causes respiratory tract inflammation and a peripheral blood neutrophilia. One reason for this may be an increase in activated peripheral blood neutrophils.

  18. Migrating and herniating hydatid cysts

    International Nuclear Information System (INIS)

    Koc, Zafer; Ezer, Ali

    2008-01-01

    Objective: To present the prevalence and imaging findings of patients with hydatid disease (HD) showing features of migration or herniation of the hydatid cysts (HCs) and underline the clinical significance of this condition. Materials and methods: Between May 2003 and June 2006, 212 patients with HD were diagnosed by abdomen and/or thorax CT, searched for migrating or herniating HC. Imaging findings of 7 patients (5 women, 2 men with an age range of 19-63 years; mean ± S.D., 44 ± 19 years) with HD showing transdiaphragmatic migration (6 subjects) or femoral herniation (1 subject) were evaluated. Diagnosis of all the patients were established by pathologic examination and migration or herniation was confirmed by surgery in all patients. Results: Liver HD were identified in 169 (79.7%) of 212 patients with HD. Transdiaphragmatic migration of HCs were identified in 6 (3.5%) of the 169 patients with liver HD. In one patient, femoral herniation of the retroperitoneal HC into the proximal anterior thigh was identified. All of these seven patients exhibiting migration or herniation of HCs had active HCs including 'daughter cysts'. Two patients had previous surgery because of liver HD and any supradiaphragmatic lesion was not noted before operation. Findings of migration or herniation were confirmed by surgery. Conclusion: Active HCs may show migration or herniation due to pressure difference between the anatomic cavities, and in some of the patients, by contribution of gravity. Previous surgery may be a complementary factor for migration as seen in two of our patients. The possibility of migration or herniation in patients with HD should be considered before surgery

  19. Current Migration Movements in Europe

    Directory of Open Access Journals (Sweden)

    Jelena Zlatković Winter

    2004-09-01

    Full Text Available After a brief historical review of migrations in Europe, the paper focuses on current migration trends and their consequences. At the end of the 1950s, Western Europe began to recruit labour from several Mediterranean countries – Italy, Spain, Portugal and former Yugoslavia, and later from Morocco, Algeria, Tunisia and Turkey. Some countries, such as France, Great Britain and the Netherlands, recruited also workers from their former colonies. In 1970 Germany had the highest absolute number of foreigners, followed by France, and then Switzerland and Belgium. The total number of immigrants in Western Europe was twelve million. During the 1970s mass recruitment of foreign workers was abandoned, and only the arrival of their family members was permitted, which led to family reunification in the countries of employment. Europe closed its borders, with the result that clandestine migration increased. The year 1989 was a turning point in the history of international migrations. The political changes in Central and Eastern Europe brought about mass migration to the West, which culminated in the so-called “mass movement of 1989–1990”. The arrival of ethnic Germans in Germany, migration inside and outside of the territory of the former Soviet Union, an increase in the number of asylum seekers and displaced persons, due to armed conflicts, are – according to the author – the main traits of current migration. The main part of the paper discusses the causes and effects of this mass wave, as well as trends in labour migration, which is still present. The second part of the paper, after presenting a typology of migrations, deals with the complex processes that brought about the formation of new communities and led to the phenomenon of new ethnic minorities and to corresponding migration policies in Western European countries that had to address these issues.

  20. Austrian emission inventory for dust

    International Nuclear Information System (INIS)

    Winiwarter, W.; Trenker, C.; Hoeflinger, W.

    2001-09-01

    For the first time, Austrian emissions of anthropogenic particulate matter emissions to the atmosphere have been estimated. Results have been reported as total suspended particles (TSP) as well as for the fractions of particles smaller than 10 μm or 2.5 μm aerodynamic diameter (PM 10 , PM 2.5 ), respectively. Base years for the inventory were 1990, 1995 and 1999. Excluded from this assessment is wind blown dust, which has been considered a natural source here. National statistics have been applied, specifically those also used previously in the Austrian air pollution inventory (OLI). Emission factors have been taken from literature compilations, only for exceptional cases specific Austrian assessments were performed or original literature on emission measurements was consulted. Resuspension of dust by road traffic emerged as the most important source. For the size fraction of PM 10 this source contributed about half of the emissions, when applying the calculation scheme by the U.S. EPA. While this scheme is widely used and well documented, its validity is currently subject of intense scientific debate. As these results do not seem to coincide with ambient air measurements, resuspension of road dust is considered separately and not now included in the national total. The sum of all other sources increases from 75,000 t of TSP in 1990 and 1995 to 77,000 t in 1999, while both PM 10 and PM 2.5 exhibit decreasing tendency (at 45,000 t and 26,000 t in 1999, respectively). The increase in TSP derives from increasing traffic and friction related emissions (tire wear, break wear), decrease of the finer particulate matter is due to reductions in firewood consumption for domestic heating. Most important source sectors are fugitive emissions from material transfer in industry as well as the building industry and the tilling of agricultural land. Common to these sources is the high uncertainty of available data. Wood combustion is the most important of the non

  1. The Spatial Variation of Dust Particulate Matter Concentrations during Two Icelandic Dust Storms in 2015

    Directory of Open Access Journals (Sweden)

    Pavla Dagsson-Waldhauserova

    2016-06-01

    Full Text Available Particulate matter mass concentrations and size fractions of PM1, PM2.5, PM4, PM10, and PM15 measured in transversal horizontal profile of two dust storms in southwestern Iceland are presented. Images from a camera network were used to estimate the visibility and spatial extent of measured dust events. Numerical simulations were used to calculate the total dust flux from the sources as 180,000 and 280,000 tons for each storm. The mean PM15 concentrations inside of the dust plumes varied from 10 to 1600 µg·m−3 (PM10 = 7 to 583 µg·m−3. The mean PM1 concentrations were 97–241 µg·m−3 with a maximum of 261 µg·m−3 for the first storm. The PM1/PM2.5 ratios of >0.9 and PM1/PM10 ratios of 0.34–0.63 show that suspension of volcanic materials in Iceland causes air pollution with extremely high PM1 concentrations, similar to polluted urban areas in Europe or Asia. Icelandic volcanic dust consists of a higher proportion of submicron particles compared to crustal dust. Both dust storms occurred in relatively densely inhabited areas of Iceland. First results on size partitioning of Icelandic dust presented here should challenge health authorities to enhance research in relation to dust and shows the need for public dust warning systems.

  2. Kuiper Belt Dust Grains as a Source of Interplanetary Dust Particles

    Science.gov (United States)

    Liou, Jer-Chyi; Zook, Herbert A.; Dermott, Stanley F.

    1996-01-01

    The recent discovery of the so-called Kuiper belt objects has prompted the idea that these objects produce dust grains that may contribute significantly to the interplanetary dust population. In this paper, the orbital evolution of dust grains, of diameters 1 to 9 microns, that originate in the region of the Kuiper belt is studied by means of direct numerical integration. Gravitational forces of the Sun and planets, solar radiation pressure, as well as Poynting-Robertson drag and solar wind drag are included. The interactions between charged dust grains and solar magnetic field are not considered in the model. Because of the effects of drag forces, small dust grains will spiral toward the Sun once they are released from their large parent bodies. This motion leads dust grains to pass by planets as well as encounter numerous mean motion resonances associated with planets. Our results show that about 80% of the Kuiper belt grains are ejected from the Solar System by the giant planets, while the remaining 20% of the grains evolve all the way to the Sun. Surprisingly, the latter dust grains have small orbital eccentricities and inclinations when they cross the orbit of the Earth. This makes them behave more like asteroidal than cometary-type dust particles. This also enhances their chances of being captured by the Earth and makes them a possible source of the collected interplanetary dust particles; in particular, they represent a possible source that brings primitive/organic materials from the outer Solar System to the Earth. When collisions with interstellar dust grains are considered, however, Kuiper belt dust grains around 9 microns appear likely to be collisionally shattered before they can evolve toward the inner part of the Solar System. The collision destruction can be applied to Kuiper belt grains up to about 50 microns. Therefore, Kuiper belt dust grains within this range may not be a significant part of the interplanetary dust complex in the inner Solar

  3. Dust grains from the heart of supernovae

    Science.gov (United States)

    Bocchio, M.; Marassi, S.; Schneider, R.; Bianchi, S.; Limongi, M.; Chieffi, A.

    2016-03-01

    Dust grains are classically thought to form in the winds of asymptotic giant branch (AGB) stars. However, there is increasing evidence today for dust formation in supernovae (SNe). To establish the relative importance of these two classes of stellar sources of dust, it is important to know the fraction of freshly formed dust in SN ejecta that is able to survive the passage of the reverse shock and be injected in the interstellar medium. With this aim, we have developed a new code, GRASH_Rev, that allows following the dynamics of dust grains in the shocked SN ejecta and computing the time evolution of the mass, composition, and size distribution of the grains. We considered four well-studied SNe in the Milky Way and Large Magellanic Cloud: SN 1987A, CasA, the Crab nebula, and N49. These sources have been observed with both Spitzer and Herschel, and the multiwavelength data allow a better assessment the mass of warm and cold dust associated with the ejecta. For each SN, we first identified the best explosion model, using the mass and metallicity of the progenitor star, the mass of 56Ni, the explosion energy, and the circumstellar medium density inferred from the data. We then ran a recently developed dust formation model to compute the properties of freshly formed dust. Starting from these input models, GRASH_Rev self-consistently follows the dynamics of the grains, considering the effects of the forward and reverse shock, and allows predicting the time evolution of the dust mass, composition, and size distribution in the shocked and unshocked regions of the ejecta. All the simulated models aagree well with observations. Our study suggests that SN 1987A is too young for the reverse shock to have affected the dust mass. Hence the observed dust mass of 0.7-0.9 M⊙ in this source can be safely considered as indicative of the mass of freshly formed dust in SN ejecta. Conversely, in the other three SNe, the reverse shock has already destroyed between 10-40% of the

  4. Dust limit management strategy in tokamaks

    International Nuclear Information System (INIS)

    Rosanvallon, S.; Grisolia, C.; Andrew, P.; Ciattaglia, S.; Delaporte, P.; Douai, D.; Garnier, D.; Gauthier, E.; Gulden, W.; Hong, S.H.; Pitcher, S.; Rodriguez, L.; Taylor, N.; Tesini, A.; Vartanian, S.; Vatry, A.; Wykes, M.

    2009-01-01

    Dust is produced in tokamaks by the interaction between the plasma and the plasma facing components. Dust has not yet been of a major concern in existing tokamaks mainly because the quantity is small and these devices are not nuclear facilities. However, in ITER and in future reactors, it will represent operational and potential safety issues. From a safety point of view, in order to control the potential dust hazard, the current ITER strategy is based on a defense in depth approach designed to provide reliable confinement systems, to avoid failures, and to measure and minimise the dust inventory. In addition, R and D is put in place for optimisation of the proposed methods, such as improvement of measurement, dust cleaning and the reduction of dust production. The aim of this paper is to present the approach for the control of the dust inventory, relying on the monitoring of envelope values and the development of removal techniques already developed in the existing tokamaks or plasma dedicated devices or which will need further research and development in order to be integrated in ITER.

  5. Dust limit management strategy in tokamaks

    Science.gov (United States)

    Rosanvallon, S.; Grisolia, C.; Andrew, P.; Ciattaglia, S.; Delaporte, P.; Douai, D.; Garnier, D.; Gauthier, E.; Gulden, W.; Hong, S. H.; Pitcher, S.; Rodriguez, L.; Taylor, N.; Tesini, A.; Vartanian, S.; Vatry, A.; Wykes, M.

    2009-06-01

    Dust is produced in tokamaks by the interaction between the plasma and the plasma facing components. Dust has not yet been of a major concern in existing tokamaks mainly because the quantity is small and these devices are not nuclear facilities. However, in ITER and in future reactors, it will represent operational and potential safety issues. From a safety point of view, in order to control the potential dust hazard, the current ITER strategy is based on a defense in depth approach designed to provide reliable confinement systems, to avoid failures, and to measure and minimise the dust inventory. In addition, R&D is put in place for optimisation of the proposed methods, such as improvement of measurement, dust cleaning and the reduction of dust production. The aim of this paper is to present the approach for the control of the dust inventory, relying on the monitoring of envelope values and the development of removal techniques already developed in the existing tokamaks or plasma dedicated devices or which will need further research and development in order to be integrated in ITER.

  6. Hypervelocity Dust Injection for Plasma Diagnostic Applications

    Science.gov (United States)

    Ticos, Catalin

    2005-10-01

    Hypervelocity micron-size dust grain injection was proposed for high-temperature magnetized plasma diagnosis. Multiple dust grains are launched simultaneously into high temperature plasmas at several km/s or more. The hypervelocity dust grains are ablated by the electron and ion fluxes. Fast imaging of the resulting luminous plumes attached to each grain is expected to yield local magnetic field vectors. Combination of multiple local magnetic field vectors reproduces 2D or even 3D maps of the internal magnetic field topology. Key features of HDI are: (1) a high spatial resolution, due to a relatively small transverse size of the elongated tail, and (2) a small perturbation level, as the dust grains introduce negligible number of particles compared to the plasma particle inventory. The latter advantage, however, could be seriously compromised if the gas load from the accelerator has an unobstructed access to the diagnosed plasma. Construction of a HDI diagnostic for National Spherical Torus Experiment (NSTX), which includes a coaxial plasma gun for dust grain acceleration, is underway. Hydrogen and deuterium gas discharges inside accelerator are created by a ˜ 1 mF capacitor bank pre-charged up to 10 kV. The diagnostic apparatus also comprises a dust dispenser for pre-loading the accelerator with dust grains, and an imaging system that has a high spatial and temporal resolution.

  7. Testing of a Plasmadynamic Hypervelocity Dust Accelerator

    Science.gov (United States)

    Ticos, Catalin M.; Wang, Zhehui; Dorf, Leonid A.; Wurden, G. A.

    2006-10-01

    A plasmadynamic accelerator for microparticles (or dust grains) has been designed, built and tested at Los Alamos National laboratory. The dust grains are expected to be accelerated to hypervelocities on the order of 1-30 km/s, depending on their size. The key components of the plasmadynamic accelerator are a coaxial plasma gun operated at 10 kV, a dust dispenser activated by a piezoelectric transducer, and power and remote-control systems. The coaxial plasma gun produces a high density (10^18 cm-3) and low temperature (˜ 1 eV) plasma in deuterium ejected by J x B forces, which provides drag on the dust particles in its path. Carbon dust particles will be used, with diameters from 1 to 50 μm. The plasma parameters produced in the coaxial gun are presented and their implication to dust acceleration is discussed. High speed dust will be injected in the National Spherical Torus Experiment to measure the pitch angle of magnetic field lines.

  8. Featured Image: Making Dust in the Lab

    Science.gov (United States)

    Kohler, Susanna

    2017-12-01

    This remarkable photograph (which spans only 10 m across; click for a full view) reveals what happens when you form dust grains in a laboratory under conditions similar to those of interstellar space. The cosmic life cycle of dust grains is not well understood we know that in the interstellar medium (ISM), dust is destroyed at a higher rate than it is produced by stellar sources. Since the amount of dust in the ISM stays constant, however, there must be additional sources of dust production besides stars. A team of scientists led by Daniele Fulvio (Pontifical Catholic University of Rio de Janeiro and the Max Planck Institute for Astronomy at the Friedrich Schiller University Jena) have now studied formation mechanisms of dust grains in the lab by mimicking low-temperature ISM conditions and exploring how, under these conditions, carbonaceous materials condense from gas phase to form dust grains. To read more about their results and see additional images, check out the paper below.CitationDaniele Fulvio et al 2017 ApJS 233 14. doi:10.3847/1538-4365/aa9224

  9. THE MEASUREMENT AND DISTRIBUTION OF WOOD DUST

    Directory of Open Access Journals (Sweden)

    Andrea Rosario Proto

    2010-03-01

    Full Text Available In Italy, the woodworking industry presents many issues in terms of occupational health and safety. This study on exposure to wood dust could contribute to the realization of a prevention model in order to limit exposure to carcinogenic agents to the worker. The sampling methodology illustrated the analysis of dust emissions from the woodworking machinery in operation throughout the various processing cycles. The quantitative and qualitative assessment of exposure was performed using two different methodologies. The levels of wood dust were determined according to EN indications and sampling was conducted using IOM and Cyclon personal samplers. The qualitative research of wood dust was performed using an advanced laser air particle counter. This allowed the number of particles present to be counted in real time. The results obtained allowed for an accurate assessment of the quality of the dust emitted inside the workplace during the various processing phases. The study highlighted the distribution of air particles within the different size classes, the exact number of both thin and ultra-thin dusts, and confirmed the high concentration of thin dust particles which can be very harmful to humans.

  10. Pebble Bed Reactor Dust Production Model

    Energy Technology Data Exchange (ETDEWEB)

    Abderrafi M. Ougouag; Joshua J. Cogliati

    2008-09-01

    The operation of pebble bed reactors, including fuel circulation, can generate graphite dust, which in turn could be a concern for internal components; and to the near field in the remote event of a break in the coolant circuits. The design of the reactor system must, therefore, take the dust into account and the operation must include contingencies for dust removal and for mitigation of potential releases. Such planning requires a proper assessment of the dust inventory. This paper presents a predictive model of dust generation in an operating pebble bed with recirculating fuel. In this preliminary work the production model is based on the use of the assumption of proportionality between the dust production and the normal force and distance traveled. The model developed in this work uses the slip distances and the inter-pebble forces computed by the authors’ PEBBLES. The code, based on the discrete element method, simulates the relevant static and kinetic friction interactions between the pebbles as well as the recirculation of the pebbles through the reactor vessel. The interaction between pebbles and walls of the reactor vat is treated using the same approach. The amount of dust produced is proportional to the wear coefficient for adhesive wear (taken from literature) and to the slip volume, the product of the contact area and the slip distance. The paper will compare the predicted volume with the measured production rates. The simulation tallies the dust production based on the location of creation. Two peak production zones from intra pebble forces are predicted within the bed. The first zone is located near the pebble inlet chute due to the speed of the dropping pebbles. The second peak zone occurs lower in the reactor with increased pebble contact force due to the weight of supported pebbles. This paper presents the first use of a Discrete Element Method simulation of pebble bed dust production.

  11. Pebble Bed Reactor Dust Production Model

    International Nuclear Information System (INIS)

    Abderrafi M. Ougouag; Joshua J. Cogliati

    2008-01-01

    The operation of pebble bed reactors, including fuel circulation, can generate graphite dust, which in turn could be a concern for internal components; and to the near field in the remote event of a break in the coolant circuits. The design of the reactor system must, therefore, take the dust into account and the operation must include contingencies for dust removal and for mitigation of potential releases. Such planning requires a proper assessment of the dust inventory. This paper presents a predictive model of dust generation in an operating pebble bed with recirculating fuel. In this preliminary work the production model is based on the use of the assumption of proportionality between the dust production and the normal force and distance traveled. The model developed in this work uses the slip distances and the inter-pebble forces computed by the authors PEBBLES. The code, based on the discrete element method, simulates the relevant static and kinetic friction interactions between the pebbles as well as the recirculation of the pebbles through the reactor vessel. The interaction between pebbles and walls of the reactor vat is treated using the same approach. The amount of dust produced is proportional to the wear coefficient for adhesive wear (taken from literature) and to the slip volume, the product of the contact area and the slip distance. The paper will compare the predicted volume with the measured production rates. The simulation tallies the dust production based on the location of creation. Two peak production zones from intra pebble forces are predicted within the bed. The first zone is located near the pebble inlet chute due to the speed of the dropping pebbles. The second peak zone occurs lower in the reactor with increased pebble contact force due to the weight of supported pebbles. This paper presents the first use of a Discrete Element Method simulation of pebble bed dust production

  12. Geochemistry and radionuclide migration

    International Nuclear Information System (INIS)

    Isherwood, D.

    1978-01-01

    Theoretically, the geochemical barrier can provide a major line of defense in protecting the biosphere from the hazards of nuclear waste. The most likely processes involved are easily identified. Preliminary investigations using computer modeling techniques suggest that retardation is an effective control on radionuclide concentrations. Ion exchange reactions slow radionuclide migration and allow more time for radioactive decay and dispersion. For some radionuclides, solubility alone may limit concentrations to less than the maximum permissible now considered acceptable by the Federal Government. The effectiveness of the geochemical barrier is ultimately related to the repository site characteristics. Theory alone tells us that geochemical controls will be most efficient in an environment that provides for maximum ion exchange and the precipitation of insoluble compounds. In site selection, consideration should be given to rock barriers with high ion exchange capacity that might also act as semi-permeable membranes. Also important in evaluating the site's potential for effective geochemical controls are the oxidation potentials, pH and salinity of the groundwater

  13. NNDC database migration project

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, Thomas W; Dunford, Charles L [U.S. Department of Energy, Brookhaven Science Associates (United States)

    2004-03-01

    NNDC Database Migration was necessary to replace obsolete hardware and software, to be compatible with the industry standard in relational databases (mature software, large base of supporting software for administration and dissemination and replication and synchronization tools) and to improve the user access in terms of interface and speed. The Relational Database Management System (RDBMS) consists of a Sybase Adaptive Server Enterprise (ASE), which is relatively easy to move between different RDB systems (e.g., MySQL, MS SQL-Server, or MS Access), the Structured Query Language (SQL) and administrative tools written in Java. Linux or UNIX platforms can be used. The existing ENSDF datasets are often VERY large and will need to be reworked and both the CRP (adopted) and CRP (Budapest) datasets give elemental cross sections (not relative I{gamma}) in the RI field (so it is not immediately obvious which of the old values has been changed). But primary and secondary intensities are now available on the same scale. The intensity normalization has been done for us. We will gain access to a large volume of data from Budapest and some of those gamma-ray intensity and energy data will be superior to what we already have.

  14. Radionuclide migration in soils

    Energy Technology Data Exchange (ETDEWEB)

    Demir, M [Ingenieurgesellschaft Bonnenberg und Drescher, Juelich (Germany, F.R.)

    1979-01-01

    Unplanned releases from a nuclear installation - e.g., leakage from a storage tank or other incident - can result in the escape of contaminants such as U, Pu, Cs, Sr, T etc. Nuclide transport through the ground is governed by characteristics of the subsurface hydrology and the specific nuclides under consideration. Unsaturated soil layers result in a transport rate so low as to negligible. Radionuclides reaching the ground water are assumed to endanger human life because of potential uncontrolled ingestion. The most dangerous nuclides are long-lived and not absorbed, or very poorly absorbed, in the soil. During migration of nuclides through saturated soil layers, the concentration can be reduced by dilution. Preliminary results indicate that tritium is spread with ground water velocity. Its concentration can be reduced only by diffusion, dispersion and radioactive decay. Alpha-emitters are strongly retained velocities of alpha-emitters are approximately one thousandth (10/sup -3/) that of T. Transport velocities of Cs and Sr are approximately one hundreth (10/sup -2/) and one tenth (10/sup -1/) that of T respectively.

  15. Radionuclide migration in soils

    International Nuclear Information System (INIS)

    Demir, M.

    1979-01-01

    Unplanned releases from a nuclear installation - e.g., leakage from a storage tank or other incident - can result in the escape of contaminants such as U, Pu, Cs, Sr, T etc. Nuclide transport through the ground is governed by characteristics of the subsurface hydrology and the specific nuclides under consideration. Unsaturated soil layers result in a transport rate so low as to negligible. Radionuclides reaching the ground water are assumed to endanger human life because of potential uncontrolled ingestion. The most dangerous nuclides are long-lived and not absorbed, or very poorly absorbed, in the soil. During migration of nuclides through saturated soil layers, the concentration can be reduced by dilution. Preliminary results indicate that tritium is spread with ground water velocity. Its concentration can be reduced only by diffusion, dispersion and radioactive decay. Alpha-emitters are strongly retained velocities of alpha-emitters are approximately one thousandth (10 -3 ) that of T. Transport velocities of Cs and Sr are approximately one hundreth (10 -2 ) and one tenth (10 -1 ) that of T respectively. (orig./HP) [de

  16. Psychosocial Aspects of Migration

    Directory of Open Access Journals (Sweden)

    Ayla Tuzcu

    2014-02-01

    Full Text Available The incident of migration that occurs as a result of the mobility of individuals between various regions and is considered a social change process brings along various factors. Among these factors, the most important one is the culture of the new society where the immigrant begins to live and the process of adaptation with this culture. Individuals from different cultures are required to live together, cope with differences and overcome the difficulties. The process of adaptation to the new lifestyle might cause the individual to have some feelings such as loneliness, socially isolation, being alienated, being regretful and self-depreciation, and consequently experience a greater stress. Being unable to cope with stress efficiently creates risks in individuals in terms of health problems such as anxiety and depression. Healthcare professionals are required to evaluate life styles, difficulties and coping levels of immigrants in order to protect and develop their mental health. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(1.000: 56-66

  17. MIGRATION IMPACT ON ECONOMICAL SITUATION

    Directory of Open Access Journals (Sweden)

    Virginia COJOCARU

    2016-01-01

    Full Text Available This paper presents recent trends and flows of labor migration and its impact on economic and social life. Main aim of this research sets up the influence of the migration on the European economics and its competitiveness. Methods of research are: method of comparison, analysis method, method of deduction, method of statistics, modeling method. The economic impact of migration has been intensively studied but is still often driven by ill-informed perceptions, which, in turn, can lead to public antagonism towards migration. These negative views risk jeopardising efforts to adapt migration policies to the new economic and demographic challenges facing many countries. Migration Policy looks at the evidence for how immigrants affect the economy in three main areas: The labour market, public purse and economic growth. In Europe, the scope of labour mobility greatly increased within the EU/EFTA zones following the EU enlargements of 2004, 2007 and 2014-2015. This added to labour markets’ adjustment capacity. Recent estimates suggest that as much as a quarter of the asymmetric labour market shock – that is occurring at different times and with different intensities across countries – may have been absorbed by migration within a year.

  18. Vulnerable to HIV / AIDS. Migration.

    Science.gov (United States)

    Fernandez, I

    1998-01-01

    This special report discusses the impact of globalization, patterns of migration in Southeast Asia, gender issues in migration, the links between migration and HIV/AIDS, and spatial mobility and social networks. Migrants are particularly marginalized in countries that blame migrants for transmission of infectious and communicable diseases and other social ills. Effective control of HIV/AIDS among migrant and native populations requires a multisectoral approach. Programs should critically review the privatization of health care services and challenge economic models that polarize the rich and the poor, men and women, North and South, and migrant and native. Programs should recognize the equality between locals and migrants in receipt of health services. Countermeasures should have input from migrants in order to reduce the conditions that increase vulnerability to HIV/AIDS. Gender-oriented research is needed to understand women's role in migration. Rapid assessment has obscured the human dimension of migrants' vulnerability to HIV. Condom promotion is not enough. Migration is a major consequence of globalization, which holds the promise, real or imagined, of prosperity for all. Mass migration can be fueled by explosive regional developments. In Southeast Asia, migration has been part of the process of economic development. The potential to emigrate increases with greater per capita income. "Tiger" economies have been labor importers. Safe sex is not practiced in many Asian countries because risk is not taken seriously. Migrants tend to be used as economic tools, without consideration of social adjustment and sex behavior among singles.

  19. Simulation of dust-acoustic waves

    International Nuclear Information System (INIS)

    Winske, D.; Murillo, M.S.; Rosenberg, M.

    1998-01-01

    The authors use molecular dynamics (MD) and particle-in-cell (PIC) simulation methods to investigate the dispersion relation of dust-acoustic waves in a one-dimensional, strongly coupled (Coulomb coupling parameter Λ = ratio of the Coulomb energy to the thermal energy = 120) dusty plasma. They study both cases where the dust is represented by a small number of simulation particles that form into a regular array structure (crystal limit) as well as where the dust is represented by a much larger number of particles (fluid limit)

  20. Backscattering Moessbauer spectroscopy of Martian dust

    International Nuclear Information System (INIS)

    Bertelsen, P.; Madsen, M. B.; Binau, C. S.; Goetz, W.; Gunnlaugsson, H. P.; Hviid, S. F.; Kinch, K. M.; Klingelhoefer, G.; Leer, K.; Madsen, D. E.; Merrison, J.; Olsen, M.; Squyres, S. W.

    2005-01-01

    We report on the determination of the mineralogy of the atmospherically suspended Martian dust particles using backscattering 57 Fe Moessbauer spectroscopy on dust accumulated onto the magnets onboard the Mars Exploration Rovers. The spectra can be interpreted in terms of minerals of igneous origin, and shows only limited, if any, amounts of secondary minerals that may have formed in the presence of liquid water. These findings suggest that the dust has formed in a dry environment over long time in the history of the planet.

  1. Dust and radon: the legal implications

    International Nuclear Information System (INIS)

    Van Sittert, J.M.O.

    1990-01-01

    It is known that radon gas is not generally considered to be a major problem when encountered in the working environment. However, in its process of decay, a series of four short lived daughter products are formed. In a dust-laden atmosphere these daughter products, which are ionized readily, attach to the particulate material and when inhaled are deposited in the alveoli of the lungs. Therefore, if respirable dust is controlled, the effects of radon daughters will also be minimized. The legal requirements for dust control in South Africa and their implications are discussed. 1 ill

  2. Is there dust in galactic haloes

    International Nuclear Information System (INIS)

    Greenberg, J.M.; Ferrini, F.; Pisa Univ.; Barsella, B.; Aiello, S.

    1987-01-01

    The ubiquitous presence of dust within the disks of spiral galaxies is well established. The authors predict that the presence of dust in these regions may be revealed in bright edge-on galaxies, especially by using the polarization of the scattered light from the symmetric lanes. The detection of scattered light above the galactic plane may be an indicator that the parent galaxy has not suffered close encounters with other galaxies at least within the timescale required to establish the dust layers. (author)

  3. Residual dust charges in discharge afterglow

    International Nuclear Information System (INIS)

    Coueedel, L.; Mikikian, M.; Boufendi, L.; Samarian, A. A.

    2006-01-01

    An on-ground measurement of dust-particle residual charges in the afterglow of a dusty plasma was performed in a rf discharge. An upward thermophoretic force was used to balance the gravitational force. It was found that positively charged, negatively charged, and neutral dust particles coexisted for more than 1 min after the discharge was switched off. The mean residual charge for 200-nm-radius particles was measured. The dust particle mean charge is about -5e at a pressure of 1.2 mbar and about -3e at a pressure of 0.4 mbar

  4. Income Inequality and Migration in Vietnam

    OpenAIRE

    NGUYEN, Tien Dung

    2012-01-01

    In this paper, we have analyzed the recent trends in income inequality, internal and international migrations and investigated the impact of migration on income distribution in Vietnam. Our analysis shows that the effects of migration on income inequality vary with different types of migration, depending on who migrate and where they migrate. Foreign remittances tend to flow toward more affluent households, and they increase income inequality. By contrast, domestic remittances accrue more to ...

  5. Effect of non-Maxwellian particle trapping and dust grain charging on dust acoustic solitary waves

    International Nuclear Information System (INIS)

    Rubab, N.; Murtaza, G.; Mushtaq, A.

    2006-01-01

    The role of adiabatic trapped ions on a small but finite amplitude dust acoustic wave, including the effect of adiabatic dust charge variation, is investigated in an unmagnetized three-component dusty plasma consisting of electrons, ions and massive micron sized negatively charged dust particulates. We have assumed that electrons and ions obey (r,q) velocity distribution while the dust species is treated fluid dynamically. It is found that the dynamics of dust acoustic waves is governed by a modified r dependent Korteweg-de Vries equation. Further, the spectral indices (r,q) affect the charge fluctuation as well as the trapping of electrons and ions and consequently modify the dust acoustic solitary wave

  6. [The productive structure and migration].

    Science.gov (United States)

    Fernandez, M

    1980-01-01

    The author discusses the possibility of determining the proper approach to the study of migration, with a focus on the importance of global, structural, and historical analysis of the phenomenon. A general theoretical outline is presented that tends to show migration as an integral part of the process of social change. The sociological focus on modernization as a theoretical guide influencing the study of migration in Latin America is evaluated. The concept of overpopulation is explained in relation to the migratory process, with reference to capitalist and non-capitalist forms of production.

  7. Migration of accreting giant planets

    Science.gov (United States)

    Robert, C.; Crida, A.; Lega, E.; Méheut, H.

    2017-09-01

    Giant planets forming in protoplanetary disks migrate relative to their host star. By repelling the gas in their vicinity, they form gaps in the disk's structure. If they are effectively locked in their gap, it follows that their migration rate is governed by the accretion of the disk itself onto the star, in a so-called type II fashion. Recent results showed however that a locking mechanism was still lacking, and was required to understand how giant planets may survive their disk. We propose that planetary accretion may play this part, and help reach this slow migration regime.

  8. MIGRATION – EFFECTS AND SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Raluca Cruceru

    2012-12-01

    Full Text Available There are three main flows that influence workforce performance—worker migration, the dissemination of knowledge, and overseas development assistance. For the present paper we decided to deal with the analyses of these three, yet mainly migration. We considered it to be one of the most important phenomenon existent on the market at this hour and with the highest negative impact on the economic and social situation. We presented a case study regarding the situation of migration in Romania and the main candidates to Romanian intelligence imports, the main issues and possible solutions to the problems encountered.

  9. Dust storm detection using random forests and physical-based ...

    Indian Academy of Sciences (India)

    arid areas of the Middle. East. Due to the influences of dust aerosols on climate and human daily activities, dust detection plays a crucial role in environmental and climatic studies. Detection of dust storms is critical to accurately under- stand dust ...

  10. Dust analysis on board the Destiny+ mission to 3200 Phaethon

    Science.gov (United States)

    Krüger, H.; Kobayashi, M.; Arai, T.; Srama, R.; Sarli, B. V.; Kimura, H.; Moragas-Klostermeyer, G.; Soja, R.; Altobelli, N.; Grün, E.

    2017-09-01

    The Japanese Destiny+ spacecraft will be launched to the active asteroid 3200 Phaethon in 2022. Among the proposed core payload is an in-situ dust instrument based on the Cassini Cosmic Dust Analyzer. We use the ESA Interplanetary Meteoroid Engineering Model (IMEM), to study detection conditions and fluences of interplanetary and interstellar dust with a dust analyzer on board Destiny+.

  11. Respirable quartz hazard associated with coal mine roof bolter dust

    International Nuclear Information System (INIS)

    Joy, G.J.; Beck, T.W.; Listak, J.M.

    2010-01-01

    Pneumoconiosis has been reported to be increasing among underground coal miners in the Southern Appalachian Region. The National Institute for Occupational Safety and Health conducted a study to examine the particle size distribution and quartz content of dust generated by the installation of roof bolts in mines. Forty-six bulk samples of roof bolting machine pre-cleaner cyclone dump dust and collector box dust were collected from 26 underground coal mines. Real-time and integrated airborne respirable dust concentrations were measured on 3 mining sections in 2 mines. The real-time airborne dust concentrations profiles were examined to identify any concentration changes that might be associated with pre-cleaner cyclone dust discharge events. The study showed that bolter dust is a potential inhalation hazard due to the fraction of dust less than 10 μm in size, and the quartz content of the dust. The pre-cleaner cyclone dust was significantly larger than the collector box dust, indicating that the pre-cleaner functioned properly in removing the larger dust size fraction from the airstream. However, the pre-cleaner dust still contained a substantial amount of respirable dust. It was concluded that in order to maintain the effectiveness of a roof bolter dust collector, periodic removal of dust is required. Appropriate work procedures and equipment are necessary to minimize exposure during this cleaning task. 13 refs., 3 tabs., 2 figs.

  12. Plasma particle lofting : experimental investigation of dust removal force

    NARCIS (Netherlands)

    Heijmans, L.C.J.; Nijdam, S.

    2015-01-01

    Dust is everywhere. Sometimes it's harmless, but sometimes it needs to be removed. Especially in modern optical machinery, dust control can be of vital importance. In this research we look at dust on a surface. We focus on the behaviour under influence of a plasma. The dust particles will stick to a

  13. Investigation of piston bowl geometry and speed effects in a motored HSDI diesel engine using a CFD against a quasi-dimensional model

    International Nuclear Information System (INIS)

    Rakopoulos, C.D.; Kosmadakis, G.M.; Pariotis, E.G.

    2010-01-01

    The present work investigates the effect of varying the combustion chamber geometry and engine rotational speed on the gas flow and temperature field, using a new quasi-dimensional engine simulation model in conjunction with an in-house developed computational fluid dynamics (CFD) code served to validate the predicted in-cylinder flow field and gas temperature distribution calculated by the quasi-dimensional model, for three alternative piston bowl geometries and three rotational speeds. This CFD code can simulate three-dimensional curvilinear domains using the finite volume method in a collocated grid; it solves the generalized transport equation for the conservation of mass, momentum and energy, and incorporates the standard k-ε turbulence model with some slight modifications to introduce the compressibility of a fluid in generalized coordinates. On the other hand, the quasi-dimensional model solves the general transport equation for the conservation of mass and energy by a finite volume method throughout the entire in-cylinder volume, while for the estimation of the flow field a new simplified three dimensional air motion model is used. To compare these two models the in-cylinder spatial and temporal temperature distribution, the mean cylinder pressure diagram, as well as the mean in-cylinder radial and axial velocity are examined, for the three piston bowl geometries and the three speeds, for a high speed direct injection (HSDI) diesel engine operating under motoring conditions. From the comparison of calculated results, it becomes apparent that the two models predict similar in-cylinder temperature distributions and mean air velocity fields at each crank angle, for all cases examined. Thus, it is shown that the quasi-dimensional model with the proposed simplified air motion model is capable of capturing the physical effect of combustion chamber geometry and speed on the in-cylinder velocity and temperature field, while needing significantly lower computing

  14. Terrestrial Analogs for Surface Properties Associated with Impact Cratering on the Moon - Self-secondary Impact Features at Kings Bowl, Idaho

    Science.gov (United States)

    Matiella Novak, M. A.; Zanetti, M.; Neish, C.; Kukko, A.; Fan, K.; Heldmann, J.; Hughes, S. S.

    2017-12-01

    The Kings Bowl (KB) eruptive fissure and lava field, located in the southern end of Craters of the Moon National Monument, Idaho, is an ideal location for planetary analogue field studies of surface properties related to volcanic and impact processes. Here we look at possible impact features present in the KB lava field near the main vent that resulted in squeeze-ups of molten lava from beneath a semi-solid lava lake crust. These may have been caused by the ejection of blocks during the phreatic eruption that formed the Kings Bowl pit, and their subsequent impact into a partially solidified lava pond. We compare and contrast these features with analogous self-secondary impact features, such as irregular, rimless secondary craters ("splash craters") observed in lunar impact melt deposits, to better understand how self-secondary impacts determine the surface properties of volcanic and impact crater terrains. We do this by analyzing field measurements of these features, as well as high-resolution DEM data collected through the Kinematic LiDAR System (KLS), both of which give us feature dimensions and distributions. We then compare these data with self-secondary impact features on the Moon and related surface roughness constrained through Lunar Reconnaissance Orbiter observations (Mini-RF and LROC NACs). Possible self-secondary impact features can be found in association with many lunar impact craters. These are formed when ballistic ejecta from the crater falls onto the ejecta blanket and melt surrounding the newly formed crater. Self-secondary impact features involving impact melt deposits are particularly useful to study because the visibly smooth melt texture serves to highlight the impact points in spacecraft imagery. The unusual morphology of some of these features imply that they formed when the melt had not yet completely solidified, strongly suggesting a source of impactors from the primary crater itself. We will also discuss ongoing efforts to integrate field

  15. The physics of wind-blown sand and dust.

    Science.gov (United States)

    Kok, Jasper F; Parteli, Eric J R; Michaels, Timothy I; Karam, Diana Bou

    2012-10-01

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  16. Experimental Method for Measuring Dust Load on Surfaces in Rooms

    DEFF Research Database (Denmark)

    Lengweiler, Philip; Nielsen, Peter V.; Moser, Alfred

    A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms, there is a n......A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms......, there is a need for better understanding of the mechanism of dust deposition and resuspension. With the presented experimental setup, the dust load on surfaces in a channel can be measured as a function of the environmental and surface conditions and the type of particles under controlled laboratory conditions....

  17. Inactivation of dust mites, dust mite allergen, and mold from carpet.

    Science.gov (United States)

    Ong, Kee-Hean; Lewis, Roger D; Dixit, Anupma; MacDonald, Maureen; Yang, Mingan; Qian, Zhengmin

    2014-01-01

    Carpet is known to be a reservoir for biological contaminants, such as dust mites, dust mite allergen, and mold, if it is not kept clean. The accumulation of these contaminants in carpet might trigger allergies or asthma symptoms in both children and adults. The purpose of this study is to compare methods for removal of dust mites, dust mite allergens, and mold from carpet. Carpets were artificially worn to simulate 1 to 2 years of wear in a four-person household. The worn carpets were inoculated together with a common indoor mold (Cladosporium species) and house dust mites and incubated for 6 weeks to allow time for dust mite growth on the carpet. The carpets were randomly assigned to one of the four treatment groups. Available treatment regimens for controlling carpet contaminants were evaluated through a literature review and experimentation. Four moderately low-hazard, nondestructive methods were selected as treatments: vacuuming, steam-vapor, Neem oil (a natural tree extract), and benzalkonium chloride (a quaternary ammonium compound). Steam vapor treatment demonstrated the greatest dust mite population reduction (p 0.05) for both physical and chemical methods. The steam-vapor treatment effectively killed dust mites and denatured dust mite allergen in the laboratory environment.

  18. Mineralogy of Interplanetary Dust Particles from the Comet Giacobini-Zinner Dust Stream Collections

    Science.gov (United States)

    Nakamura-Messenger, K.; Messenger, S.; Westphal, A. J.; Palma, R. L.

    2015-01-01

    The Draconoid meteor shower, originating from comet 21P/Giacobini-Zinner, is a low-velocity Earth-crossing dust stream that had a peak anticipated flux on Oct. 8, 2012. In response to this prediction, NASA performed dedicated stratospheric dust collections to target interplanetary dust particles (IDPs) from this comet stream on Oct 15-17, 2012 [3]. Twelve dust particles from this targeted collection were allocated to our coordinated analysis team for studies of noble gas (Univ. Minnesota, Minnesota State Univ.), SXRF and Fe-XANES (SSL Berkeley) and mineralogy/isotopes (JSC). Here we report a mineralogical study of 3 IDPs from the Draconoid collection..

  19. Study on the alternative mitigation of cement dust spread by capturing the dust with fogging method

    Science.gov (United States)

    Purwanta, Jaka; Marnoto, Tjukup; Setyono, Prabang; Handono Ramelan, Ari

    2017-12-01

    The existence of a cement plant impact the lives of people around the factory site. For example the air quality, which is polluted by dust. Cement plant has made various efforts to mitigate the generated dust, but there are still alot of dust fly inground either from the cement factory chimneys or transportation. The purpose of this study was to conduct a review of alternative mitigation of the spread of dust around the cement plant. This study uses research methods such as collecting secondary data which includes data of rain density, the average rains duration, wind speed and direction as well as data of dust intensity quality around PT. Semen Gresik (Persero) Tbk.Tuban plant. A soft Wind rose file is used To determine the wind direction propensity models. The impact on the spread of dust into the environment is determined using secondary data monitoring air quality. Results of the study is that the mitigation of dust around the cement plant is influenced by natural factors, such as the tendency of wind direction, rain fall and rainy days, and the rate of dust emission from the chimney. The alternative means proposed is an environmental friendly fogging dust catcher.

  20. The composition of circumstellar and interstellar dust

    NARCIS (Netherlands)

    Tielens, AGGM; Woodward, CE; Biscay, MD; Shull, JM

    2001-01-01

    A large number of solid dust components have been identified through analysis of stardust recovered from meteorites, and analysis of IR observations of circumstellar shells and the interstellar medium. These include graphite, hydrogenated amorphous carbon, diamond, PAHs, silicon-, iron-, and

  1. He Puff System For Dust Detector Upgrade

    International Nuclear Information System (INIS)

    Rais, B.; Skinner, C.H.; Roquemore, A.L.

    2010-01-01

    Local detection of surface dust is needed for the safe operation of next-step magnetic fusion devices such as ITER. An electrostatic dust detector, based on a 5 cm x 5 cm grid of interlocking circuit traces biased to 50 V, has been developed to detect dust on remote surfaces and was successfully tested for the first time on the National Spherical Torus Experiment (NSTX). We report on a helium puff system that clears residual dust from this detector and any incident debris or fibers that might cause a permanent short circuit. The entire surface of the detector was cleared of carbon particles by two consecutive helium puffs delivered by three nozzles of 0.45 mm inside diameter. The optimal configuration was found to be with the nozzles at an angle of 30o with respect to the surface of the detector and a helium backing pressure of 6 bar.

  2. Surface acoustic wave dust deposition monitor

    Science.gov (United States)

    Fasching, G.E.; Smith, N.S. Jr.

    1988-02-12

    A system is disclosed for using the attenuation of surface acoustic waves to monitor real time dust deposition rates on surfaces. The system includes a signal generator, a tone-burst generator/amplifier connected to a transmitting transducer for converting electrical signals into acoustic waves. These waves are transmitted through a path defining means adjacent to a layer of dust and then, in turn, transmitted to a receiving transducer for changing the attenuated acoustic wave to electrical signals. The signals representing the attenuated acoustic waves may be amplified and used in a means for analyzing the output signals to produce an output indicative of the dust deposition rates and/or values of dust in the layer. 8 figs.

  3. Stochastic Models of Molecule Formation on Dust

    Science.gov (United States)

    Charnley, Steven; Wirstroem, Eva

    2011-01-01

    We will present new theoretical models for the formation of molecules on dust. The growth of ice mantles and their layered structure is accounted for and compared directly to observations through simulation of the expected ice absorption spectra

  4. Obliquely propagating dust-density waves

    International Nuclear Information System (INIS)

    Piel, A.; Arp, O.; Klindworth, M.; Melzer, A.

    2008-01-01

    Self-excited dust-density waves are experimentally studied in a dusty plasma under microgravity. Two types of waves are observed: a mode inside the dust volume propagating in the direction of the ion flow and another mode propagating obliquely at the boundary between the dusty plasma and the space charge sheath. The dominance of oblique modes can be described in the frame of a fluid model. It is shown that the results fom the fluid model agree remarkably well with a kinetic electrostatic model of Rosenberg [J. Vac. Sci. Technol. A 14, 631 (1996)]. In the experiment, the instability is quenched by increasing the gas pressure or decreasing the dust density. The critical pressure and dust density are well described by the models

  5. 25 years of dust acoustic waves

    Science.gov (United States)

    Merlino, Robert L.; Merlino

    2014-12-01

    The dust acoustic wave (DAW) was first discussed by P. K. Shukla in May of 1989 at the First Capri Workshop on Dusty Plasmas. In the past 25 years, the subsequent publication of the linear and nonlinear properties of the DAW (Rao, N. N., Shukla, P. K. and Yu, M. Y. 1990 Planet. Space Sci. 38, 543) has generated and sustained a large body of theoretical and experimental research that has clarified the physics of collective effects in dusty plasmas. A unique feature of the DAW is that it can be observed (literally) using laser illumination and high-speed videography, revealing details of wave-particle interactions at an unprecedented single particle level. This paper attempts to review some of the contributions and extensions of dust acoustic wave physics, as well as identify recent findings that illustrate the potential importance of this dust wave in the agglomeration of dust particles.

  6. Coir dust reinforced recycled polypropylene composites

    International Nuclear Information System (INIS)

    Santos, Bianca B. dos; Costa, Marysilvia F. da; Thire, Rossana M. da S.M.

    2015-01-01

    The environmental impacts caused by disposed plastics encourage the search for new alternatives. Recycling polymers leads to the degradation of their mechanical properties, which can be modified by the addition of fillers. In this paper, recycled polypropylene from plastic cups with 2%, 5% and 10% of coir dust were produced with and without the addition of additives. These composites were characterized by tensile tests, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy on the fracture surface. It was verified the effectiveness of the addition of coir dust in improving the elasticity modulus of recycled polypropylene besides the effectiveness of additives used in promoting the adhesion of the powder to the matrix. However, higher levels of coir dust caused the appearance of air bubbles inside the material, which contributed to its embrittlement. The addition of coir dust promoted a decrease in the degree of polypropylene crystallinity. (author)

  7. Surface System Dust Mitigation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort will perform a detailed examination of dust mitigation and tolerance strategies for connections and mechanisms to be employed on the lunar...

  8. House dust mite control measures for asthma

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    BACKGROUND: The major allergen in house dust comes from mites. Chemical, physical and combined methods of reducing mite allergen levels are intended to reduce asthma symptoms in people who are sensitive to house dust mites. OBJECTIVES: To assess the effects of reducing exposure to house dust mite...... antigens in the homes of people with mite-sensitive asthma. SEARCH STRATEGY: PubMed and The Cochrane Library (last searches Nov 2007), reference lists. SELECTION CRITERIA: Randomised trials of mite control measures vs placebo or no treatment in people with asthma known to be sensitive to house dust mites......), the standardised mean difference was 0.00 (95% confidence interval (CI) -0.10 to 0.10). There were no statistically significant differences either in number of patients improved (relative risk 1.01, 95% CI 0.80 to 1.27), asthma symptom scores (standardised mean difference -0.04, 95% CI -0.15 to 0...

  9. The Marriage of Gas and Dust

    Science.gov (United States)

    Price, D. J.; Laibe, G.

    2015-10-01

    Dust-gas mixtures are the simplest example of a two fluid mixture. We show that when simulating such mixtures with particles or with particles coupled to grids a problem arises due to the need to resolve a very small length scale when the coupling is strong. Since this is occurs in the limit when the fluids are well coupled, we show how the dust-gas equations can be reformulated to describe a single fluid mixture. The equations are similar to the usual fluid equations supplemented by a diffusion equation for the dust-to-gas ratio or alternatively the dust fraction. This solves a number of numerical problems as well as making the physics clear.

  10. Nanotube Electrodes for Dust Mitigation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Dust mitigation is critical to the survivability of vehicle and infrastructure components and systems and to the safety of astronauts during EVAs and planetary...

  11. Solar-Panel Dust Accumulation and Cleanings

    Science.gov (United States)

    2005-01-01

    Air-fall dust accumulates on the solar panels of NASA's Mars Exploration Rovers, reducing the amount of sunlight reaching the solar arrays. Pre-launch models predicted steady dust accumulation. However, the rovers have been blessed with occasional wind events that clear significant amounts of dust from the solar panels. This graph shows the effects of those panel-cleaning events on the amount of electricity generated by Spirit's solar panels. The horizontal scale is the number of Martian days (sols) after Spirit's Jan. 4, 2005, (Universal Time) landing on Mars. The vertical scale indicates output from the rover's solar panels as a fraction of the amount produced when the clean panels first opened. Note that the gradual declines are interrupted by occasional sharp increases, such as a dust-cleaning event on sol 420.

  12. Review of the ITER diagnostics suite for erosion, deposition, dust and tritium measurements

    Energy Technology Data Exchange (ETDEWEB)

    Reichle, R., E-mail: roger.reichle@iter.org [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Andrew, P. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Bates, P. [F4E, Torres Diagonal Litoral B3, Barcelona (Spain); Bede, O.; Casal, N.; Choi, C.H.; Barnsley, R. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Damiani, C. [F4E, Torres Diagonal Litoral B3, Barcelona (Spain); Bertalot, L. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Dubus, G. [F4E, Torres Diagonal Litoral B3, Barcelona (Spain); Ferreol, J.; Jagannathan, G.; Kocan, M.; Leipold, F.; Lisgo, S.W.; Martin, V.; Palmer, J.; Pearce, R. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Philipps, V. [Institut für Energieforschung – Plasmaphysik, Forschungszentrum Jülich GmbH, Association EURATOM – Forschungszentrum Jülich, D-52425 Jülich (Germany); Pitts, R.A. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); and others

    2015-08-15

    Dust and tritium inventories in the vacuum vessel have upper limits in ITER that are set by nuclear safety requirements. Erosion, migration and re-deposition of wall material together with fuel co-deposition will be largely responsible for these inventories. The diagnostic suite required to monitor these processes, along with the set of the corresponding measurement requirements is currently under review given the recent decision by the ITER Organization to eliminate the first carbon/tungsten (C/W) divertor and begin operations with a full-W variant Pitts et al. [1]. This paper presents the result of this review as well as the status of the chosen diagnostics.

  13. Investigations of Wind/WAVES Dust Impacts

    Science.gov (United States)

    St Cyr, O. C.; Wilson, L. B., III; Rockcliffe, K.; Mills, A.; Nieves-Chinchilla, T.; Adrian, M. L.; Malaspina, D.

    2017-12-01

    The Wind spacecraft launched in November 1994 with a primary goal to observe and understand the interaction between the solar wind and Earth's magnetosphere. The waveform capture detector, TDS, of the radio and plasma wave investigation, WAVES [Bougeret et al., 1995], onboard Wind incidentally detected micron-sized dust as electric field pulses from the recollection of the impact plasma clouds (an unintended objective). TDS has detected over 100,000 dust impacts spanning almost two solar cycles; a dataset of these impacts has been created and was described in Malaspina & Wilson [2016]. The spacecraft continues to collect data about plasma, energetic particles, and interplanetary dust impacts. Here we report on two investigations recently conducted on the Wind/WAVES TDS database of dust impacts. One possible source of dust particles is the annually-recurring meteor showers. Using the nine major showers defined by the American Meteor Society, we compared dust count rates before, during, and after the peak of the showers using averaging windows of varying duration. However, we found no statistically significant change in the dust count rates due to major meteor showers. This appears to be an expected result since smaller grains, like the micron particles that Wind is sensitive to, are affected by electromagnetic interactions and Poynting-Robertson drag, and so are scattered away from their initial orbits. Larger grains tend to be more gravitationally dominated and stay on the initial trajectory of the parent body so that only the largest dust grains (those that create streaks as they burn up in the atmosphere) are left in the orbit of the parent body. Ragot and Kahler [2003] predicted that coronal mass ejections (CMEs) near the Sun could effectively scatter dust grains of comparable size to those observed by Wind. Thus, we examined the dust count rates immediately before, during, and after the passage of the 350 interplanetary CMEs observed by Wind over its 20+ year

  14. MRI of neuronal migration disorders

    International Nuclear Information System (INIS)

    Engelbrecht, V.

    1996-01-01

    Twenty-one MRI examinations of the brain were performed in 19 children with neuronal migration disorders. Multiplanar oriented spin-echo sequences were on a scanner with 1.5 T. In 8 children we performed an additional turbo-inversion recovery (TIR) sequence. Results of sonography or CT from five children were compared with MRI scans. Using the actual nomenclature, we found the following migration disorders: Lissencephaly (n=6), cobblestone lissencephaly with Walker-Warbung syndrome (WWS) (n=2), polymicrogyria and schizencephaly (n=2), focal heterotopia (n=5), diffuse heterotopie (n=2) and hemimegalencephaly (n=2). MRI was superior to CT and sonography in all children. Except for the two boys with WWS, the TIR sequence was the best to demonstrate the changes in migration disorder because of the high contrast between gray and white matter. We demonstrate the characteristic features of the different migration disorders and compare them with the existing literature. (orig.) [de

  15. The migration challenge for PAYG

    Czech Academy of Sciences Publication Activity Database

    Aslanyan, Gurgen

    2014-01-01

    Roč. 27, č. 4 (2014), s. 1023-1038 ISSN 0933-1433 Institutional support: RVO:67985998 Keywords : public pension s * PAYG * unskilled migration Subject RIV: AH - Economics Impact factor: 1.109, year: 2014

  16. The migration challenge for PAYG

    Czech Academy of Sciences Publication Activity Database

    Aslanyan, Gurgen

    2014-01-01

    Roč. 27, č. 4 (2014), s. 1023-1038 ISSN 0933-1433 Institutional support: PRVOUK-P23 Keywords : public pension s * PAYG * unskilled migration Subject RIV: AH - Economics Impact factor: 1.109, year: 2014

  17. Labour market frictions and migration

    NARCIS (Netherlands)

    Cremers, Jan

    2016-01-01

    The 4th contribution to the series INT-AR papers is dedicated to the methods of assessing labour market frictions. The paper provides a (brief) international comparison of the role of labour migration in solving these frictions.

  18. Fluid migration studies in salt

    International Nuclear Information System (INIS)

    Shefelbine, H.C.; Raines, G.E.

    1980-01-01

    This discussion will be limited to the migration of water trapped in the rock salt under the influence of the heat field produced by nuclear waste. This is of concern because hypotheticl scenarios have been advanced in which this fluid movement allows radionuclides to escape to the biosphere. While portions of these scenarios are supported by observation, none of the complete scenarios has been demonstrated. The objectives of the present fluid migration studies are two-fold: 1. determine the character of the trapped fluid in terms of quantity, habitat and chemical constituents; and 2. define the mechanisms that cause the fluid to migrate toward heat sources. Based on the observations to date, fluid migration will not have a major impact on repository integrity. However, the above objectives will be pursued until the impacts, if any, can be quantified

  19. Effort Estimation in BPMS Migration

    Directory of Open Access Journals (Sweden)

    Christopher Drews

    2018-04-01

    Full Text Available Usually Business Process Management Systems (BPMS are highly integrated in the IT of organizations and are at the core of their business. Thus, migrating from one BPMS solution to another is not a common task. However, there are forces that are pushing organizations to perform this step, e.g. maintenance costs of legacy BPMS or the need for additional functionality. Before the actual migration, the risk and the effort must be evaluated. This work provides a framework for effort estimation regarding the technical aspects of BPMS migration. The framework provides questions for BPMS comparison and an effort evaluation schema. The applicability of the framework is evaluated based on a simplified BPMS migration scenario.

  20. Ice nucleation properties of mineral dusts

    OpenAIRE

    Steinke, Isabelle

    2013-01-01

    Ice nucleation in clouds has a significant impact on the global hydrological cycle as well as on the radiative budget of the Earth. The AIDA cloud chamber was used to investigate the ice nucleation efficiency of various atmospherically relevant mineral dusts. From experiments with Arizona Test Dust (ATD) a humidity and temperature dependent ice nucleation active surface site density parameterization was developed to describe deposition nucleation at temperatures above 220 K. Based...

  1. Ideas about the study of dust

    International Nuclear Information System (INIS)

    Andriesse, C.D.

    1974-01-01

    Agreement seems to exist about the general idea that a dust particle is a tiny piece of solid material, with some atomic lattice and bonding electrons. But questions like: how large are dust particles, what is their chemical composition, how do they scatter and absorb light, are answered differently when different spectral features are discussed. However, observations do give a number of keys for a reasonable particle model. (G.T.H.)

  2. Carbonaceous Components in the Comet Halley Dust

    Science.gov (United States)

    Fomenkova, M. N.; Chang, S.; Mukhin, L. M.

    1994-01-01

    Cometary grains containing large amounts of carbon and/or organic matter (CHON) were discovered by in situ measurements of comet Halley dust composition during VEGA and GIOTTO flyby missions. In this paper, we report the classification of these cometary, grains by means of cluster analysis, discuss the resulting compositional groups, and compare them with substances observed or hypothesized in meteorites, interplanetary dust particles, and the interstellar medium. Grains dominated by carbon and/or organic matter (CHON grains) represent approx. 22% of the total population of measured cometary dust particles. They, usually contain a minor abundance of rock-forming elements as well. Grains having organic material are relatively more abundant in the vicinity of the nucleus than in the outer regions of the coma, which suggests decomposition of the organics in the coma environment. The majority of comet Halley organic particles are multicomponent mixtures of carbon phases and organic compounds. Possibly, the cometary CHON grains may be related to kerogen material of an interstellar origin in carbonaceous meteorites. Pure carbon grains, hydrocarbons and polymers of cyanopolyynes, and multi-carbon monoxides are present in cometary dust as compositionally simple and distinctive components among a variety of others. There is no clear evidence of significant presence of pure formaldehyde or HCN polymers in Halley dust particles. The diversity of types of cometary organic compounds is consistent with the inter-stellar dust model of comets and probably reflects differences in composition of precursor dust. Preservation of this heterogeneity among submicron particles suggest the gentle formation of cometary, nucleus by aggregation of interstellar dust in the protosolar nebula without complete mixing or chemical homogenization at the submicron level.

  3. DIRT: Dust InfraRed Toolbox

    Science.gov (United States)

    Pound, Marc W.; Wolfire, Mark G.; Mundy, Lee G.; Teuben, Peter; Lord, Steve

    2011-02-01

    DIRT is a Java applet for modelling astrophysical processes in circumstellar dust shells around young and evolved stars. With DIRT, you can: select and display over 500,000 pre-run model spectral energy distributions (SEDs) find the best-fit model to your data set account for beam size in model fitting manipulate data and models with an interactive viewer display gas and dust density and temperature profiles display model intensity profiles at various wavelengths

  4. [Linguistic concerns and lexical mechanisms in the "Introducción a la Historia Natural, y a la Geografía Fisica de España" by William Bowles].

    Science.gov (United States)

    Díez de Revenga Torres, Pilar; Puche Lorenzo, Miguel Angel

    2007-01-01

    Linguistic mechanisms of 18th century scientific language are studied in the first Natural History text originally drafted in Spanish. William Bowles describes linguistic concerns in science over the definition of terms that refer to realities in the three natural kingdoms. Diatopic and diastratic variants and definition procedures are reported, demonstrating the importance of these texts to the History of Science and the History of the Spanish Language.

  5. Novel diagnostics for dust in space, Laboratory and fusion plasmas

    International Nuclear Information System (INIS)

    Castaldo, C.

    2011-01-01

    In situ diagnostics for mobile dust, based on dust impact ionization phenomena, as well as silica aerogel dust collectors are discussed for applications to space and fusion plasmas. The feasibility of an electro-optical probe to detect hypervelocity (>1 km/s) dust particles in tokamaks is evaluated. For quiescent plasmas, a diagnostic of submicron dust based on measurements of plasma fluctuation spectra can be used (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Quasar Winds as Dust Factories at High Redshift

    OpenAIRE

    Elvis, Martin; Marengo, Massimo; Karovska, Margarita

    2003-01-01

    Winds from AGN and quasars will form large amounts of dust, as the cool gas in these winds passes through the (pressure, temperature) region where dust is formed in AGB stars. Conditions in the gas are benign to dust at these radii. As a result quasar winds may be a major source of dust at high redshifts, obviating a difficulty with current observations, and requiring far less dust to exist at early epochs.

  7. Return Migration and Working Choices

    OpenAIRE

    TANI, Massimiliano; MAHUTEAU, Stéphane

    2008-01-01

    Collective Action to Support the Reintegration of Return Migrants in their Country of Origin (MIREM) This paper uses the recent survey carried out in the framework of the MIREM project on returnees to Algeria, Morocco and Tunisia and studies the duration of emigration and the labour force status upon returning. The results suggest that age and the year of emigration play a central role in the migration decision, but they do not support the hypothesis that the duration of migration is deter...

  8. Roosts and migrations of swallows

    OpenAIRE

    Winkler, David W.

    2006-01-01

    Swallows of the north temperate zone display a wide variety of territorial behaviour during the breeding season, but as soon as breeding is over, they all appear to adopt a pattern of independent diurnal foraging interleaved with aggregation every night in dense roosts. Swallows generally migrate during the day, feeding on the wing. On many stretches of their annual journeys, their migrations can thus be seen as the simple spatial translation of nocturnal roost sites with foraging routes stra...

  9. International Student Migration to Germany

    OpenAIRE

    Donata Bessey

    2007-01-01

    This paper presents first empirical evidence on international student migration to Germany. I use a novel approach that analyzes student mobility using an augmented gravity equation and find evidence of strong network effects and of the importance of distance - results familiar from the empirical migration literature. However, the importance of disposable income in the home country does not seem to be too big for students, while the fact of being a politically unfree country decreases migrati...

  10. Effort Estimation in BPMS Migration

    OpenAIRE

    Drews, Christopher; Lantow, Birger

    2018-01-01

    Usually Business Process Management Systems (BPMS) are highly integrated in the IT of organizations and are at the core of their business. Thus, migrating from one BPMS solution to another is not a common task. However, there are forces that are pushing organizations to perform this step, e.g. maintenance costs of legacy BPMS or the need for additional functionality. Before the actual migration, the risk and the effort must be evaluated. This work provides a framework for effort estimation re...

  11. Palaeo-dust records: A window to understanding past environments

    Science.gov (United States)

    Marx, Samuel K.; Kamber, Balz S.; McGowan, Hamish A.; Petherick, Lynda M.; McTainsh, Grant H.; Stromsoe, Nicola; Hooper, James N.; May, Jan-Hendrik

    2018-06-01

    Dust entrainment, transport over vast distances and subsequent deposition is a fundamental part of the Earth system. Yet the role and importance of dust has been underappreciated, due largely to challenges associated with recognising dust in the landscape and interpreting its depositional history. Despite these challenges, interest in dust is growing. Technical advances in remote sensing and modelling have improved understanding of dust sources and production, while advances in sedimentology, mineralogy and geochemistry (in particular) have allowed dust to be more easily distinguished within sedimentary deposits. This has facilitated the reconstruction of records of dust emissions through time. A key advance in our understanding of dust has occurred following the development of methods to geochemically provenance (fingerprint) dust to its source region. This ability has provided new information on dust transport pathways, as well as the reach and impact of dust. It has also expanded our understanding of the processes driving dust emissions over decadal to millennial timescales through linking dust deposits directly to source area conditions. Dust provenance studies have shown that dust emission, transport and deposition are highly sensitive to variability in climate. They also imply that dust emissions are not simply a function of the degree of aridity in source areas, but respond to a more complex array of conditions, including sediment availability. As well as recording natural variability, dust records are also shown to sensitively track the impact of human activity. This is reflected by both changing dust emission rates and changing dust chemistry. Specific examples of how dust responds to, and records change, are provided with our work on dust emissions from Australia, the most arid inhabited continent and the largest dust source in the Southern Hemisphere. These case studies show that Australian dust emissions reflect hydro-climate variability, with

  12. Thermo-Oxidation of Tokamak Carbon Dust

    International Nuclear Information System (INIS)

    J.W. Davis; B.W.N. Fitzpatrick; J.P. Sharpe; A.A. Haasz

    2008-01-01

    The oxidation of dust and flakes collected from the DIII-D tokamak, and various commercial dust specimens, has been measured at 350 C and 2.0 kPa O 2 pressure. Following an initial small mass loss, most of the commercial dust specimens showed very little effect due to O 2 exposure. Similarly, dust collected from underneath DIII-D tiles, which is thought to comprise largely Grafoil(trademark) particulates, also showed little susceptibility to oxidation at this temperature. However, oxidation of the dust collected from tile surfaces has led to ∼ 18% mass loss after 8 hours; thereafter, little change in mass was observed. This suggests that the surface dust includes some components of different composition and/or structure--possibly fragments of codeposited layers. The oxidation of codeposit flakes scraped form DIII-D upper divertor tiles showed an initial 25% loss in mass due to heating in vacuum, and the gradual loss of 30-38% mass during the subsequent 24 hours exposure to O 2 . This behavior is significantly different from that observed for the oxidation of thinner DIII-D codeposit specimens which were still adhered to tile surfaces, and this is thought to be related to the low deuterium content (D/C ∼ 0.03-0.04) of the flakes

  13. Thermo-oxidation of tokamak carbon dust

    International Nuclear Information System (INIS)

    Davis, J.W.; Fitzpatrick, B.W.N.; Sharpe, J.P.; Haasz, A.A.

    2009-01-01

    The oxidation of dust and flakes collected from the DIII-D tokamak, and various commercial dust specimens, has been measured at 350 deg. C and 2.0 kPa O 2 pressure. Following an initial small mass loss, most of the commercial dust specimens showed very little effect due to O 2 exposure. Similarly, dust collected from underneath DIII-D tiles, which is thought to comprise largely Grafoil TM particulates, also showed little susceptibility to oxidation at this temperature. However, oxidation of the dust collected from tile surfaces has led to ∼18% mass loss after 8 h; thereafter, little change in mass was observed. This suggests that the surface dust includes some components of different composition and/or structure - possibly fragments of codeposited layers. The oxidation of codeposit flakes scraped from DIII-D upper divertor tiles showed an initial 25% loss in mass due to heating in vacuum, and the gradual loss of 30-38% mass during the subsequent 24 h exposure to O 2 . The oxidation of these flakes was much slower than that observed for the oxidation of thinner DIII-D codeposit specimens which were still adhered to tile surfaces. This is thought to be related to structural differences.

  14. Lunar Dust Separation for Toxicology Studies

    Science.gov (United States)

    Cooper, Bonnie L.; McKay, D. S.; Riofrio, L. M.; Taylor, L. A.; Gonzalex, C. P.

    2010-01-01

    During the Apollo missions, crewmembers were briefly exposed to dust in the lunar module, brought in after extravehicular activity. When the lunar ascent module returned to micro-gravity, the dust that had settled on the floor now floated into the air, causing eye discomfort and occasional respiratory symptoms. Because our goal is to set an exposure standard for 6 months of episodic exposure to lunar dust for crew on the lunar surface, these brief exposures of a few days are not conclusive. Based on experience with industrial minerals such as sandblasting quartz, an exposure of several months may cause serious damage, while a short exposure may cause none. The detailed characteristics of sub-micrometer lunar dust are only poorly known, and this is the size range of particles that are of greatest concern. We have developed a method for extracting respirable dust (<2.5 micron) from Apollo lunar soils. This method meets stringent requirements that the soil must be kept dry, exposed only to pure nitrogen, and must conserve and recover the maximum amount of both respirable dust and coarser soil. In addition, we have developed a method for grinding coarser lunar soil to produce sufficient respirable soil for animal toxicity testing while preserving the freshly exposed grain surfaces in a pristine state.

  15. The Dust Management Project: Final Report

    Science.gov (United States)

    Hyatt, Mark J.; Straka, Sharon

    2011-01-01

    A return to the Moon to extend human presence, pursue scientific activities, use the Moon to prepare for future human missions to Mars, and expand Earth s economic sphere, will require investment in developing new technologies and capabilities to achieve affordable and sustainable human exploration. From the operational experience gained and lessons learned during the Apollo missions, conducting longterm operations in the lunar environment will be a particular challenge, given the difficulties presented by the unique physical properties and other characteristics of lunar regolith, including dust. The Apollo missions and other lunar explorations have identified significant lunar dust-related problems that will challenge future mission success. Comprised of regolith particles ranging in size from tens of nanometers to microns, lunar dust is a manifestation of the complex interaction of the lunar soil with multiple mechanical, electrical, and gravitational effects. The environmental and anthropogenic factors effecting the perturbation, transport, and deposition of lunar dust must be studied in order to mitigate it s potentially harmful effects on exploration systems and human explorers. The Dust Management Project (DMP) is tasked with the evaluation of lunar dust effects, assessment of the resulting risks, and development of mitigation and management strategies and technologies related to Exploration Systems architectures. To this end, the DMP supports the overall goal of the Exploration Technology Development Program (ETDP) of addressing the relevant high priority technology needs of multiple elements within the Constellation Program (CxP) and sister ETDP projects. Project scope, approach, accomplishments, summary of deliverables, and lessons learned are presented.

  16. Inhalation of road dust by human subjects.

    Science.gov (United States)

    Takishima, T; Nakamura, M; Sasaki, M; Miyano, M; Yamaya, M; Sasaki, H

    1987-11-01

    We measured pneumomagnetic field strength (PMFS) in 42 healthy control subjects living in districts of Northern Japan with low levels of road dust pollution and in 39 healthy subjects living in areas with high levels of road dust pollution. Suspended road dust produced by studded tires increases from 30 micrograms/m3 during the summer season to levels as high as 400 micrograms/m3 during the snow season in the downtown areas of Sendai, Japan. Road dust retained in the lungs, containing 3% iron, was magnetized from the surface of the chest wall, and PMFS was measured. Three to 5 sequential PMFS measurements were made in each subject in March and October of 1984 and 1985, and in March 1986. The PMFS in control subjects in March 1984 was 37 +/- 14 pico-Tesla (mean +/- SD) and did not significantly differ from the PMFS in October 1984 or that in March 1985. In March 1984, the PMFS of the subjects in highly polluted areas was 95 +/- 100 pico-Tesla (mean +/- SD) and was significantly higher than that of control subjects (p less than 0.01) and subsequently decreased in March 1985 and in March 1986, corresponding to a decrease in suspended road dust brought about by a campaign to eliminate the use of studded tires. Our findings suggest that some road dust caused by studded tires is retained in the lungs.

  17. Modeling Respiratory Toxicity of Authentic Lunar Dust

    Science.gov (United States)

    Santana, Patricia A.; James, John T.; Lam, Chiu-Wing

    2010-01-01

    The lunar expeditions of the Apollo operations from the 60 s and early 70 s have generated awareness about lunar dust exposures and their implication towards future lunar explorations. Critical analyses on the reports from the Apollo crew members suggest that lunar dust is a mild respiratory and ocular irritant. Currently, NASA s space toxicology group is functioning with the Lunar Airborne Dust Toxicity Assessment Group (LADTAG) and the National Institute for Occupational Safety and Health (NIOSH) to investigate and examine toxic effects to the respiratory system of rats in order to establish permissible exposure levels (PELs) for human exposure to lunar dust. In collaboration with the space toxicology group, LADTAG and NIOSH the goal of the present research is to analyze dose-response curves from rat exposures seven and twenty-eight days after intrapharyngeal instillations, and model the response using BenchMark Dose Software (BMDS) from the Environmental Protection Agency (EPA). Via this analysis, the relative toxicities of three types of Apollo 14 lunar dust samples and two control dust samples, titanium dioxide (TiO2) and quartz will be determined. This will be executed for several toxicity endpoints such as cell counts and biochemical markers in bronchoaveolar lavage fluid (BALF) harvested from the rats.

  18. Electronic design of air dust concentration gauge

    International Nuclear Information System (INIS)

    Machaj, B.; Strzalkowski, J.; Krawczynska, B.

    1993-01-01

    A new version of isotope dust concentration gauge for monitoring airborne dust pollution of air employs a ready made personal computer as the control and processing unit in the gauge instead of specialized electronics. That solution of the gauge reduces the needed specialized electronics to a simple computer interface coupling the computer to the measuring head. This also reduced electronics of the measuring head itself, i.e. GM detector circuit, power supplies and electronic circuits to switch on/off driving motors. The functioning and operation of the gauge is controlled by the computer program that can be easily modified if needed. The computer program for the gauge enables automatic measurements of dust concentration. Up to fifty measuring cycles can be easily programmed for a day. The results of measurements are presented in the form of data collection, diagram of dust concentration distribution during one day, diagram of dust distribution during 30 successive days or diagram of average dust concentration distribution during a day which may be computed by combining data of the selected number of measurements. Recalibration of the gauge and checking up of the gauge are also carried out under the program control. (author). 6 refs, 9 figs

  19. Control of dust hazards in mines

    Energy Technology Data Exchange (ETDEWEB)

    Sukhanov, V V

    1981-09-01

    This paper analyzes health hazards associated with air pollution by respirable coal dust which causes pneumoconioses. The following directions in pneumoconioses prevention are discussed: improved protective systems (e.g. respirators), mining schemes optimized from a health hazards point of view, correct determination of the maximum permissible level of respirable dusts, reducing working time. Safety regulations in the USSR on the critical amount of coal dust in the miner respiratory system are insufficient as the 20 g limit is too high and does not guarantee safety. Using regression analysis influence of the factors which cause pneumoconioses is analyzed. This influence is described by an equation which considers the following factors: number of shifts associated with contact of a miner with coal dusts, dust concentration in mine air, amount of air with coal dust being respirated, miner's age, years as miner, coal rank. It is stated that use of the proposed equation (derived by computer calculations) permits the safe working time to be correctly determined considering all factors which cause pneumoconioses.

  20. Radiative transfer in dust clouds

    International Nuclear Information System (INIS)

    Rowan-Robinson, M.; Harris, S.

    1983-01-01

    The infrared emission has been modelled from 85 late-type M stars, essentially all such stars in the AFGL catalogue with substantial circumstellar dust shells and for which adequate observational data are currently available. The dependence of the emergent spectrum on the temperature of the stars, the condensation temperature of the grains, and the density distribution, optical depth and extent of the shell have been investigated. Consistent models for most stars have been found using dirty silicate grains, with an n(r) proportional to r - 2 density distribution and a grain melting temperature of 1000 K. Allowance has been made for the effect of molecular bands. Although these bands have a dramatic effect on the spectrum of late-type stars at visual wavelengths, there is little effect on the infrared emission from the circumstellar shell. All stars in the study except GL 915, VY CMa and NML Cyg are consistent with having spherically symmetric shells. Except for VY CMa and NML Cyg, for which other evidence suggests a disc geometry, the intensity distributions predicted by the models are consistent with interferometric measurements at infrared wavelengths. (author)

  1. Dynamics of interplanetary dust grains

    International Nuclear Information System (INIS)

    Lamy, P.L.

    1975-01-01

    The interaction of spherical grains of various materials-three silicates (quartz, obsidian and andesite), water-ice and iron - whose radii lie in the micronic and submicronic range with the interplanetary medium is solved. This includes: the interaction with the solar radiation field which is solved using Mie scattering theory and taking into account the precise dependence of the optical properties of the five materials upon wavelength; the interaction with the solar wind: corpuscular tangential drag is found to be always important and may even be larger than the Poynting-Robertson drag; the interaction with the interplanetary magnetic field is investigated in terms of a diffusion or random walk through a series of electromagnetic scatterings, leading to a Chapman-Komolgorov equation (i.e., a generalized Liouville equation). Numerical results are presented for these interactions spanning the entire solar system with circularity of elliptical orbits, direct or retrograde, with grains of various materials and sizes and giving -probably for the first time - a clear global picture of the interaction of dust grains with the interplanetary medium. The dynamics of the grains is then investigated using the theory of general perturbations and the numerical integration of trajectories of circum-solar grains

  2. Palaearctic-African Bird Migration

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye Babatola

    Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans-Saharan m......Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans...... of birds from Europe to Africa and opens up the possibility of studying intra-African migration. I have used long-term, standardized autumn ringing data from southeast Sweden to investigate patterns in biometrics, phenology and population trends as inferred from annual trapping totals. In addition, I...... in the population of the species. The papers show that adult and juvenile birds can use different migration strategies depending on time of season and prevailing conditions. Also, the fuel loads of some individuals were theoretically sufficient for a direct flight to important goal area, but whether they do so...

  3. Investigation on nuclide migration behaviors

    International Nuclear Information System (INIS)

    Baik, Minhoon; Park, Chungkyun; Kim, Seungsoo

    2012-04-01

    In this study, we investigated the properties of geochemical reactions and sorption of high-level radionuclides and highly-mobile radionuclides in deep geological disposal environments. We also analyzed the dissolution properties of pyro wastes and constructed databases for the geochemical reactions and sorption for the safety assessment of HLW disposal. Technologies for measuring diffusion depths of radionuclides through fracture surfaces and rock matrix were developed in KURT conditions and their diffusion properties were analyzed and evaluated. The combined reactions of radionuclide/mineral/microbe in deep disposal environments were investigated and the effects of microbe on the radionuclide migration and disposal system behaviors were evaluated. In-situ solute migration system and on-line monitoring system were installed in KURT and the migration and retardation behaviors of various solutes and their interaction with fracture-filling materials were investigated. Basic properties of KURT groundwater colloids were analyzed using various methods. In addition, in-situ colloid migration experiments through a rock fracture were carried out and the developed migration model was verified. We have participated in Colloid Formation and Migration (CFM) international joint project in GTS and obtained reliability for our research results by comparing research results each other

  4. Transport of Mineral Dust and Its Impact on Climate

    Directory of Open Access Journals (Sweden)

    Kerstin Schepanski

    2018-04-01

    Full Text Available Mineral dust plays a pivotal role in the Earth’s system. Dust modulates the global energy budget directly via its interactions with radiation and indirectly via its influence on cloud and precipitation formation processes. Dust is a micro-nutrient and fertilizer for ecosystems due to its mineralogical composition and thus impacts on the global carbon cycle. Hence, dust aerosol is an essential part of weather and climate. Dust suspended in the air is determined by the atmospheric dust cycle: Dust sources and emission processes define the amount of dust entrained into the atmosphere. Atmospheric mixing and circulation carry plumes of dust to remote places. Ultimately, dust particles are removed from the atmosphere by deposition processes such as gravitational settling and rain wash out. During its residence time, dust interacts with and thus modulates the atmosphere resulting into changes such as in surface temperature, wind, clouds, and precipitation rates. There are still uncertainties regarding individual dust interactions and their relevance. Dust modulates key processes that are inevitably influencing the Earth energy budget. Dust transport allows for these interactions and at the same time, the intermittency of dust transport introduces additional fluctuations into a complex and challenging system.

  5. 'Nuisance Dust' - a Case for Recalibration?

    Science.gov (United States)

    Datson, Hugh; Marker, Brian

    2013-04-01

    This paper considers the case for a review and recalibration of limit values and acceptability criteria for 'nuisance dust', a widely encountered but poorly defined and regulated aspect of particulate matter pollution. Specific dust fractions such as PM10 and asbestiforms are well characterised and have limit values enshrined in legislation. National, and international, limit values for acceptable concentrations of PM10 and other fractions of particulate matter have been defined and agreed. In the United Kingdom (UK), these apply to both public and workplace exposures. By contrast, there is no standard definition or universal criteria against which acceptable levels for 'nuisance dust' can be assessed. This has implications for land-use planning and resource utilisation. Without meaningful limit values, inappropriate development might take place too near to residential dwellings or land containing economically important mineral resources may be effectively sterilised. Furthermore, the expression 'nuisance dust' is unhelpful in that 'nuisance' has a specific meaning in environmental law whilst 'nuisance dust' is often taken to mean 'generally visible particulate matter'. As such, it is associated with the social and broader environmental impacts of particulate matter. PM10 concentrations are usually expressed as a mass concentration over time. These can be determined using a range of techniques. While results from different instruments are generally comparable, data obtained from alternative methods for measuring 'nuisance dust' are rarely interchangeable. In the UK, many of the methods typically used are derived from approaches developed under the HMIP (Her Majesty's Inspectorate of Pollution) regime in the 1960s onwards. Typical methods for 'nuisance dust' sampling focus on measurement of dust mass (from the weight of dust collected in an open container over time) or dust soiling (from loss of reflectance and or obscuration of a surface discoloured by dust over

  6. Settlement process of radioactive dust to the ground inferred from the atmospheric electric field measurement

    Science.gov (United States)

    Yamauchi, M.; Takeda, M.; Makino, M.; Owada, T.; Miyagi, I.

    2012-01-01

    Radioactive materials from the accident at Fukushima Dai-ichi nuclear power plant (FNPP) in March 2011 spread over a large area, increasing the atmospheric electric conductivity by their ionizing effect, and reducing the vertical (downward) component of the DC electric field near the ground, or potential gradient (PG). PG data at Kakioka, 150 km away from the FNPP, showed independent changes compared to the radiation dose rate, and a comparison of these data revealed the local dynamics of the radioactive dust. (1) The initial drop of the PG to almost zero during 14-15 March is most likely due to radioactive dust suspended in the air near the ground during cloudy weather. (2) An episode of PG increase to more than 50 V m-1 on 16 March is most likely due to the re-suspension of the radioactive dust from the surface and subsequent removal from Kakioka by the strong wind from the non-contaminated area. (3) Low but finite values of the PG during 16-20 March most likely reflect a reduced amount of radioactive material near the ground after the above wind transported away the majority of the suspended radioactive dust. (4) Very low values of the PG after substantial rain on 20-22 March most likely reflect settlement of the radioactive material by rain-induced fallout. (5) Temporal recovery of daily variations from the end of March to the middle of April with low nighttime fair-weather baseline PG most likely reflects re-suspension of the radioactive dust into the air from the ground and trees, and subsequent transport to the other region or fallout to the ground until late April. (6) Weakening of the daily variation and gradual recovery of the nighttime fair-weather baseline after mid-April suggests a complete settlement of the radioactive material to the ground with partial migration to the subsurface.

  7. Settlement process of radioactive dust to the ground inferred from the atmospheric electric field measurement

    Directory of Open Access Journals (Sweden)

    M. Yamauchi

    2012-01-01

    Full Text Available Radioactive materials from the accident at Fukushima Dai-ichi nuclear power plant (FNPP in March 2011 spread over a large area, increasing the atmospheric electric conductivity by their ionizing effect, and reducing the vertical (downward component of the DC electric field near the ground, or potential gradient (PG. PG data at Kakioka, 150 km away from the FNPP, showed independent changes compared to the radiation dose rate, and a comparison of these data revealed the local dynamics of the radioactive dust. (1 The initial drop of the PG to almost zero during 14–15 March is most likely due to radioactive dust suspended in the air near the ground during cloudy weather. (2 An episode of PG increase to more than 50 V m−1 on 16 March is most likely due to the re-suspension of the radioactive dust from the surface and subsequent removal from Kakioka by the strong wind from the non-contaminated area. (3 Low but finite values of the PG during 16–20 March most likely reflect a reduced amount of radioactive material near the ground after the above wind transported away the majority of the suspended radioactive dust. (4 Very low values of the PG after substantial rain on 20–22 March most likely reflect settlement of the radioactive material by rain-induced fallout. (5 Temporal recovery of daily variations from the end of March to the middle of April with low nighttime fair-weather baseline PG most likely reflects re-suspension of the radioactive dust into the air from the ground and trees, and subsequent transport to the other region or fallout to the ground until late April. (6 Weakening of the daily variation and gradual recovery of the nighttime fair-weather baseline after mid-April suggests a complete settlement of the radioactive material to the ground with partial migration to the subsurface.

  8. Environmentally dependent dust chemistry of a super Asian dust storm in March 2010: observation and simulation

    Science.gov (United States)

    Wang, Qiongzhen; Dong, Xinyi; Fu, Joshua S.; Xu, Jian; Deng, Congrui; Jiang, Yilun; Fu, Qingyan; Lin, Yanfen; Huang, Kan; Zhuang, Guoshun

    2018-03-01

    Near-surface and vertical in situ measurements of atmospheric particles were conducted in Shanghai during 19-23 March 2010 to explore the transport and chemical evolution of dust particles in a super dust storm. An air quality model with optimized physical dust emission scheme and newly implemented dust chemistry was utilized to study the impact of dust chemistry on regional air quality. Two discontinuous dust periods were observed with one traveling over northern China (DS1) and the other passing over the coastal regions of eastern China (DS2). Stronger mixing extents between dust and anthropogenic emissions were found in DS2, reflected by the higher SO2 / PM10 and NO2 / PM10 ratios as well as typical pollution elemental species such as As, Cd, Pb, and Zn. As a result, the concentrations of SO42- and NO3- and the ratio of Ca2+ / Ca were more elevated in DS2 than in DS1 but opposite for the [NH4+] / [SO42-+NO3-] ratio, suggesting the heterogeneous reactions between calcites and acid gases were significantly promoted in DS2 due to the higher level of relative humidity and gaseous pollution precursors. Lidar observation showed a columnar effect on the vertical structure of particle optical properties in DS1 that dust dominantly accounted for ˜ 80-90 % of the total particle extinction from near the ground to ˜ 700 m. In contrast, the dust plumes in DS2 were restrained within lower altitudes while the extinction from spherical particles exhibited a maximum at a high altitude of ˜ 800 m. The model simulation reproduced relatively consistent results with observations that strong impacts of dust heterogeneous reactions on secondary aerosol formation occurred in areas where the anthropogenic emissions were intensive. Compared to the sulfate simulation, the nitrate formation on dust is suggested to be improved in the future modeling efforts.

  9. Migration of Organophosphate Flame Retardants from Closed Cell Foam to Settled Dust

    Science.gov (United States)

    Many industrial and consumer products, such as electrical and electronic products, furniture, plastics, textile, and building materials are manufactured with organophosphorus flame retardants (OPFRs). OPFRs can leach or diffuse out of the products and are released to the surround...

  10. Migration of Organophorus Flame Retardants From Closed cell form to Settled Dust

    Science.gov (United States)

    Many industrial and consumer products, such as electrical and electronic products, furniture, plastics, textile, and building materials are manufactured with organophosphorus flame retardants (OPFRs). OPFRs can leach or diffuse out of the products and are released to the surround...

  11. International migration: a global challenge.

    Science.gov (United States)

    Martin, P; Widgren, J

    1996-04-01

    Trends in international migration are presented in this multiregional analysis. Seven of the world's wealthiest countries have about 33% of the world's migrant population, but under 16% of the total world population. Population growth in these countries is substantially affected by the migrant population. The migration challenge is external and internal. The external challenge is to balance the need for foreign labor and the commitment to human rights for those migrants seeking economic opportunity and political freedom. The internal challenge is to assure the social adjustment of immigrants and their children and to integrate them into society as citizens and future leaders. Why people cross national borders and how migration flows are likely to evolve over the next decades are explained. This report also presents some ways that countries can manage migration or reduce the pressures which force people to migrate. It is recommended that receiving nations control immigration by accelerating global economic growth and reducing wars and human rights violations. This report examines the impact of immigration on international trade, aid, and direct intervention policies. Although migration is one of the most important international economic issues, it is not coordinated by an international group. The European experience indicates that it is not easy to secure international cooperation on issues that affect national sovereignty. It is suggested that countries desiring control of their borders should remember that most people never cross national borders to live or work in another country, that 50% of the world's migrants move among developing countries, and that countries can shift from being emigration to immigration countries. The author suggests that sustained reductions in migration pressure are a better alternative than the "quick fixes" that may invite the very much feared mass and unpredictable movements.

  12. DUST PROPERTIES OF LOCAL DUST-OBSCURED GALAXIES WITH THE SUBMILLIMETER ARRAY

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ho Seong; Andrews, Sean M.; Geller, Margaret J., E-mail: hhwang@cfa.harvard.edu, E-mail: sandrews@cfa.harvard.edu, E-mail: mgeller@cfa.harvard.edu [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States)

    2013-11-01

    We report Submillimeter Array observations of the 880 μm dust continuum emission for four dust-obscured galaxies (DOGs) in the local universe. Two DOGs are clearly detected with S{sub ν}(880 μm) =10-13 mJy and S/N > 5, but the other two are not detected with 3σ upper limits of S{sub ν}(880 μm) =5-9 mJy. Including an additional two local DOGs with submillimeter data from the literature, we determine the dust masses and temperatures for six local DOGs. The infrared luminosities and dust masses for these DOGs are in the ranges of 1.2-4.9 × 10{sup 11}(L{sub ☉}) and 4-14 × 10{sup 7}(M{sub ☉}), respectively. The dust temperatures derived from a two-component modified blackbody function are 23-26 K and 60-124 K for the cold and warm dust components, respectively. Comparison of local DOGs with other infrared luminous galaxies with submillimeter detections shows that the dust temperatures and masses do not differ significantly among these objects. Thus, as argued previously, local DOGs are not a distinctive population among dusty galaxies, but simply represent the high-end tail of the dust obscuration distribution.

  13. Dust Destruction in the ISM: A Re-Evaluation of Dust Lifetimes

    Science.gov (United States)

    Jones, A. P.; Nuth, J. A., III

    2011-01-01

    There is a long-standing conundrum in interstellar dust studies relating to the discrepancy between the time-scales for dust formation from evolved stars and the apparently more rapid destruction in supernova-generated shock waves. Aims. We re-examine some of the key issues relating to dust evolution and processing in the interstellar medium. Methods. We use recent and new constraints from observations, experiments, modelling and theory to re-evaluate dust formation in the interstellar medium (ISM). Results. We find that the discrepancy between the dust formation and destruction time-scales may not be as significant as has previously been assumed because of the very large uncertainties involved. Conclusions. The derived silicate dust lifetime could be compatible with its injection time-scale, given the inherent uncertainties in the dust lifetime calculation. The apparent need to re-form significant quantities of silicate dust in the tenuous interstellar medium may therefore not be a strong requirement. Carbonaceous matter, on the other hand, appears to be rapidly recycled in the ISM and, in contrast to silicates, there are viable mechanisms for its re-formation in the ISM.

  14. CHARACTERIZATION OF THE DUST GENERATED IN THE RECYCLING PROCESS OF THE ELECTRIC ARC FURNACE DUST

    Directory of Open Access Journals (Sweden)

    Fábio Gonçalves Rizz

    2013-10-01

    Full Text Available Electric Arc Furnace Dust (EAFD is a solid waste generated by the production of steel through the Electric Arc Furnace. This waste is labeled dangerous, which motivates studies aiming its recycling. Experiments were made to study a pyrometallurgical process for the recycling of the dust, using the insertion of dust briquettes in molten pig iron in three temperatures. In the briquettes, there were made additions of calcium fluoride in four different concentrations. This paper has the objective to characterize the dust that results from this process, verifying the influence of the temperature and the concentration of calcium fluoride in the briquette in the morphology and chemical composition of the new dust, determining the optimal conditions for the recovery of the zinc content of the dust. This newly generated dust was analyzed in an Scanning Electronic Microscope, used to capture micrographs and chemical composition by EDS. The micrographs show that the temperature and the calcium fluoride concentration interfere in the way the dust particles agglomerate. Chemical analysis points that the higher zinc recuperation occurrs in the experiments at 1500°C with 7% addition of calcium fluoride.

  15. Dust-cyclotron and dust-lower-hybrid modes in self-gravitating ...

    Indian Academy of Sciences (India)

    cantly modifies the dispersion properties of these two electrostatic modes. The implications of these results to some space and astrophysical dusty plasma systems, especially to planetary ring-systems and cometary tails, are briefly mentioned. Keywords. Dusty plasmas; dust-cyclotron waves; dust-lower-hybrid waves.

  16. The flow of interstellar dust through the solar system: the role of dust charging

    International Nuclear Information System (INIS)

    Sterken, V. J.; Altobelli, N.; Schwehm, G.; Kempf, S.; Srama, R.; Strub, P.; Gruen, E.

    2011-01-01

    Interstellar dust can enter the solar system through the relative motion of the Sun with respect to the Local Interstellar Cloud. The trajectories of the dust through the solar system are not only influenced by gravitation and solar radiation pressure forces, but also by the Lorentz forces due to the interaction of the interplanetary magnetic field with the charged dust particles. The interplanetary magnetic field changes on two major time scales: 25 days (solar rotation frequency) and 22 years (solar cycle). The short-term variability averages out for regions that are not too close (>∼2 AU) to the Sun. This interplanetary magnetic field variability causes a time-variability in the interstellar dust densities, that is correlated to the solar cycle.In this work we characterize the flow of interstellar dust through the solar system using simulations of the dust trajectories. We start from the simple case without Lorentz forces, and expand to the full simulation. We pay attention to the different ways of modeling the interplanetary magnetic field, and discuss the influence of the dust parameters on the resulting flow patterns. We also discuss the possibilities of using this modeling for prediction of dust fluxes for different space missions or planets, and we pay attention to where simplified models are justified, and where or when a full simulation, including all forces is necessary. One of the aims of this work is to understand measurements of spacecraft like Ulysses, Cassini and Stardust.

  17. Variations between Dust and Gas in the Diffuse Interstellar Medium. III. Changes in Dust Properties

    Science.gov (United States)

    Reach, William T.; Bernard, Jean-Philippe; Jarrett, Thomas H.; Heiles, Carl

    2017-12-01

    We study infrared emission of 17 isolated, diffuse clouds with masses of order {10}2 {M}ȯ to test the hypothesis that grain property variations cause the apparently low gas-to-dust ratios that have been measured in those clouds. Maps of the clouds were constructed from Wide-field Infrared Survey Explorer (WISE) data and directly compared with the maps of dust optical depth from Planck. The mid-infrared emission per unit dust optical depth has a significant trend toward lower values at higher optical depths. The trend can be quantitatively explained by the extinction of starlight within the clouds. The relative amounts of polycyclic aromatic hydrocarbon and very small grains traced by WISE, compared with large grains tracked by Planck, are consistent with being constant. The temperature of the large grains significantly decreases for clouds with larger dust optical depth; this trend is partially due to dust property variations, but is primarily due to extinction of starlight. We updated the prediction for molecular hydrogen column density, taking into account variations in dust properties, and find it can explain the observed dust optical depth per unit gas column density. Thus, the low gas-to-dust ratios in the clouds are most likely due to “dark gas” that is molecular hydrogen.

  18. DUST PROPERTIES OF LOCAL DUST-OBSCURED GALAXIES WITH THE SUBMILLIMETER ARRAY

    International Nuclear Information System (INIS)

    Hwang, Ho Seong; Andrews, Sean M.; Geller, Margaret J.

    2013-01-01

    We report Submillimeter Array observations of the 880 μm dust continuum emission for four dust-obscured galaxies (DOGs) in the local universe. Two DOGs are clearly detected with S ν (880 μm) =10-13 mJy and S/N > 5, but the other two are not detected with 3σ upper limits of S ν (880 μm) =5-9 mJy. Including an additional two local DOGs with submillimeter data from the literature, we determine the dust masses and temperatures for six local DOGs. The infrared luminosities and dust masses for these DOGs are in the ranges of 1.2-4.9 × 10 11 (L ☉ ) and 4-14 × 10 7 (M ☉ ), respectively. The dust temperatures derived from a two-component modified blackbody function are 23-26 K and 60-124 K for the cold and warm dust components, respectively. Comparison of local DOGs with other infrared luminous galaxies with submillimeter detections shows that the dust temperatures and masses do not differ significantly among these objects. Thus, as argued previously, local DOGs are not a distinctive population among dusty galaxies, but simply represent the high-end tail of the dust obscuration distribution

  19. Numerical investigation on the combined effects of varying piston bowl geometries and ramp injection rate-shapes on the combustion characteristics of a kerosene-diesel fueled direct injection compression ignition engine

    International Nuclear Information System (INIS)

    Tay, Kun Lin; Yang, Wenming; Zhao, Feiyang; Yu, Wenbin; Mohan, Balaji

    2017-01-01

    Highlights: • Effect of injection rate-shaping on heat-release is significant with less turbulence. • Two peak heat-releases are seen for the shallow-depth re-entrant piston. • Significant combustion phasing occurs with kerosene usage and high turbulence. - Abstract: In this work, the combustion characteristics of a direct injection compression ignition (DICI) engine fueled with kerosene-diesel blends, using different piston bowl geometries together with varying injection rate-shapes were investigated. A total of three combustion bowl geometries, namely the omega combustion chamber (OCC), the shallow-depth combustion chamber (SCC) and the shallow-depth re-entrant combustion chamber (SRCC), were used together with six different ramp injection rate-shapes and pure diesel, kerosene-diesel and pure kerosene fuels. It is seen that the SRCC geometry, which has the shortest throat length, gives the highest turbulence kinetic energy (TKE) and this resulted in two peak heat-releases, with a primary peak heat-release during the premixed combustion phase and a secondary peak heat-release during the mixing-controlled combustion phase. In addition, the SCC geometry gives rather distinct premixed combustion and mixing-controlled combustion phases due to the fact that combustion is predominantly controlled by the injected fuel spray itself because of less turbulence. Also, when kerosene is used in place of diesel, the heat-release during the premixed combustion phase increases and diminishes during the mixing-controlled and late combustion phases. It is interesting to note that the effect of injection rate-shaping on the heat-release rate is more obvious for bowl geometries that generate less TKE. Moreover, bowl geometries that generate higher TKEs as well as fuels with lower viscosities generally give lower carbon monoxide (CO) emissions and higher nitrogen oxide (NO) emissions. More importantly, it is possible to achieve low NO and CO emissions simultaneously by using the

  20. Electrostatic Dust Detection and Removal for ITER

    International Nuclear Information System (INIS)

    C.H. Skinner; A. Campos; H. Kugel; J. Leisure; A.L. Roquemore; S. Wagner

    2008-01-01

    We present some recent results on two innovative applications of microelectronics technology to dust inventory measurement and dust removal in ITER. A novel device to detect the settling of dust particles on a remote surface has been developed in the laboratory. A circuit board with a grid of two interlocking conductive traces with 25 (micro)m spacing is biased to 30-50 V. Carbon particles landing on the energized grid create a transient short circuit. The current flowing through the short circuit creates a voltage pulse that is recorded by standard nuclear counting electronics and the total number of counts is related to the mass of dust impinging on the grid. The particles typically vaporize in a few seconds restoring the previous voltage standoff. Experience on NSTX however, showed that in a tokamak environment it was still possible for large particles or fibers to remain on the grid causing a long term short circuit. We report on the development of a gas puff system that uses helium to clear such particles. Experiments with varying nozzle designs, backing pressures, puff durations, and exit flow orientations have given an optimal configuration that effectively removes particles from an area up to 25 cm 2 with a single nozzle. In a separate experiment we are developing an advanced circuit grid of three interlocking traces that can generate a miniature electrostatic traveling wave for transporting dust to a suitable exit port. We have fabricated such a 3-pole circuit board with 25 micron insulated traces that operates with voltages up to 200 V. Recent results showed motion of dust particles with the application of only 50 V bias voltage. Such a device could potentially remove dust continuously without dedicated interventions and without loss of machine availability for plasma operations